Experimental Study On Treatment Of Low-carbon Sewage By Modified Multi-stages A/O Process

The C/N of Sewage is generally low in our country, how to make full use of itscarbon source is the main problem about sewage treatment process in our country. Modified multistages A/O process had been widespread concerned about people, because ofits unique advantages, and can make full use of carbon source to achieve the most effective treatment effect of wastewater, but it also has some drawbacks. Therefore, this research in real domestic wastewater as the research object, the piecewise water improvedmultistage A/O process, through theexperiment investigates the Modified multi-stages A/O process in sewage main pollutant removal efficiency, nitrification and denitrification rateand the system of influencing factors.The research show that:Modified multi-stages A/O process can effectively using the organic carbon sourcein the sewage, the main pollutants in sewage treatment effect is obvious. System effluent NH₄⁺-N, TN, TP and COD concentration were less than 2.00mg/L, 15.00mg/L, 1.00mg/L, 15.00mg/L, the removal rate is 97.00%, 79.00%, 97.00% and 79.00% respectively. System for each pollutant has better removal effect. And out of the water concentration of COD, NH₄⁺-N, TN were reached “the urban wewage treatment plant emissions standards”?GB18918-2002? in A standard level, TP concentration reached level 1 B standard.By adjusting the system water flow distribution is more than 50%:30%:10%:10%, 25%:25%:25%:25%, 100%:0:0:0, to study the flow distribution ratio on the Modified multistages A/O process, results show that the flow distribution ratio on the system to remove the influence of NH₄⁺-N, COD is not big, but with the increase of the flow distribution system denitrificationand phosphorus removal effect is gradually getting better, with in the scope of the experiment, the flow distribution is more than 50%:30%:10%:10%, the system works best to eliminate the pollutants; Most of the COD?about 68.21%? in anaerobic and anaerobic reactor, through the release of phosphorus, denitrification and cell synthesis effect has been removed, make full use of water,organic matter for the processing of low carbon source?C/N < 4.0? of the citylife sewage is of great importance.In the study of sludge reflux ratio, the influent distribution remained 50%:30%:10%:10%, the return sludge ratio is 60% and 70% when the system effluent TN concentrations were 14.89, 13.16mg/L, TP water concentrations were 0.99, 1.29mg/L, and out of the water concentration of COD, NH₄⁺-N, TN were reached “the urban wewage treatment plant emissions standards”?GB18918-2002? in A standard level, comprehensive consideration, practical for sludge reflux ratio was 60%.When the influent distribution remained 50%:30%:10%:10%, sludge reflux ratiois 60%, hydraulic retention time is 8h, the system of NH₄⁺-N, TN and COD has A better removal effect and that were reached “the urban wewage treatment plant emissions standards”?GB18918-2002? in A standard level, TP concentration reached level 1 B standard.Modified multi-stages A/O process system dealing with low carbon source sewage, TN and COD in anoxic reactor has been removed, NH₄⁺-N and TP get rid of, mainly in the aerobic reactor for the sewage treatment has the vital significance.Modified multi-stages A/O process system has A good ability of nitrification and denitrification, aerobic nitrification rate along the reactor decreasing step by step, the denitrification rate of anaerobic reactor along the increase step by step,nitrification and denitrification of the system efficiency and the nitrification and denitrification rate change is not consistent.