| Along with rapide growth of world population and social economy development, the people's demand quantity of fresh water is more and more. At the same time, the discharge of municipal sewage and industrial waste also grows day by day, and the phenomenon, water eutrophication gets more serious. Biological nitrogen removal processing is to improve the quality of municipal sewage, one of important ways to guarantee water environmental security. Enhancing the processing efficiency, reducing cost, and ensuring harmonious operation are the goal which the treatment pursues. It is thought that the bio-electrode process is a kind of biological nitrogen removal processing, which has the best foreground so far.The biofilm-electrode reactor is introduced to the SBBR of sewage treatment for the first time, and as the base of developing a kind of new technology for waetewater treatment in the paper. The electrode-SBBR process combined the strongpoints of electro-chemical method and biology method. The high-efficiently and cleanly denitrification can be realized by this process. Application of various methods for treatment of nitrate polluted municipal sewage was investigated experimentally in this paper. The range of the optimum process condition was studied. When temperature was 30℃to 32℃, the pH of aerated phase was 7 to 8, the pH of anoxic phase was 6.5 to 7.5, operation cycle was 495 min, water feed 30min, anoxic 90 min, aerated 210 min, settle 120 min, decant 30 min, unused 15 min; the hydraulic retention time (HRT) was water feed 30 min, anoxic 30 min, aerated 210 min, settle 180 min, decant 30 min, unused 15 min, the electric current was 120 mA, the DO of aerated phase was 3 to 4 mg/L, the C/N concentration ratio was 7, nitrate concentration was 40 mg/L. Under the best operating condition of 495 min, it was confirmed that a higher nitrate removal ratio can be achived 89.48%, and the range of TN (total nitrogen) removal ratio was 66.67% to 84.37%. When the system is normal and stable, biofacies was observed by microscopy during stable operation cycle, and it knew the species and relation of the species in the reactor, and the biologic influence on the efficiency of denitrification.Denitrification was investigated experimentally in electrode-SBBR intimidated by Cu in this paper. The cathode and anode uesd graphite electrode, and the denitrifier that was domesticated by current and copper ion were immobilized on the soft carrier and the facies of cathode. The concentration of copper ion was 0, 2, 4, 6, 8 mg/L to domesticate, and the copper ion put in every 24 h. After 24 h denitrification was inspected, the microorganism adapted increscent concentration of copper ion. In order to find the characteristic of denitrification in electrode-SBBR, series of separate experiments were carried out different with operation cycle, electric current, DO, C/N. It can be concluded that better effective removal of indicators under the condition of T=30～32℃, the pH of aerated phase was 7 to 8, the pH of anoxic phase was 6.5 to 7.5, I=90 mA, the DO of aerated phase was 3 to 4 mg/L, C/N=8, and effluent concentration of indicators can achieve emission standards of china.Finally, some further researches were suggested on the following derections, validated experimentation of electrolyse and gas production in denitrification phase, the choice of carrier, electrode material and multi-cathode system, isolation and identification of microbial strain, screening and domesticating of dominating microbial species on the cathode and carrier and so on.
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