US 11,788,390 B2
Self-powered downhole injection systems and methods for operating the same
Tao Chen, Dhahran (SA); and Qiwei Wang, Dhahran (SA)
Assigned to Saudi Arabian Oil Company, Dhahran (SA)
Filed by Saudi Arabian Oil Company, Dhahran (SA)
Filed on Feb. 12, 2021, as Appl. No. 17/174,445.
Prior Publication US 2022/0259954 A1, Aug. 18, 2022
Int. Cl. E21B 43/12 (2006.01); E21B 33/068 (2006.01); E21B 34/02 (2006.01); E21B 47/00 (2012.01)
CPC E21B 43/12 (2013.01) [E21B 33/068 (2013.01); E21B 34/02 (2013.01); E21B 47/00 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A method for pumping chemicals down a wellbore, the method comprising:
passing a well material comprising at least one of a fluid or gas from the wellbore at a well material pressure to a wellhead assembly in communication with the wellbore, wherein the well material is material extracted from a subterranean hole through the wellbore;
maintaining a wellhead pressure portion of the wellhead assembly at a wellhead pressure equal to the well material pressure by passing at least a portion of the well material to the wellhead pressure portion of a pumping chamber through a wellhead pressure inlet valve positioned between the wellhead assembly and the wellhead pressure portion, wherein the wellhead pressure inlet valve is operable between a closed position and an open position, so as to control the portion of the well material passed from the wellhead assembly to the wellhead pressure portion, thereby applying a force on a movable plate positioned within the pumping chamber, wherein the pumping chamber defines the wellhead pressure portion and a chemical portion separated by the movable plate;
applying a pressure on chemicals positioned in the chemical portion of the pumping chamber with the movable plate; and
moving the chemicals from the chemical portion of the pumping chamber to the wellbore.