Study on Optimal Culture Conditions of Bioflocculant Produced by Brewery Wastewater and Its Application to Middle Phase Wastewater in Paper Making Process

In order to increase the output of bioflocculant, improve efficiency and stability of flocculation and reduce the cultivating cost, Pseudomonas fluorescensC-2 strain was cultured in brewery wastewater culture medium where brewery wastewater replaced glucose as carbon source and energy source to produce bioflocculant, then the bioflocculant obtained was applied to treat middle phase wastewater in paper making process, and the culture conditions were optimized by orthogonal test. The optimum culture conditions of strain C-2 were as follows: the COD_Cr in the brewery wastewater was 8000 mg-L^-1, the initial pH of brewery culture medium was 7.5, the inoculum size was 2.5 mL/(mL-50 mL^-1), the cultivating temperature was 30degC, the shaking speed was 160 r-min^-1. Under the optimum culture conditions, the maximal COD_Cr and turbidity removal efficiency were 88.26% and 95.92%, respectively. In a word, the method was feasible, it achieved resources utilization of wastes. Brewery wastewater has opened up a new way for carbon source and energy source supply.