US 12,140,028 B2
Cooling for geothermal well drilling
Matthew Toews, Calgary (CA); Michael Holmes, Calgary (CA); Ariel Torre, Calgary (CA); Aleksandr Vetsak, Calgary (CA); and Mark Hodder, Calgary (CA)
Assigned to Eavor Technologies Inc.
Filed by Eavor Technologies Inc., Calgary (CA)
Filed on Feb. 27, 2023, as Appl. No. 18/114,798.
Application 18/114,798 is a continuation of application No. PCT/IB2021/057883, filed on Aug. 27, 2021.
Claims priority of provisional application 63/184,706, filed on May 5, 2021.
Claims priority of provisional application 63/152,707, filed on Feb. 23, 2021.
Claims priority of provisional application 63/115,096, filed on Nov. 18, 2020.
Claims priority of provisional application 63/087,438, filed on Oct. 5, 2020.
Claims priority of provisional application 63/071,510, filed on Aug. 28, 2020.
Prior Publication US 2023/0228155 A1, Jul. 20, 2023
Int. Cl. E21B 7/18 (2006.01); E21B 3/02 (2006.01); E21B 7/04 (2006.01); E21B 7/14 (2006.01); E21B 17/00 (2006.01); E21B 36/00 (2006.01); E21B 43/26 (2006.01)
CPC E21B 7/18 (2013.01) [E21B 3/02 (2013.01); E21B 7/046 (2013.01); E21B 7/14 (2013.01); E21B 17/006 (2013.01); E21B 36/001 (2013.01); E21B 43/261 (2013.01)] 24 Claims
OG exemplary drawing
 
1. A method for forming a geothermal well system, the method comprising:
in a formation in a subterranean zone, forming a wellbore having an interface between the wellbore and the formation substantially impermeable to fluid, wherein the forming the wellbore comprises:
drilling, with a drill bit at a downhole end of a drill string, into the formation by breaking the rock at a rock face ahead of the drill bit, wherein an inherent temperature of the rock adjacent the rock face ahead of the drill bit is at least 250 degrees Celsius;
simultaneously with breaking the rock at the rock face with the drill bit, inducing, in the rock face, thermal stress greater than the tensile strength of the rock by flowing a water- or oil-based drilling fluid at having a temperature at the rock face that is sufficiently low so as to cause the thermal stress, the temperature of the drilling fluid at the rock face being less than the inherent temperature of the rock adjacent the rock face ahead of the drill bit and a difference between the inherent temperature of the rock adjacent the rock face ahead of the drill bit and the temperature of the drilling fluid at the rock face ahead of the drill bit being at least 100 degrees Celsius; and
sealing the wellbore without the use of casing to form the interface; and
circulating a geothermal working fluid in a closed loop through the wellbore.