摘要
硝酸盐(NO_(3)^(−)-N)污染已成为最重要的水质问题之一,硫(S0)自养反硝化工艺以低成本、污泥产量少的优势受到广泛关注,为了进一步提高脱氮效率,该研究考察了铁介质对S0自养反硝化工艺脱氮速率,脱氮效率及微生物群落结构的影响。通过批次实验,确定了纳米零价铁(Fe0)可强化硫自养反硝化脱氮性能,最佳投加量为0.48 g·L^(−1),相应NO_(3)^(−)-N的去除速率为8.04 mg·(L·d)^(−1),为对照组的1.87倍。NO_(3)^(−)-N去除过程符合一级动力学模型,反应速率常数是对照组的4.46倍。Fe0主要通过刺激微生物胞外聚合物分泌,提高电子传递活性,并伴随化学作用进而强化脱氮。连续运行实验结果表明,连续添加0.48 g·L^(−1)Fe0的S0自养反硝化工艺系统稳定性增强,当NO_(3)^(−)-N进水负荷由0.14kg·(m^(3)·d)^(−1)提高到0.32 kg·(m^(3)·d)−1时,出水总氮(TN)稳定达到《地表水环境质量标准》(GB 3838-2022)的V类水标准(<2 mg·L^(−1))所需的时间比不添加Fe0系统至少快5 d。微生物群落分析结果表明,连续添加Fe0增加了优势自养反硝化菌群(Thiobacillus、Sulfurimonas、Ferritrophicum)的丰度。以上研究结果可为Fe0强化S0自养反硝化工艺脱氮性能提供数据支持。
Nitrate(NO_(3)^(−)-N)pollution has become one of the most significant water quality issues.Sulfur(S0)autotrophic denitrification processes are gaining widespread attention due to their low cost and minimal sludge production.To further enhance nitrogen removal efficiency,the impacts of iron media on the denitrification rate,denitrification efficiency,and microbial community structure in S0 autotrophic denitrification processes were investigated.Through batch experiments,it was determined that nano zero-valent iron(Fe0)could enhance the nitrogen removal performance of sulfur autotrophic denitrification,with a corresponding NO_(3)^(−)-N removal rate of 8.04 mg·(L·d)−1 at the optimal dosage of 0.48 g·L^(−1),which was 1.87 times that of the control group.The NO_(3)^(−)-N removal process followed a first-order kinetic model,with the reaction rate constant being 4.46 times that of the control group.Fe0 enhanced nitrogen removal mainly through stimulating the secretion of extracellular polymeric substances in microorganisms,increase the activity of electron transfer and accompanied chemical interactions.Continuous operation experiments revealed that the stability of the S0 autotrophic denitrification system was enhanced with the continuous addition of 0.48 g·L^(−1)Fe0.When the influent load of NO_(3)^(−)-N increased from 0.14 kg·(m^(3)·d)−1 to 0.32 kg·(m^(3)·d)−1,the effluent total nitrogen(TN)consistently met the Class V water quality standards(<2 mg·L^(−1))according to the"Surface Water Environmental Quality Standards"(GB3838-2022),achieving this at least 5 days faster than the system without Fe0 addition.Microbial community analysis showed that the continuous addition of Fe0 increased the abundance of dominant autotrophic denitrifying bacterial groups(such as Thiobacillus,Sulfurimonas,Ferritrophicum).The research findings can provide a data support for the enhancement of nitrogen removal performance in S0 autotrophic denitrification processes with Fe0.
作者
刘柏利
邢琳琼
王亚静
刘艳芳
陈静
钟雨
LIU Baili;XING Linqiong;WANG Yajing;LIU Yanfang;CHEN Jing;ZHONG Yu(College of Environmental Science and Engineering,Hebei University of Science and Technology,Shijiazhuang 050018,China;Hebei Key Laboratory of Pollution Prevention Biotechnology,Shijiazhuang 050033,China;Shijiazhuang Qiaodong sewage treatment plant,Shijiazhuang 051430,China)
出处
《环境工程学报》
北大核心
2025年第3期697-708,共12页
Chinese Journal of Environmental Engineering
基金
河北省重点研发项目(21373602D)。
关键词
硫自养反硝化
脱氮速率
纳米零价铁
电子传递系统活性
微生物群落
sulfur autotrophic denitrification
denitrification rate
nano zero-valent iron
activity of electron transport system
microbial community
作者简介
第一作者:刘柏利(2000-),女,硕士研究生,研究方向为水环境污染防治,810404139@qq.com;通信作者:刘艳芳(1984-),女,博士,副教授,研究方向为水环境污染防治,lyftry@126.com。
