Background technology
polyvinyl chloride (PVC) is a kind of thermoplastic synthetic resin material in industry, agricultural and daily life that is widely used in.Because of its outstanding many character, the traditional material such as substituted metal gradually in a lot of fields, and the output of PVC is also soaring year by year.Industrial production polyvinyl chloride resin mainly contains acetylene method and calcium carbide route from source material classification; From technique classification, mainly contain suspension polymerization, emulsion polymerization, mass polymerization and solution polymerization process, wherein especially with suspension polymerization widespread use the most, the polyvinyl chloride resin of producing with the method in world wide accounts for 80% of ultimate production.Domestic polyvinyl chloride resin is produced and is mainly adopted the suspension polymerization based on calcium carbide.1 ton of PVC of the every production of this technique will produce 3 tons to 4 tons of centrifugal mother liquor waste waters.With Present Domestic PVC output, estimate, the annual production of PVC centrifugal mother liquor waste water is more than 2,500 ten thousand tons.PVC centrifugal mother liquor waste water not only output is very big, and contains the hardly degraded organic substances such as the dispersion agent that adds in technological process, terminator, and composition is more complicated, and intractability is large.On the other hand, such waste water COD is not high, and hardness and chlorion (Cl-) concentration is lower, reclaims potentiality larger.Shortage of water resources, pollution problem is the problem of jointly facing in world wide, this problem is especially serious at home.For chlorine industry Er Yan, industrial and mining enterprises, increasing waste water treatment process equipment, improve waste water circulation and use the trend place that has become industry development, is also the important guarantee of chlor-alkali industry Sustainable development.Current, most enterprises only do after simple process for rinse water for PVC centrifugal mother liquor waste water, after having Some Enterprises to attempt centrifugal mother liquor waste water to process for recirculated cooling water.Some patents have proposed the technique of PVC centrifugal mother liquor waste water degree of depth reuse, but there are many problems, as longer in the operational path proposing in the publication number Chinese patent literature that is 101333051, the aerobic residence time of two-stage anaerobic adds up 40 hours, and use activated sludge process and BAF technique for biochemical treatment simultaneously, on process goal, have overlapping, in addition, consider PVC mother liquid coming nature, adopt the two embrane methods of MF-RO can replace the ion exchange method that cost is higher completely; Although in the Chinese patent literature that is 102079604 such as publication number again, adopt inductive reaction device can avoid activated sludge process may problem in engineering, the problem includes: problems such as sludge bulkings, but inductive reaction device energy consumption applicable in the method is higher, in technique, continue to add multiple oxygenant further to aggravate the complicacy of blowdown composition.
Summary of the invention
the invention provides a kind of polyvinyl chloride centrifugation mother liquid waste water advanced treatment recovery method, overcome the deficiency of above-mentioned prior art, it can effectively solve, and current existing polyvinyl chloride centrifugation mother liquid waste water treatment process is consuming time, energy consumption is high, the unsettled problem of effect.
technical scheme of the present invention realizes by following measures: a kind of polyvinyl chloride centrifugation mother liquid waste water advanced treatment recovery method, carry out in the steps below: the first step, first polyvinyl chloride centrifugation mother liquid waste water is sent into and adjusted for No. one in pond, the temperature that regulates polyvinyl chloride centrifugation mother liquid waste water is that 30 ℃ to 35 ℃, PH are 8 to 9, phosphonium ion content is 1mg/L to 2mg/L; Second step, polyvinyl chloride centrifugation mother liquid waste water after regulating is sent in HBF one-level biological reaction tank, in temperature, be that 30 ℃ to 35 ℃, PH carry out organic preliminary decomposition under 8 to 9 conditions, the COD clearance that tentatively decomposes to polyvinyl chloride centrifugation mother liquid waste water reaches more than 40%, after preliminary decomposition, obtains once biochemical water; The 3rd step, will be once biochemical water send into and in hay tank, remove suspended contamination, then the once biochemical water after hay tank is processed is sent into and in surge tank, carried out further flocculation sediment, then the upper clear supernate in surge tank is sent in HBF two stage biological reactive tank, in temperature, be that 30 ℃ to 35 ℃, PH are under 8 to 9 conditions, to carry out organicly again decomposing, the COD again decomposing in solution is 40mg/L to 50mg/L, obtains for the biochemical water of common secondary clean, greening use after again decomposing.
the further optimization and/or improvements to foregoing invention technical scheme below:
above-mentioned the biochemical water of secondary is continued to be fed in adsorption tanks further to absorption polyvinyl alcohol and filters out after the impurity in solution, then obtaining reuse water up to standard after the secondary biochemistry water after adsorption tanks are processed is sequentially pumped into MF micro-filtration and RO reverse osmosis two-stage filtration.
above-mentionedly first the biochemical water of secondary is sent into and adjusted for No. two in ponds, after precipitating in No. two are adjusted pond, again clear liquid is continued to be fed in adsorption tanks, when needs carry out back washing to HBF two stage biological reactive tank, directly with the clear liquid in No. two adjustment ponds, HBF two stage biological reactive tank is carried out to back washing.
above-mentionedly with reuse water, the microfiltration membrane of MF micro-filtration is carried out to backwash.
above-mentioned HBF one-level biological reaction tank and HBF two stage biological reactive tank are fixed biologically membrane reactor.
in above-mentioned HBF one-level biological reaction tank, the particle size range of filler is that the particle size range of filler in 20mm to 35mm, HBF two stage biological reactive tank is 5mm to 15mm.
technical process of the present invention is simpler than traditional method, and hydraulic detention time is short, and energy consumption is low, and successful is stable, by the combination of biochemical method and multiple physical chemistry method, as the waste water advanced reuse technology of polyvinyl chloride centrifugation mother liquid, has certain feasibility and superiority.
Embodiment
the present invention is not subject to the restriction of following embodiment, can determine concrete embodiment according to technical scheme of the present invention and practical situation.
below in conjunction with embodiment, the invention will be further described:
embodiment 1, this polyvinyl chloride centrifugation mother liquid waste water advanced treatment recovery method carries out in the steps below: the first step, first polyvinyl chloride centrifugation mother liquid waste water is sent into and adjusted for No. one in pond, the temperature that regulates polyvinyl chloride centrifugation mother liquid waste water is that 30 ℃ to 35 ℃, PH are 8 to 9, phosphonium ion content is 1mg/L to 2mg/L; Second step, polyvinyl chloride centrifugation mother liquid waste water after regulating is sent in HBF one-level biological reaction tank, in temperature, be that 30 ℃ to 35 ℃, PH carry out organic preliminary decomposition under 8 to 9 conditions, the COD clearance that tentatively decomposes to polyvinyl chloride centrifugation mother liquid waste water reaches more than 40%, after preliminary decomposition, obtains once biochemical water; The 3rd step, will be once biochemical water send into and in hay tank, remove suspended contamination, then the once biochemical water after hay tank is processed is sent into and in surge tank, carried out further flocculation sediment, then the upper clear supernate in surge tank is sent in HBF two stage biological reactive tank, in temperature, be that 30 ℃ to 35 ℃, PH are under 8 to 9 conditions, to carry out organicly again decomposing, the COD again decomposing in solution is 40mg/L to 50mg/L, obtains for the biochemical water of common secondary clean, greening use after again decomposing.Hay tank is mainly used in filtering once the suspended substances such as bacterial classification that come off that contain in biochemical water, and hay tank need carry out timing backwash, washes away the impurity adhering to, and avoids affecting the follow-up effect that filters out; The hydraulic detention time of HBF one-level biological reaction tank and HBF two stage biological reactive tank is all about 3h, is far smaller than the 40h in conventional treatment method, has greatly shortened the treatment time.
embodiment 2, this polyvinyl chloride centrifugation mother liquid waste water advanced treatment recovery method carries out in the steps below: the first step, first polyvinyl chloride centrifugation mother liquid waste water is sent into and adjusted for No. one in pond, the temperature that regulates polyvinyl chloride centrifugation mother liquid waste water is that 30 ℃ or 35 ℃, PH are 8 or 9, phosphonium ion content is 1mg/L or 2mg/L; Second step, polyvinyl chloride centrifugation mother liquid waste water after regulating is sent in HBF one-level biological reaction tank, in temperature, be that 30 ℃ or 35 ℃, PH carry out organic preliminary decomposition under 8 or 9 conditions, the COD clearance that tentatively decomposes to polyvinyl chloride centrifugation mother liquid waste water reaches more than 40%, after preliminary decomposition, obtains once biochemical water; The 3rd step, will be once biochemical water send into and in hay tank, remove suspended contamination, then the once biochemical water after hay tank is processed is sent into and in surge tank, carried out further flocculation sediment, then the upper clear supernate in surge tank is sent in HBF two stage biological reactive tank, in temperature, be that 30 ℃ or 35 ℃, PH carry out under 8 or 9 conditions organicly again decomposing, the COD again decomposing in solution is 40mg/L or 50mg/L, obtains for the biochemical water of common secondary clean, greening use after again decomposing.
embodiment 3, be with the difference of above-described embodiment, the biochemical water of secondary is continued to be fed in adsorption tanks further to absorption polyvinyl alcohol and filters out after the impurity in solution, then obtain reuse water up to standard after the secondary biochemistry water after adsorption tanks are processed is sequentially pumped into MF micro-filtration and RO reverse osmosis two-stage filtration.Adsorption tanks are mainly used in adsorbing some objectionable impuritiess in the biochemical water of secondary, and for example polyvinyl alcohol has had filtering function concurrently simultaneously, and adsorption tanks need carry out timing backwash equally, wash away the impurity adhering to, and avoid affecting follow-up treatment effect; MF micro-filtration and RO reverse osmosis are that two embrane methods are filtered, and can carry out depth type filtration to the biochemical water of secondary, and the reuse water that makes finally to obtain can meet the standard of polyreaction water; The water quality standard of the reuse water after adsorption tanks, MF micro-filtration and RO reverse osmosis detects as shown in table 1.
embodiment 4, be with the difference of above-described embodiment, first the biochemical water of secondary is sent into and adjusted for No. two in pond, after precipitating in No. two are adjusted pond, again clear liquid is continued to be fed in adsorption tanks, when needs carry out back washing to HBF two stage biological reactive tank, directly with the clear liquid in No. two adjustment ponds, HBF two stage biological reactive tank is carried out to back washing.HBF two stage biological reactive tank is carried out to back washing and also can carry out back washing with clear water, but with the clear liquid in No. two adjustment ponds, HBF two stage biological reactive tank is carried out to back washing, can reduce production costs.
embodiment 5, as the optimization of above-described embodiment, with reuse water, the microfiltration membrane of MF micro-filtration carried out to backwash, can reduce production costs.
embodiment 6, and as the optimization of above-described embodiment, HBF one-level biological reaction tank and HBF two stage biological reactive tank are fixed biologically membrane reactor.Fixed biologically membrane reactor is existing known technology.
embodiment 7, and as the optimization of above-described embodiment, in HBF one-level biological reaction tank, the particle size range of filler is that the particle size range of filler in 20mm to 35mm, HBF two stage biological reactive tank is 5mm to 15mm.
the water quality of the reuse water obtaining after processing by the water quality of the polyvinyl chloride centrifugation mother liquid waste water of not processing according to the present invention with according to the present invention detects, and obtains data mean value as shown in table 1:
wherein, what SS referred to is the suspended solid in water, and measuring method is weighting method GB11901-89; What CODcr referred to is the chemical oxygen demand that adopts potassium bichromate (K2Cr2O7) to determine as oxygenant, and measuring method is that potassium bichromate is sent out GB11914-89; What ammonia nitrogen (NH3-N) referred to is the ammonia nitrogen content in water, and measuring method is nessler reagent spectrophotometry HJ535-2009; What total phosphorus (P) referred to is phosphorus content in water, and measuring method is ammonium molybdate spectrophotometry GB 11893-89; What PH referred to is water potential of hydrogen, and measuring method is glass electrode method GB 6920-86.
by data in table 1, can be found out, adopt the present invention to process the reuse water effect that polyvinyl chloride centrifugation mother liquid waste water obtains better, can reach reuse water standard, and successful be stable.
therefore, the present invention is by the combination of biochemical method and multiple physical chemistry method, solve traditional technology polyvinyl chloride centrifugation mother liquid waste water treatment process consuming time, energy consumption is high, the unsettled problem of effect, as the waste water advanced reuse technology of polyvinyl chloride centrifugation mother liquid, there is certain feasibility and superiority, polyvinyl chloride centrifugation mother liquid waste water is first by one-level biochemical reaction groove and secondary biochemical reactive tank, pass through hay tank midway, secondary biochemical reactive tank secondary bio-chemical effluent is out through adsorption tanks, sequentially pump into micro-filtration (MF) and reverse osmosis (RO) after two-stage filtration, water outlet reaches reuse standard, simultaneously, the present invention does not need to adopt inductive reaction device, energy consumption in technique only consumes on pump, therefore, the present invention compares with traditional technology, there is lower energy consumption, so, technical process of the present invention is simpler than traditional method, hydraulic detention time is short, energy consumption is low, successful is stable.
above technical characterictic has formed most preferred embodiment of the present invention, and it has stronger adaptability and best implementation result, can increase and decrease according to actual needs non-essential technical characterictic, meets the demand of different situations.
table 1
Each index in solution
|
PVC mother liquor water quality before processing
|
PVC mother liquor water quality after processing
|
CODcr(mg/L)
|
343
|
2
|
PH
|
8.9
|
7.7
|
S.S(mg/L)
|
12
|
0
|
Turbidity (NTU)
|
4.0
|
0.03
|
Ammonia nitrogen (mg/L)
|
11.7
|
0
|
Total phosphorus (mg/L)
|
0.08
|
0
|
Specific conductivity (μ s/cm)
|
95
|
9
|