WELL SYSTEM AND METHOD FOR CONTROLLING THE PRODUCTION OF FLUIDS

Abstract

Embodiments of the present invention allow the placement of a stand alone device (valve) along a flow path, without a physical connection to the surface or reliance on the borehole for signaling, to provide a means to control the flow between reservoirs. This is achieved using a valve located in the flow path that can be actuated without sending signals down the borehole or well path and thereby eliminating the need for complicated signal lines and or fluid columns to actuate the valve.

Description

FIELD OF THE INVENTION

The present invention relates to methods and devices for recovering fluids from subterranean formations, and in particular, a system and a method for recovering hydrocarbons by means of individual or multi-lateral wells drilled to connect a distant reservoir to a subsurface zone.

BACKGROUND

It is generally known that methods for drilling wells close to another originate from the practice of drilling relief wells or the practice of field redevelopment where a second or third generation of drilling from existing well stock is required to enhance the recovery of the nearby oil or gas. Methods for drilling multiple wells which increase production from one well without injection from other wells have been proposed before.

U.S. Pat. No. 6,729,394 and U.S. Pat. No. 6,119,776 are examples of this. U.S. Pat. No. 6,729,394 describes the use of a horizontal well network for producing low mobility oil, where at least one horizontal well is used as to allow fluids to move from one part of the producing formation to another and closer to the final production well. U.S. Pat. No. 6,119,776 describes the use of an intersecting angled and vertical well, in which the vertical well being used to withdraw the fluid that was originally contained in the angled well, combined with the optional use of a third well from which fractures are generated to the second well. However, practice of the methods and system disclosed by the foregoing art can be expensive and often requires the employment of relatively complicated procedures.

The prior art does not use multiple wells to produce from one hydrocarbon reservoir to another, but instead uses the reservoir length as a purposeful flow path. Furthermore, existing flow control devices (e.g., valves) use the well to transmit a signal along the borehole. However, controlling the flow between different reservoirs is still evolving and one aspect that can be improved is communication to a flow control device that has been along the wellbore. The purpose of the flow control is to block unwanted fluids, such as water, gas, or oil, from coming to surface. Methods like 4-D seismic and others to detect the encroachment of such fluids already exist. Because of various drawbacks with designs that are well-known in the art, it is not desirable to send signals along the borehole to the flow control device. Embodiments of the present invention address the known deficiencies for communicating with a valve along the borehole and, as such, do not require the wellbore as the signal path.

SUMMARY OF THE INVENTION

In accordance with various embodiments of the present invention the primary reservoir is connected to the marginal reservoir either by drilling a bridging well adjutant to the primary well or extending the primary well. A downhole production system for producing and controlling hydrocarbon from primary and marginal reservoir,

In accordance with various embodiments of the present invention, a downhole production system comprises a wireless transmitter that transmits a wireless signal through the formation from a location external to the borehole. A valve is located along a flow path between two reservoirs. A sensor is adjacent to the valve and capable of detecting the wireless signal, wherein the valve is actuated in response to the detection of the wireless signal by the signal detector.

Certain embodiments of a method for actuating a flow control devise comprise several steps, which are as follows: (i) placing a flow control device between two reservoirs; (ii) transmitting a signal from a surface location to a borehole through a strata; (iii) detecting the signal; (iv) communicating to the flow control device in a preset coded sequence adapted to actuate the valve; and (v) actuating the flow control device when the sensor receives the signal.

Moreover, embodiments of a method of producing subterranean hydrocarbons comprises of the following steps: (i) drilling and completing a primary well for producing a primary reservoir; (ii) drilling at least one auxiliary well adjacent to the primary well; (iii) connecting the primary reservoir to the marginal reservoir by extending the primary well; (iv) completing the primary well to control fluid communication between the primary reservoir and the marginal reservoir; and (v) placing a flow control device along a flow path between the primary reservoir and the marginal reservoir.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a sectional view of a well with multiple producing intervals in sequence and a means to communicate to a valve located between the reservoirs without using the borehole.

FIG. 2 illustrates wellbores intersecting a plurality of production zones.

FIG. 3 is a sectional view similar to FIG. 2, but illustrating an alternate flow control valve.

FIG. 4 is a sectional view similar to FIG. 3, but illustrating a flow control valve in a well requiring sand control.

FIG. 5 shows a schematic diagram of a multi-zone sand face completion requiring more than one flow control valve and a communication line and cable.

FIG. 6 shows a schematic illustration of a sectional view of a multi-lateral wellbore with a plurality of production zones.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to provide an understanding of the present invention. However, it is to be understood by those skilled in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.

In the specification and appended claims: the terms “connect”, “connection”, “connected”, “in connection with”, and “connecting” are used to mean “in direct connection with” or “in connection with via another element”; and the term “set” is used to mean “one element” or “more than one element”. As used herein, the terms “up” and “down”, “upper” and “lower”, “upwardly” and downwardly”, “upstream” and “downstream”; “above” and “below”; and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some embodiments of the invention. Moreover, the term “sealing mechanism” includes: packers, bridge plugs, downhole valves, sliding sleeves, baffle-plug combinations, polished bore receptacle (PBR) seals, and all other methods and devices for temporarily blocking the flow of fluids through the wellbore.

An embodiment of the present invention provides a system and method for controlling the flow of fluids that migrate through the subsurface from a distant marginal reservoir to one or more production zones of the primary reservoir. The method of producing subterranean hydrocarbons comprises of drilling and completing a primary well for producing a primary reservoir. At least one well adjacent to the primary well will also be drilled. The primary reservoir is then connected to the marginal reservoir by extending the primary well. With reference now to the figures, and in particular to FIG. 1, a well (3) with producing interval (4) connects separate hydrocarbon intervals (5, 6) below the surface (1) to the surface facilities (2). According to the invention, a flow control device (e.g., a sleeve valve, ball valve, flapper valve, disk valve, choke valve and so forth) (7) is placed between the intervals (4, 5 and 6) that can be used to close off flow between the intervals without any physical connections to the surface. The migration of fluid from one interval to the next can effectively drain the produced fluid without having to drill a separate well from surface and still maintain control of the movement from the one interval to the next. While certain embodiments are described herein, for subsea operation, the present invention includes other embodiments employing the same systems and methods for land use.

In this embodiment, with reference to FIGS. 1 and 2, the flow control device (14) can be placed along the flow path in the casing (13) between two or more reservoirs, In the open state, the flow control device allows the fluids from one reservoir (4, 5, 6) to flow into a different reservoir (4, 5, 6) until such time as the operator decides it is time to stop the flow or choke the flow between the reservoirs. In this application, it can also allow the purposeful drilling of a well to connect one side of a reservoir (5) to a second nearby reservoir (6) and subsequent plugging and abandoning of the upper section to surface of the subject well thus only contain the flow in the subsurface between the two reservoirs (5 and 6). This then provides an enhanced flow path between reservoirs. The flow control device (14) placed along the flow path can be actuated later in the life of the field to shut off or choke the flow between the reservoirs. In one embodiment the flow control device (14) is a stand alone device with no physical connection to the surface and no reliance on the wellbore to detect a signal. This would eliminate the need for signal lines and/or fluid columns to actuate the valve. This in turn, yields a significant reduction of installation costs, thus reducing the cost of the development of the reservoir or field.

With reference to FIG. 1, many signals (8) that are sent from surface are transmitted subsurface through the strata (29). The signals (8) can be used to communicate to the flow control device (7) in a pre-set coded sequence that once understood by the flow control device (7) can actuate the flow control device (14) to open or close or choke position. In some embodiments, a wellbore is not needed to transmit the signals to actuate the flow control device (7).

Referring to FIGS. 2 through 6, an existing well (3) has a producing interval (10) with a casing (13) and a production conduit (15). In one embodiment a sand screen (17) is provided within each of the intervals (10, 11, 12) allowing fluids to be produced while preventing sand to enter the production tubing. The production intervals are separating fluidically by sealing elements (16). Alternately a slotted pipe is provided in place of screen. Yet in another embodiment the hole is lined with casing or liner, cemented and perforated.

According to the invention, a second well (9) is drilled into another reservoir that is positioned further from the surface facilities. A well may be drilled through the wellhead (28) and through a formation to extend a structural casing (13) through the formation. A new well (9) is drilled to connect the bypassed marginal reservoir (11) to the existing reservoir (10). A casing (13) is run to the top of the formation. The second well (9) is plugged using a sealing element (18) above the formation interval (11) to provide a barrier. The sealing element may either be permanent, or such that the well can be reentered at a latter time should it be necessary.

The reservoir (11) through the new well (9) is produced through the sand face completion and then injected into the existing reservoir (10).

In the example in FIG. 2, a ball type flow control valve (14) is run with the well completion to regulate the flow from the reservoir (11) to the existing reservoir (10). Referring to FIG. 3, a sleeve type flow control valve (19) is run with the well completion. Referring to FIG. 4, the sleeve type flow control valve (19) is incorporated in the sand screen (17). FIGS. 2 through 6 illustrate a sensor module (20) that is shown in the valve (14 and 19) to actuate the valve.

In some embodiments of the present invention, the power to the flow control valve (14, 19) and downhole sensors (20) is supplied by a downhole power generator (21) which is run with the valve. A remote coded signal or command is sent from the surface. A long life battery, fuel cell or other type of power supply could be run in place of downhole power generator (such as an inline turbine).

Depending on the particular embodiment of the invention, electromagnetic communication, acoustic communication, pressure pulse, electronic signal communication in or along the casing or tubing, mud pulse communication, or seismic communication may be used. Thus, many different communication techniques may be used to communicate between the surface and the valve, in accordance with the possible embodiments of the invention. For example, an acoustic wave transmitter used in a wellbore typically will generate compressional waves, shear waves, and other types of waves when the acoustic transmitter is actuated. The compression wave is refracted in the formation surrounding the borehole and propagates through a portion of the formation surrounding the borehole. The acoustic wave is then reflected or partially reflected from the formation into the sensor, which detects and measures the acoustic wave by two or more receivers. The sensor (20) in the valve (14, 19) first detects this signal and then the signal is processed by microprocessor in the valve and sent to valve actuator for actuation of the valve. Many signals that are sent from surface through the subsurface and rock strata can be used to communicate to the valve (14,19) in a preset coded sequence that once understood by the valve (14,19) can actuate the device to open or close or choked position.

An alternate embodiment of a method for sending signals from the surface to actuate the valve would require the downhole sensors to sense various reservoir parameters such as pressure, flow, temperature, fluid density, fluid viscosity, or PH, and feeds the data to the downhole processor which processes the data and makes a logical decision to send a proper command to the valve actuator for actuating the valve. A well bore is not needed to transmit the signals to actuate the valve. It is in this way that the well design and related components as well as the operations related to installation can be reduced.

Some alternate embodiments comprise wired communication to the flow control valve and sensor module. Referring to FIGS. 5 and 6, a communication line (e.g., an electric cable, a hydraulic control line, a pneumatic control line, a fiber optic cable, etc.) (22) from the flow control valve and sensor module (23) is run to the surface and then connected to the existing infrastructure (24). For example, the flow control valve is actuated by means of a communication line such as an electrical control line conveying electric signals, a hydraulic line conveying pressurized fluid, or a pneumatic control line containing an electrical conductor conveying pressure and electrical signals. The communication line (22) supplies power and/or communication to the valve from surface. A coiled tubing, small macaroni tubing, drill pipe, tubing, or umbilical hose bundle (25) could be used for conveying the cable and control line and/or actuating the valve. A communication line (22) is run from the valve to the surface for supplying power and communication to the valve from the surface. As an alternate embodiment, the communication line can supply communication to the valve from the surface location with a power supply (e.g. long life battery or fuel cell) in the well to provide power to the valve.

Depending on the sand face completion (e.g. cased & perforated, stand alone screen, expandable screen, pre packed screen, slotted pipe, open hole) the flow control valve, sand face completion, and cable can be run in a single run on coiled tubing, pipe, or tubing (25). In a completion requiring two trips such as a frac pack completion or a gravel pack, a wet connect could be provided in the lower completion for connecting the communication line from the surface. FIGS. 2 through to 6 show multi-zone sand face completions that require more than one flow control valve.

As illustrated in FIG. 6, a multi-lateral well (26) has at least one branch to connect more than one reservoir (23 and 27) to the existing reservoir (10).

While the invention has been disclosed with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations there from. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of the invention.

Claims

1. A downhole completion system comprising: wherein the flow control device is actuated in response to the detection of the wireless signal by the sensor, and wherein the wireless signal is transmitted through a strata between the surface location and the subsurface location.

a wireless transmitter that transmits a wireless signal from a surface location to a subsurface location;

a flow control device located along a flow path between two reservoirs proximate the subsurface location;

a sensor adjacent to the flow control device adapted to detect the wireless signal,

2. The downhole system of claim 1, wherein the sensor and flow control valve are supplied with power from a downhole power supply.

3. The downhole system of claim 1, wherein the sensor and flow control valve are supplied with power from a downhole power generator.

4. The downhole system of claim 1, wherein the flow control device is connected with a communication line running from the surface location, and wherein the communication line is adapted to supply the flow control device with power.

5. The downhole system of claim 1, wherein the flow control device is a flow control valve, and wherein the wireless transmitter transmits a signal that is in a preset coded sequence that will actuate the valve.

6. The downhole system of claim 1, wherein the wireless transmitter transmits a signal that is in a preset coded sequence that will actuate the flow control device to open or close.

7. A method for actuating a flow control device, comprising:

placing a flow control device between two reservoirs;

transmitting a signal from a surface location to a borehole through a strata;

detecting the signal;

communicating to the flow control device in a preset coded sequence adapted to actuate the valve; and

actuating the flow control device when the sensor receives the signal.

8. The method of claim 7, wherein the signal from the surface location to actuate the flow control device is at least one selected from the group consisting of: seismic, acoustic, pressure pulse, mud pulse and electromagnetic.

9. The method of claim 7, further comprising actuating the flow control device requiring

the sensor to sense reservoir parameters and feed data to a downhole processor that sends a command to the flow control device to actuate the valve.

10. The method of claim 7, further comprising supplying power to the flow control device from a battery or a fuel cell that is run with the flow control device.

11. The method of claim 7, further comprising supplying power to the flow control device from a downhole power supply.

12. The method of claim 11, wherein the downhole power supply comprises a downhole power generator.

13. A method of producing subterranean hydrocarbons comprising of:

drilling and completing a primary well for producing a primary reservoir;

drilling at least one auxiliary well adjacent to the primary well;

connecting the primary reservoir to the marginal reservoir by extending the primary well;

completing the primary well to control fluid communication between the primary reservoir and the marginal reservoir; and

placing a flow control device along a flow path between the primary reservoir and the marginal reservoir.

14. A method of claim 13 further comprising placing a sensor adjacent to the flow control device.

15. The method of claim 13, further comprising actuating the flow control device via a cable or a control line from a surface location.

16. A method of claim 13 wherein the primary reservoir is connected to the marginal reservoir by drilling and completing a multilateral bridging well proximate the primary well.

17. The method of claim 13, further comprising regulating flow of the fluid between the marginal reservoir and the primary reservoir with the flow control device.

18. The method of claim 13, further comprising supplying power to the flow control device and downhole sensor using a downhole power supply.

19. The method of claim 14, further comprising detecting a wireless signal using the sensor, wherein the flow control device is actuated in response to the wireless.

20. The method of claim 15, wherein the step of actuating the flow control device via a cable or a control line from a surface location is at least one step selected from the group consisting of using an electrical control line to convey electric signals, using a hydraulic control line to convey pressurized fluid, using a pneumatic control line containing an electrical conductor to convey pressure and electrical signals.