Effects of thermal desorption temperature up to 500 °C on the thermophysical properties and fertility of soil in organic-contaminated sites

Organic-contaminated soil Thermal desorption High temperature Fertility Thermal conductivity
["Wu, Yu-Hao","Wu, Yue-Fei","Zhu, Zi-Qin","Wang, Qing","Fan, Li-Wu","Yu, Zi-Tao","Li, Xiao-Dong","Song, Xin"] 2024-12-01 期刊论文
High-temperature thermal desorption is effective for remediating organic-contaminated sites, but its damage to soil functions and high energy consumption raise concerns. In this work, the variation of fertility indicators of two soils with thermal treatment temperature was investigated experimentally. To overcome the difficulties in measuring soil thermophysical properties under sealing and high-temperature conditions, two apparatus matching with the Hot Disk device were established and by which massive data were measured. The results show that, as temperature rises up to 500 degrees C, the combustion and decomposition of organic components and soil minerals gradually enhance, leading to a decrease in most fertility indicators, but an increase in grain size and pH. Available phosphorus and exchangeable potassium decrease with temperature rise first, but increase over 400 degrees C. Soil thermal conductivity and specific heat are positively correlated with temperature and water content. Water diffusion will intensify over 40 similar to 60 degrees C, leading to an intense increase in soil thermal conductivity. The results are expected to provide data basis and theoretical guidance for the comprehensive consideration of remediation effects, land reuse, and energy consumption in practical applications of thermal desorption remediation.
来源平台:RESULTS IN ENGINEERING