CN116253468A - Photocatalytic oxidation film system applied to sewage treatment and sewage treatment method - Google Patents
Photocatalytic oxidation film system applied to sewage treatment and sewage treatment method Download PDFInfo
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- 238000007254 oxidation reaction Methods 0.000 title claims abstract description 46
- 230000001699 photocatalysis Effects 0.000 title claims abstract description 46
- 239000010865 sewage Substances 0.000 title claims abstract description 44
- 230000003647 oxidation Effects 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000004062 sedimentation Methods 0.000 claims abstract description 50
- 239000012528 membrane Substances 0.000 claims abstract description 43
- 238000006243 chemical reaction Methods 0.000 claims abstract description 41
- 239000003054 catalyst Substances 0.000 claims abstract description 40
- 238000000926 separation method Methods 0.000 claims abstract description 36
- 239000011943 nanocatalyst Substances 0.000 claims abstract description 34
- 239000000919 ceramic Substances 0.000 claims abstract description 32
- 230000005484 gravity Effects 0.000 claims abstract description 32
- 230000003197 catalytic effect Effects 0.000 claims abstract description 16
- 238000001556 precipitation Methods 0.000 claims abstract description 14
- 238000005273 aeration Methods 0.000 claims abstract description 13
- 238000011084 recovery Methods 0.000 claims abstract description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 31
- ONDPHDOFVYQSGI-UHFFFAOYSA-N zinc nitrate Chemical compound [Zn+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ONDPHDOFVYQSGI-UHFFFAOYSA-N 0.000 claims description 18
- 238000003756 stirring Methods 0.000 claims description 13
- 239000007795 chemical reaction product Substances 0.000 claims description 12
- 239000002105 nanoparticle Substances 0.000 claims description 12
- 239000002351 wastewater Substances 0.000 claims description 11
- 238000007599 discharging Methods 0.000 claims description 10
- 239000010802 sludge Substances 0.000 claims description 10
- 230000000712 assembly Effects 0.000 claims description 8
- 238000000429 assembly Methods 0.000 claims description 8
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 6
- 239000008367 deionised water Substances 0.000 claims description 6
- 229910021641 deionized water Inorganic materials 0.000 claims description 6
- VKYKSIONXSXAKP-UHFFFAOYSA-N hexamethylenetetramine Chemical compound C1N(C2)CN3CN1CN2C3 VKYKSIONXSXAKP-UHFFFAOYSA-N 0.000 claims description 6
- 239000011259 mixed solution Substances 0.000 claims description 6
- 238000005192 partition Methods 0.000 claims description 6
- 230000029087 digestion Effects 0.000 claims description 5
- 230000001376 precipitating effect Effects 0.000 claims description 5
- 238000004064 recycling Methods 0.000 claims description 5
- 238000010992 reflux Methods 0.000 claims description 4
- 239000000243 solution Substances 0.000 claims description 4
- 238000010521 absorption reaction Methods 0.000 claims description 3
- 238000005119 centrifugation Methods 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 235000010299 hexamethylene tetramine Nutrition 0.000 claims description 3
- 239000004312 hexamethylene tetramine Substances 0.000 claims description 3
- 239000002244 precipitate Substances 0.000 claims description 3
- 238000001179 sorption measurement Methods 0.000 claims description 3
- 238000002156 mixing Methods 0.000 claims description 2
- 238000007146 photocatalysis Methods 0.000 abstract description 6
- 238000005516 engineering process Methods 0.000 abstract description 5
- 239000003344 environmental pollutant Substances 0.000 abstract description 3
- 231100000719 pollutant Toxicity 0.000 abstract description 3
- 238000013032 photocatalytic reaction Methods 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- 229910010413 TiO 2 Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000011941 photocatalyst Substances 0.000 description 2
- 238000002834 transmittance Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
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- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D21/00—Separation of suspended solid particles from liquids by sedimentation
- B01D21/02—Settling tanks with single outlets for the separated liquid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
- B01D63/08—Flat membrane modules
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/30—Treatment of water, waste water, or sewage by irradiation
- C02F1/32—Treatment of water, waste water, or sewage by irradiation with ultraviolet light
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/72—Treatment of water, waste water, or sewage by oxidation
- C02F1/725—Treatment of water, waste water, or sewage by oxidation by catalytic oxidation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F7/00—Aeration of stretches of water
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F2001/007—Processes including a sedimentation step
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/10—Inorganic compounds
- C02F2101/16—Nitrogen compounds, e.g. ammonia
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/08—Chemical Oxygen Demand [COD]; Biological Oxygen Demand [BOD]
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2209/00—Controlling or monitoring parameters in water treatment
- C02F2209/14—NH3-N
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/30—Wastewater or sewage treatment systems using renewable energies
- Y02W10/37—Wastewater or sewage treatment systems using renewable energies using solar energy
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Abstract
The invention provides a photocatalytic oxidation film system applied to sewage treatment, which comprises a photocatalytic oxidation reaction unit and a gravity precipitation unit; the photocatalysis reaction unit comprises a reaction tank, a ZnO nano catalyst, an ultraviolet light source, an aeration pipeline and a stirrer, wherein the ZnO nano catalyst, the ultraviolet light source, the aeration pipeline and the stirrer are arranged in the reaction tank; the gravity sedimentation unit comprises a sedimentation tank and a separation component arranged in the sedimentation tank; the separation components are transversely arranged in the sedimentation tank to divide the sedimentation tank into a plurality of separation areas, gaps are reserved between the bottoms of the separation components and the sedimentation tank, and the tops of the separation components fall in a step shape; meanwhile, each separation assembly further comprises a group of flat ceramic membranes which are longitudinally arranged, the flat ceramic membranes are connected into a mechanical vibration facility, and UVC lamps are arranged among the flat ceramic membranes. The invention also provides a sewage treatment method. The invention meets the engineering application conditions of the photocatalysis technology in sewage treatment and has the advantages of high catalytic efficiency, good catalyst recovery rate, high pollutant removal efficiency and the like.
Description
Technical Field
The invention relates to the technical field of photocatalysis, in particular to a photocatalysis oxidation film system applied to sewage treatment and a sewage treatment method.
Background
The technology of purifying air by using the photocatalyst is mature gradually abroad, but the application of the photocatalyst in water treatment is still a starting stage. The process is a low-temperature deep reaction, and has the characteristics of thorough purification, green energy, strong oxidability and the like.
At present, the domestic and foreign photocatalytic oxidation technology is a few distances away from the practical sewage treatment application, and mainly has the following technical problems: (1) Traditional TiO 2 The ultraviolet light absorption range of the catalyst is narrow, and the light energy utilization rate is lowThe method comprises the steps of carrying out a first treatment on the surface of the The problem of transmittance, especially the poorer transmittance of ultraviolet light with short wavelength, can affect the photocatalysis effect; (2) The catalytic effect of the curing catalyst is very unstable and easy to deactivate, while the suspension catalyst is mostly nano particles (the catalytic effect is not good when the catalyst is too large), and the recovery is difficult.
Therefore, on one hand, from the catalyst material, new catalyst materials are researched and developed as catalysts, so that the catalytic efficiency can be effectively ensured; on the other hand, a stable membrane process structure suitable for recycling the catalyst is explored, and the stability and the application possibility of the process are further improved.
Disclosure of Invention
The invention aims to solve the technical problems of low catalytic efficiency, unstable catalytic performance, difficult catalyst recovery and the like caused by adopting the existing catalyst and process for sewage treatment.
The invention adopts the following technical scheme to solve the technical problems:
a photocatalytic oxidation film system for sewage treatment, comprising:
the photocatalytic oxidation reaction unit is used for photocatalytic oxidation treatment of wastewater and comprises a reaction tank, and a ZnO nano catalyst, an ultraviolet light source, an aeration pipeline and a stirrer which are arranged in the reaction tank;
the gravity sedimentation unit is used for recycling and discharging the ZnO nano catalyst and comprises a sedimentation tank and a plurality of separation components arranged in the sedimentation tank; the separation assemblies are transversely arranged in the sedimentation tank, the sedimentation tank is divided into a plurality of separation areas, gaps are reserved between the bottoms of the separation assemblies and the sedimentation tank, and the tops of the separation assemblies drop in a step shape; simultaneously, every the subassembly still includes a set of dull and stereotyped ceramic membrane of vertical arrangement respectively, and every dull and stereotyped ceramic membrane inserts mechanical vibration facility respectively, arranges a set of UVC lamp respectively between the dull and stereotyped ceramic membrane of same group.
As a preferred embodiment of the present invention, in the photocatalytic oxidation reaction unit: the ZnO nano catalyst is specifically ZnO nano particles, has a double-section rod-shaped structure, has the diameter of 100nm and has the strongest absorption peak of 388nm in the ultraviolet region; the adding concentration of ZnO nano particles is 0.5-2 g/L, and the pH value of the reaction tank is 5.2-6.6 after the ZnO nano catalyst is added.
As one of the preferred modes of the present invention, the ZnO nanoparticle is prepared by a microwave method: zinc nitrate is dissolved in deionized water to prepare zinc nitrate aqueous solution; dripping hexamethylenetetramine with the concentration of 0.8M into the zinc nitrate aqueous solution, and stirring at the stirring speed of 100-300 r/min; then, the mixed solution is moved into a microwave reactor, and after microwave reaction for 1h, the mixed solution is taken out and naturally cooled to room temperature; finally, the precipitate was separated from the solution by centrifugation, washed several times with deionized water and ethanol, and dried in a drying chamber.
As a preferred embodiment of the present invention, in the photocatalytic oxidation reaction unit: the aeration pipeline is arranged at the bottom of the reaction tank and is used for preventing the ZnO nano catalyst from precipitating; the stirrer extends downwards into the reaction tank along the top of the reaction tank and is used for stirring the wastewater and the ZnO nano catalyst for mixing; the ultraviolet light source is arranged around the stirrer and used for emitting ultraviolet light.
As one of the preferable modes of the invention, the water inlet of the gravity sedimentation unit is connected with the water outlet of the photocatalytic oxidation reaction unit so as to receive the reaction product after being treated by the photocatalytic oxidation reaction unit.
As one of preferable modes of the invention, in the gravity settling unit: the separation components are arranged at equal intervals, the distance between the bottoms of the separation components and the bottom of the pool is not less than 30cm, the heights are sequentially 1/3, 1/5 and 1/10 of the depth of the pool, and the stage recovery and the classified mud discharge of the ZnO nano catalyst are completed by utilizing gravity.
As one of preferable modes of the invention, in the gravity settling unit: the dimension length-to-height ratio of each flat ceramic membrane of the separation assembly is (1.5-2): 1, the space between the flat ceramic membranes in the same group is 14cm, and a UVC lamp is inserted in the middle; the distance between the UVC lamps and the surface of the corresponding flat ceramic film is 10-30 cm, and the distance between the UVC lamps is not less than 30cm; meanwhile, the vibration frequency of the mechanical vibration facilities connected with the flat ceramic membranes is 60-600 times/min, the vibration force of each square meter of membrane is 10-200N, the connection power supply voltage is 220V, and the current is 0-20A.
As one of the preferable modes of the invention, each area of the separated sedimentation tank is also respectively connected with a catalyst return pipeline and a sludge discharge pipeline; the tail end of the catalyst return pipeline is connected with the reaction tank, and the tail end of the sludge discharge pipeline is connected with the outside of the system.
A method for sewage treatment by utilizing a photocatalytic oxidation film system adopts the photocatalytic oxidation film system applied to sewage treatment, and comprises the following specific steps:
(1) The sewage is sent into a reaction tank of a photocatalytic oxidation reaction unit, the sewage and the ZnO nano catalyst are fully mixed by stirring of a stirrer, and the ZnO nano catalyst carries out catalytic oxidation reaction on the sewage under the action of an ultraviolet light source; during the period, the aeration pipeline prevents the catalyst from precipitating and simultaneously optimizes the catalytic effect; the reaction product is communicated with the water inlet of the gravity sedimentation unit through the water outlet and flows into the gravity sedimentation unit;
(2) The gravity sedimentation unit adopts a step gravity sedimentation mode; the ZnO nano catalyst in the reaction product is separated and precipitated under the action of each group of flat ceramic membranes, and flows back to the reaction tank through a catalyst return pipeline; simultaneously, wastewater in the reaction product is discharged through a water outlet of the gravity precipitation unit; during the period, a UVC lamp between the flat ceramic membranes is connected, so that the sewage treatment efficiency is accelerated, and the adsorption precipitation on the surfaces of the digestion membranes is accelerated; simultaneously, a mechanical vibration facility is started at regular time to remove the catalyst layer attached to the surface of the membrane;
(3) And (3) discharging mud from a rearmost separation area of the sedimentation tank at regular intervals, and discharging mud through a mud discharge pipeline after a mud discharge valve is opened.
In the step (2), the reflux ratio of the catalyst in each separation area of the sedimentation tank is 5-10%; starting a mechanical vibration facility for 5min every 12h, and removing the catalyst layer attached to the surface of the membrane; in the step (3), mud is discharged from a separation area at the rearmost part of the sedimentation tank at intervals of 5 d.
Compared with the prior art, the invention has the advantages that:
(1) The invention adopts ZnO nano particles as a suspension catalyst, can effectively complete the catalytic oxidation process of sewage under ultraviolet irradiation, and effectively avoids the adoption of traditional TiO 2 And the problems of low light energy utilization rate, low catalytic efficiency and unstable catalytic performance caused by the curing catalyst;
(2) Aiming at the problem of difficult recovery of the suspension type catalyst, the invention designs a stable membrane process structure for recycling the catalyst, and further improves the process stability and the application possibility through membrane pollution control (aeration, pollutant digestion and separation equipment structure); the process has the advantages of high catalyst recycling rate, effective control of membrane pollution, low overall investment and running cost of the system, and high engineering application value and environmental protection value;
(3) Aiming at the condition that the surface of a flat ceramic membrane is easy to be blocked by a catalyst in the running process of the system, the invention adopts a combined operation mode of periodic mechanical vibration and digestion by a UVC lamp, thereby effectively relieving the membrane pollution condition and ensuring the long-time stable running of the system;
(4) The invention satisfies engineering application conditions of photocatalysis technology in sewage treatment, can realize new breakthrough of the technology in engineering application in the field of water treatment, and has the advantages of high pollutant removal efficiency, less dosage, small occupied area, stable effluent quality and less mud yield.
Drawings
FIG. 1 is a schematic diagram showing the front view of the photocatalytic oxidation film system applied to sewage treatment in example 1 (in the figure, the arrow indicates the direction of flow of sewage/catalyst/sludge);
fig. 2 is a schematic side view of the partition assembly of fig. 1.
In the figure: 1 is a photocatalytic oxidation reaction unit, 11 is a reaction tank, 111 is a first water inlet, 112 is a backflow port, 113 is a first water outlet, 12 is a ZnO nano catalyst, 13 is an ultraviolet light source, 14 is an aeration pipeline, 15 is a stirrer, 2 is a gravity sedimentation unit, 21 is a sedimentation tank, 211 is a second water inlet, 212 is a second water outlet, 22 is a separation component, 221 is a flat ceramic membrane, 23 is a mechanical vibration facility, 24 is a UVC lamp, 25 is a catalyst backflow pipeline, 251 is a backflow control valve, 26 is a mud discharge pipeline, 261 is a mud discharge valve.
Detailed Description
The following describes in detail the examples of the present invention, which are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific operation procedures are given, but the scope of protection of the present invention is not limited to the following examples.
Example 1
As shown in fig. 1 to 2, a photocatalytic oxidation film system for sewage treatment according to the present embodiment includes a photocatalytic oxidation reaction unit 1 and a gravity precipitation unit 2.
The photocatalytic reaction unit 1 is used for photocatalytic oxidation treatment of wastewater and comprises a reaction tank 11, and a ZnO nano catalyst 12, an ultraviolet light source 13, an aeration pipeline 14 and a stirrer 15 which are arranged in the reaction tank 11. Wherein, the size of the reaction tank 11 is 4.2m×4cm×2m, one end of the reaction tank 11 is provided with a first water inlet 111 and a reflux port 112, and the other end is provided with a first water outlet 113. The ZnO nano-catalyst 12 is contained in the reaction tank 11. The aeration pipeline 14 is arranged at the bottom of the reaction tank 11 and is used for preventing the ZnO nano-catalyst 12 from precipitating. A stirrer 15 extends down along the top of the reaction tank 11 into the reaction tank 11 for stirring the wastewater and the ZnO nanocatalyst 12 to mix. The ultraviolet light source 13 is disposed around the stirrer 15 and is used for emitting ultraviolet light.
The gravity precipitation unit 2 utilizes gravity to complete the stage recovery of the ZnO nano-catalyst 12, and comprises a precipitation tank 21 and three separation components 22 arranged in the precipitation tank 21. Wherein, the size of the sedimentation tank 21 is 8m×4cm×1.8mm, one end of the sedimentation tank 21 is provided with a second water inlet 211, which is connected with a first water outlet 113 of the reaction tank 11 and is used for receiving reaction products (including reaction wastewater, znO nano catalyst 12 and mud) from the photocatalytic reaction unit 1, and the other end of the sedimentation tank 21 is provided with a second water outlet 212 for discharging wastewater treated by the unit. The separation assemblies 22 are arranged in the sedimentation tank 21 at equal intervals along the transverse direction thereof, the sedimentation tank 22 is divided into four separation areas, gaps are reserved between the bottom of each separation assembly 22 and the sedimentation tank 21, and the tops of the separation assemblies 22 drop in a step shape. Meanwhile, each partition assembly 22 further comprises a group of flat ceramic membranes 221 which are longitudinally and equidistantly arranged, each flat ceramic membrane 221 is respectively connected to the mechanical vibration facility 23, and a group of UVC lamps 24 are respectively arranged between the same group of flat ceramic membranes 221.
In addition, each region of the separated sedimentation tank 21 is further connected to a catalyst return pipe 25 and a sludge discharge pipe 26, the catalyst return pipe 25 is provided with a return control valve 251, and the sludge discharge pipe 26 is provided with a sludge discharge valve 261. Wherein, the tail end of the catalyst return pipe 25 is connected with a return port 112 of the reaction tank 11 to return the recovered ZnO nano catalyst to the reaction tank 11 again; the sludge discharge pipe 26 is connected at its end outside the system for discharging sludge periodically outwards.
Further, in the photocatalytic reaction unit 1 of the present embodiment:
the ZnO nano catalyst 12 is ZnO nano particles, has a double-section rod-shaped structure, has the diameter of 100nm and has the strongest absorption peak of 388nm in the ultraviolet region. The adding concentration of the ZnO nano-particles is 0.5-2 g/L, and the pH of the reaction tank is 5.2-6.6 after the ZnO nano-particles are added.
The ZnO nano-particles are prepared by a microwave method, and the specific method is as follows:
zinc nitrate is dissolved in deionized water to prepare zinc nitrate aqueous solution; dripping hexamethylenetetramine with the concentration of 0.8M into the zinc nitrate aqueous solution, and stirring at the stirring speed of 100-300 r/min; then, the mixed solution is moved into a microwave reactor, and after microwave reaction for 1h, the mixed solution is taken out and naturally cooled to room temperature; finally, the precipitate was separated from the solution by centrifugation, washed several times with deionized water and ethanol, and dried in a drying chamber.
The stirrer 15 was a 3kW stirrer, and the stirring speed was set to 80r/min.
Further, in the gravity settling unit 2 of the present embodiment:
in order to more efficiently realize the separation and precipitation of the catalyst particles, the bottom of each separation component 22 is not less than 30cm, preferably 30cm, from the bottom of the sedimentation tank 21, and the heights are sequentially 1/3, 1/5 and 1/10 of the depth of the tank body. Wherein each partition assembly 22 is suspended by a frame (not shown) to a corresponding height.
Meanwhile, the length to height ratio of each flat ceramic film 221 of the partition member 22 is (1.5 to 2): 1, preferably 2:1; the space between the flat ceramic membranes 221 in the same group is 14cm, and a UVC lamp 24 is inserted in the middle; the UVC lamps 24 are spaced 10-30 cm, preferably 20cm, from the surface of the corresponding flat ceramic film 221; the spacing between UVC lamps 24 is not less than 30cm, preferably 25cm; meanwhile, the mechanical vibration facility 23 to which each flat ceramic membrane 221 is connected has a vibration frequency of 60 to 600 times/min, preferably 80 times/min; the vibration force of the film per square meter is 10-200N, preferably 100N, the connection power voltage is 220V, and the current is 0-20A, preferably 10A.
Example 2
The method for sewage treatment by using the photocatalytic oxidation film system in the embodiment adopts the photocatalytic oxidation film system in the embodiment 1, and comprises the following specific steps:
(1) The sewage is sent into a reaction tank 11 of a photocatalytic oxidation reaction unit 1, the sewage is fully mixed with a ZnO nano catalyst 12 through the stirring of a stirrer 15, and the ZnO nano catalyst 12 carries out catalytic oxidation reaction on the sewage under the action of an ultraviolet light source 13; during this period, the aeration line 14 prevents catalyst precipitation while optimizing the catalytic effect; the reaction product is communicated with the second water inlet 211 of the gravity sedimentation unit 2 through the first water outlet 113 and flows into the gravity sedimentation unit 2;
(2) The gravity sedimentation unit 2 adopts a step gravity sedimentation mode; the ZnO nano catalyst 12 in the reaction product is separated and precipitated under the action of each group of flat ceramic membranes 221, and flows back to the reaction tank 11 through the catalyst return pipeline 25, wherein the reflux ratio is 5-10%; simultaneously, the wastewater in the reaction product is discharged through the second water outlet 212 of the gravity precipitation unit 2; during the period, the UVC lamp 24 between the flat ceramic membranes 221 is turned on, so that the sewage treatment efficiency is accelerated, and the adsorption precipitation on the surfaces of the digestion membranes is accelerated; simultaneously, the mechanical vibration facility 23 is started to run for 5min at every 12h at regular time, and the catalyst layer attached to the surface of the membrane is removed;
(3) And (3) discharging mud from the rearmost partition zone of the sedimentation tank 21 for 20min at intervals of 5d, and discharging mud through a mud discharge pipeline 26 after the mud discharge valve 261 is opened.
Application example
Industrial wastewater treatment was performed using the system of example 1 and the method of example 2, and the results were as follows:
the average water quality parameters of the industrial sewage are detected as follows: COD is 630.50mg/L, BOD5 = 57.28mg/L, pH =6.44, SS is 178mg/L, chromaticity is 3209 times, NH 3- N is 126mg/L, and the inflow velocity is 10m 3 /h。
After the system stably operates for 6 hours, the removal rates of COD and chromaticity respectively reach 75% and 85%; BOD5 increased to 97.33mg/L and biodegradability was slightly improved. Meanwhile, the electricity consumption under the condition is calculated to be 15.21kw h/m 3 。
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, and alternatives falling within the spirit and principles of the invention.
Claims (10)
1. A photocatalytic oxidation film system for sewage treatment, comprising:
the photocatalytic oxidation reaction unit is used for photocatalytic oxidation treatment of wastewater and comprises a reaction tank, and a ZnO nano catalyst, an ultraviolet light source, an aeration pipeline and a stirrer which are arranged in the reaction tank;
the gravity sedimentation unit is used for recycling and discharging the ZnO nano catalyst and comprises a sedimentation tank and a plurality of separation components arranged in the sedimentation tank; the separation assemblies are transversely arranged in the sedimentation tank, the sedimentation tank is divided into a plurality of separation areas, gaps are reserved between the bottoms of the separation assemblies and the sedimentation tank, and the tops of the separation assemblies drop in a step shape; simultaneously, every the subassembly still includes a set of dull and stereotyped ceramic membrane of vertical arrangement respectively, and every dull and stereotyped ceramic membrane inserts mechanical vibration facility respectively, arranges a set of UVC lamp respectively between the dull and stereotyped ceramic membrane of same group.
2. The photocatalytic oxidation film system for sewage treatment according to claim 1, wherein, in the photocatalytic oxidation reaction unit: the ZnO nano catalyst is specifically ZnO nano particles, has a double-section rod-shaped structure, has the diameter of 100nm and has the strongest absorption peak of 388nm in the ultraviolet region; the adding concentration of ZnO nano particles is 0.5-2 g/L, and the pH value of the reaction tank is 5.2-6.6 after the ZnO nano catalyst is added.
3. The photocatalytic oxidation film system for sewage treatment according to claim 2, wherein the ZnO nanoparticles are prepared by a microwave method: zinc nitrate is dissolved in deionized water to prepare zinc nitrate aqueous solution; dripping hexamethylenetetramine with the concentration of 0.8M into the zinc nitrate aqueous solution, and stirring at the stirring speed of 100-300 r/min; then, the mixed solution is moved into a microwave reactor, and after microwave reaction for 1h, the mixed solution is taken out and naturally cooled to room temperature; finally, the precipitate was separated from the solution by centrifugation, washed several times with deionized water and ethanol, and dried in a drying chamber.
4. The photocatalytic oxidation film system for sewage treatment according to claim 1, wherein, in the photocatalytic oxidation reaction unit: the aeration pipeline is arranged at the bottom of the reaction tank and is used for preventing the ZnO nano catalyst from precipitating; the stirrer extends downwards into the reaction tank along the top of the reaction tank and is used for stirring the wastewater and the ZnO nano catalyst for mixing; the ultraviolet light source is arranged around the stirrer and used for emitting ultraviolet light.
5. The photocatalytic oxidation film system for sewage treatment according to claim 1, wherein the water inlet of the gravity precipitation unit is connected to the water outlet of the photocatalytic oxidation reaction unit to receive the reaction product from the light after the catalytic oxidation reaction unit.
6. The photocatalytic oxidation film system for sewage treatment according to claim 1, wherein, in the gravity settling unit: the separation components are arranged at equal intervals, the distance between the bottoms of the separation components and the bottom of the pool is not less than 30cm, the heights are sequentially 1/3, 1/5 and 1/10 of the depth of the pool, and the stage recovery and the classified mud discharge of the ZnO nano catalyst are completed by utilizing gravity.
7. The photocatalytic oxidation film system for sewage treatment according to claim 1, wherein, in the gravity settling unit: the dimension length-to-height ratio of each flat ceramic membrane of the separation assembly is (1.5-2): 1, the space between the flat ceramic membranes in the same group is 14cm, and a UVC lamp is inserted in the middle; the distance between the UVC lamps and the surface of the corresponding flat ceramic film is 10-30 cm, and the distance between the UVC lamps is not less than 30cm; meanwhile, the vibration frequency of the mechanical vibration facilities connected with the flat ceramic membranes is 60-600 times/min, the vibration force of each square meter of membrane is 10-200N, the connection power supply voltage is 220V, and the current is 0-20A.
8. The photocatalytic oxidation film system for sewage treatment according to any one of claims 1 to 7, characterized in that each area of the separated sedimentation tank is further connected with a catalyst return pipe and a sludge discharge pipe, respectively; the tail end of the catalyst return pipeline is connected with the reaction tank, and the tail end of the sludge discharge pipeline is connected with the outside of the system.
9. A method for sewage treatment by using a photocatalytic oxidation film system, characterized in that the photocatalytic oxidation film system applied to sewage treatment according to any one of claims 1 to 8 is adopted; the method comprises the following specific steps:
(1) The sewage is sent into a reaction tank of a photocatalytic oxidation reaction unit, the sewage and the ZnO nano catalyst are fully mixed by stirring of a stirrer, and the ZnO nano catalyst carries out catalytic oxidation reaction on the sewage under the action of an ultraviolet light source; during the period, the aeration pipeline prevents the catalyst from precipitating and simultaneously optimizes the catalytic effect; the reaction product is communicated with the water inlet of the gravity sedimentation unit through the water outlet and flows into the gravity sedimentation unit;
(2) The gravity sedimentation unit adopts a step gravity sedimentation mode; the ZnO nano catalyst in the reaction product is separated and precipitated under the action of each group of flat ceramic membranes, and flows back to the reaction tank through a catalyst return pipeline; simultaneously, wastewater in the reaction product is discharged through a water outlet of the gravity precipitation unit; during the period, a UVC lamp between the flat ceramic membranes is connected, so that the sewage treatment efficiency is accelerated, and the adsorption precipitation on the surfaces of the digestion membranes is accelerated; simultaneously, a mechanical vibration facility is started at regular time to remove the catalyst layer attached to the surface of the membrane;
(3) And (3) discharging mud from a rearmost separation area of the sedimentation tank at regular intervals, and discharging mud through a mud discharge pipeline after a mud discharge valve is opened.
10. The method for sewage treatment by using a photocatalytic oxidation film system according to claim 9, wherein in the step (2), the catalyst reflux ratio of each partition area of the sedimentation tank is 5% -10%; starting a mechanical vibration facility for 5min every 12h, and removing the catalyst layer attached to the surface of the membrane; in the step (3), mud is discharged from a separation area at the rearmost part of the sedimentation tank at intervals of 5 d.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102260046A (en) * | 2010-05-28 | 2011-11-30 | 中国科学院大连化学物理研究所 | Microwave synthesis method of zinc oxide film with oriented nanorod structure |
| CN206447734U (en) * | 2017-01-17 | 2017-08-29 | 杭州华测检测技术有限公司 | A kind of combined type sewage treatment equipment |
| CN206680241U (en) * | 2017-04-06 | 2017-11-28 | 九江学院 | A kind of device that waste water is handled using photocatalysis membrana isolation technics |
| CN112624510A (en) * | 2020-12-23 | 2021-04-09 | 天津高能时代水处理科技有限公司 | Sewage advanced treatment combined device and process |
| CN214142021U (en) * | 2020-11-26 | 2021-09-07 | 成都瑞众合城环境治理有限公司 | Sewage treatment device |
| CN114229987A (en) * | 2021-12-20 | 2022-03-25 | 北京化工大学 | Flat ceramic membrane catalytic oxidation device and process for treating biologically-nondegradable wastewater |
-
2023
- 2023-03-01 CN CN202310206728.9A patent/CN116253468A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102260046A (en) * | 2010-05-28 | 2011-11-30 | 中国科学院大连化学物理研究所 | Microwave synthesis method of zinc oxide film with oriented nanorod structure |
| CN206447734U (en) * | 2017-01-17 | 2017-08-29 | 杭州华测检测技术有限公司 | A kind of combined type sewage treatment equipment |
| CN206680241U (en) * | 2017-04-06 | 2017-11-28 | 九江学院 | A kind of device that waste water is handled using photocatalysis membrana isolation technics |
| CN214142021U (en) * | 2020-11-26 | 2021-09-07 | 成都瑞众合城环境治理有限公司 | Sewage treatment device |
| CN112624510A (en) * | 2020-12-23 | 2021-04-09 | 天津高能时代水处理科技有限公司 | Sewage advanced treatment combined device and process |
| CN114229987A (en) * | 2021-12-20 | 2022-03-25 | 北京化工大学 | Flat ceramic membrane catalytic oxidation device and process for treating biologically-nondegradable wastewater |
Non-Patent Citations (4)
| Title |
|---|
| 宋华;翟小清;: "微波合成纳米氧化锌及其应用研究进展", 化学工业与工程技术, vol. 34, no. 06, 31 December 2013 (2013-12-31) * |
| 徐正伟等: "纳米科技探索——科普与实验（上册）", 30 June 2022, 苏州大学出版社, pages: 74 - 75 * |
| 汪大翚等: "水处理新技术及工程设计", 31 May 2001, 化学工业出版社, pages: 73 - 74 * |
| 王广丽: "纳米氧化锌的微观控制合成及光催化性功能研究", 中国优秀硕士学位论文全文数据库 工程科技 I辑, no. 2011, 15 September 2011 (2011-09-15), pages 020 - 164 * |
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