US 12,258,516 B2
Methods to use water shutoff material composition comprising alkaline nanosilica dispersion and sodium bicarbonate in downhole conditions
Rajendra Arunkumar Kalgaonkar, Dhahran (SA); and Vikrant Wagle, Dhahran (SA)
Assigned to Saudi Arabian Oil Company, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Dec. 15, 2021, as Appl. No. 17/551,946.
Prior Publication US 2023/0183545 A1, Jun. 15, 2023
Int. Cl. C09K 8/42 (2006.01); C09K 8/487 (2006.01)
CPC C09K 8/426 (2013.01) [C09K 8/487 (2013.01); C09K 2208/10 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method of reducing water production in a wellbore, the method comprising:
introducing an alkaline nanosilica dispersion with a first pH to the wellbore such that it contacts a water producing zone of the wellbore;
introducing a sodium bicarbonate activator to the wellbore such that it contacts the alkaline nanosilica dispersion in the water producing zone and decreases the first pH of the alkaline nanosilica dispersion, thereby forming a water shutoff material; and
forming a gelled solid from the water shutoff material in the water producing zone, thereby reducing water production in the wellbore;
wherein:
the sodium bicarbonate activator is present in an amount in a range of from 25 weight percent to 40 weight percent of the water shutoff material, and
the water shutoff material is formed within the wellbore.