针对尾矿库的重金属污染对生态环境及人类生活造成严重危害的状况,以辽宁省境内6个不同矿区的尾矿库作为研究对象,采用灰靶决策的方法,对其污染性进行量化研究及评价。系统分析不同重金属元素对环境的污染性,选取Zn、Pb、Cd、As、Cu、Cr、Hg共7种重金属元素,建立尾矿库重金属污染性评价指标体系。运用层次分析法和熵权法确定评价指标的主、客观权重,通过组合权重模型得到各评价指标对尾矿库污染性影响的最终组合权重值。基于灰色系统理论,建立多指标尾矿库重金属污染性灰靶决策模型,以污染临界值作为最优效果向量,即灰靶决策模型的靶心。计算6个待评价区块的效果向量与最优效果向量间的靶心距,根据靶心距的大小进行污染性排序,靶心距越大,矿区污染程度越严重。评价结果与实际情况较吻合,说明基于组合权重的多指标尾矿库重金属污染性灰靶决策模型对尾矿库的污染性进行评价是可行的。
In view of the situation of the heavy metal pollution of railings reservoir seriously harm the ecological environ- ment and human life, taking 6 different tailings reservoirs in Liaoning Province as research objects, the method of grey target decision is used to make the quantitative research and evaluation on their pollution. Pollution of different heavy metals to the environment is systematically analyzed and 7 heavy metals including Zn, Pb, Cd, As, Cu, Cr, Hg were selected as indexes to set up the heavy metal pollution of railings reservoir evaluation system. The analytic hierarchy process(AHP) and entropy weight method are adopted to determine the subjective and objective weight ,the final combinational weight of evaluation index impac- ting on the railings reservoir pollution is obtained by the combined weighting model. Based on the grey system theory, multi-in- dex heavy metal pollution of tailings reservoir grey target decision model is built. The pollution critical concentration is deter- mined as the optimal effect vector, that is, the target of the grey target decision-making model. The off-target distances of six undetermined blocks between effect vector and the optimal effect vector are calculated out. According to the value of off-target distances, the pollution of six tailings reservoirs can be ranked. The bigger the off-target distance is,the more serious the mine pollution is. The evaluation result is in good agreement with the actual situation, which indicate that the grey target decision model of multi-index heavy metal pollution of railings reservoir based on combinational weight for evaluating pollution of tailings reservoir is feasible.