| Today, in China, eighty percent of the wastewater treatment plants adopt active sludge method. But there are many shortcomings with these wastewater treatment plants, such as plentiful sludge being remained, unsteady removing state of nitrogen and phosphorus, large area being taken up, large energy sources being consumed and large cost etc. The research for effective, economic, low cost new technology of nitrogen and phosphorus removing becomes more and more urgent in wastewater treatment field.Based on the traditional A2/O process, the anoxic/anaerobic/oxic process without inner circumfluence has been developed with municipal wastewater as treatment aim from Tianjin Jizhuangzi wastewater treatment plant in our research. The removing efficiency of nitrogen and phosphorus has been researched with suspended bacteria and fixed bacteria methods, in respectively. Firstly, the research for aerobic, anoxic and anaerobic section has been developed. Accordingly, the optimum control condition for every section has been acquired. Finally, two systems by coupling of three sections were considered and the removal efficiency for nitrogen, phosphorus and COD has been reviewed under the optimum control condition.As a result, we can conclude that the effluent nitrogen, phosphorus and COD concentrations could meet with the first-grade discharge standard of pollutants for municipal waster treatment plant GB 18918-2002 with two systems and the removal efficiency of fixed bacteria was higher than suspended bacteria method.
|
PDF Full Text Request