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Fly ash is a coal-fired power plant emissions, solid waste, if disposed of improperly, not only will cause secondary pollution to the environment, but also a serious waste of resources. Currently, the main application of fly ash ways directly as building materials or firing ceramsite used as construction aggregate. Lytag Biological Aerated Filter wastewater treatment become a hot research at home and abroad in recent years. However, these ceramsite fly ash and clay depletion of resources in this category must be added. Therefore, the research and development of fly ash, the ceramsite imperative to meet the requirements of Biological Aerated Filter. In this paper, fly ash as the main raw material, add gangue as a pore-forming agent, mixed into a ball, high-temperature calcination process preparation of the ceramic filter, the effects of the calcination temperature, holding time and the ratio of raw materials (coal gangue content) the ceramsite performance, combined with orthogonal experiment to determine the preparation of the ceramsite the best process conditions; applied to biological aerated filter reactor will be obtained in accordance with the optimum conditions haydite processed sewage of a small pilot study, the removal of pollutants by examining the performance of fly ash ceramic filter in biological wastewater treatment. In accordance with national standards \and for the evaluation of the the ceramsite performance indicators, by single factor test and orthogonal test to determine the best preparation Lytag process conditions: calcination temperature 1050 ° C, 5% of the holding time of 10min, gangue content. Obtained under optimum conditions Lytag indicators: density 2.1286g/cm 3 the bulk density 0.9817g/cm 3 , apparent density 1.6965g/cm 3 , specific surface area 1.6012 × 10 4 cm 2 / g, porosity 42.13%, 0.25% clay content, Hydrochloric acid soluble rate of 1.46%, broken rate and the wear rate of 2.96%. The scanning electron microscope analysis shows that the rough surface Lytag pore structure and a large number of large holes, conducive attached to the growth of micro-organisms, is an excellent microbial carrier. Obtained under optimum conditions Lytag filter, used as a biological aerated filter treatment of municipal sewage. The reactor uses method of vaccination hanging film to start, start-up time of 11d. Were investigated during start-up and stable operation during biological aerated filter reactor removal efficiency of COD, NH 3 -N, total phosphorus, SS. During startup, with the running time of the extension of the reactor effluent COD decreasing removal rate gradually increased; increased effluent total phosphorus removal rate decreases; effluent NH3-N concentration decreases, the removal rate of l high, and then stabilized. During stable operation, the hydraulic load of the reactor by 0.15m3 / (m2? H) gradually increased to 0.30m 3 / (m 2 · H), 0.45m 3 / (m 2 · h) and 0.60m 3 / (m 2 · h), investigated changes in the hydraulic loading of pollutant removal effect. At the same time, the filter layer at different heights COD and NH 3 - N removal effect. Finally, comparing the performance of fly ash ceramsite and commodity Ceramisite, in physical and biological wastewater treatment performance. The analysis showed that the fly ash and coal gangue raw Ceramisite can achieve good economic, social and environmental benefits.
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