Relaimentation And Utilization Of Municipal Wastewater In Sanmenxia, Henan

Sanmenxia,situzted in the west of Henan province,is a typical city with water shortage.And the shortage of water resources has become obstacles constraining urban economic and social development in the future.Municipal wastewater from the city is treated by biological process and then directly discharged into Yellow river,which is undoubtedly a huge waste of water resource from the viewpoint of reclaimation. Sanmenxia Huayang Power Company Limited uses the groundwater as the main source; but now,the urban seWage therewith the stable and reliable origin,completely becomes an alternative.According to the effluent quality of municipal wastewater treatment plant (WWTP)and the environment actuality in Sanmenxia,feasibility of the secondary effluent after advanced treatment regenerated for reuse in cooling water and make-up water in power plant was investigated.Through the analysis of main pollution factors and the investigation of technological measures used for circutating cooling water after advanced treatment,as well as the technique economy analysis and contrast,the advanced treatment process of a whirlpool settling pond+fiber filtering basin+ chlorine dioxide disinfectant generator was selected.Furthermore,the dimensions,main equipments and technical parameters of the unit operation were determined.Polymeric ferric sulfate was introduced to lime-sedimentation for coagulation aid,which could remove 90%of alkalinity and 30%of iron respectively,more than 70%of total phosphorus,and at the same time,more than 30%COD(chemical oxygen demand)and BOD₅(biochemical oxygen demand)in the secondary effluent.Moreover,after filtration by D-type filter tank,the turbidity of effluent was less than 1 NTU,and the coloumess less than 3 dilution times.Finally,the chlorine dioxide disinfection could insure that the fecal coliform counts in the reclaimed water was less than 3 nfc/L. High water quality could be achieved to meet the requirement of cooling water standard in plant water,but not scaling,corrosion.The project will reduce the pollution load of the Yellow River and make significant benefits to local water environment.Meanwhile,engineering implementation would make the original effluent resource recovery,thus reduce the consumption of fresh water,and both of which Can produce good social benefits.With the increasing tension of water resources and the continued growth in the price of water,potential economic benefits of sewage would be greater.