Patent ID: 11945996
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Basic materials chemistry (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A method of water shutoff, comprising:
providing a treatment fluid comprising a polymer, crosslinker, and a nitrogen-generating compound comprising a nitrite-containing compound through a wellbore into a water zone in a subterranean formation;
providing an acid to the water zone;
generating nitrogen gas in the water zone by a reaction of the nitrogen-generating compound, wherein the reaction is activated by the acid;
generating foam from the nitrogen gas and the treatment fluid in the water zone to give foamed polymer in the water zone; and
sealing the water zone with the foamed polymer, wherein sealing the water zone comprises allowing the foamed polymer to harden to give solid foam polymer in the water zone that blocks water flow from the water zone into the wellbore, thereby providing for water shutoff of the water zone.