Effects of cover made of fly ash for controlling the harm from coal waste

摘要

The high sulfur coal waste that releases toxic gas, highly acidic, sulfate, and metals-rich drainage is a serious environmental problem, contaminating air, soil and water in coal mining areas in China. The most serious safety issues associated with surface disposal of high sulfur coal waste due to spontaneous combustion as a result of the oxidation of sulfide which likely leads to geo-disasters and environmental pollution. In order to study the effect of using fly ash for controlling harm from coal waste, two column tests were conducted to determine if the fly ash covered could be used for the control of harm from coal waste. We investigated the effect of the fly ash covered on controlling harm from coal waste. The results come from experiment data analyses show that the fly ash covered can effectively increase pH value and decrease Eh, EC, SO42-and iron ion concentrations of the contaminants from coal wastes. The fly ash cover can effectively control harm from coal waste heap by preventing the oxidation of sulfide in situ treatment systems.