| With the development of rural economy and the deepening of village renovation work,the countryside where villagers scattered in the past are planning to live together, and have installed uniform facilities for water supply and drainage.The quantity of rural drainage is far greater than former. If a great deal of untreated wastewater in rural areas discharge concentratedly and nearby, natural environment of the countryside is bound to be polluted.Meanwhile, the quality, quantity and current situation of rural wastewater are lack of the investigation and the previous data is not comprehensive,which cause rural wastewater treatment facilities to design unreasonably. In order to treat rural domestic wastewater economically and properly in south areas,current situation,the quantity and quality of rural domestic wastewater are investigated and monitored in some villages of Hubei Province,and there are appropriate wastewater treatment processes to be recommend.The treatment situation of rural wastewater is investigated in six villages of Hubei Province,the quantity of wastewater is investigated in the villages of Huashan,Erlong and Yinji,and the quality of wastewater is monitored in the villages of Hongxia,Huashan and Yinji.The survey finds that the household water consumption in the countryside of Hubei Province is 50-60L/cap·d; Rural wastewater should be collected and carried by the underground pipe, and wastewater treatment in rural areas should use the processes which invest less money in the process of being built, cost less money in the process of being run,operate and manage easily.The monitoring results of wastewater quality in three villages of Hubei Province show that the quality of wastewater in the village where the most villagers don't feed livestock and where the drainage system is perfect has considerable fluctuations,because of seasonal difference,villagers'different living habits and lifestyles.In winter the concentrations of contaminants in rural wastewater are higher than municipal wastewater.In summer the concentrations of contaminants in rural wastewater are very low,even the wastewater can be discharged directly.The concentrations of contaminants in the wastewater of the village where the most villagers heep livestock are much higher than municipal wastewater because of the drainage system.Rural residents in the building of re-built new village discharge wastewater that the concentration of organic contaminants is lower than municipal wastewater,the concentration of TP is close to municipal wastewater, the concentrations of TN and NH3-N are slightly higher than municipal wastewater.The average concentrations of contaminants in five periods:CODcr 90.56mg/L,BOD5 28.37mg/L,SS 43.14mg/L,TN 27.32mg/L,NH3—N 24.28mg/L,TP 2.33mg/L.The changes of contaminants in the wastewater have some regularity.Through the comprehensive analysis on monitoring the data of rural wastewater quality and investigating current situation of the countryside, it can be seen that there are large effect to the present wastewater quality on the regional differences,the total quantity of rural population,the average discharge loading parameters,the average comprehensive volume of domestic wastewater,the characteristics of different regions in the village,air temperature,the removal rate of contamination in the drainage system,the infiltration of underground water to discharge pipe and so on.According to the survey and the analysis, the treatment of rural wastewater in Hubei Province adopt subsurface flow constructed wetland covering the soil as the core processing unit,which is proposed.For different treatment scale, different influent quality and different effluent quality,a series of treatment processes are recommended,such as"anaerobic tank (or three format septic tanks)", "sedimentation tank and constructed wetland","anaerobic tank and constructed wetland" and "Chemically Enhanced Primary Treatment and constructed wetland",which cost less money or don't cost money during operation.
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