焦作矿区土壤对煤矸石中污染组分的吸附解吸试验  

Adsorption-desorption Behaviors of Pollutants from Coal Waste Rock on Soil in Jiaozuo Mine Field

作　　者：郭慧霞 杨建[2] 王心义[3] 郑海亮[2] 

机构地区：[1]焦作市环境科学研究所,河南焦作454000 [2]环境模拟与污染控制国家重点实验室/北京师范大学环境学院,北京100875 [3]河南理工大学,河南焦作454000

出　　处：《农业环境科学学报》2008年第1期194-199,共6页Journal of Agro-Environment Science

基　　金：河南省科学技术成果(9412006R0597);河南理工大学博士基金

摘　　要：以焦作矿区煤矸石和土壤为研究对象,进行室内模拟淋滤实验,检测淋出液中SO42-、Cl-、总硬度、Cr、Pb、Zn、Mn、Cu、Cd等污染组分的含量以及pH、电导率,分析研究煤矸石在淋滤作用下污染组分的溶出规律以及土壤对污染组分的吸附解吸。结果表明,焦作矿区煤矸石淋出液呈中性偏弱碱性,SO42-、总硬度、Zn、Mn等组分已经出现超标,Cr、Pb、Cu、Cd则未检出;在淋滤实验前期,风化煤矸石淋出液中的污染组分含量要高于新鲜煤矸石淋出液中的含量,土壤对污染组分有很大的吸附能力,约50%的污染组分被吸附;随着淋滤的进行,煤矸石中污染组分随水淋出的含量迅速下降并逐渐稳定下来,此时由于低浓度淋滤液进入土壤,使土壤中发生了污染组分的解吸,导致淋滤液中污染组分含量升高;土壤对污染组分的吸附解析与pH值、土壤组成类型、土壤中污染物含量、土壤的吸附容量、煤矸石淋出液中污染物浓度等有关。A series of leaching experiments are conducted to research the leaching mechanism of pollutants from coal waste rock in Jiaozuo mine field and their adsorption-desorption behaviors in soil, and coal waste rock and soil are sampled from several coal mines in Jiaozuo. The concentrations of SO4^2-, Cl^-, Ca, Mg, Cr, Pb, Zn, Mn, Cu, Cd, pH and electrical conductivity in leachate are measured. The experiments show that the pH of leachate is mildly alkali. The concentrations of SO4^2-,Ca, Mg, Zn and Mn exceed the criterions described in environmental quality standard GB5749-85. In earlier stage, the concentrations of pollutants in leachate from weathered coal waste rock are greater than those from un-weathered coal waste rock, and soil exhibits a high adsorption potential to pollutants from leachate, with 50% of pollutants from leachate adsorbed. The concentrations of pollutants in leachate attenuate rapidly in earlier stage, and then tend to be steady throughout the experiments. Since low-concentration leachate infiltrated through the soil which leads to pollutants desorbing from soil, the concentrations of the pollutants in the leachate are increased obviously. Heavy metal adsorption and desorption capacity of soil is related to pH, soil type, pollutant concentration in soil, adsorption capacity of soil, the pollutant concentration in leachate, etc.

关 键 词：煤矸石 淋滤 污染组分 土壤 吸附解吸 

分 类 号：X53[环境科学与工程—环境工程]