...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Enhanced Reductive Dechlorination of Tetrachloroethene Dense Nonaqueous Phase Liquid with EVO and Mg(OH)_2
【24h】

Enhanced Reductive Dechlorination of Tetrachloroethene Dense Nonaqueous Phase Liquid with EVO and Mg(OH)_2

机译：EVO和Mg（OH）_2增强四氯乙烯致密非水相液体的还原还原脱氯

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In situ treatment of dense nonaqueous phase liquids (DNAPL) by enhanced reductive dechlorination (ERD) can be limited by contaminant toxicity, low pH, and challenges in effectively delivering electron donor. Flushing emulsified vegetable oil (EVO), colloidal Mg(OH)_2 buffer, and a bioaugmentation culture (BC) through a zone containing neat tetrachloroethene (PCE) was effective in reducing contaminant toxicity, limiting pH declines, and accelerating bioenhanced dissolution of the DNAPL. In the effluent of porous media columns with little fine material, PCE concentrations reached a maximum of 40-50 times PCE aqueous solubility in water, demonstrating NAPL PCE was distributed throughout the 1.5 m column length. In a column treated with only EVO+BC, reductive dechlorination was limited. However, a single injection of EVO+Mg(OH)_2+BC was effective in reducing PCE to below detection for over 400 days with a large increase in Cl~- and dichloroethene (DCE), accelerating bioenhanced DNAPL dissolution. Dechlorination rates gradually increased over time with the rate of total ethene (TE) release from the Mg(OH)_2+EVO+BC column reaching 5-6 times the TE release rate from the EVO+BC column. The accelerated dechlorination was likely due to both Mg(OH), addition which limited pH declines from HC1, volatile fatty acids (VFAs), and inorganic carbon (IC) production, and formation of a mixed PCE-vegetable oil NAPL which provided a readily accessible electron donor, resulting in rapid PCE degradation with reduced PCE toxicity.
机译：通过增强的还原性脱氯（ERD）原位处理稠密非水相液体（DNAPL）可能会受到污染物毒性，低pH值以及有效输送电子供体的挑战的限制。通过包含纯四氯乙烯（PCE）的区域冲洗乳化植物油（EVO），胶体Mg（OH）_2缓冲液和生物强化培养物（BC）可有效减少污染物毒性，限制pH值下降并加速DNAPL的生物增强溶解。在几乎没有细料的多孔介质色谱柱流出物中，PCE浓度最高达到PCE在水中的40-50倍的水溶解度，这表明NAPL PCE分布在整个1.5 m色谱柱长度上。在仅用EVO + BC处理的色谱柱中，还原脱氯受到限制。但是，单次注射EVO + Mg（OH）_2 + BC可以有效地将PCE降至检测不到的水平超过400天，其中Cl-和二氯乙烯（DCE）大量增加，从而加速了DNAPL的生物增强溶解。随着Mg（OH）_2 + EVO + BC色谱柱的总乙烯（TE）释放速率达到EVO + BC色谱柱的TE释放速率的5-6倍，脱氯速率随时间逐渐增加。加速脱氯的原因可能是由于Mg（OH），有限的HCl，挥发性脂肪酸（VFA）和无机碳（IC）产生的pH下降以及形成PCE-植物油NAPL的混合，这使得脱氯变得容易。可利用的电子供体，导致PCE快速降解，降低了PCE毒性。

著录项

  • 来源
    《Environmental Science & Technology》 |2014年第1期|624-631|共8页
  • 作者

    Kirsten M. Hiortdahl; Robert C. Borden;

  • 作者单位

    Department of Civil, Construction and Environmental Engineering, North Carolina State University, Raleigh, North Carolina 27695,United States;

    Department of Civil, Construction and Environmental Engineering, North Carolina State University, Raleigh, North Carolina 27695,United States,Solutions-IES, Inc., 1101 Nowell Road, Raleigh, North Carolina 27607, United States;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号