摘要
尾矿库用来堆积矿产资源开采过程中产生的矿物废料,其重金属种类多,含量高,储存量大,影响范围广。尾矿长期堆放严重污染库区水生态环境,是目前重金属污染的主要来源之一。以德兴铜矿5号尾矿库为背景,建立了简化的分层土柱模型,研究双组分重金属离子在成层土壤中的运移规律。选择常见的铜、铁离子为污染物,通过测定不同深度处渗滤液中金属离子质量浓度,观测其在分层土柱中的迁移情况。结果表明：土柱中同一深度铜、铁离子质量浓度随时间延长而升高,初始阶段增速较大后逐渐降低;在垂向上,距离污染源越远离子质量浓度越低,且这种关系能用对数函数描述。黏土层对金属离子的迁移能起到有效的阻滞作用,试验结束时对铜、铁离子的阻滞净化效率分别可达88.98%、93.04%,但长期的渗透作用终会使污染物穿透黏土层,并更快地向下发展。双组分重金属离子共存时,迁移过程中金属离子之间会相互影响,与单个铜离子的运移对比,铁离子的加入使渗滤液中铜离子的质量浓度升高,且随着试验进行铜离子质量浓度升高幅度越来越大。铁离子的加入使30 cm深处渗滤液在第7 d时铜离子质量浓度增加了1.13%,第70 d时增大幅度达到8.62%。尝试性提出了防渗层阻滞净化效率的估算方法,反映防渗层工作状态及估计其有效使用时间,为尾矿库重金属污染预防和治理提供参考。
In this paper,the author intends to make an experiment based on No.5 tailing pond of Dexing copper mine as a case study sample to investigate the migration process of the heavy metal ions of the two-components in the stratified soils in the mine so as to establish a generalized layered soil column model. Since the tailing ponds are used to pile up the mineral slags left over in the mining process of the mineral resources,the copper and iron ions have been chosen as pollutants in the stratified soil column to be treated. As a matter of fact,it is one of the main sources of heavy metal pollutants, which are characterized by numerous kinds of heavy metals with the large amount of storage bringing about a wide range of impacts. Since long-term storage of tailing has been seriously polluting the water ecological environment in the reservoir area,the content concentration rates of the said ions have been increasing with time at the same depth of the soil column. On the other hand,the growing rates of the content concentration have been gradually decreasing. Moreover,in the vertical direction,the ion concentration rate has become gradually lower at the farther location away from the source of the contamination.Thus,the concentration rate of the heavy metal ions has become gradually decreasing in the unit soil thickness,and,in turn,the above said relation can be properly described by using the logarithmic function. What is more,since the clay layer has an effective blockade effect on the migration of the heavy metal ions,it has been found that in a period of 70 days,the blocking and purifying effect and efficiency of the copper and iron ions has been found going up as high as 88. 98% and 93. 04%. Thus,the longterm infiltration can eventually be expected to cause the pollutants to penetrate into the clay layer and protrude faster. Besides,since the two heavy metal ions components are coexisting in a mixed way,the concentration of the weakly competitive ions may increase in the leachate. Therefore,the addition of ferric io
作者
詹美礼
李智涵
杨旭
盛金昌
罗玉龙
徐建荣
李柯雅
ZHAN Mei-li;LI Zhi-han;YANG Xu;SHENG Jin-chang;LUO Yu-long;XU Jian-rong;LI Ke-ya(College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China;Chinese Electric Power Construction Group East China Investigation and Design Institute, Hangzhou 310014, China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2018年第3期1133-1139,共7页
Journal of Safety and Environment
基金
国家自然科学基金项目(51579078,51474204,51679070)
关键词
环境工程学
离子运移
重金属离子
双组分
分层土壤
environmental engineering
ion migration
heavy metal ions
two components
stratified soils
