Investigation on Transport Behavior of Nanogel in Low Permeable Porous Medium
Nano-sized crosslinked polymeric particles (nanogels) have the advantages of both nanoparticles and hydrogels for enhanced oil recovery in the oil and gas industries. Although some encouraging progress in the application has been made, the transport behavior of nanogels through porous media are still not clear. In this work, a series of filtration experiments using membrane filter were performed to study the effect of nanogel diameter, pore size, and differential pressure on the transport behavior. The equilibrium filtration rate, which is a key parameter to indicate the transport behavior during steady state, increased from 0.19 to 5.71 mL/min when the pore size changed from 0.05 to 0.8 µm, and increased from 1.02 to 1.99 mL/min when the differential pressure raised from 10 to 30 psi. Experimental results demonstrated nanogels present smaller diameter (105.7 nm) and lower absolute value of zeta-potential (−18.9 mV) in 10 wt% NaCl solution than distilled water (295.3 nm and −82.5 mV). The higher salt concentration resulted in a better nanogel injectivity (equilibrium filtration rate increased from 0.77 to 4.52 when NaCl concentration changed from 0 to 10 wt%), which indicated the diameter of nanogel is a more determining factor than the nanogel strength. When the pore size was smaller than ~3 times of the naongel diameter, the equilibrium filtration rate became independent to the differential pressure and nanogels started to form face plugging on the membrane. The core filtration tests demonstrated that the nanogels maintained similar transport behavior through the limestone cores and membrane filters that the resistance factor is 26.59 in membrane and 18.56 in core with similar pore diameter. The transport behaviors of nanogel and corresponding mechanisms are summarized by the matching relationship between the diameter of nanogel and the pore size in low permeable porous medium.
P. Han et al., "Investigation on Transport Behavior of Nanogel in Low Permeable Porous Medium," Journal of Petroleum Science and Engineering, vol. 178, pp. 999 - 1005, Elsevier B.V., Jul 2019.
The definitive version is available at https://doi.org/10.1016/j.petrol.2019.04.020
Geosciences and Geological and Petroleum Engineering
Center for Research in Energy and Environment (CREE)
Keywords and Phrases
Filtration; Membrane; Nanogel; Transport
International Standard Serial Number (ISSN)
Article - Journal
© 2019 Elsevier B.V., All rights reserved.
01 Jul 2019
The authors gratefully acknowledge the financial support from the United States Department of Energy (DOE) under Contract DE-FE0024558 and the China Scholarship Council under the Grant CSC NÂ° 201608040012.