摘要
通过河岸渗滤作用(riverbankfiltration,RBF)诱发河水的补给,增大地下水的允许开采量可以满足更多居民生活饮用水需求.受人类活动的影响,河流等地表水体遭受苯胺污染,可能通过RBF进入地下水,以致饮用该地下水存在健康风险.为研究反硝化条件下,苯胺在RBF中的转化,采集渭河河床沉积物及沿岸地下水含水层的含水介质,装置土柱,进行土柱动态模拟实验.经过153d的实验研究发现,利用苯胺对RBF中土著反硝化微生物进行驯化,大约经过37d菌种完全适应.具有该菌种的RBF系统,对苯胺具有巨大降解能力,在NO3--N约为23.0mg/L的条件下,RBF系统可使40、80甚至400mg/L浓度的苯胺100%降解,矿化率分别达97.99%、91.39%与75.30%.反硝化条件下,苯胺在RBF中的降解仅有少部分经过脱氨作用,绝大部分与腐殖质以共价键形式形成耦合物,该耦合物更易为微生物降解,且降解过程中不产生对研究环境微生物有毒的中间产物,可实现反硝化条件下RBF中苯胺的连续降解.
Aniline can enter the environment from many industries, and has been detected in surface water including river water. For many cities in north China such as Xi'an, Lanzhou and Harbin, the drinking water is produced from groundwater recharged by river water through riverbank filtration (RBF). Aniline is a refractory organic pollutant and harmful to humans. So its degradation and mechanism have received much attention. In this paper, soil columns containing sediment and aquifer media were collected from the Weibe riverbed and its bank, and were used to research the characteristics of aniline degradation in the riverbank filtration process under denitrification conditions. The results indicate that all aniline could be degraded by habituated indigenous microorganisms, and even mostly mineralized under denitrification conditions, but the degradation had a long lag period. A minority of aniline degradation must involve deamination, while the majority undergoes covalent binding with humic substances to form complexes. The complexes are degraded easily and even mineralized. During the degradation, no intermediates were harmful to denitrifiers. Therefore, under denitrification conditions, aniline has the potential to biodegrade in RBF and the potential lasts for long time, and this has not been monitored in the groundwater along the polluted river. During the 153 d testing process, the nitrate-nitrogen concentration was about 23.0 mg/L, and the aniline concentration was 40, 80 and 400 mg/L at 0-74 d, 75-105 d and 106-153 d respectively in infiltrating water. Indigenous microorganisms pass a lag period of 37 d, and grow on aniline as the source of carbon in the RBF under denitrification conditions. Aniline concentration in leachate is lower than the detected limits, so its removal rate was 100%. TOC removal rates were 97. 99 %, 91.39 % and 75.30 % for 40, 80 and 400 mg/L aniline concentrations respectively, based on TOC monitored infiltrating water and leachate.
出处
《地球科学(中国地质大学学报)》
EI
CAS
CSCD
北大核心
2006年第2期273-278,共6页
Earth Science-Journal of China University of Geosciences
基金
国家自然科学基金项目(No.40472127)
西北工业大学"英才计划"项目(2002).
关键词
反硝化条件
苯胺
河岸渗滤过程
厌氧转化
denitrification condition
aniline
riverbank filtration
anaerobic bio-translation.