| For the alcohol industry, it is an urgent problem that how to make good use of the nutritious waste liquid of alcohol. For the production of microbial flocculant, how to reduce the training cost and the extract cost and come true large scale industrial production has been the most important problems that should be solved. For biological deodorant research, the main issue of is screening efficient deodorant strains, improving the efficiency of biological deodorization method, and looking at ways of culturing deodorant strains cheaply. To solve all of the above problems, the waste liquid of alcohol was used as the use of as a medium to culture the bacteria which has flocculation function. And alcohol waste water provides a good medium for growth of bacteria, which makes the best use of nutritive material at waste liquid of alcohol to produce microbial flocculant and microbial deodorant which can be used to treat heavy metal wastewater and odor gas respectively.The strains producing flocculant ZJ-15 was selected by continuously cultivated in waste liquid of alcohol. The optimal culture conditions of ZJ-15 was that:waste liquid of alcohol which was diluted 20 times, initial pH of medium was 6.0, fermentation temperature T was 28 ℃, rotation speed was 120rpm, inoculation was 3%, liquid volume was 100mL/250mL, and MgSO4 · 7H2O was 0.5g/L without adding. Under the better culture conditions, the concentration of the bacterium which has been fermented for 48 hours was close to 6.78g/L, the utilization of COD was39.23%.It was proved by products application test microbial flocculant have excellent absorption characteristics of heavy metals Pb, Cu, Cd, but not for absorbing Zn. It was an effective method to treat the low concentrations of heavy metal waste water, such as mine water inflow, mineral water, mine water by microbial flocculant, which was simple and inexpensive for treatment of heavy metal pollution. The analysis of the mechanism of absorbing and flocculating heavy metals by microbial flocculant was investigated. The SEM result presented that there are many pore at the surface of microbial flocculant before absorbing and flocculating heavy metal ion. But after absorbing and flocculating, the pores disappeared, and villous crystal existed. The XPS result showed that Pb, Zn, Cu, Cd valence didn’t changed after adsorption and flocculation by microbial flocculant.The FTIR result presented that the main effective component of microbial flocculant might be carbohydrate and phosphate, the mainly groups included hydroxyl group, phenolic hydroxyl group, phosphate group and amide group. Finally, combing the analysis of SEM, XPS and FTIR, it can be surmised that microbial flocculant have excellent absorption characteristics due to the abundant surface functional groups which can be reacted with heavy metal ion. Three strains (CX-2, CX-15, CX-47) which had the higher ability of deodorization were selected from activated sludge after domestication, separation, purification and screening. Then those strains were selected by continuously cultivated in waste liquid of alcohol. The optimal culture conditions of this mixed bacteria was that:alcohol wastewater which was diluted40times, initial pH of medium was 6.0, fermentation temperature T was 30℃, rotation speed was 140rpm, inoculation was 3%, liquid volume was 80mL/250mL, without adding MgSO4 · 7H2O and CaCl2. Under the optimized culture conditions, the concentration of bacterium which have be fermented for 48 hours was close to 11.65g/L, the utilization of COD was 63.62%.By observation of bacterial colony morphology and 16SrDNA identification, it was found that the CX-2 and CX-15 strains was identified as Pseudomonas putida,CX-47 strains as Bacillus subtilis.The engineering application of microbial deodorant products were also examined in this research. On the one hand, the application of microbial deodorant as circulating spray inoculation quantity in biological washing method was studied, the results showed that the removal rate of H2S and NH3 was high, when the inlet flow (gas residence time) were 1.0m3/h, inlet concentration of H2S was 1.0 mg/m3, inlet concentration ofNH3 was 0.8mg/m3,and the better of circulating spray inoculation quantity was 20.0L/h, respectively, the removal rate of H2S could reached 97.4%,and the removal rate of NH3 could reached 92.1%.On the other hand, this research showed that microbial deodorant can effectively treat unorganized garbage stench, and had a longer duration. After spraying microbial deodorant for 1 hour, the concentration of H2S and NH3was significantly decreased to 0.008 mg/m3,0.014mg/m3respectively, and maintained a low concentration. |
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