The selection of mine tunnel wastewater treatment process and its application effect

摘要

The wastewater of lead and zinc mine tunnels contain Pb. Cd, Zn and other harmful heavy metals, and the features of these substances are not alike in different tunnels' wastewater because of the impact of the pH value of groundwater, the ore mineral assemblages, the oxidation degree of ore body and the conditions of the mine. According to different characteristics of tunnel wastewater, specific wastewater treatment processes were established to reduce the project investment, save energy and the quantity of reagent. Perfect treatment effects are obtained, and the economic and environmental benefits are remarkable. The designed combination technologies used in 8 wastewater treatment plants are as follows: (i) combination of coagulation, sediment and filtration; (ii) combination of preformed precipitate and PE unpowered filter; (iii) combination of pH adjustment, preformed precipitate, coagulate and sediment. All the wastewater treatment plants have operated normally and meet the emission standards and have been accepted by the Environment Administration Department. The planned delightful emission reduction of heavy metals will be obtained in 169 kg for Cd, 2.94 t for Zn and 1.245 t for Pb every year.