"Large volumes of fracturing fluid are required in shale slickwater fracs, and a considerable amount of polymer friction reducer would remain in microfractures if the polymer has not been broken before gas production. It is of major interest to evaluate the effect of polymer on water/gas flow behavior in the microfractures of shale reservoirs. We fabricated six shale fracture models with different fracture widths and set up a core flooding apparatus to conduct brine/gas-injection experiments before and after polymer treatment. A method by which to calculate the residual resistance factor for gas (Frr,gas) was defined. The experimental results illustrate that polymer can reduce the permeability to water more than to gas. In the first cycle of brine/gas injection experiments after polymer treatment, the residual resistance factor for brine (Frr,water) and Frr,gas exhibited power-law characteristics through their shear rate and superficial gas velocity, respectively. The Frr,water and Frr,gas tended to decrease as the fracture width grew. Surprisingly, the Frr,gas was less than one in larger fractures in which Frr,gas tended to stabilize after polymer treatment, which indicates that polymer treatment does not impair gas flow in wider fractures, and may even improve it. The mechanisms responsible for disproportionate permeability reduction (DPR) in the fractured shales were proposed in this paper."--Abstract, page iii.
Geosciences and Geological and Petroleum Engineering
M.S. in Petroleum Engineering
Missouri University of Science and Technology
xii, 76 pages
© 2015 Lingbo Liu, All rights reserved.
Thesis - Open Access
Library of Congress Subject Headings
Permeability -- Testing
Oil fields -- Production methods
Oil saturation in reservoirs
Polymers -- Analysis
Electronic OCLC #
Link to Catalog Recordhttp://laurel.lso.missouri.edu/record=b10848587~S5
Liu, Lingbo, "Effect of polymer on disproportionate permeability reduction to gas and water for fractured shales" (2015). Masters Theses. 7405.