| Landfill leachate is a kind of wastewater with high concentration and toxic, whose composition is complexed and containing a lot of organic compounds which is difficult to biodegrad, what′s more, there are many kinds of heavy metal, and the concentration of COD and NH3-N is very high, which result to the large fluctuations in the water quality. At present, there are many methods to treat the landfill leachate at home and abroad, but the research of united technologies of bio-flocculants precipitation and bioaugmentation technique to the treatment of landfill leachate is rare. In the other hand, it may lead to a low removal rate of COD and NH3-N when use traditional biological process to treat the landfill leachate, but united technologies of bio-flocculants precipitation and bioaugmentation technique can solve this problem effectively, which can degrade the pollutants effectively, what is more important, the bioflocculant is nontoxic and harmless, so it is very important for the people′s health and protection of environment.In this paper, the strain of high-efficiency bioflocculant-producting, which was named Be-3, was screened from the soil, and it was identified to be the Staphylococcus by the shape characteristic of the Be-3, and the result of gram stain test and physiological biochemical test.In order to get the highest flocculating activities, the optimal culturing condition was studied in the paper. The results of the experiment show that the optimal culturing condition was as follows: the carbon source is the composition of 10 g·L-1cane sugar and 10 g·L-1lactose, the nitrogen source is the composition of 0.5 g·L-1urea, 0.2 g·L-1yeast extract and 0.5 g·L-1potassium nitrate, the inorganic salt is the composition of 2 g·L-1potassium dihydrogen phosphate, 5 g·L-1potassium phosphate dibasic and 0.1 g·L-1sodium chloride. When the Be-3 was cultured at 30℃with the initial pH being 6.5 and the rotation speed-140 r·min-1 for 42 h, the flocculating activities achieved over 96%.In order to investigation the application area of the bioflocculant, bio-Flocculants precipitation was used to treat the simulated wastewater, such as methylene blue solution, Kaolin solution, Humic acid, Sludge wastewater, whose concentration is 1g·L-1,the result of erperiment show that bioflocculant have a good treatment effect on the turbidity of simulated wastewater, the removal rate of turbidity achieve 98.2% to the kaolin solution.The united technologies of microwave fenton process and biofluccents precipitation process was selected to pre-treat the landfill leachate of changshengqiao in Chongqing, when the landfill leachate was diluted to 100 times, pH was 3.0, microwave irradiation 320W for 6min, adding 8ml Fe2+ at 8mmol·L-1, 1ml H2O2, removal rate of COD and NH3-N was best, which is 98.74% and 55.71% respectively. Then the landfill leachate was treated by biofluccents precipitation process, and result against the removal rate of COD and NH3-N show that the best flocculation condition was as follows: when pH is 7.0, bioflocculant dosing quantity is 1.0ml, 1%CaCl2 solution dosing quantity is 1.0ml, and mixed them at fast speed 1min, low speed at low speed 3min, the concertain of COD is 2mg·L-1, a-nd the concertain of NH3-N is 0.039mg·L-1.In order to get the pure products of flocculants, the paper used acetone to purified the bioflocculant preliminary, the yield of flocculant is 38.4mg·L-1, the result of color experiments and spectrum of bioflocculant show that the bioflocculant was mainly composed of polysaccharide, and was more thermostable, which implied that the bioflocculanthas a good industrial prospects.
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