Screening and Application of High Effective Functional Bacteria for Subsequent Treating Leachate Biological Treatment Effluent

Abstract

To improve refractory organic pollutants degradability of landfill leachate biological treatment effluent, high effective functional bacteria for subsequent treating the effluent were cultured by bioaugmentation. Three predominant bacteria for subsequent treating organic refractory pollutants were cultured and screened from sludge in aeration pool of biochemical treatment system. Based on 16S rDNA identification, the three bacteria are named Mari-nobacter (coded Y1), Acinetobacter (coded Y2) and Escherichia (coded Y3), respectively. In this experiment research, the Mari-nobacter had favorable degradability to organic pollutants and the removal of absorbance at 254nm (UV254) of landfill leachate biological effluent reached 63.9%. The experiment also shows that mixed bacteria have more degradability than single bacterium. Functional bacteria were scaling up cultured, and then inoculated into biological-activated carbon (BAC) reactor by physical circle absorption method. The BAC column operating experiment shows that the high effective functional bacteria also have favorable degradability to organic pollutants in the reactor with diversiform ecological environment. The control experiment shows that the natural start-up BAC has significant degradation capacity to organic pollutants with molecular weight M of 10 ~ 5 k Da, while the inoculums' start-up BAC with functional bacteria keeps removal rate of 76.1% to organic pollutants with molecular weight M of 100 ~ 30 k Da, and reaches removal rate of. 80.9% to organic pollutants with molecular weight M exceeding 100 k Da. It was testified that the BAC reactor with functional bacteria can increase biochemical treatment efficiency of landfill leachate, UV254 removal efficiency of BAC with functional bacteria is 12% higher than it of BAC without functional bacteria.