Research On Raw Water From Yangtze River (Chong Qing Segment) By The Integrated MCSR Equipment

For the dispersive, petty and low-level management characteristics of water supply in small town of Three- gorge Reservoir Region, the devise of integrated water supply equipment with the characteristic of low-investment, manageable, efficient and stable effect has the important social meaning.In this situation, the integrated MCSR (Membrane Coagulation and tube Settle Reactor) equipment is designed to treat the raw water from Yangtze River in Chongqing segment. After determination of the kind and quantity of the coagulant, and the cycle of backwash, the experiment was done to remove turbidity, organics and NH4+-N by use of this equipment. The mechanism of the removal of organics and NH4+-N is discussed, and the application of the integrated MCSR equipment in small town of Three- gorge Reservoir Region is also analyzed.Aluminum sulfate, aluminum chloride and polymeric aluminum chloride (PAC for short) were selected to determine which kind is the best coagulant. The quantity of the dosage of coagulants was also tested. And the results revealed that PAC is the best coagulant and its proper dosage is 20mg/l～30mg/l for turbidity removal only. The dosage for organics removal is more than it for turbidity.Backwash the membrane in the cycle of 30min, 40min and 50min respectively, and results indicated that the backwash of 40min is most suitable for the filtration performance of the membrane.Under the condition of 30mg/l～40mg/l PAC and 40mins of backwash cycle, the raw water of Yangtze River was treated by the integrated MCSR equipment. When the concentration of turbidity, UV₂₅₄, COD_Mn, TOC and NH4⁺-N were 220NTU～533NTU, 0.05cm-1～0.17cm-1, 2.70mg/l～3.50 mg/l, 2.3 mg/l～4.2 mg/l and 0.17 mg/l～0.52 mg/l respectively, their removal efficiency reached 100%, 40.6%～50.7%, 67%～74.6%, 38%～42% and 55%～64% correspondingly. The filtration index, J/J0 kept at 95.5% after back-wash, which indicated that the filtration of the MF has good ability of recovery.The effluent water quality of the integrated MCSR equipment can reach the national water quality standard, even exceeds it, and the cost of the equipment and the treatment in use of the integrated MCSR equipment are 9820 yuan and 0.87 yuan/a respectively. So, the technology of integrated MCSR equipment to treat water polluted slightly is feasible and the cost is economic. And the integrated MCSR equipment has good application in small town of Three-gorge Reservoir Region.