Release and Transport Characteristics of Heavy Metal Pollutants in Tailings Pond

Abstract

The lead-zinc tailings pond contains a significant concentration of heavy metal pollutants, such as lead, zinc, copper, chromium, cadmium, mercury, and arsenic. These pollutants exist in the form of ions within the tailings. External environmental factors can facilitate the release and transportation of these heavy metal elements from the tailings, resulting in pollution. The factors influencing pollutant release and variations in heavy metal tailings transport across different media were investigated by employing statistical analysis, leaching tests, and heavy metal soil column experiments based on the results of a case study on the Qingshan lead-zinc mining area. The multi-component solute release transport model for tailings to examine the interplay between concentration and seepage fields was constructed by considering hydrodynamics, mass transfer, and chemical reactions. The COMSOL software was performed to develop a customized model for the transport of heavy metal pollutants, wherein specific boundary conditions were set to enable quantitative analysis and interpretation of the release and migration of heavy metal solutes in tailings. The present study establishes a foundation for comprehending the migration patterns, pollution pathways, and mechanisms of heavy metal pollutants in tailings ponds. Furthermore, it provides indispensable technical support for addressing heavy metal contamination in lead-zinc mining regions and developing impermeable systems for tailings ponds.