Moving Sand Bed Biofilter Applicated In Drain Standard Improvement Of Municipal Sewage Treatment Plant

The dissertation introduced the background and significance of drain standard improvement, explaine the means of third stage treatment with the example of ZhangJiaGang sewage treatment plant. The dissertation introduced the technical characteristics which was fit to use in the third stage sewage treatmentand choiced the dissertation choosed turnplate filter, fabric filter, Moving sand bed biofilter, MBR (Memberance Biological Reactor), deep bed filter to introduce briefly, and compared the advantage and disadvantage of them. Moving sand bed biofilter was choosed primarily to apply in the third stage treatment in ZhangJiaGang municipal sewage treatment plant. We need to organize middle test before the extensive application to verify and test the function of Moving sand bed biofilter. The conclusion of middle test will be adopted as the important dependence to choose third stage sewage treatment technicas applied in extensive application in ZhangJiaGang.The main content of this dissertation is middle test executed on ZhangJiaGang site. The tested object was drain water came from the secondary tank in the end of conventional technics onZhangJiaGang sewage treatment plant. The main aim of this test is, the effect to improve tiny polluted water quality by dosing carbonaceous matter, study the effective to performance of middle test system by change the parameters of sand circle speed, feeding water flow, feeding air flow, difference of inside and outside sand washer water level, height of sand bed etc, study the biological strat-up, inclide the characteristics of removing TP, TN, SS, COD etc, study the limit condition of temperature and pH.Sand filter is the key parts of Moving sand bed biofilter system, thus, the design of sand filter is one of the emphases in this dissertation. Some part of this dissertation take the emphases on introduce the design theory, the design principle of sand lifter, sand washer etc, and concluded the main technical index of active sand filter in this middle test.We did middle test for about 3 months, after the system design, installation. The system runs stably and well, every parameter meets the requirement of design. The dissertation discussed the mechanism of removing SS, anti-nitration to remove nitration, dephosphorization, to meet the guidance requirement of middle test, the daily running, maintance etc. provided the theory guidance and related principles to them.ZhangJiaGang had carried on and have finished the extensive appliment project, after the basic conclusion of this middle test. The sand filter system have runned for more than half 1 year, obtained the prominent economic and social benefits, and guarantee the sustainable development of ZhangJiaGang City.Moving sand bed biofilter technics was fit to remove pollution from mass quantity, tiny polluted water. The middle test and the extensive application in ZhangJiaGang provided the practical thereunder to use Moving sand bed biofilter in the regions of water-recycling, tiny pollition removing from river and lake, tiny pollution removing from industraial water etc. too.