The Study On Characteristics And Culture Conditions Of Flocculant-producing Microbe

As a new kind of flocculant, microbial flocculant has attracted many researchers' attention and much efficient work on it has been done.So far, researchers have isolated many flocculant-producing strains from activated sludge and soil. Of these strains, many such as Rhodococcus erythroplis S-l, Bacillus sp.A-9 and Aspergillus AJ7002 could produce flocculant with high flocculating activity. On the other hand, the cost of microbial flocculant was very high. Little work has been done about the toxicity of micobial flocculant. The knowledge about the flocculating mechanism of microbial flocculant was still superficial. There are still many problems on the microbial flocculant to be solved.This paper mainly includes six parts. The first part present the screening of flocculant-producing microbe from the microorganism samples: activated sludge and soil. The result of the isolation showed there were many kinds of flocculant-producing microbes existing in the nature. Then five strains(MB6-3, MB6-5, MB6-42, MB6-12 and MB5-ll)with high flocculating activity (flocculation rate > 90%) werechosen and discussed. In the second part, three strains: MB6-3, MB6-5, MB5-11 were chosen and their culture conditions were optimized respectively. The comparision of the culture conditions of the three strains showed MB6-3 was the most rough and most stable flocculant-producing strain.Thus MB6-3 was chosen as the strain which deserves further study. In order to determine the position of the flocculant-producing microorganism in the microorganic system and further understand the properties of flocculant-producing microorganism, the microbe was identified in the following part. And the result of the identification showed MB6-3 was Aeromicobium sp. Then the flocculant was purified and some of its physical-chemical properties were measurated and analyzed. In order to prove the validity of the microbial flocculant, the paper also used the microbial flocculant to treat industial wastewater. The results showed that the microbial flocculant could perform well for some kinds of wastewater. Considering the higher cost of microbial flocculant production, the paper tried to find cheap nutrition for flocculant-producing microbe and bagasse was proved to be available.