| Shortage of water resource is an important restricting-factor of the economy and society development in China, and a great deal of municipal sewage directly draining into water body without any treatment or with little treatment is a main cause why the quality of water environment has been deteriorating as a whole. So it is urgent to research and develop simple, high-efficient, low-consumptive treatment techniques for municipal sewage correspond to the situation of China. Aerated biofilter is one of the important technical approaches to resolve the problem. The study focuses on municipal sewage treatment using an aerobic-anoxic integrative biological filter in which granular ceramics media is used. It includes start-up of the filter under condition of natural temperature, and performance of the filter treating municipal sewage under some hydraulic load(organic volume load), and the effects of the parameters : ratio of air and water and temperature correlated to the filter.In the experiment the influent is manually made up. The results demonstrate: It takes about 11d to complete the start-up under the condition of 24—28℃ with the sludge of aeration tank as seed. When the COD in influent varies between 300— 400mg/L and the NH3—N in influent varies between 40—55mg/L, and HRT of the aerobic zone is more than 0.5h, and HRT of the anoxic zone is more than 0.44h, the ratio of air and water is more than 5, COD and NH3—N of the effluent can reach 70mg/L and 25 mg/L. The removal ratio can be enhanced with increase of ratio of air and water. The removal ratio can be reduced with decrease of temperature. Nitrification mainly occurs in aerobic area and denitrification primarily occurs in anoxic area. By analyzing the height of the biological filter, it exists the optimum height in the biological filter.
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