紫木凼金矿开采过程中的环境效应:2.污染趋势分析

ENVIRONMENTAL EFFECT DURING THE EXPLOITATION PROCESSES OF ZHIMUDANG GOLD DEPOSIT: Ⅱ. ANALYSIS OF POLLUTION TREND

主要对紫木凼金矿区CN- 、As、Hg、Pb、Zn五个污染项目进行了趋势分析和污染预测。氰化物虽然是剧毒污染物 ,但它具有很强的自净降解作用 ,对矿区的污染影响不大 ,只是对于废液池的清洗外排必须先治理后排放。建立了As、Hg、Pb、Zn在各个污染途径中的定量分配模式。该模式表明 ,开采过程中As、Hg、Pb的大部分 ( 64 %以上 )进入废液池外排 ,其余的进入矿渣。在此基础上 ,对这些元素从 1 989年到 2 0 0 0年的开采总量、进入废液、土壤、积水坑的分量进行了计算 ,并给出了在堆场下伏粘土中各元素的饱和吸附量和开始外排的时间。

The aim of this paper is to analyze and predict the pollution trend of five toxic species: CN\+-, As, Hg, Pb and Zn during the exploitation process of the Zhimudang gold deposit. Although it is extremely toxic pollutive material, cyanide does not exert pollution to the environment of the mine field because of its extremely good self\|purification and degradation. It is important that the washing and drainage of waste liquid pool should not be done until total elimination of cyanide. Qualitative partition model of As, Hg, Pb and Zn in different kinds of media has been established, demonstrating that during the exploitation processes most of the As, Hg and Pb (above 64%) found their way into waste liquid pool and were drained out, and the others into mine waste. Based on the above model, the total amounts of exploitation of these elements, the fraction of these elements entering waste liquid, soil and dredged crater from 1989 to 2000, and also the saturated adsorbed amounts of clays underlying the gold mine accumulation field as well as the initial time of these clays to drain the penetrating liquid out are calculated.\;