Release Characteristics of Pb from Zn-Pb Mine Tailings Under Simulation Leaching Conditions

Abstract In this paper, the results obtained from various leaching tests to determine the leaching behavior of lead from lead-zinc mine tailing under natural conditions were evaluated. In order to measure the level of toxicity of the tailings, synthetic precipitation leaching procedure (SPLP), toxicity characteristic leaching procedure (TCLP), leachate extraction procedure (LEP), and field leach test (FLT) protocols were used. The effect of liquid to solid ratio, particle size, contact time, and pH on lead release from tailings was also tested. Based on the results, the release of lead from the tailings was entirely affected by pH and amphoteric leaching behavior was observed. According to the results of the TCLP leaching protocol, the tailings categorized as hazardous material. Lead mobility index for S1 and S2 samples were 51% and 5.6%, respectively. The release of lead from the tailings was affected by the solubility process. The highest amount of lead release from S1 and S2 samples were observed in the particle size range of 0.3-0.5 mm and 0.6-1.0, mm respectively. According to the results, management of tailings and prevention of the release of lead into the environment, requires a special strategy. Controlling the amount of pore water, the size range of tailing particles in order to prevent wind erosion, prevent in situ pH changes, and acidification of tailings, and classification is essential factors in tailing management. In fact, health and diet security, climate change, safe water, accountable production, biodiversity, and ultimately the people must be considered in the planning of the authorities.