Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of Environment and Resources, Jilin University, 2519 Jiefang Road, Changchun, 130021, People's Republic of China.
Environ Sci Pollut Res Int. 2020 Oct;27(29):36316-36329. doi: 10.1007/s11356-020-09131-2. Epub 2020 Jun 18.
In situ thermal remediation can rapidly remove volatile organic pollutants, regardless of permeability or heterogeneity in the subsurface, which has received more attention in recent years. This study aims at investigating the heat transfer during thermal conduction heating (TCH), a heating method of in situ thermal remediation. The experiments were performed in a 134.5-cm tall × 107.5-cm wide × 7.5-cm thick tank containing a heating resistance to heat the aquifer and 62 thermocouples to measure temperature. The temperature of the points was recorded in real time through a multi-channel temperature patrol instrument. Then, isotherms were drawn, which were quantitatively analyzed from the aspects of temperature distribution, heated zone area, heat transfer distance, and influencing radius. The influence of groundwater velocity, aquifer medium, and heating resistance power was investigated. The results show the following: (1) The quantitative analysis proved that the higher the groundwater velocity, the faster the heated zone reaches a stable state. (2) The heated zone area in a coarse/fine sand aquifer is larger than that in a medium sand aquifer, and the stable time of the heated zone is in the order of fine sand < coarse sand < medium sand. (3) The greater the heating resistance power is, the more rapidly the heated zone reaches a stable state. (4) It has been quantitatively concluded that the V-shaped distribution of the heated zone is more obvious at a high groundwater velocity or with a high-power heating resistance. These findings are significant for the practical application of Thermal conduction heating.
原位热修复可以快速去除挥发性有机污染物，无论地下的渗透性或非均质性如何，近年来受到了更多的关注。本研究旨在研究热传导加热（TCH）过程中的传热，TCH 是原位热修复的一种加热方法。实验在一个 134.5 厘米高×107.5 厘米宽×7.5 厘米厚的水箱中进行，水箱中包含一个加热电阻来加热含水层和 62 个热电偶来测量温度。通过多通道温度巡检仪实时记录各点温度，然后绘制等温线，并从温度分布、加热区面积、传热距离和影响半径等方面进行定量分析。考察了地下水速度、含水层介质和加热电阻功率的影响。结果表明：（1）定量分析证明，地下水速度越高，加热区达到稳定状态的速度越快。（2）在粗/细砂含水层中的加热区面积大于中砂含水层，加热区的稳定时间顺序为细砂<粗砂<中砂。（3）加热电阻功率越大，加热区达到稳定状态的速度越快。（4）定量得出，在高地下水速度或高功率加热电阻的情况下，加热区的 V 形分布更为明显。这些发现对热传导加热的实际应用具有重要意义。
