WO2020175375A1 - Hollow fiber membrane, hollow fiber membrane production method, hollow fiber membrane module, membrane separator, and membrane separation method - Google Patents

Hollow fiber membrane, hollow fiber membrane production method, hollow fiber membrane module, membrane separator, and membrane separation method Download PDF

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Publication number
WO2020175375A1
WO2020175375A1 PCT/JP2020/007080 JP2020007080W WO2020175375A1 WO 2020175375 A1 WO2020175375 A1 WO 2020175375A1 JP 2020007080 W JP2020007080 W JP 2020007080W WO 2020175375 A1 WO2020175375 A1 WO 2020175375A1
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Prior art keywords
hollow fiber
liquid
fiber membrane
chamber
membrane
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PCT/JP2020/007080
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French (fr)
Japanese (ja)
Inventor
昌平 合田
櫻井 秀彦
崇人 中尾
泰樹 寺島
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東洋紡株式会社
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Application filed by 東洋紡株式会社 filed Critical 東洋紡株式会社
Priority to JP2021502195A priority Critical patent/JP6912019B2/en
Priority to CN202080005020.1A priority patent/CN112672812A/en
Publication of WO2020175375A1 publication Critical patent/WO2020175375A1/en

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D61/00Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor
    • B01D61/02Reverse osmosis; Hyperfiltration ; Nanofiltration
    • B01D61/08Apparatus therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D63/00Apparatus in general for separation processes using semi-permeable membranes
    • B01D63/02Hollow fibre modules
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D69/00Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D69/00Semi-permeable membranes for separation processes or apparatus characterised by their form, structure or properties; Manufacturing processes specially adapted therefor
    • B01D69/08Hollow fibre membranes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/08Polysaccharides
    • B01D71/10Cellulose; Modified cellulose
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/56Polyamides, e.g. polyester-amides
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D71/00Semi-permeable membranes for separation processes or apparatus characterised by the material; Manufacturing processes specially adapted therefor
    • B01D71/06Organic material
    • B01D71/66Polymers having sulfur in the main chain, with or without nitrogen, oxygen or carbon only
    • B01D71/68Polysulfones; Polyethersulfones
    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01DMECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS
    • D01D5/00Formation of filaments, threads, or the like
    • D01D5/06Wet spinning methods

Definitions

  • the present invention relates to a hollow fiber membrane, a method for producing a hollow fiber membrane, a hollow fiber membrane module, a membrane separation device, and a membrane separation method.
  • the RO method when producing fresh water from seawater, the RO method is used.
  • seawater which has been pressurized to a predetermined pressure higher than the osmotic pressure by a high-pressure pump, is supplied to the reverse osmosis (R 0: Reverse Osmosis) module and passed through the RO membrane to remove salts, etc. in seawater. Take out fresh water. The rest of the seawater is discharged from the RO module as concentrated brine (brine).
  • R 0 Reverse Osmosis
  • the BC method requires less energy than the RO method.
  • Patent Document 1 Japanese Unexamined Patent Publication No. 20108-1111
  • a part of the target solution is caused to flow into one of the first chambers of the hollow fiber membrane module, and the other of the second chamber is used.
  • the water contained in the target solution in the first chamber is transferred to the second chamber through the hollow fiber membrane,
  • a membrane separation method is disclosed in which the target solution in one chamber is concentrated and the target solution in the second chamber is diluted.
  • the other side of the hollow fiber membrane is basically water without osmotic pressure. It is necessary to pressurize the target solution with a high pressure that overcomes the pressure. Since the pressurization pressure is limited by the operating pressure (limit pressure) of the hollow fiber membrane and the maximum pressure of the pump to be used, [In method III, the osmotic pressure of the target solution is the operating pressure of the hollow fiber membrane. The target solution cannot be concentrated to a high concentration that exceeds the pressure or the maximum pressure of the pump.
  • Patent Documents 2 to 6 a raw material solution is discharged from a nozzle through an in-air traveling portion into a coagulating liquid to be coagulated, and the coagulated product is sequentially pulled out from the coagulating liquid to form a hollow fiber membrane.
  • a hollow fiber membrane comprising a step of obtaining (spinning step), and a step of washing the hollow fiber membrane obtained in the spinning step with water and then subjecting it to at least one of hot water treatment and salting treatment (post-treatment step). Is disclosed.
  • Patent Document 1 Japanese Patent Laid-Open No. 2018_1111
  • Patent Document 2 International Publication No. 2 0 1 2/0 2 6 3 7 3
  • Patent Document 3 International Publication No. 2 0 1 3/1 1 8 8 5 9
  • Patent Document 4 International Publication No. 2 0 1 3/1 2 5 6 8 1
  • Patent Document 5 JP 2 0 1 3 _ 1 9 8 8 9 3 Publication
  • Patent Document 6 International Publication No. 2 0 1 7/1 2 2 6 7 3 Summary of Invention ⁇ 2020/175375 3 ⁇ (:171? 2020/007080 Issues to be solved by the invention
  • the method (3) [It is desirable that the inner diameter (head) be made larger than that of a normal hollow fiber membrane ([3 ⁇ 4 membrane] used in the method III to reduce the pressure loss inside the hollow fiber membrane.
  • a normal hollow fiber membrane [3 ⁇ 4 membrane] used in the method III to reduce the pressure loss inside the hollow fiber membrane.
  • hollow fiber membranes with an inner diameter (head) larger than that of a normal 80 membrane decreased the inner diameter of the hollow fiber membrane with time when used for membrane separation by the method (3). ..
  • an object of the present invention is to suppress the decrease in the inner diameter of the hollow fiber membrane over time when the hollow fiber membrane is used for membrane separation by the method (3).
  • a hollow fiber membrane which is a hollow fiber type semipermeable membrane
  • the shrinkage ratio of the inner diameter of the hollow fiber membrane after being used for a predetermined membrane separation method for 96 hours is ⁇ 0.1% and less than 9% with respect to the inner diameter at the start of use
  • the predetermined membrane separation method uses a hollow fiber membrane module having the hollow fiber membrane and a first chamber and a second chamber partitioned by the hollow fiber membrane, and the first liquid is subjected to the first pressure at the first pressure.
  • the solvent contained in the first liquid in the first chamber is passed through the hollow fiber membrane.
  • the outer space of the hollow fiber membrane is the first chamber
  • the inner space of the hollow fiber membrane is the second chamber
  • the first pressure is 5.
  • the second pressure is constant, ⁇ 2020/175 375 4 ⁇ (: 171-1? 2020 /007080
  • a hollow fiber membrane wherein the osmotic pressure difference between the first liquid and the second liquid is 0 ! ⁇ /1 3 .
  • the inner diameter of the hollow fiber membrane is 40 or more and 200 or less
  • the hollow fiber membrane according to any one of (1) to (4) which is composed of a material containing at least one of a cellulose resin, a polysulfone resin, and a polyamide resin.
  • a hollow fiber membrane module having the hollow fiber membrane and a first chamber and a second chamber partitioned by the hollow fiber membrane is used to apply the first liquid to the first pressure at the first pressure.
  • the hollow fiber membrane according to any one of (1) to (5), which is used in a membrane separation method in which the osmotic pressure difference between the first liquid and the second liquid is 4 IV! 3 or less.
  • a method for producing a hollow fiber membrane comprising:
  • the raw material solution contains a solvent and a non-solvent, the mass ratio of the solvent / non-solvent in the raw material solution is 50/50 ⁇ 70 / 30,
  • the draw ratio which is the ratio of the drawing speed to the discharge speed of the raw material solution at the outlet of the nozzle, is 2.1 to 5.0, ⁇ 2020/175 375 5 (:171? 2020/007080
  • the manufacturing method wherein the temperature of the salting treatment is not less than 70° and not more than 95°.
  • a membrane separation device including the hollow fiber membrane module according to (9),
  • the first liquid in the first chamber By flowing the first liquid to the first chamber at a first pressure and the second liquid to the second chamber at a second pressure lower than the first pressure, the first liquid in the first chamber
  • the solvent contained in the liquid is transferred to the second liquid in the second chamber through the hollow fiber membrane, and the concentrated liquid which is the concentrated first liquid is discharged from the first chamber, Discharge the diluted liquid which is the second liquid diluted from
  • the osmotic pressure difference of the first liquid and the second liquid is 4 IV!? 3 or less, the membrane separation apparatus.
  • the first liquid in the first chamber By flowing the first liquid to the first chamber at a first pressure and the second liquid to the second chamber at a second pressure lower than the first pressure, the first liquid in the first chamber
  • the solvent contained in the liquid is transferred to the second liquid in the second chamber through the hollow fiber membrane, and the concentrated liquid which is the concentrated first liquid is discharged from the first chamber, Discharge the diluted liquid which is the second liquid diluted from
  • the hollow fiber membrane when used for membrane separation by the method ( 3), it is possible to suppress a decrease in the inner diameter of the hollow fiber membrane over time.
  • Fig. 1 is a schematic view showing a membrane separation device of Embodiment 1.
  • FIG. 2 A schematic view showing a hollow fiber membrane module.
  • FIG. 3 is a schematic cross-sectional view showing a hollow fiber membrane module.
  • FIG. 4 is a graph showing the relationship between the elapsed time from the start of the test and the change rate of the average flow rate in the hollow fiber membranes of the hollow fiber membranes of Examples 1 and 2 and Comparative Example 2. 5]
  • a pattern used to measure the shrinkage ratio of the inner diameter of the hollow fiber membrane (a schematic diagram for explaining the outline of 3 tests.
  • FIG. 6 is a schematic diagram for explaining an example of a method for manufacturing a hollow fiber membrane.
  • Fig. 7 is a schematic diagram for explaining a method for measuring a Raman value.
  • FIG. 8 A schematic diagram for explaining a method for measuring a Raman value.
  • Fig. 9 is a schematic diagram for explaining a method for measuring a Raman value.
  • FIG. 10 is a graph showing an example of the analysis result by Raman spectroscopy.
  • Fig. 11 is a schematic diagram for explaining a method of calculating the thinnest thickness/thickness of the hollow fiber membrane.
  • the membrane separation device of the present embodiment includes a hollow fiber membrane module 1.
  • the hollow fiber membrane module 1 has a hollow fiber membrane 10 and a first chamber 11 and a second chamber 12 partitioned by the hollow fiber membrane 10. ⁇ 2020/175 375 7 (: 171-1? 2020 /007080
  • the first liquid is caused to flow into the first chamber 11 at the first pressure
  • the second liquid is caused to flow into the second chamber 12 at the second pressure lower than the first pressure.
  • the solvent contained in the first liquid in the first chamber 11 was transferred to the second liquid in the second chamber 12 through the hollow fiber membrane, and the concentrated liquid (concentrated liquid was collected from the first chamber 11).
  • the first liquid) is discharged, and the diluted liquid (diluted second liquid) is discharged from the second chamber 12. In this way, the first liquid can be concentrated and the second liquid can be diluted.
  • hollow fiber membrane 10 is drawn like a flat membrane in FIG. 1 for simplification, the hollow fiber membrane used in this embodiment is shown in FIGS. 2 and 3 described later. It is a hollow fiber type semipermeable membrane (hollow fiber membrane 10). Hollow fiber membranes can increase the membrane area per volume of the membrane module and can increase the membrane permeation flow rate per volume of the membrane module compared to a spiral type semipermeable membrane. It is advantageous.
  • the hollow fiber membrane module includes a plurality of hollow fiber membranes, and each of the plurality of hollow fiber membranes preferably has openings at both ends.
  • the first chamber 11 is outside the hollow fiber membrane
  • the two chambers 12 are preferably inside the hollow fiber membrane. That is, the solution on the outer side of the hollow fiber membrane is preferably pressurized more than the solution on the inner side. Even if the solution flowing inside the hollow fiber membrane (hollow part) is pressurized, the pressure loss may increase and it may be difficult to pressurize sufficiently. In addition, the structure of the hollow fiber membrane itself is This is because it is easy to hold and the membrane may burst if a high internal pressure is applied. However, when using a hollow fiber membrane with a small pressure loss, that is, a large inner diameter and a large pressure resistance against the internal pressure, there is no particular problem even if the first chamber 11 is inside the hollow fiber membrane. However, in the hollow fiber membrane module used to measure the inner diameter shrinkage of the hollow fiber membrane described above, the first chamber 11 is outside the hollow fiber membrane and the second chamber 12 is inside the hollow fiber membrane. is there.
  • the osmotic pressure difference between the first liquid and the second liquid is It is the following.
  • the permeation pressure difference between the first and second liquids is shown by the following formula.
  • [Osmotic pressure difference] [Osmotic pressure of the first liquid]-[Osmotic pressure of the second liquid]
  • "osmotic pressure of the first liquid” means the first pressure of the hollow fiber membrane module 1. ⁇ 2020/175 375 8 (: 171-1? 2020 /007080
  • the osmotic pressure of the first liquid immediately before being supplied to the chamber 11 is the osmotic pressure of the first liquid immediately before being supplied to the chamber 11, and the "osmotic pressure of the second liquid” is the osmotic pressure of the second liquid immediately before being supplied to the second chamber 12 of the hollow fiber membrane module 1. It is the osmotic pressure.
  • the stipulation that the osmotic pressure difference is 4 IV! 3 or less means that the osmotic pressure difference has a negative (minus) value.
  • the osmotic pressure difference is preferably 3.5 IV! 3 or less.
  • the predetermined pressure (first pressure) of the first liquid flowing into the first chamber 11 is not particularly limited, but is preferably 3 to 101 ⁇ /1 3, and more preferably 5 to 10. It is 8.5 1 ⁇ /1 ⁇ .
  • the membrane separation by the method ⁇ can be carried out.
  • the ratio of the “osmotic pressure difference” to the “pressure difference between the first liquid and the second liquid” is preferably 50% or less, more preferably 30% or less.
  • the provisions of "50% or less” and “30% or less” include cases where the ratio of the osmotic pressure difference is a negative value.
  • the reverse osmosis occurs against the high osmotic pressure difference between the target liquid (high osmotic liquid) and fresh water as in Method III. It is possible to carry out membrane separation of the target liquid by pressurizing at a relatively low pressure (the first liquid can be concentrated and the second liquid can be diluted) without the need for high pressure to cause it. In addition, by using Mitsumi, it becomes possible to further concentrate the target liquid having a higher concentration than that of the method.
  • the osmotic pressure difference may be 0 1 ⁇ /1 3.
  • the first liquid and the second liquid may be the same liquid or different liquids.
  • the concentrations of the 1st and 2nd liquids are above the minimum concentration and below the saturation concentration that show effective osmotic pressure. Preferably 3.
  • the membrane separator is a pressure drop device, for example, a high pressure pump 31. ⁇ 2020/175375 9 boxes (: 171-1?2020/007080
  • It may be equipped with a diversion valve 4 or the like that allows the target liquid pressurized to a constant pressure to flow separately into the first chamber 11 and the second chamber 12 of the hollow fiber membrane module 1 (Fig. 1).
  • the flow dividing valve 4 (pressure reducing device) has a function of reducing the pressure of the target liquid flowing in the second chamber 12 to a pressure lower than a predetermined pressure.
  • the first liquid and the second liquid are liquids having an osmotic pressure.
  • the liquid may be a solution in which a solute is dissolved in a solvent, or may be a dispersion liquid in which an insoluble substance is dispersed.
  • Solutes include soluble substances such as inorganic or organic salts, acids, alkalis, alcohols, sugars and proteins.
  • the solvent include substances capable of dissolving or dispersing these solutes or insoluble substances to form a solution having an osmotic pressure.
  • Such a solvent is typically water, but may be a liquid other than water such as alcohol.
  • Examples of the first liquid and the second liquid include seawater, river water, brackish water, wastewater, organic solvents, foods and beverages.
  • wastewater include industrial wastewater, domestic wastewater, and oilfield or gasfield wastewater (associated water).
  • the first liquid and the second liquid supplied to the membrane separation device are concentrated brine (brine) discharged in the reverse osmosis process. It may be.
  • the membrane separation device may be a one-stage device using one hollow fiber membrane module 1 as shown in Fig. 1, or a multi-stage device using a plurality of hollow fiber membrane modules. May be
  • the first liquid and the second liquid may be pretreated to remove fine particles, microorganisms and the like contained in the liquid.
  • pretreatment seawater freshwater
  • Membrane Filtration using Microfiitration Membrane), addition of sodium hypochlorite, addition of coagulant, etc.
  • a pretreatment device (not shown) may be provided on the upstream side of the high pressure pump 31.
  • the pretreatment device is a device that treats the undiluted solution (target solution) taken by the pump 30 with sand filtration, UF membrane, MF membrane, and force-to-fill film.
  • the pretreatment device can remove turbidity from the stock solution to obtain a water-quality stock solution suitable for a membrane separation device including the hollow fiber membrane module 1 and the like. If necessary, it is possible to add pH adjusting means and chlorine addition equipment.
  • the hollow fiber membrane module 1 includes a core tube (a porous pipe) 2 having a plurality of holes 21 arranged at the center, and a plurality of core tubes arranged around it.
  • a hollow fiber membrane 10 and two resin walls 61 for fixing the core tube 2 and a plurality of hollow fiber membranes 10 at both ends thereof are provided.
  • the plurality of hollow fiber membranes 10 have openings at both ends.
  • the hollow fiber membrane element including these members is held in a pressure vessel 7 in a liquid-tight state in which two holding members 62 are provided with a _ ring 62 a.
  • the hollow fiber membrane module 1 has four ports (first liquid supply port 100a, first liquid discharge port 100b, second liquid supply port 101a, and second liquid discharge port 101).
  • the first liquid supply port 100 a communicates with the inside of the core tube 2 and further communicates with the outside 100 of the hollow fiber membrane 10 via the hole 21 of the core tube 2.
  • the first liquid outlet 100b communicates with the outside 100 of the hollow fiber membrane 10.
  • the second liquid supply port 101a and the second liquid discharge port 101b are connected to the opening (first opening) of the hollow fiber membrane 10. ⁇ 2020/175 375 1 1 ⁇ (:171? 2020 /007080
  • the first liquid is supplied into the core tube 2 through the first liquid supply port 1003, and is flown to the outer side 100 of the hollow fiber membrane 10 through the hole 21.
  • the first liquid that has passed the outer side 100 of the hollow fiber membrane 10 is taken out from the first liquid discharge port 100.
  • the second liquid is supplied to the first opening 1 of the hollow fiber membrane 10 through the second liquid supply port 1013.
  • the second liquid flowing through the hollow fiber membrane 10 and passing through the hollow fiber membrane 10 is taken out from the second liquid discharge port 1 0 1 13 via the second opening portion 10 of the hollow fiber membrane 10.
  • the fluid (first liquid) flowing inside (hollow part) of the hollow fiber membrane pressure loss is large and it is difficult to pressurize the first liquid sufficiently. Is preferably flowed to 100 outside the hollow fiber membrane 10.
  • the first liquid is placed on the outer side 100 of the hollow fiber membrane 10.
  • the second liquid may be allowed to flow into the hollow portion of the hollow fiber membrane 10 while flowing, and conversely, the second liquid may be caused to flow to the outside 100 of the hollow fiber membrane 10 and the first liquid of the hollow fiber membrane 10. It may be poured into the hollow part.
  • the inside of the hollow fiber membrane 10 may be the first chamber and the outside of the hollow fiber membrane 10 may be the second chamber, and conversely, the outside of the hollow fiber membrane 10 may be outside. May be the first chamber and the inside of the hollow fiber membrane 10 may be the second chamber.
  • the core tube 2 is not particularly limited as long as it is a tubular body having a plurality of holes 21. Hole 2
  • the core tube 2 is preferably arranged substantially in the center of the hollow fiber membrane module 1.
  • first liquid outlet 1 0 0, the second liquid supply port 1 0 1 3 and the second liquid outlet 1 0 1 are provided on the wall members 1 3 and 1 4, but are not limited to such a form. Instead, it can be changed appropriately.
  • At least one of the second liquid discharge port 101 and the second liquid discharge port 101 may be provided on the outer peripheral portion of the pressure vessel 7.
  • the form of the hollow fiber membrane module is not particularly limited.
  • Examples include a module in which hollow fiber membranes are straightly arranged as shown in 3, and a crosswind type module in which hollow fiber membranes are wound around a core tube.
  • the hollow fiber membrane of the present embodiment is a hollow fiber type semipermeable membrane.
  • the shrinkage rate (reduction rate) of the inner diameter of the hollow fiber membrane after being used for a predetermined membrane separation method described below for 96 hours is 0.1% with respect to the inner diameter at the start of use. % Or more and less than 9%.
  • the predetermined membrane separation method is performed by using a hollow fiber membrane, a first chamber and a first chamber that are partitioned by the hollow fiber membrane.
  • the first liquid is caused to flow into the first chamber at the first pressure
  • the second liquid is caused to flow into the second chamber at the second pressure lower than the first pressure
  • the solvent contained in the first liquid in the first chamber is transferred to the second liquid in the second chamber through the hollow fiber membrane, and the concentrated liquid, which is the concentrated first liquid, is discharged from the first chamber, and the second liquid is discharged. Drain the diluted solution, which is the second diluted solution, from the chamber.
  • the space outside the hollow fiber membrane is the first chamber, and the space inside the hollow fiber membrane is the second chamber.
  • the first pressure is 5.
  • the second pressure is constant (the pressure loss inside the hollow fiber membrane is constant).
  • the osmotic pressure difference between the first and second solutions is 0 1 ⁇ /1 3 .
  • the hollow fiber membrane was continuously used in the above-mentioned membrane separation method, and after the lapse of 96 hours from the start of use, the flow rate at the inflow port and the flow rate at the outflow port inside the hollow fiber membrane were measured to obtain the hollow fiber membrane. Calculate the average value (average flow rate in the hollow fiber membrane) of the flow rate at the inlet and the flow rate at the outlet inside the membrane. Regarding the average flow rate in the hollow fiber membrane after the lapse of 96 hours, the ratio of the decrease amount from the average flow rate in the hollow fiber membrane at the start of use to the average flow rate in the hollow fiber membrane at the start of use (in the hollow fiber membrane Average flow reduction rate) ⁇ 2020/175 375 13 ⁇ (: 171? 2020/007080
  • the flow rate is proportional to the fourth power of the inner diameter of the hollow fiber membrane
  • the relationship can be used to calculate the shrinkage rate of the inner diameter of the hollow fiber membrane from the reduction rate of the average flow rate inside the hollow fiber membrane. Since the pressure loss inside the hollow fiber membrane is constant, it is not necessary to consider the pressure loss.
  • the inner diameter of the hollow fiber membrane is preferably 40 or more and 200 or less, more preferably 750 or more and 180 or less.
  • the thickness of the hollow fiber membrane (whole membrane) is preferably 40 to 200, and more preferably 50 to 170.
  • the film thickness can be calculated by (outer diameter-inner diameter)/2.
  • the hollowness of the hollow fiber membrane is preferably 10 to 50%, more preferably 12 to 40%.
  • the hollow ratio is the ratio of the area of the hollow part in the cross section of the hollow fiber membrane, and is expressed as "hollow part cross-sectional area / (membrane cross-sectional area + hollow part cross-sectional area) X 100 (%)". expressed.
  • the average pore diameter of the hollow fiber membrane (average pore diameter of the membrane entire micropores) is preferably not more than 2 n m.
  • the differential scanning calorimetry (030 method) can be mentioned.
  • the Raman value of a hollow fiber membrane means a plurality of Raman spectra obtained by Raman spectroscopy at a plurality of points in the thickness direction of the cross section of the hollow fiber membrane swollen with water.
  • the Raman value is a value that serves as an index of the density distribution in the thickness direction of the hollow fiber membrane, and the higher the Raman value, the higher the Raman value. ⁇ 2020/175 375 14 (:171? 2020/007080
  • the Raman value of the hollow fiber membrane is preferably 72% or more and 90% or less. When the Raman value is within this range, when the hollow fiber membrane is used for membrane separation by the method (3), the effect of suppressing the decrease in the inner diameter of the hollow fiber membrane over time can be more reliably obtained.
  • Raman spectroscopy detects Raman scattered light generated by irradiating a measurement sample with laser light focused in a spot shape, and obtains a Raman spectrum by spectral analysis.
  • Method apparatus
  • the Raman spectrum is unique to a sample, and the intensity of the maximum peak in the Raman spectrum (peak unique to the main constituent material of the sample) for a certain sample is correlated with the density of the constituent material of the sample. Therefore, by measuring such peak intensity, it is possible to analyze the distribution state of the density of the constituent materials in the sample.
  • an objective lens having a spatial resolution of 2 or less is used as the objective lens of the laser Raman microscope.
  • the intensity of the laser light source of the laser Raman microscope at the time of measurement is weak enough not to cause deterioration of the sample during measurement, and it can be arbitrarily set within the range where a Raman spectrum can be obtained from several seconds to several tens of minutes of exposure time. ..
  • a hollow fiber membrane is embedded in ice, and a cross section is prepared with a microtome. Immerse the prepared cross-section sample in water (so that it swells in water), and make the cross-section slightly protrude from the water surface (see Fig. 7).
  • mapping a method of measuring the Raman spectrum within a set range by scanning the laser light collected in spots
  • imaging measurement A method of measuring the Raman spectrum in a set range by scanning a laser beam focused in a line
  • Raman spectrum peak intensity of the maximum peak in Raman spectrum
  • the measurement is carried out at a plurality of locations in the thickness direction on the cross section of the hollow fiber membrane.
  • Maximum peak in each of Ramansu Bae vector measured for the calculation of the Raman value is, for example, wavelength 2 9 3 5_Rei - peaks corresponding to the extensor contraction vibration of 1 near CH (carbon monohydrogen bond) Is the highest peak (see Fig. 9).
  • the peak intensity can be calculated from the peak area or peak height of the selected peak.
  • FIG. 10 shows an example of a peak intensity ratio graph.
  • the X axis indicates the position in the film thickness direction (direction of the arrow in Fig. 8) in the film cross section, and the vertical axis indicates the peak intensity ratio.
  • the peak intensity ratio shown in Fig. 10 is derived from the polymer ( ⁇ ) that constitutes the hollow fiber membrane. It is the intensity ratio of the nearby peaks (see Fig. 9), and the peak intensity ratio correlates with the polymer density.
  • the rate of change in the value between adjacent points (peak intensity ratio) measured at one interval including the maximum value of the peak intensity ratio (100%) was 5%
  • the part within (absolute value) is the film part (the part indicated by the solid arrow in Fig. 8), and the part outside 5% is the part other than the film (the part hatched in Fig. 10). Judgment is made and the data other than the membrane is deleted.
  • the inner shape of the hollow fiber membrane in cross section is preferably triangular.
  • the triangular shape means a shape close to a triangle, and is a concept including a shape such as a rice ball shape (rice ball shape) and a Reuleaux triangle in which the sides are not straight and there is no corner (Patent Document 6: International See Publication No. 201/1/2 2 6 7 3).
  • the ratio of the film thickness near the apex of the triangle (the thinnest film thickness) to the film thickness near the sides of the triangle (the thinnest film thickness) (the thinnest film thickness/the thickest film thickness) is preferably 0.6. It is 5 to 0.90. If the ratio is less than 0.65, the thinnest film may be too thin and may be easily deformed (crushed). On the other hand, when the ratio is larger than 0.90, the inner shape of the cross section of the film approaches a circle, so that it is difficult to obtain the effect of suppressing crushing in long-term use.
  • FIG. 11 showing a cross section of the hollow fiber membrane.
  • three triangular vertices are designated as 3, 13, and ⁇ , respectively, and three sides of the triangle connecting the three points with straight lines are designated as 313, 130, and ⁇ 3, respectively.
  • Perpendicular 3 from point 3 to side 130 Draw a vertical line 3 The intersection point with the outer circumference of the cross section of the hollow fiber membrane on the extension of is 9 and.
  • the hollow fiber membrane has a roughly circular cross-sectional outer shape, and the hollow part has a (triangular) rice ball shape.As shown in Fig. 11, the thinnest film thickness is 3", and the sill 1 ⁇ ,
  • ⁇ ⁇ and the thickest film thickness ⁇ 19, eh .fi facing each other were measured by the cross-sectional photograph of the hollow fiber membrane, and the ratio of the thinnest film thickness/the thickest film thickness (of the three values Each, or their average value) can be calculated.
  • the material constituting the hollow fiber membrane is not particularly limited, but a material containing at least one of cellulose-based resin, polysulfone-based resin and polyamide-based resin is preferable, and cellulose-based resin and polysulfone-based resin are preferable. It is more preferable that the material includes at least one of the above.
  • the cellulose-based resin is preferably a cellulose acetate-based resin.
  • Cellulose acetate Cell-based resins are resistant to chlorine, which is a bactericide, and have the characteristic of suppressing the growth of microorganisms.
  • the cellulose acetate-based resin is preferably acetate acetate, and more preferably cellulose triacetate from the viewpoint of durability.
  • the polysulfone-based resin is preferably a polyethersulfone-based resin.
  • the polyether sulfone resin is preferably a sulfonated polyether sulfone.
  • the hollow fiber membrane examples include a membrane having a single layer structure.
  • the hollow fiber membrane has high structural homogeneity in the thickness direction.
  • the Raman value of the above-mentioned hollow fiber membrane is in a range of a predetermined value or more, or a scanning electron microscope with a magnification of 500 times (3 There is little change in the structure when the cross-section of the hollow fiber membrane is continuously observed in the direction of the membrane thickness using Mami IV!).
  • the present invention also relates to a method for producing a hollow fiber membrane for obtaining the above hollow fiber membrane.
  • the method for manufacturing a hollow fiber membrane of the present embodiment includes at least a spinning step and a post-treatment step.
  • the raw material solution 80 is discharged from the nozzle 8 1 into the coagulating liquid 91 via the aerial traveling section, and the coagulated product of the raw material solution is pulled out from the coagulating liquid, so that the hollow fiber type semi-permeable type A hollow fiber membrane that is a membrane is obtained.
  • pulling out of the hollow fiber membrane is performed by mouth rollers 8 2, 8 3, 8 4 and 8 5.
  • the pulling speed is the surface speed of the mouth roller 83.
  • the raw material solution is prepared by dissolving the raw material of the hollow fiber membrane (the material forming the hollow fiber membrane described above) ⁇ 2020/175 375 18 ⁇ (: 171-1? 2020 /007080
  • the solvent/non-solvent mass ratio in the raw material solution is preferably 50/50 to 70/30.
  • the solvent is a liquid that can dissolve the raw materials
  • the non-solvent is a liquid that does not dissolve the raw materials.
  • the concentration of the coagulating liquid [(N3 other than 3 + water)/mass ratio of the coagulating liquid] is preferably 10% to 60%, more preferably 20% to 50%. .. Further, the temperature of the solidified liquid is preferably 10 to 30 ° , and more preferably 10 to 25°0.
  • the draw ratio (draft ratio) is 2.1 to 5.0, and preferably 2.2 to 4.0.
  • the draw ratio is the drawing speed (the linear speed of the raw material solution discharged from the nozzle) (V.) at the discharge rate of the raw material solution at the outlet of the nozzle (the linear speed of the coagulated raw material solution). ) (V ratio c). It should be noted that Patent Documents 2 to 6 do not describe the draw ratio in the spinning step.
  • the hollow fiber membrane 86 obtained in the spinning step is washed with water and then subjected to hot water treatment and salting treatment.
  • the hollow fiber membrane 86 is immersed in hot water 92.
  • the temperature of the hot water 92 in the hot water treatment is preferably not less than 86 ° ⁇ and less than 100 ° ⁇ , more preferably 90 to 99.5 ° ⁇ , More preferably 95-
  • the hot water treatment is preferably performed on the hollow fiber membranes 86 in a tension-free state.
  • the hot water treatment time is preferably 5 to 120 minutes, and more preferably 10 to 40 minutes.
  • the hollow fiber membrane 86 after hot water treatment is immersed in salt water 93. brine ⁇ 2020/175 375 19 ⁇ (:171? 2020 /007080
  • the 93 is an aqueous solution containing chloride ions.
  • the salt water 93 include aqueous solutions of sodium chloride (salt), potassium chloride, magnesium chloride, calcium chloride, lithium chloride and the like.
  • the concentration of the salt water 93 is preferably 0.5 to 20% by mass, and more preferably 1.0 to 10% by mass.
  • the temperature of the salt water 93 (the temperature of the salting treatment) is preferably 70°° or more and 95°° or less, more preferably 75°° or more and 90°° or less.
  • the time for the salting treatment is preferably 1 to 60 minutes, more preferably 5 to
  • the salting treatment is preferably performed on the hollow fiber membranes 86 in a tension-free state.
  • the effect of suppressing the I-portion shrinkage of the hollow fiber membrane is achieved by increasing the structural homogeneity of the hollow fiber membrane in the thickness direction.
  • the ratio (solvent/non-solvent ratio), draft ratio, and salting treatment (and hot water treatment) conditions may be changed.
  • the desolvation rate becomes slower, and the nucleus growth of the precipitated polymer becomes more uniform, so the polymer density of the film becomes It is considered to homogenize in the direction.
  • the pores shrink due to dehydration from the film by the salting treatment following the hot water treatment, and the homogenization of polymer density and the enhancement of strength are promoted.
  • the present invention also relates to a membrane separation method using the above hollow fiber membrane module 1.
  • a concentrated liquid concentrated first liquid
  • a diluting liquid diluted second liquid
  • the first liquid is caused to flow into the first chamber 11 at a predetermined pressure and the second liquid is supplied to the hollow fiber membrane module 1 at a pressure lower than the predetermined pressure.
  • the solvent contained in the first liquid in the first chamber 11 is transferred to the second liquid in the second chamber 12 via the hollow fiber membrane, and the first chamber 1 1 Drain the concentrated liquid from and the diluted liquid from the second chamber 1 2.
  • the osmotic pressure difference between the first and second liquids is 4 ! ⁇ /1 ⁇ 2020/175 375 20 (:171? 2020/007080
  • the first chamber 11 is outside the hollow fiber membrane and the second chamber 12 is inside the hollow fiber membrane.
  • 11 may be inside the hollow fiber membrane and the second chamber 12 may be outside the hollow fiber membrane.
  • the present invention also relates to the above hollow fiber membrane used in the above membrane separation method.
  • the hollow fiber membrane of Example 1 was produced under the following conditions by the method for producing a hollow fiber membrane described in the embodiment.
  • Non-solvent ethylene glycol (Mix ⁇ )
  • the viscometer coefficient was calculated from the following formula by measuring the flow-down time (360) in the same operation as above using a standard solution for viscometer calibration.
  • Viscometer coefficient [Absolute viscosity of standard solution (01 ?3 3) X density of solution (1.235 9/ ⁇ 3 )] / [Density of standard solution (9/ ⁇ 01 3 ) X Flow time of standard solution ( 360)]]
  • Discharge temperature of raw material solution 1 5 1 ° ⁇
  • Nozzle for discharge 3-split nozzle (Nozzle cross-sectional area: 0.05 1 0 1 2 )
  • the cross-sectional area of the nozzle is the cross-sectional area of the raw material solution discharge hole at the tip of the nozzle.
  • Non-solvents other than water N3
  • Mass ratio of solvent/non-solvent other than water (3/N3 other than water) in coagulation liquid Same as 3/3 of raw material solution shown in Table 1.
  • Example 1 As shown in Table 1, the conditions for salting treatment (concentration of saline solution, temperature) were changed. Otherwise in the same manner as in Example 2, the hollow fiber membranes of Examples 3 to 6 were produced.
  • Example 7 As shown in Table 1, The ratio has changed.
  • a hollow fiber membrane of Example 7 was produced in the same manner as in Example 2 except for the above.
  • Example 2 As shown in Table 1, the draw ratio ( ⁇ residence time) in the spinning process was changed. Otherwise in the same manner as in Example 2, the hollow fiber membrane of Example 8 was produced. Note that changing the draw ratio, the cross-sectional area of the nozzle opening 0.0 5_Rei_1_rei_1 change 2 0. 0 7 2 (by increasing the outside diameter and Suritsu-wide nozzle
  • Example 9 As shown in Table 1, The coagulation conditions, hot water treatment conditions, and salt treatment conditions were changed.
  • the hollow fiber membrane of Example 9 was produced in the same manner as Example 8 except for the above.
  • Example 10 As shown in Table 1, the polymer concentration of the raw material solution and the coagulation conditions were changed. Otherwise in the same manner as in Example 9, the hollow fiber membrane of Example 10 was produced. ⁇ 2020/175 375 23 ⁇ (: 171-1? 2020 /007080
  • a hollow fiber membrane of Comparative Example 1 was produced in the same manner as in Example 1 except that the salting treatment was not performed.
  • Example 1 As shown in Table 1, the draw ratio in the spinning process was changed.
  • a hollow fiber membrane of Comparative Example 2 was produced in the same manner as in Example 1 except for the above.
  • change the draw ratio change the cross-sectional area of the nozzle from 0.05 ⁇ 1111 2 to 0.04 ⁇ 1111 2 (By reducing the outer diameter and slit width of the nozzle, the nozzle opening ( The cross-sectional area of the raw material solution discharge hole) was reduced).
  • Comparative Example 4 As shown in Table 1, The coagulation conditions, draw ratio and hot water treatment conditions were changed. A hollow fiber membrane of Comparative Example 4 was produced in the same manner as in Comparative Example 1 except for the above.
  • Raman values of the hollow fiber membranes of Examples 1 to 10 and Comparative Examples 1 to 6 were measured.
  • the Raman value is measured under the following conditions by the measuring method described in the embodiment. It was Table 1 shows the Raman measurement results.
  • a hollow fiber membrane was embedded in ice and a cross section was prepared with a microtome.
  • the prepared cross section The sample was immersed in water, and the cross section was slightly exposed from the surface of the water.
  • a Raman microscope nanophoton laser Raman microscope: RAMAN— 11
  • laser wavelength 532 nm laser Intensity of about 2.2 mW
  • aperture diameter 100 Mm
  • exposure time 8 seconds
  • number of exposures 1 time diffraction grating 60 O gr/mm
  • objective lens 50x/NA 0.55 scan interval 1.0 Mm Mapping analysis (measurement of Raman spectrum) was performed.
  • the Raman value may be measured at any part of the film cross section (thin or thick part), but it was measured at the thickest part (center part of the side of the rice ball).
  • the intensity of the peak in the vicinity of 2935 cm- 1 in the Raman spectrum was calculated using the peak area calculation software attached to the micro Raman spectroscope. And 2800 ⁇ 3 1 00 c m- 1 the baseline, centered on top of the peak, to fix the width of the peak 22. to 2 c m-1, not to put a fitting with a mouth Rentsu function was calculated The peak area was used as the signal intensity (peak intensity) (see Fig. 9).
  • the outer diameter ( ⁇ D ), inner diameter (D) and hollow ratio (H) were measured as follows.
  • the ODs of the hollow fiber membranes of Examples 1 to 10 and Comparative Examples 1 to 6 were 200 Mm, 0 was 9001, and H was 20.3%.
  • the projector N ikon P RO FILEP RO ⁇ 2020/175 375 25 ⁇ (: 171-1? 2020 /007080
  • Photographs of cross-sections of hollow fiber membranes were taken using a microscope ⁇ Minami V 1 ⁇ 1 V V 1 ⁇ 1 _ 1_100, and the area measurement function of the above-mentioned microscope was used to measure the hollow portion of the hollow fiber membrane.
  • the cross-sectional area (hollow portion cross-sectional area) and the cross-sectional area of the membrane portion of the hollow fiber membrane (hollow portion cross-sectional area) were obtained, and the hollow ratio was calculated from the following formula.
  • Hollow ratio (%) hollow area cross-sectional area / (membrane cross-sectional area + hollow area cross-sectional area) X I 0 0
  • the inner diameter shrinkage ratio was measured as follows. Table 1 shows the measurement results of inner diameter shrinkage.
  • a plurality of hollow fiber membranes are bundled and packed so that the filling rate becomes 25.0 ⁇ 1.0%, and the hollow fiber membrane bundle and the end of the tube 3 II 3 are adhered with resin, and the adhesive resin end
  • the hollow fiber membrane module 1 was prepared by cutting the hollow fiber membrane to open the hollow portion of the hollow fiber membrane.
  • the manufactured hollow fiber membrane module 1 had no leak. Specifically, the hollow fiber membrane module 1 is submerged in water, the outside of the hollow fiber membrane is pressurized with air from one opening, and the other opening outside the hollow fiber membrane is sealed. If no air came out from the opening, it was judged that there was no leak.
  • a performance ([3 ⁇ 4 performance) confirmation test was performed on the manufactured hollow fiber membrane module 1. Specifically, using the hollow fiber membrane module 1, [3 ⁇ 4 ⁇ test (pressure on the outside of the hollow fiber membrane: 5. Of the test solution at the inlet 1 0 1 3 outside the hollow fiber membrane I concentration: 350 0 9 / 1_, temperature of target solution: 25 ° ⁇ , recovery ⁇ 2020/175 375 26 ⁇ (: 171-1? 2020 /007080
  • the permeated water amount ([3 ⁇ 4) and the salt removal rate ([3 ⁇ 4]) did not deviate from the performance standard of the hollow fiber membrane (! 1 ).
  • a standard reverse osmosis membrane As a standard, More than a day.
  • the hollow fiber membrane module 1 (a module in which the hollow fiber membrane is housed in a container made of 3 II 3 as shown in Fig. 5) was confirmed to have no performance problems as described above. Then, a test was conducted to carry out the predetermined membrane separation method described in the embodiment.
  • Liquid chromatography pumps 3 2 and 3 3 were used for feeding the liquid inside and outside the hollow fiber membrane.
  • the pressure at the inlet (second liquid inlet 1 0 1 3) inside the hollow fiber membrane is ⁇ .
  • the flow rate at the inlet (first liquid supply port 103) outside the hollow fiber membrane is 1 pressure is 5.
  • the operating conditions of pumps 3 2 and 3 3 were set so that
  • the two liquids are the same liquid, and the osmotic pressure difference between them is 0 1 ⁇ /1 3 ).
  • the concentration of the liquid in tank 34 is adjusted to 10% by mass, and 10% from the start of pump operation. Concentrated salt water was added to the tank 34 by the minute, and the concentration of the liquid in the tank 34 was adjusted to 15% by mass. The time when the amount reached 15% by mass was set as 0 hour (at the beginning of the test), and the test was continuously carried out (3 tests were carried out.
  • the pressure at the inlet 1 0 1 3) is maintained at 0.1 IV! 3 and the pressure at the outlet (first liquid outlet 1 0 13) outside the hollow fiber membrane is 0.
  • the temperature of the liquid in tank 34 was maintained at 25 ⁇ 1 ° . If the temperature changes greatly, the flow rate changes, which is not preferable.
  • the inner diameter shrinkage ratio of the hollow fiber membrane was measured after 1, 2, 4, 48, 72 and 96 hours from the start of the test. Specifically, at each time, the flow rate at the inflow port 10 13 inside the hollow fiber membrane and the flow rate at the outflow port 10 11 13 were measured, and the flow rate at the inflow port 10 13 inside the hollow fiber membrane was measured. Calculate the average value (the average flow rate in the hollow fiber membrane) of the flow rate at the outlet and the outlet 101.
  • FIG. 4 is a graph showing the relationship between the elapsed time from the start of the test and the change ratio of the average flow rate in the hollow fiber membranes of the hollow fiber membranes of Examples 1 and 2 and Comparative Example 2.
  • the inner diameter of the hollow fiber membrane 1 hour after the start of the test was used as the standard for the reduction rate because it is considered that the concentration distribution in the membrane is sufficiently stable after 1 hour.
  • Mitsumi (3 The inner diameter of the hollow fiber membrane 1 hour after the start of the test was regarded as the inner diameter at the start of use of the hollow fiber membrane.
  • the inner diameter (I 0) shrinkage ratio was calculated from the decrease rate of the average flow rate in the hollow fiber membrane from the ⁇ 96010 ⁇ 61 ⁇ equation.
  • Table 1 shows the flow rates and pressures at the inner and outer inlets of the hollow fiber (membrane) after 240 hours, and the required flow rate inside the hollow fiber (membrane). The energy (ratio to Comparative Example 1) is also shown.
  • 6 2 Holding member 6 2 3 o ring, 6 1 resin wall, 7 pressure vessel, 8 0 raw material solution, 8 1 nozzle, 8 2 ,8 3 ,8 4 ,8 5 mouth roller, 8 6 hollow fiber membrane, 9 1 coagulation liquid, 9 2 hot water, 9 3 brine.

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  • Chemical Kinetics & Catalysis (AREA)
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Abstract

A hollow fiber membrane that is a hollow-fiber-type semi-permeable membrane. The shrinkage rate of the inner diameter of the hollow fiber membrane after usage for 96 hours in a prescribed membrane separation method is 0.1% or more and less than 9% of the inner diameter at the start of usage. In the prescribed membrane separation method, a hollow fiber membrane module having the hollow fiber membrane and a first chamber and a second chamber partitioned by the hollow fiber membrane is used to cause a first liquid to flow into the first chamber at a first pressure and a second liquid to flow into the second chamber at a second pressure lower than the first pressure, whereby water included in the first liquid in the first chamber is transferred via the hollow fiber membrane to the second liquid in the second chamber, a concentrated liquid which is the concentrated first liquid is discharged from the first chamber, and a diluted liquid which is the diluted second liquid is discharged from the second chamber. An outer space of the hollow fiber membrane is the first chamber and an inner space of the hollow fiber membrane is the second chamber. The first pressure is 5.0 MPa, the second pressure is constant, and the osmotic pressure difference between the first liquid and the second liquid is 0 MPa.

Description

明 細 書 Specification
発明の名称 : Title of invention:
中空糸膜、 中空糸膜の製造方法、 中空糸膜モジュール、 膜分離装置および 膜分離方法 Hollow fiber membrane, hollow fiber membrane production method, hollow fiber membrane module, membrane separation device and membrane separation method
技術分野 Technical field
[0001] 本発明は、 中空糸膜、 中空糸膜の製造方法、 中空糸膜モジュール、 膜分離 装置および膜分離方法に関する。 The present invention relates to a hollow fiber membrane, a method for producing a hollow fiber membrane, a hollow fiber membrane module, a membrane separation device, and a membrane separation method.
背景技術 Background technology
[0002] 例えば、 海水から淡水を生産する場合、 RO法が用いられる。 RO法では 、 高圧ポンプによって浸透圧より高い所定の圧力に昇圧された海水を逆浸透 ( R 0 : Reverse Osmosis) モジュールに供給し、 RO膜を通過させること で、 海水中の塩分等を除去して淡水を取り出す。 残りの海水は、 濃縮塩水 ( ブライン) として R〇モジュールから排出される。 [0002] For example, when producing fresh water from seawater, the RO method is used. In the RO method, seawater, which has been pressurized to a predetermined pressure higher than the osmotic pressure by a high-pressure pump, is supplied to the reverse osmosis (R 0: Reverse Osmosis) module and passed through the RO membrane to remove salts, etc. in seawater. Take out fresh water. The rest of the seawater is discharged from the RO module as concentrated brine (brine).
[0003] 近年、 海水淡水化プラントのプライン (濃縮海水) に関する規制が強化さ れ、 ブラインを如何に処理するかを考える必要がある。 その手法の一つとし て、 ブラインを減容するために、 プラインコンセントレーシヨン (BC) 法 を用いることが検討されている。 BC法は、 このようなプラインや排水の減 容、 Z L D (Zero Liquid Discharge) 、 対象溶液中からの有価物の回収な どへの適用が期待されている。 [0003] In recent years, regulations on the line (concentrated seawater) of seawater desalination plants have been tightened, and it is necessary to consider how to treat brine. As one of the methods, it is considered to use the Plan Concentration (BC) method to reduce the volume of brine. The BC method is expected to be applied to such reduction of plumes and wastewater, ZLD (Zero Liquid Discharge), and recovery of valuable materials from the target solution.
[0004] BC法は、 RO法よりも必要なエネルギーが少ない方法である。 BC法と しては、 例えば、 特許文献 1 (特開 201 8- 1 1 1 1号公報) に、 中空糸 膜モジュールの一方の第 1室に対象溶液の一部を流し、 他方の第 2室に対象 溶液の他の一部を流して、 第 1室内の対象溶液を加圧することで、 第 1室内 の対象溶液に含まれる水を中空糸膜を介して第 2室内に移行させ、 第 1室内 の対象溶液を濃縮し、 第 2室内の対象溶液を希釈する膜分離方法が開示され ている。 [0004] The BC method requires less energy than the RO method. As the BC method, for example, in Patent Document 1 (Japanese Unexamined Patent Publication No. 20108-1111), a part of the target solution is caused to flow into one of the first chambers of the hollow fiber membrane module, and the other of the second chamber is used. By flowing another part of the target solution into the chamber and pressurizing the target solution in the first chamber, the water contained in the target solution in the first chamber is transferred to the second chamber through the hollow fiber membrane, A membrane separation method is disclosed in which the target solution in one chamber is concentrated and the target solution in the second chamber is diluted.
[0005] RO法のように、 対象溶液が加圧される中空糸膜の一方側 (高圧側) だけ \¥0 2020/175375 2 卩(:17 2020 /007080 [0005] Like the RO method, only one side (high pressure side) of the hollow fiber membrane to which the target solution is pressurized \\0 2020/175 375 2 (: 17 2020 /007080
に浸透圧を有する対象溶液を供給する場合、 中空糸膜の他方側は基本的に浸 透圧を有さない水だけであるため、 中空糸膜の両側間の浸透圧差が大きく、 これにより生じる圧力に打ち勝つ高い圧力で対象溶液を加圧する必要がある 。 そして、 加圧の圧力は、 中空糸膜の運転圧力 (限界圧力) や使用するボン プの最大圧力によって制限されるため、 [¾〇法では、 対象溶液の浸透圧が中 空糸膜の運転圧力やポンプの最大圧力等を超えるような高濃度まで、 対象溶 液を濃縮することはできない。 When the target solution with osmotic pressure is supplied to the hollow fiber membrane, the other side of the hollow fiber membrane is basically water without osmotic pressure. It is necessary to pressurize the target solution with a high pressure that overcomes the pressure. Since the pressurization pressure is limited by the operating pressure (limit pressure) of the hollow fiber membrane and the maximum pressure of the pump to be used, [In method Ⅲ, the osmotic pressure of the target solution is the operating pressure of the hollow fiber membrane. The target solution cannot be concentrated to a high concentration that exceeds the pressure or the maximum pressure of the pump.
[0006] これに対して、 巳(3法では、 中空糸膜の他方側 (低圧側) にも対象溶液を 流すことで、 中空糸膜の両側間の浸透圧差を低減し、 高圧側の対象溶液への 加圧の圧力を低減することができる。 このため、 巳〇法を用いることで、 対 象溶液の浸透圧が中空糸膜の運転圧力やポンプの最大圧力等を超えるような 高濃度まで、 対象溶液を濃縮することが可能となる。 したがって、 巳(3法に よれば、 ブラインのような高濃度溶液の濃縮 (膜分離) が可能である。 [0006] On the other hand, by applying the target solution to the other side (low pressure side) of the hollow fiber membrane in method 3, the osmotic pressure difference between both sides of the hollow fiber membrane is reduced, and the target solution on the high pressure side is reduced. Therefore, it is possible to reduce the pressure applied to the solution.Therefore, by using the method M, it is possible to increase the concentration of the solution such that the osmotic pressure of the solution exceeds the operating pressure of the hollow fiber membrane or the maximum pressure of the pump. Therefore, it is possible to concentrate the solution of interest.(3) According to method 3, it is possible to concentrate (membrane separation) a highly concentrated solution such as brine.
[0007] 一方、 特許文献 2〜 6には、 原料溶液をノズルから空中走行部を経て凝固 液中に吐出して凝固させ、 凝固物を凝固液中から順次曳き出すことにより、 中空糸膜を得る工程 (紡糸工程) と、 紡糸工程で得られた中空糸膜を水洗し た後に、 熱水処理および塩漬処理の少なくともいずれかに供する工程 (後処 理工程) と、 を含む中空糸膜の製造方法が開示されている。 [0007] On the other hand, in Patent Documents 2 to 6, a raw material solution is discharged from a nozzle through an in-air traveling portion into a coagulating liquid to be coagulated, and the coagulated product is sequentially pulled out from the coagulating liquid to form a hollow fiber membrane. A hollow fiber membrane comprising a step of obtaining (spinning step), and a step of washing the hollow fiber membrane obtained in the spinning step with water and then subjecting it to at least one of hot water treatment and salting treatment (post-treatment step). Is disclosed.
先行技術文献 Prior art documents
特許文献 Patent literature
[0008] 特許文献 1 :特開 2 0 1 8 _ 1 1 1 1号公報 [0008] Patent Document 1: Japanese Patent Laid-Open No. 2018_1111
特許文献 2 :国際公開第 2 0 1 2 / 0 2 6 3 7 3号 Patent Document 2: International Publication No. 2 0 1 2/0 2 6 3 7 3
特許文献 3 :国際公開第 2 0 1 3 / 1 1 8 8 5 9号 Patent Document 3: International Publication No. 2 0 1 3/1 1 8 8 5 9
特許文献 4 :国際公開第 2 0 1 3 / 1 2 5 6 8 1号 Patent Document 4: International Publication No. 2 0 1 3/1 2 5 6 8 1
特許文献 5 :特開 2 0 1 3 _ 1 9 8 8 9 3号公報 Patent Document 5: JP 2 0 1 3 _ 1 9 8 8 9 3 Publication
特許文献 6 :国際公開第 2 0 1 7 / 1 2 2 6 7 3号 発明の概要 〇 2020/175375 3 卩(:171? 2020 /007080 発明が解決しようとする課題 Patent Document 6: International Publication No. 2 0 1 7/1 2 2 6 7 3 Summary of Invention 〇 2020/175375 3 卩(:171? 2020/007080 Issues to be solved by the invention
[0009] 巳(3法では、 [¾ 0法とは異なり、 中空糸膜の内側と外側の両方に液を積極 的に送り込む必要があるため、 巳(3法に用いられる中空糸膜は、 [¾〇法に用 いられる通常の中空糸膜 ([¾〇膜) より内径 (丨 口) を大きく して、 中空糸 膜の内側の圧力損失を低下させることが望ましい。 しかし、 本発明者らは、 通常の 8 0膜より内径 (丨 口) が大きい中空糸膜は、 巳(3法による膜分離に 用いられたときに、 中空糸膜の内径が経時的に減少することを見出した。 [0009] In the method (3, unlike the method ¾, it is necessary to positively feed the liquid to both the inside and the outside of the hollow fiber membrane. Therefore, the method (3) [It is desirable that the inner diameter (head) be made larger than that of a normal hollow fiber membrane ([¾ membrane] used in the method III to reduce the pressure loss inside the hollow fiber membrane. Et al. found that hollow fiber membranes with an inner diameter (head) larger than that of a normal 80 membrane decreased the inner diameter of the hollow fiber membrane with time when used for membrane separation by the method (3). ..
[0010] 中空糸膜の内径が経時的に減少すると、 中空糸膜の内側へ通水するための 運転エネルギーが経時的に増大するという問題がある。 また、 巳(3法を用い た処理は、 他の処理と組み合わせたシステムの一部として用いられることが 多いため、 中空糸膜の内径が経時的に減少すると、 システム全体の制御が困 難になるという問題もある。 [0010] When the inner diameter of the hollow fiber membrane decreases with time, there is a problem that operating energy for passing water to the inside of the hollow fiber membrane increases with time. In addition, since the treatment using the method (3) is often used as part of a system that is combined with other treatments, if the inner diameter of the hollow fiber membrane decreases over time, it becomes difficult to control the entire system. There is also the problem of becoming.
[001 1 ] したがって、 本発明は、 中空糸膜が巳(3法による膜分離に用いられたとき に、 中空糸膜の内径の経時的な減少を抑制することを目的とする。 [001 1] Therefore, an object of the present invention is to suppress the decrease in the inner diameter of the hollow fiber membrane over time when the hollow fiber membrane is used for membrane separation by the method (3).
課題を解決するための手段 Means for solving the problem
[0012] (1) 中空糸型の半透膜である中空糸膜であって、 (1) A hollow fiber membrane which is a hollow fiber type semipermeable membrane,
所定の膜分離方法に 9 6時間使用された後の前記中空糸膜の内径の収縮率 が、 使用開始時の内径に対して〇. 1 %以上 9 %未満であり、 The shrinkage ratio of the inner diameter of the hollow fiber membrane after being used for a predetermined membrane separation method for 96 hours is ≧0.1% and less than 9% with respect to the inner diameter at the start of use,
前記所定の膜分離方法は、 前記中空糸膜と、 前記中空糸膜で仕切られた第 1室および第 2室と、 を有する中空糸膜モジュールを用いて、 第 1液を第 1 圧力で前記第 1室に流し、 第 2液を前記第 1圧力よりも低い第 2圧力で前記 第 2室に流すことで、 前記第 1室内の前記第 1液に含まれる溶媒を前記中空 糸膜を介して前記第 2室内の前記第 2液に移行させ、 前記第 1室から濃縮さ れた前記第 1液である濃縮液を排出し、 前記第 2室から希釈された前記第 2 液である希釈液を排出し、 The predetermined membrane separation method uses a hollow fiber membrane module having the hollow fiber membrane and a first chamber and a second chamber partitioned by the hollow fiber membrane, and the first liquid is subjected to the first pressure at the first pressure. By flowing into the first chamber and flowing the second liquid into the second chamber at a second pressure lower than the first pressure, the solvent contained in the first liquid in the first chamber is passed through the hollow fiber membrane. To transfer to the second liquid in the second chamber, discharge the concentrated liquid that is the first liquid concentrated from the first chamber, and dilute the second liquid diluted from the second chamber. Drain the liquid,
前記中空糸膜の外側の空間が前記第 1室であり、 前記中空糸膜の内側の空 間が前記第 2室であり、 The outer space of the hollow fiber membrane is the first chamber, the inner space of the hollow fiber membrane is the second chamber,
前記第 1圧力が 5 .
Figure imgf000005_0001
前記第 2圧力が一定であり、 〇 2020/175375 4 卩(:171? 2020 /007080
The first pressure is 5.
Figure imgf000005_0001
The second pressure is constant, 〇 2020/175 375 4 卩 (: 171-1? 2020 /007080
前記第 1液と前記第 2液の浸透圧差が 0 !\/1 3である、 中空糸膜。 A hollow fiber membrane, wherein the osmotic pressure difference between the first liquid and the second liquid is 0 !\/1 3 .
[0013] (2) 前記中空糸膜の内径が 4 0 以上 2 0 0 以下である、 (1 (2) The inner diameter of the hollow fiber membrane is 40 or more and 200 or less, (1
) に記載の中空糸膜。 ) The hollow fiber membrane according to.
[0014] (3) 前記中空糸膜のラマン値が 7 2 %以上 9 0 %以下である、 (1) または (2) に記載の中空糸膜。 (3) The hollow fiber membrane according to (1) or (2), wherein the hollow fiber membrane has a Raman value of 72% or more and 90% or less.
[0015] (4) 前記中空糸膜の断面内形が三角形状である、 (1) 〜 (3) のい ずれかに記載の中空糸膜。 (4) The hollow fiber membrane according to any one of (1) to (3), wherein the hollow fiber membrane has a triangular cross-section.
[0016] (5) セルロース系樹脂、 ポリスルホン系樹脂およびポリアミ ド系樹脂 の少なくともいずれかを含む材料から構成される、 (1) 〜 (4) のいずれ かに記載の中空糸膜。 (5) The hollow fiber membrane according to any one of (1) to (4), which is composed of a material containing at least one of a cellulose resin, a polysulfone resin, and a polyamide resin.
[0017] (6) 前記中空糸膜と、 前記中空糸膜で仕切られた第 1室および第 2室 と、 を有する中空糸膜モジユールを用いて、 第 1液を第 1圧力で前記第 1室 に流し、 第 2液を前記第 1圧力よりも低い第 2圧力で前記第 2室に流すこと で、 前記第 1室内の前記第 1液に含まれる溶媒を前記中空糸膜を介して前記 第 2室内の前記第 2液に移行させ、 前記第 1室から濃縮された前記第 1液で ある濃縮液を排出し、 前記第 2室から希釈された前記第 2液である希釈液を 排出し、 前記第 1液と前記第 2液の浸透圧差が 4 IV! 3以下である、 膜分離 方法に用いられる、 (1) 〜 (5) のいずれかに記載の中空糸膜。 (6) A hollow fiber membrane module having the hollow fiber membrane and a first chamber and a second chamber partitioned by the hollow fiber membrane is used to apply the first liquid to the first pressure at the first pressure. By flowing the second liquid into the second chamber at a second pressure lower than the first pressure, so that the solvent contained in the first liquid in the first chamber is passed through the hollow fiber membrane to Transfer to the second liquid in the second chamber, discharge the concentrated liquid that is the concentrated first liquid from the first chamber, and discharge the diluted liquid that is the diluted second liquid from the second chamber The hollow fiber membrane according to any one of (1) to (5), which is used in a membrane separation method in which the osmotic pressure difference between the first liquid and the second liquid is 4 IV! 3 or less.
[0018] (7) 原料溶液をノズルから空中走行部を経て凝固液中に吐出して、 前 記原料溶液の凝固物を前記凝固液中から曳き出すことにより、 中空糸型の半 透膜である中空糸膜を得る、 紡糸工程と、 [0018] (7) The raw material solution is discharged from the nozzle into the coagulating liquid through the air running portion, and the coagulated product of the raw material solution is pulled out from the coagulating liquid to form a hollow fiber type semipermeable membrane. To obtain a hollow fiber membrane, a spinning step,
前記紡糸工程で得られた中空糸膜を水洗した後に、 熱水処理および塩漬処 理に供する、 後処理工程と、 After washing the hollow fiber membrane obtained in the spinning step with water, it is subjected to hot water treatment and salting treatment, and a post-treatment step,
を含む中空糸膜の製造方法であって、 A method for producing a hollow fiber membrane comprising:
前記原料溶液は溶媒および非溶媒を含み、 前記原料溶液中の溶媒/非溶媒 の質量比が 5 0 / 5 0〜 7 0 / 3 0であり、 The raw material solution contains a solvent and a non-solvent, the mass ratio of the solvent / non-solvent in the raw material solution is 50/50 ~ 70 / 30,
前記紡糸工程において、 前記ノズルの出口における原料溶液の吐出速度に 対する曳き出し速度の比率である延伸倍率が 2 . 1〜 5 . 0であり、 〇 2020/175375 5 卩(:171? 2020 /007080 In the spinning step, the draw ratio, which is the ratio of the drawing speed to the discharge speed of the raw material solution at the outlet of the nozzle, is 2.1 to 5.0, 〇 2020/175 375 5 (:171? 2020/007080
前記塩漬処理の温度が 70°〇以上 95°〇以下である、 製造方法。 The manufacturing method, wherein the temperature of the salting treatment is not less than 70° and not more than 95°.
[0019] (8) (7) に記載の製造方法により製造される中空糸膜。 (8) A hollow fiber membrane produced by the production method described in (7).
[0020] (9) (1 ) 〜 (6) および (8) のいずれかに記載の中空糸膜と、 前 記中空糸膜で仕切られた第 1室および第 2室と、 を有する、 中空糸膜モジュ _ル。 [0020] (9) A hollow having a hollow fiber membrane according to any one of (1) to (6) and (8), and a first chamber and a second chamber partitioned by the hollow fiber membrane. Thread film module.
[0021] (1 0) (9) に記載の中空糸膜モジュールを備える膜分離装置であつ て、 [0021](10) A membrane separation device including the hollow fiber membrane module according to (9),
前記第 1液を第 1圧力で前記第 1室に流し、 前記第 2液を前記第 1圧力よ りも低い第 2圧力で前記第 2室に流すことで、 前記第 1室内の前記第 1液に 含まれる溶媒を前記中空糸膜を介して前記第 2室内の前記第 2液に移行させ 、 前記第 1室から濃縮された前記第 1液である濃縮液を排出し、 前記第 2室 から希釈された前記第 2液である希釈液を排出し、 By flowing the first liquid to the first chamber at a first pressure and the second liquid to the second chamber at a second pressure lower than the first pressure, the first liquid in the first chamber The solvent contained in the liquid is transferred to the second liquid in the second chamber through the hollow fiber membrane, and the concentrated liquid which is the concentrated first liquid is discharged from the first chamber, Discharge the diluted liquid which is the second liquid diluted from
前記第 1液と前記第 2液の浸透圧差が 4 IV! ? 3以下である、 膜分離装置。 The osmotic pressure difference of the first liquid and the second liquid is 4 IV!? 3 or less, the membrane separation apparatus.
[0022] (1 1 ) (9) に記載の中空糸膜モジュールを用いる膜分離方法であつ て、 [0022](1 1) A membrane separation method using the hollow fiber membrane module according to (9), comprising:
前記第 1液を第 1圧力で前記第 1室に流し、 前記第 2液を前記第 1圧力よ りも低い第 2圧力で前記第 2室に流すことで、 前記第 1室内の前記第 1液に 含まれる溶媒を前記中空糸膜を介して前記第 2室内の前記第 2液に移行させ 、 前記第 1室から濃縮された前記第 1液である濃縮液を排出し、 前記第 2室 から希釈された前記第 2液である希釈液を排出し、 By flowing the first liquid to the first chamber at a first pressure and the second liquid to the second chamber at a second pressure lower than the first pressure, the first liquid in the first chamber The solvent contained in the liquid is transferred to the second liquid in the second chamber through the hollow fiber membrane, and the concentrated liquid which is the concentrated first liquid is discharged from the first chamber, Discharge the diluted liquid which is the second liquid diluted from
前記第 1液と前記第 2液の浸透圧差が 4 IV! ? 3以下である、 膜分離方法。 発明の効果 Wherein the first liquid osmotic pressure of the second liquid is 4 IV!? 3 or less, membrane separation method. Effect of the invention
[0023] 本発明によれば、 中空糸膜が巳 (3法による膜分離に用いられたときに、 中 空糸膜の内径の経時的な減少を抑制することができる。 According to the present invention, when the hollow fiber membrane is used for membrane separation by the method ( 3), it is possible to suppress a decrease in the inner diameter of the hollow fiber membrane over time.
[0024] 中空糸膜の内径の経時的な減少を抑制することで、 中空糸膜の内側へ通水 するための運転エネルギーの増大を抑えることができる。 また、 巳〇法を用 いた処理が、 他の処理と組み合わせたシステムの一部として用いられる場合 において、 中空糸膜の内径の経時的な減少を抑制することで、 システム全体 〇 2020/175375 6 卩(:171? 2020 /007080 [0024] By suppressing the decrease in the inner diameter of the hollow fiber membrane with time, it is possible to suppress an increase in operating energy for passing water inside the hollow fiber membrane. In addition, when the treatment using the method is used as part of a system combined with other treatments, by suppressing the decrease in the inner diameter of the hollow fiber membrane over time, the entire system can be suppressed. 〇 2020/175375 6 卩 (: 171-1? 2020 /007080
の制御が容易になる。 Control becomes easier.
図面の簡単な説明 Brief description of the drawings
[0025] [図 1]実施形態 1の膜分離装置を示す模式図である。 [0025] [Fig. 1] Fig. 1 is a schematic view showing a membrane separation device of Embodiment 1.
[図 2]中空糸膜モジュールを示す模式図である。 [Fig. 2] A schematic view showing a hollow fiber membrane module.
[図 3]中空糸膜モジュールを示す概略断面図である。 FIG. 3 is a schematic cross-sectional view showing a hollow fiber membrane module.
[図 4]実施例 1、 2および比較例 2の中空糸膜について、 巳(3試験開始からの 経過時間と中空糸膜内の平均流量の変化比率との関係を示すグラフである。 [図 5]実施例において、 中空糸膜の内径の収縮率の測定に用いた巳(3試験の概 要を説明するための模式図である。 FIG. 4 is a graph showing the relationship between the elapsed time from the start of the test and the change rate of the average flow rate in the hollow fiber membranes of the hollow fiber membranes of Examples 1 and 2 and Comparative Example 2. 5] In the examples, a pattern used to measure the shrinkage ratio of the inner diameter of the hollow fiber membrane (a schematic diagram for explaining the outline of 3 tests.
[図 6]中空糸膜の製造方法の一例を説明するための模式図である。 FIG. 6 is a schematic diagram for explaining an example of a method for manufacturing a hollow fiber membrane.
[図 7]ラマン値の測定方法を説明するための模式図である。 [Fig. 7] Fig. 7 is a schematic diagram for explaining a method for measuring a Raman value.
[図 8]ラマン値の測定方法を説明するための模式図である。 [FIG. 8] A schematic diagram for explaining a method for measuring a Raman value.
[図 9]ラマン値の測定方法を説明するための模式図である。 [Fig. 9] Fig. 9 is a schematic diagram for explaining a method for measuring a Raman value.
[図 10]ラマン分光法による分析結果の一例を示すグラフである。 FIG. 10 is a graph showing an example of the analysis result by Raman spectroscopy.
[図 1 1]中空糸膜の最薄膜厚/最厚膜厚の算出方法を説明するための模式図で ある。 [Fig. 11] Fig. 11 is a schematic diagram for explaining a method of calculating the thinnest thickness/thickness of the hollow fiber membrane.
発明を実施するための形態 MODE FOR CARRYING OUT THE INVENTION
[0026] 本発明の実施形態について、 図面を参照して説明する。 なお、 図面におい て、 同 _の参照符号は、 同 _部分または相当部分を表すものである。 また、 長さ、 幅、 厚さ、 深さなどの寸法関係は図面の明瞭化と簡略化のために適宜 変更されており、 実際の寸法関係を表すものではない。 [0026] An embodiment of the present invention will be described with reference to the drawings. The drawings Te smell, the _ reference numerals, illustrates a same _ or corresponding parts. The dimensional relationships such as length, width, thickness, and depth have been changed as appropriate for the sake of clarity and simplification of the drawings, and do not represent actual dimensional relationships.
[0027] 以下では、 まず、 本発明の膜分離装置の実施形態について説明し、 後に、 膜分離装置に用いられる中空糸膜モジュールおよび中空糸膜について説明す る。 [0027] In the following, first, an embodiment of the membrane separation device of the present invention will be described, and subsequently, a hollow fiber membrane module and a hollow fiber membrane used in the membrane separation device will be described.
[0028] <膜分離装置 > [0028] <Membrane separation device>
図 1 を参照して、 本実施形態の膜分離装置は、 中空糸膜モジュール 1 を備 える。 中空糸膜モジュール 1は、 中空糸膜 1 〇と、 中空糸膜 1 0で仕切られ た第 1室 1 1および第 2室 1 2と、 を有する。 〇 2020/175375 7 卩(:171? 2020 /007080 Referring to FIG. 1, the membrane separation device of the present embodiment includes a hollow fiber membrane module 1. The hollow fiber membrane module 1 has a hollow fiber membrane 10 and a first chamber 11 and a second chamber 12 partitioned by the hollow fiber membrane 10. 〇 2020/175 375 7 (: 171-1? 2020 /007080
[0029] 本実施形態の膜分離装置は、 第 1液を第 1圧力で第 1室 1 1 に流し、 第 2 液を第 1圧力よりも低い第 2圧力で第 2室 1 2に流すことで、 第 1室 1 1内 の第 1液に含まれる溶媒を中空糸膜を介して第 2室 1 2内の第 2液に移行さ せ、 第 1室 1 1から濃縮液 (濃縮された第 1液) を排出し、 第 2室 1 2から 希釈液 (希釈された第 2液) を排出する。 このようにして、 第 1液を濃縮す ると共に、 第 2液を希釈することができる。 [0029] In the membrane separation device of the present embodiment, the first liquid is caused to flow into the first chamber 11 at the first pressure, and the second liquid is caused to flow into the second chamber 12 at the second pressure lower than the first pressure. Then, the solvent contained in the first liquid in the first chamber 11 was transferred to the second liquid in the second chamber 12 through the hollow fiber membrane, and the concentrated liquid (concentrated liquid was collected from the first chamber 11). The first liquid) is discharged, and the diluted liquid (diluted second liquid) is discharged from the second chamber 12. In this way, the first liquid can be concentrated and the second liquid can be diluted.
[0030] なお、 図 1では簡略化のために中空糸膜 1 0が平膜のように描かれている が、 本実施形態で用いられる中空糸膜は、 後述する図 2および図 3に示され るような中空糸型の半透膜 (中空糸膜 1 0) である。 中空糸膜は、 スパイラ ル型の半透膜などに比べて、 膜モジュールの容積当たりの膜面積を大きくす ることができ、 膜モジュールの容積当たりの膜透過流量を高めることができ る点で有利である。 中空糸膜モジュールは、 複数の中空糸膜を含み、 複数の 中空糸膜の各々は両端に開口部を有することが好ましい。 [0030] Although the hollow fiber membrane 10 is drawn like a flat membrane in FIG. 1 for simplification, the hollow fiber membrane used in this embodiment is shown in FIGS. 2 and 3 described later. It is a hollow fiber type semipermeable membrane (hollow fiber membrane 10). Hollow fiber membranes can increase the membrane area per volume of the membrane module and can increase the membrane permeation flow rate per volume of the membrane module compared to a spiral type semipermeable membrane. It is advantageous. The hollow fiber membrane module includes a plurality of hollow fiber membranes, and each of the plurality of hollow fiber membranes preferably has openings at both ends.
[0031] 中空糸膜モジュール 1 において、 第 1室 1 1は中空糸膜の外側であり、 第 [0031] In the hollow fiber membrane module 1, the first chamber 11 is outside the hollow fiber membrane, and
2室 1 2は中空糸膜の内側であることが好ましい。 すなわち、 中空糸膜の外 側の溶液が内側の溶液よりも加圧されることが好ましい。 中空糸膜の内側 ( 中空部) を流れる溶液を加圧しても、 圧力損失が大きくなり加圧が十分に行 われ難い場合があるほか、 中空糸膜自体の構造が、 外圧に対して構造を保持 しやすく、 高い内圧を付与すると膜が破裂する可能性があるからである。 し かしながら、 圧力損失が小さい、 つまり大きな内径を持ち、 内圧に対する耐 圧が大きい中空糸膜を使用する場合は、 第 1室 1 1 を中空糸膜の内側として も、 特に問題はない。 ただし、 上述の中空糸膜の内径収縮率を測定するとき に用いられる中空糸膜モジュールは、 第 1室 1 1が中空糸膜の外側であり、 第 2室 1 2が中空糸膜の内側である。 The two chambers 12 are preferably inside the hollow fiber membrane. That is, the solution on the outer side of the hollow fiber membrane is preferably pressurized more than the solution on the inner side. Even if the solution flowing inside the hollow fiber membrane (hollow part) is pressurized, the pressure loss may increase and it may be difficult to pressurize sufficiently. In addition, the structure of the hollow fiber membrane itself is This is because it is easy to hold and the membrane may burst if a high internal pressure is applied. However, when using a hollow fiber membrane with a small pressure loss, that is, a large inner diameter and a large pressure resistance against the internal pressure, there is no particular problem even if the first chamber 11 is inside the hollow fiber membrane. However, in the hollow fiber membrane module used to measure the inner diameter shrinkage of the hollow fiber membrane described above, the first chamber 11 is outside the hollow fiber membrane and the second chamber 12 is inside the hollow fiber membrane. is there.
[0032] 第 1液と第 2液の浸透圧差は、
Figure imgf000009_0001
以下である。 第 1液と第 2液の浸 透圧差は、 下記式で示される。
[0032] The osmotic pressure difference between the first liquid and the second liquid is
Figure imgf000009_0001
It is the following. The permeation pressure difference between the first and second liquids is shown by the following formula.
[浸透圧差] = [第 1液の浸透圧] 一 [第 2液の浸透圧] 上記式において、 「第 1液の浸透圧」 とは、 中空糸膜モジュール 1の第 1 〇 2020/175375 8 卩(:171? 2020 /007080 [Osmotic pressure difference] = [Osmotic pressure of the first liquid]-[Osmotic pressure of the second liquid] In the above formula, "osmotic pressure of the first liquid" means the first pressure of the hollow fiber membrane module 1. 〇 2020/175 375 8 (: 171-1? 2020 /007080
室 1 1 に供給される直前の第 1液の浸透圧であり、 「第 2液の浸透圧」 とは 、 中空糸膜モジュール 1の第 2室 1 2に供給される直前の第 2液の浸透圧で ある。 It is the osmotic pressure of the first liquid immediately before being supplied to the chamber 11, and the "osmotic pressure of the second liquid" is the osmotic pressure of the second liquid immediately before being supplied to the second chamber 12 of the hollow fiber membrane module 1. It is the osmotic pressure.
[0033] 上記浸透圧差が 4 IV! 3以下であるとの規定は、 浸透圧差が負 (マイナス ) の値である場合を含むことを意味する。 浸透圧差は、 好ましくは 3 . 5 IV! 3以下である。 [0033] The stipulation that the osmotic pressure difference is 4 IV! 3 or less means that the osmotic pressure difference has a negative (minus) value. The osmotic pressure difference is preferably 3.5 IV! 3 or less.
[0034] 第 1室 1 1 に流される第 1液の所定の圧力 (第 1圧力) は、 特に制限され ないが、 好ましくは 3〜 1 0 1\/1 3であり、 より好ましくは 5 ~ 8 . 5 1\/1 ^である。 [0034] The predetermined pressure (first pressure) of the first liquid flowing into the first chamber 11 is not particularly limited, but is preferably 3 to 101\/1 3, and more preferably 5 to 10. It is 8.5 1\/1^.
[0035] なお、 上記 「浸透圧差」 が下記式で示される 「第 1液と第 2液の圧力差」 よりも小さければ、 理論上、 巳〇法による膜分離は実施可能である。 「第 1 液と第 2液の圧力差」 に対する 「浸透圧差」 の比率は、 好ましくは 5 0 %以 下であり、 より好ましくは 3 0 %以下である。 なお、 「5 0 %以下」 および 「3 0 %以下」 との規定は、 浸透圧差の比率が負 (マイナス) の値である場 合を含む。 [0035] If the "osmotic pressure difference" is smaller than the "pressure difference between the first liquid and the second liquid" represented by the following formula, theoretically, the membrane separation by the method 裳 can be carried out. The ratio of the “osmotic pressure difference” to the “pressure difference between the first liquid and the second liquid” is preferably 50% or less, more preferably 30% or less. The provisions of "50% or less" and "30% or less" include cases where the ratio of the osmotic pressure difference is a negative value.
[第 1液と第 2液の圧力差] = [第 1液の圧力] — [第 2液の圧力] [Pressure difference between 1st liquid and 2nd liquid] = [Pressure of 1st liquid] — [Pressure of 2nd liquid]
[0036] このように、 プラインコンセントレーシヨン (巳〇) においては、 [¾〇法 のように対象液 (高浸透圧液) と淡水との間の高い浸透圧差に逆らって逆浸 透を起こさせるための高い圧力が必要なく、 比較的低圧の加圧によって、 対 象液の膜分離を実施することができる (第 1液を濃縮し、 第 2液を希釈する ことができる) 。 また、 巳〇を用いることで、 [¾〇法よりも高濃度の対象液 をさらに濃縮することも可能となる。 [0036] As described above, in the plan concentration (Mix), the reverse osmosis occurs against the high osmotic pressure difference between the target liquid (high osmotic liquid) and fresh water as in Method Ⅲ. It is possible to carry out membrane separation of the target liquid by pressurizing at a relatively low pressure (the first liquid can be concentrated and the second liquid can be diluted) without the need for high pressure to cause it. In addition, by using Mitsumi, it becomes possible to further concentrate the target liquid having a higher concentration than that of the method.
[0037] なお、 浸透圧差は 0 1\/1 3であってもよい。 また、 第 1液と第 2液は同じ 液であってもよく、 異なる液であってもよい。 また、 第 1液と第 2液の濃度 は、 有効な浸透圧を示す最低濃度以上飽和濃度以下である。 好ましくは 3 . [0037] The osmotic pressure difference may be 0 1 \/1 3. The first liquid and the second liquid may be the same liquid or different liquids. The concentrations of the 1st and 2nd liquids are above the minimum concentration and below the saturation concentration that show effective osmotic pressure. Preferably 3.
5 %以上飽和濃度以下であり、 より好ましくは 5 %以上飽和濃度以下である 5% or more and the saturation concentration or less, more preferably 5% or more and the saturation concentration or less
[0038] 膜分離装置は、 圧力低下装置として、 例えば、 高圧ポンプ 3 1 によって所 〇 2020/175375 9 卩(:171? 2020 /007080 [0038] The membrane separator is a pressure drop device, for example, a high pressure pump 31. 〇 2020/175375 9 boxes (: 171-1?2020/007080
定の圧力に昇圧された対象液を中空糸膜モジュール 1の第 1室 1 1 と第 2室 1 2とに分けて流すことのできる分流弁 4などを備えていてもよい (図 1)It may be equipped with a diversion valve 4 or the like that allows the target liquid pressurized to a constant pressure to flow separately into the first chamber 11 and the second chamber 12 of the hollow fiber membrane module 1 (Fig. 1).
。 なお、 分流弁 4 (圧力低下装置) は、 第 2室 1 2に流される対象液を所定 の圧力より低い圧力に減圧する機能を有している。 .. The flow dividing valve 4 (pressure reducing device) has a function of reducing the pressure of the target liquid flowing in the second chamber 12 to a pressure lower than a predetermined pressure.
[0039] このような圧力低下装置を用いることで、 例えば、 第 1液と第 2液が同じ 液 (対象液) である場合に、 同じ流路から供給される対象液の一部を第 1液 として所定の圧力で第 1室 1 1 に供給しつつ、 対象液の他の一部を第 2液と して、 圧力低下装置を通過させることによって、 所定の圧力より低い圧力で 第 2室 1 2に流すことができ、 該圧力低下装置の上流側の対象液の流路が 1 本で済むという利点がある。 [0039] By using such a pressure reducing device, for example, when the first liquid and the second liquid are the same liquid (target liquid), part of the target liquid supplied from the same channel is While supplying the liquid as a liquid to the first chamber 1 1 at a predetermined pressure, another part of the target liquid is made to be the second liquid and is passed through the pressure reducing device, so that the second chamber is supplied at a pressure lower than the predetermined pressure. It has the advantage that it can be flowed to 12 and only one flow path for the target liquid on the upstream side of the pressure reduction device is required.
[0040] 第 1液および第 2液は、 浸透圧を有する液体である。 当該液体は、 溶質が 溶媒に溶解した溶液であってもよく、 不溶性物質が分散した分散液であって もよい。 溶質としては、 無機または有機の塩類、 酸、 アルカリ、 アルコール 、 糖類、 蛋白質などの可溶性物質が含まれる。 溶媒としては、 これらの溶質 または不溶性物質を溶解または分散させて浸透圧を示す溶液を形成できる物 質が挙げられる。 このような溶媒は、 典型的には水であるが、 アルコールな どの水以外の液体であってもよい。 第 1液および第 2液としては、 例えば、 海水、 河川水、 汽水、 排水、 有機溶剤、 食品、 飲料などが挙げられる。 排水 としては、 例えば、 工業排水、 生活排水、 油田またはガス田の排水 (随伴水 ) などが挙げられる。 [0040] The first liquid and the second liquid are liquids having an osmotic pressure. The liquid may be a solution in which a solute is dissolved in a solvent, or may be a dispersion liquid in which an insoluble substance is dispersed. Solutes include soluble substances such as inorganic or organic salts, acids, alkalis, alcohols, sugars and proteins. Examples of the solvent include substances capable of dissolving or dispersing these solutes or insoluble substances to form a solution having an osmotic pressure. Such a solvent is typically water, but may be a liquid other than water such as alcohol. Examples of the first liquid and the second liquid include seawater, river water, brackish water, wastewater, organic solvents, foods and beverages. Examples of wastewater include industrial wastewater, domestic wastewater, and oilfield or gasfield wastewater (associated water).
[0041 ] また、 本実施形態の膜分離装置が造水システムに用いられる場合、 膜分離 装置に供給される第 1液および第 2液は、 逆浸透工程で排出される濃縮塩水 (ブライン) であってもよい。 [0041] When the membrane separation device of the present embodiment is used in a fresh water production system, the first liquid and the second liquid supplied to the membrane separation device are concentrated brine (brine) discharged in the reverse osmosis process. It may be.
[0042] なお、 膜分離装置は、 図 1 に示されるように 1つの中空糸膜モジュール 1 を用いた 1段の装置であってもよく、 複数の中空糸膜モジュールを用いた多 段の装置であってもよい。 [0042] The membrane separation device may be a one-stage device using one hollow fiber membrane module 1 as shown in Fig. 1, or a multi-stage device using a plurality of hollow fiber membrane modules. May be
[0043] また、 第 1液および第 2液は、 液中に含まれる微粒子、 微生物等を除去す るための前処理が施されたものであってもよい。 前処理としては、 海水淡水 化技術に用いられる種々公知の前処理を実施することができ、 例えば、 ナノ ろ過膜 (N F膜: Nanof i Itration Membrane) 、 限外ろ過膜 (U F膜: Ultra filtration Membrane) 、 精密ろ過膜 (M F膜: Microf i Itration Membrane ) 等を用いたろ過、 次亜塩素酸ナトリウムの添加、 凝集剤添加などが挙げら れる。 [0043] The first liquid and the second liquid may be pretreated to remove fine particles, microorganisms and the like contained in the liquid. As pretreatment, seawater freshwater Various well-known pretreatments used in chemical technology can be carried out. Membrane: Filtration using Microfiitration Membrane), addition of sodium hypochlorite, addition of coagulant, etc.
[0044] 例えば、 図 1 に示される膜分離装置において、 高圧ポンプ 3 1の上流側に は、 図示しない前処理装置を備えていてもよい。 前処理装置は、 ポンプ 30 で取水した原液 (対象液) を砂濾過や U F膜、 MF膜、 力一トリッジフィル 夕一などによって処理する装置である。 前処理装置により、 原液から濁質を 除去し、 中空糸膜モジュール 1等を含む膜分離装置に適合する水質の原液を 得ることができる。 必要により、 p Hの調整手段や塩素添加装置などを付け 加えることも可能である。 For example, in the membrane separation apparatus shown in FIG. 1, a pretreatment device (not shown) may be provided on the upstream side of the high pressure pump 31. The pretreatment device is a device that treats the undiluted solution (target solution) taken by the pump 30 with sand filtration, UF membrane, MF membrane, and force-to-fill film. The pretreatment device can remove turbidity from the stock solution to obtain a water-quality stock solution suitable for a membrane separation device including the hollow fiber membrane module 1 and the like. If necessary, it is possible to add pH adjusting means and chlorine addition equipment.
[0045] <中空糸膜モジュール > [0045] <Hollow fiber membrane module>
以下、 本実施形態に用いられる中空糸膜モジュールの一例について説明す る。 Hereinafter, an example of the hollow fiber membrane module used in this embodiment will be described.
[0046] 図 2および図 3を参照して、 中空糸膜モジュール 1は、 中心に配置された 複数の孔 2 1 を有する芯管 (多孔分配管) 2と、 その周囲に配置された複数 の中空糸膜 1 〇と、 芯管 2および複数の中空糸膜 1 0をそれらの両端で固定 する 2つの樹脂壁 6 1 とを備える。 なお、 複数の中空糸膜 1 0はその両端に 開口部を有している。 これらの部材を含む中空糸膜エレメントは、 2つの保 持部材 62に〇 _リング 62 aが介在した液密状態で保持され、 圧力容器 7 内に収容されている。 [0046] Referring to Figs. 2 and 3, the hollow fiber membrane module 1 includes a core tube (a porous pipe) 2 having a plurality of holes 21 arranged at the center, and a plurality of core tubes arranged around it. A hollow fiber membrane 10 and two resin walls 61 for fixing the core tube 2 and a plurality of hollow fiber membranes 10 at both ends thereof are provided. The plurality of hollow fiber membranes 10 have openings at both ends. The hollow fiber membrane element including these members is held in a pressure vessel 7 in a liquid-tight state in which two holding members 62 are provided with a _ ring 62 a.
[0047] また、 中空糸膜モジュール 1は、 4つのポート (第 1液供給口 1 00 a、 第 1液排出口 1 00 b、 第 2液供給口 1 01 aおよび第 2液排出口 1 01 b ) を有している。 第 1液供給口 1 00 aは、 芯管 2の内部に連通し、 さらに 芯管 2の孔 2 1 を介して中空糸膜 1 0の外側 1 00に連通している。 第 1液 排出口 1 00 bは、 中空糸膜 1 0の外側 1 00に連通している。 第 2液供給 口 1 01 aおよび第 2液排出口 1 01 bは、 中空糸膜 1 0の開口部 (第 1開 〇 2020/175375 1 1 卩(:171? 2020 /007080 [0047] The hollow fiber membrane module 1 has four ports (first liquid supply port 100a, first liquid discharge port 100b, second liquid supply port 101a, and second liquid discharge port 101). b) The first liquid supply port 100 a communicates with the inside of the core tube 2 and further communicates with the outside 100 of the hollow fiber membrane 10 via the hole 21 of the core tube 2. The first liquid outlet 100b communicates with the outside 100 of the hollow fiber membrane 10. The second liquid supply port 101a and the second liquid discharge port 101b are connected to the opening (first opening) of the hollow fiber membrane 10. 〇 2020/175 375 1 1 卩 (:171? 2020 /007080
口部 1 0 3および第 2開口部 1 0 13) を介して複数の中空糸膜 1 0の内部に 連通している。 It communicates with the inside of the plurality of hollow fiber membranes 10 through the mouth portion 103 and the second opening portion 1013).
[0048] 第 1液は、 第 1液供給口 1 0 0 3を介して、 芯管 2内に供給され、 孔 2 1 を介して中空糸膜 1 〇の外側 1 〇〇に流される。 中空糸膜 1 0の外側 1 0 0 を通過した第 1液は、 第 1液排出口 1 〇〇匕から取り出される。 [0048] The first liquid is supplied into the core tube 2 through the first liquid supply port 1003, and is flown to the outer side 100 of the hollow fiber membrane 10 through the hole 21. The first liquid that has passed the outer side 100 of the hollow fiber membrane 10 is taken out from the first liquid discharge port 100.
[0049] 第 2液は、 第 2液供給口 1 0 1 3を介して、 中空糸膜 1 0の第 1開口部 1 [0049] The second liquid is supplied to the first opening 1 of the hollow fiber membrane 10 through the second liquid supply port 1013.
0 3より中空糸膜 1 0の内部 (中空部) に供給される。 中空糸膜 1 0の内部 を流れて通過した第 2液は、 中空糸膜 1 0の第 2開口部 1 0匕を介して、 第 2液排出口 1 0 1 13から取り出される。 It is supplied from the inside of the hollow fiber membrane 10 (hollow part) from the inside. The second liquid flowing through the hollow fiber membrane 10 and passing through the hollow fiber membrane 10 is taken out from the second liquid discharge port 1 0 1 13 via the second opening portion 10 of the hollow fiber membrane 10.
[0050] なお、 本実施形態では、 第 1液を中空糸膜 1 0の外側 1 〇〇に流すと共に 第 2液を中空糸膜 1 0の中空部内に流す場合について説明した。 中空糸膜の 内側 (中空部) を流れる流体 (第 1液) を加圧する場合、 圧力損失が大きく 、 第 1液を十分に加圧することが難しいため、 通常は、 上記のように第 1液 を中空糸膜 1 〇の外側 1 0 0に流すことが好ましい。 [0050] In the present embodiment, the case has been described in which the first liquid is allowed to flow to the outside 100 of the hollow fiber membrane 10 and the second liquid is allowed to flow into the hollow portion of the hollow fiber membrane 10. When pressurizing the fluid (first liquid) flowing inside (hollow part) of the hollow fiber membrane, pressure loss is large and it is difficult to pressurize the first liquid sufficiently. Is preferably flowed to 100 outside the hollow fiber membrane 10.
[0051 ] ただし、 第 1液中に含まれる溶媒が、 中空糸膜 1 〇を透過して第 2液中に 移動すればよいため、 第 1液を中空糸膜 1 〇の外側 1 〇〇に流すと共に第 2 液を中空糸膜 1 〇の中空部内に流してもよく、 反対に、 第 2液を中空糸膜 1 0の外側 1 0 0に流すと共に第 1液を中空糸膜 1 0の中空部内に流してもよ い。 言い換えれば、 中空糸膜モジュール 1 において、 中空糸膜 1 0の内部が 第 1室であり中空糸膜 1 〇の外部が第 2室であってもよく、 反対に、 中空糸 膜 1 0の外部が第 1室であり中空糸膜 1 0の内部が第 2室であってもよい。 [0051] However, since the solvent contained in the first liquid has only to pass through the hollow fiber membrane 10 and move into the second liquid, the first liquid is placed on the outer side 100 of the hollow fiber membrane 10. The second liquid may be allowed to flow into the hollow portion of the hollow fiber membrane 10 while flowing, and conversely, the second liquid may be caused to flow to the outside 100 of the hollow fiber membrane 10 and the first liquid of the hollow fiber membrane 10. It may be poured into the hollow part. In other words, in the hollow fiber membrane module 1, the inside of the hollow fiber membrane 10 may be the first chamber and the outside of the hollow fiber membrane 10 may be the second chamber, and conversely, the outside of the hollow fiber membrane 10 may be outside. May be the first chamber and the inside of the hollow fiber membrane 10 may be the second chamber.
[0052] 芯管 2は、 複数の孔 2 1 を有する管状体であれば特に限定されない。 孔 2 The core tube 2 is not particularly limited as long as it is a tubular body having a plurality of holes 21. Hole 2
1は、 放射状に各方向に設けられていることが好ましい。 また、 芯管 2は、 中空糸膜モジュール 1の略中心部に配置されていることが好ましい。 1 is preferably provided radially in each direction. Further, the core tube 2 is preferably arranged substantially in the center of the hollow fiber membrane module 1.
[0053] 図 3において、
Figure imgf000013_0001
第 1液排出口 1 0 0 第 2液供 給口 1 0 1 3および第 2液排出口 1 0 1 匕は、 壁部材 1 3 , 1 4に設けられ ているが、 このような形態に限定されず適宜変更することができる。 例えば 、 第 1液供給口 1 0 0 3、 第 1液排出口 1 0 0 13、 第 2液供給口 1 0 1 3お 〇 2020/175375 12 卩(:171? 2020 /007080
[0053] In FIG.
Figure imgf000013_0001
The first liquid outlet 1 0 0, the second liquid supply port 1 0 1 3 and the second liquid outlet 1 0 1 are provided on the wall members 1 3 and 1 4, but are not limited to such a form. Instead, it can be changed appropriately. For example, first liquid supply port 1003, first liquid discharge port 10013, second liquid supply port 1013 〇 2020/175 375 12 (:171? 2020/007080
よび第 2液排出口 1 0 1 匕の少なくともいずれかが、 圧力容器 7の外周部に 設けられていてもよい。 At least one of the second liquid discharge port 101 and the second liquid discharge port 101 may be provided on the outer peripheral portion of the pressure vessel 7.
[0054] 中空糸膜モジュールの形態としては、 特に限定されないが、 図 2および図 [0054] The form of the hollow fiber membrane module is not particularly limited.
3に示されるような中空糸膜をストレートに配置したモジュールや、 中空糸 膜を芯管に巻きつけたクロスワインド型モジュールなどが挙げられる。 Examples include a module in which hollow fiber membranes are straightly arranged as shown in 3, and a crosswind type module in which hollow fiber membranes are wound around a core tube.
[0055] <中空糸膜 > [0055] <Hollow fiber membrane>
本実施形態の中空糸膜は、 中空糸型の半透膜である。 The hollow fiber membrane of the present embodiment is a hollow fiber type semipermeable membrane.
[0056] (中空糸膜の内径の収縮率) (Shrinkage of inner diameter of hollow fiber membrane)
本実施形態の中空糸膜は、 後述する所定の膜分離方法に 9 6時間使用され た後の中空糸膜の内径の収縮率 (減少率) が、 使用開始時の内径に対して 0 . 1 %以上 9 %未満である。 In the hollow fiber membrane of this embodiment, the shrinkage rate (reduction rate) of the inner diameter of the hollow fiber membrane after being used for a predetermined membrane separation method described below for 96 hours is 0.1% with respect to the inner diameter at the start of use. % Or more and less than 9%.
[0057] 所定の膜分離方法は、 中空糸膜と、 中空糸膜で仕切られた第 1室および第 [0057] The predetermined membrane separation method is performed by using a hollow fiber membrane, a first chamber and a first chamber that are partitioned by the hollow fiber membrane.
2室と、 を有する中空糸膜モジュールを用いて、 第 1液を第 1圧力で第 1室 に流し、 第 2液を第 1圧力よりも低い第 2圧力で第 2室に流すことで、 第 1 室内の第 1液に含まれる溶媒を中空糸膜を介して第 2室内の第 2液に移行さ せ、 第 1室から濃縮された第 1液である濃縮液を排出し、 第 2室から希釈さ れた第 2液である希釈液を排出する。 By using the hollow fiber membrane module having two chambers, the first liquid is caused to flow into the first chamber at the first pressure, and the second liquid is caused to flow into the second chamber at the second pressure lower than the first pressure, The solvent contained in the first liquid in the first chamber is transferred to the second liquid in the second chamber through the hollow fiber membrane, and the concentrated liquid, which is the concentrated first liquid, is discharged from the first chamber, and the second liquid is discharged. Drain the diluted solution, which is the second diluted solution, from the chamber.
中空糸膜の外側の空間が第 1室であり、 中空糸膜の内側の空間が第 2室で ある。 The space outside the hollow fiber membrane is the first chamber, and the space inside the hollow fiber membrane is the second chamber.
第 1圧力 (外圧) が 5 .
Figure imgf000014_0001
第 2圧力 (内圧) が一定 (中空 糸膜内側の圧力損失が一定) である。
The first pressure (external pressure) is 5.
Figure imgf000014_0001
The second pressure (internal pressure) is constant (the pressure loss inside the hollow fiber membrane is constant).
第 1液と第 2液の浸透圧差は 0 1\/1 3である。 The osmotic pressure difference between the first and second solutions is 0 1\/1 3 .
[0058] 中空糸膜を上記の膜分離方法に継続して使用し、 使用開始から 9 6時間経 過後に、 中空糸膜内側の流入口における流量と流出口における流量とを測定 し、 中空糸膜内側の流入口における流量と流出口における流量との平均値 ( 中空糸膜内平均流量) を算出する。 また、 この 9 6時間経過後の中空糸膜内 平均流量について、 使用開始時の中空糸膜内平均流量からの減少量の使用開 始時の中空糸膜内平均流量に対する比率 (中空糸膜内平均流量の減少率) を 〇 2020/175375 13 卩(:171? 2020 /007080 [0058] The hollow fiber membrane was continuously used in the above-mentioned membrane separation method, and after the lapse of 96 hours from the start of use, the flow rate at the inflow port and the flow rate at the outflow port inside the hollow fiber membrane were measured to obtain the hollow fiber membrane. Calculate the average value (average flow rate in the hollow fiber membrane) of the flow rate at the inlet and the flow rate at the outlet inside the membrane. Regarding the average flow rate in the hollow fiber membrane after the lapse of 96 hours, the ratio of the decrease amount from the average flow rate in the hollow fiber membrane at the start of use to the average flow rate in the hollow fiber membrane at the start of use (in the hollow fiber membrane Average flow reduction rate) 〇 2020/175 375 13 卩(: 171? 2020/007080
求める。 Ask.
[0059] 下記の
Figure imgf000015_0001
より、 流量は中空糸膜の内径の 4乗に比例する ため、 その関係を用いて、 中空糸膜内側の平均流量の減少率から、 中空糸膜 内径の収縮率を算出することができる。 なお、 中空糸膜内側の圧力損失が一 定であるため、 圧力損失は考慮する必要がない。
[0059] Below
Figure imgf000015_0001
Since the flow rate is proportional to the fourth power of the inner diameter of the hollow fiber membrane, the relationship can be used to calculate the shrinkage rate of the inner diameter of the hollow fiber membrane from the reduction rate of the average flow rate inside the hollow fiber membrane. Since the pressure loss inside the hollow fiber membrane is constant, it is not necessary to consider the pressure loss.
[0060] [数 1 ] [0060] [Number 1]
¢1 _ 128 X /X X <3 ¢1 _ 128 X /X X <3
(¾ 6[1-卩01 361^丨丨6式) (¾6[1-卩01 361^丨丨6 formula)
(1 X 兀 <1 I4 (1 X 兀 <1 I 4
[0061 ] 上記式中、 は圧力損失であり、 åは微小区間距離である。 は流体 (第 [0061] In the above formula, is the pressure loss, and is the minute section distance. Is the fluid (No.
2液) の粘性係数であり、 0は中空糸膜内平均流量であり、
Figure imgf000015_0002
は中空糸膜の 内径である。
2 liquid) viscosity coefficient, 0 is the average flow rate in the hollow fiber membrane,
Figure imgf000015_0002
Is the inner diameter of the hollow fiber membrane.
[0062] 中空糸膜の内径は、 好ましくは 4 0 以上 2 0 0 以下であり、 より 好ましくは 7 5 〇!以上 1 8 0 以下である。 [0062] The inner diameter of the hollow fiber membrane is preferably 40 or more and 200 or less, more preferably 750 or more and 180 or less.
[0063] 中空糸膜 (膜全体) の厚みは、 好ましくは 4 0〜 2 0 0 であり、 より 好ましくは 5 0〜 1 7 0 である。 なお、 膜厚は (外径一内径) / 2で算 出できる。 また、 中空糸膜の中空率は、 好ましくは 1 〇〜 5 0 %であり、 よ り好ましくは 1 2〜 4 0 %である。 なお、 中空率は、 中空糸膜の横断面にお ける中空部の面積の割合であり、 「中空部断面積/ (膜部断面積十中空部断 面積) X 1 0 0 (%) 」 で表される。 [0063] The thickness of the hollow fiber membrane (whole membrane) is preferably 40 to 200, and more preferably 50 to 170. The film thickness can be calculated by (outer diameter-inner diameter)/2. The hollowness of the hollow fiber membrane is preferably 10 to 50%, more preferably 12 to 40%. The hollow ratio is the ratio of the area of the hollow part in the cross section of the hollow fiber membrane, and is expressed as "hollow part cross-sectional area / (membrane cross-sectional area + hollow part cross-sectional area) X 100 (%)". expressed.
[0064] 中空糸膜の平均孔径 (膜全体の微細孔の平均孔径) は、 2 n m以下である ことが好ましい。 平均孔径の測定方法としては、 例えば、 示差走査熱量測定 (〇3〇 法が挙げられる。 [0064] The average pore diameter of the hollow fiber membrane (average pore diameter of the membrane entire micropores) is preferably not more than 2 n m. As a method for measuring the average pore diameter, for example, the differential scanning calorimetry (030 method) can be mentioned.
[0065] (ラマン値) [0065] (Raman value)
本発明において、 中空糸膜のラマン値とは、 水で膨潤した状態の前記中空 糸膜の横断面の膜厚方向の複数の点に対して、 ラマン分光法により取得され る複数のラマンスぺクトルの各々における最大ピークのピーク強度において 、 ピーク強度の最大値に対する最小値の比率を意味する。 なお、 ラマン値は 、 中空糸膜の膜厚方向の密度分布の指標となる値であり、 ラマン値が高い程 〇 2020/175375 14 卩(:171? 2020 /007080 In the present invention, the Raman value of a hollow fiber membrane means a plurality of Raman spectra obtained by Raman spectroscopy at a plurality of points in the thickness direction of the cross section of the hollow fiber membrane swollen with water. In the peak intensity of the maximum peak in each of, the ratio of the minimum value to the maximum value of the peak intensity is meant. The Raman value is a value that serves as an index of the density distribution in the thickness direction of the hollow fiber membrane, and the higher the Raman value, the higher the Raman value. 〇 2020/175 375 14 (:171? 2020/007080
、 膜厚方向の密度分布の均一性が高いことを示す。 , Shows that the uniformity of the density distribution in the film thickness direction is high.
[0066] 中空糸膜のラマン値は、 好ましくは 7 2 %以上 9 0 %以下である。 ラマン 値がこの範囲である場合、 中空糸膜が巳(3法による膜分離に用いられたとき に、 中空糸膜の内径の経時的な減少を抑制する効果をより確実に得ることが できる。 The Raman value of the hollow fiber membrane is preferably 72% or more and 90% or less. When the Raman value is within this range, when the hollow fiber membrane is used for membrane separation by the method (3), the effect of suppressing the decrease in the inner diameter of the hollow fiber membrane over time can be more reliably obtained.
[0067] ラマン分光法 (顕微ラマン分光装置) は、 測定試料に対して、 スポッ ト状 に集光したレーザー光を照射することにより発生するラマン散乱光を検出し 、 分光してラマンスペクトルを得る方法 (装置) である (図 7参照) 。 ラマ ンスペクトルは、 試料に対して固有であり、 ある試料に対するラマンスぺク トルにおける最大ピーク (試料の主構成材料に固有のピーク) の強度は、 試 料の構成材料の密度に相関する。 したがって、 このようなピーク強度を測定 することで、 試料中の構成材料の密度の分布状態を解析することが可能であ る。 [0067] Raman spectroscopy (microscopic Raman spectroscope) detects Raman scattered light generated by irradiating a measurement sample with laser light focused in a spot shape, and obtains a Raman spectrum by spectral analysis. Method (apparatus) (see Figure 7). The Raman spectrum is unique to a sample, and the intensity of the maximum peak in the Raman spectrum (peak unique to the main constituent material of the sample) for a certain sample is correlated with the density of the constituent material of the sample. Therefore, by measuring such peak intensity, it is possible to analyze the distribution state of the density of the constituent materials in the sample.
[0068] なお、 試料の構成材料の密度分布状態を精度よく測定するため、 レーザー ラマン顕微鏡の対物レンズとして、 空間分解能が 2 以下であるような対 物レンズを用いる。 測定時におけるレーザーラマン顕微鏡のレーザー光源の 強度は、 測定中に試料の劣化が起きない程度に弱く、 数秒〜数十分の露光時 間でラマンスペクトルが得られる範囲で任意に設定することができる。 [0068] In order to accurately measure the density distribution state of the constituent material of the sample, an objective lens having a spatial resolution of 2 or less is used as the objective lens of the laser Raman microscope. The intensity of the laser light source of the laser Raman microscope at the time of measurement is weak enough not to cause deterioration of the sample during measurement, and it can be arbitrarily set within the range where a Raman spectrum can be obtained from several seconds to several tens of minutes of exposure time. ..
[0069] 具体的には、 まず、 中空糸膜を氷包埋し、 ミクロトームで断面を作製する 。 作製した断面試料を水に浸潰し (水に膨潤させた状態にし) 、 断面が水面 からわずかに出た状態にする (図 7参照) 。 その断面について、 顕微ラマン 分光装置 (レーザーラマン顕微鏡) を用いて、 マッピング (スポッ ト状に集 光したレーザー光を走査することで、 設定した範囲のラマンスぺクトルを測 定する手法) 又はイメージング測定 (ライン状に集光したレーザー光を走査 することで、 設定した範囲のラマンスペクトルを測定する手法) により (参 考文献: 日本分光学会 (2009、 第 1刷) 『顕微分光法 ナノ ·マイクロの世界 を見る分光法』 (分光測定入門シリーズ第 10巻) 講談社サイエンティフィク ) 、 ラマンスペクトル (ラマンスペクトルにおける最大ピークのピーク強度 〇 2020/175375 15 卩(:171? 2020 /007080 [0069] Specifically, first, a hollow fiber membrane is embedded in ice, and a cross section is prepared with a microtome. Immerse the prepared cross-section sample in water (so that it swells in water), and make the cross-section slightly protrude from the water surface (see Fig. 7). Using a Raman microscope (laser Raman microscope) for the cross section, mapping (a method of measuring the Raman spectrum within a set range by scanning the laser light collected in spots) or imaging measurement (A method of measuring the Raman spectrum in a set range by scanning a laser beam focused in a line) (Reference: The Spectroscopical Society of Japan (2009, 1st edition) Spectroscopy for Seeing the World” (Introduction to Spectroscopy Series Volume 10) Kodansha Scientific), Raman spectrum (peak intensity of the maximum peak in Raman spectrum) 〇 2020/175 375 15 卩 (: 171-1? 2020 /007080
) を測定する。 測定は、 中空糸膜の断面における膜厚方向の複数の箇所につ いて実施される。 ) Is measured. The measurement is carried out at a plurality of locations in the thickness direction on the cross section of the hollow fiber membrane.
[0070] ラマン値の算出のために測定されるラマンスぺクトルの各々における最大 ピークは、 例えば、 波長 2 9 3 5〇 - 1付近の C H (炭素一水素結合) の伸 縮振動に相当するピークなど、 最も強度の高いピークである (図 9参照) 。 ピーク強度は、 選択したピークのピーク面積またはピーク高さから算出する ことができる。 [0070] Maximum peak in each of Ramansu Bae vector measured for the calculation of the Raman value is, for example, wavelength 2 9 3 5_Rei - peaks corresponding to the extensor contraction vibration of 1 near CH (carbon monohydrogen bond) Is the highest peak (see Fig. 9). The peak intensity can be calculated from the peak area or peak height of the selected peak.
[0071 ] 実際の測定では、 まず、 中空糸膜の断面を顕微鏡で観察しながら、 中空糸 膜の膜部分 (図 8の実線の部分) を含む膜厚方向の所定範囲 (図 8の破線矢 印の部分) について、 1 の間隔で、 内側から外側 (図 8の左側から右側 ) に向かって、 あるいは外側から内側 (図 8の右側から左側) に向かって、 複数のラマンスぺクトルの各々における最大ピーク (波長 2 9 3 5〇
Figure imgf000017_0001
付 近のピーク) のピーク強度が測定される。 その後で、 測定された複数のピー ク強度のデータから、 中空糸の膜部分 (図 8の実線矢印の部分) に関するデ —夕のみが取り出される。
In the actual measurement, first, while observing the cross section of the hollow fiber membrane with a microscope, a predetermined range in the film thickness direction including the membrane portion of the hollow fiber membrane (the solid line portion in FIG. 8) (broken line arrow in FIG. 8) (Marked portion) at intervals of 1 from the inside to the outside (left to right in FIG. 8) or from the outside to the inside (right to left in FIG. 8) of each of the multiple Raman spectra. Maximum peak (wavelength 2 9 3 5 0
Figure imgf000017_0001
The peak intensity of the (nearest peak) is measured. After that, only the data related to the hollow fiber membrane part (the part indicated by the solid arrow in Fig. 8) is extracted from the measured peak intensity data.
[0072] 例えば、 まず、 測定された全てのピーク強度のうちの最大値を 1 0 0とし て、 他のピーク強度の比率 (ピーク強度比) が算出される。 図 1 0に、 ピー ク強度比のグラフの一例を示す。 図 1 0において、 X軸は膜断面における膜 厚方向 (図 8の矢印の方向) の位置を示し、 丫軸はピーク強度比を示す。 な お、 図 1 0に示されるピーク強度比は、 中空糸膜を構成するポリマー (〇丁 八) に由来する
Figure imgf000017_0002
付近のピーク (図 9参照) の強度比であり、 そのピーク強度比はポリマー密度と相関する。
[0072] For example, first, assuming that the maximum value of all measured peak intensities is 100, the ratio of other peak intensities (peak intensity ratio) is calculated. Figure 10 shows an example of a peak intensity ratio graph. In Fig. 10, the X axis indicates the position in the film thickness direction (direction of the arrow in Fig. 8) in the film cross section, and the vertical axis indicates the peak intensity ratio. The peak intensity ratio shown in Fig. 10 is derived from the polymer (○○○) that constitutes the hollow fiber membrane.
Figure imgf000017_0002
It is the intensity ratio of the nearby peaks (see Fig. 9), and the peak intensity ratio correlates with the polymer density.
[0073] ここで、 図 1 0において、 ピーク強度比の最大値 (1 0 0 %) を含み、 1 間隔で測定された隣の点同士の値 (ピーク強度比) の変化率が 5 % (絶 対値) 以内の部分が膜部分 (図 8の実線矢印で示される部分) であり、 5 % を超える点から外側 (図 1 〇で点ハッチングされた部分) は膜以外の部分で あると判断して、 膜以外の部分のデータは削除される。 [0073] Here, in Fig. 10, the rate of change in the value between adjacent points (peak intensity ratio) measured at one interval including the maximum value of the peak intensity ratio (100%) was 5% ( The part within (absolute value) is the film part (the part indicated by the solid arrow in Fig. 8), and the part outside 5% is the part other than the film (the part hatched in Fig. 10). Judgment is made and the data other than the membrane is deleted.
[0074] このようにして得られた膜部分のピーク強度 (ピーク強度比) のうちの最 〇 2020/175375 16 卩(:171? 2020 /007080 [0074] Of the peak intensities (peak intensity ratios) of the film portion thus obtained, the maximum 〇 2020/175 375 16 卩 (: 171-1? 2020 /007080
小値を決定し、 ピーク強度の最大値に対する最小値の比率 (最小値のピーク 強度比:図 1 〇参照) がラマン値として求められる。 A small value is determined, and the ratio of the minimum value to the maximum value of the peak intensity (the peak intensity ratio of the minimum value: see Fig. 10) is obtained as the Raman value.
[0075] (断面内形) [0075] (Internal shape)
中空糸膜の断面内形は、 好ましくは三角形状である。 この場合、 長期使用 における中空糸膜の潰れが抑制され、 中空糸膜の強度が高くなるという利点 がある。 三角形状とは、 三角形に近い形状であることを意味し、 おにぎり形 (おむすび形) やルーローの三角形のような辺が直線でないものや角のない 形も含む概念である (特許文献 6 :国際公開第 2 0 1 7 / 1 2 2 6 7 3号参 照) 。 The inner shape of the hollow fiber membrane in cross section is preferably triangular. In this case, there is an advantage that the hollow fiber membrane is prevented from being crushed during long-term use and the strength of the hollow fiber membrane is increased. The triangular shape means a shape close to a triangle, and is a concept including a shape such as a rice ball shape (rice ball shape) and a Reuleaux triangle in which the sides are not straight and there is no corner (Patent Document 6: International See Publication No. 201/1/2 2 6 7 3).
[0076] なお、 三角形の辺付近の膜厚 (最厚膜厚) に対する三角形の頂点付近の膜 厚 (最薄膜厚) の比率 (最薄膜厚/最厚膜厚) は、 好ましくは〇. 6 5〜〇 . 9 0である。 当該比率が〇. 6 5未満の場合は、 最薄膜厚が薄すぎて変形 しやすく (潰れ易く) なる可能性がある。 一方、 当該比率が〇. 9 0より大 きい場合は、 膜断面の内形が円形に近づくため長期使用における潰れを抑制 する効果が得られ難くなる。 [0076] Note that the ratio of the film thickness near the apex of the triangle (the thinnest film thickness) to the film thickness near the sides of the triangle (the thinnest film thickness) (the thinnest film thickness/the thickest film thickness) is preferably 0.6. It is 5 to 0.90. If the ratio is less than 0.65, the thinnest film may be too thin and may be easily deformed (crushed). On the other hand, when the ratio is larger than 0.90, the inner shape of the cross section of the film approaches a circle, so that it is difficult to obtain the effect of suppressing crushing in long-term use.
[0077] 最薄膜厚/最厚膜厚 (最厚膜厚に対する最薄膜厚の比率) の算出方法につ いて、 中空糸膜の断面を表わす図 1 1 を用いて説明する。 図 1 1の中空糸膜 の断面において三角形状の三つの頂点をそれぞれ 3、 13、 〇とし、 3点を直 線で結んだ三角形の三つの辺を 3 13、 13 0、 〇 3とする。 点 3から辺 13〇に 向かって垂線 3
Figure imgf000018_0001
を引き、 垂線 3
Figure imgf000018_0002
の延長上での中空糸膜断面外周との交点 を 9、 および」 とする。 点 13および点〇からもそれぞれ辺〇 3、 辺 13 0に垂 線を引き、 図 1 1 に示されるように点㊀、 点 [1、 点 1<、 点 1"、 点丨、 点丨 を 定める。 なお、 図 1 1 において、 中空糸膜の断面外形は略円形であり、 中空 部は (三角) おむすび形である。 図 1 1 に示すように最薄膜厚 3 」、 匕 1<、
A method for calculating the thinnest film thickness/thickest film thickness (ratio of the thinnest film thickness to the thickest film thickness) will be described with reference to FIG. 11 showing a cross section of the hollow fiber membrane. In the cross section of the hollow fiber membrane in Fig. 11, three triangular vertices are designated as 3, 13, and ◯, respectively, and three sides of the triangle connecting the three points with straight lines are designated as 313, 130, and 〇 3, respectively. Perpendicular 3 from point 3 to side 130
Figure imgf000018_0001
Draw a vertical line 3
Figure imgf000018_0002
The intersection point with the outer circumference of the cross section of the hollow fiber membrane on the extension of is 9 and. From points 13 and 〇, draw lines perpendicular to sides 0 3 and 130, respectively, and draw points ㊀, point [1, point 1<, point 1", point 丨, point 丨 as shown in Fig. 11. In Fig. 11, the hollow fiber membrane has a roughly circular cross-sectional outer shape, and the hollow part has a (triangular) rice ball shape.As shown in Fig. 11, the thinnest film thickness is 3", and the sill 1<,
〇 丨 と、 それぞれに向かい合う最厚膜厚 ¢1 9、 e h . f i とについて、 中空 糸膜の断面写真によって測定し、 その測定値から最薄膜厚/最厚膜厚の比 ( 3つの値の各々、 またはそれらの平均値) を算出することができる。 〇 丨 and the thickest film thickness ¢19, eh .fi facing each other were measured by the cross-sectional photograph of the hollow fiber membrane, and the ratio of the thinnest film thickness/the thickest film thickness (of the three values Each, or their average value) can be calculated.
[0078] (材料) 〇 2020/175375 17 卩(:171? 2020 /007080 [0078] (Material) 〇 2020/175 375 17 卩 (: 171-1? 2020 /007080
中空糸膜を構成する材料としては、 特に限定されないが、 セルロース系樹 月旨、 ポリスルホン系樹脂およびポリアミ ド系樹脂の少なくともいずれかを含 む材料であることが好ましく、 セルロース系樹脂およびポリスルホン系樹脂 の少なくともいずれかを含む材料であることがより好ましい。 The material constituting the hollow fiber membrane is not particularly limited, but a material containing at least one of cellulose-based resin, polysulfone-based resin and polyamide-based resin is preferable, and cellulose-based resin and polysulfone-based resin are preferable. It is more preferable that the material includes at least one of the above.
[0079] セルロース系樹脂は、 好ましくは酢酸セルロース系樹脂である。 酢酸セル 口ース系樹脂は、 殺菌剤である塩素に対する耐性があり、 微生物の増殖を抑 制できる特徴を有している。 酢酸セルロース系樹脂は、 好ましくは酢酸セル 口ースであり、 耐久性の点から、 より好ましくは三酢酸セルロースである。 [0079] The cellulose-based resin is preferably a cellulose acetate-based resin. Cellulose acetate Cell-based resins are resistant to chlorine, which is a bactericide, and have the characteristic of suppressing the growth of microorganisms. The cellulose acetate-based resin is preferably acetate acetate, and more preferably cellulose triacetate from the viewpoint of durability.
[0080] ポリスルホン系樹脂は、 好ましくはポリエーテルスルホン系樹脂である。 [0080] The polysulfone-based resin is preferably a polyethersulfone-based resin.
ポリエーテルスルホン系樹脂は、 好ましくはスルホン化ポリエーテルスルホ ンである。 The polyether sulfone resin is preferably a sulfonated polyether sulfone.
[0081 ] 中空糸膜としては、 単層構造の膜が挙げられる。 ここで、 中空糸膜の膜厚 方向の構造均質性が高いことが好ましい。 中空糸膜の膜厚方向の構造均質性 の指標としては、 例えば、 上述した中空糸膜のラマン値が所定値以上の範囲 にあることや、 倍率 5 0 0 0倍の走査型電子顕微鏡 (3巳 IV!) を用いて中空 糸膜の横断面を膜厚方向に向かって連続的に観察した際に構造の変化が少な いことが挙げられる。 [0081] Examples of the hollow fiber membrane include a membrane having a single layer structure. Here, it is preferable that the hollow fiber membrane has high structural homogeneity in the thickness direction. As an index of the structural homogeneity in the thickness direction of the hollow fiber membrane, for example, the Raman value of the above-mentioned hollow fiber membrane is in a range of a predetermined value or more, or a scanning electron microscope with a magnification of 500 times (3 There is little change in the structure when the cross-section of the hollow fiber membrane is continuously observed in the direction of the membrane thickness using Mami IV!).
[0082] <中空糸膜の製造方法 > <Method for producing hollow fiber membrane>
本発明は、 上記の中空糸膜を得るための中空糸膜の製造方法にも関する。 The present invention also relates to a method for producing a hollow fiber membrane for obtaining the above hollow fiber membrane.
[0083] 図 6を参照して、 本実施形態の中空糸膜の製造方法は、 少なくとも紡糸エ 程と後処理工程とを含む。 With reference to FIG. 6, the method for manufacturing a hollow fiber membrane of the present embodiment includes at least a spinning step and a post-treatment step.
[0084] 〔紡糸工程〕 [Spinning Step]
紡糸工程では、 原料溶液 8 0をノズル 8 1から空中走行部を経て凝固液 9 1中に吐出して、 原料溶液の凝固物を凝固液中から曳き出すことにより、 中 空糸型の半透膜である中空糸膜が得られる。 中空糸膜の曳き出し等は、 例え ば、 口ーラー 8 2 , 8 3 , 8 4 , 8 5により行われる。 なお、 曳き出し速度 は、 口ーラー 8 3の表面速度である。 In the spinning process, the raw material solution 80 is discharged from the nozzle 8 1 into the coagulating liquid 91 via the aerial traveling section, and the coagulated product of the raw material solution is pulled out from the coagulating liquid, so that the hollow fiber type semi-permeable type A hollow fiber membrane that is a membrane is obtained. For example, pulling out of the hollow fiber membrane is performed by mouth rollers 8 2, 8 3, 8 4 and 8 5. The pulling speed is the surface speed of the mouth roller 83.
[0085] 原料溶液は、 中空糸膜の原材料 (上述の中空糸膜を構成する材料) と、 溶 〇 2020/175375 18 卩(:171? 2020 /007080 [0085] The raw material solution is prepared by dissolving the raw material of the hollow fiber membrane (the material forming the hollow fiber membrane described above) 〇 2020/175 375 18 卩 (: 171-1? 2020 /007080
媒および非溶媒と、 を含む。 原料溶液中の溶媒/非溶媒の質量比は、 好まし くは 5 0 / 5 0〜 7 0 / 3 0である。 なお、 溶媒は、 原材料を溶解可能な液 体であり、 非溶媒は、 原材料が溶解しない液体である。 And a medium and a non-solvent. The solvent/non-solvent mass ratio in the raw material solution is preferably 50/50 to 70/30. The solvent is a liquid that can dissolve the raw materials, and the non-solvent is a liquid that does not dissolve the raw materials.
[0086] 凝固液の濃度 〔 (3 +水以外の N 3) /凝固液の質量比率〕 は、 好ましく は 1 0 %〜 6 0 %であり、 より好ましくは 2 0 %〜 5 0 %である。 また、 凝 固液の温度は、 好ましくは 1 〇〜 3 0 °〇であり、 より好ましくは 1 〇〜 2 5 °0である。 [0086] The concentration of the coagulating liquid [(N3 other than 3 + water)/mass ratio of the coagulating liquid] is preferably 10% to 60%, more preferably 20% to 50%. .. Further, the temperature of the solidified liquid is preferably 10 to 30 ° , and more preferably 10 to 25°0.
[0087] 紡糸工程において、 延伸倍率 (ドラフト比) は、 2 . 1〜 5 . 0であり、 好ましくは 2 . 2〜 4 . 0である。 なお、 延伸倍率は、 ノズルの出口におけ る原料溶液の吐出速度 (ノズルから吐出される原料溶液の線速度) (V。) に 対する曳き出し速度 (曳き出される原料溶液の凝固物の線速度) (V の比 率 ハ〇) である。 なお、 特許文献 2〜 6には、 紡糸工程における延伸 倍率は記載されていない。 [0087] In the spinning step, the draw ratio (draft ratio) is 2.1 to 5.0, and preferably 2.2 to 4.0. The draw ratio is the drawing speed (the linear speed of the raw material solution discharged from the nozzle) (V.) at the discharge rate of the raw material solution at the outlet of the nozzle (the linear speed of the coagulated raw material solution). ) (V ratio c). It should be noted that Patent Documents 2 to 6 do not describe the draw ratio in the spinning step.
[0088] 〔後処理工程〕 [Post-Processing Step]
後処理工程では、 紡糸工程で得られた中空糸膜 8 6が水洗された後に、 熱 水処理および塩漬処理に供される。 In the post-treatment step, the hollow fiber membrane 86 obtained in the spinning step is washed with water and then subjected to hot water treatment and salting treatment.
[0089] (熱水処理) [0089] (Hot water treatment)
熱水処理では、 中空糸膜 8 6が熱水 9 2に浸潰される。 熱水処理における 熱水 9 2の温度 (熱水処理の温度) は、 好ましくは 8 6 °〇以上 1 0 0 °〇未満 であり、 より好ましくは 9 0〜 9 9 . 5 °〇であり、 さらに好ましくは 9 5〜 In the hot water treatment, the hollow fiber membrane 86 is immersed in hot water 92. The temperature of the hot water 92 in the hot water treatment (temperature of the hot water treatment) is preferably not less than 86 ° 〇 and less than 100 ° 〇, more preferably 90 to 99.5 ° 〇, More preferably 95-
9 9 °〇である。 このように、 従来よりも高い温度での熱水処理を行うことに より、 中空糸膜の緻密化が進みやすくなるため、 中空糸膜の内径の経時的な 減少を抑制することができる。 なお、 熱水処理は、 無緊張状態の中空糸膜 8 6に対して行われることが好ましい。 It is 9 9 ° 〇. As described above, by performing the hot water treatment at a temperature higher than in the past, the densification of the hollow fiber membrane is facilitated, so that the decrease in the inner diameter of the hollow fiber membrane with time can be suppressed. The hot water treatment is preferably performed on the hollow fiber membranes 86 in a tension-free state.
[0090] 熱水処理の時間は、 好ましくは 5〜 1 2 0分間であり、 より好ましくは 1 〇〜 4 0分間である。 [0090] The hot water treatment time is preferably 5 to 120 minutes, and more preferably 10 to 40 minutes.
[0091 ] (塩漬処理) [0091] (Salted treatment)
塩漬処理では、 熱水処理後の中空糸膜 8 6が塩水 9 3に浸潰される。 塩水 〇 2020/175375 19 卩(:171? 2020 /007080 In the salting treatment, the hollow fiber membrane 86 after hot water treatment is immersed in salt water 93. brine 〇 2020/175 375 19 卩 (:171? 2020 /007080
9 3は、 塩化物イオンを含む水溶液である。 塩水 9 3としては、 例えば、 塩 化ナトリウム (食塩) 、 塩化カリウム、 塩化マグネシウム、 塩化カルシウム 、 塩化リチウム等の水溶液が挙げられる。 塩水 9 3の濃度は、 好ましくは 0 . 5〜 2 0質量%であり、 より好ましくは 1 . 〇〜 1 0質量%である。 塩水 9 3の温度 (塩漬処理の温度) は、 好ましくは 7 0 °〇以上 9 5 °〇以下であり 、 より好ましくは 7 5 °〇以上 9 0 °〇以下である。 93 is an aqueous solution containing chloride ions. Examples of the salt water 93 include aqueous solutions of sodium chloride (salt), potassium chloride, magnesium chloride, calcium chloride, lithium chloride and the like. The concentration of the salt water 93 is preferably 0.5 to 20% by mass, and more preferably 1.0 to 10% by mass. The temperature of the salt water 93 (the temperature of the salting treatment) is preferably 70°° or more and 95°° or less, more preferably 75°° or more and 90°° or less.
[0092] 塩漬処理の時間は、 好ましくは 1〜 6 0分間であり、 より好ましくは 5〜 [0092] The time for the salting treatment is preferably 1 to 60 minutes, more preferably 5 to
3 0分間である。 なお、 塩漬処理は、 無緊張状態の中空糸膜 8 6に対して行 われることが好ましい。 30 minutes. The salting treatment is preferably performed on the hollow fiber membranes 86 in a tension-free state.
[0093] 中空糸膜の I 口収縮率を抑える効果は、 中空糸膜の膜厚方向の構造均質性 を高めることにより達成されると考えられる。 その主要な具体的手段として 、 原料溶液の
Figure imgf000021_0001
比 (溶媒/非溶媒比) 、 ドラフト比、 塩漬処理 (およ び熱水処理) の条件の変更が挙げられる。 従来よりも原料溶液の 3 / 3比 を小さくする (N 3の割合を高める) ことにより脱溶媒速度が遅くなり、 析 出したポリマーの核成長が均一になることで膜のポリマー密度が膜厚方向で 均質化すると考えられる。 また、 ドラフト比を従来よりも大きくすることに より膜を構成するポリマー分子の一部が配向し、 膜の強度が高まると考えら れる。 また、 熱水処理に続く塩漬処理によって、 膜中より脱水されることで 細孔が収縮し、 ポリマー密度の均質化と高強度化が進むと考えられる。
It is considered that the effect of suppressing the I-portion shrinkage of the hollow fiber membrane is achieved by increasing the structural homogeneity of the hollow fiber membrane in the thickness direction. As the main concrete means,
Figure imgf000021_0001
The ratio (solvent/non-solvent ratio), draft ratio, and salting treatment (and hot water treatment) conditions may be changed. By lowering the 3/3 ratio of the raw material solution (increasing the ratio of N 3) than before, the desolvation rate becomes slower, and the nucleus growth of the precipitated polymer becomes more uniform, so the polymer density of the film becomes It is considered to homogenize in the direction. In addition, it is considered that by increasing the draft ratio compared with the conventional method, some of the polymer molecules constituting the film are oriented and the strength of the film is increased. In addition, it is considered that the pores shrink due to dehydration from the film by the salting treatment following the hot water treatment, and the homogenization of polymer density and the enhancement of strength are promoted.
[0094] <膜分離方法 > [0094] <Membrane separation method>
本発明は、 上記の中空糸膜モジュール 1 を用いる膜分離方法にも関する。 本実施形態の膜分離方法により、 第 1液から濃縮液 (濃縮された第 1液) が 得られると共に、 第 2液から希釈液 (希釈された第 2液) が得られる。 The present invention also relates to a membrane separation method using the above hollow fiber membrane module 1. According to the membrane separation method of the present embodiment, a concentrated liquid (concentrated first liquid) is obtained from the first liquid, and a diluting liquid (diluted second liquid) is obtained from the second liquid.
[0095] 本実施形態の膜分離方法では、 中空糸膜モジュール 1 に対して、 第 1液を 所定の圧力で第 1室 1 1 に流し、 第 2液を所定の圧力よりも低い圧力で第 2 室 1 2に流すことで、 第 1室 1 1内の第 1液に含まれる溶媒を中空糸膜を介 して第 2室 1 2内の第 2液に移行させ、 第 1室 1 1から濃縮液を排出し、 第 2室 1 2から希釈液を排出する。 ここで、 第 1液と第 2液の浸透圧差は 4 !\/1 〇 2020/175375 20 卩(:171? 2020 /007080 [0095] In the membrane separation method of the present embodiment, the first liquid is caused to flow into the first chamber 11 at a predetermined pressure and the second liquid is supplied to the hollow fiber membrane module 1 at a pressure lower than the predetermined pressure. By flowing into the second chamber 1 2, the solvent contained in the first liquid in the first chamber 11 is transferred to the second liquid in the second chamber 12 via the hollow fiber membrane, and the first chamber 1 1 Drain the concentrated liquid from and the diluted liquid from the second chamber 1 2. Here, the osmotic pressure difference between the first and second liquids is 4 !\/1 〇 2020/175 375 20 (:171? 2020/007080
9 3以下である。 9 3 or less.
[0096] 尚、 本実施形態の膜分離方法において、 第 1室 1 1は中空糸膜の外側であ り、 第 2室 1 2は中空糸膜の内側であることが好ましいが、 第 1室 1 1が中 空糸膜の内側であり、 第 2室 1 2が中空糸膜の外側であってもよい。 [0096] In the membrane separation method of the present embodiment, it is preferable that the first chamber 11 is outside the hollow fiber membrane and the second chamber 12 is inside the hollow fiber membrane. 11 may be inside the hollow fiber membrane and the second chamber 12 may be outside the hollow fiber membrane.
[0097] また、 本発明は、 上記膜分離方法に用いられる上述の中空糸膜にも関する [0097] The present invention also relates to the above hollow fiber membrane used in the above membrane separation method.
実施例 Example
[0098] 以下、 実施例を挙げて本発明をより詳細に説明するが、 本発明はこれらに 限定されるものではない。 Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.
[0099] 〔実施例 1〕 [Example 1]
実施形態で説明した中空糸膜の製造方法により、 以下の条件で実施例 1の 中空糸膜が製造された。 The hollow fiber membrane of Example 1 was produced under the following conditions by the method for producing a hollow fiber membrane described in the embodiment.
[0100] [原料溶液の組成] [0100] [Composition of raw material solution]
ポリマー:三酢酸セルロース (〇 7 A) (6 %粘度: 9 5 01 3 3、 ダ イセル社製) ただし、 比較例 3のみ低粘度の <3丁八 ( 6 %粘度: 5 6 8 3、 ダイセル社製) Polymer: Cellulose triacetate (○ 7 A) (6% viscosity: 9 5 01 3 3, manufactured by Daicel) However, only Comparative Example 3 has a low viscosity <3-8 (6% viscosity: 5 6 8 3, Daicel) (Made by the company)
ポリマー含有量:表 1 に示すとおり Polymer content: As shown in Table 1
溶媒: 1\1—メチルピロリ ドン ( IV! ) Solvent: 1\1—Methylpyrrolidone (IV!)
非溶媒:エチレングリコール (巳〇) Non-solvent: ethylene glycol (Mix 〇)
(溶媒/非溶媒
Figure imgf000022_0001
に示すとおり)
(Solvent/non-solvent
Figure imgf000022_0001
(As shown in)
安息香酸:表 1 に示すとおり Benzoic acid: As shown in Table 1.
[0101 ] なお、 上記の〇丁八の 6 %粘度は以下のようにして測定された値である。 [0101] Note that the above 6% 6% viscosity is a value measured as follows.
混合溶剤 [塩化メチレン: メタノール = 9 1 : 9 (重量比) ] 6 1 . 6 7 9を三角フラスコに採取し、 1 0 5 ± 5 °〇で 2時間乾燥した試料 3 . 0 0 9 を投入し、 密栓した。 その後、 横振り振盪機で約 1 . 5時間振盪し、 さらに 回転振盪機で約 1時間振盪して、 完全に溶解させた。 次に、 得られた 6 1 / V〇 I %溶液の温度を恒温槽で 2 5 ± 1 °〇に調整し、 オストワルト粘度計 を用いて計時用標線間の流下時間を測定し、 下記式から粘度を求めた。 〇 2020/175375 21 卩(:171? 2020 /007080 Mix the mixed solvent [methylene chloride:methanol = 91:9 (weight ratio)] 6 1.6 7 9 into an Erlenmeyer flask and add sample 3.0 9 dried at 105 ± 5 ° 〇 for 2 hours. And sealed. Then, it was shaken with a horizontal shaker for about 1.5 hours and further with a rotary shaker for about 1 hour to completely dissolve it. Next, the temperature of the obtained 61/V○I% solution was adjusted to 25±1°○ in a constant temperature bath, and the downflow time between the time-measured marked lines was measured using an Ostwald viscometer. The viscosity was calculated from 〇 2020/175 375 21 卩 (: 171-1? 2020 /007080
6%粘度 (0! 3 3) =流下時間 (360) /粘度計係数 6% viscosity (0! 3 3) = downflow time (360) / viscometer coefficient
なお、 粘度計係数は、 粘度計校正用標準液を用いて、 上記と同様の操作で 流下時間 (360) を測定し、 下記式から求めた。 The viscometer coefficient was calculated from the following formula by measuring the flow-down time (360) in the same operation as above using a standard solution for viscometer calibration.
粘度計係数 = [標準液絶対粘度 (01 ? 3 3) X溶液の密度 ( 1. 235 9/〇 ^3) ] / [標準液の密度 (9/〇 013) X標準液の流下時間 (360 ) ] Viscometer coefficient = [Absolute viscosity of standard solution (01 ?3 3) X density of solution (1.235 9/〇^ 3 )] / [Density of standard solution (9/〇 01 3 ) X Flow time of standard solution ( 360)]]
[0102] [紡糸工程の条件] [0102] [Conditions of spinning process]
原料溶液の溶解温度: 1 85 °0 Melting temperature of raw material solution: 1 85 ° 0
原料溶液の吐出温度: 1 5 1 °Discharge temperature of raw material solution: 1 5 1 °
吐出用のノズル: 3分割ノズル (ノズルの断面積: 0. 05〇1〇12Nozzle for discharge: 3-split nozzle (Nozzle cross-sectional area: 0.05 1 0 1 2 )
〔ノズルの断面積とは、 ノズルの先端部分における原料溶液吐出孔の断 面積である。 〕 [The cross-sectional area of the nozzle is the cross-sectional area of the raw material solution discharge hole at the tip of the nozzle. ]
空中走行部 ( 〇) 滞留時間: 〇. 05秒 Aerial running part (〇) Residence time: 〇.05 seconds
〔 八〇滞留時間 = 〇長/ { (吐出線速度十曳き出し速度) /2} [80 dwell time = 〇 long / {(discharge linear velocity 10 drawing speed) / 2}
]
紡糸工程の延伸倍率:表 1 に示すとおり Stretching ratio of spinning process: As shown in Table 1.
凝固液の組成 Composition of coagulation liquid
溶媒 ( 3) : IV! Solvent (3): IV!
水以外の非溶媒 (N3) : 巳〇 Non-solvents other than water (N3): M
water
凝固液の濃度 〔3 +水以外の 3) /凝固液の質量比率〕 :表 1 に示す とおり。 Concentration of coagulation liquid [3 + 3 other than water / mass ratio of coagulation liquid]: As shown in Table 1.
凝固液中の溶媒/水以外の非溶媒 (3/水以外の N3) の質量比:表 1 に示す原料溶液の 3 / 3と同じ。 Mass ratio of solvent/non-solvent other than water (3/N3 other than water) in coagulation liquid: Same as 3/3 of raw material solution shown in Table 1.
凝固液の温度:表 1 に示すとおり Coagulating liquid temperature: As shown in Table 1
曳き出し速度: 40〇!/分 Pulling speed: 40 〇!/min
[0103] なお、 吐出用のノズルとして 3分割ノズルを用いることにより、 中空糸膜 の断面内形が図 1 1 に示されるようなおにぎり形である中空糸膜が得られた 〇 2020/175375 22 卩(:171? 2020 /007080 [0103] By using a three-division nozzle as the discharge nozzle, a hollow fiber membrane whose inner cross-sectional shape was a rice ball shape as shown in Fig. 11 was obtained. 〇 2020/175 375 22 卩 (: 171-1? 2020 /007080
[0104] [後処理工程の条件] [0104] [Conditions of post-treatment process]
熱水処理の条件:表 1 に示すとおり Conditions for hot water treatment: As shown in Table 1.
塩漬 (塩アニール) 処理の条件:表 1 に示すとおり Conditions for salting (salt annealing): As shown in Table 1.
[0105] 〔実施例 2〕 [Example 2]
表 1 に示されるように、
Figure imgf000024_0001
3比が変更された。 それ以外は実施例 1 と 同様にして、 実施例 2の中空糸膜が製造された。
As shown in Table 1,
Figure imgf000024_0001
3 Ratio changed. Otherwise in the same manner as in Example 1, the hollow fiber membrane of Example 2 was produced.
[0106] 〔実施例 3〜 6〕 [Examples 3 to 6]
表 1 に示されるように、 塩漬処理の条件 (食塩水濃度、 温度) が変更され た。 それ以外は実施例 2と同様にして、 実施例 3〜 6の中空糸膜が製造され た。 As shown in Table 1, the conditions for salting treatment (concentration of saline solution, temperature) were changed. Otherwise in the same manner as in Example 2, the hollow fiber membranes of Examples 3 to 6 were produced.
[0107] 〔実施例 7〕 [Example 7]
表 1 に示されるように、
Figure imgf000024_0002
比が変更された。 それ以外は実施例 2と 同様にして、 実施例 7の中空糸膜が製造された。
As shown in Table 1,
Figure imgf000024_0002
The ratio has changed. A hollow fiber membrane of Example 7 was produced in the same manner as in Example 2 except for the above.
[0108] 〔実施例 8〕 [Example 8]
表 1 に示されるように、 紡糸工程の延伸倍率 ( 〇滞留時間) が変更され た。 それ以外は実施例 2と同様にして、 実施例 8の中空糸膜が製造された。 なお、 延伸倍率の変更は、 ノズル開口部の断面積を〇. 0 5〇1〇1 2から 0 . 0 7 2に変更する (ノズルの外径およびスリツ ト幅を大きくすることによりAs shown in Table 1, the draw ratio (○ residence time) in the spinning process was changed. Otherwise in the same manner as in Example 2, the hollow fiber membrane of Example 8 was produced. Note that changing the draw ratio, the cross-sectional area of the nozzle opening 0.0 5_Rei_1_rei_1 change 2 0. 0 7 2 (by increasing the outside diameter and Suritsu-wide nozzle
、 ノズルの開口部 (原料溶液吐出孔) の断面積を大きくする) ことによって 行った。 , By increasing the cross-sectional area of the nozzle opening (raw material solution discharge hole).
[0109] 〔実施例 9〕 [Example 9]
表 1 に示されるように、 原料溶液の
Figure imgf000024_0003
凝固条件、 熱水処理条件 および塩漬処理条件が変更された。 それ以外は、 実施例 8と同様にして、 実 施例 9の中空糸膜が製造された。
As shown in Table 1,
Figure imgf000024_0003
The coagulation conditions, hot water treatment conditions, and salt treatment conditions were changed. The hollow fiber membrane of Example 9 was produced in the same manner as Example 8 except for the above.
[01 10] 〔実施例 1 〇〕 [01 10] [Example 10]
表 1 に示されるように、 原料溶液のポリマー濃度、 凝固条件が変更された 。 それ以外は、 実施例 9と同様にして、 実施例 1 0の中空糸膜が製造された 〇 2020/175375 23 卩(:171? 2020 /007080 As shown in Table 1, the polymer concentration of the raw material solution and the coagulation conditions were changed. Otherwise in the same manner as in Example 9, the hollow fiber membrane of Example 10 was produced. 〇 2020/175 375 23 卩 (: 171-1? 2020 /007080
[0111] 〔比較例 1〕 [0111] [Comparative Example 1]
塩漬処理が行われなかった点以外は実施例 1 と同様にして、 比較例 1の中 空糸膜が製造された。 A hollow fiber membrane of Comparative Example 1 was produced in the same manner as in Example 1 except that the salting treatment was not performed.
[0112] 〔比較例 2〕 [0112] [Comparative Example 2]
表 1 に示されるように、 紡糸工程の延伸倍率が変更された。 それ以外は実 施例 1 と同様にして、 比較例 2の中空糸膜が製造された。 なお、 延伸倍率の 変更は、 ノズルの断面積を 0. 05〇11112から 0. 04〇11112に変更する (ノ ズルの外径およびスリッ ト幅を小さくすることにより、 ノズルの開口部 (原 料溶液吐出孔) の断面積を小さくする) ことによって行った。 As shown in Table 1, the draw ratio in the spinning process was changed. A hollow fiber membrane of Comparative Example 2 was produced in the same manner as in Example 1 except for the above. To change the draw ratio, change the cross-sectional area of the nozzle from 0.05 〇 1111 2 to 0.04 〇 1111 2 (By reducing the outer diameter and slit width of the nozzle, the nozzle opening ( The cross-sectional area of the raw material solution discharge hole) was reduced).
[0113] 〔比較例 3〕 [0113] [Comparative Example 3]
表 1 に示されるように、
Figure imgf000025_0001
比が変更された。 また、 低粘度<3丁八を 用いた。 それ以外は比較例 1 と同様にして、 比較例 3の中空糸膜が製造され た。
As shown in Table 1,
Figure imgf000025_0001
The ratio has changed. A low viscosity <3-8 was used. A hollow fiber membrane of Comparative Example 3 was produced in the same manner as in Comparative Example 1 except for the above.
[0114] 〔比較例 4〕 [0114] [Comparative Example 4]
表 1 に示されるように、
Figure imgf000025_0002
凝固条件、 延伸倍率および熱水処理の 条件が変更された。 それ以外は比較例 1 と同様にして、 比較例 4の中空糸膜 が製造された。
As shown in Table 1,
Figure imgf000025_0002
The coagulation conditions, draw ratio and hot water treatment conditions were changed. A hollow fiber membrane of Comparative Example 4 was produced in the same manner as in Comparative Example 1 except for the above.
[0115] 〔比較例 5〕 [0115] [Comparative Example 5]
表 1 に示されるように、
Figure imgf000025_0003
3比および熱水処理の条件が変更された。 それ以外は、 比較例 4と同様にして、 比較例 5の中空糸膜が製造された。
As shown in Table 1,
Figure imgf000025_0003
3 Ratio and hot water treatment conditions changed. A hollow fiber membrane of Comparative Example 5 was produced in the same manner as Comparative Example 4 except for the above.
[0116] 〔比較例 6〕 [0116] [Comparative Example 6]
表 1 に示されるように、
Figure imgf000025_0004
比、 熱水処理および塩漬処理の条件が変 更された。 それ以外は比較例 5と同様にして、 比較例 6の中空糸膜が製造さ れた。
As shown in Table 1,
Figure imgf000025_0004
The ratio, hydrothermal treatment and salting treatment conditions were changed. A hollow fiber membrane of Comparative Example 6 was produced in the same manner as in Comparative Example 5 except for the above.
[0117] <ラマン値の測定> [0117] <Measurement of Raman value>
実施例 1〜 1 0および比較例 1〜 6の中空糸膜について、 ラマン値を測定 した。 ラマン値は、 実施形態で説明した測定法によって以下の条件で測定さ れた。 ラマン値の測定結果を表 1 に示す。 Raman values of the hollow fiber membranes of Examples 1 to 10 and Comparative Examples 1 to 6 were measured. The Raman value is measured under the following conditions by the measuring method described in the embodiment. It was Table 1 shows the Raman measurement results.
[0118] (ラマン値の測定条件) [0118] (Raman measurement conditions)
中空糸膜 1本を氷包埋し、 ミクロトームで断面を作製した。 作製した断面 試料を水に浸潰し、 断面が水面からわずかに出た状態で、 顕微ラマン分光装 置 (ナノフォトン社製レーザーラマン顕微鏡: RAMAN— 1 1) を用いて 、 レーザー波長 532 n m、 レーザー強度約 2. 2 mW、 アパーチャー径 1 00 Mm、 露光時間 8秒、 露光回数 1回、 回折格子 60 O g r/mm、 対物 レンズ 50倍/ N A0. 55、 走査間隔 1. 0 Mmの条件でマッピング分析 (ラマンスペクトルの測定) を行った。 なお、 ラマン値の測定は、 膜断面の どの部分 (膜厚の薄い部分または厚い部分) で測定してもよいが、 最も厚い 部分 (おにぎりの辺の中央部分) について測定した。 A hollow fiber membrane was embedded in ice and a cross section was prepared with a microtome. The prepared cross section The sample was immersed in water, and the cross section was slightly exposed from the surface of the water. Using a Raman microscope (nanophoton laser Raman microscope: RAMAN— 11), laser wavelength 532 nm, laser Intensity of about 2.2 mW, aperture diameter of 100 Mm, exposure time of 8 seconds, number of exposures 1 time, diffraction grating 60 O gr/mm, objective lens 50x/NA 0.55, scan interval 1.0 Mm Mapping analysis (measurement of Raman spectrum) was performed. The Raman value may be measured at any part of the film cross section (thin or thick part), but it was measured at the thickest part (center part of the side of the rice ball).
[0119] ラマンスペクトルにおける 2935 c m-1付近のピークの強度を、 顕微ラ マン分光装置に付属のピーク面積算出ソフトを用いて算出した。 2800〜 3 1 00 c m-1をべースラインとし、 ピークの頂点を中心とし、 ピークの幅 を 22. 2 c m-1に固定し、 口ーレンツ関数を用いてフィッティングをおこ ない、 算出されたピーク面積を信号強度 (ピーク強度) とした (図 9参照) [0119] The intensity of the peak in the vicinity of 2935 cm- 1 in the Raman spectrum was calculated using the peak area calculation software attached to the micro Raman spectroscope. And 2800~ 3 1 00 c m- 1 the baseline, centered on top of the peak, to fix the width of the peak 22. to 2 c m-1, not to put a fitting with a mouth Rentsu function was calculated The peak area was used as the signal intensity (peak intensity) (see Fig. 9).
[0120] <形状に関するパラメータの測定> [0120] <Measurement of parameters related to shape>
実施例 1〜 1 0および比較例 1〜 6の中空糸膜 (塩漬処理後の状態。 ただ し、 塩漬処理を行わなかった場合は熱水処理後の状態) について、 外径 (〇 D) 、 内径 (丨 D) および中空率 (H) を以下のようにして測定した。 その 結果、 実施例 1〜 1 0および比較例 1〜 6の中空糸膜の ODは 200 Mmで あり、 丨 0は90 〇1であり、 Hは 20. 3 %であった。 Regarding the hollow fiber membranes of Examples 1 to 10 and Comparative Examples 1 to 6 (the state after the salting treatment, but the state after the hot water treatment without the salting treatment), the outer diameter (○ D ), inner diameter (D) and hollow ratio (H) were measured as follows. As a result, the ODs of the hollow fiber membranes of Examples 1 to 10 and Comparative Examples 1 to 6 were 200 Mm, 0 was 9001, and H was 20.3%.
[0121] (内径、 外径の測定) [0121] (Measurement of inner diameter and outer diameter)
中空糸膜の内径、 外径および膜厚は、 中空糸膜をスライ ドグラスの中央に 開けられた直径 3 mmの孔に中空糸膜が抜け落ちない程度に適当本数通し、 スライ ドグラスの上下面に沿ってカミソリにより中空糸膜をカッ トし、 中空 糸膜断面サンプルを得た後、 投影機 (N i k o n P RO F I L E P RO 〇 2020/175375 25 卩(:171? 2020 /007080 For the inner diameter, outer diameter and thickness of the hollow fiber membrane, pass the appropriate number of hollow fiber membranes through the hole of 3 mm in diameter in the center of the slide glass so that the hollow fiber membranes do not fall out, and follow the upper and lower surfaces of the slide glass. After cutting the hollow fiber membrane with a razor to obtain a cross section of the hollow fiber membrane, the projector (N ikon P RO FILEP RO 〇 2020/175 375 25 卩 (: 171-1? 2020 /007080
」 巳(3丁〇[¾ V - 1 2) を用いて中空糸膜断面の短径、 長径を測定するこ とにより得られる。 外径については、 中空糸膜断面 1個につき 2方向の短径 、 長径を測定し、 算術平均値を中空糸膜断面 1個の外径とした。 また、 内径 については、 おにぎりに外接する長方形の長辺と短辺の長さを測定し、 算術 平均値を中空糸膜断面 1個の内径とした。 最大および最小を含む 1 0断面に ついて同様に測定を行い、 平均値を内径および外径とした。 It can be obtained by measuring the minor axis and major axis of the cross section of the hollow fiber membrane using a Mitsu (3 〇 [¾ V-12)). Regarding the outer diameter, the minor axis and major axis in two directions were measured per hollow fiber membrane cross section, and the arithmetic mean value was taken as the outer diameter of one hollow fiber membrane cross section. Regarding the inner diameter, the length of the long side and the short side of the rectangle circumscribing the rice ball was measured, and the arithmetic mean value was taken as the inner diameter of one hollow fiber membrane cross section. The same measurement was performed on the 10 cross section including the maximum and minimum, and the average values were taken as the inner diameter and the outer diameter.
[0122] (中空率の測定方法) [0122] (Method of measuring hollowness)
中空糸膜断面サンプルの写真撮影をマイクロスコープ<巳丫巳 1\1〇巳 V 1~1乂_ 1 0 0 0を用いて行い、 上記マイクロスコープの面積測定機能により 中空糸膜の中空部の断面積 (中空部断面積) と、 中空糸膜の膜部の断面積 ( 中空部断面積) を求め、 次式より中空率を算出した。 Photographs of cross-sections of hollow fiber membranes were taken using a microscope <Minami V 1 ~ 1 V V 1 ~ 1 _ 1_100, and the area measurement function of the above-mentioned microscope was used to measure the hollow portion of the hollow fiber membrane. The cross-sectional area (hollow portion cross-sectional area) and the cross-sectional area of the membrane portion of the hollow fiber membrane (hollow portion cross-sectional area) were obtained, and the hollow ratio was calculated from the following formula.
中空率 (%) =中空部断面積/ (膜部断面積十中空部断面積) X I 0 0 Hollow ratio (%) = hollow area cross-sectional area / (membrane cross-sectional area + hollow area cross-sectional area) X I 0 0
[0123] <内径収縮率の測定> [0123] <Measurement of inner diameter shrinkage>
実施例 1〜 1 0および比較例 1〜 6の中空糸膜について、 以下のようにし て内径収縮率を測定した。 内径収縮率の測定結果は表 1 に示される。 With respect to the hollow fiber membranes of Examples 1 to 10 and Comparative Examples 1 to 6, the inner diameter shrinkage ratio was measured as follows. Table 1 shows the measurement results of inner diameter shrinkage.
[0124] まず、 図 5に示されるような有効長 2 4 . 5 ± 0 .
Figure imgf000027_0001
[0124] First, the effective length 24.5 ± 0.
Figure imgf000027_0001
充填率が 2 5 . 0 ± 1 . 0 %となるように複数の中空糸膜を束ねて充填し、 該中空糸膜束と 3 II 3管の端部を樹脂により接着し、 接着樹脂端部を切削し て中空糸膜の中空部を開口させることにより、 中空糸膜モジュール 1が作製 された。 A plurality of hollow fiber membranes are bundled and packed so that the filling rate becomes 25.0 ± 1.0%, and the hollow fiber membrane bundle and the end of the tube 3 II 3 are adhered with resin, and the adhesive resin end The hollow fiber membrane module 1 was prepared by cutting the hollow fiber membrane to open the hollow portion of the hollow fiber membrane.
[0125] 作製された中空糸膜モジュール 1 について、 リークがないことを確認した 。 具体的には、 中空糸膜モジュール 1 を水中に沈め、 中空糸膜外側を一方の 開口部から空気で加圧し、 中空糸膜外側の他方の開口部を封止する。 開口部 よりエアーが出ていなければ、 リーク無しと判断した。 [0125] It was confirmed that the manufactured hollow fiber membrane module 1 had no leak. Specifically, the hollow fiber membrane module 1 is submerged in water, the outside of the hollow fiber membrane is pressurized with air from one opening, and the other opening outside the hollow fiber membrane is sealed. If no air came out from the opening, it was judged that there was no leak.
[0126] また、 作製された中空糸膜モジュール 1 について、 性能 ([¾〇性能) 確認 試験を行った。 具体的には、 中空糸膜モジュール 1 を用いて [¾〇試験 (中空 糸膜外側の圧力: 5 .
Figure imgf000027_0002
中空糸膜外側の流入口 1 0 1 3における試 験液の
Figure imgf000027_0003
I濃度: 3 5 0 0 0 9 / 1_ , 対象溶液の温度: 2 5 °〇, 回収 〇 2020/175375 26 卩(:171? 2020 /007080
[0126] Further, a performance ([¾ performance) confirmation test was performed on the manufactured hollow fiber membrane module 1. Specifically, using the hollow fiber membrane module 1, [¾ 〇 test (pressure on the outside of the hollow fiber membrane: 5.
Figure imgf000027_0002
Of the test solution at the inlet 1 0 1 3 outside the hollow fiber membrane
Figure imgf000027_0003
I concentration: 350 0 9 / 1_, temperature of target solution: 25 ° 〇, recovery 〇 2020/175 375 26 卩 (: 171-1? 2020 /007080
率 : 1 0 %) を行い、 透過水量 ( [¾) および塩除去率 ([¾」) が 、 中空糸膜 (! 1 ) の性能基準から逸脱していないことを確認した。 例えば 、 通常の逆浸透膜を基準と考えた場合、 は好ましくは 4 5
Figure imgf000028_0001
日以 上である。 また、
Figure imgf000028_0002
」は好ましくは 9 0 %以上、 より好ましくは 9 5 %以上 、 さらに好ましくは 9 9 %以上である。
It was confirmed that the permeated water amount ([¾) and the salt removal rate ([¾]) did not deviate from the performance standard of the hollow fiber membrane (! 1 ). For example, when considering a standard reverse osmosis membrane as a standard,
Figure imgf000028_0001
More than a day. Also,
Figure imgf000028_0002
Is preferably 90% or more, more preferably 95% or more, and further preferably 99% or more.
[0127] 上記のようにして性能に問題ないことが確認された中空糸膜モジュール 1 (図 5に示されるような 3 II 3製の容器内に中空糸膜が収容されたモジュー ル) を使用して、 実施形態で説明された所定の膜分離方法を実施する巳〇試 験を行った。 [0127] The hollow fiber membrane module 1 (a module in which the hollow fiber membrane is housed in a container made of 3 II 3 as shown in Fig. 5) was confirmed to have no performance problems as described above. Then, a test was conducted to carry out the predetermined membrane separation method described in the embodiment.
[0128] 中空糸膜の内側および外側への送液には、 液体クロマトグラフィー用のポ ンプ 3 2 , 3 3を使用した。 中空糸膜内側の流入口 (第 2液流入口 1 0 1 3 ) における圧力が〇.
Figure imgf000028_0003
中空糸膜外側の流入口 (第 1液供給 口 1 0 0 3) における流量が
Figure imgf000028_0005
1 圧力が 5 .
Figure imgf000028_0004
となる ように、 ポンプ 3 2 , 3 3の運転条件を設定した。
[0128] Liquid chromatography pumps 3 2 and 3 3 were used for feeding the liquid inside and outside the hollow fiber membrane. The pressure at the inlet (second liquid inlet 1 0 1 3) inside the hollow fiber membrane is ◯.
Figure imgf000028_0003
The flow rate at the inlet (first liquid supply port 103) outside the hollow fiber membrane is
Figure imgf000028_0005
1 pressure is 5.
Figure imgf000028_0004
The operating conditions of pumps 3 2 and 3 3 were set so that
[0129] ポンプ 3 2 , 3 3の運転開始時は、 第 1液および第 2液 (第 1液および第 [0129] At the start of operation of pumps 32 and 33, the first liquid and the second liquid (first liquid and
2液は同じ液であり、 それらの浸透圧差は 0 1\/1 3である) として供給され るタンク 3 4内の液の濃度は 1 0質量%に調整し、 ポンプの運転開始から 1 0分後までにタンク 3 4に濃塩水を添加し、 タンク 3 4内の液の濃度を 1 5 質量%とした。 1 5質量%に達した時点を 0時間 (巳〇試験開始時) とし、 連続的に巳(3試験を実施した。 巳(3試験の実施中、 中空糸膜内側の流入口 ( 第 2液流入口 1 0 1 3) における圧力は〇. 1 IV! 3に維持され、 中空糸膜 外側の流出口 (第 1液排出口 1 0 0 13) における圧力は〇.
Figure imgf000028_0006
The two liquids are the same liquid, and the osmotic pressure difference between them is 0 1\/1 3 ). The concentration of the liquid in tank 34 is adjusted to 10% by mass, and 10% from the start of pump operation. Concentrated salt water was added to the tank 34 by the minute, and the concentration of the liquid in the tank 34 was adjusted to 15% by mass. The time when the amount reached 15% by mass was set as 0 hour (at the beginning of the test), and the test was continuously carried out (3 tests were carried out. The pressure at the inlet 1 0 1 3) is maintained at 0.1 IV! 3 and the pressure at the outlet (first liquid outlet 1 0 13) outside the hollow fiber membrane is 0.
Figure imgf000028_0006
るように維持された。 また、 タンク 3 4内の液の温度は 2 5 ± 1 °〇に維持し た。 温度変化が大きくなると流量変化が生じるため好ましくない。 Was maintained. The temperature of the liquid in tank 34 was maintained at 25 ± 1 ° . If the temperature changes greatly, the flow rate changes, which is not preferable.
[0130] なお、 図 5に示されるように、 中空糸膜外側の流入口 1 0 0 3に供給され る第 1液と中空糸膜内側の流入口 1 0 1 3に供給される第 2液はタンク 3 4 から供給される同じ液であり、 中空糸膜モジュール 1で濃縮された第 1液と 希釈された第 2液とはタンク 3 4で混合され、 再度同じ液として中空糸膜外 〇 2020/175375 27 卩(:171? 2020 /007080 [0130] As shown in Fig. 5, the first liquid supplied to the inflow port 1003 outside the hollow fiber membrane and the second liquid supplied to the inflow port 1013 inside the hollow fiber membrane. Is the same liquid supplied from the tank 34, and the first liquid concentrated in the hollow fiber membrane module 1 and the diluted second liquid are mixed in the tank 34, and again as the same liquid outside the hollow fiber membrane. 〇 2020/175 375 27 卩 (: 171-1? 2020 /007080
側の流入口 1 0 0 3と中空糸膜内側の流入口 1 0 1 3とに供給される。 It is supplied to the side inflow port 1003 and the inflow port 1013 inside the hollow fiber membrane.
[0131 ] 巳〇試験開始から 1、 2 4、 4 8、 7 2および 9 6時間経過後における中 空糸膜の内径収縮率を測定した。 具体的には、 各時間において、 中空糸膜内 側の流入口 1 0 1 3における流量と流出口 1 0 1 13における流量とを測定し 、 中空糸膜内側の流入口 1 〇 1 3における流量と流出口 1 0 1 13における流 量との平均値 (中空糸膜内平均流量) を算出する。 [0131] The inner diameter shrinkage ratio of the hollow fiber membrane was measured after 1, 2, 4, 48, 72 and 96 hours from the start of the test. Specifically, at each time, the flow rate at the inflow port 10 13 inside the hollow fiber membrane and the flow rate at the outflow port 10 11 13 were measured, and the flow rate at the inflow port 10 13 inside the hollow fiber membrane was measured. Calculate the average value (the average flow rate in the hollow fiber membrane) of the flow rate at the outlet and the outlet 101.
[0132] 次に、 巳〇試験開始から 1時間後の中空糸膜内平均流量に対する各時間の 中空糸膜内平均流量の比率を中空糸膜内平均流量の減少率として算出した。 図 4に、 実施例 1、 2および比較例 2の中空糸膜について、 巳(3試験開始か らの経過時間と中空糸膜内の平均流量の変化比率との関係をグラフで示す。 なお、 巳〇試験開始から 1時間後の中空糸膜の内径を減少率の基準としたの は、 1時間経過した場合、 膜内の濃度分布等が十分に安定していると考えら れるからであり、 便宜上、 巳(3試験開始から 1時間後の中空糸膜の内径を中 空糸膜の使用開始時の内径とみなしたからである。 [0132] Next, the ratio of the average flow rate in the hollow fiber membrane at each time to the average flow rate in the hollow fiber membrane one hour after the start of the test was calculated as the reduction rate of the average flow rate in the hollow fiber membrane. FIG. 4 is a graph showing the relationship between the elapsed time from the start of the test and the change ratio of the average flow rate in the hollow fiber membranes of the hollow fiber membranes of Examples 1 and 2 and Comparative Example 2. † The inner diameter of the hollow fiber membrane 1 hour after the start of the test was used as the standard for the reduction rate because it is considered that the concentration distribution in the membrane is sufficiently stable after 1 hour. For the sake of convenience, Mitsumi (3 The inner diameter of the hollow fiber membrane 1 hour after the start of the test was regarded as the inner diameter at the start of use of the hollow fiber membrane.
[0133] 実施形態で説明したように、 ^96010 ^61^ 式より、 中空糸膜内平均流 量の減少率から、 内径 ( I 0) 収縮率を算出した。 [0133] As described in the embodiment, the inner diameter (I 0) shrinkage ratio was calculated from the decrease rate of the average flow rate in the hollow fiber membrane from the ^96010 ^61^ equation.
[0134] なお、 比較例 4〜 6の中空糸膜については、 5 .
Figure imgf000029_0001
の耐圧性を有し ていないため、 巳〇試験を実施することができなかった。
[0134] For the hollow fiber membranes of Comparative Examples 4 to 6, 5.
Figure imgf000029_0001
Since it does not have pressure resistance, it was not possible to carry out the Minoo test.
[0135] 表 1 には、 参考として、 2 4 0時間経過後の中空糸 (膜) の内側および外 側の流入口での流量および圧力と、 中空糸 (膜) 内側の送液に必要なエネル ギー (比較例 1 に対する比率) を併せて示す。 [0135] As a reference, Table 1 shows the flow rates and pressures at the inner and outer inlets of the hollow fiber (membrane) after 240 hours, and the required flow rate inside the hollow fiber (membrane). The energy (ratio to Comparative Example 1) is also shown.
[0136]
Figure imgf000030_0001
[0136]
Figure imgf000030_0001
Figure imgf000030_0002
Figure imgf000030_0002
〇 2020/175375 29 卩(:171? 2020 /007080 〇 2020/175 375 29 卩 (:171? 2020 /007080
[0137] 表 1および図 4に示される結果から、 比較例の中空糸膜を用いた場合、 同 —圧力下における中空糸膜内平均流量は、 巳〇試験により経時的に低下し、 中空糸膜の内径が経時的に減少することが分かる。 ここで、 比較例について 、 9 6時間使用された後の中空糸膜の内径の収縮率は、 使用開始時の内径に 対して 9 %以上であった。 [0137] From the results shown in Table 1 and Fig. 4, when the hollow fiber membranes of Comparative Examples were used, the average flow rate inside the hollow fiber membranes under the same pressure decreased with time in the test of It can be seen that the inner diameter of the membrane decreases over time. Here, in the comparative example, the shrinkage ratio of the inner diameter of the hollow fiber membrane after being used for 96 hours was 9% or more with respect to the inner diameter at the start of use.
[0138] これに対して、 実施例の中空糸膜を用いた場合、 同一圧力下における中空 糸膜内平均流量の経時的な低下は比較例よりも少なく、 中空糸膜の内径の経 時的な減少が抑制されていることが分かる。 そして、 実施例について、 9 6 時間使用された後の中空糸膜の内径の収縮率は、 使用開始時の内径に対して 9 %未満であり、 比較例に対して中空糸膜の内径の経時的な収縮が抑制され ていることが分かる。 [0138] On the other hand, when the hollow fiber membranes of Examples were used, the average flow rate in the hollow fiber membranes under the same pressure did not decrease with time, and the inner diameter of the hollow fiber membranes changed with time. It can be seen that the large decrease is suppressed. The shrinkage ratio of the inner diameter of the hollow fiber membrane after being used for 96 hours was less than 9% with respect to the inner diameter at the start of use, and the aging time of the inner diameter of the hollow fiber membrane was changed with respect to the comparative example. It can be seen that the contraction is suppressed.
[0139] 今回開示された実施形態および実施例はすべての点で例示であって制限的 なものではないと考えられるべきである。 本発明の範囲は上記した説明では なくて請求の範囲によって示され、 請求の範囲と均等の意味および範囲内で のすベての変更が含まれることが意図される。 The embodiments and examples disclosed this time must be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description but by the scope of the claims, and is intended to include meanings equivalent to the scope of the claims and all modifications within the scope.
符号の説明 Explanation of symbols
[0140] 1 中空糸膜モジユール、 1 0 中空糸膜、 1 〇 3 第 1開口部、 1 0匕 第 2開口部、 1 1 第 1室、 1 2 第 2室、 1 3 , 1 4 壁部材、 1 0 0 中空糸膜の外側、 1 0 0 3 第 1液供給口、 1 0 0匕 第 1液排出口、 1 〇 1 3 第 2液供給口、 1 0 1 匕 第 2液排出口、 2 芯管、 2 1 孔、 3 0 , 3 2 , 3 3 ポンプ、 3 1 高圧ポンプ、 3 4 タンク、 4 分流弁、 [0140] 1 Hollow Fiber Membrane Module, 1 0 Hollow Fiber Membrane, 1 0 3 1st Opening, 10 sq 2nd Opening, 1 1 1st Chamber, 1 2 2nd Chamber, 1 3, 1 4 Wall Member , 1 0 0 Outside of hollow fiber membrane, 1 0 0 3 1st liquid supply port, 1 0 0 1st liquid 1st discharge port, 1 0 1 3 2nd liquid supply port, 1 0 1 1st liquid 2nd liquid discharge port, 2 core tube, 2 1 hole, 3 0, 3 2 ,3 3 pump, 3 1 high pressure pump, 3 4 tank, 4 diversion valve,
6 2 保持部材、 6 2 3 〇ーリング、 6 1 樹脂壁、 7 圧力容器、 8 0 原料溶液、 8 1 ノズル、 8 2 , 8 3 , 8 4 , 8 5 口ーラー、 8 6 中 空糸膜、 9 1 凝固液、 9 2 熱水、 9 3 塩水。 6 2 Holding member, 6 2 3 o ring, 6 1 resin wall, 7 pressure vessel, 8 0 raw material solution, 8 1 nozzle, 8 2 ,8 3 ,8 4 ,8 5 mouth roller, 8 6 hollow fiber membrane, 9 1 coagulation liquid, 9 2 hot water, 9 3 brine.

Claims

〇 2020/175375 30 卩(:171? 2020 /007080 請求の範囲 〇 2020/175375 30 units (: 171? 2020/007080 Claims
[請求項 1 ] 中空糸型の半透膜である中空糸膜であって、 [Claim 1] A hollow fiber membrane which is a hollow fiber type semipermeable membrane,
所定の膜分離方法に 9 6時間使用された後の前記中空糸膜の内径の 収縮率が、 使用開始時の内径に対して 0 . 1 %以上 9 %未満であり、 前記所定の膜分離方法は、 前記中空糸膜と、 前記中空糸膜で仕切ら れた第 1室および第 2室と、 を有する中空糸膜モジユールを用いて、 第 1液を第 1圧力で前記第 1室に流し、 第 2液を前記第 1圧力よりも 低い第 2圧力で前記第 2室に流すことで、 前記第 1室内の前記第 1液 に含まれる溶媒を前記中空糸膜を介して前記第 2室内の前記第 2液に 移行させ、 前記第 1室から濃縮された前記第 1液である濃縮液を排出 し、 前記第 2室から希釈された前記第 2液である希釈液を排出し、 前記中空糸膜の外側の空間が前記第 1室であり、 前記中空糸膜の内 側の空間が前記第 2室であり、 The shrinkage ratio of the inner diameter of the hollow fiber membrane after being used for a predetermined membrane separation method for 96 hours is 0.1% or more and less than 9% with respect to the inner diameter at the start of use. Using a hollow fiber membrane module having the hollow fiber membrane and a first chamber and a second chamber partitioned by the hollow fiber membrane, a first liquid is caused to flow into the first chamber at a first pressure, By flowing the second liquid into the second chamber at a second pressure lower than the first pressure, the solvent contained in the first liquid in the first chamber is transferred to the second chamber through the hollow fiber membrane. Transfer to the second liquid, discharge the concentrated liquid that is the concentrated first liquid from the first chamber, discharge the diluted liquid that is the diluted second liquid from the second chamber, the hollow The space outside the fiber membrane is the first chamber, the space inside the hollow fiber membrane is the second chamber,
前記第 1圧力が 5 .
Figure imgf000032_0001
前記第 2圧力が一定であり、 前記第 1液と前記第 2液の浸透圧差が 0 !\/1 3である、 中空糸膜。
The first pressure is 5.
Figure imgf000032_0001
The second pressure is constant, osmotic pressure difference of the second liquid and the first liquid is 0! \ / 1 3, the hollow fiber membrane.
[請求項 2] 前記中空糸膜の内径が 4 0 以上 2 0 0 以下である、 請求項 2. The hollow fiber membrane has an inner diameter of 40 or more and 200 or less.
1 に記載の中空糸膜。 The hollow fiber membrane according to 1.
[請求項 3] 前記中空糸膜のラマン値が 7 2 %以上 9 0 %以下である、 請求項 1 または 2に記載の中空糸膜。 [Claim 3] The hollow fiber membrane according to claim 1 or 2, wherein the hollow fiber membrane has a Raman value of 72% or more and 90% or less.
[請求項 4] 前記中空糸膜の断面内形が三角形状である、 請求項 1〜 3のいずれ か 1項に記載の中空糸膜。 [Claim 4] The hollow fiber membrane according to any one of claims 1 to 3, wherein the hollow fiber membrane has a triangular cross-section.
[請求項 5] セルロース系樹脂、 ポリスルホン系樹脂およびポリアミ ド系樹脂の 少なくともいずれかを含む材料から構成される、 請求項 1〜 4のいず れか 1項に記載の中空糸膜。 [Claim 5] The hollow fiber membrane according to any one of claims 1 to 4, which is composed of a material containing at least one of a cellulose resin, a polysulfone resin, and a polyamide resin.
[請求項 6] 前記中空糸膜と、 前記中空糸膜で仕切られた第 1室および第 2室と [Claim 6] The hollow fiber membrane, and a first chamber and a second chamber partitioned by the hollow fiber membrane
、 を有する中空糸膜モジユールを用いて、 第 1液を第 1圧力で前記第 1室に流し、 第 2液を前記第 1圧力よりも低い第 2圧力で前記第 2室 に流すことで、 前記第 1室内の前記第 1液に含まれる溶媒を前記中空 〇 2020/175375 31 卩(:171? 2020 /007080 By using a hollow fiber membrane module having, a first liquid is caused to flow into the first chamber at a first pressure, and a second liquid is caused to flow into the second chamber at a second pressure lower than the first pressure, The solvent contained in the first liquid in the first chamber is made hollow. 〇 2020/175 375 31 卩 (: 171-1? 2020 /007080
糸膜を介して前記第 2室内の前記第 2液に移行させ、 前記第 1室から 濃縮された前記第 1液である濃縮液を排出し、 前記第 2室から希釈さ れた前記第 2液である希釈液を排出し、 前記第 1液と前記第 2液の浸 透圧差が 4 IV! 3以下である、 膜分離方法に用いられる、 請求項 1〜 5のいずれか 1項に記載の中空糸膜。 It is transferred to the second liquid in the second chamber through a thread membrane, the concentrated liquid which is the concentrated first liquid is discharged from the first chamber, and the second liquid diluted from the second chamber is discharged. The diluted liquid, which is a liquid, is discharged, and the osmotic pressure difference between the first liquid and the second liquid is 4 IV! 3 or less, which is used in a membrane separation method, The method according to any one of claims 1 to 5. Hollow fiber membrane.
[請求項 7] 原料溶液をノズルから空中走行部を経て凝固液中に吐出して、 前記 原料溶液の凝固物を前記凝固液中から曳き出すことにより、 中空糸型 の半透膜である中空糸膜を得る、 紡糸工程と、 [Claim 7] The raw material solution is discharged into the coagulation liquid from the nozzle through the air traveling section, and the coagulated product of the raw material solution is pulled out from the coagulation liquid to form a hollow fiber-type semipermeable membrane. To obtain a yarn film, a spinning process,
前記紡糸工程で得られた中空糸膜を水洗した後に、 熱水処理および塩 潰処理に供する、 後処理工程と、 After washing the hollow fiber membrane obtained in the spinning step with water, it is subjected to hot water treatment and salt treatment, a post-treatment step,
を含む中空糸膜の製造方法であって、 A method for producing a hollow fiber membrane comprising:
前記原料溶液は溶媒および非溶媒を含み、 前記原料溶液中の溶媒/ 非溶媒の質量比が 5 0 / 5 0〜 7 0 / 3 0であり、 The raw material solution contains a solvent and a non-solvent, the mass ratio of the solvent / non-solvent in the raw material solution is 50/50 ~ 70 / 30,
前記紡糸工程において、 前記ノズルの出口における原料溶液の吐出 速度に対する曳き出し速度の比率である延伸倍率が 2 . 1〜 5 . 0で あり、 In the spinning step, the draw ratio, which is the ratio of the drawing speed to the discharge speed of the raw material solution at the outlet of the nozzle, is 2.1 to 5.0,
前記塩漬処理の温度が 7 0 °〇以上 9 5 °〇以下である、 製造方法。 A manufacturing method, wherein the temperature of the salting treatment is not less than 70° and not more than 95°.
[請求項 8] 請求項 7に記載の製造方法により製造される中空糸膜。 [Claim 8] A hollow fiber membrane produced by the production method according to claim 7.
[請求項 9] 請求項 1〜 6および 8のいずれか 1項に記載の中空糸膜と、 前記中 空糸膜で仕切られた第 1室および第 2室と、 を有する、 中空糸膜モジ ュ _ル。 [Claim 9] A hollow fiber membrane module, comprising: the hollow fiber membrane according to any one of claims 1 to 6 and 8; and a first chamber and a second chamber partitioned by the hollow fiber membrane. __ .
[請求項 10] 請求項 9に記載の中空糸膜モジュールを備える膜分離装置であって 前記第 1液を第 1圧力で前記第 1室に流し、 前記第 2液を前記第 1 圧力よりも低い第 2圧力で前記第 2室に流すことで、 前記第 1室内の 前記第 1液に含まれる溶媒を前記中空糸膜を介して前記第 2室内の前 記第 2液に移行させ、 前記第 1室から濃縮された前記第 1液である濃 縮液を排出し、 前記第 2室から希釈された前記第 2液である希釈液を 〇 2020/175375 32 卩(:171? 2020 /007080 [Claim 10] A membrane separation device comprising the hollow fiber membrane module according to claim 9, wherein the first liquid is caused to flow into the first chamber at a first pressure, and the second liquid is more than the first pressure. By flowing into the second chamber at a low second pressure, the solvent contained in the first liquid in the first chamber is transferred to the second liquid in the second chamber through the hollow fiber membrane, The concentrated liquid that is the first liquid concentrated is discharged from the first chamber, and the diluted liquid that is the second liquid diluted from the second chamber is discharged. 〇 2020/175 375 32 (:171? 2020/007080
排出し、 Discharge
前記中空糸膜の外側の空間が前記第 1室であり、 前記中空糸膜の内 側の空間が前記第 2室であり、 The outer space of the hollow fiber membrane is the first chamber, the inner space of the hollow fiber membrane is the second chamber,
前記第 1液と前記第 2液の浸透圧差が 4 IV! 3以下である、 膜分離 装置。 The membrane separation device, wherein the osmotic pressure difference between the first liquid and the second liquid is 4 IV! 3 or less.
[請求項 1 1 ] 請求項 9に記載の中空糸膜モジュールを用いる膜分離方法であって 前記第 1液を第 1圧力で前記第 1室に流し、 前記第 2液を前記第 1 圧力よりも低い第 2圧力で前記第 2室に流すことで、 前記第 1室内の 前記第 1液に含まれる溶媒を前記中空糸膜を介して前記第 2室内の前 記第 2液に移行させ、 前記第 1室から濃縮された前記第 1液である濃 縮液を排出し、 前記第 2室から希釈された前記第 2液である希釈液を 排出し、 [Claim 11] A membrane separation method using the hollow fiber membrane module according to claim 9, wherein the first liquid is caused to flow into the first chamber at a first pressure, and the second liquid is discharged from the first pressure. By flowing into the second chamber at a second pressure that is also low, the solvent contained in the first liquid in the first chamber is transferred to the second liquid in the second chamber through the hollow fiber membrane, The concentrated liquid which is the concentrated first liquid is discharged from the first chamber, and the diluted liquid which is the diluted second liquid is discharged from the second chamber,
前記中空糸膜の外側の空間が前記第 1室であり、 前記中空糸膜の内 側の空間が前記第 2室であり、 The outer space of the hollow fiber membrane is the first chamber, the inner space of the hollow fiber membrane is the second chamber,
前記第 1液と前記第 2液の浸透圧差が 4 IV! 3以下である、 膜分離 方法。 The membrane separation method, wherein the osmotic pressure difference between the first liquid and the second liquid is 4 IV! 3 or less.
PCT/JP2020/007080 2019-02-28 2020-02-21 Hollow fiber membrane, hollow fiber membrane production method, hollow fiber membrane module, membrane separator, and membrane separation method WO2020175375A1 (en)

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