US20160138595A1 - Subsea fluid processing system with intermediate re-circulation - Google Patents
Subsea fluid processing system with intermediate re-circulation Download PDFInfo
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- US20160138595A1 US20160138595A1 US14/686,897 US201514686897A US2016138595A1 US 20160138595 A1 US20160138595 A1 US 20160138595A1 US 201514686897 A US201514686897 A US 201514686897A US 2016138595 A1 US2016138595 A1 US 2016138595A1
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- pump
- fluid
- liquid phase
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- conduit
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- 238000012545 processing Methods 0.000 title claims abstract description 32
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- 239000007789 gas Substances 0.000 claims abstract description 28
- 239000007792 gaseous phase Substances 0.000 claims abstract description 22
- 238000004519 manufacturing process Methods 0.000 claims description 42
- 239000007788 liquid Substances 0.000 claims description 26
- 238000002347 injection Methods 0.000 claims description 12
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- 238000000034 method Methods 0.000 claims description 11
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- 238000011144 upstream manufacturing Methods 0.000 claims description 5
- 230000001276 controlling effect Effects 0.000 claims description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 12
- 229930195733 hydrocarbon Natural products 0.000 description 12
- 150000002430 hydrocarbons Chemical class 0.000 description 12
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- 239000010779 crude oil Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
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Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/01—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells specially adapted for obtaining from underwater installations
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D3/00—Axial-flow pumps
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/34—Arrangements for separating materials produced by the well
- E21B43/36—Underwater separating arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D13/00—Pumping installations or systems
- F04D13/02—Units comprising pumps and their driving means
- F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
- F04D13/08—Units comprising pumps and their driving means the pump being electrically driven for submerged use
- F04D13/10—Units comprising pumps and their driving means the pump being electrically driven for submerged use adapted for use in mining bore holes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
- F04D15/0005—Control, e.g. regulation, of pumps, pumping installations or systems by using valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
- F04D15/0027—Varying behaviour or the very pump
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
- F04D15/0072—Installation or systems with two or more pumps, wherein the flow path through the stages can be changed, e.g. series-parallel
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D17/00—Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps
- F04D17/08—Centrifugal pumps
- F04D17/10—Centrifugal pumps for compressing or evacuating
- F04D17/12—Multi-stage pumps
- F04D17/14—Multi-stage pumps with means for changing the flow-path through the stages, e.g. series-parallel, e.g. side-loads
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D31/00—Pumping liquids and elastic fluids at the same time
Definitions
- the present invention relates to fluid processing systems for deployment in a subsea environment, and more particularly to subsea systems capable of handling production fluids characterized by high gas volume fraction (GVF).
- VVF gas volume fraction
- Fluid processing systems used for hydrocarbon production in subsea environments typically include pumps configured to boost production fluids from a subsea hydrocarbon reservoir to a distant storage facility. Such pumps are typically designed to operate with production fluids having relatively low gas volume fraction (GVF).
- VVF gas volume fraction
- gas slugs occur due to flow instability of multiple phases of the production fluids. Such flow instability may occur in pipelines deployed for moving the production fluids. Eventually, these gas slugs may enter the fluid processing systems and may cause rapid change in the GVF to higher values. Pumps receiving such production fluids with high GVF may be damaged thereby.
- a portion of a liquid phase of the production fluid may be re-circulated from a downstream separator to the inlet tank, where the liquid phase is mixed with the incoming production fluid before being fed to a pump.
- re-circulation of the liquid phase may result in overall pressure losses to the system as the liquid phase at high pressure needs to be throttled to lower pressure before being fed to the inlet tank.
- the liquid phase may tend to flash (i.e. convert from a liquid phase to a gaseous phase) which may reduce efficiency.
- the present invention provides a fluid processing system comprising: (a) a pump including a casing, one or more pump stages, a pump inlet, and a pump outlet, the casing defining one or more slots, wherein at least one of the slots is configured to extract at least a portion of a multiphase fluid flowing within the pump, and wherein each pump stage comprises a diffuser and an impeller; and (b) a fluid reservoir encompassing at least a portion of the casing and configured to receive and separate the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet, and a discharge device coupled to the re-circulation conduit and configured to regulate re-circulation of at least a portion of the extracted liquid phase to the pump via the pump inlet so as to reduce a gas volume fraction (GVF) of the multiphase fluid being fed to the pump.
- a gas volume fraction VVF
- the present invention provides a method for reducing a gas volume fraction of a production fluid comprising: (a) introducing a multiphase fluid into a pump configured to increase pressure of the multiphase fluid, wherein the pump comprises a casing, one or more pump stages, a pump inlet, and a pump outlet, wherein each pump stage comprises a diffuser and an impeller; (b) extracting at least a portion of the multiphase fluid flowing within the pump into a fluid reservoir encompassing at least a portion of the casing via one or more slots defined in the casing, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit; (c) separating the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase; (d) re-circulating at least a portion of the extracted liquid phase through the re-circulation conduit into the pump via the pump inlet by regulating a flow of the extracted liquid phase via the discharge device; and
- the present invention provides a method of transporting a production fluid comprising: (a) receiving a first production fluid in an inlet tank and mixing it with a primer liquid to produce thereby a second production fluid (multiphase fluid) having a reduced gas volume fraction (GVF) relative to the first production fluid; (b) introducing the multiphase fluid from the inlet tank into a pump configured to increase pressure of the multiphase fluid and produce thereby a compressed multiphase fluid, wherein the pump comprises a casing, one or more pump stages, a pump inlet, and a pump outlet, and wherein each pump stage comprises a diffuser and an impeller; (c) extracting at least a portion of the multiphase fluid flowing within the pump into a fluid reservoir encompassing at least a portion of the casing via one or more slots defined in the casing, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit; (d) separating the portion of the multiphase fluid
- FIG. 1 illustrates a subsea system in accordance to an embodiment of the invention
- FIG. 2 illustrates a fluid processing system in accordance to an embodiment of the invention
- FIG. 3 illustrates a fluid processing system in accordance to another embodiment of the invention
- FIG. 4 illustrates a pump and a fluid reservoir in accordance to an embodiment of the invention
- FIG. 5 illustrates a pump and a fluid reservoir in accordance to another embodiment of the invention
- FIG. 6 illustrates a portion of a pump in accordance to an embodiment of the invention
- FIG. 7 illustrates a portion of a pump in accordance to another embodiment of the invention.
- FIG. 8 illustrates a portion of a pump in accordance to yet another embodiment of the invention.
- FIG. 9 illustrates a portion of a pump in accordance to yet another embodiment of the invention.
- FIG. 10 illustrates a portion of a pump in accordance to yet another embodiment of the invention.
- FIG. 11 illustrates a portion of a pump in accordance to yet another embodiment of the invention.
- FIG. 12 illustrates a portion of a fluid processing system in accordance to an embodiment of the invention
- FIG. 13 illustrates a portion of a fluid processing system in accordance to another embodiment of the invention.
- FIG. 14 illustrates a portion of a subsea system in accordance to an embodiment of the invention
- FIG. 15 illustrates a portion of a fluid processing system in accordance to an embodiment of the invention.
- FIG. 16 illustrates a portion of a fluid processing system in accordance to another embodiment of the invention.
- Embodiments discussed herein disclose new subsea systems for efficiently moving production fluids characterized by high gas volume fraction (GVF) from a hydrocarbon reservoir to a distant fluid storage facility.
- the embodiments disclose an improved fluid processing system for effectively managing the GVF of the production fluids.
- the fluid processing system of the present invention comprises a pump and a fluid reservoir encompassing a portion of the pump.
- One or more slots defined in a casing of the pump are configured to extract a portion of a multiphase fluid flowing in the pump at an intermediate pressure.
- the one or more slots may be defined in one or more regions of the casing and may have optimal shapes to facilitate extraction of a stagnant portion (flow) of the multiphase fluid without affecting a main flow of the multiphase fluid.
- a discharge device is coupled to a re-circulation conduit of the fluid reservoir.
- the discharge device may include one among a passive device and an active device to efficiently regulate the quantity of and the pressure at which a liquid phase of the multiphase fluid being fed to the pump for controlling the GVF of the production fluids.
- Suitable discharge devices include valves and one or more cylinders comprising at least one hole or opening.
- FIG. 1 represents a subsea system 100 for handling production fluids deployed in a subsea environment 102 proximate to a hydrocarbon reservoir 104 .
- the hydrocarbon reservoir 104 may produce a production fluid comprising oil, water, and gas.
- the hydrocarbon reservoir 104 may produce a production fluid comprising a dry gas or crude oil and dry gas.
- the subsea system 100 includes an inlet tank 106 , a fluid processing system 108 , a fluid re-circulation loop 110 , and a fluid outlet 112 .
- the subsea system 100 further includes a fluid inlet 114 in fluid communication with the inlet tank 106 coupled to the hydrocarbon reservoir 104 , and a feed line 118 linking the fluid processing system 108 to the inlet tank 106 .
- the fluid inlet 114 may include a well-head valve (not shown in FIG. 1 ) for regulating a flow of a first production fluid stream 120 (i.e. production fluid) from the hydrocarbon reservoir 104 .
- the inlet tank 106 is configured to receive the production fluid stream 120 from the hydrocarbon reservoir 104 and a primer liquid stream 123 from a pump outlet 124 of the fluid processing system 108 via the fluid re-circulation loop 110 .
- the pump outlet 124 includes a liquid-gas separator (not shown in FIG. 1 ) configured to separate the primer liquid 123 from a compressed multiphase fluid 122 .
- the primer liquid stream 123 may be comprised of a liquid stream of the compressed multiphase fluid 122 .
- the inlet tank 106 is configured to mix the production fluid stream 120 and primer liquid stream 123 to produce thereby a second production fluid stream 126 (i.e. multiphase fluid) having a reduced gas volume fraction (GVF) relative to the production fluid 120 .
- VVF reduced gas volume fraction
- the primer liquid 123 may include one or more liquids separated from the multiphase production fluid 126 such as water and crude oil.
- the primer liquid 123 may comprise an exogenous liquid such as a solvent (e.g. ethanol) or other liquid not derived from the multiphase production fluid 126 .
- the fluid processing system 108 includes a pump 128 and a fluid reservoir 130 encompassing at least a portion of the pump 128 .
- the pump 128 has a pump inlet 132 , the pump outlet 124 , and one or more slots 134 defined in a casing 158 of the pump.
- the pump inlet 132 is fluidly coupled to the inlet tank 106 and the pump outlet 124 is fluidly coupled to both the inlet tank 106 and to a distant storage facility 138 .
- the fluid-recirculation loop 110 has a flow-control valve 136 configured to regulate a flow of the primer liquid stream 123 into the inlet tank 106 .
- the system 100 may include a plurality of pumps 128 coupled in a parallel configuration or in a serial configuration.
- the fluid reservoir 130 has a re-circulation conduit 140 disposed proximate to the pump inlet 132 , a re-injection conduit 142 disposed proximate to the one or more slots 134 , and a discharge device 144 coupled to the re-circulation conduit 140 .
- Pump 128 and fluid reservoir 130 are discussed in greater detail below.
- the system 100 further includes a pipe 116 disposed between the fluid inlet 114 and distant storage facility 138 .
- the pipe 116 has a by-pass valve 154 configured to regulate a flow of the production fluid stream 120 from the hydrocarbon reservoir 104 to the distant storage facility 138 based on one or more pre-determined conditions.
- the one or more pre-determined conditions may include start-up, shutdown, and maintenance of the subsea system 100 .
- inlet tank 106 receives and mixes the production fluid stream 120 from the hydrocarbon reservoir 104 with the primer liquid stream 123 from the pump outlet 124 to produce the multiphase fluid 126 having a reduced GVF relative to the production fluid 120 .
- the production fluid stream 120 may include gas slugs 156 which, as noted, may harm system components or affect efficiency.
- the multiphase fluid 126 is then fed to the fluid processing system 108 .
- the pump 128 receives the multiphase fluid stream 126 and increases its pressure. A portion of the multiphase fluid stream 126 flowing within the pump 128 at an intermediate pressure is extracted into the fluid reservoir 130 via the one or more slots 134 .
- the extracted portion of the multiphase fluid 126 settles down and phase separates into an extracted liquid phase 146 and extracted gaseous phase 148 .
- the fluid reservoir 130 itself is configured as a liquid-gas separator.
- the fluid reservoir 130 may include a discrete liquid-gas separator.
- the liquid-gas separator receives the extracted portion of the multiphase fluid 126 and separates the liquid phase from gaseous phase using, for example, a barrier, a filter, or a vortex flow separator.
- a suitable liquid-gas separator may include one or more weir separators, filter separators, cyclone separators, sheet metal separators, or a combination of two or more of the foregoing separators.
- a portion of the extracted liquid phase 146 is re-circulated as indicated by a reference numeral 150 , into the pump inlet 132 through the re-circulation conduit 140 .
- the re-circulation of the extracted liquid phase 146 into the pump inlet 132 is referred as an intermediate re-circulation.
- the discharge device 144 regulates the flow of the extracted liquid phase 146 into the pump inlet 132 where it is mixed with multiphase fluid 126 to further reduce the GVF of the multiphase fluid 126 being fed to the pump 128 .
- the extracted gaseous phase 148 is re-injected as indicated by reference numeral 152 , to the pump 128 through re-injection conduit 142 .
- the re-injection conduit 142 is shown as configured to deliver the gaseous phase 148 upstream of the one or more slots 134 .
- pump 128 produces the compressed multiphase fluid 122 , a portion of which may be separated for use as the primer liquid 123 .
- the subsea system 100 may include a plurality of sensors (not shown in FIG. 1 ) coupled to an electronic control unit (not shown in FIG. 1 ) for regulating the flow of the primer liquid stream 123 and/or the extracted liquid phase 146 and/or the production fluid stream 120 .
- the plurality of sensors may include one or more liquid-level indicators, flow meters, and speed sensors.
- the electronic control unit typically includes at least one data processor.
- the plurality of sensors may be configured to generate a plurality of input signals based on a plurality of sensed parameters of the subsea system 100 .
- the electronic control unit may be configured to generate one or more control signals based on the plurality of input signals.
- the electronic control unit generates a control signal to regulate feeding of the primer liquid stream 123 to the inlet tank 106 via the flow control valve 136 .
- the control unit may generate a control signal to regulate intermediate re-circulation of the portion of extracted liquid phase 146 into the pump inlet 132 via the discharge device 144 .
- the electronic control unit may be configured to regulate feeding of the production fluid stream 120 to the distant storage facility 138 via the by-pass valve 154 .
- FIG. 2 represents a fluid processing system 108 in accordance with an exemplary embodiment.
- the fluid processing system 108 includes a pump 128 and a fluid reservoir 130 .
- the fluid reservoir 130 is an integral component of the pump 128 .
- the fluid reservoir 130 may be a discrete component which may be fluidly coupled to the pump 128 via pipes.
- Pump 128 has a shaft 160 disposed at least partially within a casing 158 and coupled to a motor (not shown in FIG. 2 ), and one or more pump stages 162 .
- Each pump stage 162 has an impeller 164 and a diffuser 166 .
- the pump 128 has one or more slots 134 such as through-holes, defined in the casing 158 .
- the one or more slots 134 are located proximate to a pump inlet 132 . In the embodiment shown, the one or more slots 134 are located after a second pump stage 162 b from the pump inlet 132 .
- Each slot 134 is positioned at about 20 percent to about 80 percent of a length “L” of the diffuser 166 .
- suitable pumps include rotary pumps, centrifugal pumps, and reciprocating pumps.
- the re-injection conduit 142 is disposed between a first opening 174 formed in a top portion 170 of the fluid reservoir 130 and a second opening 176 formed in the casing 158 .
- the re-circulation conduit 140 has an opening 178 disposed proximate to the pump inlet 132 .
- the opening 178 is located at a bottom portion 172 of the fluid reservoir 130 .
- the re-circulation conduit 140 further includes the discharge device 144 disposed at the opening 178 .
- the one or more slots 134 and the discharge device 144 are discussed in greater detail below.
- multiphase fluid 126 is compressed at each pump stage 162 via the impeller 164 and guided to a subsequent pump stage 162 via the diffuser 166 .
- the one or more slots 134 extract a portion of the multiphase fluid 126 at an intermediate pressure from the pump 128 .
- the extraction of the multiphase fluid 126 is indicated by a reference numeral 180 .
- the extracted multiphase fluid 126 is separated into liquid phase and gaseous phase. As dictated by gravity, the extracted liquid phase 146 is stored at the bottom portion 172 of the fluid reservoir 130 and the extracted gaseous phase 148 is stored at the top portion 170 of the fluid reservoir 130 .
- the extracted gaseous phase 148 is re-injected to the pump 128 through the re-injection conduit 142 wherein a portion of the extracted liquid phase 146 is re-circulated to the pump 128 through the re-circulation conduit 140 .
- the discharge device 144 regulates the flow of the extracted liquid phase 146 .
- the re-circulation may depend on the GVF at the pump inlet 132 .
- FIG. 3 represents a fluid processing system 108 in accordance with another exemplary embodiment.
- the illustrated embodiment does not include a separate re-injection conduit 142 as shown in the embodiment of FIG. 2 .
- One or more slots 134 defined in the casing 158 is configured for both extraction (as indicated by reference numeral 180 ) of the multiphase fluid 126 from the pump 128 and re-injection (as indicated by reference numeral 152 ) of the extracted gaseous phase 148 into the pump 128 .
- the extraction and re-injection may happen at the same pump stage 162 .
- FIG. 4 represents a fluid processing system 108 comprising a pump 128 and a fluid reservoir 130 in accordance with an exemplary embodiment.
- the pump 128 includes a first pump inlet 182 and a first pump outlet 184 .
- the pump 128 has a first set of pump stages 162 a and a second set of pump stages 162 b disposed within a casing 158 .
- the first set of pump stages 162 a is disposed between a pump inlet 132 and the first pump outlet 184 .
- the second set of pump stages 162 b is disposed between the first pump inlet 182 and a pump outlet 124 .
- the first pump inlet 184 and first pump outlet 182 are fluidly coupled to each other via a conduit 186 .
- the first and second set of pump stages 162 a and 162 b are in a serial configuration.
- the casing 158 further includes one or more slots 134 disposed upstream relative to the first pump outlet 184 .
- the fluid reservoir 130 encompasses the portion of the casing 158 defining the first set of pump stages 162 a.
- multiphase fluid 126 enters the first set of pump stages 162 a where it is compressed to a first pressure.
- a portion of the multiphase fluid 126 at the first pressure is extracted through the one or more slots 134 into the fluid reservoir 130 , as discussed earlier.
- the first pressure may be an intermediate pressure.
- a remaining portion of the multiphase fluid 126 substantially above the first pressure exits the first set of pump stages 162 a through the first pump outlet 184 and flows in the conduit 186 before being fed to the second set of pump stages 162 b via the first pump inlet 182 .
- the multiphase fluid 126 is then compressed along the second set of pump stages 162 b to generate the compressed multiphase fluid 122 at a second pressure.
- the pump outlet 124 discharges the compressed multiphase fluid 122 from the pump 128 .
- FIG. 5 represents a fluid processing system 108 comprising a pump 128 and a fluid reservoir 130 in accordance with an exemplary embodiment.
- the pump 128 includes a first pump inlet 132 a disposed at a first end 188 of the pump 128 and a second pump inlet 132 b disposed at a second end 190 opposite to the first end 188 , of the pump 128 .
- the pump 128 has a first set of pump stages 162 a and a second set of pump stages 162 b disposed within a casing 158 .
- the first and second set of pump stages 162 a and 162 b are in a parallel configuration.
- the pump outlet 124 is disposed at an exit section of the first and second set of pump stages 162 a and 162 b .
- the fluid reservoir 130 encompasses the portion of the casing 158 defining the first set of pump stages 162 a .
- the bottom portion 172 of the fluid reservoir 130 further includes a liquid conduit 192 fluidly coupled to the second fluid inlet 132 b .
- the liquid conduit 192 includes a control valve 194 .
- the top portion 170 of the fluid reservoir 130 includes a gaseous conduit 196 fluidly coupled to a portion of the casing 158 corresponding to the second set of pump stages 162 b.
- multiphase fluid 126 enters the first and second set of pump stages 162 a and 162 b of the pump 128 .
- the multiphase fluid 126 is compressed along the one or more stages of the first and second set of pump stages 162 a and 162 b .
- a portion of the multiphase fluid 126 flowing along the first set of pump stages 162 a is extracted into the fluid reservoir 130 through one or more slots 134 as discussed earlier.
- a remaining portion of the multiphase fluid 126 flowing along the first set of pump stages 162 a and the multiphase fluid 126 flowing along the second set of pump stages 162 b are compressed to generate the compressed multiphase fluid 122 .
- the pump outlet 124 discharges the compressed multiphase fluid 122 from the pump 128 .
- a portion of the extracted liquid phase 146 is fed from the fluid reservoir 130 into the second pump inlet 132 b via the liquid conduit 192 .
- the control valve 194 may regulate a flow of the portion of the extracted liquid phase 146 .
- a portion of the extracted gaseous phase 148 may be fed from the fluid reservoir 130 into the second set of pump stages 162 b via the gaseous conduit 196 .
- FIG. 6 represents a portion 197 of a pump 128 in accordance with an exemplary embodiment.
- the portion 197 has a plurality of diffusers 166 and a slot 134 defined in a casing 158 .
- the slot 134 is positioned corresponding to a mid-length of the plurality of diffusers 166 and has a width “W 1 ”. Further, the slot 134 is a continuous slot having a uniform size along the casing 158 . In certain other embodiments, the slot 134 may be positioned anywhere between a leading edge 204 and a trailing edge 206 of the plurality of diffusers 166 .
- the slot 134 may be positioned at about 20 percent to about 80 percent of the length “L” of the plurality of diffusers 166 .
- the slot 134 may be configured to extract a portion of the multiphase fluid 126 from the pump 128 and to re-inject an extracted gaseous phase 148 into the pump 128 .
- FIG. 7 represents a portion 199 of a pump 128 in accordance with another exemplary embodiment.
- a slot 134 defined in a casing 158 has a width “W 2 ” different than the width “W 1 ” as shown in the embodiment of FIG. 6 .
- the slot 134 having a smaller width may accurately regulate a quantity of a multiphase fluid 126 extracted into the fluid reservoir 130 .
- the slot 134 is a continuous slot having a uniform size along the casing 158 and is positioned at a mid-length of a plurality of diffusers 166 .
- FIG. 8 represents a portion 201 of a pump 128 in accordance with yet another exemplary embodiment.
- a slot 134 is located proximate to a leading edge 204 of a plurality of diffusers 166 . Similar to the embodiment of FIG. 6 , the slot 134 is a continuous slot having a uniform size along a casing 158 .
- FIG. 9 represents a portion 203 of a pump 128 in accordance with yet another exemplary embodiment.
- a slot 134 is located proximate to a trailing edge 206 of a plurality of diffusers 166 . Similar to the embodiment of FIG. 6 , the slot 134 is a continuous slot having a uniform size along a casing 158 .
- FIG. 10 represents a portion of 205 of a pump 128 in accordance with yet another exemplary embodiment.
- the portion 205 has one or more discrete slots 134 defined in a casing 158 .
- each slot 134 is positioned corresponding to a mid-length of a plurality of diffusers 166 .
- each slot 134 has a width “W 1 ” and covers a portion of a pressure side 202 and a suction side 200 of at least one diffuser 166 .
- each slot 134 may have different width and may be positioned anywhere between a leading edge 204 and a trailing edge 206 of the plurality of diffusers 166 .
- FIG. 11 represents a portion of 207 of a pump 128 in accordance with yet another exemplary embodiment.
- the portion 207 includes one or more discrete slots 134 defined in a casing 158 .
- each slot 134 is positioned proximate to a trailing edge 206 .
- Each slot 134 has a non-uniform size along the casing 158 and is disposed between a suction side 200 of a diffuser 166 and a pressure side 202 of a mutually adjacent diffuser 166 .
- each slot 134 may be chosen such that an extraction of the multiphase fluid 126 happens from an area of the diffuser 166 where the multiphase fluid 126 tends to re-circulate (or have more turbulence or is a stagnant flow) within the pump 128 .
- Each slot 134 removes the stagnant flow (i.e. low quality flow) from such area of the diffuser 166 to improvise an aero dynamic effect of the multiphase fluid 126 within the pump 128 .
- FIG. 12 represents a portion 208 of a fluid processing system 108 in accordance with an exemplary embodiment.
- the portion 208 illustrates a discharge device 144 in accordance to the exemplary embodiment.
- the discharge device 144 is an active device including a plurality of concentric cylinders 210 disposed at an opening 178 of the re-circulation conduit 140 .
- An outer concentric cylinder 210 a among the plurality of concentric cylinders 210 has a side wall 212 rotatably engaged with an outer wall 214 of the re-circulation conduit 140 .
- an inner concentric cylinder 210 b among the plurality of concentric cylinders 210 has a side wall 216 coupled to a casing 158 of a pump 128 .
- the side walls 212 and 216 are inclined at a pre-determined angle “a” relative to a wall 219 of a pump inlet 132 .
- the pre-determined angle “a” may be a negative angle, a positive angle, zero, or combination thereof depending on an application and design criteria.
- the plurality of concentric cylinders 210 is a hollow cylinder with each cylinder 210 having one or more holes 218 spaced apart from each other and disposed along a circumference of each cylinder 210 .
- the outer concentric cylinder 210 a is coupled to an actuator (not shown in FIG. 12 ) for rotating (as designated by a reference number 217 ) the cylinder 210 a about an axis of the shaft 160 .
- the inner concentric cylinder 210 b is a stationary cylinder. In certain other embodiments, the outer concentric cylinder 210 a may be stationary and the inner concentric cylinder 210 b may be rotatable about the axis of the shaft 160 .
- actuator may rotate the outer concentric cylinder 210 a for aligning one or more holes 218 a with one or more holes 218 b of inner concentric cylinder 210 b .
- Such alignment of holes 218 a and 218 b allows the extracted liquid phase 146 to flow through the discharge device 144 into the pump inlet 132 .
- the outer concentric cylinder 210 a may be regulated via the actuator by an electronic control unit as discussed in the embodiment of FIG. 1 .
- the concentric cylinders 210 may control a pressure and a quantity of the extracted liquid phase 146 being re-circulated into the pump 128 .
- suitable actuators may include motors.
- FIG. 13 represents a portion 209 of a fluid processing system 108 in accordance with another exemplary embodiment.
- the portion 209 illustrates a discharge device 144 in accordance to the exemplary embodiment.
- the discharge device 144 is an active device including a valve 220 disposed in a pipe 222 which is coupled between a re-circulation conduit 140 and a pump inlet 132 .
- the valve 220 may be driven by an actuator to regulate intermediate re-circulation of an extracted liquid phase 146 into the pump inlet 132 .
- FIG. 14 represents a portion 211 of a subsea system 100 in accordance to an exemplary embodiment.
- the portion 211 illustrates a discharge device 144 and an actuator 225 .
- the discharge device 144 is a passive device including a valve 224 disposed in a pipe 222 coupled to a re-circulation conduit 140 and a pump inlet 132 .
- the actuator 225 is disposed in a conduit 232 coupled to a fluid outlet 112 and the pipe 222 via an opening 230 .
- the actuator 225 is further coupled to the valve 224 .
- the actuator 225 is a first piston including a spring 234 disposed between a piston head (not labeled) and the opening 230 .
- a portion of a compressed multiphase fluid 122 flows in the conduit 232 and a portion of an extracted liquid phase 146 flows in the pipe 222 .
- the first piston 225 is configured to reciprocate along the opening 230 to either engage or disengage the valve 224 based on a pressure difference between the pipe 222 and conduit 232 . For example, when a pressure applied by the compressed multiphase fluid 122 in the conduit 232 is significantly greater than a pressure applied by the extracted liquid phase 146 in the pipe 222 , the first piston 225 engages the valve 224 and obstructs a flow of the extracted liquid phase 146 into the pump inlet 132 .
- the first piston 225 disengages the valve 224 and allows the flow of the liquid phase 146 into the pump inlet 132 .
- the conduit 232 may further include a second piston (not shown in FIG. 14 ) disposed at an opening 113 formed in the fluid outlet 112 .
- the conduit 232 may be filled with a fluid such as oil and water, different than the compressed fluid 112 .
- the second piston may compress the fluid based on the pressure of the compressed multiphase fluid 122 flowing in the fluid outlet 112 and thereby increase the pressure across the first piston 225 to engage the valve 224 .
- FIG. 15 represents a portion 213 of a fluid processing system 108 in accordance with yet another exemplary embodiment.
- the portion 213 illustrates a discharge device 144 in accordance to the exemplary embodiment.
- the discharge device 144 is a passive device including a cylinder 236 disposed at an opening 178 of a re-circulation conduit 140 .
- the cylinder 236 includes a side wall 240 coupled to a casing 158 and an outer wall 214 of a fluid reservoir 130 .
- the side wall 240 is inclined at a pre-determined angle “a” relative to a wall 219 of a pump inlet 132 .
- the cylinder 236 is a hollow cylinder with one or more holes 238 spaced apart from each other and disposed along a circumference of the cylinder 236 .
- the cylinder 236 is a stationary cylinder.
- an extracted liquid phase 146 is re-circulated continuously from the re-circulation conduit 140 into the pump inlet 132 via the one or more holes
- the side wall 240 is inclined at a zero angle relative to the wall 219 i.e. the side wall 240 is disposed substantially parallel to the wall 219 .
- the cylinder 236 may move up and/or down via an actuator, to either open and/or close a portion of the holes 238 for selectively allowing the extracted liquid phase 146 to flow into the pump inlet 132 .
- FIG. 16 represents a portion 215 of a fluid processing system 108 in accordance with yet another exemplary embodiment.
- the portion 215 illustrates a discharge device 144 in accordance to the exemplary embodiment.
- the discharge device 144 is a passive device including a cylinder 242 disposed at an opening 178 of a fluid reservoir 130 .
- the cylinder 242 includes a hole 244 such as a slit, defined along a circumference of the cylinder 242 .
- the hole 244 is substantially perpendicular relative to a wall 219 of a pump inlet 132 .
- an extracted liquid phase 146 is re-circulated from a re-circulation conduit 140 into the pump inlet 132 via the hole 244 .
- the cylinder 242 may move up and/or down via an actuator, to either open and/or close a portion of the slit 244 for selectively allowing the liquid phase 146 to flow into the pump inlet 132 .
- a subsea system facilitates an efficient way of transporting a production fluid characterized by high gas volume fraction (gas slugs) from a subsea hydrocarbon reservoir to a distant storage facility.
- the subsea system mixes a primer liquid with the production fluid primarily within an inlet tank to reduce a gas volume fraction (GVF) of the production fluid entering a pump and causing damage to the pump.
- VVF gas volume fraction
- a fluid processing system of the present invention allows extraction of a portion of the multiphase fluid at an intermediate pressure from the pump, separation of a gaseous phase from a liquid phase, and intermediate re-circulation of the extracted liquid phase into the pump to further reduce the GVF of the multiphase fluid at the pump inlet thereby avoiding the further damage to the pump.
- the process of re-circulation of the primer liquid and the intermediate re-circulation of the extracted liquid phase may be automated by having a plurality of sensors and an electronic control unit.
Abstract
A fluid processing system is provided containing a pump and a fluid reservoir. The pump includes a casing, one or more pump stages, a pump inlet, and a pump outlet. The casing includes one or more slots, with at least one slot configured to extract at least a portion of a multiphase fluid flowing within the pump. The fluid reservoir encompasses at least a portion of the casing and is configured to receive and separate the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase. The fluid reservoir includes a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit. The discharge device regulates re-circulation of at least a portion of the extracted liquid phase to the pump via the pump inlet for reducing a gas volume fraction of the multiphase fluid being fed to the pump.
Description
- This application claims priority under 35 U.S.C. §119(e) from Provisional Application No. 62/079,125 filed on 13 Nov. 2014, which is incorporated by reference herein in its entirety.
- The present invention relates to fluid processing systems for deployment in a subsea environment, and more particularly to subsea systems capable of handling production fluids characterized by high gas volume fraction (GVF).
- Fluid processing systems used for hydrocarbon production in subsea environments typically include pumps configured to boost production fluids from a subsea hydrocarbon reservoir to a distant storage facility. Such pumps are typically designed to operate with production fluids having relatively low gas volume fraction (GVF).
- Generally, gas slugs occur due to flow instability of multiple phases of the production fluids. Such flow instability may occur in pipelines deployed for moving the production fluids. Eventually, these gas slugs may enter the fluid processing systems and may cause rapid change in the GVF to higher values. Pumps receiving such production fluids with high GVF may be damaged thereby.
- To protect the pumps from incoming gas slugs, a portion of a liquid phase of the production fluid may be re-circulated from a downstream separator to the inlet tank, where the liquid phase is mixed with the incoming production fluid before being fed to a pump. However, such re-circulation of the liquid phase may result in overall pressure losses to the system as the liquid phase at high pressure needs to be throttled to lower pressure before being fed to the inlet tank. Further, when the pressure is lowered the liquid phase may tend to flash (i.e. convert from a liquid phase to a gaseous phase) which may reduce efficiency.
- Thus, there is a need for an improved fluid processing system for efficiently handling production fluids characterized by high gas volume fraction (GVF) and to regulate the GVF of a production fluid being fed to a processing system pump.
- In one embodiment, the present invention provides a fluid processing system comprising: (a) a pump including a casing, one or more pump stages, a pump inlet, and a pump outlet, the casing defining one or more slots, wherein at least one of the slots is configured to extract at least a portion of a multiphase fluid flowing within the pump, and wherein each pump stage comprises a diffuser and an impeller; and (b) a fluid reservoir encompassing at least a portion of the casing and configured to receive and separate the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet, and a discharge device coupled to the re-circulation conduit and configured to regulate re-circulation of at least a portion of the extracted liquid phase to the pump via the pump inlet so as to reduce a gas volume fraction (GVF) of the multiphase fluid being fed to the pump.
- In another embodiment, the present invention provides a method for reducing a gas volume fraction of a production fluid comprising: (a) introducing a multiphase fluid into a pump configured to increase pressure of the multiphase fluid, wherein the pump comprises a casing, one or more pump stages, a pump inlet, and a pump outlet, wherein each pump stage comprises a diffuser and an impeller; (b) extracting at least a portion of the multiphase fluid flowing within the pump into a fluid reservoir encompassing at least a portion of the casing via one or more slots defined in the casing, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit; (c) separating the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase; (d) re-circulating at least a portion of the extracted liquid phase through the re-circulation conduit into the pump via the pump inlet by regulating a flow of the extracted liquid phase via the discharge device; and (e) mixing the extracted liquid phase with the multiphase fluid at the pump inlet so as to reduce the gas volume fraction (GVF) of the multiphase fluid being fed to the pump.
- In another embodiment, the present invention provides a method of transporting a production fluid comprising: (a) receiving a first production fluid in an inlet tank and mixing it with a primer liquid to produce thereby a second production fluid (multiphase fluid) having a reduced gas volume fraction (GVF) relative to the first production fluid; (b) introducing the multiphase fluid from the inlet tank into a pump configured to increase pressure of the multiphase fluid and produce thereby a compressed multiphase fluid, wherein the pump comprises a casing, one or more pump stages, a pump inlet, and a pump outlet, and wherein each pump stage comprises a diffuser and an impeller; (c) extracting at least a portion of the multiphase fluid flowing within the pump into a fluid reservoir encompassing at least a portion of the casing via one or more slots defined in the casing, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit; (d) separating the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase; (e) re-circulating at least a portion of the extracted liquid phase through the re-circulation conduit into the pump via the pump inlet by regulating a flow of the extracted liquid phase via the discharge device; (f) mixing the extracted liquid phase with the multiphase fluid at the pump inlet to further reduce the GVF of the multiphase fluid being fed to the pump; and (g) transporting the compressed multiphase fluid from the pump to a fluid storage facility via a fluid conduit.
- These and other features and aspects of embodiments of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
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FIG. 1 illustrates a subsea system in accordance to an embodiment of the invention; -
FIG. 2 illustrates a fluid processing system in accordance to an embodiment of the invention; -
FIG. 3 illustrates a fluid processing system in accordance to another embodiment of the invention; -
FIG. 4 illustrates a pump and a fluid reservoir in accordance to an embodiment of the invention; -
FIG. 5 illustrates a pump and a fluid reservoir in accordance to another embodiment of the invention; -
FIG. 6 illustrates a portion of a pump in accordance to an embodiment of the invention; -
FIG. 7 illustrates a portion of a pump in accordance to another embodiment of the invention; -
FIG. 8 illustrates a portion of a pump in accordance to yet another embodiment of the invention; -
FIG. 9 illustrates a portion of a pump in accordance to yet another embodiment of the invention; -
FIG. 10 illustrates a portion of a pump in accordance to yet another embodiment of the invention; -
FIG. 11 illustrates a portion of a pump in accordance to yet another embodiment of the invention; -
FIG. 12 illustrates a portion of a fluid processing system in accordance to an embodiment of the invention; -
FIG. 13 illustrates a portion of a fluid processing system in accordance to another embodiment of the invention; -
FIG. 14 illustrates a portion of a subsea system in accordance to an embodiment of the invention; -
FIG. 15 illustrates a portion of a fluid processing system in accordance to an embodiment of the invention; and -
FIG. 16 illustrates a portion of a fluid processing system in accordance to another embodiment of the invention. - Embodiments discussed herein disclose new subsea systems for efficiently moving production fluids characterized by high gas volume fraction (GVF) from a hydrocarbon reservoir to a distant fluid storage facility. Specifically, the embodiments disclose an improved fluid processing system for effectively managing the GVF of the production fluids. The fluid processing system of the present invention comprises a pump and a fluid reservoir encompassing a portion of the pump. One or more slots defined in a casing of the pump, are configured to extract a portion of a multiphase fluid flowing in the pump at an intermediate pressure. The one or more slots may be defined in one or more regions of the casing and may have optimal shapes to facilitate extraction of a stagnant portion (flow) of the multiphase fluid without affecting a main flow of the multiphase fluid. A discharge device is coupled to a re-circulation conduit of the fluid reservoir. The discharge device may include one among a passive device and an active device to efficiently regulate the quantity of and the pressure at which a liquid phase of the multiphase fluid being fed to the pump for controlling the GVF of the production fluids. Suitable discharge devices include valves and one or more cylinders comprising at least one hole or opening.
-
FIG. 1 represents asubsea system 100 for handling production fluids deployed in asubsea environment 102 proximate to ahydrocarbon reservoir 104. Thehydrocarbon reservoir 104 may produce a production fluid comprising oil, water, and gas. In certain embodiments, thehydrocarbon reservoir 104 may produce a production fluid comprising a dry gas or crude oil and dry gas. - The
subsea system 100 includes aninlet tank 106, afluid processing system 108, afluid re-circulation loop 110, and afluid outlet 112. Thesubsea system 100 further includes afluid inlet 114 in fluid communication with theinlet tank 106 coupled to thehydrocarbon reservoir 104, and afeed line 118 linking thefluid processing system 108 to theinlet tank 106. In certain other embodiments, thefluid inlet 114 may include a well-head valve (not shown inFIG. 1 ) for regulating a flow of a first production fluid stream 120 (i.e. production fluid) from thehydrocarbon reservoir 104. Theinlet tank 106 is configured to receive theproduction fluid stream 120 from thehydrocarbon reservoir 104 and a primerliquid stream 123 from apump outlet 124 of thefluid processing system 108 via thefluid re-circulation loop 110. In one or more embodiments, thepump outlet 124 includes a liquid-gas separator (not shown inFIG. 1 ) configured to separate theprimer liquid 123 from acompressed multiphase fluid 122. The primerliquid stream 123 may be comprised of a liquid stream of thecompressed multiphase fluid 122. Theinlet tank 106 is configured to mix theproduction fluid stream 120 and primerliquid stream 123 to produce thereby a second production fluid stream 126 (i.e. multiphase fluid) having a reduced gas volume fraction (GVF) relative to theproduction fluid 120. In one or more embodiments, theprimer liquid 123 may include one or more liquids separated from themultiphase production fluid 126 such as water and crude oil. In alternative embodiment, theprimer liquid 123 may comprise an exogenous liquid such as a solvent (e.g. ethanol) or other liquid not derived from themultiphase production fluid 126. - The
fluid processing system 108 includes apump 128 and afluid reservoir 130 encompassing at least a portion of thepump 128. Thepump 128 has apump inlet 132, thepump outlet 124, and one ormore slots 134 defined in acasing 158 of the pump. Thepump inlet 132 is fluidly coupled to theinlet tank 106 and thepump outlet 124 is fluidly coupled to both theinlet tank 106 and to adistant storage facility 138. In the embodiment shown, the fluid-recirculation loop 110 has a flow-control valve 136 configured to regulate a flow of the primerliquid stream 123 into theinlet tank 106. In certain other embodiments, thesystem 100 may include a plurality ofpumps 128 coupled in a parallel configuration or in a serial configuration. Thefluid reservoir 130 has are-circulation conduit 140 disposed proximate to thepump inlet 132, are-injection conduit 142 disposed proximate to the one ormore slots 134, and adischarge device 144 coupled to there-circulation conduit 140.Pump 128 andfluid reservoir 130 are discussed in greater detail below. - The
system 100 further includes apipe 116 disposed between thefluid inlet 114 anddistant storage facility 138. Thepipe 116 has a by-pass valve 154 configured to regulate a flow of theproduction fluid stream 120 from thehydrocarbon reservoir 104 to thedistant storage facility 138 based on one or more pre-determined conditions. In one or more embodiments, the one or more pre-determined conditions may include start-up, shutdown, and maintenance of thesubsea system 100. - During
operation inlet tank 106 receives and mixes theproduction fluid stream 120 from thehydrocarbon reservoir 104 with theprimer liquid stream 123 from thepump outlet 124 to produce themultiphase fluid 126 having a reduced GVF relative to theproduction fluid 120. Theproduction fluid stream 120 may includegas slugs 156 which, as noted, may harm system components or affect efficiency. Themultiphase fluid 126 is then fed to thefluid processing system 108. - The
pump 128 receives themultiphase fluid stream 126 and increases its pressure. A portion of themultiphase fluid stream 126 flowing within thepump 128 at an intermediate pressure is extracted into thefluid reservoir 130 via the one ormore slots 134. - In the
fluid reservoir 130 the extracted portion of themultiphase fluid 126 settles down and phase separates into an extractedliquid phase 146 and extractedgaseous phase 148. In one or more embodiments, thefluid reservoir 130 itself is configured as a liquid-gas separator. In other embodiments, thefluid reservoir 130 may include a discrete liquid-gas separator. In such embodiments, the liquid-gas separator receives the extracted portion of themultiphase fluid 126 and separates the liquid phase from gaseous phase using, for example, a barrier, a filter, or a vortex flow separator. In one or more embodiments, a suitable liquid-gas separator may include one or more weir separators, filter separators, cyclone separators, sheet metal separators, or a combination of two or more of the foregoing separators. - A portion of the extracted
liquid phase 146 is re-circulated as indicated by areference numeral 150, into thepump inlet 132 through there-circulation conduit 140. In one or more embodiments, the re-circulation of the extractedliquid phase 146 into thepump inlet 132 is referred as an intermediate re-circulation. Thedischarge device 144 regulates the flow of the extractedliquid phase 146 into thepump inlet 132 where it is mixed withmultiphase fluid 126 to further reduce the GVF of themultiphase fluid 126 being fed to thepump 128. The extractedgaseous phase 148 is re-injected as indicated byreference numeral 152, to thepump 128 throughre-injection conduit 142. There-injection conduit 142 is shown as configured to deliver thegaseous phase 148 upstream of the one ormore slots 134. As notedpump 128 produces the compressedmultiphase fluid 122, a portion of which may be separated for use as theprimer liquid 123. - In one or more embodiments, the
subsea system 100 may include a plurality of sensors (not shown inFIG. 1 ) coupled to an electronic control unit (not shown inFIG. 1 ) for regulating the flow of theprimer liquid stream 123 and/or the extractedliquid phase 146 and/or theproduction fluid stream 120. The plurality of sensors may include one or more liquid-level indicators, flow meters, and speed sensors. The electronic control unit typically includes at least one data processor. The plurality of sensors may be configured to generate a plurality of input signals based on a plurality of sensed parameters of thesubsea system 100. The electronic control unit may be configured to generate one or more control signals based on the plurality of input signals. - In one embodiment, the electronic control unit generates a control signal to regulate feeding of the
primer liquid stream 123 to theinlet tank 106 via theflow control valve 136. The control unit may generate a control signal to regulate intermediate re-circulation of the portion of extractedliquid phase 146 into thepump inlet 132 via thedischarge device 144. The electronic control unit may be configured to regulate feeding of theproduction fluid stream 120 to thedistant storage facility 138 via the by-pass valve 154. -
FIG. 2 represents afluid processing system 108 in accordance with an exemplary embodiment. Thefluid processing system 108 includes apump 128 and afluid reservoir 130. In the embodiments shown, thefluid reservoir 130 is an integral component of thepump 128. In certain other embodiments, thefluid reservoir 130 may be a discrete component which may be fluidly coupled to thepump 128 via pipes. -
Pump 128 has ashaft 160 disposed at least partially within acasing 158 and coupled to a motor (not shown inFIG. 2 ), and one or more pump stages 162. Eachpump stage 162 has animpeller 164 and adiffuser 166. Thepump 128 has one ormore slots 134 such as through-holes, defined in thecasing 158. The one ormore slots 134 are located proximate to apump inlet 132. In the embodiment shown, the one ormore slots 134 are located after asecond pump stage 162 b from thepump inlet 132. Eachslot 134 is positioned at about 20 percent to about 80 percent of a length “L” of thediffuser 166. In one or more embodiments, suitable pumps include rotary pumps, centrifugal pumps, and reciprocating pumps. - The
re-injection conduit 142 is disposed between afirst opening 174 formed in atop portion 170 of thefluid reservoir 130 and asecond opening 176 formed in thecasing 158. There-circulation conduit 140 has anopening 178 disposed proximate to thepump inlet 132. Theopening 178 is located at abottom portion 172 of thefluid reservoir 130. There-circulation conduit 140 further includes thedischarge device 144 disposed at theopening 178. The one ormore slots 134 and thedischarge device 144 are discussed in greater detail below. - During operation
multiphase fluid 126 is compressed at eachpump stage 162 via theimpeller 164 and guided to asubsequent pump stage 162 via thediffuser 166. The one ormore slots 134 extract a portion of themultiphase fluid 126 at an intermediate pressure from thepump 128. In the illustrated embodiment, the extraction of themultiphase fluid 126 is indicated by areference numeral 180. The extractedmultiphase fluid 126 is separated into liquid phase and gaseous phase. As dictated by gravity, the extractedliquid phase 146 is stored at thebottom portion 172 of thefluid reservoir 130 and the extractedgaseous phase 148 is stored at thetop portion 170 of thefluid reservoir 130. The extractedgaseous phase 148 is re-injected to thepump 128 through there-injection conduit 142 wherein a portion of the extractedliquid phase 146 is re-circulated to thepump 128 through there-circulation conduit 140. Thedischarge device 144 regulates the flow of the extractedliquid phase 146. In one or more embodiments, the re-circulation may depend on the GVF at thepump inlet 132. -
FIG. 3 represents afluid processing system 108 in accordance with another exemplary embodiment. The illustrated embodiment does not include aseparate re-injection conduit 142 as shown in the embodiment ofFIG. 2 . One ormore slots 134 defined in thecasing 158 is configured for both extraction (as indicated by reference numeral 180) of themultiphase fluid 126 from thepump 128 and re-injection (as indicated by reference numeral 152) of the extractedgaseous phase 148 into thepump 128. The extraction and re-injection may happen at thesame pump stage 162. -
FIG. 4 represents afluid processing system 108 comprising apump 128 and afluid reservoir 130 in accordance with an exemplary embodiment. Thepump 128 includes afirst pump inlet 182 and afirst pump outlet 184. Thepump 128 has a first set of pump stages 162 a and a second set of pump stages 162 b disposed within acasing 158. The first set of pump stages 162 a is disposed between apump inlet 132 and thefirst pump outlet 184. The second set of pump stages 162 b is disposed between thefirst pump inlet 182 and apump outlet 124. Thefirst pump inlet 184 andfirst pump outlet 182 are fluidly coupled to each other via aconduit 186. The first and second set of pump stages 162 a and 162 b are in a serial configuration. Thecasing 158 further includes one ormore slots 134 disposed upstream relative to thefirst pump outlet 184. Thefluid reservoir 130 encompasses the portion of thecasing 158 defining the first set of pump stages 162 a. - During operation
multiphase fluid 126 enters the first set of pump stages 162 a where it is compressed to a first pressure. A portion of themultiphase fluid 126 at the first pressure is extracted through the one ormore slots 134 into thefluid reservoir 130, as discussed earlier. In one or more embodiments, the first pressure may be an intermediate pressure. A remaining portion of themultiphase fluid 126 substantially above the first pressure exits the first set of pump stages 162 a through thefirst pump outlet 184 and flows in theconduit 186 before being fed to the second set of pump stages 162 b via thefirst pump inlet 182. Themultiphase fluid 126 is then compressed along the second set of pump stages 162 b to generate the compressedmultiphase fluid 122 at a second pressure. Thepump outlet 124 discharges the compressedmultiphase fluid 122 from thepump 128. -
FIG. 5 represents afluid processing system 108 comprising apump 128 and afluid reservoir 130 in accordance with an exemplary embodiment. Thepump 128 includes afirst pump inlet 132 a disposed at afirst end 188 of thepump 128 and asecond pump inlet 132 b disposed at asecond end 190 opposite to thefirst end 188, of thepump 128. Thepump 128 has a first set of pump stages 162 a and a second set of pump stages 162 b disposed within acasing 158. The first and second set of pump stages 162 a and 162 b are in a parallel configuration. Thepump outlet 124 is disposed at an exit section of the first and second set of pump stages 162 a and 162 b. Thefluid reservoir 130 encompasses the portion of thecasing 158 defining the first set of pump stages 162 a. Thebottom portion 172 of thefluid reservoir 130 further includes aliquid conduit 192 fluidly coupled to the secondfluid inlet 132 b. Theliquid conduit 192 includes acontrol valve 194. Thetop portion 170 of thefluid reservoir 130 includes agaseous conduit 196 fluidly coupled to a portion of thecasing 158 corresponding to the second set of pump stages 162 b. - During operation
multiphase fluid 126 enters the first and second set of pump stages 162 a and 162 b of thepump 128. Themultiphase fluid 126 is compressed along the one or more stages of the first and second set of pump stages 162 a and 162 b. A portion of themultiphase fluid 126 flowing along the first set of pump stages 162 a is extracted into thefluid reservoir 130 through one ormore slots 134 as discussed earlier. A remaining portion of themultiphase fluid 126 flowing along the first set of pump stages 162 a and themultiphase fluid 126 flowing along the second set of pump stages 162 b are compressed to generate the compressedmultiphase fluid 122. Thepump outlet 124 discharges the compressedmultiphase fluid 122 from thepump 128. In the embodiment shown, a portion of the extractedliquid phase 146 is fed from thefluid reservoir 130 into thesecond pump inlet 132 b via theliquid conduit 192. Thecontrol valve 194 may regulate a flow of the portion of the extractedliquid phase 146. Further, a portion of the extractedgaseous phase 148 may be fed from thefluid reservoir 130 into the second set of pump stages 162 b via thegaseous conduit 196. -
FIG. 6 represents aportion 197 of apump 128 in accordance with an exemplary embodiment. Theportion 197 has a plurality ofdiffusers 166 and aslot 134 defined in acasing 158. Theslot 134 is positioned corresponding to a mid-length of the plurality ofdiffusers 166 and has a width “W1”. Further, theslot 134 is a continuous slot having a uniform size along thecasing 158. In certain other embodiments, theslot 134 may be positioned anywhere between aleading edge 204 and a trailingedge 206 of the plurality ofdiffusers 166. Specifically, theslot 134 may be positioned at about 20 percent to about 80 percent of the length “L” of the plurality ofdiffusers 166. Theslot 134 may be configured to extract a portion of themultiphase fluid 126 from thepump 128 and to re-inject an extractedgaseous phase 148 into thepump 128. -
FIG. 7 represents aportion 199 of apump 128 in accordance with another exemplary embodiment. In the illustrated embodiment, aslot 134 defined in acasing 158 has a width “W2” different than the width “W1” as shown in the embodiment ofFIG. 6 . Theslot 134 having a smaller width may accurately regulate a quantity of amultiphase fluid 126 extracted into thefluid reservoir 130. Similar to the embodiment ofFIG. 6 , theslot 134 is a continuous slot having a uniform size along thecasing 158 and is positioned at a mid-length of a plurality ofdiffusers 166. -
FIG. 8 represents aportion 201 of apump 128 in accordance with yet another exemplary embodiment. Aslot 134 is located proximate to aleading edge 204 of a plurality ofdiffusers 166. Similar to the embodiment ofFIG. 6 , theslot 134 is a continuous slot having a uniform size along acasing 158.FIG. 9 represents aportion 203 of apump 128 in accordance with yet another exemplary embodiment. Aslot 134 is located proximate to a trailingedge 206 of a plurality ofdiffusers 166. Similar to the embodiment ofFIG. 6 , theslot 134 is a continuous slot having a uniform size along acasing 158. -
FIG. 10 represents a portion of 205 of apump 128 in accordance with yet another exemplary embodiment. Theportion 205 has one or morediscrete slots 134 defined in acasing 158. In the illustrated embodiment, eachslot 134 is positioned corresponding to a mid-length of a plurality ofdiffusers 166. Further, eachslot 134 has a width “W1” and covers a portion of apressure side 202 and asuction side 200 of at least onediffuser 166. As shown in the embodiments ofFIGS. 6, 7, 8 , and 9, eachslot 134 may have different width and may be positioned anywhere between aleading edge 204 and a trailingedge 206 of the plurality ofdiffusers 166. -
FIG. 11 represents a portion of 207 of apump 128 in accordance with yet another exemplary embodiment. Theportion 207 includes one or morediscrete slots 134 defined in acasing 158. In one embodiment, eachslot 134 is positioned proximate to a trailingedge 206. Eachslot 134 has a non-uniform size along thecasing 158 and is disposed between asuction side 200 of adiffuser 166 and apressure side 202 of a mutuallyadjacent diffuser 166. The shape and position of eachslot 134 may be chosen such that an extraction of themultiphase fluid 126 happens from an area of thediffuser 166 where themultiphase fluid 126 tends to re-circulate (or have more turbulence or is a stagnant flow) within thepump 128. Eachslot 134 removes the stagnant flow (i.e. low quality flow) from such area of thediffuser 166 to improvise an aero dynamic effect of themultiphase fluid 126 within thepump 128. -
FIG. 12 represents a portion 208 of afluid processing system 108 in accordance with an exemplary embodiment. The portion 208 illustrates adischarge device 144 in accordance to the exemplary embodiment. - The
discharge device 144 is an active device including a plurality ofconcentric cylinders 210 disposed at anopening 178 of there-circulation conduit 140. An outerconcentric cylinder 210 a among the plurality ofconcentric cylinders 210 has aside wall 212 rotatably engaged with anouter wall 214 of there-circulation conduit 140. Similarly, an innerconcentric cylinder 210 b among the plurality ofconcentric cylinders 210 has aside wall 216 coupled to acasing 158 of apump 128. Theside walls wall 219 of apump inlet 132. In one or more embodiments, the pre-determined angle “a” may be a negative angle, a positive angle, zero, or combination thereof depending on an application and design criteria. The plurality ofconcentric cylinders 210 is a hollow cylinder with eachcylinder 210 having one ormore holes 218 spaced apart from each other and disposed along a circumference of eachcylinder 210. The outerconcentric cylinder 210 a is coupled to an actuator (not shown inFIG. 12 ) for rotating (as designated by a reference number 217) thecylinder 210 a about an axis of theshaft 160. The innerconcentric cylinder 210 b is a stationary cylinder. In certain other embodiments, the outerconcentric cylinder 210 a may be stationary and the innerconcentric cylinder 210 b may be rotatable about the axis of theshaft 160. - During operation actuator may rotate the outer
concentric cylinder 210 a for aligning one ormore holes 218 a with one ormore holes 218 b of innerconcentric cylinder 210 b. Such alignment ofholes liquid phase 146 to flow through thedischarge device 144 into thepump inlet 132. The outerconcentric cylinder 210 a may be regulated via the actuator by an electronic control unit as discussed in the embodiment ofFIG. 1 . Theconcentric cylinders 210 may control a pressure and a quantity of the extractedliquid phase 146 being re-circulated into thepump 128. In one or more embodiments, suitable actuators may include motors. -
FIG. 13 represents aportion 209 of afluid processing system 108 in accordance with another exemplary embodiment. Theportion 209 illustrates adischarge device 144 in accordance to the exemplary embodiment. Thedischarge device 144 is an active device including avalve 220 disposed in apipe 222 which is coupled between are-circulation conduit 140 and apump inlet 132. As discussed in the embodiment ofFIG. 12 , thevalve 220 may be driven by an actuator to regulate intermediate re-circulation of an extractedliquid phase 146 into thepump inlet 132. -
FIG. 14 represents aportion 211 of asubsea system 100 in accordance to an exemplary embodiment. Theportion 211 illustrates adischarge device 144 and anactuator 225. Thedischarge device 144 is a passive device including avalve 224 disposed in apipe 222 coupled to are-circulation conduit 140 and apump inlet 132. Theactuator 225 is disposed in aconduit 232 coupled to afluid outlet 112 and thepipe 222 via anopening 230. Theactuator 225 is further coupled to thevalve 224. In the embodiment shown, theactuator 225 is a first piston including aspring 234 disposed between a piston head (not labeled) and theopening 230. - During operation a portion of a compressed
multiphase fluid 122 flows in theconduit 232 and a portion of an extractedliquid phase 146 flows in thepipe 222. Thefirst piston 225 is configured to reciprocate along theopening 230 to either engage or disengage thevalve 224 based on a pressure difference between thepipe 222 andconduit 232. For example, when a pressure applied by the compressedmultiphase fluid 122 in theconduit 232 is significantly greater than a pressure applied by the extractedliquid phase 146 in thepipe 222, thefirst piston 225 engages thevalve 224 and obstructs a flow of the extractedliquid phase 146 into thepump inlet 132. Similarly, when the pressure applied by the extractedliquid phase 146 in thepipe 222 is significantly greater than the pressure applied by the compressedmultiphase fluid 122 in theconduit 232, thefirst piston 225 disengages thevalve 224 and allows the flow of theliquid phase 146 into thepump inlet 132. - In certain embodiments, the
conduit 232 may further include a second piston (not shown inFIG. 14 ) disposed at anopening 113 formed in thefluid outlet 112. In such embodiments, theconduit 232 may be filled with a fluid such as oil and water, different than thecompressed fluid 112. The second piston may compress the fluid based on the pressure of the compressedmultiphase fluid 122 flowing in thefluid outlet 112 and thereby increase the pressure across thefirst piston 225 to engage thevalve 224. -
FIG. 15 represents aportion 213 of afluid processing system 108 in accordance with yet another exemplary embodiment. Theportion 213 illustrates adischarge device 144 in accordance to the exemplary embodiment. Thedischarge device 144 is a passive device including acylinder 236 disposed at anopening 178 of are-circulation conduit 140. Thecylinder 236 includes aside wall 240 coupled to acasing 158 and anouter wall 214 of afluid reservoir 130. Theside wall 240 is inclined at a pre-determined angle “a” relative to awall 219 of apump inlet 132. Thecylinder 236 is a hollow cylinder with one ormore holes 238 spaced apart from each other and disposed along a circumference of thecylinder 236. In the embodiment shown, thecylinder 236 is a stationary cylinder. During operation an extractedliquid phase 146 is re-circulated continuously from there-circulation conduit 140 into thepump inlet 132 via the one ormore holes 238. - In certain embodiments, the
side wall 240 is inclined at a zero angle relative to thewall 219 i.e. theside wall 240 is disposed substantially parallel to thewall 219. In such embodiments, thecylinder 236 may move up and/or down via an actuator, to either open and/or close a portion of theholes 238 for selectively allowing the extractedliquid phase 146 to flow into thepump inlet 132. -
FIG. 16 represents aportion 215 of afluid processing system 108 in accordance with yet another exemplary embodiment. Theportion 215 illustrates adischarge device 144 in accordance to the exemplary embodiment. Thedischarge device 144 is a passive device including acylinder 242 disposed at anopening 178 of afluid reservoir 130. Thecylinder 242 includes ahole 244 such as a slit, defined along a circumference of thecylinder 242. In the illustrated embodiment, thehole 244 is substantially perpendicular relative to awall 219 of apump inlet 132. During operation an extractedliquid phase 146 is re-circulated from are-circulation conduit 140 into thepump inlet 132 via thehole 244. - Similar to the embodiment discussed in
FIG. 15 , thecylinder 242 may move up and/or down via an actuator, to either open and/or close a portion of theslit 244 for selectively allowing theliquid phase 146 to flow into thepump inlet 132. - In accordance with certain embodiments discussed herein, a subsea system facilitates an efficient way of transporting a production fluid characterized by high gas volume fraction (gas slugs) from a subsea hydrocarbon reservoir to a distant storage facility. In doing so, the subsea system mixes a primer liquid with the production fluid primarily within an inlet tank to reduce a gas volume fraction (GVF) of the production fluid entering a pump and causing damage to the pump. Further, a fluid processing system of the present invention allows extraction of a portion of the multiphase fluid at an intermediate pressure from the pump, separation of a gaseous phase from a liquid phase, and intermediate re-circulation of the extracted liquid phase into the pump to further reduce the GVF of the multiphase fluid at the pump inlet thereby avoiding the further damage to the pump. The process of re-circulation of the primer liquid and the intermediate re-circulation of the extracted liquid phase may be automated by having a plurality of sensors and an electronic control unit.
- While only certain features of embodiments have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended embodiments are intended to cover all such modifications and changes as falling within the spirit of the invention.
Claims (21)
1. A fluid processing system comprising:
a pump including a casing, one or more pump stages, a pump inlet, and a pump outlet, the casing defining one or more slots, wherein at least one of the slots is configured to extract at least a portion of a multiphase fluid flowing within the pump, wherein each pump stage comprises a diffuser and an impeller; and
a fluid reservoir encompassing at least a portion of the casing and configured to receive and separate the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase,
wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet, and a discharge device coupled to the re-circulation conduit and configured to regulate re-circulation of at least a portion of the extracted liquid phase to the pump via the pump inlet so as to reduce a gas volume fraction (GVF) of the multiphase fluid being fed to the pump.
2. The system according to claim 1 , wherein the fluid reservoir further comprises a re-injection conduit coupled to the one or more pump stages upstream relative to the slots and configured to regulate re-injection of the extracted gaseous phase into the pump.
3. The system according to claim 1 , wherein the pump stages are arranged in a serial configuration.
4. The system according to claim 1 , wherein the pump stages are arranged in a parallel configuration.
5. The system according to claim 1 , wherein the one or more slots are located at about 20 percent to about 80 percent of a length of the diffuser.
6. The system according to claim 1 , wherein the one or more slots comprises at least one of a continuous slot, a discrete slot, a non-uniform slot.
7. The system according to claim 6 , wherein the one or more slots are positioned along at least one of a mid-chord length of the diffuser, a leading edge of the diffuser, and a trailing edge of the diffuser.
8. The system according to claim 1 , wherein the discharge device comprises a plurality of concentric cylinders with each cylinder having one or more holes for allowing the extracted liquid phase to flow through the discharge device.
9. The system according to claim 8 , wherein each cylinder comprises a side wall inclined at a pre-determined angle relative to the pump inlet, to regulate at least one a pressure and a quantity of extracted liquid phase being fed to the pump.
10. The system according to claim 1 , wherein the discharge device comprises a valve disposed in a pipe coupled between the re-circulation conduit and the pump inlet, for regulating a flow of the extracted liquid phase into the pump.
11. The system according to claim 1 , wherein the discharge device comprises a valve disposed in a pipe and coupled to an actuator disposed in a conduit, wherein the pipe is coupled to the re-circulation conduit and the pump inlet, and the conduit is coupled to the pipe and the fluid outlet, wherein the valve is configured to regulate a flow of the extracted liquid phase into the pump based on a pressure difference across the pump.
12. The system according to claim 1 , wherein the discharge device comprises a cylinder including one or more holes for allowing the extracted liquid phase to flow into the pump inlet.
13. The system according to claim 1 , wherein the discharge device comprises at least one of an active device and a passive device and configured to regulate a flow of the extracted liquid phase into the pump.
14. A method comprising:
introducing a multiphase fluid into a pump configured to increase pressure of the multiphase fluid, wherein the pump comprises a casing, one or more pump stages, a pump inlet, and a pump outlet, wherein each pump stage comprises a diffuser and an impeller;
extracting at least a portion of the multiphase fluid flowing within the pump into a fluid reservoir encompassing at least a portion of the casing via one or more slots defined in the casing, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit;
separating the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase;
re-circulating at least a portion of the extracted liquid phase through the re-circulation conduit into the pump via the pump inlet by regulating a flow of the extracted liquid phase via the discharge device; and
mixing the extracted liquid phase with the multiphase fluid at the pump inlet so as to reduce the gas volume fraction (GVF) of the multiphase fluid being fed to the pump.
15. The method of claim 14 , further comprising re-injecting the extracted gaseous phase into the one or more pump stages upstream relative to the slots via the re-injection conduit coupled to the fluid reservoir.
16. The method of claim 14 , wherein the regulating comprises controlling the discharge device having a plurality of concentric cylinders and one or more holes disposed on each cylinder, for allowing a flow of the extracted liquid phase into the pump.
17. The method of claim 14 , wherein the regulating comprises controlling the discharge device having a valve disposed in a pipe coupled between the re-circulation conduit and the pump inlet, for allowing a flow of the extracted liquid phase into the pump.
18. The method of claim 14 , wherein the regulating comprises controlling the discharge device having a valve coupled to an actuator, for allowing a flow of the extracted liquid phase into the pump based on a pressure difference across the pump, wherein the valve is disposed in a pipe and the actuator is disposed in a conduit, wherein the pipe is coupled to the re-circulation conduit and the pump inlet, and the conduit is coupled to the pipe and the fluid outlet.
19. A method comprising:
receiving a first production fluid in an inlet tank and mixing it with a primer liquid to produce thereby a second production fluid (multiphase fluid) having a reduced gas volume fraction (GVF) relative to the first production fluid;
introducing the multiphase fluid from the inlet tank into a pump configured to increase pressure of the multiphase fluid and produce thereby a compressed multiphase fluid, wherein the pump comprises a casing, one or more pump stages, a pump inlet, and a pump outlet, wherein each pump stage comprises a diffuser and an impeller;
extracting at least a portion of the multiphase fluid flowing within the pump into a fluid reservoir encompassing at least a portion of the casing via one or more slots defined in the casing, wherein the fluid reservoir comprises a re-circulation conduit disposed proximate to the pump inlet and a discharge device coupled to the re-circulation conduit;
separating the portion of the multiphase fluid into an extracted liquid phase and an extracted gaseous phase;
re-circulating at least a portion of the extracted liquid phase through the re-circulation conduit into the pump via the pump inlet by regulating a flow of the extracted liquid phase via the discharge device;
mixing the extracted liquid phase with the multiphase fluid at the pump inlet to further reduce the GVF of the multiphase fluid being fed to the pump; and
transporting the compressed multiphase fluid from the pump to a fluid storage facility via a fluid conduit.
20. The method according to claim 19 , further comprising re-injecting the extracted gaseous phase into the one or more pump stages upstream relative to the one or more slots via the re-injection conduit coupled to the fluid reservoir.
21. The method according to claim 19 , wherein the primer liquid comprises a liquid stream of the compressed multiphase fluid, which is delivered to the inlet tank via a re-circulation loop coupled to the fluid conduit, wherein the re-circulation loop comprises a control valve configured to regulate a flow of the liquid stream.
Priority Applications (1)
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US14/686,897 US20160138595A1 (en) | 2014-11-13 | 2015-04-15 | Subsea fluid processing system with intermediate re-circulation |
Applications Claiming Priority (2)
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US201462079125P | 2014-11-13 | 2014-11-13 | |
US14/686,897 US20160138595A1 (en) | 2014-11-13 | 2015-04-15 | Subsea fluid processing system with intermediate re-circulation |
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US20160138595A1 true US20160138595A1 (en) | 2016-05-19 |
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US14/686,897 Abandoned US20160138595A1 (en) | 2014-11-13 | 2015-04-15 | Subsea fluid processing system with intermediate re-circulation |
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WO (1) | WO2016077674A1 (en) |
Cited By (5)
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WO2019018781A1 (en) * | 2017-07-21 | 2019-01-24 | Forum Us, Inc. | Apparatus and method for regulating flow from a geological formation |
US20190169968A1 (en) * | 2017-12-01 | 2019-06-06 | Onesubsea Ip Uk Limited | Liquid retainer for a production system |
CN110905863A (en) * | 2018-09-17 | 2020-03-24 | 苏尔寿管理有限公司 | Multiphase pump |
EP3626930A1 (en) * | 2018-09-24 | 2020-03-25 | OneSubsea IP UK Limited | Subsea splitter pump system |
US11008848B1 (en) | 2019-11-08 | 2021-05-18 | Forum Us, Inc. | Apparatus and methods for regulating flow from a geological formation |
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US10208745B2 (en) | 2015-12-18 | 2019-02-19 | General Electric Company | System and method for controlling a fluid transport system |
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FR2774136B1 (en) * | 1998-01-28 | 2000-02-25 | Inst Francais Du Petrole | SINGLE SHAFT COMPRESSION-PUMP DEVICE ASSOCIATED WITH A SEPARATOR |
FR2783884B1 (en) * | 1998-09-24 | 2000-10-27 | Inst Francais Du Petrole | COMPRESSION-PUMPING SYSTEM COMPRISING AN ALTERNATING COMPRESSION SECTION AND A METHOD THEREOF |
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US7708059B2 (en) * | 2007-11-13 | 2010-05-04 | Baker Hughes Incorporated | Subsea well having a submersible pump assembly with a gas separator located at the pump discharge |
US20110048546A1 (en) * | 2008-04-21 | 2011-03-03 | Statoil Asa | Gas compression system |
US20150315884A1 (en) * | 2012-08-14 | 2015-11-05 | Aker Subsea As | Multiphase pressure boosting pump |
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WO2019018781A1 (en) * | 2017-07-21 | 2019-01-24 | Forum Us, Inc. | Apparatus and method for regulating flow from a geological formation |
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US20190169968A1 (en) * | 2017-12-01 | 2019-06-06 | Onesubsea Ip Uk Limited | Liquid retainer for a production system |
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CN110905863A (en) * | 2018-09-17 | 2020-03-24 | 苏尔寿管理有限公司 | Multiphase pump |
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