Inverted A~2/O Process For Sewage Study

When the concentration of nitrogen in waters reaches 0.5mg/L, and the concentration of phosphorus in waters surpasses 0.03mg/L,algae will grow rapidly, causing eutrophication of waters. Eutrophication threats the normal function of water environment seriously. Therefore, the effective way to solve the problem of eutrophication is to control the discharge of N&P.A2/O process,which is the most fundamental process of eliminating N&P, but the traditional A2/O process not only result in poor water quality but also there is contradiction between N&P removal. In order to solve this problem, inverted A2/O process is developed which was suited to China's national conditions. It is simple and efficient, it is not only a good choice for the construction of new municipal sewage-treatment plant but also available to the modification of conventional sewage plant. This article takes sanitary wastewater as the object of study, through the traditional A2/O process and inverted A2/O process of comparison tests had confirmed the superiority of inverted A2/O process to removal of N&P.This paper studied the biochemical reaction of biological phosphorus removal. The results indicate this nitrate, that sufficiency gathering the anaerobic phosphorus bacterium Buddhism phosphorus has or not is really not that the oxygen deciding posterior regards attracts sufficient phosphorus prerequisite excessively. The nitrogen affecting system except that the phosphorus microorganism biochemistry reaction process under anaerobic condition composes in reply result is really coming off gets rid of the key factor of phosphorus. Through this experiment, DO, sludge concentration, nitrate, anaerobic water residence time and the sub-point of the inverted A2/O technique influence the research, draw the following conclusions:(1)DO has little efficiency to eliminate the phosphorus, the efficiency of eliminating NH3-N increased with the increasing of DO.(2)Nitrate can affect phosphorus releasing.(3)The efficiency and the velocity of phosphorus uptake reached the highest level in aerobic zone as HRT in anaerobic zone was in two hours. That Prolonging the HRT in anaerobic zone surpasses two hours can not increase the efficiency of phosphorus removal.(4)As the influent was distributed in different places, the contradiction carbon resource will be solved to some degree and the efficiency of N&P removal will be enhanced.