曝气生物滤池不同填料处理河道污水的效果

Efficiency comparison of biological aerated filter in the treatment of river sewage by using different kinds of fillers

曝气生物滤池处理河道污水,具有容积负荷大、处理效率高,占地面积小的特点,但除磷效果差。为了提高曝气生物滤池除磷效果和去除COD、NH3-N和SS的能力,本文利用贝壳、珊瑚和经过盐酸处理的铝硅酸盐作为曝气生物滤池的填料来处理河道污水.试验结果表明:在pH为中性的条件下,贝壳和珊瑚填料不能去除河道污水的磷酸盐,但经过盐酸处理后的铝硅酸盐填料对河道污水磷酸盐的去除率可达到52.19%,与传统处理方法相比,去除率提高了30%以上;贝壳填料对COD、NH3-N和SS的去除率分别为52.73%、36.75%、53.04%,珊瑚填料去除率分别为57.29%、33.44%、51.03%,经过盐酸处理的铝硅酸盐填料去除率分别为49.29%、33.20%、64.94%;珊瑚填料处理COD效果最好,去除率达到57.29%,这与该填料具有较大的比表面有关;贝壳填料去除NH3-N效果最好,达到36.75%,但与珊瑚填料和铝硅酸盐填料相比,差异不大,最大极差仅3.55%;铝硅酸盐填料去除SS的效果最好,达到64.94%,这可能与其颗粒小,比较致密有关.综合比较各种填料处理PO43-、COD、NH3-N和SS的能力,采用经过盐酸处理铝硅酸盐填料作为曝气生物滤池处理河道污水的填料是适宜的,其最佳水力停留时间为4h。

Biological aerated filter has the advantages of large loading capacity, high efficiency and small area in treating the river sewage, but is poor in the phosphorus removal. In order to improve the removal efficiency of phosphorus as well as the removal capacity of COD, NH3-N and SS, the river sewage was treated by biological aerated filter with three kinds of fillers, the shell, the coral, and the aluminum silicate after the hydrochloric acid treatment. Results shown that the phosphate in the river sewage could not be removed by the shell and the coral under the neutral conditions. However, the removal efficiency of phosphate was high as 52.19% after treating by the aluminum silicate fillers, with the removal rate increased by 30% or more when compared with the traditional method. This is because the major cations, such as Ca^2＋, Mg^2＋, Fe^3＋and Al^3＋ can be released from the aluminum silicate after the treatment of hydrochloric acid and then take part in the reaction of phosphate precipitation with the phosphate in the river sewage. The removal rates of COD, NH3-N and SS were 52.73%, 36.75% and 53.04%, respectively when using the shell as fillers, while that of the coral fillers were 57.29%, 33.44% and 51.03%, and that of the aluminum silicate fillers were 49.29%, 33.20% and 64.94%, respectively. The coral fillers had the highest removal rate of COD （57.29%）, which was related to the larger surface area of the fill- ers. The removal rate of NH3-N treated by the shell fillers was the highest （36.75%）, but there were no significant differences among the three fillers with the largest range less than 3.55%. The removal efficiency of SS treated by aluminum silicate fillers was the best in these three fillers with the removal rate of 64.94%, which might be due to the small particles and high density of the fillers. When considering the overall removal efficiency of PO4^3-, COD, NH3-N and SS, the aluminum silicate filler treated by the hydrochloric acid is more suitable to be the filler of biological aerated filter than the other two fillers in treating the river sewage, and the optimum hydraulic retention time was 4 h.