Abstract: A method is provided for blocking high permeability regions in subterranean geological formations, using a reinforced swelling clay gel. A reinforced clay slurry is prepared by mixing swelling clay, such as bentonite, an aqueous solution containing the salt of certain cations, which inhibit clay swelling, and a reinforcing agent. The cations K+, Ca2+, Mg2+, Cs2+, Fe2+, Al3+ and NR4+, where each R can independently be H, CH3, C6H5, or CH2CH3, and combinations thereof, among others, are clay swelling inhibitors. The reinforcing agent is non-swelling particles, including, without limitation, particles of produced sand, silica sand, sandy or silty soil, crushed rock, minerals, mine tailings, and combinations thereof. The reinforced clay slurry is introduced into a geological formation, where it preferentially enters high permeability regions.
Type:
Grant
Filed:
June 12, 2000
Date of Patent:
April 13, 2004
Assignee:
Alberta Oil Sands & Research Authority
Inventors:
Zhihong Zhou, Bernard Tremblay, Brian Wayne Wiwchar