Electric submersible pump (ESP) shroud system

Patent metadata

Field	Value
Publication number	US-12221868-B2
Application number	US-202418610817-A
Country	US
Kind code	B2
Filing date	Mar 20, 2024
Priority date	Sep 28, 2022
Publication date	Feb 11, 2025
Grant date	Feb 11, 2025

Abstract

An electric submersible pump (ESP) assembly. The ESP assembly comprises an electric motor; a seal section coupled to the electric motor; a fluid intake coupled to an uphole end of the seal section, wherein the fluid intake defines a plurality of inlet ports; a gas separator comprising a plurality of gas phase discharge ports, and at least one liquid phase discharge port, wherein the gas separator is located uphole of the fluid intake; a centrifugal pump comprising a fluid inlet at a downhole end, wherein the at least one liquid phase discharge port of the gas separator is fluidically coupled to the fluid inlet of the centrifugal pump; and an inverted shroud assembly, wherein a downhole end of the inverted shroud assembly is coupled to an outside of the gas separator downhole of the gas phase discharge ports of the gas separator and uphole of the fluid intake.

First claim

What is claimed is:

1. A method of lifting a fluid in a wellbore, comprising:
running an electric submersible pump (ESP) assembly into the wellbore, wherein the ESP assembly comprises
an electric motor,
a gas separator configured to receive rotating power from the electric motor, having at least one gas phase discharge port, and having at least one liquid phase discharge port,
a pump located uphole of the gas separator and having a fluid inlet that is fluidically coupled to the at least one liquid phase discharge port of the gas separator, and
an inverted shroud coupled to an outside of the gas separator downhole of the gas phase discharge ports of the gas separator;

providing electric power to the electric motor;
flowing the fluid into the gas separator;
separating a first portion of the fluid from a second portion of the fluid by the gas separator;
exhausting the first portion of the fluid by the gas separator out the plurality of gas phase discharge ports of the gas separator;
flowing the second portion of the fluid by the gas separator via the at least one liquid phase discharge port to the fluid inlet of the pump;
lifting the second portion of the fluid by the pump uphole in a production tubing coupled to an outlet of the pump;
flowing the first portion of the fluid uphole inside the inverted shroud assembly;
flowing the first portion of the fluid downhole in an annulus defined by an inside of the wellbore and an outside of the inverted shroud assembly;
bubbling gas out of the first portion of the fluid as it flows downhole in the annulus defined by an inside of the wellbore and the outside of the inverted shroud assembly to produce a third portion of the fluid, wherein the third portion of the fluid has a lower gas-to-liquid ratio than the gas-to-liquid ratio of the first portion of the fluid; and
recirculating the third portion of the fluid into the fluid intake.

2. The method of claim 1 , further comprising:
receiving a gas slug;
mixing the third portion of the fluid with the gas slug at the gas separator.

3. The method of claim 1 , wherein the ESP assembly comprises a fluid intake disposed downhole of the gas separator that receives the fluid from the wellbore and flows the fluid into the gas separator, wherein the inverted shroud comprises a sealing ring that couples the inverted shroud to an outside of the gas separator downhole of the gas phase discharge ports, wherein the inverted shroud extends downhole past the gas phase discharge ports of the gas separator and couples to an outside of the fluid intake downhole of a plurality of inlet ports defined by the fluid intake, wherein the inverted shroud defines a first chamber downhole of the sealing ring and defines a second chamber uphole of the sealing ring.

4. The method of claim 3 , wherein receiving fluid by the fluid intake comprises receiving fluid into the first chamber, wherein recirculating the third portion of the fluid into the fluid intake comprises receiving the third portion of the fluid into the first chamber, and where flowing the first portion of the fluid uphole inside the inverted shroud assembly comprises flowing the first portion of the fluid uphole inside the second chamber.

5. The method of claim 4 , wherein the inverted shroud assembly defines inlet ports downhole of the sealing ring that receives the fluid and the third portion of the fluid into the first chamber.

6. The method of claim 1 , wherein the uphole end of the inverted shroud assembly is coupled to an outside of the pump or an outside of the production tubing by an outlet clamp, and wherein flowing the first portion of the fluid uphole inside the inverted shroud comprises flowing the first portion of the fluid out of outlet ports defined by the outlet clamp.

7. The method of claim 1 , wherein ESP assembly further comprises a seal section located uphole of the electric motor and wherein the outside diameter of the inverted shroud is about the same as the outside diameter of the seal section.

8. The method of claim 1 , wherein the electric motor comprises a first drive shaft; wherein the ESP assembly comprises a seal section located uphole of the electric motor having a second drive shaft coupled to the first drive shaft; wherein the ESP assembly comprises a fluid intake located uphole of the seal section and located downhole of the gas separator.

9. The method of claim 1 , wherein the fluid comprises hydrocarbons.

10. The method of claim 1 , wherein the fluid comprises hot water and the wellbore is a geothermal well.

11. A method of lifting fluid in a wellbore, comprising:
running an electric submersible pump (ESP) assembly into the wellbore, wherein the ESP assembly comprises
an electric motor having a first drive shaft;
a seal section having a second drive shaft, wherein the seal section is located uphole of the electric motor and a downhole end of the second drive shaft is coupled to an uphole end of the first drive shaft;
a fluid intake located uphole of the seal section, wherein the fluid intake defines a plurality of inlet ports;
a gas separator comprising a third drive shaft, at least one gas phase discharge port, and at least one liquid phase discharge port, wherein the gas separator is located uphole of the fluid intake and a downhole end of the third drive shaft is coupled to an uphole end of the second drive shaft;
a pump located uphole of the gas separator, the at least one liquid phase discharge port of the gas separator is fluidically coupled to the fluid inlet of the pump, and a downhole end of the fourth drive shaft is coupled to an uphole end of the third drive shaft; and
an inverted shroud assembly, wherein a downhole end of the inverted shroud assembly is coupled to an outside of the gas separator downhole of the gas phase discharge ports of the gas separator and uphole of the fluid intake;

providing electric power to the electric motor;
receiving fluid by the fluid intake from the wellbore;
flowing fluid from the fluid intake into the gas separator; separating a first portion of the fluid from a second portion of the fluid by the gas separator;
exhausting the first portion of the fluid by the gas separator out the plurality of gas phase discharge ports of the gas separator;
flowing the second portion of the fluid by the gas separator via the at least one liquid phase discharge port to the fluid inlet of the centrifugal pump;
lifting the second portion of the fluid by the centrifugal pump uphole in a production tubing coupled to an outlet of the centrifugal pump;
flowing the first portion of the fluid uphole inside the inverted shroud assembly; flowing the first portion of the fluid downhole in an annulus defined by an inside of the wellbore and an outside of the inverted shroud assembly;
bubbling gas out of the first portion of the fluid as it flows downhole in the annulus defined by an inside of the wellbore and the outside of the inverted shroud assembly to produce a third portion of the fluid, wherein the third portion of the fluid has a lower gas-to-liquid ratio than the gas-to-liquid ratio of the first portion of the fluid; and
recirculating the third portion of the fluid into the fluid intake.

12. The method of claim 11 , wherein the pump is a centrifugal pump assembly comprising a fourth drive shaft coupled to the third drive shaft.

13. The method of claim 12 , wherein the centrifugal pump assembly comprises a plurality of centrifugal pump stages.

14. The method of claim 13 , wherein each centrifugal pump stage comprises an impeller that is coupled to the fourth drive shaft and a diffuser.

15. The method of

Assignees

• Halliburton Energy Services Inc

Inventors

• Brown Donn J
• Sheth Ketankumar Kantilal
• Bernier Andre Joseph

Classifications

• E21B43/38 Primary

  in the well · CPC title

• E21B43/128 Primary

  Adaptation of pump systems with down-hole electric drives · CPC title