| With the development of social economy and acceleration of urbanization, surface water pollution is becoming more and more prominent, in China, in which sewage pollution has already become its main problem. It is urgent to create new technologies for high efficient sewage purification in order to increase urban sewage treatment rate and to high-efficiently remove organics and nutritional contaminants such as nitrogen and phosphorus. Based upon the complete conclusion about present relative sewage treatment technologies including sequencing batch reactor activated sludge technology, biological film technology and concrete eco-film technology, the SBR technology has been tactfully combined with the concrete eco-film technology in this paper, and the experiments of sequencing batch sewage treatment with intermittent inflow and outflow have been adopted with the concrete eco-film reactor in order to realize sewage high-efficient purification and to arrive at the requirements of National Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002).Through experiments, the following regulations have been found in this paper.(1)The sequencing batch concrete eco-film reactor (SBCEFR) adopts its operation mode of intermittent inflow and outflow, its operation cycle includes 5 stages, i.e., stage of water (T1), stage of aeration (T2), stage of still sedimentation (T3), stage of drainage (T4) and stage of idle (T5). The duration of each stage was determined as T1 of 1.5h, T2 of 1.5h, T3 of 0.5h, T4 of 0.5h and T5 of 0.25h, and one operation cycle lasts 4.25h under the experimental conditions.(2) Biological film is easily cultivated on the concrete eco-films in SBCEFR. Usually, bio-film will be hanged well about 10 days after the reactor bio-film cultivating system is adopted to cultivate bio-film on the concrete eco-films.(3)Main factors which give impacts to sewage purification effort of SBCEFR include reaction duration of each stage, inflow COD load, inflow ammonia nitrogen load, inflow C/N, water temperature, amount of eco-films and so on.(4)Under the condition of the experiments, the average removal rate of COD and BOD5 is of 94.1% and 95.4% respectively, and those of ammonia nitrogen and total phosphorus is of 68.8% and 38.3% respectively. Main water quality index such as COD and BOD5 in outlet water from the reactor can reach the level 1 class A standard of the national standard GB18918-2002, NH3-N can close its level 1 class B standard but TP reaches its level 2 standard.(5)The removal rates of COD has not been impacted obviously and those of ammonia nitrogen has been affected little by the fluctuation of inlet pollutant load even if the inflow COD volume load fluctuates 7.3 times or the inflow ammonia nitrogen volume load waves about 1.6 times. It proves the fact that the reactor has strong ability of bearing shock pollutant load.(6) There exists alternative environment of aerobic and hypoxia status within the reactor due to the influence of operation mode. It provides good conditions for high efficient removal of organics, nitrogen and phosphorus. High efficient removal of organics, nitrogen and phosphorus is the result of comprehensive effect of dilution of obligated water in the reactor, anoxia hydrolysis, alternatives of aerobic reaction and anoxia reaction.The experimental results show that SBCEFR has characteristics of high efficiency and low cost, and is available for small and medium-sized wastewater treatment plants.
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