US-12618316-B2 - Downhole sand trap

US12618316B2US 12618316 B2US12618316 B2US 12618316B2US-12618316-B2

Abstract

A solids trap module for an electrical submersible pump (ESP) of a wellbore is provided. The module includes a solids buffer and a fluid passage, the fluid passage having a first segment configured to redirect a fluid in a first angular direction relative to an axial axis, and a second segment configured to redirect at least a portion of the redirected fluid flow in a second angular direction different than the first angular direction. The first segment, the second segment, and the solids buffer are configured to cooperate to cause settling of solids entrained by the fluid flowing through the solids trap module during a period when the ESP does not operate and to re-entrain settled solids into the fluid flowing through the solids trap module when the ESP is operating.

Inventors

Rae Andrew Younger
Richard Mark Pye
Christopher Wrighton

Assignees

SAUDI ARABIAN OIL COMPANY

Dates

Publication Date: 20260505
Application Date: 20221213

Claims (12)

1 . A solids trap module for an electrical submersible pump (ESP) of a wellbore, comprising: a body; a flow modifier configured to be a solid obstruction positioned axially within the body and statically affixed to the body via one or more ribs or spokes, wherein an uphole-facing surface of the flow modifier forms a solids buffer, wherein the flow modifier is in the form of a rounded cone, an apex of the rounded cone having a spherical cap positioned downhole and a base of the rounded cone forming the solids buffer; and a fluid passage defined by an inner surface of the body and an outer surface of the flow modifier, the fluid passage comprising: a first segment configured to redirect a fluid flowing through the solids trap module in a first angular direction relative to an axial axis of the solids trap module to form a redirected fluid flow; and a second segment, fluidly connected to the first segment, configured to redirect at least a portion of the redirected fluid flow in a second angular direction different than the first angular direction to pass over at least a portion of the solids buffer, wherein, when the ESP is not operating, the first segment, the second segment, the body, and the flow modifier are configured to cooperate to cause settling of solids entrained by the fluid onto the solids buffer of the flow modifier as the fluid flows downhole through the solids trap module, and wherein, when the ESP is operating, the first segment, the second segment, the body, and the flow modifier are configured to cooperate to cause the solids settled on the solids buffer to be re-entrained into the fluid as the fluid flows uphole through the solids trap module.
2 . The solids trap module of claim 1 , wherein a first cross-sectional area of the second segment at a first point nearest the axial axis of the solids trap module is smaller than a second cross-sectional area of the second segment at a second point furthest from the axial axis of the solids trap module.
3 . The solids trap module of claim 1 , wherein a first cross-sectional area of the first segment at a first point nearest the axial axis of the solids trap module is greater than a second cross-sectional area of the first segment at a second point furthest from the axial axis of the solids trap module.
4 . The solids trap module of claim 1 , wherein the solids buffer comprises a recess configured to accumulate settled solids.
5 . The solids trap module of claim 1 , wherein the one or more ribs or spokes affix the rounded cone to the inner surface of the solids trap module.
6 . The solids trap module of claim 5 , wherein at least one of the one or more ribs or spokes are configured to impart rotation to the fluid flowing through the solids trap module.
7 . The solids trap module of claim 1 , wherein a first external surface of the solids trap module is configured to engage with a second external surface of a second solids trap module to enable stacking of the solids trap module with another solids trap module.
8 . The solids trap module of claim 7 , wherein the solids trap module comprises a first register having a complementary shape to a register of the second solids trap module, and configured to concentrically align the solids trap module with the second solids trap module in a stacked configuration.
9 . The solids trap module of claim 1 , wherein the solids trap module comprises a geometric feature configured to angularly align the solids trap module with another solids trap module.
10 . The solids trap module of claim 1 , wherein the solids trap module is unitarily formed by one of casting, injection molding, and three-dimensional printing.
11 . A wellbore, comprising: a one-way flapper valve; the solids trap module according to claim 1 positioned uphole of a one way flapper valve.
12 . The wellbore according to claim 11 , further comprising: an electric submersible pump located down hole of the solids trap module.

Description

BACKGROUND Various techniques for bringing liquids out of a subterranean wellbore to the surface of the Earth may be implemented, for example, artificial lift technology. Artificial lift technology may include, for example, a pump and associated components to assist in lifting the fluids up through the wellbore. As an example, production tubing associated with the wellbore may include one or more pumps to assist in lifting the fluids up the wellbore. The pump may be electrically operated and located submerged in the fluid at or near the bottom of the well. The pump system may use a surface or seabed power source to drive the submerged pump assembly. Alternatively, power for the pump may be provided at another location downhole in the well, such as a downhole fuel cell. These pump systems so configured are termed electric submersible pump (ESP) systems. Fluid pumped through a wellbore may also contain suspended solids (e.g., sand, scale, and other solid media), which may be entrained in the fluid flow and lifted to the surface along with the pumped fluid. However, in certain circumstances, the solids may fall back towards the ESP, for example, when the operation of the ESP is interrupted. Solids within the unpumped fluid may fall out of suspension (e.g., due to gravity acting on the particles), and reverse flow may also occur when the fluid column ‘back-flows’ or reverse-drives the unpowered ESP. This may cause the fluid column to flow back through the ESP. The mass flow rate of fluid falling back through the unpowered ESP might be a fraction of the mass flow rate when the ESP is operating under power—the falling column of back-flowing fluid is moving slower than when the fluid is pumped by the ESP to surface, thereby further causing solids to settle out of the fluid and fall toward the ESP. Solids arriving at the ESP may sufficiently accumulate to block or otherwise impede the ESP when pumping resumes. If sufficient solids accumulate then the ESP may become inoperable, potentially entraining expensive remedial repair. Some well systems have implemented passive and/or active mechanisms two attempt to limit or stop solids from arriving at the ESP. However, in such systems, the solids falling out of suspension in the stationary fluid column may ultimately impede operation of the mechanism intended to prevent the solids from reaching the ESP, thereby entraining additional cost to repair the mechanism. SUMMARY This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. In one aspect, embodiments disclosed herein relate to a solids trap module for an electrical submersible pump (ESP) of a wellbore. The solids trap module includes a solids buffer and a fluid passage having a first segment configured to redirect a fluid flowing through the solids trap in a first angular direction relative to an axial axis of the solids trap to form a redirected fluid flow, and a second segment configured to redirect at least a portion of the redirected fluid flow in a second angular direction different than the first angular direction to pass over at least a portion of the solids buffer. The first segment, the second segment, and the solids buffer are configured to cooperate to cause settling of solids entrained by the fluid flowing through the solids trap module during a period when the ESP does not operate and to re-entrain settled solids into the fluid flowing through the solids trap when the ESP is operating. A first cross-sectional area of the second segment at a first point nearest the axial axis of the solids trap module may be smaller than a second cross-sectional area of the second segment at a second point furthest from the axial axis of the solids trap module. A first cross-sectional area of the first segment at a first point nearest the axial axis of the solids trap module may be greater than a second cross-sectional area of the first segment at a second point furthest from the axial axis of the solids trap module. The solids buffer may include a recess configured to accumulate settled solids. The fluid passage may be defined by an inner surface of the solids trap module and an outer surface of a rounded cone having a spherical cap, and wherein a base of the rounded cone forms the solids buffer. The solids trap module may include one or more spokes affixing the rounded cone to the inner surface of the solids trap module. At least one of the one or more spokes may be configured to impart rotation to the fluid flowing through the solids trap module. An external surface of the solids trap module may be configured to engage with an external surface of a second solids trap module to enable stacking of the solids trap module with another solids trap module. The solids trap mo