污染场地原位热修复技术与能效分析

本文围绕原位热修复技术所存在的有效性和能耗难以评估的问题,基于原位热修复技术机制、影响因素、能效等方面进行系统分析,揭示原位热修复技术热量传递和污染物驱动机制,探讨热导率和电导率等原位热修复能效的影响因素;基于电阻加热(ERH)修复技术原位中试研究,分析了ERH系统的加热性能和该场地加热0100 d的温度场时空分布,解析温度空间分布差异的原因。研究表明,ERH存在电阻发热和电极井热传导两种机制,加热效率受电极井距离和地层环境影响,热量散失是未来原位热修复技术能效评估应关注和研究的因素。

Application and energy efficiency analysis of in-situ thermal remediation technology for contaminated sites

To address the difficulties associated with the effectiveness and efficiency assessments of in-situ thermal remediation (ISTR) technology, this study analyzed and revealed the principals of heat transfer and pollutant removal, the key influencing factors such as thermal conductivity and electrical conductivity, and the energy efficiency of ISTR. Based on the pilot-scale implementation of in-situ electrical resistance heating (ERH) remediation technology at a contaminated site, heating performance of the ERH system and the spatio-temporal distribution of the temperature field were analyzed. Further, the causes of spatial variation of temperature were investigated. According to the analysis, the site was heated primarily via electrical resistance heating and thermal conduction by the electrode well. The heating efficiency was affected by the electrode well distance and site lithological characteristics. Heat loss to the surface and around is a key factor for future energy efficiency assessment of ISTR technology.