| With the development of economics, the spread of cities result in more quantity of water for living and more sewage drainage. Not only it is result in more and more severe water shortage, but also it is very difficult for water treatment plant to dispose of all sewage due to dispersive layout of residential areas connected by large waste pipes which need more money and long time to build it, therefore it is also difficult to meet all the demands. It is more important that existing municipal pipe-netting is far off demands. So it is an effective instrument to solve living sewage pollution and water shortage that building domestic sewage treatment plant to treat domestic sewage and then we can drain it or recycle it to residential areas in existing residential areas by more treatment.In this paper, it is set forth the feasibility, meaning and present problem of domestic sewage's reuse in residential areas. On experiment, it is investigated treatment of domestic sewage on the basis of filtrating by porous ceramic tube with bag hose and ultraviolet light for disinfection. The results are shows as following:(1) It is successful to form compound filter beds on the basis of filtrating by porous ceramic tube with bag hose. When COD<30mg/L in let-in water, the average removal rate of COD is 49% and 55.8% respectively in bag hose â… and â…¡. Chroma in let-out water is lower than 8, the removal rate of chroma is higher than 50%. When SS is 3~ 68mg/L in let-in water, SS is 0~13 mg/L in let-out water. The average removal rate of SS is 52.3% and 62.5% respectively in bag hose â… and â…¡. All the let-out water quality satisfy the water quality criterion inCJ25.1-89.(2) The treating performance of compound filter beds is better than that of percolating material's such as quartzite, in addition, prime cost of compound filter beds is lower than membrane percolating material. The cost of using middle-water will be decreased treated by compound filter beds on mode of automation control.(3) It's better to set up hair side of bag hose in compound filter beds outward. Not only it may insure the micropores not to be clogged, but also the more reasonable fiber moving of hair side, more smooth back washing and forming of first fiber bed, which makes the device running in a better stability.(4) It is effective to slay bacteria in water using photoelectric disinfectant and sterilization technology. In experiment, ultra-violet lamp is set up on exterior face ofcylinder. Intensity of light lost is more than 2/3, the electronic bactericidal device is absent, which cause the average removal rate of bacteria is 41.6%.According to the reported, if they may be set up in a correct place, removal rate of bacteria can reach 96% for ultra-violet lamp and the bactericidal device can reach 98%. If the number of dung coliform bacteria in let-in water is 350 per liter, the let-out water quality will satisfy the water quality criterion inCJ25.1-89, which shows that it is effective to use photoelectric disinfectant and bactericidal technology in water treatment, only if we make good use of the bactericidal means and the ways of fixing.(5) In this experiment, technical parameters are concluded as following: filtrating pressure is 0~0.10MPa, back wash period is 40 minutes , the intensity of back wash is 0.12MPa at beginning lasting 4 minutes.(6) The pressure in back wash due to compressed air have good effect on clean of compound filter beds. In experiment,the pressure of compressed air in air compressing area can offer kinetic energy for let-out water in let-out water area, which improve the cleaning ability of compound filter beds. After cleaning, compound filter beds can filtrate sewage again and again.Through this experiment research, the operational parameters and technology foundations can be offered for project design and running. In the real project, the factors should be adjusted according to the reality to get the best result.
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