Abstract：
Landfill mining (LFM) has gained widespread recognition due to its benefits in terms of resource utilization of landfill waste and reuse of landfill sites. However, it is important to thoroughly assess the associated environmental risks. This study simulated the pressure release induced from LFM in small-scale batch anaerobic reactors subject to different initial pressures (0.2-0.6 MPa). The potential risk of hydrogen sulfide (H2S) pollution resulting from pressure release caused by LFM was investigated. The results demonstrated that the concentration of H2S significantly increased following the simulated pressure treatments. At the low (25 °C) and high (50 °C) temperatures tested, the peak H2S concentration reached 19366 and 24794 mg·m-3, respectively. Both of these concentrations were observed under highest initial pressure condition (0.6 MPa). However, the duration of H2S release was remarkably longer (>90 days) at the low temperature tested. Microbial diversity analysis results revealed that, at tested low temperature, the sulfate-reducing bacteria (SRB) communities of various pressure-bearing environments became phylogenetically similar following the pressure releases. In contrast, at the high temperature tested, specific SRB genera (Desulfitibacter and Candidatus Desulforudis) showed further enrichment. Moreover, the intensified sulfate reduction activity following pressure release was attributed to the enrichment of specific SRBs, including Desulfovibrio (ASV585 and ASV1417), Desulfofarcimen (ASV343), Candidatus Desulforudis (ASV24), and Desulfohalotomaculum (ASV506 and ASV2530). These results indicate that the pressure release associated with LFM significantly increases the amount of H2S released from landfills, and the SRB communities have different response mechanisms to pressure release at different temperature conditions. This study highlights the importance of considering the potential secondary environmental risks associated with LFM.
摘要：
填埋采矿（LFM）由于其在垃圾填埋场废物的资源化利用和垃圾填埋场的再利用方面的优势而获得了广泛的认可。然而,彻底评估相关的环境风险非常重要。这项研究模拟了LFM在不同初始压力（0.2-0.6MPa）的小型间歇式厌氧反应器中引起的压力释放。研究了由LFM引起的压力释放导致的硫化氢（H2S）污染的潜在风险。结果表明，在模拟压力处理后，H2S的浓度显着增加。在测试的低温（25°C）和高温（50°C）下，H2S峰值浓度分别达到19366和24794mg·m-3。在最高初始压力条件(0.6MPa)下观察到这两种浓度。然而,在测试的低温下，H2S释放的持续时间明显更长（>90天）。微生物多样性分析结果表明,在测试的低温下，各种承压环境的硫酸盐还原细菌（SRB）群落在释放压力后变得系统发育相似。相比之下,在高温下测试，特定的SRB属（脱硫杆菌和念珠菌）显示出进一步的富集。此外，压力释放后硫酸盐还原活性增强归因于特定SRB的富集，包括脱硫弧菌(ASV585和ASV1417)，Desulfofarcimen(ASV343),拟南芥(ASV24)，和脱硫盐（ASV506和ASV2530）。这些结果表明，与LFM相关的压力释放显着增加了从垃圾填埋场释放的H2S的量，SRB群落在不同温度条件下对压力释放有不同的响应机制。这项研究强调了考虑与LFM相关的潜在次级环境风险的重要性。
