Subsea drilling systems and methods
AssigneeSchlumberger Technology Corporation
InventorsRod William Shampine, David Milton Eslinger
Life of this patent
Estimating the term…
Abstract
Apparatus and methods for performing subsea drilling operations. An example method may include receiving drilling fluid from a drilling fluid source at a first pressure by a pressure exchanger located within a subsea environment and receiving seawater from the subsea environment at a second pressure by the pressure exchanger to increase pressure of the drilling fluid within the pressure exchanger to a third pressure. The second and third pressures are substantially greater than the first pressure. The method may further include discharging the drilling fluid from the pressure exchanger into piping to communicate the drilling fluid to a drill forming a wellbore in a seabed and discharging the seawater from the pressure exchanger into the subsea environment.
Claims20
An apparatus comprising:
- a drilling system located on a seabed and operable to drill a wellbore through a rock formation below the seabed, wherein the drilling system comprises:
- a drill operable to drill the wellbore;
- piping operable to convey the drill and communicate drilling fluid to the drill during drilling operations;
- a pump operable to pump seawater;
- and
- a pressure exchanger fluidly connected with the pump and the piping, wherein the pressure exchanger is operable to:
- receive the drilling fluid at a first pressure;
- receive the seawater from the pump at a second pressure to pressurize the drilling fluid to a third pressure, wherein the second and third pressures are substantially greater than the first pressure;
- discharge the drilling fluid into the piping;
- and
- discharge the seawater into a subsea environment;
- and
- wherein the pressure exchanger comprises:
- a housing having a bore extending between first and second ends of the housing;
- a rotor rotatably disposed within the bore and comprising at least one chamber extending through the rotor between the first and second ends of the housing;
- a first cap covering the bore at the first end of the housing, wherein the first cap comprises a drilling fluid inlet and a drilling fluid outlet;
- and
- a second cap covering the bore at the second end of the housing, wherein the second cap comprises a seawater inlet and a seawater outlet.
A method comprising:
- receiving, into a chamber extending through a rotor rotatably disposed within a pressure exchanger that is located within a subsea environment, drilling fluid from a drilling fluid source at a first pressure;
- receiving, into the chamber, seawater from the subsea environment at a second pressure to increase pressure of the drilling fluid within the chamber to a third pressure, wherein the second and third pressures are substantially greater than the first pressure;
- discharging the drilling fluid from the chamber and into piping to communicate the drilling fluid to a drill connected with the piping forming a wellbore in a seabed;
- and
- discharging the seawater from the chamber and into the subsea environment.
A method comprising:
- pumping drilling fluid from a wellbore at a first pressure into a pressure exchanger located within a subsea environment, wherein the pressure exchanger comprises a rotor having at least one chamber extending through the rotor, and wherein pumping drilling fluid into the pressure exchanger comprises pumping the drilling fluid into the at least one chamber via a drilling fluid inlet of the pressure exchanger;
- pumping seawater from the subsea environment at a second pressure into the pressure exchanger to discharge the drilling fluid out of the pressure exchanger at a third pressure, wherein pumping seawater into the pressure exchanger comprises pumping the seawater into the at least one chamber via a seawater inlet of the pressure exchanger to increase the pressure of the drilling fluid within the at least one chamber, wherein discharging the drilling fluid out of pressure exchanger comprises discharging the drilling fluid from the at least one chamber via a drilling fluid outlet of the pressure exchanger, and wherein the second and third pressures are substantially greater than the first pressure;
- discharging the seawater out of the pressure exchanger into the subsea environment, wherein discharging the seawater out of the pressure exchanger comprises discharging the seawater from the at least one chamber via a seawater outlet of the pressure exchanger;
- communicating the drilling fluid discharged from the pressure exchanger through piping to a drill connected with the piping;
- and
- rotating the drill to form the wellbore in a seabed.
Dependencies are inferred from the claim text.