Abstract：
Clarifying the occurrence and morphological characteristics of petroleum hydrocarbons (PHs) in soil can facilitate a comprehensive understanding of their migration and transformation patterns in soil/sediment. Additionally, by establishing the dynamic transformation process of each occurrence state, the ecological impact and environmental risk associated with PHs in soil/sediment can be assessed more precisely. The adsorption experiments and closed static incubation experiments was carried out to explore the PHs degradation and fraction distribution in aged contaminated soil under two remediation scenarios of natural attenuation (NA) and bioaugmentation (BA) by exogenous bacteria through a new sequential extraction method based on Tenax-TA, Hydroxypropyl-β-cyclodextrin and Rhamnolipid (HPCD/RL), accelerated solvent extractor (ASE) unit and alkaline hydrolysis extraction. The adsorption experiment results illustrated that bioaugmentation could promote the desorption of PHs in the adsorption phase, and the soil-water partition coefficient Kd decreased from 0.153 L/g to 0.092 L/g. The incubation experiment results showed that compared with natural attenuation, bioaugmentation could improve the utilization of PHs in aged soil and promote the generation of non-extractable hydrocarbons. On the 90th day of the experiment, the concentrations of weakly adsorbed hydrocarbons in the natural attenuation and bioaugmentation experimental groups decreased by 46.44% and 87.07%, respectively, while the concentrations of strongly adsorbed hydrocarbons and non-extractable hydrocarbons increased by 77.93%, 182.14%, and 80.91%, and 501.19%, respectively, compared their initial values. We developed a novel dynamic model and inverted the kinetic parameters of the model by the parameter scanning function and the Markov Chain Monte Carlo (MCMC) method based on the Bayesian approach in COMSOL Multiphysics® finite element software combined with experimental data. There was a good linear relationship between experimental interpolation data and model prediction data. The R2 for the concentrations of weakly adsorbed hydrocarbons ranged from 0.9953 to 0.9974, for strongly adsorbed hydrocarbons from 0.9063 to 0.9756, and for non-extractable hydrocarbons from 0.9931 to 0.9982. These extremely high correlation coefficients demonstrate the high accuracy of the parameters calculated using the Bayesian inversion method.
摘要：
明确石油烃在土壤中的赋存状态和形态特征,有助于全面了解石油烃在土壤/沉积物中的迁移和转化规律。此外,通过建立每个发生状态的动态转换过程，可以更准确地评估与土壤/沉积物中PHs相关的生态影响和环境风险。通过基于Tenax-TA的新型顺序提取方法，进行了吸附实验和封闭静态孵育实验，以探索外源细菌自然衰减（NA）和生物强化（BA）两种修复方案下老化污染土壤中PHs的降解和分数分布。羟丙基-β-环糊精和鼠李糖脂（HPCD/RL），加速溶剂萃取器(ASE)装置和碱水解萃取。吸附实验结果表明，生物强化可以促进PHs在吸附阶段的解吸，土水分配系数Kd由0.153L/g降至0.092L/g。孵化实验结果表明,与自然衰减相比,生物强化可以提高老化土壤中PHs的利用率，促进不可提取烃的产生。在实验的第90天,自然衰减和生物强化实验组的弱吸附烃浓度分别下降了46.44%和87.07%,分别,强吸附烃和不可萃取烃的浓度增加了77.93%，182.14%，80.91%，和501.19%，分别,比较它们的初始值。我们开发了一个新的动力学模型，并通过参数扫描函数和基于COMSOLMultiphysics®有限元软件中的贝叶斯方法结合实验数据的马尔可夫链蒙特卡罗（MCMC）方法反演了模型的动力学参数。实验插值数据与模型预测数据之间存在良好的线性关系。弱吸附烃浓度的R2为0.9953至0.9974，强吸附烃的R2为0.9063至0.9756，不可萃取烃的R2为0.9931至0.9982。这些极高的相关系数证明了使用贝叶斯反演方法计算的参数的高精度。
