垃圾填埋场渗沥液击穿防渗系统的指示污染物研究

发布时间：2019-01-24 08:31

【摘要】：中国垃圾填埋场渗沥液中的污染物种类繁多,成分复杂,污染物击穿填埋场防渗系统,造成地下水以及土壤污染已成为填埋场环境安全问题中最为关注的问题之一。目前以什么标准判断击穿,以何种污染物作为指示污染物计算击穿时间并评价防渗系统的防污性能尚不明确。针对这一问题,以中国6个典型填埋场内代表性污染物的平均浓度为初始浓度,以中国相关环境标准中规定的各类污染物极限浓度作为污染浓度,建立污染物在复合防渗系统中的一维对流弥散有限元模型。通过计算各类污染物在填埋场防渗系统中的击穿规律和击穿时间发现,相比重金属和持久性有机污染物,有机污染物(COD)最早击穿防渗系统,有机污染物(COD)可作为判定击穿的指示污染物,击穿HDPE土工膜单层和双层复合垫层的时间分别为84.2 a和122.6 a;而击穿时间主要受污染物的初始浓度、规定的污染浓度和污染物的迁移弥散参数共同影响。这一结果可为填埋场防渗系统击穿时间的计算和防污性能的评价提供参考。
[Abstract]:There are many kinds of pollutants in leachate of landfills in China. The pollutants break through the landfill seepage control system and cause groundwater and soil pollution which has become one of the most concerned problems in landfill environmental safety. At present, it is not clear what standard is used to judge breakdown, which pollutant is used as indicator pollutant to calculate breakdown time and to evaluate anti-fouling performance of anti-seepage system. To solve this problem, the average concentration of representative pollutants in six typical landfills in China is taken as the initial concentration, and the limit concentration of various pollutants specified in the relevant environmental standards of China is taken as the pollution concentration. A one-dimensional convection dispersion finite element model of pollutants in composite seepage control system is established. By calculating the breakdown rule and breakdown time of various pollutants in landfill seepage control system, it is found that compared with heavy metals and persistent organic pollutants, organic pollutant (COD) is the first to break through the seepage control system. The organic pollutant (COD) can be used as an indicator pollutant to determine breakdown. The time of breakdown of HDPE geomembrane monolayer and double-layer composite cushion is 84.2a and 122.6 a, respectively. The breakdown time is mainly affected by the initial concentration of the pollutant, the prescribed concentration of the pollutant and the transport and dispersion parameters of the pollutant. The results can provide a reference for the calculation of breakdown time and the evaluation of antifouling performance of landfill seepage control system.
【作者单位】：河海大学环境学院;河海大学水文水资源学院;江苏省水利科学研究院;河海大学土木与交通学院;
【基金】：国家重点基础研究发展计划(“973”计划)项目(2012CB719804) 国家科技重大专项(2013ZX07113001) 科技基础设施建设计划—国家工程技术研究中心培育点项目(BM2013013)
【分类号】：X799.3

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