沸石与生物沸石薄层覆盖技术削减富营养化景观水体氮比较研究

以扬州古运河河水和表层沉积物为研究对象，实验室静态模拟实验比较研究了沸石与生物沸石（即附着高效异养硝化菌和好氧反硝化菌的沸石）薄层覆盖削减富营养化景观水体氮效果，考察了生物沸石薄层覆盖削减氮可行性，探讨了生物沸石薄层覆盖削减氮的机理和影响因素。实验结果表明，当实验历时21d时，2kg／m^2（2mm厚）的沸石和生物沸石覆盖对上覆水体TN的削减率分别为36．92％和60．41％，生物沸石比沸石对TN削减率提高了23．48％，高效菌的生物脱氮作用明显；21d后生物沸石覆盖对TN的削减率维持在60％～75％，但生物沸石相对于沸石削减氮的效果有降低趋势。实验后期碳源不足是影响高效菌生物脱氮的主要影响因素。可见，生物沸石薄层覆盖削减富营养化景观水体氮是可行的，但需要进一步研究强化高效反硝化细菌适应能力方法。

Comparative investigation of zeolite and biozeolite thin-layer capping for nitrogen reduction from eutrophic landscape wa~er body

Taking the overlying water and surface sediment from the ancient canal in Yangzhou City as the research objects, the comparative investigation of zeolite and biozeolite （i. e. zeolite attaching isolated hetero- trophic nitrifiers and aerobic denitrifier） thin-layer capping for nitrogen reduction were examined through labora- tory scale incubation experiments that lasted 81 days. The feasibility of nitrogen reduction using biozeolite cap- ping was estimated, and then the mechanisms and effect factors were analyzed. The results showed that, when the experiments lasted 21 days, the reduction efficieneies of total nitrogen （TN） using zeolite and biozeolite cap- ping of dose rate of 2 kg/m2 （the thick of 2 mm） were 36.92% and 60.41% , respectively. The reduction effi- ciency of TN by biozeolite capping was improved by 23.48% than that by zeolite capping, indicating that the effect of biological denitrification of high-efficiency bacteria was significant. After 21 days, the reduction efficien- cies of TN biozeolite capping could maintain at 60% - 75%. However, compared with zeolite capping, the re- duction effieiencies of TN using biozeolite capping had the decreased trend. In the final stage of the experiments, shortage of carbon source was the main influencing factor in affecting biological denitrification of high-efficiency bacteria. Therefore, nitrogen reduction in eutrophic landscape river using biozeolite capping is feasible. Howev- er, it is urgent to further strengthen the adaptability of aerobic denitrifiers.