US 12,442,282 B1
Methods and compositions for thermally shocking subsurface formations
Fahad Khan, Dhahran (SA); Mohamed Ahmed Nasr Aldeen Mahmoud, Dhahran (SA); Arshad Raza, Dhahran (SA); Murtadha J. AlTammar, Dhahran (SA); and Shirish Patil, Dhahran (SA)
Assigned to Saudi Arabian Oil Company, Dhahran (SA); and King Fahd University of Petroleum & Minerals, Dhahran (SA)
Filed by King Fahd University of Petroleum and Minerals, Dhahran (SA); and Saudi Arabian Oil Company, Dhahran (SA)
Filed on Jun. 10, 2024, as Appl. No. 18/738,472.
Int. Cl. E21B 43/267 (2006.01); C09K 8/66 (2006.01); C09K 8/70 (2006.01); E21B 33/12 (2006.01)
CPC E21B 43/267 (2013.01) [C09K 8/665 (2013.01); C09K 8/70 (2013.01); E21B 33/12 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A method of thermally shocking a subsurface formation, the method comprising:
introducing an aqueous solution, ammonium chloride, and sodium hydroxide into a wellbore fluidly connected to the subsurface formation;
forming an endothermic fluid composition, wherein the endothermic fluid composition comprises an aqueous solution, ammonium chloride, and sodium hydroxide, wherein:
a concentration of the ammonium chloride in the endothermic fluid composition is from 0.1 Molar to 5 Molar, and
a concentration of the sodium hydroxide in the endothermic fluid composition is from 0.1 Molar to 32 Molar;
reacting the ammonium chloride and sodium hydroxide, thereby decreasing a temperature of the endothermic fluid and producing ammonia; and
exposing the reacted endothermic fluid composition to the subsurface formation, thereby thermally shocking at least a portion of the subsurface formation and inducing one or more fractures in the same.