| In recent years, water shortage and pollution is deteriorated in China, and the water environment faces huge challenge. Especailly the effluent standards are becoming stricter day by day, which puts forward higher requirements to the removal of pollutants in water. Studies found that Suspended Substance can interfere the determination of COD, and can make the water quality monitoring equipments inaccurate. Besides that, the removal of SS can take away part of organic matter, which have great significance in water treatment area. Membrane separation technology is called "21 century water treatment technology", and it is an important technology to remove water pollutants. However, recent development of Membrane technology is restricted by many factors such as the prices of menbrane products, the complexity of membrane technology, membrane pollution and membrane separation performance. So, it is becoming a hopspt nowadays to develop new membranes which have low cost, simple fabrication process and good separation performance.Based on systemly consulting and fully reviewing the development status of membrane technology, membrane combined process and application in wastewater treatment, membrane preparation technologies and separation technologies in China and abroad were summarized and analyzed in this paper, and researches were carried out as follows according to defect.(1) Aiming at high price of membrane products, complex preparation technologies, easily polluting, hard cleaning, etc, a new type of mechanical membrane were developed by filament winding method. Parameters of mechanical membrane such as average pore size, porosity, flux and film thickness were influenced by factors such as materials, diameter, input diameter, rotation speed and winding layer. The factors influenced mechanical membrane's performance differently, and winding layer had the greatest impact. Three kinds of mechanical membranes with the winding layer of 1,2 and 3 were prepared choosing the best level of all factors, and assembled them according gap filaments from big to small to prepare multi-stage membrane, which realized grade detention for different particles in fluid.(2) Studied the detention performance of single stage and multi-stage mechanical membrane module. Results showed that the detention performance of multi-stage module was better than single stage module, and multi-stage module had longer cleaning cycle. Detention of mechanical membrane removed particles effectivelly, but had no obvious effect on organics removal. Recoil cleaning had good effect for the flux recovery, and the flux recovery efficiency of all the mechanical membrane could reach to 95%.(3) Aiming at the low efficiency for organics removal of mechanical membrane, combined technologies including coagulation-detention by mechanical membrane and coagulation-magnetization-detention by mechanical membrane were established. Coagulation could enhance the efficiency for organics removal, and extend the cleaning cycle. Magnetization could enhance the efficiency of coagulation, while water after magnetization in coagulation experiments had higher turbidity, SS and COD remolve efficiencies. Strong magnetic field of 5500Gs had more obvious effect. Coagulation-magnetization decreased the pollution speed and extended the cleaning cycle of mechanical membrane.(4) Coagulation-magnetization-mechanical membrane reactor was studied to applied in industrial water treatment. The actor was used to deal with the effluent of adjustable anaerobic system, with the magnetization condition of 5500Gs and coagulation condition of 700mg/L PAC+5mg/L APAM. The actor run stably, and after three stage detention, SS was no detected and COD was bellowed 300mg/L in the effluent, which reached to the second grade of National Integrated Wastewater Discharge Standard.
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