Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China.
Department of Environmental Science, Zhejiang University, Hangzhou, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, 310058, China.
Environ Pollut. 2024 Nov 1;360:124624. doi: 10.1016/j.envpol.2024.124624. Epub 2024 Jul 26.
Initial volatile concentration (C) is a crucial parameter for the migration and diffusion of volatile organic pollutants (VOCs) from the soil to the atmosphere. The acquisition of C is, however, time-consuming and labor-intensive. This study developed a prediction model for C based on theoretical analysis and experimental simulations. The model was established by correlating the molecular kinetic and sorption potential energy. The pore structure and pore size distribution of the soil were analyzed based on the fractal theory of porous media, followed by calculating the sorption potential energy corresponding to each pore size. It was observed that the pore size distribution of soil influenced BTEX (benzene, toluene, ethylbenzene, and xylene) volatilization by impacting sorption potential energy. The soil parameters, such as organic matter and soil moisture content, and the initial concentration and physical properties of BTEX were coupled to the prediction model to ensure its practicability. Red soil was finally used to verify the accuracy and applicability of the model. The experimental and predicted values' maximum relative and root-mean-square errors were determined to be 24.2% and 11.7%, respectively. The model provides a simple, rapid, and accurate assessment of soil vapor emission content due to BTEX contamination. This study offers an economical and practical method for quantifying the amount of volatile BTEX in contaminated sites, providing a reference for its monitoring, control, and subsequent remediation.
初始挥发浓度 (C) 是挥发性有机污染物 (VOCs) 从土壤向大气迁移和扩散的关键参数。然而，C 的获取既耗时又费力。本研究基于理论分析和实验模拟，开发了一种用于预测 C 的模型。该模型通过关联分子动力学和吸附势能来建立。基于多孔介质分形理论，分析了土壤的孔隙结构和孔径分布，并计算了与每个孔径相对应的吸附势能。研究发现，土壤的孔径分布通过影响吸附势能来影响 BTEX（苯、甲苯、乙苯和二甲苯）的挥发。将土壤参数（如有机质和土壤水分含量）以及 BTEX 的初始浓度和物理性质与预测模型相结合，以确保其实用性。最后，使用红壤验证了模型的准确性和适用性。实验值和预测值的最大相对误差和均方根误差分别确定为 24.2%和 11.7%。该模型为评估由于 BTEX 污染而导致的土壤蒸气排放含量提供了一种简单、快速和准确的方法。本研究为量化污染场地中挥发性 BTEX 的数量提供了一种经济实用的方法，为其监测、控制和后续修复提供了参考。
