空气-水界面崩和限速固体吸附控制 perfluoroalkyl 酸从 vadose 区域出
John F Stults1, Charles E Schaefer2, Yida Fang3
1CDM Smith, 14432 SE Eastgate Way, Suite 100, Bellevue, WA 98007, United States.
Journal of contaminant hydrology
|June 11, 2024
概括
从被灭火泡影响的土壤中漏的和多基物质 (PFAS) 偏离了平衡预测. 一个结合空气-水界面崩和缓慢的土壤脱落的新模型准确地预测了PFAS运动,这对于了解地下水污染至关重要.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 土壤科学 土壤科学
背景情况:
- 透和多醇基物质 (PFAS) 通过吸附到土壤和空气-水界面,在土壤中表现出强烈的保留.
- 在现场条件下,PFAS从受水性薄膜形成泡 (AFFF) 影响的土壤中浸出和脱落,往往偏离平衡预测.
研究的目的:
- 在模拟的降雨条件下,研究 perfluoroalkyl 酸 (PFAA) 从受 AFFF 影响的土壤中漏的行为.
- 开发和验证一个模型,准确预测PFAS漏,考虑到非平衡过程.
主要方法:
- 使用现场采集的AFFF冲击土壤进行实验室柱状研究.
- 对HYDRUS 1D模型的未和液压性能进行校准.
- 应用HYDRUS 1-D双站点漏模型,包括固体相速率限制和空气-水界面分区.
主要成果:
- 基于平衡的HYDRUS模拟和质量平衡计算与PFAS净质量流量一致,但无法预测孔水度.
- 一个包含空气-水界面崩和速度有限的脱吸的新的两站式模型显示,它可以更好地预测PFAA漏行为.
- 灵敏度分析证实了初始条件和速率有限的脱吸期的重要性.
结论:
- 均衡分区数据可以估计总PFAS大规模漏,但无法捕获速度有限的非Fickian运输.
- 开发的模型可以更好地了解不和土壤中的PFAS漏机制,这对于预测地下水污染至关重要.
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