Study On Optimal Design And Treatment Effect Of Comprehensive Utilization System Of Rainwater And Gray Water In A Primary School In Yixing

At present,the shortage of water resources is becoming more and more serious,and the utilization of unconventional water resources has been paid more and more attention.In this paper,an optimized design of rainwater and gray water comprehensive utilization system has been built in a primary school in Yixing,and the operation effect of rainwater and gray water treatment system is studied.On this basis,the guidelines for the implementation of local rainwater utilization are summarizedThe research on the treatment effect of rainwater collection system shows that the main pollutants in rainwater are COD,SS and TP.The concave green space has a certain purification effect on COD and SS.Multi-media filter is the main treatment unit for pollutant removal.Multi-media filter has good removal rate for COD,SS and TP,but the treatment effect of ammonia nitrogen is poor.The average water quality of SS,TP,COD and NH4-N in the effluent of rainwater treatment system is 14 mg/L,0.38 mg/L,21.5 mg/L,0.38 mg/L,respectively.It is superior to "water quality engineering design,construction and acceptance standard of Jiangsu province construction standard"(DGJ32/JT90-2010)After treatment,rainwater is applied to the water quality of road sprinkling and urban greening.In the process of system operation,the main factors that affect the effect of rainwater treatment are the drought days before rainfall and the higher removal rate of pollutants in the earlier drought daysThe direct culture sludge is used to debug the gray water treatment system.The aeration tank sludge culture and the biological contact oxidation tank were successfully carried out.The results of pollutant removal in gray water treatment system show that the main pollutants in gray water are COD,SS,TP,ammonia nitrogen.The average removal rates of COD,SS,TP and NH4-N were 81.8%,82.1%,65%and 62.4%,respectively.The average effluent concentration was 34.6 mg/L,8.94 mg/L,0.37 mg/L,5.1 mg/L,respectively.It is superior to "water quality engineering design,construction and acceptance standard of Jiangsu province construction standard"(DGJ32/JT90-2010).Temperature and pH have effects on the treatment effect of gray water treatment system.When the temperature is lower,the removal rate of COD and ammonia nitrogen decreases.And the removal rate of COD,TP and NH4-N under the conditions of partial acidity and partial alkalinity was lower than that of pH,and the removal rate of pollutants under neutral conditions was lower than that of pH.In a primary school in Yixing rainwater resources system as the foundation,summarizes the domestic and foreign laws and regulations,standards and related research results and practical experience,combined with the local climate and geographical features,the "centralized residential area rainwater resources,the implementation of guidelines".Manual from the preparation background,scope of application,target requirements,rainwater resources,technical requirements,as well as acceptance and maintenance of several aspects of the centralized residential area rainwater resource implementation requirements are described.