Reusable compression barge with jack-up mechanism

Abstract

Compression barges may comprise a buoyant, vertically translatable platform; one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed; a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from a wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the natural gas. During use, the compression barges may be transported or propelled from one wellhead platform to another.

Description

REUSABLE COMPRESSION BARGE WITH JACK-UP MECHANISMFIELD

[0001] The present disclosure relates to natural gas extraction operations, and, more particularly, to compression systems for end-of-life reservoirs.BACKGROUND

[0002] During the extraction of natural gas and other hydrocarbons from subterranean reservoirs, the flow of hydrocarbons into a wellbore may be controlled by a pressure differential between the reservoir and the wellbore flowpath. The weight and flow of fluids within the wellbore flowpath exert a back-pressure on the reservoir, such that the hydrocarbons will only flow into the wellbore flowpath while the reservoir pressure overcomes this back-pressure. While the hydrocarbons stored in the pores of the reservoir naturally pressurize the reservoir, the reservoir pressure will gradually decrease as the hydrocarbons are extracted through the wellbore. The reduction of wellbore back-pressure may thus enable additional hydrocarbons to be extracted from the reservoir, as the back-pressure may be similarly reduced to enable continued flow even at reduced reservoir pressures. As such, methods and systems have been developed to reduce the wellbore back-pressure exerted on the subterranean reservoir during drilling and extraction of hydrocarbons.

[0003] For offshore natural gas reservoirs, pressures within these reservoirs are commonly at or around about 180 barg prior to extraction operations. Extraction operations are performed using offshore natural gas wellhead platforms to control the flow of pressurized natural gas from the reservoirs via a wellbore drilled into the seabed. These offshore wellhead platforms may be used in standard operation for extracting the pressurized natural gas until reservoir pressures have dropped to around about 80 barg. This 80 barg threshold is commonly utilized in the transport of liquified natural gas (LNG) via trains and pipelines, and may represent a desired minimum pressure to be maintained within the wellbore. Once the natural gas reservoir drops below this 80 barg threshold, pressure supplementation may be utilized at the offshore wellhead platform to increase the production pressures back above this threshold.

[0004] Compression systems may be utilized to compress extracted gas at a wellhead of the wellbore to reduce the back-pressure exerted on the reservoir. These compression systems may become increasingly important for weaker reservoirs, or partially depleted reservoirs, which may exhibit reduced reservoir pressures. Accordingly, compression systems may be installed nearer toan end of the service lifetime of a wellbore or reservoir, such that an increased portion of the remaining stranded hydrocarbons may be extracted. Difficulties may arise, however, for offshore hydrocarbon production facilities, as there may be significant costs and environmental impacts associated with installing a permanent compression system and corresponding structure for an aging wellbore. While current practices focus on the reduction of stranded hydrocarbons left within operational wellbores, the cost associated with adding compression to remote, offshore wellhead platforms may outweigh the benefit of the increased production.

[0005] As such, cost-effective compression systems and methods for use thereof for offshore natural gas wellhead platforms are desirable.SUMMARY OF INVENTION

[0006] In various aspects, the present disclosure provides compression barges comprising: a buoyant, vertically translatable platform; one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed; a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from a wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the extracted gas.

[0007] In some or other various aspects, the present disclosure provides methods comprising: transporting a compression barge to a location near a wellhead platform, the compression barge comprising: a buoyant, vertically translatable platform, one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed, a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from the wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the extracted gas. The provided methods further comprise: lowering the one or more legs into contact with the seabed and embedding the one or more legs into the seabed; actuating the jacking system to raise the buoyant,vertically translatable platform off of a water surface; performing a tie-in of the compression system of the compression barge with the wellhead platform to provide fluid and electrical communication between the wellhead platform and the compression system; and reducing the back-pressure exerted by the wellhead platform on the reservoir providing the extracted gas through compression of downstream fluids or gases via the compression system, thereby increasing production of the reservoir.

[0008] In further various aspects, the present disclosure provides systems comprising: a wellhead platform installed at an offshore location above a wellbore extending into a reservoir for producing natural gas therefrom; a compression barge for reducing a back-pressure exerted on the reservoir, the compression barge comprising: a buoyant, vertically translatable platform, one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed, a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization, and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from the wellhead platform to reduce a back-pressure exerted by the wellhead platform upon the reservoir providing the natural gas; and a bridge extending between the wellhead platform and the compression barge once in a raised state, the bridge providing a path for components comprising one or more of piping, tubing, electrical connections, instrumentation cables, or any combination thereof.

[0009] These and other features and attributes of the disclosed apparatuses, systems, and methods of the present disclosure and their advantageous applications and / or uses will be apparent from the detailed description which follows.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] To assist those of ordinary skill in the relevant art in making and using the subject matter hereof, reference is made to the appended drawings. The following figures are included to illustrate certain aspects of the disclosure, and should not be viewed as exclusive configurations. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and having the benefit of this disclosure.

[0011] FIG. 1 is a schematic view of a wellhead platform installed at an offshore location above a wellbore for the production of natural gas from a reservoir.

[0012] FIG. 2 is an isolated schematic view of a compression barge and a compression system, according to one or more embodiments consistent with the present disclosure.

[0013] FIG. 3 is an example method for reducing a back-pressure exerted on a reservoir using a compression barge.DETAILED DESCRIPTION

[0014] The present disclosure relates to natural gas extraction operations, and, more particularly, to compression systems for end-of-life reservoirs.

[0015] The presently disclosed subject matter relates to reusable, mobile compression systems for temporary deployment to a wellhead platform. As discussed above, pressure supplementation may be utilized at the wellhead platform to increase the production pressures back above the 80 barg threshold. However, as further natural gas is extracted from the reservoir, the pressures within the reservoir will continue to decrease until a lower limit of profitability is reached. In conventional systems, economic feasibility of continued operation of wellhead platforms can end at around about 30 barg reservoir pressures. Past this point, the cost of equipment and operation needed to maintain operational pressures can exceed the potential earnings of any further extracted natural gas. Specifically, while extraction operations could continue past this 30 barg cutoff pressure to enable an additional 5-10 years of possible extraction operations, a separate compression system may be needed to extend the production lifetime. These separate compression systems conventionally require the construction of permanent structures appended to the wellhead platform to house the components of the compression system. The construction costs and environmental impacts associated with these permanent structures may be key considerations for an economic feasibility analysis for continued operations of a wellhead platform.

[0016] As a solution to the foregoing issues, the present disclosure provides systems and methods utilizing compression barges which are deployable to remote, offshore wellhead platforms. The disclosed compression barges may include a plurality of legs that may be lowered into the water near the wellhead platform and embedded into the sea floor. The compression barge may be accordingly raised, or “jacked-up” on the embedded legs to bring the buoyant, vertically translatable platform out of the water and to the height of the wellhead platform. A compression system present on the compression barge may be tied into the production system of the wellheadplatform, such that the compression system may lower the back-pressure exerted on the reservoir (e. ., by the wellhead platform) to enhance extraction efficiency. The compression barges disclosed herein can accordingly extend the lifetime of the reservoir and enable the economical extraction of natural gas down to a reservoir pressure of about 10 barg to about 20 barg.

[0017] Following the enhanced extraction and end-of-life activities of the active reservoir using the compression barge, the buoyant, vertically translatable platform may be lowered down the legs and back into the water. The legs of the compression barge may be extracted from the sea floor and stowed on the compression barge for transport. The compression barge may then be towed or otherwise propelled (transported) to another wellhead platform to reduce back-pressure exerted on a further reservoir. As such, the disclosed compression barges and methods of use may be reusable, exist as a temporary structure, and provide a reduced environmental footprint when compared to permanent structures. Using the disclosed compression barges and methods of use, offshore wellhead platforms can remain profitable for their remaining 5-10 years of life without installation of permanent capital equipment at the offshore wellbore platform, while the costs of the compression system are recouped through the relocation and reuse of the compression barge after these 5-10 years have elapsed. Thus, the disclosed compression barges and methods for use thereof may significantly reduce the cost associated with reducing back-pressure exerted on a reservoir, while extending the lifetime of a deployed compression system.

[0018] FIG. 1 is a schematic view of a wellhead platform 100 installed at an offshore location above a wellbore 102 for the production of natural gas from a reservoir (not shown). Wellbore 102 may exert a back-pressure on the reservoir, such that the flow of natural gas therefrom is reduced or ceased. In some embodiments, operations of wellhead platform 100 (hereinafter, “platform 100”) and wellbore 102 may exert a significant back-pressure on the reservoir, leaving a substantial amount of hydrocarbons stranded within the reservoir. This back-pressure can be a result of the hydrostatic pressure of fluids within the wellbore and tubing, which can become greater than a pressure of the reservoir during extraction. The difference between the reservoir pressure and the back-pressure is accordingly reduced over time, leading to decreased production rates, and eventual cessation of flow from the reservoir. As such, in the present disclosure, compression barge 104 is provided at a location near platform 100 to provide back-pressure reduction. Compression barge 104 may include a buoyant, vertically translatable platform 106 (hereinafter, “buoyant platform 106”) that may provide sufficient buoyancy in the water to transport compression barge104 and any included components to platform 100. In some embodiments, compression barge 104 may be transported (e.g., towed or otherwise propelled) to the illustrated location.

[0019] Compression barge 104 may further include a plurality of legs 108 operable to extend below buoyant platform 106 and into the seabed upon reaching platform 100. While four legs 108 are depicted in a rectangular pattern in FIG. 1, legs 108 may be provided in a variety of numbers and configurations on buoyant platform 106 to maintain stability of compression barge 104. Legs 108 may include seabed feet 110 that may be embedded into the seabed near platform 100 to anchor and stabilize compression barge 104 in place. Seabed feet 110 may be provided in a variety of configurations, including, but not limited to, spudcan and matt footing designs. Spudcan footing designs may provide individual seabed feet 110 for each leg 108, with each spudcan footing including a conical projection on an underside thereof for penetrating into the seabed and providing stability for each leg 108. In contrast, seabed feet 110 with a matt footing design may provide a single, flat surface that extends between each leg 108 to provide a large surface area upon which legs 108 are collectively supported against the seabed. The design of seabed feet 110 can be chosen to optimize stability for buoyant platform 106 based upon the number of legs 108, the presence of obstacles on the seabed, and the composition, geometry, and strength of the seabed at the desired location.

[0020] A jacking system of legs 108 may be actuated (“jacked-up”) to raise buoyant platform 106 out of the water and to a height at or near that of platform 100. In some embodiments, the jacking system for legs 108 can include a rack and pinion mechanism operable to progressively raise buoyant platform 106 vertically on legs 108 using stationary racks provided on legs 108 without slippage. In further embodiments the jacking system for legs 108 can include a hydraulic system operable to extend a piston or ram to elevate buoyant platform 106 before locking in place and retracting the piston or ram. In these embodiments, the repeated raising, locking, and retracting can enable buoyant platform 106 to be raised on legs 108 to a desired height. The jacking system for legs 108 may be a permanent component installed on compression barge 104, or may be a retractable and portable jacking system removably coupled to legs 108. The use of a retractable and portable jacking system may enable the jacking system to be reused on further compression barges 104 and other jack-up platforms, such that costs and operational expenditures may be minimized. In some embodiments, the jacking system for raising buoyant platform 106 on legs108 may be powered by an external power source that may be deployed to compression barge 104 during jack-up operations.

[0021] Compression barge 104 may include a compression system 112 installed at least in part upon a top surface of buoyant platform 106 and operable to reduce the back-pressure exerted by platform 100 and wellbore 102 on the reservoir. As depicted in FIG. 1, platform 100 and compression barge 104 may be connected via a bridge 114 to enable personnel of platform 100 to access compression system 112. Bridge 114 may further provide secure paths for piping, tubing, electrical connections, instrumentation cables, and other connective components to extend between platform 100 and compression system 112 above the water. Bridge 114 may be integral to the compression barge 104 depending on the available clearance between platform 100 and buoyant platform 106 or the available clearance between the feet of the skirt pile of platform 100 and seabed feet 110 of compression barge 104. In some embodiments, bridge 114 is constructed between compression barge 104 and platform 100 after raising buoyant platform 106 on legs 108. In these embodiments, the connections for the piping, tubing, electrical connections, and instrumentation cables can be semi-permanent, such that these connections are welded connections for long-term use. In further embodiments, however, these connections may be flanged connections to enable rapid connection and disconnection during the deployment of compression barge 104.

[0022] Compression system 112 may be tied into platform 100 and any production systems thereon, such that compression system 112 may be utilized in reducing back-pressure exerted on the reservoir. The tie-in process can include the activation of connections installed on bridge 114, such that compression system 112 and platform 100 are placed in active fluid and electrical communication for active operation of compression system 112. Compression system 112 can introduce compression to downstream gas flow to pull extracted gas and fluids away from wellbore 102, such that lower quantities of fluids are retained within wellbore 102 and tubing included therein to reduce the back-pressure exerted on the reservoir. The compression provided by compression system 112 may accordingly reduce surface pressure of platform 100 to decrease bottomhole flowing pressures, thus increasing gas velocity and production rates within wellbore 102. The increased gas velocity may further surpass a critical velocity at which liquid droplets will flow upward, thus alleviating liquid-loading problems and increasing the efficiency of both gas production and liquid transport to the surface. As this critical velocity is directly proportional tothe surface pressure at platform 100, compression system 112 may be designed and sized to correspond to critical velocity calculations. Compression system 112 may reduce the backpressure as low as economically feasible to capture a portion of the stranded hydrocarbons remaining within the reservoir, while further enabling the rate of liquid removal from the extracted natural gas via the reduced surface pressure.

[0023] In some embodiments, compression barge 104 and compression system 112 may be unmanned and operated remotely. In these embodiments, compression barge 104 may be communicatively coupled with an onshore control center (not shown) via a fiber optic cable or other connection, including a non-wired connection. The fiber optic cable may be used for remote operation of compression system 112 from the onshore control center, preventing a need for operators to be present on compression barge 104 during operation and natural gas extraction.

[0024] In other embodiments, the compression barge 104 may have an onboard crew during navigation to platform 100 and / or operation of compression system 112.

[0025] Following depletion of the reservoir at the lower back-pressure value, compression system 112 may be disconnected from platform 100, and bridge 114 may be accordingly raised away from compression barge 104 (e.g., via a crane boat) to enable relocation. In some embodiments, a tripod or other central support may be provided below bridge 114 prior to disconnection to maintain structural integrity of bridge 114 after relocation of compression barge 104. The tripod may be placed below bridge 114 during installation thereof. Buoyant platform 106 may be lowered back down legs 108 and into the water, and seabed feet 110 may be disengaged from the seabed to enable translation or other movement of legs 108. Legs 108 may be retracted vertically towards buoyant platform 106, such that compression barge 104 is free to be transported (e.g., towed or otherwise propelled) to another offshore wellhead platform for further backpressure reduction operations. In some embodiments, compression barge 104 may be provided without a navigation system onboard, and may be transported via tugs to reach further offshore wellhead platforms. The relocation of compression barge 104 may accordingly extend the lifetime of compression barge 104 and compression system 112 through multiple uses on multiple offshore wellhead platforms, spreading the cost across several operations and increasing an overall life cycle of compression system 112 when compared to permanent structures.

[0026] FIG. 2 is an isolated schematic view of compression barge 104 and compression system 112, according to one or more embodiments consistent with the present disclosure. Compressionsystem 112 may include a primary compressor 202 operable to compress extracted gas of platform 100 (FIG. 1), such that the back-pressure exerted on the reservoir may be reduced. Primary compressor 202 may be driven electrically or run on fuel gas, depending on the infrastructure available on platform 100 of FIG. 1. In some embodiments, platform 100 (FIG. 1) may include, or be otherwise coupled to, a fuel gas subsea ring that may provide fuel gas to primary compressor 202. The operational flexibility of powering primary compressor 202 through electrical or fuel gas means may enable deployment of compression barge 104 in various conditions without retrofitting compression system 112. Compression system 112 may further include one or more turbines 204, or motors, operable to provide power to the primary compressor 202 to enable continuous compression on the compression barge 104. To enable the continuous compression, compression system 112 may utilize sea water to extract excess heat from a cooling medium of compression system 112 in a cooling cycle. Accordingly, a plurality of sea water lift pumps 206 may extend, vias caissons, from compression barge 104 into the water below.

[0027] Sea water lift pumps 206 may pump sea water vertically upward toward compression system 112, and into a sea water / fresh water heat exchanger 208. Sea water / fresh water heat exchanger 208 may exchange heat from the cooling medium of compression system 112 with the pumped sea water, such that heat may be removed from the cooling medium and into the pumped sea water. In some embodiments, the cooling medium of compression system 112 may be fresh water included within compression system 112 to reduce metallurgy costs for components of compression system 112.

[0028] The cooling medium (e.g., fresh water) can be routed through compression system 112 via a plurality of cooling medium circulation pumps 210, which provide a flowrate of the cooling medium to compression system 112 at a desired rate for dissipating the heat generated from compression. Cooling medium circulation pumps 210 may provide the cooling medium to coolers 212 that may include suction, interstage, and discharge coolers for the compression system 112. Further, cooling medium circulation pumps 210 may provide the cooling medium to cooling medium expansion tank 214. Compression barge 104 may further include a flare knockout drum 216 thereon, such that flare knockout drum 216 may be used to direct relief gases, such as during operational upsets, to a flare system (not shown) that is located on platform 100 (FIG. 1). In further embodiments, however, compression barge 104 and compression system 112 may be providedwithout flare knockout drum 216, or a flare system, without departing from the scope of the present disclosure.

[0029] FIG. 3 is an example method 300 for reducing a back-pressure exerted on a reservoir via a compression barge (e.g., compression barge 104). Method 300 may begin at 302 with transporting, towing, or propelling a compression barge to an underproducing wellhead platform (e.g, platform 100). At 302, a buoyant platform (e.g, buoyant platform 106) of the compression barge may be towed or otherwise propelled to the location of the underproducing wellhead platform to temporarily provide a compression system (e.g., compression system 112) to said wellhead platform. In some embodiments, the underproducing wellhead platform may exert a back-pressure on the reservoir of a magnitude greater than or equal to the reservoir pressure, thus reducing or ceasing flow of hydrocarbons.

[0030] Method 300 may continue at 304 with lowering and embedding one or more legs (e.g, legs 108) from the buoyant platform into the seabed below. At 304, the legs may be lowered towards the seabed until one or more seabed feet (e.g, seabed feet 110) are embedded within the seabed to provide stability to the compression barge. Upon embedding the legs and / or seabed feet into the seabed, method 300 may continue at 306 with jacking-up the buoyant platform vertically up the legs of the compression barge. The jacking-up at 306 may raise the buoyant platform and compression system to a height of the wellhead platform, thus enabling connection and travel between the wellhead platform and the compression barge. Method 300 may then continue at 308 with installing a bridge (e.g, bridge 114) spanning between the raised compression barge and the underproducing wellhead platform. The bridge may include secure paths for piping, tubing, electrical connections, instrumentation cables, and other connective components. The bridge can serve as a semi-permanent connection between the temporary compression barge and permanent wellhead platform, and can be removably coupled to the compression barge for later removal during relocation.

[0031] Method 300 may continue at 310 with performing a tie-in of the compression system of the compression barge with the underproducing wellhead platform by use of the installed bridge. The compression system may be connected directly to a wellhead or multiple wellheads of the wellbore (<?.g., wellbore 102) to provide compression to the extracted natural gas. During this tie- in, a first section of piping extending from the wellhead platform and a second section of piping extending from the compression barge may be mated or otherwise connected on the installedbridge. In some embodiments, the first section and second section may be mated via a flanged connection, such that these sections may be removably coupled to enable rapid disengagement during relocation of the compression barge. In further embodiments, however, these sections may be welded together on the installed bridge for semi-permanent use of the compression barge. In these embodiments, during relocation of the compression barge, the welded connection may be cut to enable decoupling of the compression barge from the wellhead platform.

[0032] Method 300 may continue at 312 with reducing the back-pressure exerted by the wellhead platform on the reservoir. The reduction of back-pressure at 312 may be directly performed by the compression system, such that compressing the extracted gas (e.g., natural gas) at the wellhead platform will reduce the back-pressure to enhance production. As such, this reduction of backpressure at 312 may resume or enhance the flow of natural gas out of the reservoir. The backpressure may be continuously reduced at 312 until the reservoir is sufficiently tapped of stranded hydrocarbons, or until the wellhead platform is abandoned. In some embodiments, this sufficient tapping of stranded hydrocarbons can be measured based upon pressures within the reservoir, such that the compression system and compression barge can be used with the wellhead platform until the reservoir pressures reach from about 10 barg to about 20 barg.

[0033] After the reservoir is considered tapped, or the wellhead platform is abandoned, method 300 may then continue at 314 with disconnecting the compression system from the wellhead platform and raising the bridge away from the compression barge. As discussed above, the compression system may be disconnected through the separation of a flanged connection or the cutting of a welded connection between a first piping section and a second piping section of the piping spanning across the installed bridge. In some embodiments, prior to raising the bridge away from the compression barge, a tripod or other central support may be installed below the bridge, such that the bridge may be supported following removal of the compression barge from the wellhead platform. The tripod may be placed below the bridge during installation thereof. In further embodiments, however, the bridge may be self-supporting, such that no further infrastructure is utilized to maintain bridge placement after removal of the compression barge. Once the compression system has been disconnected from the wellhead platform, the bridge may be lifted away from the compression platform to enable relocation of the compression barge without interference. In some embodiments, a crane boat may be utilized to lift the bridge away from the compression barge and the wellhead platform to complete this disconnection process.

[0034] Method 300 may then continue at 316 with lowering the compression barge vertically down the legs until the buoyant platform reaches the surface of the water. The legs of the compression barge may be retracted at 316, such that the compression barge may become mobile and ready for further towing or transporting. As such, in some embodiments, method 300 may continue at 302 with towing or propelling the compression barge to a new, underproducing wellhead platform. In these embodiments, the compression barge and compression system may be reusable across multiple wellhead platforms, as the compression barge provides a mobile, temporary structure to aid in the extraction of natural gas or other hydrocarbon resource. Method 300 may then cyclically continue for the lifetime of the compression barge, such that a plurality of wellhead platforms may be enhanced, and multiple reservoirs may be tapped of stranded hydrocarbons by a single compression barge.Additional Embodiments

[0035] The present disclosure is further directed to the following non-limiting embodiments.

[0036] Embodiment 1. A compression barge comprising: a buoyant, vertically translatable platform; one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed; a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from a wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the extracted gas.

[0037] Embodiment 2. The compression barge of Embodiment 1, wherein the back-pressure exerted upon the reservoir, after compression of the extracted gas by the compression system, enables gas extraction at a reservoir pressure of about 10 barg to about 20 barg.

[0038] Embodiment 3. The compression barge of Embodiment 1 or Embodiment 2, further comprising: a seabed foot on each of the one or more legs configured for embedment into the seabed to anchor and stabilize the compression barge.

[0039] Embodiment 4. The compression barge of Embodiment 3, wherein the seabed foot is a spudcan design or a matt footing design.

[0040] Embodiment 5. The compression barge of any one of Embodiments 1-4, wherein the jacking system is removably coupled to the one or more legs.

[0041] Embodiment 6. The compression barge of any of Embodiments 1-5, wherein the jacking system includes a rack and pinion mechanism or a hydraulic ram mechanism for raising the buoyant, vertically translatable platform.

[0042] Embodiment 7. A method comprising: transporting a compression barge to a location near a wellhead platform, the compression barge comprising: a buoyant, vertically translatable platform, one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed, a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from the wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the extracted gas; lowering the one or more legs into contact with the seabed and embedding the one or more legs into the seabed; actuating the jacking system to raise the buoyant, vertically translatable platform off of a water surface; performing a tie-in of the compression system of the compression barge with the wellhead platform to provide fluid and electrical communication between the wellhead platform and the compression system; and reducing the back-pressure exerted by the wellhead platform on the reservoir providing the extracted gas through compression of downstream fluids or gases via the compression system, thereby increasing production of the reservoir.

[0043] Embodiment 8. The method of Embodiment 7, further comprising: installing a bridge between the compression barge and the wellhead platform after actuating the jacking system, the bridge providing a path for components comprising one or more of piping, tubing, electrical connections, instrumentation cables, or any combination thereof.

[0044] Embodiment 9. The method of Embodiment 7 or Embodiment 8, further comprising: ceasing production of the extracted gas from the reservoir upon reaching a desired, lower reservoir pressure; raising, via a crane boat, the bridge away from the compression barge and the wellhead platform to enable lowering of the buoyant, vertically translatable platform; lowering the buoyant, vertically translatable platform down the one or more legs onto the water surface; disengaging theone or more legs from the seabed; and transporting the compression barge to another wellhead platform for further operation.

[0045] Embodiment 10. The method of Embodiment 9, wherein the desired, lower reservoir pressure ranges from about 10 barg to about 20 barg.

[0046] Embodiment 11. The method of Embodiment 9 or Embodiment 10, further comprising: disconnecting a flanged connection provided on the bridge between the wellhead platform and the compression barge to disconnect fluid communication therebetween prior to raising the bridge away from the compression barge and the wellhead platform.

[0047] Embodiment 12. The method of any of Embodiments 9-11, wherein the extracted gas is received by the compression system for about 5 years to about 10 years prior to raising the bridge away from the compression barge and wellhead platform.

[0048] Embodiment 13. The method of any one of Embodiments 7-12, wherein the compression system is operated remotely via a fiber optic cable communicatively coupling the compression barge with an onshore control center.

[0049] Embodiment 14. The method of any one of Embodiments 7-13, wherein lowering the one or more legs into contact with the seabed comprises lowering the legs until one or more seabed feet of the one or more legs are embedded within the seabed.

[0050] Embodiment 15. The method of any one of Embodiments 7-14, further comprising: uncoupling the jacking system from the one or more legs and the buoyant, vertically translatable platform after raising the buoyant, vertically translatable platform off of the water surface.

[0051] Embodiment 16. A system comprising: a wellhead platform installed at an offshore location above a wellbore extending into a reservoir for producing natural gas therefrom; a compression barge for reducing a back-pressure exerted on the reservoir, the compression barge comprising: a buoyant, vertically translatable platform, one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed, a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization, and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from the wellhead platform to reduce a back-pressure exerted by the wellhead platform upon the reservoir providing the natural gas; and a bridgeextending between the wellhead platform and the compression barge once in a raised state, the bridge providing a path for components comprising one or more of piping, tubing, electrical connections, instrumentation cables, or any combination thereof.

[0052] Embodiment 17. The system of Embodiment 16, further comprising: a first piping section extending from the wellhead platform to the bridge and a second piping section extending from the compression barge to the bridge, the first and second piping sections extending along the path of the bridge.

[0053] Embodiment 18. The system of Embodiment 17, wherein a flanged connection is provided between the first piping section and the second piping section.

[0054] Embodiment 19. The system of any one of Embodiments 16-18, wherein the one or more legs are retractable toward the buoyant, vertically translatable platform and stowable on the buoyant, vertically translatable platform.

[0055] Embodiment 20. The system of any one of Embodiments 16-19, wherein the bridge is retractable or removable from the wellhead platform and the compression barge.

[0056] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the present specification and associated claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the incarnations of the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claim, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0057] One or more illustrative incarnations incorporating one or more disclosure elements are presented herein. Not all features of a physical implementation are described or shown in this application for the sake of clarity. It is understood that in the development of a physical embodiment incorporating one or more elements of the present disclosure, numerous implementation-specific decisions must be made to achieve the developer’s goals, such as compliance with system-related, business-related, government-related, and other constraints, which vary by implementation and from time to time. While a developer’s efforts might be time-consuming, such efforts would be, nevertheless, a routine undertaking for those of ordinary skill in the art and having benefit of this disclosure.

[0058] While compositions and methods are described herein in terms of “comprising” various components or steps, the compositions and methods can also “consist essentially of’ or “consist of’ the various components and steps.

[0059] Therefore, the present disclosure is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular examples and configurations disclosed above are illustrative only, as the present disclosure may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative examples disclosed above may be altered, combined, or modified and all such variations are considered within the scope and spirit of the present disclosure. The description illustratively disclosed herein suitably may be practiced in the absence of any element that is not specifically disclosed herein and / or any optional element disclosed herein. While compositions and methods are described in terms of “comprising,” “containing,” or “including” various components or steps, the compositions and methods can also “consist essentially of’ or “consist of’ the various components and steps. All numbers and ranges disclosed above may vary by some amount. Whenever a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within the range is specifically disclosed. In particular, every range of values (of the form, “from about a to about b,” or, equivalently, “from approximately a to b,” or, equivalently, “from approximately a-b”) disclosed herein is to be understood to set forth every number and range encompassed within the broader range of values. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee. Moreover, the indefinite articles “a” or “an,” as used in the claims, are defined herein to mean one or more than one of the element that it introduces.

Claims

CLAIMSThe invention claimed is:

1. A compression barge comprising: a buoyant, vertically translatable platform; one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed; a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from a wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the extracted gas.

2. The compression barge of claim 1, wherein the back-pressure exerted upon the reservoir, after compression of the extracted gas by the compression system, enables gas extraction at a reservoir pressure of about 10 barg to about 20 barg.

3. The compression barge of claim 1 or claim 2, further comprising: a seabed foot on each of the one or more legs configured for embedment into the seabed to anchor and stabilize the compression barge.

4. The compression barge of claim 3, wherein the seabed foot is a spudcan design or a matt footing design.

5. The compression barge of any one of claims 1-4, wherein the jacking system is removably coupled to the one or more legs.

6. The compression barge of any of claims 1-5, wherein the jacking system includes a rack and pinion mechanism or a hydraulic ram mechanism for raising the buoyant, vertically translatable platform.

7. A method comprising: transporting a compression barge to a location near a wellhead platform, the compression barge comprising: a buoyant, vertically translatable platform, one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed, a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization; and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from the wellhead platform to reduce a back-pressure exerted by the wellhead platform upon a reservoir providing the extracted gas; lowering the one or more legs into contact with the seabed and embedding the one or more legs into the seabed; actuating the jacking system to raise the buoyant, vertically translatable platform off of a water surface; performing a tie-in of the compression system of the compression barge with the wellhead platform to provide fluid and electrical communication between the wellhead platform and the compression system; and reducing the back-pressure exerted by the wellhead platform on the reservoir providing the extracted gas through compression of downstream fluids or gases via the compression system, thereby increasing production of the reservoir.

8. The method of claim 7, further comprising: installing a bridge between the compression barge and the wellhead platform after actuating the jacking system, the bridge providing a path for components comprising one ormore of piping, tubing, electrical connections, instrumentation cables, or any combination thereof.

9. The method of claim 7 or claim 8, further comprising: ceasing production of the extracted gas from the reservoir upon reaching a desired, lower reservoir pressure; raising, via a crane boat, the bridge away from the compression barge and the wellhead platform to enable lowering of the buoyant, vertically translatable platform; lowering the buoyant, vertically translatable platform down the one or more legs onto the water surface; disengaging the one or more legs from the seabed; and transporting the compression barge to another wellhead platform for further operation.

10. The method of claim 9, wherein the desired, lower reservoir pressure ranges from about 10 barg to about 20 barg.

11. The method of claim 9 or claim 10, further comprising: disconnecting a flanged connection provided on the bridge between the wellhead platform and the compression barge to disconnect fluid communication therebetween prior to raising the bridge away from the compression barge and the wellhead platform.

12. The method of any of claims 9-11, wherein the extracted gas is received by the compression system for about 5 years to about 10 years prior to raising the bridge away from the compression barge and wellhead platform.

13. The method of any one of claims 7-12, wherein the compression system is operated remotely via a fiber optic cable communicatively coupling the compression barge with an onshore control center.

14. The method of any one of claims 7-13, wherein lowering the one or more legs into contact with the seabed comprises lowering the legs until one or more seabed feet of the one or more legs are embedded within the seabed.

15. The method of any one of claims 7-14, further comprising: uncoupling the jacking system from the one or more legs and the buoyant, vertically translatable platform after raising the buoyant, vertically translatable platform off of the water surface.

16. A system comprising: a wellhead platform installed at an offshore location above a wellbore extending into a reservoir for producing natural gas therefrom; a compression barge for reducing a back-pressure exerted on the reservoir, the compression barge comprising: a buoyant, vertically translatable platform, one or more legs installed on at least an underside of the buoyant, vertically translatable platform that are vertically translatable to stabilize the buoyant, vertically translatable platform against a seabed, a jacking system interposing the buoyant, vertically translatable platform and the one or more legs and operable to raise the buoyant, vertically translatable platform on the one or more legs after stabilization, and a compression system installed on at least a topside of the buoyant, vertically translatable platform and operable to receive and compress an extracted gas from the wellhead platform to reduce a back-pressure exerted by the wellhead platform upon the reservoir providing the natural gas; and a bridge extending between the wellhead platform and the compression barge once in a raised state, the bridge providing a path for components comprising one or more of piping, tubing, electrical connections, instrumentation cables, or any combination thereof.

17. The system of claim 16, further comprising: a first piping section extending from the wellhead platform to the bridge and asecond piping section extending from the compression barge to the bridge, the first and second piping sections extending along the path of the bridge.

18. The system of claim 17, wherein a flanged connection is provided between the first piping section and the second piping section.

19. The system of any one of claims 16-18, wherein the one or more legs are retractable toward the buoyant, vertically translatable platform and stowable on the buoyant, vertically translatable platform.

20. The system of any one of claims 16-19, wherein the bridge is retractable or removable from the wellhead platform and the compression barge.

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