反硝化颗粒污泥在纳米零价铁胁迫下的性能恢复  

Performance Recoverability of Denitrifying Granular Sludge Under the Stressing Effect of Nanoscale Zero-valent Iron

作　　者：王翻翻[1] 钱飞跃[1,2,3] 沈耀良[1,2,3] 王建芳[1,2,3] 张月茹[1] 刘郭洵 

机构地区：[1]苏州科技大学环境科学与工程学院,苏州215009 [2]江苏省环境科学与工程重点实验室,苏州215009 [3]江苏省水处理技术与材料协同创新中心,苏州215009

出　　处：《环境科学》2016年第4期1478-1484,共7页Environmental Science

基　　金：国家自然科学基金项目(51308367);江苏省高校自然科学研究基金项目(15KJB610013);江苏高校优势学科建设工程项目;苏州科技学院研究生创新工程项目(SKCX14-019);江苏省高校大学生实践创新训练计划项目(201513985006Y)

摘　　要：为探明纳米零价铁(nZVI)对反硝化颗粒污泥(DGS)潜在的胁迫效应,本研究通过连续多批次实验,考察了经历n ZVI短期冲击后,DGS反硝化活性在不同C/N比条件下的恢复情况.结果表明,当nZVI投加量高于5 mg·L^(-1)时,DGS比反硝化速率(μ)会出现下降,对应的比反硝化抑制率(IR)与基质C/N比、nZVI投加量呈现正相关.当nZVI投加量达到100 mg·L^(-1)时,胞外蛋白与多糖含量均明显降低.此时,充足的外加碳源(C/N≥4)将有助于促进DGS反硝化活性的恢复和减少去除单位硝态氮所消耗的COD值.由Freundlich和Langmuir吸附等温线的拟合结果可知,基质C/N比越高,DGS对n ZVI的吸附能力就越强.在恢复期内,泥相中总铁含量(Qe)的持续削减为高C/N比条件下,DGS反硝化活性的提升创造了有利条件.当Qe降至0.4 mg·g^(-1)以下时,μ值可达到或接近对照组的水平.To explore the potential stressing effect of nanoscale zero-valent iron（ nZVI） on denitrifying granular sludge（ DGS）,the evolution of DGS denitrifying performance under different C / N ratios was investigated in this study,by carrying out batch tests of eight successive periods with the nZVI shock-loading. The results showed that the specific denitrification rate of μ value decreased when the nZVI dosage was higher than 5 mg·L^-1. Meanwhile,a positive correlation between the inhibition ratio（ IR） of μ value and substrate C / N ratios or nZVI dosage was observed. When the nZVI dosage reached 100 mg·L^-1,both extracellular protein and polysaccharides concentrations decreased obviously. It would be beneficial to promote the recovery of DGS denitrifying activity and reduce the COD demanding to remove unit mass of nitrate,by increasing external carbon source with C / N ratios of higher than 4. On the basis of Freundlich and Langmuir adsorption isotherms,when higher C / N ratio was provided,stronger bioadsorption of nZVI would be achieved. During the recovery period,a significant improvement of DGS denitrifying performance under the high C / N ratio was expected,due to the continuous washout of total iron in sludge phase（ Qe）,while the μ value would reach or approach the one of the control group when Qewas lower than 0. 4 mg·g^-1.

关 键 词：反硝化颗粒污泥 纳米零价铁 C/N比 活性恢复 吸附 

分 类 号：X703.1[环境科学与工程—环境工程]