贝壳与球形塑料填料曝气生物滤池的硝化特性比较

采用曝气生物滤池．考察贝壳与球形塑料填料的硝化特性变化情况．研究结果表明，贝壳填料曝气生物滤池因贝壳中CaCO3的溶解为硝化反应提供碱度．硝化率保持在较高的水平．而球形塑料填料曝气生物滤池因碱度不足．硝化率处于较低的水平．贝壳填料曝气生物滤池内pH值沿池深方向呈逐渐升高趋势．而球形塑料填料滤池则相反．外加碱度可以提高曝气生物滤池的氨氮去除率．贝壳填料的曝气生物滤池相比于传统的塑料填料曝气生物滤池具有明显的硝化处理优势．

Comparison of Nitrification Behavior Between Shell and Plastics Ball Carrier in Aerated Biofilter

Most of studies on biological ammonia treatment have been carried out so far under the condition of pH higher than 7 by adding NaOH or Na_2CO_3 to supply the sufficient alkalinity.Shell,as fishery product waste,contains large amount of CaCO_3.In the present work, two aerated bio-filters packed with the biomass carrier of shell and plastics ball respectively were evaluated simultaneously,and the transient behavior of nitrification efficiency were compared under the different influent pH values and ammonia loading.The results demonstrated that the bio-filter packed with shell presented higher ammonia removal efficiency than that with plastics ball by supplying alkalinity to raise the pH value.In shell packing bio-filter,the nitrification activity of nitrifying bacteria was less to be inhibited even though pH value in influent was at relatively low level,indicating that shell could supply alkalinity sufficiently by dissolving CaCO_3 at low pH condition.By contract,in plastics ball packing bio-filter,the nitrification activity was inhibited severely due to the lack of alkalinity supply at low influent pH value,resulting in a gradually decrease in nitrification efficiency as ammonia concentration increased in influent.Consequently,shell appears more superior to traditional plastics ball when using as biomass carrier in aerated bio-filter for ammonia removal at low pH value and high ammonia loading in influent.