Scholarlink

<p>The migration of heavy metals and the clogging problem of the drainage layer in landfill leachate are crucial factors influencing its long-term stability. This study focused on the evolution law of permeability, microstructural characteristics of the drainage layer, and heavy metal enrichment behavior. Using the landfill in Yanzhoutan Village as the engineering site, indoor model experiments were conducted to investigate the permeability performance, microstructural evolution, and heavy metal enrichment characteristics of multi-graded drainage media under prolonged leachate percolation. The results showed that the permeability coefficient of the drainage layer gradually declined as the percolation time increased, and this decline became more noticeable as the effective particle size reduced or the distance to the percolation inlet shortened. The variation of water-holding capacity demonstrated an opposite trend. Clogging of the drainage layer mainly occurred during the initial stage of percolation and then progressively stabilized. A larger effective particle size led to a lower pore-clogging rate. After the experiment, the average pore area declined as the number of pores rose, suggesting that larger pores were divided and subsequently filled. The order of heavy metal enrichment in the drainage layer was Mn &gt; Zn &gt; Pb &gt; &gt; Cr, with Zn and Pb showing significantly higher enrichment capacities than Cr. The fine-particle drainage layer showed a moderate level of Mn pollution. By influencing the initial permeability, formation of clogging materials, and changes in pore structure, particle size indirectly controls heavy metal adsorption and precipitation processes, increasing the vulnerability of finer particles to pollution accumulation. This study clarifies the relationship between the particle size of the drainage layer medium and its permeability, microstructural evolution, and heavy metal enrichment characteristics, offering insightful information about preventing pollution and operating landfills safely.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Study on the Permeability Performance, Microstructural Evolution, and Heavy Metal Enrichment Characteristics of Multi-graded Drainage Layers

  • 期刊论文

  • 发表日期：

    2026年7月7日

查看全文
  • Zhen Cai,
  • Nian Cai

摘要

The migration of heavy metals and the clogging problem of the drainage layer in landfill leachate are crucial factors influencing its long-term stability. This study focused on the evolution law of permeability, microstructural characteristics of the drainage layer, and heavy metal enrichment behavior. Using the landfill in Yanzhoutan Village as the engineering site, indoor model experiments were conducted to investigate the permeability performance, microstructural evolution, and heavy metal enrichment characteristics of multi-graded drainage media under prolonged leachate percolation. The results showed that the permeability coefficient of the drainage layer gradually declined as the percolation time increased, and this decline became more noticeable as the effective particle size reduced or the distance to the percolation inlet shortened. The variation of water-holding capacity demonstrated an opposite trend. Clogging of the drainage layer mainly occurred during the initial stage of percolation and then progressively stabilized. A larger effective particle size led to a lower pore-clogging rate. After the experiment, the average pore area declined as the number of pores rose, suggesting that larger pores were divided and subsequently filled. The order of heavy metal enrichment in the drainage layer was Mn > Zn > Pb > > Cr, with Zn and Pb showing significantly higher enrichment capacities than Cr. The fine-particle drainage layer showed a moderate level of Mn pollution. By influencing the initial permeability, formation of clogging materials, and changes in pore structure, particle size indirectly controls heavy metal adsorption and precipitation processes, increasing the vulnerability of finer particles to pollution accumulation. This study clarifies the relationship between the particle size of the drainage layer medium and its permeability, microstructural evolution, and heavy metal enrichment characteristics, offering insightful information about preventing pollution and operating landfills safely.