CN102070240B

CN102070240B - Biomembrane treatment method of two-step wet-spun acrylic fiber wastewater

Info

Publication number: CN102070240B
Application number: CN2009102232996A
Authority: CN
Inventors: 蒋进元; 周岳溪; 常风民
Original assignee: Chinese Research Academy of Environmental Sciences
Current assignee: Chinese Research Academy of Environmental Sciences
Priority date: 2009-11-23
Filing date: 2009-11-23
Publication date: 2012-08-08
Anticipated expiration: 2029-11-23
Also published as: CN102070240A

Abstract

The invention relates to a two-step wet acrylic wastewater biofilm treatment method, which adopts anoxic reaction and aerobic reaction. The present invention can treat DMAC two-step wet-process acrylic fiber wastewater with COD 500-1000mg/L, NH ₄ -N 75-100mg/L, DMAC50-100mg/L, acrylonitrile 0-120mg/L, pH 6.0-9 to COD ≤250mg/L, NH ₄ -N≤4mg/L, DMAC≤2mg/L, acrylonitrile≤2.0mg/L, pH=6.0~9. Its advantages are less residual sludge and short process flow. In addition to being suitable for the mixed wastewater treatment of two-step wet spinning production with DMAC as the solvent, it is also suitable for other solvent spinning production wastewater, wastewater containing acrylonitrile substances, and some printing and dyeing, Textile and petrochemical wastewater.

Description

Two step wet spinning acrylic fiber wastewater biological membrane processing methods

Technical field

The present invention relates to a kind of treatment process of chemical fiber waste water, specifically relate to the treatment process of composite waste in a kind of acrylic fiber production process.

Background technology

China acrylic fiber production process enterprise has 16 families; Add up to 83.11 ten thousand tons/year of throughput; 12 families of operation at present; 80.1 ten thousand tons/year of overall throughputs; Four kinds of technologies of main employing: 1.0 ten thousand tons/year of Sodium Thiocyanate 99 (NaSCN) solvent single stage method wet spinnings (Shandong, Zibo Xue Yin company), 32.1 ten thousand tons/year of Sodium Thiocyanate 99 (NaSCN) solvent two step method wet spinnings (acrylic fibers division department of Oil of Shanghai Petrochemical Company company, Daqing petrochemical company Acrylic Fibers Plant, Anqing Petrochemical branch office Acrylic Fibers Plant, Daqing Refinery company Acrylic Fibers Plant), N; 22.8 ten thousand tons/year of N N (DMF) solvent two step method dry-spinning (Fushun Acrylic Fibers Plant, Qilu Petrochemical Acrylic Fibers Plant, the special acrylic fibers of Qinhuangdao Aurion ltd, Zhejiang Jinyong Nitrilon Co., Ltd.), N; 24.2 ten thousand tons/year of N N,N-DIMETHYLACETAMIDE (DMAC) solvent two step method wet spinnings (Jilin grotesque peak chemical fibre ltd, Hangzhou Wan acrylic fibers ltd, Ningbo Mitsubishi beautiful positive chemical fibre ltd), solvent has nothing in common with each other, and raw material is to be main with acrylonitrile monemer.By 19.8 tons of ton product effluents (domestic certain enterprise's measured value), 1586.00 ten thousand tons of annual efflux wastewater total amounts.Waste water is divided three classes: factory effluent, ground wash-down water and sewage, pollution substance comes from raw material, additive, solvent and raw material and product etc. in the waste water.Sneak into strong acid (sulfuric acid), pH value low (pH=2.5-4) in the waste water, contain poisonous organism, hardly degraded organic substance etc., have vinyl cyanide, vinyl acetate between to for plastic, sodium sulfite anhy 96, ammonium persulphate, ferrous sulfate, sulfuric acid, YD 30 (EDTA), acetic acid, n n dimetylaniline, DMAC and partial polymer (low, high polymers) etc. like DMAC two step method wet spinning production line institute waste discharge pollutant in water.If these waste water directly discharging influence receiving water body water quality with serious harm, the harm Biosafety.It is pre-treatment+anaerobism+aerobic that treatment process that Nitrilon waste water treatment plant adopts is adopted by overwhelming majority enterprises; Water outlet COD is generally 200-400mg/L; Can not reach direct emission standards; Enterprise effluxes after generally chemical fibre composite waste treatment plant and other waste water combination treatment being sneaked in this water outlet; This causes wastewater treatment process to have following problems: the toxic organic compound that contains in (1), the Nitrilon waste water influences the biological treatment system operation, and some toxic organic compound " penetrates " Waste Water Treatment and gets into receiving water body, influences receiving water body water quality; (2), sulfate radical is too high in the waste water, influences the biological treatment system working efficiency, sulfate radical is not up to standard yet in the water outlet; (3), hardly degraded organic substance (like part of auxiliary) increased the difficulty of Waste Water Treatment, the water outlet COD of Nitrilon waste water treatment plant does not reach national emission request; (4), need in the wastewater treatment process to add the multiple nutrients material, must handle excess sludge, increased cost for wastewater treatment.Simultaneously, the Nitrilon waste water treatment system is built in the nineties more, is difficult to satisfy the Environmental Protection in China requirement.

For many years; Chinese scholar is carried out many researchs to the Nitrilon waste water biological treatment; Obtained some achievements, mainly contained: the bioremediation (99112488.X of comprehensive effluent disposal technology for wet spinning acrylic fibers industry (97107031.8,1998 years open), Nitrilon waste water; Calendar year 2001 is open), vinyl cyanide, Nitrilon waste water treatment process (01115864.6; 2002 are open), the treatment process (00129461.X, 2002 open) of acrylic fibers waste water by dry process, the treatment process (02135650.5,2003 year open) of acrylic fibers waste water by dry process, dry method Sodium Thiocyanate 99 be solvent two-step method acrylic fibre wet spinning processing method of industrial waste water (03116574.5; 2004 are open), a kind of acrylon production waste water treatment method (200710176576.3,2009 years open).All these achievements in research do not relate to the handling problem that DMAC is two step wet-spinning factory effluents of solvent; Technological core is the active sludge biological facture, needs a large amount of excess sludge of discharging regularly, and the secondary treatment cost is big; Technical process is long, complicated operation, management inconvenience.

Summary of the invention

The objective of the invention is to propose a kind of two step wet spinning acrylic fiber wastewater biological membrane processing methods, surplus sludge volume is significantly less than activated sludge process, reduces the excess sludge treatment operating costs; Except being applicable to that DMAC is the two step wet-spinning production wastewater treatment of solvent, also is applicable to other solvent spinning factory effluents, contains vinyl cyanide material waste water and part printing and dyeing, weaving and petrochemical wastewater.

For achieving the above object, the present invention adopts following technical scheme:

Developed a kind of microbial film treatment process that can handle two step wet spinning acrylic fiber waste water, the filler ratio of adding is 30.0%-70.0% in the reactor drum, and surplus sludge volume is lower than activated sludge process;

Above-mentioned two step wet spinning acrylic fiber wastewater biological waste water that membrane processing method is handled comprise the composite waste of factory effluent such as acrylic fiber polymerization factory effluent, spinning factory effluent, solvent recuperation waste water, ground wash-down water and sewage and various waste water,

The filler that adds in the biofilm reactor in the above-mentioned two step wet spinning acrylic fiber wastewater biological membrane processing methods is the also fixed filler of floating filler both.

Biofilm reactor is by anoxic, aerobic reaction operation in the two above-mentioned step wet spinning acrylic fiber wastewater biological membrane processing methods, and the order of two kinds of reactions can replace on request, and operating parameter is respectively:

A. hypoxia response:

pH 6.5～9，

Hydraulic detention time 0.0h～3h,

Dissolved oxygen 0.2～0.5mg/L,

Sludge concentration 5～20g/L;

B. aerobic reaction:

pH 6.5～9，

Hydraulic detention time 2.5h～8h,

Dissolved oxygen 2.0～5.0mg/L,

Sludge concentration 5～20g/L;

During above-mentioned two steps wet spinning acrylic fiber wastewater biological membrane processing method operations, anoxic, aerobic two kinds of reactions both can be realized by the time sequence by a reactor drum, also can be realized by spatial sequence by two reactor drums or a reactor drum two sections.

The influent quality of above-mentioned two step wet spinning acrylic fiber wastewater biological membrane processing methods should reach following technical indicator:

COD 500～1000mg/L BOD 250～500mg/L

TOC 180～300mg/L TN 180～250mg/L

NH ₄-N 75～100mg/L DMAC 50～100mg/L

Vinyl cyanide 0～120mg/L pH 6.0～9

The effluent quality of two above-mentioned step wet spinning acrylic fiber wastewater biological membrane processing methods can reach following technical indicator:

COD≤ 250mg/L BOD≤ 10mg/L

TOC≤ 80mg/L TN≤ 50mg/L

NH ₄-N≤ 4mg/L DMAC≤ 2mg/L

Vinyl cyanide≤2.0mg/L pH=6.0～9

Two above-mentioned step wet spinning acrylic fiber wastewater biological membrane processing methods add inorganic carbon in the reactor drum operational process in water inlet, adding concentration is 0.05-3.00mg/L.

Two above-mentioned step wet spinning acrylic fiber wastewater biological membrane processing methods, its nutritive substance dosage is COD: N: P=200: 10: 1.

Two above-mentioned step wet spinning acrylic fiber wastewater biological membrane processing methods, its filler of selecting for use has soft-filler, semi soft packing, elastic filler, Ball-type packing, urethane filler, fibrous packing or other biological filler.

Two above-mentioned step wet spinning acrylic fiber composite waste microbial film treatment processs also are applicable to acrylic fibers, vinyl cyanide, N, the biological treatment of N-acetic acid dimethylamide and chemical fibre manufacture waste water.

The present invention than the advantage that prior art has is:

1, the present invention can effectively handle DMAC two steps wet spinning acrylic fiber waste water, has filled up domestic blank;

2, adopt the microbial film treatment process that adds carrier, surplus sludge volume is few, has reduced the secondary treatment cost;

3, adopt hypoxia response+aerobic reaction, and add inorganic carbon source, effectively denitrogenation;

4, technical process of the present invention is short, can adopt a reactor drum also can adopt two reactor drums, and it is easy, easy and simple to handle to implement;

5, the effective poisonous or hardly degraded organic substance such as the vinyl cyanide in the degrading waste water, DMAC, EDTA of the present invention has reduced the harm of discharge of wastewater to environment;

6, the present invention adopts the microbial film facture, has effectively avoided sludge bulking in the Nitrilon waste water treating processes, has improved the stability of waste water treatment engineering operation;

Description of drawings

Fig. 1 is the concrete process flow sheets of two step wet spinning acrylic fiber wastewater biological membrane processing methods.

Fig. 2 be anoxic, aerobic reaction at a reactor drum by time sequence run-mode synoptic diagram.

Fig. 3 be anoxic, aerobic reaction at three reactor drums by spatial sequence run-mode synoptic diagram.

Embodiment

Below in conjunction with embodiment technical scheme of the present invention is detailed further, protection of the present invention is not limited to following embodiment.

Specific embodiment 1-anoxic, aerobic reaction are pressed time sequence operational mode at a reactor drum

Certain chemical fibre factory's acrylic fiber production process line yearly capacity is 100,000 tons, and the polymerized unit raw material is vinyl acetate, vinyl cyanide and de-salted water, and auxiliary material has ammonium persulphate, sulfuric acid, ferrous sulfate, sodium pyrosulfate etc.; Stoste is prepared by acetic acid and the synthetic DMAC of n n dimetylaniline immediately.Waste water is mainly derived from polymerized unit, and spinning unit, solvent recovery unit also produce part waste water.Waste water treatment plant's equalizing tank receives from all factory effluents and plant area's sanitary wastewaters such as polymerized unit, spinning unit, solvent recovery unit.This composite waste is handled by following method.

Composite waste is promoted among the present invention with pump after physico-chemical pretreatment reaches corresponding water quality requirement.Waste water is evenly distributed in the reactor drum by water distributor (6) after water-in (1) control gets into; Air gets into the back by inlet mouth (3) control and is discharged by aerator (5); The interior air water of reactor drum mixes and contacts with fixed type biological filler (8); Pollutants in waste water obtains removing the back clear water and is discharged by water outlet (7), and circulating water outlet (2) is started working waste water in the reactor drum is circulated when needed, and few part excess sludge is by regularly being discharged by evacuation port (4); Water inlet pH value remains between 6～9 with PLC (9) feedback control; Add sodium hydrogen carbonate solution in the water inlet, adding concentration is 0.5mg/L; Be 6h reaction time, wherein, and water inlet 0.5h, aeration 3h, ST 2h, water outlet time 0.5h; Temperature of reactor is controlled at 25 ℃ ± 1.5, DO=4.5 ± 0.5mg/L during aeration.Work synoptic diagram of the present invention such as Fig. 2, result such as table 1.

Table 1 embodiment 1 result

Unit: mg/L

	COD	BOD	TOC	TN	NH ₄-N	DMAC	Vinyl cyanide	pH
									Water inlet	600～1000	350～500	180～250	180～250	75～108	80～100	85～120	6～9
Water outlet	240	21	77	47	5	0	0	6～9
									Clearance %	75	94	68	75.5	94	100	100

The reactor drum water outlet is according to the difference of various places emission standard; Multiple processing form is arranged: discharge after the next stage reactor for treatment is up to standard (1); (2) be disposed to composite waste treatment plant and further enter receiving water body after the processing; (3) enter the municipal sewage plant and further enter receiving water body after the processing, (4) are back to enterprise after advanced treatment.

Specific embodiment 2-anoxic, aerobic reaction are pressed the spatial sequence operational mode at three reactor drums

Certain chemical fibre factory's acrylic fiber production process line yearly capacity is 150,000 tons, and other situation are with embodiment 1.This composite waste is handled by following method.

Composite waste is promoted among the present invention with pump after physico-chemical pretreatment reaches corresponding water quality requirement.Waste water at first is evenly distributed in the anoxic reacter (1) by water distributor (5) after water-in (4) gets into; Waste water fully contacts the back with anoxic fixed type biological filler (6) and removes the part pollutent; Biodegradability is improved, and water outlet is evenly distributed in the aerobic reactor (2) by water distributor (7) from flowing in the aerobic reactor (2) in the anoxic reacter (1), and air gets into the back by inlet mouth (8) and evenly is released in the reactor drum by reliever (9); Fully contact with aerobe filler (10) behind the air water thorough mixing; Pollutent obtains removing in the waste water, and water outlet is discharged by water outlet (11) through the post precipitation supernatant from flowing in the separator for mud and water (3); When needing, the mixed solution in the aerobic reactor (2) can be circulated to anoxic reacter (1) by pump (13) through circulating water outlet (12).The water inlet pH value of water-in (4) remains between 6～9, and adds sodium hydrogen carbonate solution, and adding concentration is 0.5mg/L; Anoxic reacter (1) hydraulic detention time is 2h, and aerobic reactor (2) hydraulic detention time is 2.5h, and hydraulic detention time is 1h in the separator for mud and water (3); Three temperature of reactor are controlled at 25 ℃ ± 1.5; DO=4.5 ± 0.5mg/L in the aerobic reactor (2).Work synoptic diagram of the present invention such as Fig. 3, result such as table 2.

Table 2 embodiment 2 results

Unit: mg/L

	COD	BOD	TOC	TN	NH ₄-N	DMAC	Vinyl cyanide	pH
									Water inlet	610～1000	350～500	175～256	180～235	79～110	82～100	85～125	6～9
Water outlet	220	20	51	26	3	0	0	6～9
									Clearance %	76	95	79	88	95	100	100

Claims

1. A biofilm treatment method capable of handling two-step wet-process acrylic fiber waste water, the residual sludge amount is lower than the activated sludge process, and the filler dosing ratio is 30.0%-70.0% in the reactor; the biofilm treatment method further Water quality should meet the following technical indicators:

Chemical oxygen demand: 500～1000mg/L, Biochemical oxygen demand: 250～500mg/L,

Total organic carbon: 180～300mg/L, total nitrogen: 180～250mg/L,

Ammonia nitrogen: 75～100mg/L, N,N-dimethylacetamide: 50～100mg/L,

Acrylonitrile: 0～120mg/L, pH: 6.0～9,

The biofilm reactor used in the biofilm treatment method operates according to anoxic and aerobic reactions, and the order of the two reactions alternates as required, and the operating parameters are respectively:

a. Hypoxia response:

pH 6.5～9,

Hydraulic retention time 0.0h ~ 3h,

Dissolved oxygen 0.2～0.5mg/L,

Sludge concentration 5-20g/L;

b. Aerobic reaction:

pH 6.5～9,

Hydraulic retention time 2.5h ~ 8h,

Dissolved oxygen 2.0～5.0mg/L,

The sludge concentration is 5-20g/L.

2. according to the two-step wet acrylic fiber wastewater biofilm treatment method of claim 1, it is characterized in that treated wastewater includes acrylic fiber polymerization production wastewater, spinning production wastewater, solvent recovery wastewater, ground flushing water and domestic sewage.

3. according to the two-step wet-process acrylic fiber wastewater biofilm treatment method according to claim 1, it is characterized in that the filler added in the biofilm reactor is a suspended filler or a fixed filler.

4. according to the two-step wet-process acrylic fiber wastewater biofilm treatment method according to claim 1, it is characterized in that, anoxic, aerobic two kinds of reactions are realized by a reactor by time sequence or by two reactors by space sequence Realized or realized by two sections of a reactor according to the spatial sequence.

5. according to the two-step wet-process acrylic fiber wastewater biofilm treatment method according to claim 1, it is characterized in that the effluent water quality reaches the following technical indicators:

Chemical oxygen demand ≤ 250mg/L Biochemical oxygen demand ≤ 10mg/L,

Total organic carbon ≤ 80mg/L Total nitrogen ≤ 50mg/L,

Ammonia nitrogen ≤ 4mg/L N, N-dimethylacetamide ≤ 2mg/L,

Acrylonitrile ≤ 2.0mg/L pH = 6.0～9.

6. According to the two-step wet process acrylic fiber wastewater biofilm treatment method according to claim 1, it is characterized in that, during the operation of the reactor, inorganic carbon is added to the influent, and the dosage concentration is 0.05-3.00mg/L.

7. According to the two-step wet-process acrylic fiber wastewater biofilm treatment method according to claim 1, it is characterized in that the amount of nutrients added is COD:N:P=200:10:1.

8. according to claim 2 two-step wet acrylic fiber wastewater biofilm treatment method, it is characterized in that, the filler selected has soft filler, semisoft filler, elastic filler, spherical filler, polyurethane filler, fiber filler or Other biological fillers.

9. according to the two-step wet-process acrylic fiber mixed wastewater biofilm treatment method according to claim 1, it is characterized in that the method is applicable to the biological treatment of acrylic fiber, acrylonitrile, N, N-dimethylacetamide and chemical fiber production industrial wastewater.