Summary of the invention
The present invention provides a kind of two-stage coagulation of the PVC of being used for acidic and alkaline waste water to handle and the biological treatment process combined, has improved inorganic substance and organic clearance in the PVC acidic and alkaline waste water.
A kind of PVC acidic and alkaline waste water two-stage coagulation and biological synergetic treatment process comprise the steps:
(1) two-stage coagulation is handled:
First step coagulating treatment:
In pending PVC acidic and alkaline waste water, add alkali lye, the pH value of regulating the PVC acidic and alkaline waste water adds 0.3%~1.2% coagulating agent FeSO to 9-10
4With 0.01%~0.03% coagulant aids PAM (SEPIGEL 305, Polyacrylamide).
Second stage coagulating treatment: in through the PVC acidic and alkaline waste water after the first step coagulating treatment, add alkali lye; Regulate PVC acidic and alkaline waste water pH value to 10-11; Add 0.3%~0.6% coagulating agent PAC (Poly aluminum Chloride (PAC); Polyaluminium Chloride) and 0.01%~0.03% coagulant aids HCA (positively charged ion coagulant aids-polymerization dimethyl diallyl ammonium chloride) or PAM, the organic monomer that under low pH, is difficult to remove is separated out from the PVC acidic and alkaline waste water;
Wherein said coagulating agent, coagulant aids all are to be benchmark with pending PVC acidic and alkaline waste water total mass, add by mass percentage.
Described alkali lye is generally adopted the chemical plant waste lye NaOH that concentration is 2~10g/L, or mass percent concentration is 3~8% liming alkali lye.
First step coagulating treatment can according to circumstances be filtered after accomplishing, and filtrating (through the PVC acidic and alkaline waste water after the first step coagulating treatment) gets into second stage coagulating treatment then.
(2) biological treatment:
The PVC acidic and alkaline waste water that will pass through the two-stage coagulation processing carries out first step biological treatment and second stage biological treatment successively; Carry out the PVC acidic and alkaline waste water discharging after solid-liquid separation will be handled then.
Can filter based on situation after two-stage coagulation is finished dealing with, filtrating (through the PVC acidic and alkaline waste water of two-stage coagulation processing) gets into biological treatment then.
The first step biological treatment work period is 3 hours;
The second stage biological treatment work period is 5 hours, and wherein water inlet (aeration) is 2.5 hours, and solid-liquid separation 2 hours precipitates 0.5 hour.
Wherein said first step biological treatment is to utilize active sludge that waste water is handled.
The biological treatment of the described second stage is to utilize swimming biofilm packing and active sludge that waste water is handled.As preferably, utilize aerated conduit to carry out aeration during the biological treatment of the described second stage.
Described swimming biofilm packing can adopt the commercially available prod, the Biofringe biologic packing material (BF) that for example adopts Japanese NET Co., Ltd. to provide, long 520mm, D 100mm, specific surface area 3410m
2/ m
3, constitute by acrylic fibers, be the radioactivity linear structure.
After carrying out described solid-liquid separation, the PVC acidic and alkaline waste water after obtaining mud and handling, and this mud still has certain activity, as preferably, is back to first step biological treatment stage to major general's part mud and reuses.
In the biological treatment process of step (2), adopt biological treatment tank; As preferably; The biological treatment tank that the present invention adopts is by the annular internal partition wall and be in the outer partition wall of its peripheral annular and surround; Wherein internal partition wall institute area surrounded is inner biotic district, and the zone between outer partition wall and the internal partition wall is the outside biotic district of annular.
Be full of active sludge in the inner biotic district, be used for described first step biological treatment, dividing plate is stamped at top, inner biotic district, and the dividing plate that sewage water inlet pipe passes the top gets in the inner biotic district, and extends to bottom, inner biotic district.
In the outside biotic district swimming biofilm packing and active sludge are housed, are used for the biological treatment of the described second stage, the bottom in the outside biotic district is provided with aerated conduit.
The internal partition wall top is provided with water outlet, when inner biotic district liquid level reaches this water outlet, and can be through water outlet overflow to outside biotic district.Internal partition wall bottom is provided with flashboard, is communicated with in inner biotic district and the outside biotic district when flashboard is opened.
In the outside biotic district of annular, mark off the subregion, be used to carry out described solid-liquid separation, but be open between settling section and the outside biotic district, be provided with the honeycomb inclined-tube filler in the settling section, can improve processing power and speed as settling section.
The outer partition wall top adjacent with settling section is provided with water outlet, when the waste water liquid level after the processing in the outer settling section reaches this water outlet, discharges biological treatment tank through water outlet.
The outer partition wall top base adjacent with settling section is provided with mud return line; Mud return line is drawn biological treatment tank from the bottom of settling section; Lead to inner biotic district then, the top, biotic district extend in the inner biotic district internally, and extends to bottom, inner biotic district.
During biological treatment tank work; The PVC acidic and alkaline waste water of handling through two-stage coagulation gets into the inner biotic district from the top through sewage water inlet pipe; Water outlet through the internal partition wall top after finishing dealing with drains in the outside biotic district; Progress into settling section after externally finishing dealing with in the biotic district and carry out sedimentation, and the waste water that is in after the processing on upper strata is discharged biological treatment tank through the water outlet at outer partition wall top, a mud part that is in lower floor is passed through mud return line; Row reuses in inner biotic district, and a part is discarded through the branch road discharging of mud return line.
Inner biotic district utilizes top spacer to seal, and forms the anaerobic zone in the treating processes, the open setting in outside biotic district, and a large amount of aeration, and when flowing out outward, along with the increase of dissolved oxygen content, the experience anoxic has arrived oxygen condition to waste water by interior.
Certainly, for the whole process that realizes carrying out a biological disposal upon, biological treatment tank also can other forms of the prior art.
The invention solves in the past the problem that self no solid-liquid separation and inner mud reflux, increased the possibility of the independent utility of single assembly, reduced and taken up an area of and investment, reduced running cost.Owing in a device, just can solve the problem that mud refluxes, also can obtain simultaneously comparatively accurately and the control that is more prone to, make treatment effect more stable.
The present invention has adopted the swimming biofilm packing, bigger increase living weight, and make biology have more activity, biota is also more rich and varied.
There is a certain distance in the present invention to the application of the dirty waste water of different quality; Be particularly suitable for the processing of the trade effluent of difficult for biological degradation; Generally can improve processing efficiency 18%~30%; Than not with the device of solid-liquid separation and internal reflux, can reduce working cost 5%~13%, reduce investment 8%~12%; And treatment effect is stable more and reliable, easy to operate, safeguards simple.
The present invention is used for the obvious processing effect of PVC acidic and alkaline waste water, can effectively reduce investment and processing costs, and removal effect is stable, especially better to the processing of hard-degraded substance in the waste water.Compare with uniprocessing, can improve processing efficiency 20%~27%, reduce processing costs 12%.‘
Embodiment
Embodiment 1
Produce to certain that to add mass percent concentration in the PVC acidic and alkaline waste water in the chemical enterprise of PVC be that the pH value scope that 6% liming alkali lye is regulated waste water is 9-10, and add 0.6% coagulating agent FeSO
4With 0.03% coagulant aids PAM;
Carry out second stage coagulating treatment then: add mass percent concentration once more and be 6% liming alkali lye and regulate waste water ph to 10-11; And add 0.4% coagulating agent PAC and 0.02% coagulant aids HCA (positively charged ion coagulant aids), the organic monomer that under low pH, is difficult to remove is separated out from waste water.
Wherein coagulating agent, coagulant aids all are to be benchmark with pending PVC acidic and alkaline waste water total mass, add by mass percentage.
The PVC acidic and alkaline waste water that will pass through the two-stage coagulation processing enters the biotic district, inside of annular biological treatment tank, utilizes active sludge to carry out first step biological treatment, and its work period is 4 hours; Enter after the processing and be in the outside biotic district of the peripheral annular in inner biotic district; Utilize swimming biofilm packing and active sludge to carry out second stage biological treatment; Its work period is 4 hours (water inlet, an aeration 2.5 hours, solid-liquid separation 2 hours precipitates 0.5 hour); Get into settling section in the outside biotic district at last; Under the honeycomb inclined-tube effect, carry out solid-liquid separation, the PVC acidic and alkaline waste water after isolated liquid phase is promptly handled through detect up to standard after discharging, isolated solid phase sludge is partly refluxed to first step biological treatment stage recycling.
The present invention utilizes two biotic active sludge and microbial film associated treatment; Get into settling section again and carry out solid-liquid separation; Can give full play to the removal effect of biological flocculation adsorption to particulate state and colloidal material; Reach at short notice and to realize removing the purpose that mainly contains organic pollutants and total phosphorus, total nitrogen, and sludge yield is few, running cost and investment cost are all lower.
Inner biotic district utilizes top spacer to seal, and forms the anaerobic zone in the treating processes, the open setting in outside biotic district, and a large amount of aeration, and when flowing out outward, along with the increase of dissolved oxygen content, the experience anoxic has arrived oxygen condition to waste water by interior.
Handle and biological treatment through two-stage coagulation, PVC acidic and alkaline waste water index changes as follows:
PVC acidic and alkaline waste water before handling: COD 600mg/L; BOD
5200mg/L; SS 200mg/L; Total hardness 3000mg/L; Total alkalinity 750mg/L; Colourity 30;
PVC acidic and alkaline waste water after the processing: COD 60mg/L; BOD
510mg/L; SS 200mg/L; Total hardness 450mg/L; Total alkalinity 350mg/L; Colourity 15.
Embodiment 2
Adding mass percent concentration in the dyeing waste water in certain printing and dyeing enterprise and be 4% liming alkali lye, to regulate the pH value scope of waste water be 8-9, and add 0.6% coagulating agent FeSO
4With 0.03% coagulant aids PAM;
Carry out second stage coagulating treatment then: add mass percent concentration once more and be 6% liming alkali lye and regulate waste water ph to 10-11; And add 0.4% coagulating agent PAC and 0.02% coagulant aids HCA (positively charged ion coagulant aids), the organic monomer that under low pH, is difficult to remove is separated out from waste water.
Wherein coagulating agent, coagulant aids all are to be benchmark with pending PVC acidic and alkaline waste water total mass, add by mass percentage.
Dyeing waste water gets into annular biological treatment tank through coagulating treatment and carries out the biological synergetic processing, at first gets into inner biotic district, utilizes active sludge to carry out first step biological treatment, and its work period is 3 hours; Enter after the processing and be in the outside biotic district of the peripheral annular in inner biotic district; Utilize swimming biofilm packing and active sludge to carry out second stage biological treatment; Its work period is 5 hours (water inlet, an aeration 2.5 hours, solid-liquid separation 2 hours precipitates 0.5 hour); Get into settling section in the outside biotic district at last; Under the honeycomb inclined-tube effect, carry out solid-liquid separation, the waste water after isolated liquid phase is promptly handled through detect up to standard after discharging, isolated solid phase sludge is partly refluxed to first step biological treatment stage recycling.
Handle and biological treatment through two-stage coagulation, the waste water index changes as follows:
Waste water before handling: COD 100mg/L; BOD525mg/L; SS 70mg/L; PH 6~9; Colourity 40;
Waste water after the processing: COD 25mg/L; BOD510mg/L; SS 8mg/L; PH 6.5~8.5; Colourity 15.