| 【文章摘要】 Acid mine drainage(AMD) with high concentrations of sulfates and metals is generated by the oxidation of sulfide bearing wastes. Ca CO_3-rich marble cutting waste is a residual material produced by the cutting and polishing of marble stone. In this study, the feasibility of using the marble cutting waste as an acid-neutralizing agent to inhibit AMD and immobilize heavy metals from copper flotation tailings(sulfide-bearing wastes) was investigated. Continuous-stirring shake-flask tests were conducted for 40 d, and the p H value, sulfate content, and dissolved metal content of the leachate were analyzed every 10 d to determine the effectiveness of the marble cutting waste as an acid neutralizer. For comparison, Ca CO_3 was also used as a neutralizing agent. The average p H value of the leachate was 2.1 at the beginning of the experiment(t = 0). In the experiment employing the marble cutting waste, the p H value of the leachate changed from 6.5 to 7.8, and the sulfate and iron concentrations decreased from 4558 to 838 mg/L and from 536 to 0.01 mg/L, respectively, after 40 d. The marble cutting waste also removed more than 80wt% of heavy metals(Cd, Cr, Cu, Ni, Pb, and Zn) from AMD generated by copper flotation tailings. |