摘要
城市河道底泥致黑臭多污染物的同步耦合去除是当前研究的热点。为实现河道底泥致黑臭污染物的同步去除,采用电动修复技术开展了氧化去除黑臭底泥硫化物、亚铁和氨氮等还原性污染物的室内模拟实验。实验结果表明:在单向通电(1.5 V·cm-1)10 d后,阳极区对底泥硫化物(AVS)、亚铁有明显的氧化效果,去除率分别达到59.51%和79.41%,但阴极的去除效果不明显;阳极区和阴极区均对间隙水氨氮有明显的去除效果,去除率分别为56.5%和73.9%。在氧化过程中,阳极和阴极出现明显的酸化和碱化现象,而这种两极酸碱化可以通过周期性切换电极的方式加以避免。在电极切换频率为1、2.5和5 d·次-1时,对黑臭物质的氧化效果差别明显;在切换频率为5 d·次-1时,对硫化物、亚铁氧化去除效果最好;在切换频率为2.5 d·次-1时,对氨氮去除效果最佳。硫化物、亚铁、氨氮最大去除率可分别达到76.19%,72.48%和88.57%。由此可见,电动修复可以同步去除底泥中的致黑臭污染物质,改善水体水质,但其去除率有待进一步优化提高。
Synchronous removal of multi-pollutants in black and odorous sediment in urban rivers is a hot research topic nowadays. To achieve synchronous removal of multi-pollutants in black and odorous sediment,the indoor simulation experiments of oxidation removing the reductive pollutants in black and odorous sediment,such as sulfide, ferrous and ammonia nitrogen, were conducted with electrickinetic remediation technology. The results showed that after 10 days treatment by one-way electrode electrolysis(1.5 V·cm-1), acidic volatile sulfide(AVS) and ferrous iron could be obviously oxidized in the anode sediment area, with the removal rates of59.51% and 79.41%, respectively;but their removal effects in the cathode area was not significant. In addition,the ammonia nitrogen concentrations in interstitial water could be significantly reduced in both anode and cathode area, and the corresponding removal rates were 56.5% and 73.9%, respectively. However, during the oxidation process, obvious acidification in anode area and alkalinization in cathode area occurred, which could be avoided by periodically switching the electrodes. At the electrode switching frequencies of 1-, 2.5-, and 5-day per cycle, the oxidation efficiencies of black-odorous pollutants were significantly different during the electrokinetic remediation. In addition, the optimized electrode switching frequency for sulfide and ferrous iron removal was 5-day per cycle, while for ammonia nitrogen removal was 2.5-day per cycle. The maximum removal rates of sulfide, ferrous iron and ammonia nitrogen could reach 76.19%, 72.48% and 88.57%,respectively. The above findings indicated that electrickinetic remediation technology could simultaneously remove multi-pollutants in the black-odorous sediments and improve the water quality, but the corresponding removal efficiencies may require further improvement.
作者
赖江钿
程明双
余光伟
高诗婷
吴佳丽
周丽鸿
张艳
何静仪
LAI Jiangtian;CHENG Mingshuang;YU Guangwei;GAO Shiting;WU Jiali;ZHOU Lihong;ZHANG Yan;HE Jingyi(College of Resources and Environment,South China Agricultural University,Guangzhou 510642,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2020年第7期1779-1788,共10页
Chinese Journal of Environmental Engineering
基金
广东省科技计划项目(2014A020216034,2011B030800019)。
关键词
河道黑臭底泥
电动修复
硫化物
亚铁
氨氮
氧化
black-odorous sediments in river
electrokinetic remediation
sulfide
ferrous
ammonia nitrogen
oxidation
作者简介
第一作者:赖江钿(1994—),男,硕士研究生。研究方向:城市河道原位黑臭治理。E-mail:907968094@qq.com;通信作者:余光伟(1978—),男,博士,副教授。研究方向:城市河道原位黑臭治理。E-mail:yuguangwei@scau.edu.cn。
