Comparison of Agent-Enhanced Flushing for the Recovery of Crude Oil from Saturated Porous Media via Pore-Scale and Interfacial Experiments
Abstract
Subsurface remediation of nonaqueous phase liquid (NAPL) has proven challenging even when implementing more aggressive enhanced-flushing techniques. Synchrotron X-ray microtomography (SXM) was used to perform pore-scale examination of NAPL fragmentation, changes in blob morphology, and recovery. Three different advective flushing methods were employed: (1) surface-active agent (surfactant) flushing, (2) alkaline flushing, and (3) sequential alkaline-surfactant flushing. This set of experiments was conducted to determine effects on processes of fragmentation and recovery as a function of media composition (geochemical/mineralogical) and pH alterations due to calcium carbonate fraction. Results showed that the sequential flushing technique (alkaline → surfactant) yielded the highest recovery, 32% after 5 pore volumes (PV) of flushing. The crude oil (NAPL) distribution varied due to differences in porous medium mixture composition and type of fluid (i.e. surfactant vs. alkaline) used for flushing. Study results enhances understanding of the physical and chemical parameters/ properties that control mobilization of crude oil in saturated porous media. This can help reduce time and cost during remediation of contaminated sites that contain crude oil or less dense NAPL derivatives consistent with fuel-type petroleum hydrocarbons.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.H33N2176G
- Keywords:
-
- 1847 Modeling;
- HYDROLOGY;
- 1859 Rocks: physical properties;
- HYDROLOGY;
- 5104 Fracture and flow;
- PHYSICAL PROPERTIES OF ROCKS;
- 5139 Transport properties;
- PHYSICAL PROPERTIES OF ROCKS