Abstract:
This paper provides a comprehensive overview of research works on in-situ thermal conductive heating (TCH), including heat transfer in soil, desorption behavior of pollutants, and mass transfer mechanism within the site. Each stage influences the effectiveness of subsequent stages. Comparison of simulation and experimental results demonstrates that heat transfer and temperature rise in soil are related to the hydrogeological conditions, wells layout and pollutants contents. Thermal desorption of pollutants from soil particles can be influenced by four aspects: energy input, pollutant properties, soil characteristics, and the binding state of pollutant in soil. The exponential decay kinetic model exhibits better applicability for fitting thermal desorption processes. After desorption, the pollutants migrate in soil driven by high temperature and extraction pressure, while hydrogeological conditions of the site determine the actual migration path and rate. Applying convection-dispersion model allows for quantitatively describing the complex migration behavior of pollutants in heterogeneous sites. Future research should focus more on the composite effects of multiple factors in TCH and develop multi-field coupling models through the combination of numerical simulation and in-situ experiments. Accurate characterization and prediction of entire TCH process can improve remediation efficiency, reduce energy costs, and achieve sustainable low-carbon remediation.
摘要:
本文对原位导热加热(TCH)的研究工作进行了全面的概述,包括土壤中的热传递,污染物的解吸行为,和现场内的传质机制。每个阶段都会影响后续阶段的有效性。模拟和实验结果的比较表明,土壤的传热和温升与水文地质条件有关,井布置和污染物含量。土壤颗粒中污染物的热解吸可以受到四个方面的影响:能量输入,污染物属性,土壤特性,以及污染物在土壤中的结合状态。指数衰减动力学模型对于拟合热解吸过程具有更好的适用性。解吸后,污染物在高温和提取压力的驱动下在土壤中迁移,而场地的水文地质条件决定了实际的迁移路径和速率。应用对流扩散模型可以定量描述污染物在异质站点中的复杂迁移行为。未来的研究应更多地关注TCH中多种因素的复合效应,并通过数值模拟和原位实验相结合的方法建立多场耦合模型。整个TCH过程的准确表征和预测可以提高修复效率,降低能源成本,实现可持续的低碳修复。