A Simulated Experimental Research On Treating Rural Domestic Sewage Through A Stabilization Pond Process

The vast majority of rural living sewage is untreated and discharged directly nearby, which causes serious pollution to surface water source in the rural areas and brings great inconvenience for the life of people living there. Based on the actual condition of our country, how to improve rural living environment on the premise of economic permission has become China's environmental protection department and the related workers issues that need to be solved.Based on the analysis of treatment technology about rural domestic sewage at home and abroad and the quality of rural domestic sewage, the simulated experimental research on treating rural domestic sewage through a stabilization pond process has been carried out, major factors, which could influence reactor treatment effect, such as HRT, aeration time, C/N, pH, and temperature were analyzed. Main results were as follows:Through experiment; we learned that removal rate of COD, ammonia-nitrogen, and TP increased gradually in the stabilization pond process with the increasing of HRT. Integrated COD, ammonia-nitrogen, and TP treatment effect into account, HRT was as 32h in an aerobic pond, HRT was set to 3d in a facultative pond. Compared with three stages of 3h, 4h and 5h aeration time, we surveyed influence and role in the stabilization pond process. The results showed that the effluent COD can reach stably the standard. However, in the current influent quality conditions, for the ammonia-nitrogen and TP, 3h was significantly deficiency, the effluent of ammonia-nitrogen and TP have appeared ever the phenomenon of non-compliance .Water quality can all reach the standard when the aeration time was 4h and 5h. Using 4h as aeration time can save operating costs. Removal effect in an aerobic pond was slightly better than removal effect in a facultative pond. We compared with changes of removal effect of four stages while COD/NH3-N was respectively 9, 10, 11, and 12. At this time, with the increases of COD/NH3-N ratio, COD removal efficiency increased slightly in the aerobic pond and facultative pond. Removal efficiency of ammonia-nitrogen increased more obviously. TP removal efficiency changed little.Through the test study, pH was respectively 7.0, 7.5, 8.0, 8.5, we daily monitored COD, ammonia-nitrogen, TP. It's informed that the effect of COD removal wasn't large when the test changes in pH of influent. The average removal rate of ammonia-nitrogen was beneficial. When the pH was 7.0 ~ 8.5 at the time the pH was in the range of nitrification. TP removal was beneficial when influent pH maintained between 7.0 and 7.5.Integrated above on the monitoring results of COD, ammonia-nitrogen, TP, when the pH was 7.5, it was conducive to the removal effect of simulated domestic wastewater in rural areas. Through the study on 16℃, 21℃, and 28℃,COD, ammonia-nitrogen, and TP increased with increasing of temperature in an aerobic pond and in a facultative pond. Removal effect was significant.Under the optimal parameters, stabilization of the pond process can be use to handle rural domestic sewage. The treatment effect was stable. The effluent quality met the national discharge standard. That was to meet water quality requirements. The average removal rates of COD, TP, and ammonia-nitrogen were respectively 89.6%, 83.2%, and 86.0% in an aerobic pond reactor. The average removal rates of COD, TP, and ammonia-nitrogen were respectively 86.9%,78.3%å'Œ77.4% in a facultative pond reactor. Sludge activity was stable.In order to enhance the removal effect of pollutants on the stabilization pond under low temperature; through added the porous spherical filler, soft fiber filler, and semi-soft filler in the Stabilization pond, and compared to treatment effect. The test results proved that removal effect of COD, ammonia-nitrogen, and TP have been further improved after adding to fillers. The effect of semi-soft filler was most evident. The average removal rate of COD, ammonia-nitrogen, and TP reached respectively 91.9%, 95.8% and 93.3%, making micro-organisms attached to the surface for better growth and more effective treatment.Based on laboratory studies above, we were proposing control of operation cost at last according to location, natural conditions, and characteristics of water quality and water quantity in the Xinhe village of demonstration area-Yian.