Pore-Scale Investigation of Micron-Size Polyacrylamide Elastic Microspheres (MPEMs) Transport and Retention in Saturated Porous Media

Yao, Chuanjin; Lei, Guanglun; Cathles, Lawrence M.; Steenhuis, Tammo S.

Pore-Scale Investigation of Micron-Size Polyacrylamide Elastic Microspheres (MPEMs) Transport and Retention in Saturated Porous Media

Type

Article

Authors

Yao, Chuanjin

Lei, Guanglun

Cathles, Lawrence M.
Steenhuis, Tammo S.

Online Publication Date

2014-04-24

Print Publication Date

2014-05-06

Date

2014-04-24

Abstract

Knowledge of micrometer-size polyacrylamide elastic microsphere (MPEM) transport and retention mechanisms in porous media is essential for the application of MPEMs as a smart sweep improvement and profile modification agent in improving oil recovery. A transparent micromodel packed with translucent quartz sand was constructed and used to investigate the pore-scale transport, surface deposition-release, and plugging deposition-remigration mechanisms of MPEMs in porous media. The results indicate that the combination of colloidal and hydrodynamic forces controls the deposition and release of MPEMs on pore-surfaces; the reduction of fluid salinity and the increase of Darcy velocity are beneficial to the MPEM release from pore-surfaces; the hydrodynamic forces also influence the remigration of MPEMs in pore-throats. MPEMs can plug pore-throats through the mechanisms of capture-plugging, superposition-plugging, and bridge-plugging, which produces resistance to water flow; the interception with MPEM particulate filters occurring in the interior of porous media can enhance the plugging effect of MPEMs; while the interception with MPEM particulate filters occurring at the surface of low-permeability layer can prevent the low-permeability layer from being damaged by MPEMs. MPEMs can remigrate in pore-throats depending on their elasticity through four steps of capture-plugging, elastic deformation, steady migration, and deformation recovery. © 2014 American Chemical Society.

Citation

Yao C, Lei G, Cathles LM, Steenhuis TS (2014) Pore-Scale Investigation of Micron-Size Polyacrylamide Elastic Microspheres (MPEMs) Transport and Retention in Saturated Porous Media. Environ Sci Technol 48: 5329–5335. Available: http://dx.doi.org/10.1021/es500077s.

Acknowledgements

We thank Douglas Caveney for help with constructing the transparent micromodel. This research was supported by Program for Changjiang Scholars and Innovative Research Team in University (IRT1294), the China Scholarship Council for Chuanjin Yao (Grant No. 201306450015), and the Fundamental Research Funds for the Central Universities of China (Project No. 11CX06025A).