Island Rainwater Purification Process Efficiency And Operation Optimization

Island is an important basis for defining maritime boundaries and an important part of land.However,with the increase of development,the provision of fresh water resources on the islands has been increasingly challenged.The scarcity of freshwater resources has been an important element that has plagued development and management.In the local high temperature,high humidity and high salt environment,water resources are an important influence affecting the daily work and life on the island.The collection,storage and purification of rainwater can alleviate the problem of water shortage in islands,enrich the diversity of water supply means,and provide a guarantee for the drinking water demand of residents on islands.Through field investigation and literature investigation,the pollution characteristics of island rainwater were determined.The water quality of conventional rainwater is determined through on-site collection of island rainwater and testing.The water quality of the island's conventional rainwater is relatively good,with a maximum turbidity of 2NTU,no more than 3mg/L permanganate index,no detection of ammonia nitrogen,etc,and only a few indicators fail to meet the requirements of drinking water standards.Potential pollutants such as oil spills caused by aircraft maintenance,pesticides,pesticides,fertilizers and other contaminants that may be present on the island when the runway is put into use are predicted.Based on the existing processing technology of "multi-media filtration-ultrafiltration-Cl O2" in the island,a laboratory pilot plant was built to verify its treatment effect on conventional rainwater sources.The experimental results show that the small test device has a good effect on the treatment of rainwater,and the effluent has reached the drinking water standard.Among them,multi-media filtration has a good effect on the treatment of the hypermanganate index and turbidity in water,with the removal rate reaching 60-70%.The ultrafiltration device can remove most of the permanganate index,turbidity and microbial quantity.After disinfection,the effluent meets the drinking water standard.Three sets of advanced treatment technology for potential pollutants: strengthening sand filter technology,powder activated carbon-strengthening sand filter detection,activated carbon-ultrafiltration technology,pesticides and the handling of oil spill pollution effect is good,removal rate reached around 65%,meet the requirements of the drinking water standard.The analysis and optimization of the existing water purification facilities on the island were carried out.Through regular analysis of the water inflow and outflow trend of the water purification facilities,it was found that the backwashing cycle of multi-media filtration was longer,which was 33 h of continuous operation.After analysis,it was found that after continuous operation for 28 h,the effluent water quality began to decline,and it was recommended to start backwashing after continuous operation for 28 h.It is suggested to increase the amount of chlorine dioxide to increase the amount of residual chlorine in the clear water,so as to inhibit the growth of bacteria.