Summary of the invention
The objective of the invention is, according to the high-concentration waste water character of application intermittently discharged, each pollutant is relatively stable in the assurance high-concentration waste water, seeks the storage combination of a best high-concentration waste water; Utilize the inherent nature of waste water to realize reacting to each other between waste water and regulating; According to the pollutent character of mud concentrated supernatant and sludge dewatering equipment filtrate, seek an optimum handling processing method, avoid this part secondary waste water coagulation dosing to handle, reduce added amount of chemical, reduce running cost.
In order to achieve the above object, the present invention is by the following technical solutions: painting wastewater treatment process, it comprises storage pool, comprehensive adjustment pond, coagulation reaction tank, settling tank, sludge thickener and biochemical treatment tank, wastewater treatment process comprises that high-concentration waste water branch matter splits that storage, high-concentration waste water mix adjusting with low concentration wastewater, the waste water after mix regulating is through materialization and biochemical treatment, mud concentrated supernatant and water extracter filtrate waste water adopt precipitation separation technology, the biochemical acidication that adopts adds the SBR treatment process, and method steps is:
(1) high-concentration waste water of application intermittently discharged adopts branchs matter to split storage, and the high-concentration waste water of PH>7 is stored in alkaline high-concentration waste water storage pond, and PH<7 high-concentration waste waters are stored in acid high-concentration waste water store the pond,
(2) determine the high-concentration waste water combined amount according to low concentration wastewater water quality situation, the high-concentration waste water of intermittently discharged is limited the quantity of and is transferred to the comprehensive adjustment pond by moving liquid pump from storage pool, mixes with the low concentration wastewater of continuous blow-down, regulates water quality,
(3) carry out coagulating to mixing the waste water dosing of adjusting back,
(4) waste water behind the coagulating separates at the 1# settling tank,
(5) the isolating mud of 1# settling tank enters sludge treating system, mud concentrated supernatant and water extracter filtrate waste water enter the 2# settling tank and carry out precipitation separation again, clear liquid is transferred to the 1# settling tank and further clarifies, and the isolating mud of 2# settling tank enters sludge treating system again
(6) clear liquid after the precipitate and separate enters hydrolysis acidification pool be hydrolyzed acidifying and SBR biochemical treatment, treat effluent qualified discharge or carry out advanced treatment reuse again.
Described settling tank is horizontal sedimentation tank or vertical sedimentation tank or inclined-plate clarifying basin or tube settler.
The obtained beneficial effect of the present invention is, can reduce occupation of land, civil engineering and the facility investment expense of newly-built sewage work, and processing unit and equipment are few, and is easy and simple to handle, easy to maintenance, running cost is low, treatment effect good.
Embodiment
Now the invention will be further described in conjunction with the accompanying drawings and embodiments, referring to Fig. 1, painting wastewater treatment process, it comprises storage pool, comprehensive adjustment pond, coagulation reaction tank, settling tank, sludge thickener and biochemical treatment tank, wastewater treatment process comprises that high-concentration waste water branch matter splits that storage, high-concentration waste water mix adjusting with low concentration wastewater, the waste water after mix regulating is through materialization and biochemical treatment, mud concentrated supernatant and water extracter filtrate waste water adopt precipitation separation technology, the biochemical acidication that adopts adds the SBR treatment process, and method steps is:
(1) high-concentration waste water of application intermittently discharged adopts branchs matter to split storage, and the high-concentration waste water of PH>7 is stored in alkaline high-concentration waste water storage pond, and PH<7 high-concentration waste waters are stored in acid high-concentration waste water store the pond,
(2) determine the high-concentration waste water combined amount according to low concentration wastewater water quality situation, the high-concentration waste water of intermittently discharged is limited the quantity of and is transferred to the comprehensive adjustment pond by moving liquid pump from storage pool, mixes with the low concentration wastewater of continuous blow-down, regulates water quality,
(3) carry out coagulating to mixing the waste water dosing of adjusting back,
(4) waste water behind the coagulating separates at the 1# settling tank,
(5) the isolating mud of 1# settling tank enters sludge treating system, mud concentrated supernatant and water extracter filtrate waste water enter the 2# settling tank and carry out precipitation separation again, clear liquid is transferred to the 1# settling tank and further clarifies, and the isolating mud of 2# settling tank enters sludge treating system again
(6) clear liquid after the precipitate and separate is regulated laggard go into hydrolysis acidification pool be hydrolyzed acidifying and SBR biochemical treatment through PH, treat effluent qualified discharge or carry out advanced treatment reuse again.
Described settling tank is horizontal sedimentation tank or vertical sedimentation tank or inclined-plate clarifying basin or tube settler.
The branch matter of high density coating wastewater splits storage, the application high-concentration waste water is mainly the waste water of intermittently discharged, and intermittently discharged waste water is mainly derived from the waste liquid of falling the groove of oil removing, phosphatization, electrophoresis and painting process etc., waste strength height, the primary emission amount is big, and water quality is as shown in table 1.
The water quality of table 1 intermittently discharged high-concentration waste water
In order to guarantee the relative stability of high-concentration waste water all kinds of pollution factors in storage pool, be unlikely to take place in advance between the pollutent mutual precipitin reaction, reduce storage pool useful volume and block pumps and associated pipe.Find that by cross matching precipitin reaction can take place immediately for the clear groove waste liquid of electrophoresis and alkaline waste liquor (as: degreasing, table mediation spray paint waste liquid) mixing mutually, and can form bulk viscosity clinker, causes pump and line clogging; And the clear groove waste liquid of electrophoresis mixes mutually with acid waste liquid (as: etching waste liquor), and it is relatively stable to mix each pollution factor of back, and precipitin reaction does not take place each other.The result shows by experiment, as long as carry out the relative stability that the storage of branch pond just can solve all kinds of pollution factors of high-concentration waste water according to the acid-basicity of high-concentration waste water.Technology high-concentration waste water branch matter of the present invention splits and stores is that high density coating wastewater by PH>7 is stored in alkaline waste water storage pond, is in harmonious proportion the high-concentration waste water that sprays paint as degreasing, table and is stored in alkaline waste water storage pond; The high density coating wastewater of PH<7 is stored in acid waste water storage pond, is stored in acid waste water storage pond as phosphatization and electrophoresis high-concentration waste water; Can reduce the number of building storage pool like this, the storage pool utilization ratio is higher, reduces the investment of sewage treatment project.Certainly, various application high-concentration waste waters also can separate storage, so more helps the stable of pollution factor, needs the quantity of storage pool just to increase so, and the storage pool utilization ratio is lower, increases the investment of sewage treatment project simultaneously.
The adjusting of waste water, the low concentration wastewater of continuous blow-down is (as degreasing, the cleaning overflow waste water of phosphatization and electrophoresis ordinary production) directly be discharged into the comprehensive adjustment pond by line-blending, along with the application production time increases, the low concentration wastewater concentration of continuous blow-down is corresponding to be increased, the high-concentration waste water treatment capacity is determined by low concentration wastewater water quality, generally add in the comprehensive adjustment pond and regulate water quality by moving the liquid pump current limliting, arrange the pressurized air stirring pipe or diving mixer is installed in bottom, comprehensive adjustment pond, utilize pressurized air or mechanical stirring mode that mixed waste water is stirred.
The waste water that mixes after regulating rises to the coagulating section through pump, because milk of lime is the good a kind of medicament of less expensive and phosphor-removing effect at present, this process choice milk of lime (or calcium chloride+sodium hydroxide) is as coagulant aids and dephosphorization agent, anionic PAM is made flocculation agent, the waste water after regulating is added above-mentioned two kinds of medicaments carry out coagulating.The removal of phosphorus in the waste water, phosphorus has three kinds to have form in the waste water: organophosphate, poly-phosphate and orthophosphoric acid salt.Two kinds of forms exist after the phosphorus in the phosphorized waste water.In dephosphorization process, phosphorus to have form and solubleness be important factor, in waste water, add medicament and phosphorus reaction and form insoluble phosphate, by precipitation, phosphorus is removed from waste water then.Add lime and phosphate reaction and generate precipitation of hydroxyapatite, press the following formula reaction:
Mole ratio Ca: P is 5: 3 in theory, but because of the formation difference of phosphatic rock, mole 1.3 to 2.0 variations.Xiang Shuizhong adds lime, lime at first with water in the basicity formation precipitation of calcium carbonate that reacts:
Excessive then calcium ion could generate precipitation of hydroxyapatite with phosphate reaction, and therefore required amount of lime mainly is the basicity that depends on waste water usually, does not depend on the phosphoric acid salt in the waste water.
Mud concentrated supernatant and sludge dewatering equipment filtrate waste water adopt the precipitation separation treatment process, and the quality of sludge treatment directly influences the operation of waste water processing station.In order to make mud reach dehydrating effect preferably, 1# settling tank precipitating sludge is promoted to sludge thickener through sludge pump concentrates, the mud water ratio behind sludge dewatering equipment after concentrating drops to 70%~75% by 99%.Big, mobile difference of mud concentrated supernatant and sludge dewatering equipment filtrate waste water SS content and settling property are good, in order to shorten the flow process of this part waste water, near sludge thickener and sludge dewatering equipment, build a settling tank (technology of the present invention is the 2# settling tank), consider cleaning and the convenience of safeguarding, allow this part waste water adopt the open drain to flow automatically to the preliminary precipitation of 2# settling tank elder generation, mud changes sludge thickener over to by sludge pump and carries out concentration.Supernatant liquor is promoted to the 1# settling tank by pump and further precipitates.Clear liquid directly enters biochemical treatment system, because pollutent indexs such as the COD of this part waste water, total phosphorus and SS all satisfy the biochemical treatment requirement, the waste water of mud concentrated supernatant and sludge dewatering equipment filtrate has just avoided secondary to regulate and the coagulation dosing reaction treatment like this, and simplified the treatment scheme of mud concentrated supernatant and sludge dewatering equipment filtrate waste water, can save the chemicals treatment expense like this.
Acidication because the coating wastewater biodegradability is poor, adds sanitary wastewater in hydrolysis acidification pool, because contain the required various nutritive substances of abundant microorganism in the sanitary wastewater, and nutrition is unbalanced in the coated industrial waste water.In hydrolysis section, fermenting bacteria is hydrolyzed to organic acid, alcohols with complicated organism in the waste water (comprising polysaccharide, fat, protein etc.).Producing hydrogen, produce acetic acid bacteria at souring stage is acetate and hydrogen with tunning organic acid and alcohols metabolism, makes macromolecular substance be degraded to small-molecule substance, makes difficult biochemical solid matter be degraded to the soluble substance of easy biochemistry, has improved the biodegradability of waste water.
SBR biochemical treatment process (sequence batch () is generally formed by turns water inlet, aeration, precipitation, left-falling stroke water by one group of four pond and is left standstill, and the waste water of handling through acidication enters the SBR pond, carries air to carry out micro-pore aeration in waste water.Carbohydrate provides abundant nutrition for aerobic microbiological in the water, has accelerated the metabolism of aerobic microbiological, and organism is able to effective degraded in the water under its effect; By the effect of nitrifier, ammonia nitrogen is converted into nitrite nitrogen, nitric nitrogen by nitrated, and then utilizes denitrifying bacteria that nitric nitrogen is converted into nitrogen, thereby reach the purpose of denitrogenation of waste water; Under aerobic, the oxygen alternation condition of holding concurrently, " polyP bacteria " of generation under aerobic condition, can exceed its physiological requirements and from waste water excess ingestion phosphorus, form polyphosphate as reserve substance, the remaining active sludge of venting has also promptly been removed phosphorus from waste water; Mixed solution after the biochemical treatment precipitates in the SBR pond, precipitation is sunk suspended matter in the water (can sink solid) under action of gravity, thereby with water sepn, make water quality obtain clarification, sample examination is qualified in qualified discharge, if chemical examination is defective, carry out the secondary biochemical treatment again, after chemical examination is qualified, qualified discharge again.
Among the present invention:
One, the branch matter of waste water splits storage
Sanitary sewage is stored in sanitary wastewater storage pond after mechanical grille filters, degreasing, table are in harmonious proportion the high-concentration waste water of falling the groove that sprays paint and are stored in alkaline dense waste liquid and store the pond, phosphatization and the electrophoresis high-concentration waste water of falling the groove are stored in acid dense waste liquid storage pond, and the degreasing of continuous blow-down, phosphatization and electrophoresis lower concentration Cleaning Wastewater directly are discharged into the comprehensive adjustment pond.
Two, the adjusting of water quality, the water yield
High-concentration waste water adopts the current limliting batch processing method, and it is fixed that the high-concentration waste water treatment capacity is come according to continuous blow-down low concentration wastewater water quality, and high-concentration waste water is transferred to the comprehensive adjustment pond by moving liquid pump and metering outfit, utilizes pressurized air to stir waste water is mixed.Comprehensive adjustment pond water quality is relatively stable bigger to the subsequent disposal influence, in order to guarantee the relatively stable of water quality in the equalizing tank, according to field operation experiences, the useful volume of equalizing tank generally designs by 8 throughput per hours, both economically like this can guarantee the relatively stable of waste water quality again, process adjustments pool volume of the present invention designs by 8 hours coagulating treatment amounts.
Three, the comprehensive wastewater after the adjusting carries out the coagulation dosing reaction, and this process choice milk of lime is made coagulating agent, and negatively charged ion PAM makes flocculation agent.
Four, the waste water behind the coagulating enters settling tank and carries out solid-liquid separation.
Five, regulate the PH of post precipitation clear liquid, utilize the line-blending principle, acid solution is added in the pipeline, PH is controlled in the 6-9 scope.
Six, the acidifying that is hydrolyzed of the precipitation clear liquid after PH regulates adds a certain amount of sanitary sewage in hydrolysis acidification pool, improve the biodegradability of coating wastewater.
Seven, the waste water behind the acidication flows automatically to the SBR pond and carries out biochemical treatment.According to the number in coating wastewater amount design SBR pond, the SBR treat effluent after testing, qualified back qualified discharge or carry out advanced treatment.
Eight, mud concentrated supernatant and sludge dewatering equipment filtrate waste water adopt the precipitation separation treatment process, near sludge thickener and sludge dewatering equipment, build a settling tank, this technology is the 2# settling tank, clear liquid is transferred to the 1# settling tank by clear liquid pump, and mud is transferred to sludge thickener by sludge pump.
Example one:
Be applied to produce per year the wastewater treatment of 100,000 painting dressing automobiles lines.Comprise following process procedure successively: sanitary wastewater storage pond (HRT=8-10h, in establish pressurized air and stir and lift pump Q=10m
3/ h, H=15m2 platform the using and the reserved), artificial grid gap 5mm, acid high-concentration waste water storage pond (V
Have=270m
3, in establish that pressurized air stirs and lift pump Q=5m
3/ h, 2 the using and the reserved of H=8m), alkaline high-concentration waste water storage pond (V
Have=400m
3, in establish that pressurized air stirs and lift pump Q=5m
3/ h, 2 the using and the reserved of H=8m), comprehensive adjustment pond (V
Have=400m
3, in establish that pressurized air stirs and lift pump Q=50m
3/ h, 2 the using and the reserved of H=13m, principal pollutant are controlled at COD:800-1200mg/l, total phosphorus: 20-40mg/l, SS is less than 200mg/l), dosing and coagulation reaction device (hydraulic detention time is controlled at 35-45min), 1# horizontal sedimentation tank (surface load: 1.0m
3/ m
2* sludge thickener (V h),
Have=140m
3Two are used alternatingly), sludge dewatering (belt filter press bandwidth 1m, strainer scavenging pump Q=4m
3/ h H=40H
2O), 2# horizontal sedimentation tank (surface load: 1m
3/ m
2* h), PH regulates (add acid in the pipeline, PH is controlled at 7.5-9), hydrolysis acidification pool (HRT=7.5h), SBR pond (V
Have=600m
3One group of 3 pond, every pond cycle: 12 hours, wherein intake 4 hours, aeration 8 hours, intaking began aeration after 1 hour, precipitated 1.5 hours, 1 hour (left-falling stroke water yield: the 200-240 ton) of left-falling stroke water, idle 0.5 hour, sludge concentration: 3500-4000mg/L, sludge loading: 0.15KgCOD/KgMLVSS.d, dissolved oxygen is controlled at 2-5mg/L in the pond), Waste Water Treatment water outlet qualified discharge.
Example two:
Be applied to produce per year the wastewater treatment of 200,000 painting dressing automobiles lines.Comprise following process procedure successively: sanitary wastewater storage pond (HRT=8-10h, in establish diving mixer and lift pump Q=15m
3/ h, H=15m2 platform the using and the reserved), artificial grid gap 5mm, acid high-concentration waste water storage pond (V
Have=400m
3, in establish diving mixer and lift pump Q=5m
3/ h, 2 the using and the reserved of H=8m), alkaline high-concentration waste water storage pond (V
Have=600m
3, in establish diving mixer and lift pump Q=5m
3/ h, 2 the using and the reserved of H=8m), comprehensive adjustment pond (V
Have=600m
3, in establish diving mixer and lift pump Q=70m
3/ h, 2 the using and the reserved of H=13m, principal pollutant are controlled at COD:1000-1600mg/l, total phosphorus: 20-40mg/l, SS is less than 200mg/l), dosing and coagulation reaction device (hydraulic detention time is controlled at 35-45min), tube settler (surface load: 1.0mw/m
2* h, different orientation flowing oblique tube precipitation, 55 ° of inclination angle of inclined plane, inclined tube diameter: 75mm), sludge thickener (V
Have=150m
3Two are used alternatingly), sludge dewatering (belt filter press bandwidth 1m, strainer scavenging pump Q=4m
3/ h H=40H
2O), horizontal sedimentation tank (surface load: 1m
3/ m
2* h, in establish pressurized air stirring, clear liquid pump and sludge pump), PH regulates (add acid in the pipeline, PH is controlled at 7.5-9), hydrolysis acidification pool (HRT=8h, interior extension filler 348m
3), SBR pond (V
Have=600m
3One group of 4 pond, every pond cycle: 12 hours, wherein intake 3 hours, aeration 8 hours, intaking began aeration after 1 hour, precipitated 1.5 hours, 1 hour (left-falling stroke water yield: the 200-240 ton) of left-falling stroke water, idle 0.5 hour, sludge concentration: 3500-4000mg/L, sludge loading: 0.15KgCOD/KgMLVSS.d, dissolved oxygen is controlled at 2-5mg/L in the pond), Waste Water Treatment water outlet qualified discharge.
Coating wastewater is handled through processing method of the present invention, and the pollutent of project discharge of wastewater such as the pollutent pH value that monitoring is surveyed, suspended substance, petroleum-type, phosphoric acid salt, oil of mirbane has reached " waste water comprehensive discharge standard " (GB8978-1996) primary standard; Wherein chemical oxygen demand (COD) place to go efficient is 86.7%~89.5%; Petroleum-type place to go efficient is 94.1%~94.7%; Phosphoric acid salt place to go rate is 99.2%.From treatment effect and efficient, the treatment facility of enterprise works well, efficiently.
The present invention adopts branch matter to split storage, the high-concentration waste water current limliting is handled and precipitation separation technology, and process layout is reasonable, and technical feasibility has certain innovation; The raising that this not only helps waste water treatment efficiency embodies technology and economic unification, and most important to the stably reaching standard of the steady running of total system and water outlet; Treatment facility is simple in structure, and processing unit is few, and less investment is handled structures and plant factor and is stabilized in more than 95%, and operation and maintenance are convenient; Compare with traditional coating wastewater treatment process, engineering investment cost is low, has saved to add dose, and sludge yield also reduces to some extent, has reduced working cost to a certain extent; And stable the reaching " waste water comprehensive discharge standard " that has guaranteed treat effluent water quality be primary standard (GB8978-1996).