摘要
采用砂柱装置,在实验室研究了自养微生物和异养微生物2种生物反硝化方法对地下水中硝酸盐的去除效果。自养反硝化反应在以硫作为电子供体的硫/石灰石/细沙反应柱中进行,异养反硝化反应在石灰石/细沙反应柱中进行,进水增加乙醇作为外加碳源。实验结果用以比较2种反硝化方法在硝酸盐去除率、微生物反应动力学和反应产物三者的异同。结果表明,自养反硝化反应中NO3--N去除率达95.4%,异养反硝化反应去除率可达99.3%;分别与Monod微生物0级、1/2级和1级反应动力学方程进行拟合,2种反硝化反应均符合1/2级微生物反应动力学,适合用1/2级微生物反应方程描述;在反应结束阶段,自养反硝化主要反应产物SO42-出水浓度低于250mg/L,异养反硝化副产物CH3OO-易成为二次污染源,异养反硝化的反硝化速率明显高于自养反硝化反应。
Aquifer sand column devices were used for the experiment of autotrophic microorganisms and heterotrophic microorganism biological denitrification of nitrate removal.Denitrification reaction was done in the sulfur/limestone/sand reaction column with sulfur as an electron donor,while heterotrophic denitrification in the limestone/sand reaction column with ethanol as external carbon source.The two methods were compared with the aspect of nitrate removal efficiency,microbial kinetics and reaction product.Results showed that both methods were applicable to the removal of nitrate,with autotrophic biological denitrification removal rate as 95.4% and heterophic biological removal rate as 99.3%.Fitting with the Monod equation of zero-order,1/2 order and first order,the reactions satisfied 1/2 order degradation reaction and the reaction products were SO42-and CH3COO respectively for autotrophic denitrification and heterophic denitrification.
出处
《环境科学与技术》
CAS
CSCD
北大核心
2013年第5期108-111,146,共5页
Environmental Science & Technology
基金
国家自然科学基金项目(41172229)
国家科技支撑计划项目课题(2012BAC16B02)
广西建筑新能源与节能重点实验室开放基金(11-031-21-4)
关键词
地下水
硝酸盐污染
自养反硝化
异养反硝化
groundwater
nitrate pollution
autotrophic denitrification
heterophic denitrification
