Application Study On Treatment Of Swine Wastewater By Immobilized Microorganism

The main purpose of this study is to probe the feasibility of adding immobilized microorganism to improve the function of the traditional three stage treatment system. the traditional three stage wastewater treatment process is popular for the treatment swine wastewater. However, so far this process did not effectively remove nitrogen the discharge quality can't achieve the claim of Wastewater Discharge Quality Standard of 1996.Immobilization of microorganisms has been widely used in the researches applications as a new kind of technology in the engineering fields. As a type wastewater treatment method, the immobilization of microorganisms has the characteristics of high removal efficiency, stability of operation, and less yield of sludge compared with mobilization of microorganisms.In this dissertation, wastewater with swine wastewater is chosen to be treated with imbedded immobilization of microorganisms in the wastewater treatments experiments. With the imbedded material-polyvinyl alcohol, activated sludge is imbedded in the shape of ball and used in the orthogonal experiments of methanol wastewater treatments whose indicator is COD. Then the optimum imbedding conditions of polyvinyl alcohol are determined and performance if immobilized ball are enhanced under the optimum conditions. According to 5 month continuous test experiments, polyvinyl alcohol support still retains good activity, mechanical strength and elasticity. It is fit for treating the swine wastewater because PVA support shows good ability for nitrification and denitrification when it is operated under high dissolved oxygen environment. The best ratio of sodium alginate-polyvinyl alcohol support material is 0.6 %: 9% : 3 %: 3 % for Na-alginate, polyvinyl alcohol polyethylene glycol and dextran. The results of the study tell us that the discharge quality of wastewater treated by adding sodium alginate-polyvinyl alcohol to he traditional three stage treatment process is better than that of traditional suspended sludge method and the process, the treatment processes showed high efficiency in removing nitrogen in the swine wastewater.