Using phase diagrams to predict the performance of cosolvent floods for NAPL remediation
Cosolvent flooding using water miscible solvents such as alcohols has been proposed as an in situ NAPL remediation technique. This process is conceptually similar to enhanced oil recovery (EOR) using alcohols and some surfactant formulations. As a result of interest in the EOR aspects of these systems, analytical and graphical methods based on fractional flow theory were developed in the petroleum engineering literature for modeling these floods. The existing fractional flow solutions have not been used previously in environmental applications of cosolvent flooding, but they are applicable and provide many useful insights into the process. These applications are discussed, with an emphasis on explaining the mechanisms which tend to mobilize trapped NAPL during a cosolvent flood. The theory provides a simple way to predict the general behavior of a cosolvent flood using the phase diagram. It is concluded that the one-dimensional performance of a cosolvent flood can be predicted largely by inspection of the ternary phase diagram. In particular, the nature of the cosolvent flood depends primarily on the position of the cosolvent injection concentration relative to a critical tie line extension which passes through the plait point, tangent to the binodal curve.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 290228
- Journal Information:
- Ground Water Monitoring and Remediation, Journal Name: Ground Water Monitoring and Remediation Journal Issue: 3 Vol. 18; ISSN 1069-3629; ISSN GWMREV
- Country of Publication:
- United States
- Language:
- English
Similar Records
A field test of in-situ NAPL removal by cosolvent flooding
Numerical simulation of field scale cosolvent flooding for LNAPL remediation