长期以来,对水中污染物迁移行为的研究一直不足。粘土通常用作不可渗透层或屏障以阻止污染物的迁移。然而,在一定条件下,粘土层可以表现出对水的渗透性,从而使污染物渗入并可能污染相邻的含水层。因此,为了控制和修复地下水污染,仔细检查和研究轻非水相液体(LNAPL)在aquitard中的迁移特性非常重要。为了评估Aquitard中有机污染物造成的环境风险,建立并设计了一个实验模型,以监测抽水条件下Aquitard中的LNAPL浓度。研究了泵送速率与LNAPL浓度之间的相关性。使用自行开发的有机玻璃沙箱模型来模拟LNAPL在抽水条件下在Aquitard中的迁移特性。设计了四个实验方案,不同的泵送率,aquitard厚度,和地下水位变化。LNAPL浓度曲线是通过系统地跟踪和分析Aquitard内各个位置的LNAPL水平得出的。结果表明,较高的抽速对应于LNAPL的迁移增加,导致在开采过程中更多的LNAPL进入抽油机井。较厚的aquitard对LNAPL表现出更明显的抑制作用,导致LNAPL在aquitard中的渗透时间延长。Aquitard内部的水位下降对LNAPL的迁移产生了明显的影响,随着抽水过程中水位的下降,LNAPL浓度继续下降。这些研究结果可以为控制和修复aquitards中的污染物奠定科学基础。
Research on the migration behaviors of contaminants in the
aquitard has been deficient for an extended period. Clay is commonly employed as an impermeable layer or barrier to stop the migration of contaminants. However, under certain conditions, the clay layer may exhibit permeability to water, thereby allowing contaminants to infiltrate and potentially contaminate adjacent aquifers. Consequently, it holds immense importance to scrutinize and investigate the migration characteristics of light non-aqueous phase liquid (LNAPL) within the aquitard for the purposes of groundwater pollution control and remediation. To evaluate the environmental risk posed by organic contaminants in the
aquitard, an experimental model was formulated and devised to monitor the LNAPL concentration in the
aquitard under pumping conditions. The correlation between pumping rate and LNAPL concentration was investigated. A self-developed plexiglass sandbox model was used to simulate the migration characteristics of LNAPL in the aquitard under pumping conditions. Four experimental scenarios were designed, varying pumping rates, aquitard thicknesses, and groundwater level changes. The LNAPL concentration curve was derived by systematically tracking and analyzing LNAPL levels at various locations within the aquitard. The results indicated that higher pumping rates corresponded to increased migration of LNAPL, resulting in greater LNAPL ingress into the pumping well during extraction. A thicker
aquitard demonstrated a more pronounced inhibitory effect on LNAPL, leading to an extended penetration time of LNAPL within the
aquitard. The drawdown within the aquitard exerted a discernible influence on LNAPL migration, with the LNAPL concentration continuing to decrease in tandem with declining water levels during pumping. These research findings can establish a scientific foundation for the control and remediation of contaminants within aquitards.