Biochemical process is administered electroplating wastewater technology
Technical field
The present invention relates to the technology that a kind of BM of utilization function cenobium is handled electroplating sewerage.
Background technology
The environmental improvement engineering is a major issue of benefiting the nation and the people.The unprocessed water body that directly enters of heavy metal wastewater thereby can cause water pollution, influences the water ecology balance.
At present, the method for the processing electroplating sewerage that domestic employing is maximum is a method of chemical treatment, removes each heavy metal species by precipitation, throwing out, makes wastewater to reach standard.The discharging chromate waste water is separate treatment separately, also need have high input to quantize to learn medicament, and running cost height not only, and produce a large amount of mud, easily cause secondary pollution;
Electrolytic process is handled electroplating sewerage, is to utilize redox principle, with Cr
6+Be reduced into Cr
3+, remove the Cr in the waste water
3+But can not handle composite waste, the concentration and the water yield of single heavy metal all had certain limitation;
Ion exchange method is handled electroplating sewerage, complicated operation, and resin is saturated fast, and regeneration needs to consume a large amount of acid, alkali, and running cost is too high;
The iron filings method is handled electroplating sewerage, and its parallel-adder settle-out time is short.As time goes on, effluent quality is poor, purification rate is low;
The microbiological treatment electroplating sewerage is better than aforementioned processing method effect, administers the electroplating wastewater new technology as the microbial method that patent CN1096769A provides, to Cr
6+Removal obviously can not be up to standard fully but integrative electroplating waste is handled, especially nickel in the waste water and zinc.Because the limitation and the unstable of its technology also can't be applied at present to big yield, high-concentration electroplating wastewater.
Goal of the invention
Present situation in view of present various improvement electroplating wastewaters, the objective of the invention is to develop a kind for the treatment of electroplating waste water with micro-organism that utilizes, provide a kind of high-level efficiency, consistent, anti-shock loading and running cost low, be applicable to that the biochemical process under big yield, the high density situation administers the technology of electroplating wastewater.
This biochemical process is administered the electroplating wastewater technology characteristics and is to utilize BM function cenobium that electroplating wastewater is handled, and treatment step is as follows:
1), electroplating wastewater is introduced equalizing tank, regulates its water yield, homogenizing water quality;
2), with the process of the electroplating wastewater in equalizing tank first step static mixer, in first step static mixer, add the BM function yeast simultaneously, add-on is the 1/50-200 of electroplating wastewater flow in the first step static mixer, enter BM reactor or pond, carry out the one-level biological respinse, stopped 1-2.5 hour;
3), will carry out electroplating wastewater behind the one-level biological respinse through second static mixer, adding content is 30% sodium hydroxide solution, add-on is decided on electroplating wastewater acidity, adjust pH value to 7.0-8.5, or add the BM function yeast simultaneously, its add-on is the 1-3 ‰ of electroplating wastewater flow, carries out the secondary biochemical reaction precipitation and filters, and stops 2.5-4 hour;
4), the electroplating wastewater after will filtering through the secondary biochemical reaction precipitation promptly reach the primary standard among the national sewage comprehensive emission standard GB8978-1996;
5), the throw out with the Two-Stage Biochemical reaction is collected into mummification of sludge drying pond or press filtration after concentrating, recyclable heavy metal.
The electroplating integrated waste water optimum process condition of above-mentioned processing is: the waste water pH value is 3.0-8.0,10~50 ℃ of temperature of reaction.
Above-mentioned biochemical process is administered the described BM function yeast of being made up of desulfovibrio, desulfurization coccus, desulfurization band bacterium of electroplating wastewater technology, and growth conditions is an anaerobic growth, and temperature 20-40 ℃, growth time is 12-24 hour.
The BM function yeast exists the mutual cooperation of chemistry, physics, biological three levels through secular screening and cultivation between them.Therefore, the BM cenobium has electrostatic adhesion, valence state conversion, complexing, flocculation and buffering pH value five functional, with the surface of the heavy metal ion enrichment in the waste water in the BM bacterium, through solid-liquid separation, after entering the filtration of secondary biochemical reaction precipitation again, can make the electroplating wastewater qualified discharge.The invention has the advantages that:
1, waste water treatment engineering will thoroughly solve the pollution problem of the factory effluent of enterprise to environment.
2, the electroplating wastewater after the biochemical treatment fully can reuse to the very strict place of water quality requirement, reuse generally is not less than 50%.
3, with conventional processes one by one chemical method compare, can save a large sum of working cost and maintenance cost.As in strict accordance with country-level effluent standard, 1 ton of waste water of chemical method usually conduct needs 3-8 unit, and only about 1.2 yuan, the two differs about more than 2.0 yuan to biochemical process.
4, the body refuse amount is few, and metal is recyclable, non-secondary pollution.The BM bacterium waits effect to form the particulate state sediment by absorption the heavy metal ion in the electroplating wastewater, and its quantity of slag seldom.Because heavy metal content is higher in the mud, mud concentrated handle, heavy metal can be reclaimed or industrial chemicals.After extracting the mud residual content still less, its heavy metal remaining quantity is lower, thereby has avoided secondary pollution effectively.
In sum, the present invention utilizes the BM function yeast to handle electroplating integrated waste water, overcome existing chemical method, electrolytic process, ion exchange method deficiency, had the advantage that chemical method, electrolytic process, ion exchange method, microbial method etc. are administered electroplating wastewater concurrently, has the unique technique advantage, can handle integrative electroplating waste, and processing power is strong, efficient is high, bacteria using amount is few, stable effluent quality, anti-shock loading and running cost is low, operational administrative is easy, be applicable to the electroplating wastewater of handling big yield, high density.
Accompanying drawing is described
Fig. 1 process flow sheet of the present invention
Embodiment
Embodiment 1:
Discharge 400 tons of electroplating integrated waste water Chongqing Electroplate Factory day, former water index: (local Environmental Protection Agency monitoring product acceptance data)
PH |
Cr
6+ |
TCr |
Ni
2+ |
CODcr |
Petroleum-type |
3.05 |
77.1 |
127 |
4.89 |
124 |
5.68 |
Wastewater flow is 20 tons/hour, 25 ℃ of temperature, adding 400 liters/hour BM function yeast enters the BM reactor through first step static mixer and carries out the one-level biological respinse after 1.0 hours, add 30% sodium hydroxide solution, pH value is adjusted to 7.0, through second stage static mixer, carry out the secondary biochemical reaction precipitation and filter stop 2.5 hours, the water outlet result is:
(local Environmental Protection Agency monitoring product acceptance data)
PH |
Cr
6+ |
TCr |
Ni
2+ |
CODcr |
Petroleum-type |
7.72 |
0.102 |
0.296 |
0.108 |
38.5 |
1.04 |
Primary standard in the national sewage comprehensive emission standard (G88978-1996):
PH |
Cr
6+ |
TCr |
Ni
2+ |
CODcr |
Petroleum-type |
6--9 |
0.5 |
1.5 |
1.0 |
100 |
5 |
Water outlet reaches national sewage comprehensive emission standard fully.
Embodiment 2:
Discharge 1000 tons of electroplating integrated waste water Dongguan Electroplate Factory day, former water index: (local Environmental Protection Agency monitoring product acceptance data)
PH |
Cr
6+ |
Cu
2+ |
Ni
2+ |
CODcr |
Petroleum-type |
3.0 |
58.06 |
2.51 |
5.7 |
51.1 |
1.3 |
Wastewater flow is 50 tons/hour, 50 ℃ of temperature, the BM function yeast that adds 250 liters/hour, enter the BM reactor through first step static mixer and carry out the one-level biological respinse after 2.5 hours, add 30% sodium hydroxide solution, pH value is adjusted to 8.0, through second stage static mixer, carry out the secondary biochemical reaction precipitation and filter stop 4.0 hours, the water outlet result is:
(local Environmental Protection Agency monitoring product acceptance data)
PH |
Cr
6+ |
Cu
2+ |
Ni
2+ |
CODcr |
Petroleum-type |
7.0 |
0.05 |
Do not measure |
0.1 |
49.5 |
0.4 |
Primary standard in the national sewage comprehensive emission standard (GB8978-1996):
PH |
Cr
6+ |
Cu
2+ |
Ni
2+ |
CODcr |
Petroleum-type |
6-9 |
0.5 |
0.5 |
1.0 |
100 |
5 |
Water outlet reaches national sewage comprehensive emission standard fully.
Example 3:
Discharge 100 tons of electroplating integrated waste water Suzhou Electroplate Factory day, former water index:
(local Environmental Protection Agency monitoring product acceptance data)
PH |
Cu
2+ |
Ni
2+ |
CODcr |
8.0 |
11.25 |
12.351 |
69 |
Wastewater flow is 10 tons/hour, 10 ℃ of temperature, adding 100 liters/hour BM function yeast enters the BM reactor through first step static mixer and carries out the one-level biological respinse after 1.5 hours, add 30 liters of/hour BM function yeast and 30% sodium hydroxide solution, pH value is adjusted to 8.5, through second stage static mixer, carry out the secondary biochemical reaction precipitation and filter stop 2.5 hours, the water outlet result is:
(local Environmental Protection Agency monitoring product acceptance data)
PH |
Cu
2+ |
Ni
2+ |
CODcr |
7.0 |
0.017 |
0.248 |
20.0 |
Primary standard in the national sewage comprehensive emission standard (GB8978-1996):
PH |
Cu
2+ |
Ni
2+ |
CODcr |
6-9 |
0.5 |
1.0 |
100 |
Water outlet reaches national sewage comprehensive emission standard fully.
Embodiment 4:
Discharge 700 tons of electroplating integrated waste water Chongqing Electroplate Factory day, former water index:
(local Environmental Protection Agency monitoring product acceptance data)
PH |
Cr
6+ |
Ni
2+ |
CODcr |
3.5 |
65.5 |
30.0 |
102.0 |
Wastewater flow is 30 tons/hour, 15 ℃ of temperature, adding 300 liters/hour function yeast enters the BM reactor through first step static mixer and carries out the one-level biological respinse after 1.5 hours, add 90 liters of/hour BM function yeast and 30% sodium hydroxide solution, pH value is adjusted to 8.5, through second stage static mixer, carry out the secondary biochemical reaction precipitation and filter stop 2.5 hours, the water outlet result is:
(local Environmental Protection Agency monitoring product acceptance data)
PH |
Cr
6+ |
Ni
2+ |
CODcr |
7.0 |
0.012 |
0.045 |
76.0 |
Primary standard in the national sewage comprehensive emission standard (GB8978-1996):
PH |
Cr
8+ |
Ni
2+ |
CODcr |
6-9 |
0.5 |
1.0 |
100 |
Water outlet reaches national sewage comprehensive emission standard fully.