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The utilization of bioaugmentation in constructed wetland can enhance the effect of organic matter removal from wastewater. Obtaining effective COD degrading bacteria plays a key role in bioaugmentation. In this paper, in order to improve the capacity of organic matter removal of constructed wetland, four kinds of effective COD degrading sprains (A2,A11,B1,C4) were obtained from soil of constructed wetland by the way of segregation, primary screening and secondary screening. Through the test of microorganism construction to acquire matching groups with better growth situation and the test of technical conditions optimization inspecting the influence of PH, temperature and rotate speed of incubator shaker on COD converting rates, group A2A11,A11B1,A11C4 and B1C4 were acquired, among which the group B1C4 had the highest COD converting rates (73.74%) when PH was 6.8, temperature was 20 and rotate speed was 100r/min. Using the method of 16S rDNA sequence determination, we observed that sprain B1 had the most similarity with Bacillus simplex (T); DSM1321T; AJ439078, 99%, belonging to bacillus, and sprain C4 had the most similarity with Pseudomonas stutzeri (T); ATCC 17588; AF094748, 97%, belonging to Pseudomonas.

We isolated flocculants-producing bacteria F2 from soil. It shows high and stable flocculating activity for Kaolin clay suspension. In order to increase yield of flocculants, we need determine the optimal obtained time. We measured the changes of several parameters using shaking flask experiment, including flocculating- rate, the content of polysaccharide, protein and glucose. It’s showed that the optimal obtained time of bio-flocculants is 21 h. And we built the model about the production of bio-flocculants. Through the comparison of experimental data and the corresponding calculated values from the models, we found that the data joint well and the model can provide theoretical basis for Industrialization of bio-flocculants.

This work investigated the effect of substrates on de-emulsification capability and the growth of a bacillus sp. (screened by our laboratory).The biomass and de-emulsification ratios(DR) of cultures grown in substrate with the different nutrients (glucose, liquid paraffin, NH4NO3 and yeast) were determined. In the orthogonal tests, the significant of de-emulsification capability in turn is glucose>liquid paraffin>yeast>NH4NO3. The glucose is the highest effect of nutrients on de-emulsification capability and growth. The de-emulsification ratios(DR) and the glucose utilization ratios increase simultaneously at log and lag growth phase. Measurements of the liquid paraffin residue indicates that 30.1% liquid paraffin in substrate is consumed and used in inducing the demulsifying compounds production rather than the increase of the biomass. The culture grown in substrate with 2%~5% liquid paraffin exhibits highest de-emulsification ratio(DR). The contents of yeast at 0.8mg/L~1.0mg/L is beneficial to the growth and demulsifying compound production.