CA3022711A1 - In situ well completions and methods for injection and hydrocarbon recovery via single well - Google Patents

Abstract

A single-well assembly for mobilizing and recovering hydrocarbons from a single-wellbore located in a hydrocarbon-containing reservoir is described. The single-well assembly includes at least one injection sub and at least one production sub provided along a horizontal wellbore section for respectively injecting injection fluid into the reservoir and recovering production fluid from the reservoir via a corresponding port. The single-well assembly further includes an injection fluid supply system configured to transport injection fluid through each production and injection subs for injection into the reservoir via the corresponding port; and a production fluid recovery system configured to transport the production fluid flowing in the heel direction through each production and injection subs for recovery of the production fluid at surface.

Description

IN SITU WELL COMPLETIONS AND METHODS FOR INJECTION AND
HYDROCARBON RECOVERY VIA SINGLE WELL
TECHNICAL FIELD
[001] The technical field generally relates to in situ hydrocarbon recovery and, more particularly, to a single-well assembly used for hydrocarbon recovery.
BACKGROUND

[002] According to single-well steam-assisted gravity-drainage (SW-SAGD) techniques, an injection conduit and a production conduit can be located within a single well to simplify and downsize equipment. A single-well configuration can also have certain economic advantages, since the drilling, maintenance and operational costs can be reduced compared to a dual well SAGD configuration.
However, proximity of the injection conduit and the production conduit presents challenges, such as production of the injected gas phase via the production conduit.

[003] Single well configurations and equipment used in single-well operations present various drawbacks, some of which relate to fluid supply and injection, hydrocarbon production, and operating the system with simultaneous injection and production.

[004] There is thus a need for a technology that overcomes at least some of the drawbacks of what is known in the field.
SUMMARY

[005] According to an aspect, a single-well assembly for mobilizing and recovering hydrocarbons from a single-wellbore located in a hydrocarbon-containing reservoir and including a horizontal wellbore section having a toe and a heel is provided.
The single-well assembly includes at least one injection sub having an injection channel including an injection fluid inlet located on a heel side of the injection sub for receiving injection fluid flowing in a toe direction, an injection fluid outlet located on a toe side of the injection sub and in fluid communication with the injection fluid inlet for releasing injection fluid flowing in the toe direction. The injection sub further including an injection port in fluid communication with the injection channel and the reservoir to inject the injection fluid into the reservoir, and a production fluid passageway allowing passage of production fluid through the injection sub. The single-well assembly also includes at least one production sub having a production channel comprising a production fluid inlet located on a toe side of the production sub for receiving production fluid flowing in a heel direction, and a production fluid outlet on a heel side of the production sub and in fluid communication with the production fluid inlet for releasing the production fluid flowing in the heel direction.
The production sub further including a production port in fluid communication with the reservoir and the production channel to receive production fluid comprising mobilized hydrocarbons from the reservoir, and an injection fluid passageway allowing passage of injection fluid through the production sub. The single-well assembly further includes an injection fluid supply system configured to transport the injection fluid flowing in the toe direction through at least one of the production and/or injection subs for injection into the reservoir via the corresponding injection port; and a production fluid recovery system configured to transport the production fluid flowing in the heel direction through at least one of the production and/or injection subs for recovery of the production fluid at surface.

[006] According to a possible embodiment, the injection fluid supply system includes injection conduits coupled to each injection sub for connecting with corresponding adjacent production subs, the injection conduits comprising a first injection conduit coupled to the injection fluid inlet and a toe side of the injection fluid passageway of a first adjacent production sub for transporting the injection fluid therebetween; and a second injection conduit coupled to the injection fluid outlet and a heel side of the injection fluid passageway of a second adjacent production sub for transporting the injection fluid therebetween.

[007] According to another possible embodiment, the production fluid recovery system includes production conduits coupled to each production subs for connecting with corresponding adjacent injection subs, the production conduits comprising a first production conduit coupled to the production fluid outlet and a toe side of the production fluid passageway of a first adjacent injection sub for transporting the production fluid therebetween; and a second production conduit coupled to the production fluid inlet and a heel side of the production fluid passageway of a second adjacent injection sub for transporting the production fluid therebetween.

[008] According to another possible embodiment, the injection conduits of the injection fluid supply system extend within the production conduits of the production fluid recovery system.

[009] According to another possible embodiment, the first injection conduit extends within the second production conduit, and wherein the second injection conduit extends within the first production conduit.

[0010] According to another possible embodiment, the injection fluid supply system further includes at least one stabilizing conduit coupled between one of the injection conduits and the corresponding injection or production sub, the stabilizing conduit being configured to set the injection conduit within the production conduit.

[0011] According to another possible embodiment, the stabilizing conduit includes stabilizing fins extending radially and outwardly therefrom, each stabilizing fin being adapted to engage an inner surface of the corresponding production conduit.

[0012] According to another possible embodiment, the injection conduits concentrically extend within the production conduits.

[0013] According to another possible embodiment, the injection sub includes a plurality of production fluid passageways disposed about the injection channel, and wherein the production sub comprises a plurality of production channels disposed about the injection fluid passageway, each production fluid passageway being in fluid communication with a corresponding one of the production channels via the production fluid recovery system.

[0014] According to another possible embodiment, each production conduit is provided with an annular sealing element extending radially and outwardly therefrom, each annular sealing element being in sealing engagement with an inner surface of the horizontal wellbore section of the single wellbore.

[0015] According to another possible embodiment, the single-well assembly further includes a liner extending along the inner surface of the horizontal wellbore section.

[0016] According to another possible embodiment, the injection port includes at least one injection pipe extending between the injection channel and reservoir for establishing fluid communication therebetween.

[0017] According to another possible embodiment, the injection pipe includes a main injection pipe extending outwardly from the injection channel in a substantially orthogonal manner.

[0018] According to another possible embodiment, the injection pipe further includes one or more secondary injection pipes extending outwardly from the main injection pipe and being configured to inject injection fluid into the reservoir at an angle with respect to the horizontal wellbore section.

[0019] According to another possible embodiment, the secondary injection pipes are evenly spaced about the main injection pipe.

[0020] According to another possible embodiment, the secondary injection pipes include an inlet section extending from the main injection pipe, and an outlet section extending from the inlet section and being axially aligned therewith, the outlet section having a cross-sectional area greater than that of the inlet section.

[0021] According to another possible embodiment, the injection port includes nozzle inserts operatively connected within the inlet section of the secondary injection pipe, each nozzle insert having an inner channel for allowing passage of injection fluid therethrough and being configured to create a pressure drop for at least partially flashing the injection fluid during injection into the reservoir.

[0022] According to another possible embodiment, each of the nozzle inserts is a throttling valve.

[0023] According to another possible embodiment, each of the nozzle inserts is made of tungsten carbide.

[0024] According to another possible embodiment, the injection sub includes a plurality of injection ports radially spaced about the injection channel.

[0025] According to another possible embodiment, the production port is substantially parallel to the production channel and is adapted to transfer production fluid from the reservoir into the production fluid recovery system.

[0026] According to another possible embodiment, the production port includes a converging-diverging nozzle extending between a production port inlet and a production port outlet.

[0027] According to another possible aspect, there is provided a single-well assembly for mobilizing and recovering hydrocarbons from a single-wellbore provided in a hydrocarbon-containing reservoir and comprising a horizontal wellbore section having a toe and a heel, the single-well assembly comprising multiple subs connectable together in end-to-end fashion along the horizontal wellbore. The subs can comprise injection subs distributed along the horizontal wellbore in spaced-apart relation to each other and configured to allow passage of an injection fluid in a heel-to-toe direction and injection of a mobilizing fluid at respective locations along the horizontal wellbore; and production subs distributed along the horizontal wellbore in a staggered relation with respect to the injection subs and configured to allow passage of production fluid received from the reservoir in a toe-to-heel direction for production at surface. The multiple subs can each be configured to include injection fluid conduits and production fluid conduits that align when the subs are connected together in end-to-end fashion to provide fluid communication along the single-well assembly for flow of the production fluid and flow of the mobilization fluid. Thus, the production fluid conduits of adjacent subs align with each other, and injection fluid conduits of adjacent subs align with each other.

[0028] According to one embodiment, the subs can further comprise blank subs that enable neither injection into the reservoir nor production from the reservoir.
The injection fluid conduits can be tubular and positioned along a longitudinal centerline of the single-well assembly.

[0029] According to an embodiment, the subs can also comprise stabilizers configured to stabilize and support the injection fluid conduits.

[0030] According to an embodiment, the production fluid conduits can include annular portions and tubular portions. The annular portions of the production fluid conduits can be located about the injection fluid conduits, and the tubular portions of the production fluid conduits can be located in the injection subs and pass around corresponding injection ports that provide fluid communication from the injection fluid conduits into the reservoir.

[0031] According to an embodiment, the assembly also comprises annular sealing elements arranged in between production and injection locations to provide isolation therebetween. The sealing elements can allow some amount of fluid communication from the injection section into the production section via, for example, a tubular channel.

[0032] According to another aspect, there is provided a method for mobilizing and recovering hydrocarbons via a single well provided in a hydrocarbon-containing reservoir using the single-well assembly as defined above or herein. The method includes injecting a mobilizing fluid via a plurality of the injection subs into the reservoir to cause mobilization of hydrocarbons in the reservoir; and producing a production fluid comprising mobilized hydrocarbons from the reservoir via a plurality of the production subs.

[0033] In the method, the mobilization fluid can include or consist of steam, or can include or consists of solvent.

[0034] According to some embodiments, a plurality of the single wells is provided extending from a common well pad, the single wells being in horizontal spaced-apart relation with respect to each other within the reservoir.

[0035] According to some embodiments, an electric submersible pump is used in the single well to produce the production fluid to surface.

[0036] According to some embodiments, a gas lift system is used in the single well to produce the production fluid to surface.

[0037] According to some embodiments, a rod pump is used in the single well to produce the production fluid to surface.

[0038] According to some embodiments, a progressive cavity pump is used in the single well to produce the production fluid to surface.

[0039] According to some embodiments, comprising performing heating of the reservoir surrounding to the single well using a heater. The heater can be used during start-up and/or during normal operations.

[0040] According to some embodiments, the mobilization fluid is provided in the single-well assembly in liquid phase and flashes upon injection into the reservoir.

[0041] According to another aspect, there is provided a method for mobilizing and recovering hydrocarbons via a single well provided in a hydrocarbon-containing reservoir, the method comprising delivering a mobilizing fluid into a single-well assembly provided in a horizonal section of the single well, the single-well assembly including multiple subs connected together in end-to-end fashion and comprising injection subs and production subs; injecting the mobilizing fluid via a plurality of injection subs into the reservoir to cause mobilization of hydrocarbons in the reservoir; and recovering a production fluid comprising mobilized hydrocarbons from the reservoir via a plurality of the production subs; and producing the production fluid that flows through conduits provided in the subs and recovering the production fluid at surface.

[0042] According to some embodiments, the mobilization fluid comprises steam and/or solvent. Heating of the reservoir can include using a heater.

[0043] According to some embodiments, a plurality of the single wells is provided extending from a common well pad, the single wells being in horizontal spaced-apart relation with respect to each other within the reservoir.

[0044] According to some embodiments, an electric submersible pump is used in the single well to produce the production fluid to surface.

[0045] According to some embodiments, a gas lift system is used in the single well to produce the production fluid to surface.

[0046] According to some embodiments, a rod pump is used in the single well to produce the production fluid to surface.

[0047] According to some embodiments, a progressive cavity pump is used in the single well to produce the production fluid to surface.

[0048] According to some embodiments, the mobilization fluid is delivered into the single-well assembly in liquid phase and flashes upon injection into the reservoir.
BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is a transverse cut view of a single wellbore and a single-well assembly provided along a horizontal wellbore section.

[0050] Figure 2 is a transverse cut view of a section of the single-well assembly.

[0051] Figure 2A is a transverse cut view of a section of the single-well assembly shown in Figure 2, showing an injection sub and corresponding injection and production conduits.

[0052] Figure 2B is a transverse cut view of a section of the single-well assembly shown in Figure 2, showing an annular sealing element provided about a production conduit.

[0053] Figure 20 is a transverse cut view of a section of the single-well assembly shown in Figure 2, showing a production sub and corresponding injection and production conduits.

[0054] Figure 3A is a cross-sectional view of an injection sub, showing production fluid passageways surrounding an injection channel.

[0055] Figure 3B is a sectional view of the injection sub taken along cross-section lines 3B-3B of Figure 3A, showing an injection port extending from the injection channel.

[0056] Figure 4A is a cross-sectional view of a production sub, showing production channels surrounding an injection fluid passageway.

[0057] Figure 4B is a sectional view of the production sub taken along cross-section lines 4B-4B of Figure 4A, showing a production port extending from an outer surface of the production sub.

[0058] Figure 5A is a cross-sectional view of a stabilizing conduit, showing stabilizing fins surrounding an injection fluid passageway and extending therefrom.

[0059] Figure 5B is a sectional view of the stabilizing conduit taken along cross-section lines 5B-5B of Figure 5A.

[0060] Figure 6 is a transverse cut view of a section of the single-well assembly, showing a liner surrounding the production conduit and an annular sealing element provided between the liner and production conduit.

[0061] Figure 7 is a perspective view of a section of the single-well assembly, showing fluid passages provided in the annular sealing element to prevent pressure build-ups.

[0062] Figure 8A is a transverse cut view of a nozzle insert, showing an inner channel extending therethrough.

[0063] Figure 8B is a transverse cut view of a nozzle insert, showing an inner channel extending therethrough having a tapered section.

[0064] Figure 9A is a cross-sectional view of a production sub, showing production channels surrounding an injection fluid passageway.

[0065] Figure 9B is a sectional view of the production sub taken along cross-section lines 9B-9B of Figure 9A, showing a production port extending along the production port in a substantially parallel manner.
DETAILED DESCRIPTION

[0066] The present description describes single-well methods and assemblies as well as structural features thereof used in relation with hydrocarbon recovery operations. However, it should be understood that the techniques and features described herein could be used in relation to various hydrocarbon recovery methods including dual-well steam-assisted gravity drainage (SAGD), infill or step-out wells, cyclic steam stimulation (CSS) or other known recovery methods.

[0067] As will be described below in relation to various example implementations, a single-well assembly for mobilizing and recovering hydrocarbons from a single-wellbore provided in a hydrocarbon-containing reservoir is provided. The single-well assembly is configured to be installed within a horizontal wellbore section and includes at least one injection sub for injecting injection fluid into the reservoir, and at least one production sub for receiving production fluid comprising mobilized hydrocarbons from the reservoir. It should be understood that, in the context of the present disclosure, the expression "sub" refers to a division or part of an ensemble or structure. For example, the injection sub refers to a subsection of the single-well assembly used for the injection of mobilizing fluid. In some implementations, the injection and production subs can be installed in an alternating configuration along the horizontal wellbore section and are fluidly connected to one another via conduits extending therebetween. Each sub can include passageways and/or channels for allowing passage of both injection and production fluids therethrough for ultimately allowing recovery of production fluids from the single wellbore at surface. For simplicity, each conduit, channel, passageway, pipe and/or other similar components referred to in the following disclosure has a cross-section that is preferably circular, although it should be appreciated that other shapes are also possible.

[0068] In some implementations, hydrocarbons are recovered by injecting a mobilizing fluid (which can also be referred to as injection fluid) within the reservoir via the injection sub. The injection fluid then transfers thermal energy to the hydrocarbons contained in the reservoir to effectively mobilize the hydrocarbons by reducing the viscosity thereof. Hot mobilizing fluids (e.g., steam) use heat to raise the temperature of the hydrocarbons to facilitates mobilization, while other mobilizing fluids (e.g., organic solvents) can reduce viscosity by dissolving hydrocarbons into the solvent. Depending on the mobilizing fluid that is used, different viscosity-reduction mechanisms will be favored.

[0069] Mobilized fluid comprising hydrocarbons and injection fluid drains into the horizontal wellbore section and can then be produced via the production sub and recovered to the surface. It should be noted that the single-well assembly can be adapted to mobilize hydrocarbons in a surrounding region of the reservoir for ultimately producing the hydrocarbons via any suitable in situ recovery method which can be implemented using other well assemblies and configurations.

[0070] With reference to Figure 1, an implementation of a single-well assembly configured for installation within a single wellbore 12 provided in a hydrocarbon-containing reservoir (R) is illustrated. More specifically, the wellbore 12 can include a horizontal wellbore section 14 having a toe 15 and a heel 16 at respective ends thereof. It should be understood that, as used herein, the expression "toe"
refers to the end point of the horizontal wellbore section, as illustrated in Figure 1.
Therefore, expressions such as "toe side", "toe direction" and any other similar expressions should be understood as directional/orientational expressions using the toe 15 of the horizontal wellbore section 14 as reference. Similarly, the expression "heel", as used herein, refers to the beginning of the horizontal wellbore section 14, and traditionally follows the curved transition section between the horizontal and vertical sections of the wellbore 12. Therefore, expressions such as " heel side", "heel direction" and any other similar expressions should be understood as directional/orientational expressions using the heel 16 of the horizontal wellbore section 14 as reference.

[0071] Now referring to Figures 2 to 2C, in addition to Figure 1, the assembly is illustratively installed within the single wellbore 12, along the horizontal wellbore section 14. As best seen in Figure 2A, the assembly 10 can include at least one injection sub 100 in fluid communication with the reservoir (R) for injecting injection fluid into the reservoir. As mentioned above, once within the reservoir, the injection fluid mobilizes the hydrocarbons to enable their production.

[0072] Now referring more specifically to Figure 20, the assembly 10 can further include at least one production sub 200 in fluid communication with the reservoir (R) for receiving production fluids, which can include mobilized hydrocarbons and injection fluid. In some implementations, production and injections subs 100, can be alternatively installed along the horizontal wellbore section 14 to define multiple injection and production points communicating with the reservoir along the horizontal wellbore. More specifically, a first production sub 200 can be installed proximate the heel 16 of the wellbore 12, followed by a first injection sub 100, followed by a second production sub 200, and so on. However, it is appreciated that other configurations are possible when installing the subs 100, 200 of the assembly 10. For example, the first production sub 200 can be followed by a pair of injection subs 100 prior to installing the second production sub 200.
Indeed, multiple injection subs can be provided beside each other, and multiple production subs can be provided beside each other along the horizontal wellbore.

[0073] Referring more specifically to Figures 3A and 3B, an exemplary implementation of the injection sub 100 is shown. The injection sub 100 can include an injection channel 102 extending therethrough to allow passage of injection fluid during an injection phase of the hydrocarbon recovery operations. It should thus be understood that the injection channel 102 includes an injection fluid inlet provided on a heel side 103 of the injection sub, and an injection fluid outlet 102B
provided on a toe side 105 of the injection sub 100 (i.e., opposite the injection fluid inlet 102A) for respectively receiving and releasing injection fluid flowing in a toe direction. In the present implementation, the injection sub 100 further includes an injection port 104 fluidly connecting the injection channel 102 with the reservoir to allow injection of injection fluid into the reservoir in a manner that will be described further below. It should be understood that, as used herein, the expression "port"
refers to a connection between two or more components. Furthermore, the injection sub 100 can include a production fluid passageway 110 adapted to allow passage of production fluid, generally flowing in a heel direction, through the injection sub 100. It should be understood that the injection channel 102 and production fluid passageway 110 are not in fluid communication with each other, and that the injection and production fluids therefore flow along the single-well assembly 10 via separate conduits, as will be explained further below.

[0074] In some implementations, the injection sub 100 includes a plurality of production fluid passageways 110 provided about the injection channel 102 to allow the flow of production fluid flowing through the injection sub 100. The production fluid passageways 110 can be provided at regular intervals around the injection channel 102, or arranged in groups as illustrated in Figure 3A. The groups of production fluid passageways 110 are illustratively spaced from one another to allow the injection port 104 to extend therebetween so as to establish fluid communication between the injection channel 102 and the reservoir. It is appreciated that the production fluid passageways 110 can have any suitable shape, size and/or configuration extending through the injection sub 100.

[0075] Referring specifically to Figures 4A and 4B, an exemplary implementation of the production sub 200 is shown. The production sub 200 can include a production channel 202 extending therethrough to allow passage of production fluid for recovery thereof at surface. It should thus be understood that the production channel 202 includes a production fluid inlet 202A provided on a toe side 203 of the production sub, and a production fluid outlet 2026 provided on a heel side 205 of the production sub 200 (i.e., opposite the production fluid inlet 202A) for respectively receiving and releasing production fluid flowing in a heel direction so as to ultimately be recovered at surface. The production sub 200 further includes a production port 204 fluidly connecting the production channel 202 and the reservoir to allow production fluid to be received by the production port 204 from the reservoir in a manner that will be described further below.
Furthermore, the production sub 200 can include an injection fluid passageway 210 adapted to allow passage of injection fluid, generally flowing in a toe direction, through the production sub 200. It should be understood that, in a similar fashion as the injection channel 102 and production fluid passageway 110, the production channel 202 and injection fluid passageway 210 are not in fluid communication with one another.

[0076] Referring back to Figures 2 to 2C, in addition to Figure 3B, the single-well assembly 10 includes an injection fluid supply system 150 configured to transport injection fluid through the corresponding subs in order to inject injection fluid into the reservoir via the injection ports 104. In the present implementation, the injection fluid supply system 150 is configured to connect each adjacent sub 100, 200 to one another to allow effective transport of injection fluid through each sub via the corresponding injection channel 102 and/or injection fluid passageways 210, as previously described. In some implementations, the injection fluid supply system 150 includes injection conduits 152 fluidly connecting each corresponding pair of adjacent subs for transporting injection fluid therebetween. In other words, each sub (injection 100 or production 200) is respectively fluidly connected to an adjacent sub via an injection conduit 152 to allow injection fluid to flow therebetween.

[0077] In the illustrated implementation, the injection conduits 152 extend between the subs of the single-well assembly 10 in a manner such as a first injection conduit 154 extends between a corresponding injection sub 100 and a first adjacent production sub 200, and a second injection conduit 156 extends between the injection sub 100 and a second adjacent production sub 200. It should be understood that the first and second adjacent production subs 200 mentioned correspond to the production subs 200 located on either side of the corresponding injection sub 100. More specifically, the first injection conduit 154 can be coupled to the injection fluid inlet 102A of the corresponding injection sub 100 and a toe side of the injection fluid passageway 210 of the first adjacent production sub 200.

[0078] Furthermore, the second injection conduit 156 can be coupled to the injection fluid outlet 102B of the injection sub 100 and a heel side of the injection fluid passageway 210 of the second adjacent production sub 200. In some implementations, the injection conduits 152 can be coupled directly to the corresponding subs for establishing fluid communication therebetween. However, it is appreciated that the injection fluid supply system 150 can include one or more injection coupling conduits 158 configured to couple injection conduits 152 with an adjacent sub, or couple a pair of injection conduits 152 to one another between the corresponding subs. Therefore, it should be understood that the injection coupling conduits 158 can include a respective injection fluid passageway 159 for allowing the flow of injection fluid therethrough. It should be noted that the first and/or second injection conduits 154, 156 can be made of multiple injection conduits coupled to one another via injection coupling conduits 158 for transporting injection fluid between the subs of the assembly 10. It is appreciated that various configurations of the injection conduits 152 (with or without injection coupling conduits) are possible for connecting two adjacent subs together.

[0079] Still referring to Figures 2 to 2C, but also with reference to Figure 4B, the assembly 10 further includes a production fluid recovery system 250 configured to transport production fluid flowing in the heel direction so as to allow production and recovery of the production fluid at surface. It should be understood that the production fluid recovery system 250 is configured to connect each adjacent sub to effectively transport production fluid produced from the reservoir (R) via the corresponding production channel 202 and production fluid passageways 110. In some implementations, the production fluid recovery system 250 includes production conduits 252 fluidly connecting each corresponding pair of adjacent subs for transporting production fluid therebetween.

[0080] In the present implementation, the production conduits 252 extend between the subs of the single-well assembly 10 in a manner such as a first production conduit 254 extends between a corresponding production sub 200 and a first adjacent injection sub 100, and a second production conduit 256 extends between the production sub 200 and a second adjacent injection sub 100. It should be understood that the first and second adjacent injection subs mentioned above correspond to the injection subs located on either side of a corresponding production sub 200. More specifically, the first production conduit 254 can be coupled to the production fluid inlet 202A of the corresponding production sub and a toe side of the production fluid passageway 110 of the first adjacent injection sub 100.

[0081] Furthermore, the second production conduit 256 can be coupled to the production fluid outlet 202B of the production sub 200 and a heel side of the production fluid passageway 110 of the second adjacent injection sub 100. In some implementations, the production conduits 252 can be coupled directly to the corresponding subs for establishing fluid communication therebetween. However, it is appreciated that the production fluid recovery system 250 can include one or more production coupling conduits 258 configured to couple production conduits 252 with a corresponding adjacent sub, or couple a pair of production conduits to one another between the corresponding subs. Therefore, it should be understood that the production coupling conduits 258 can include production fluid passageways 259 for allowing the flow of production fluid therethrough. It is noted that the first and/or second production conduits 254, 256 can be made of multiple production conduits 252 coupled to one another via production coupling conduits 258 for transporting production fluid between the subs of the assembly 10. It is appreciated that various configurations of the production conduits 252 (with or without production coupling conduits) are possible for connecting two adjacent subs together.

[0082] As illustrated in Figures 1 to 2C, and as mentioned above, the single-well assembly 10 is configured in a manner to have the injection conduits 152 extend within the production conduits 252 along the horizontal wellbore section 14.
More specifically, in the present implementation, the first injection conduit 154 extends within the second production conduit 256, and the second injection conduit 156 extends within the first production conduit 254. Therefore, the production fluid can flow along the single-well assembly 10 in an annulus defined between the injection and production conduits 152, 252. In some implementations, the injection fluid is heated prior to being injected into the reservoir, as such the injection conduits 152 can be provided with an insulated layer to mitigate heat exchange and/or heat loss with the surrounding environment. Additionally, the injection conduits 152 can be concentrically positioned within the corresponding production conduit 252, although other configurations are possible. In some implementations, the injection fluid supply system 150 includes one or more stabilizing conduits 160 (Figure 2A) to effectively stabilize the injection conduits 152 within the corresponding production conduits 252. In other words, the stabilizing conduit 160 is configured to set the position of the injection conduit 152 it is connected to within the surrounding production conduit 252. Therefore, in the illustrated implementation, the stabilizing conduit 160 is configured to set the injection conduit 152 concentrically within the corresponding production conduit 252. The stabilizing conduit 160 can be coupled between adjacent injection conduits 152 and/or between an injection conduit 152 and an adjacent sub. As such, it should be understood that the stabilizing conduit 160 can function as an injection coupling conduit 158.

[0083] With reference to Figures 5A and 5B, and with continued reference to Figure 2, the stabilizing conduit 160 includes an injection fluid passageway 161 for allowing the flow of injection fluid therethrough. Additionally, the stabilizing conduit 160 includes one or more stabilizers, or stabilizing elements 162, configured to set the stabilizing conduit 160 and the components coupled therewith concentrically within the corresponding production conduit 252. In some implementations, the stabilizing elements 162 include stabilizing fins 163 extending outwardly and radially from an outer surface of the stabilizing conduit 160 for engaging an inner surface of the surrounding production conduit 252. The stabilizing conduit 160 can include multiple stabilizing fins 163 positioned at regular intervals about the stabilizing conduit 160, although it is appreciated that other configurations are possible. For example, and as illustrated in the implementation of Figure 5A, the stabilizing conduit 160 can include three or more stabilizing fins 163 spaced by about 120 degrees or less around the injection fluid passageway 161. In some implementations, the stabilizing fins 163 can have a substantially trapezoidal shape so as to define an elongated contact surface with the inner surface of the surrounding production conduit 252. However, it is appreciated that the stabilizing fins 163 can have any suitable number, shape and/or size configured to engage the inner surface in any suitable manner.

[0084] In an alternative implementation, another stabilizing structure can be used, such as a stabilizing ring for example, having stabilizing fins 163 extending therefrom. The stabilizing ring can be configured to be connected about a corresponding injection conduit 152 in a manner such that the stabilizing fins extend and engage the inner surface of the surrounding production conduit 252, while allowing production fluid to flow along the conduits, between the stabilizing fins 163.

[0085] Referring to Figures 1 and 6, well completion of the single wellbore 12 can include a liner 18 extending along an inner surface of the horizontal wellbore section 14. The liner 18 can extend along the full length of the horizontal wellbore section 14 (i.e., from heel 16 to toe 15) or along one or more sections thereof. The subs and conduits of the single-well assembly 10 are therefore adapted to be installed within the liner 18, in a generally concentric manner, although other configurations are possible. It is appreciated that the liner 18 can be slotted or include other types of apertures along a length thereof for allowing injection and/or production fluids to flow into and from the reservoir. In some implementations, the liner 18 is spaced from the production conduits 252 and/or subs 100, 200 extending therein so as to define an annular region (A) therebetween in which injection and/or production fluids can flow prior to being injected in the reservoir or recovered at surface. More specifically, injection fluid can be injected into the annular region via the injection port 104 prior to infiltrating the reservoir through the liner 18, while production fluid can infiltrate the annular region from the reservoir prior to being recovered via the production port 204. It should thus be appreciated that the single-well assembly 10 can be configured to create three independent flow paths for transporting fluids along the horizontal wellbore section 14. A first flow path (F1) is defined within the injection conduits 152, a second flow path (F2) is defined in the annulus between the injection and production conduits 152, 252, and a third flow path (F3) is defined in the annular region (A) between the production conduits and the liner 18 or inner surface of the horizontal wellbore section 14.

[0086] With reference to Figure 7, and with continued reference to Figure 6, the single-well assembly 10 can include annular sealing elements 20 configured for effectively sealing the annular region (A) described above along a section of the single-well assembly 10. In the present implementation, the annular sealing element 20 extends radially and outwardly from a corresponding production conduit 252 and engages the inner surface of the horizontal wellbore section (e.g., the liner 18). Furthermore, each annular sealing element 20 extends along a section of a corresponding production conduit 252 extending between two adjacent subs. Therefore, the annular sealing element 20 can define corresponding injection 22 and production 24 sections on either side thereof. More specifically, a pair of annular sealing elements 20 provided about production conduits 252 extending on either side of an injection sub 100 defines an injection section 22 therebetween.
As such, a pair of annular sealing elements 20 provided about production conduits 252 extending on either side of a production sub 200 defines a production section 24 therebetween. It should be understood that, as used herein, the injection section 22 refers to the section of the single-well assembly 10 along which injection fluid is injected into the reservoir (R). Similarly, the production section 24 refers to the section of the single-well assembly 10 along which production fluid is recovered from the reservoir (R). Furthermore, it should be noted that two or more sealing elements can be provided in series between injection and/or production subs.

[0087] In the present implementation, injection fluid is injected within the annular region (A) in the injection section 22 via the injection sub 100, prior to infiltrating into the reservoir (R). In a similar fashion, production fluid infiltrates the annular region (A) in the production section 24 prior to being recovered via the production port 204 and production fluid recovery system. It should be noted that each annular sealing element 20 effectively prevents fluid communication between injection and production fluids within a corresponding annular region (A) (i.e., along the third flow path (F3)). Additionally, and as best seen in Figure 7, the annular sealing element 20 can include at least one tubular fluid passage 21 extending therethrough for allowing fluids to flow from one side of the annular sealing element 20 to the other.
In the present implementation, the annular sealing element 20 includes a plurality of tubular fluid passages 21 provided about the production conduit 252 and extending axially across the annular sealing element 20, allowing fluids to flow from the injection section 22 to the production section 24, or vice-versa. It will be understood that the direction of the flow substantially depends on the pressure differential between the sections 22, 24 defined on either side of the annular sealing element 20. In some implementations, the tubular fluid passages 21 can be provided with a control valve to control fluid flowing from one side to the other in response to the pressure differential therebetween. The control valve can be configured to selectively open or close the tubing to avoid pressure build-ups within the single-well assembly 10 for example. It should be noted that other uses and configurations of the tubular fluid passages are possible, such as the ones described in Applicant's co-pending application titled PACKING MODULE AND
RELATED METHODS FOR RECOVERING HYDROCARBONS VIA A SINGLE
WELL , filed on October 31st, 2018.

[0088] Referring back to exemplary implementations of Figures 3A and 3B, in addition to Figure 6, in some implementations, the injection port 104 includes one or more injection pipes 106 extending between the reservoir and the injection channel 102 to establish fluid communication therebetween. More specifically, the injection pipes 106 are adapted to establish fluid communication between the injection channel 102 and the annular region (A) surrounding the injection sub and within the corresponding injection section 22. In the illustrated implementation, the injection pipes 106 include a main injection pipe 107 outwardly and radially extending from the injection channel 102 and one or more secondary injection pipes 108 extending from the main injection pipe 107 and communicating with the annular region (A) to allow injection of injection fluid therein and ultimately within the reservoir (R). The secondary injection pipes 108 are adapted to inject injection fluid within the annular region (A) at an angle with respect to the horizontal wellbore section 14, and thus with respect to the liner 18.

[0089] In some implementations, the injection fluid is injected within the annular region under pressure, therefore the injection is done at an angle to prevent and/or reduce potential damage done to surrounding components, such as the aforementioned liner 18 surrounding the injection sub 100. It should be understood that the main injection pipe 107 can also be adapted to inject injection fluid within the annular region, although in order to prevent injection fluids to flow directly on the liner 18, which can cause damages, the main injection pipe 107 is blocked and/or plugged to prevent any injection of fluids within the annular region.
It should be understood that the main injection pipe 107 initially extends between the injection channel 102 and the annular region (A) simply to facilitate manufacturing thereof. Once formed within the injection sub 100, the main injection pipe 107 is plugged, as previously mentioned, to direct the flow of injection fluid from the injection channel 102 into the secondary injection pipes 108. However, it is appreciated that the main injection pipe 107 can remain open, thus providing an injection pipe 106 providing a radial flow within the reservoir.

[0090] In some implementations, the injection sub 100 includes multiple injection ports 104 in order to increase injection rate of the injection fluid. In the present implementation, each injection sub 100 includes three injection ports 104, each having a main injection pipe 107 extending from the injection channel 102. The main injection pipes 107 can be provided at regular intervals about the injection channel 102 (e.g., spaced by about 120 degrees around the injection channel 102), although it is appreciated that other configurations are possible.

[0091] In the present implementation, the injection pipes 106 include a plurality of secondary injection pipes 108 provided about the main injection pipe 107 and extending outwardly therefrom. The secondary injection pipes 108 can be provided at regular intervals about the main injection pipe 107, although it is appreciated that other configurations are possible. In some implementations, each secondary injection pipe 108 can include an inlet section 112 and an outlet section 114 axially aligned along a length thereof between the main injection pipe 107 and the annular region (A). The inlet and outlet sections 112, 114 can have a cross-sectional area which differs from the other in order to create a pressure differential during injection of injection fluid. In other words, the cross-sectional area of the inlet section 112 can be smaller than the cross-sectional area of the outlet section 114, or vice-versa. In the present implementation, the cross-sectional area of the secondary injection pipes 108 is smaller along the inlet section 112 than along the outlet section 114. Therefore, pressure along the outlet section 114 is lower than the pressure along the inlet section 112 which can cause the injection fluid to evaporate at least partially into gaseous state (e.g., flash-evaporation) so as to facilitate infiltration within the reservoir and bitumen mobilization. In some implementations, the injection port 104 can be provided with nozzle inserts connected within the secondary injection pipes 108 to further increase the pressure differentiation between the inlet and outlet sections 112, 114.

[0092] With reference to Figures 8A and 8B, and with continued reference to Figure 3B, various implementations of the nozzle insert 120 are shown. The nozzle inserts 120 can have a substantially cylindrical insert body 121 configured to be inserted within the secondary injection pipes 108 in order to at least partially restrict the flow of fluids therethrough. More specifically, the insert body 121 can include a threaded section 122 complementary to a threaded section located within the secondary injection pipes 108, allowing the nozzle inserts 120 to be fastened within the corresponding pipes 108. However, it is appreciated that other methods of connecting the nozzle inserts 120 within the secondary injection pipes 108 are possible. For example, the nozzle inserts 120 can be inserted in the corresponding pipe via compression or interference fit, or can be machined as one piece from the same base material.

[0093] In some implementations, each nozzle insert 120 includes an inner channel 124 extending between an inner channel inlet 125 and an inner channel outlet for allowing injection fluid to flow therethrough and into the reservoir. As seen in the implementation of Figure 8A, the inner channel outlet 126 can be shaped and sized to allow insertion of a tool or tool head which can be used to screw the insert nozzle 120 within the secondary injection pipe 108. In the present implementation, the inner channel outlet 126 has a substantially hexagonal shape adapted to receive hexagonally shaped tools such as hexagonal keys or specialized screwdrivers for example. It is appreciated that the hexagonal opening can have any suitable length along the insert nozzle 120. For example, the insert nozzle 120 can simply have a hexagonal-shaped outer-flange proximate the channel outlet 126 for allowing removal, installation and/or replacement of the insert nozzle using a socket-type tool.

[0094] In addition, the inner channel 124 can be configured to create a pressure differential as the injection fluid flows through the nozzle insert 120. More specifically, the inner channel inlet 125 can have a smaller cross-sectional area than that of the inner channel outlet 126, causing a pressure-drop through the nozzle insert 120. Therefore, the pressure differential caused by the nozzle inserts 120 can contribute in flashing the injection fluid in order to facilitate infiltration into the reservoir. It is appreciated that the inner channel inlet and outlet 125, 126 can respectively have a substantially fixed cross-sectional area (Figure 8A) or have a varying (e.g., tapered) cross-sectional area (Figure 8B). In some implementations, the nozzle inserts 120 are made from hardened steel or carbide tungsten for example to withstand the high pressures as injection fluid flows therethrough.
It should be readily understood that the nozzle inserts 120 can be throttling valves configured to reduce the pressure as the injection fluid is injected into the reservoir from the injection port 104.

[0095] Referring back to exemplary implementations of Figures 4A and 4B, in addition to Figure 6, in some implementations, the production port 204 includes a production pipe 206 extending between the reservoir and the production channel 202 in order to establish fluid communication therebetween. More specifically, the production pipe 206 is configured to establish fluid communication between the annular region (A) surrounding the production sub 200 (i.e., within the production section 24) and the production channel 202. In the illustrated implementation, the production pipe 206 extends along a length between an inlet 208 and an outlet 209, with the inlet 208 communicating with the annular region (A) and the outlet 209 communicating with the production fluid inlet 202A of the production sub 200.
The cross-sectional area of the production pipe 206 can vary between the inlet and outlet 209 thereof in order to create a pressure differential during recovery of production fluids. In the present embodiment, the cross-sectional area of the production pipe 206 proximate the inlet 208 is greater than that proximate the outlet 209. In some implementations, and as illustrated in Figure 4B, the production pipe 206 can be angled with respect to the horizontal wellbore section 14 in order to facilitate entry of production fluids in the inlet 208 of the production pipe 206.
However, the angled production pipe 206 can cause production fluids to exit the outlet 209 and flow directly towards the injection conduit connected to the production fluid inlet 202A of the production sub 200. When pressurized, or when containing elements such as sand, dirt or rocks, the production fluid flowing onto the injection conduit 152 can increase wear and/or cause damages thereto.

[0096] In some implementations, and with reference to Figures 9A and 9B, in addition to Figure 4B, it is appreciated that the production pipe 206 can be substantially parallel to the horizontal wellbore section, and thus to the conduits of the single-well assembly 10. Therefore, the flow of production fluids exiting the outlet 209 is directed within the production conduit 252 away from the injection conduit 152, thus reducing and/or preventing damages. It is thus appreciated that, in the present implementation, the inlet 208 includes a recess 208A extending into the production sub 200 to allow communication with the production pipe 206. In some implementations, the production port 204 can further include a port insert 218 insertable within the production pipe 206 along a section thereof to increase the pressure differential created between the inlet 208 and outlet 209. In the present implementation, the port insert 218 includes a converging-diverging nozzle for creating the pressure differential. However, it is appreciated that other mechanisms and/or methods are possible for creating a variation in pressure along the production pipe 206. In the present implementation, the port insert 218 is introduced within the production pipe 206 mechanically via press-fit connection, although other methods of connection are possible. Furthermore, in some implementations, the production sub 200 can include multiple production ports 204, and thus more than one production pipe 206 extending therethrough, effectively increasing overall production rate of production fluids. Each production sub 200 can include three production ports 204 for example, provided at regular intervals around the injection fluid passageway 210. However, it is appreciated that other configurations are possible.

[0097] In some implementations, the production sub 200 includes a single injection fluid passageway 210 and a plurality of production channels 202 provided about the injection fluid passageway 210 for increasing the flow of production fluid flowing through the production sub 200. The production channels 202 can be provided at regular intervals around the injection fluid passageway 210, or arranged in groups as illustrated in Figures 4A and 9A. The groups of production channels 202 are illustratively spaced from one another to allow the production pipe(s) 206 to extend therebetween so as to establish fluid communication between the production channels 202 and the annular region (A). It is appreciated that the production channels 202 can have any suitable shape, size and/or configuration extending through the injection sub 100. It should be understood from the description above that the production channels 202 of each production sub 200 are in fluid communication with the production fluid passageways 110 of each injection sub 100, and that the injection channel 102 of each injection sub 100 is in fluid communication with the injection fluid passageway of each production sub 200.

[0098] It will be understood from the foregoing disclosure that various implementations of a single-well assembly adapted to enable both injection and production phases of bitumen recovery operations is provided. The single-well assembly is configured to create three independent flow paths therealong, with any two of said flow paths being able to communicate. Therefore, the single-well assembly advantageously allows for greater flow areas within a single well installation while allowing multiple flow paths which can be made to communicate with one another.

Claims (52)

27

1. A single-well assembly for mobilizing and recovering hydrocarbons from a single-wellbore provided in a hydrocarbon-containing reservoir and comprising a horizontal wellbore section having a toe and a heel, the single-well assembly comprising:
at least one injection sub comprising:
an injection channel comprising:
an injection fluid inlet located on a heel side of the injection sub for receiving injection fluid flowing in a toe direction; and an injection fluid outlet located on a toe side of the injection sub and in fluid communication with the injection fluid inlet for releasing injection fluid flowing in the toe direction;
an injection port in fluid communication with the injection channel and the reservoir to inject the injection fluid into the reservoir; and a production fluid passageway allowing passage of production fluid through the injection sub;
at least one production sub comprising:
a production channel comprising:
a production fluid inlet located on a toe side of the production sub for receiving production fluid flowing in a heel direction; and a production fluid outlet on a heel side of the production sub and in fluid communication with the production fluid inlet for releasing the production fluid flowing in the heel direction;
a production port in fluid communication with the reservoir and the production channel to receive production fluid comprising mobilized hydrocarbons from the reservoir; and an injection fluid passageway allowing passage of injection fluid through the production sub;
an injection fluid supply system configured to transport the injection fluid flowing in the toe direction through at least one production and/or injection sub for injection into the reservoir via the corresponding injection port; and a production fluid recovery system configured to transport the production fluid flowing in the heel direction through at least one production and/or injection sub for recovery of the production fluid at surface.

2. The assembly according to claim 1, wherein the injection fluid supply system comprises injection conduits coupled to each injection sub for connecting with corresponding adjacent production subs, the injection conduits comprising:
a first injection conduit coupled to the injection fluid inlet and a toe side of the injection fluid passageway of a first adjacent production sub for transporting the injection fluid therebetween; and a second injection conduit coupled to the injection fluid outlet and a heel side of the injection fluid passageway of a second adjacent production sub for transporting the injection fluid therebetween.

3. The single-well assembly according to claim 1 or 2, wherein the production fluid recovery system comprises production conduits coupled to each production sub for connecting with corresponding adjacent injection subs, the production conduits comprising:
a first production conduit coupled to the production fluid outlet and a toe side of the production fluid passageway of a first adjacent injection sub for transporting the production fluid therebetween; and a second production conduit coupled to the production fluid inlet and a heel side of the production fluid passageway of a second adjacent injection sub for transporting the production fluid therebetween.

4. The single-well assembly according to claim 3, wherein the injection conduits of the injection fluid supply system extend within the production conduits of the production fluid recovery system.

5. The single-well assembly according to claim 4, wherein the first injection conduit extends within the second production conduit, and wherein the second injection conduit extends within the first production conduit.

6. The single-well assembly according to claim 4 or 5, wherein the injection fluid supply system further comprises at least one stabilizing conduit coupled between one of the injection conduits and the corresponding injection or production sub, the stabilizing conduit being configured to set the injection conduit within the production conduit.

7. The single-well assembly according to claim 6, wherein the stabilizing conduit comprises stabilizing fins extending radially and outwardly therefrom, each stabilizing fin being adapted to engage an inner surface of the corresponding production conduit.

8. The single-well assembly according to any one of claims 4 to 7, wherein the injection conduits concentrically extend within the production conduits.

9. The single-well assembly according to any one of claims 1 to 8, wherein the injection sub comprises a plurality of production fluid passageways disposed about the injection channel, and wherein the production sub comprises a plurality of production channels disposed about the injection fluid passageway, each production fluid passageway being in fluid communication with a corresponding one of the production channels via the production fluid recovery system.

10. The single-well assembly according to any one of claims 3 to 9, wherein each production conduit comprises an annular sealing element extending radially and outwardly therefrom, each annular sealing element being in sealing engagement with an inner surface of the horizontal wellbore section of the single wellbore.

11. The single-well assembly according to claim 9, further comprising a liner extending along the inner surface of the horizontal wellbore section.

12. The single-well assembly according to any one of claims 1 to 10, wherein the injection port comprises at least one injection pipe extending between the injection channel and reservoir for establishing fluid communication therebetween.

13. The single-well assembly according to claim 12, wherein the injection pipe comprises a main injection pipe extending outwardly from the injection channel in a substantially orthogonal manner.

14. The single-well assembly according to claim 13, wherein the injection pipe further comprises one or more secondary injection pipes extending outwardly from the main injection pipe and being configured to inject injection fluid into the reservoir at an angle with respect to the horizontal wellbore section.

15. The single-well assembly according to claim 14, wherein the secondary injection pipes are evenly spaced about the main injection pipe.

16. The single-well assembly according to claim 14 or 15, wherein the secondary injection pipes comprise an inlet section extending from the main injection pipe, and an outlet section extending from the inlet section and being axially aligned therewith, the outlet section having a cross-sectional area greater than that of the inlet section.

17. The single-well assembly according to claim 16, wherein the injection port comprises nozzle inserts operatively connected within the inlet section of the secondary injection pipe, each nozzle insert having an inner channel for allowing passage of injection fluid therethrough and being configured to create a pressure drop for at least partially flashing the injection fluid during injection into the reservoir.

18. The single-well assembly according to claim 17, wherein each of the nozzle inserts is a throttling valve.

19. The system according to claim 17 or 18, wherein each of the nozzle inserts is made of tungsten carbide.

20. The single-well assembly according to any one of claims 1 to 19, wherein the injection sub comprises a plurality of injection ports radially spaced about the injection channel.

21. The single-well assembly according to any one of claims 1 to 20, wherein the production port comprises a converging-diverging nozzle extending between a production port inlet and a production port outlet.

22. The single-well assembly according to any one of claims 1 to 21, comprising multiple injection subs and multiple production subs.

23. The single-well assembly according to claim 22, wherein the injection fluid supply system is configured to transport the injection fluid flowing in the toe direction through each production and injection sub for injection into the reservoir via corresponding injection ports.

24. The single-well assembly according to claim 23, wherein the production fluid recovery system is configured to transport the production fluid flowing in the heel direction through each production and injection sub for recovery of the production fluid at surface.

25.A single-well assembly for mobilizing and recovering hydrocarbons from a single-wellbore provided in a hydrocarbon-containing reservoir and comprising a horizontal wellbore section having a toe and a heel, the single-well assembly comprising:
multiple subs connectable together in end-to-end fashion along the horizontal wellbore, the subs comprising:
injection subs distributed along the horizontal wellbore in spaced-apart relation to each other and configured to allow passage of an injection fluid in a heel-to-toe direction and injection of a mobilizing fluid at respective locations along the horizontal wellbore; and production subs distributed along the horizontal wellbore in a staggered relation with respect to the injection subs and configured to allow passage of production fluid received from the reservoir in a toe-to-heel direction for production at surface; and wherein the multiple subs each are configured to include injection fluid conduits and production fluid conduits that align when the subs are connected together in end-to-end fashion to provide fluid communication along the single-well assembly for flow of the production fluid and flow of the mobilization fluid.

26. The single-well assembly according to claim 25, wherein the subs further comprise blank subs that enable neither injection into the reservoir nor production from the reservoir.

27.The single-well assembly according to claim 25 or 26, wherein the injection fluid conduits are tubular and are positioned along a longitudinal centerline of the single-well assembly.

28.The single-well assembly according to any one of claims 25 to 27, wherein the subs further comprise stabilizers configured to stabilize and support the injection fluid conduits.

29.The single-well assembly according to any one of claims 25 to 28, wherein the production fluid conduits comprise annular portions and tubular portions.

30.The single-well assembly according to claim 29, wherein the annular portions of the production fluid conduits are located about the injection fluid conduits, and the tubular portions of the production fluid conduits are located in the injection subs and pass around corresponding injection ports that provide fluid communication from the injection fluid conduits into the reservoir.

31. The single-well assembly according to any one of claims 25 to 30, further comprising annular sealing elements arranged in between adjacent production and/or injection locations to provide isolation therebetween.

32.A method for mobilizing and recovering hydrocarbons via a single well provided in a hydrocarbon-containing reservoir using the single-well assembly as defined in claims 1 to 31, the method comprising:
injecting a mobilizing fluid via a plurality of the injection subs into the reservoir to cause mobilization of hydrocarbons in the reservoir; and producing a production fluid comprising mobilized hydrocarbons from the reservoir via a plurality of the production subs.

33. The method of claim 32, wherein the mobilization fluid comprises steam.

34. The method of claim 32 or 33, wherein the mobilization fluid comprises or consists of solvent.

35. The method of any one of claims 32 to 34, wherein a plurality of the single wells is provided extending from a common well pad, the single wells being in horizontal spaced-apart relation with respect to each other within the reservoir.

36. The method of any one of claims 32 to 35, wherein an electric submersible pump is used in the single well to produce the production fluid to surface.

37. The method of any one of claims 32 to 35, wherein a gas lift system is used in the single well to produce the production fluid to surface.

38. The method of any one of claims 32 to 35, wherein a rod pump is used in the single well to produce the production fluid to surface.

39. The method of any one of claims 32 to 35, wherein a progressive cavity pump is used in the single well to produce the production fluid to surface.

40. The method of any one of claims 32 to 39, wherein the mobilization fluid is provided in the single-well assembly in liquid phase and flashes upon injection into the reservoir.

41. The method of any one of claims 32 to 40, further comprising performing heating of the reservoir surrounding to the single well using a heater.

42.A method for mobilizing and recovering hydrocarbons via a single well provided in a hydrocarbon-containing reservoir, the method comprising:
delivering a mobilizing fluid into a single-well assembly provided in a horizonal section of the single well, the single-well assembly including multiple subs connected together in end-to-end fashion and comprising injection subs and production subs;

injecting the mobilizing fluid via a plurality of injection subs into the reservoir to cause mobilization of hydrocarbons in the reservoir;
recovering a production fluid comprising mobilized hydrocarbons from the reservoir via a plurality of the production subs; and producing the production fluid that flows through conduits provided in the subs and recovering the production fluid at surface.

43. The method of claim 42, wherein the single-well assembly is as defined in any one of claims 1 to 31.

44. The method of claim 42 or 43, wherein the mobilization fluid comprises steam.

45. The method of any one of claims 42 to 44, wherein the mobilization fluid comprises or consists of solvent.

46. The method of any one of claims 42 to 45, further comprising performing heating of the reservoir surrounding to the single well using a heater.

47. The method of any one of claims 42 to 46, wherein a plurality of the single wells is provided extending from a common well pad, the single wells being in horizontal spaced-apart relation with respect to each other within the reservoir.

48. The method of any one of claims 42 to 47, wherein an electric submersible pump is used in the single well to produce the production fluid to surface.

49. The method of any one of claims 42 to 47, wherein a gas lift system is used in the single well to produce the production fluid to surface.

50. The method of any one of claims 42 to 47, wherein a rod pump is used in the single well to produce the production fluid to surface.

51. The method of any one of claims 42 to 47, wherein a progressive cavity pump is used in the single well to produce the production fluid to surface.

52. The method of any one of claims 42 to 51, wherein the mobilization fluid is delivered into the single-well assembly in liquid phase and flashes upon injection into the reservoir.