生物沸石滤池去除微污染水源水中氨氮的挂膜启动

对沸石滤料生物滤池处理微污染水源水中低浓度氨氮的挂膜启动性能进行了研究。试验结果表明，挂膜过程可以根据氨氮、亚硝酸盐氮、硝酸盐氮浓度的变化分为三个阶段：初期沸石发挥本身对铵离子的吸附交换性能，氨氮去除率达88％以上；中期开始出现生物硝化作用，亚硝酸盐积累明显，硝酸盐出水浓度不稳定，氨氮去除率稳定，但下降至65％左右；后期硝化反应稳定进行，亚硝酸盐迅速转化为硝酸盐，氨氮去除率稳定在60％以上。生物沸石滤池挂膜同时应考察亚硝酸盐氮、硝酸盐氮浓度变化，在出水亚硝酸氮明显积累后又稳定降低，且硝酸盐氮稳定积累时方可认为挂膜成功。进出水pH值的变化可以指示硝化反应的进行程度和生物膜形成阶段。

Start-up of biological zeolite filter for removing ammonia nitrogen from contaminated source water

A biological zeolite filter was used to remove ammonia nitrogen with a low concentration from contaminated source water, and the process of start-up was carried out. The results showed the whole start-up period could be divided into three different parts, according to the variation of ammonia nitrogen, nitrite nitrogen and nitrate nitrogen. During the early stages, ion exchange was the major contributor to removal of ammonia nitrogen, and the removal rate was over 88%. Then the accumulation of nitrite nitrogen became apparent, the concentration of nitrate nitrogen fluctuated, the removal rate of ammonia nitrogen was about 65%. The nitrification reaction played the main role in the end, and nitrite nitrogen transformed to nitrate nitrogen rapidly. The removal rate of ammonia nitrogen kept above 60%. When nitrite nitrogen became reducing after a short period of accumulation as well as nitrate nitrogen steadily increasing, the start-up process of biological zeolite filter was finished. The pH in inflow and outflow water could be an indicator for nitrification reaction and the biofilm formation.