The Study On Situ Metabolism Of Chronic Growth Bacteria In Sludge Reduction

As the accelerating of urbanization process, the mount of municipal sewage is growingceaselessly. The treatment of excess sludge produced in the municipal sewage treatmentprocess is one of the biggest problems that the municipal sewage plants face at present. Themethods of current excess sludge treatment are high energy and capital cost with lowtreatment which can not meet the treatment requirement. So find a simple way with highefficiency and low capital cost to treat excess sludge is the focus of current research.The basic point of this paper is chronic growth bacteria isolated from excess sludge andthe hypothesis was proved with the experiment that was presented by predecessors“thesuperiority mixed bacteria-chronic growth bacteria in situ metabolic degradation municipalsewage and achieves surplus sludge reduction technology”. In the experiment, biofilmprocess and stable isotope labeling were used to study the chronic growth bacteria andresearch chronic growth bacteria in situ metabolic degradation municipal sewage and surplussludge reduction technology is feasible, and attempt seek out the new technology in themunicipal sewage treatment process. The result showed that in the continuous inflowexperiment of3different proportions of optimal mixed bacteria（Moraxellaceae:Brevundimonas sp=3:7, Brevundimonas sp: Pseudomonadaceae=7:3, Sphingobacterium sp:Flavobacterium=8:2）, two chronic growth bacteria（Moraxellaceae: Brevundimonas sp=3:7）had the best removemnt of COD、NH3-N、T-N、T-P in the continuous inflow experiment andleast number of bacteria in the outlet which meet the double standard of municipal sewagetreatment and excess sludge reduction. The result of the three mixed bacteria groups labeledby stable isotope showed that two chronic growth bacteria（Moraxellaceae: Brevundimonassp=3:7），the efficiency removemnt of COD、NH₃-N、T-N、T-P in the experiment are83.24%、35.36%、44.46%、45.02%，and the group of chronic growth bacteria–Moraxellaceae had thebest absorption ability of the organic carbon marked by（13）^C, the absorptive amount reached98.16%, which meant this bacteria group had the best treatment of COD in artificialwastewater and could achieve the goal of excess sludge reduction.