煤矸石–粉煤灰–牛粪协同改良对重金属浸出行为的影响

Effect of Synergistic Amendment of Coal Gangue, Fly Ash, and Cattle Manure on Heavy Metal Leaching Behavior

摘要: 为探究煤矸石、粉煤灰与牛粪协同改良的土壤化效果，本研究设置不同配比处理，分析其对基质中Al、Cd、Mn、Cu、Fe、Zn等重金属浸出行为的影响。结果表明，各处理对重金属浸出的影响呈元素特异性：CS4 (煤矸石:粉煤灰:有机质 = 5:4:1)对Al、Mn、Cu的抑制效果最佳，而CS9 (4:1:5)虽有机质含量高，却导致Al大量释放；Fe和Zn在各处理中表现稳定，与对照无显著差异；Cd在有机质较高处理中浸出受抑制。适量粉煤灰可有效固定多数重金属，但过量有机质可能通过络合作用活化部分元素。CS4是控制重金属复合污染风险的优选配比，研究结果为煤矸石堆场的生态修复提供了理论依据。

Abstract: To investigate the soil-forming effects of the synergistic amendment of coal gangue, fly ash, and cattle manure, this study established different mixing ratios and analyzed their impacts on the leaching behavior of heavy metals such as Al, Cd, Mn, Cu, Fe, and Zn from the substrate. The results showed that the effects of different treatments on heavy metal leaching were element-specific. CS4 (coal gangue:fly ash:organic matter = 5:4:1) exhibited the best inhibition effects on Al, Mn, and Cu. In contrast, although CS9 (4:1:5) had a high organic matter content, it led to substantial Al release. Fe and Zn showed stable performance across all treatments, with no significant differences compared to the control. Cd leaching was suppressed in treatments with higher organic matter content. An appropriate amount of fly ash effectively immobilized most heavy metals, while excessive organic matter potentially activated certain elements through complexation. CS4 is the optimal ratio for controlling the risk of combined heavy metal pollution. These findings provide a theoretical basis for the ecological restoration of coal gangue dumps.