Enhanced NAPL Removal and Mixing With Engineered Injection and Extraction

Aquifer remediation with in-situ soil washing techniques and enhanced oil removal typically involves the injection of liquid solutions into geological formation to displace mobilize non-aqueous phase liquids (NAPLs). The efficiency these systems is oftentimes low because displacing fluid bypasses large quantities NAPL due inherent complexity a heterogeneous natural system. Here, engineered extraction (EIE) generated by rotating periodic proposed as method enhance mixing. To evaluate method, we perform two-phase flow simulations in multiple realizations random permeability fields different correlation structures connectivity between wells embedded five-spot pattern. Results show that EIE can significantly improve mixing depending on several controlling factors. effects are more significant under unfavorable conditions, is, when well-connected through preferential channels, permeabilities highly heterogeneous, and/or mobility ratio wetting non-wetting fluids larger than one. Removal reaches its maximum value Kubo number close one, saturation front travels one range field an pulse. These develop just few cycles. However, should undergo first early stage detrimental order maximize long term. not only enhances but also reduces uncertainty, making system reliable less dependent heterogeneity.