准好氧填埋场氮素形态变化及转化特性研究

Research on characteristics of variation and transformation of nitrogen forms in semi-aerobic landfill

通过实验室填埋柱模拟实验,考察了准好氧生物反应器填埋场稳定化过程中氮素的形态变化和转化特性.根据渗滤液水质及N2O气体浓度变化特性,将垃圾降解过程分为4个阶段,即初期（2~50d）、中期（52~138d）、后期（140~214d）和末期（216~262d）.研究了渗滤液中NH＋4-N、TKN、TN、有机氮（Org-N）、NO-2-N、NO-3-N及气体N2O在垃圾降解过程中的变化规律,并依据氮素的变化规律探讨了这4个阶段中氮素的转化途径.结果表明：初期氮的转化途径主要是氨化作用和反硝化作用;中期主要是氨化作用和同时硝化反硝化作用;后期和末期硝化作用强于反硝化作用.

A lab-scale semi-aerobic bioreactor landfill experiment is established to investigate the characteristics of variation and transformation of nitrogen forms during its stabilization. Four stages,namely,the initial stage（2~50d）,the middle stage（52~138d）,the third stage（140~214d）and the final stage（216~262d）are taken during the biodegradation of MSW according to the variation characteristics of leachate quality and N2 O concentration. The variation characteristics of NH＋ 4-N,TKN,TN,Org-N,NO-2-N and NO-3-N in leachate and N2 O in landfill gases are studied,and the nitrogen transformation pathways in fours stages are discussed based on the changing rule of different nitrogen forms.Some conclusions are drawn as follow：during the initial stage,nitrogen transformation approaches are mainly ammoniation and denitrification;during the middle stage,ammoniation and simultaneous nitrification denitrification are the main pathways;nitrification is stronger than denitrification during the third and final stages.