Process for the recovery of petroleum from subterranean formations
AssigneeDeutsche Texaco Aktiengesellschaft
InventorsKarl-Heinz Grodde, Hartwig Volz
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Abstract
An improved polymer flood process for the recovery of petroleum from a subterranean formation wherein a slug of a fresh water aqueous solution of a salt-insensitive polymer is injected into the formation prior to the undertaking of the polymer flood using a fresh water solution containing a partially hydrolyzed polyacrylamide.
Claims4
In a process for the recovery of petroleum from underground formations by means of a polymer flood employing a salt-sensitive partially hydrolyzed polyacrylamide in soft water, the improvement comprising the injection of a slug of a solution of a salt-insensitive polymer in soft water, immediately prior to the undertaking of said polymer flood, said salt-insensitive polymer being selected from the group consisting of a polysaccharide, a polyacrylamide hydrolyzed from 0% to 15%, and a cellulose ether.
A process for the recovery of petroleum from underground formations by means of a polymer flood comprising the steps of injecting a slug of a soft water solution of a salt-insensitive polyacrylamide polymer hydrolyzed from 0% to 15% and thereafter injecting a salt-sensitive partially hydrolyzed polyacrylamide solution in amounts of 10% to 40% pore volume.
Dependencies are inferred from the claim text.