AU2024329582A1 - Subsea utility gas generation - Google Patents

Abstract

A subsea oil and/or gas facility includes equipment/machinery located subsea, a noise mitigation system configured for subsea use, and a subsea gas generation system. The equipment/machinery includes pumping equipment/machinery having one or more pumps, or compression equipment/machinery having one or more compressors, or both, or any other subsea equipment for processing oil and/or gas generated by the subsea oil and/or gas facility. The noise mitigation system is configured to mitigate noise generated by the equipment/machinery and includes a resonator array including an array of inverted resonator cups configured to be filled with gas to mitigate the noise. The subsea gas generation system is configured to generate gas for the resonator array by electrolyzing water into hydrogen and oxygen gas as a source of the gas.

Description

SUBSEA UTILITY GAS GENERATION

TECHNICAL FIELD

[0001] The present disclosure relates generally to subsea noise mitigation and, more particularly, to a system and method for subsea gas generation for use in a subsea noise mitigation system having resonator array(s).

BACKGROUND

[0002] This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

[0003] Subsea noise, its sources and impacts are being increasingly scrutinized by nongovernmental organizations and regulators. Noise emissions from shipping, defense and other operations and their consequences are being increasingly documented and understood. The development of subsea oil and/or gas facilities and resultant deployment of underwater production trees, machinery and processing equipment on the seabed may generate long-term lower frequency noise that is transmissible over long distances. It may be desirable to reduce the noise output of such equipment.

[0004] The addition of an external matrix of resonator cups around the subsea machinery is one potential solution to mitigate noise output in subsea environments. However, one limitation of such a system is that the resonators must be gas filled to maintain noise mitigation performance on deepwater processing facilities. Therefore, it is presently recognized that a need exists for a system and method for providing gas to such resonators in a subsea environment.

SUMMARY OF THE INVENTION

[0005] A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.

[0006] In accordance with aspects of the disclosure, a subsea oil and/or gas facility includes equipment/machinery located subsea, a noise mitigation system configured for subsea use, and a subsea gas generation system. The equipment/machinery could include pumping equipment/machinery having one or more pumps, or compression equipment/machinery having one or more compressors, or both, or other equipment capable of producing noise levels that are considered to require mitigation for processing oil and/or gas generated by the subsea oil and/or gas facility. The noise mitigation system is configured to mitigate noise generated by the equipment/machinery. The noise mitigation system includes a resonator array configured for subsea use and including an array of resonator cups configured to be filled with gas to mitigate the noise. The subsea gas generation system is configured to generate gas for the resonator array by electrolyzing water into hydrogen and oxygen gas as a source of the gas. In certain embodiments, the hydrogen gas alone may be used as the gas source (since hydrogen is more stable than oxygen), with the oxygen gas being vented from the electrolysis process.

[0007] In accordance with another aspect of the disclosure, a method of mitigating noise produced in a subsea oil and/or gas facility is provided. The subsea oil and/or gas facility includes equipment/machinery located subsea and configured for subsea use, and the equipment/machinery could include pumping equipment/machinery having one or more pumps, or compression equipment/machinery having one or more compressors, or both, or other equipment capable of producing noise levels that are considered to require mitigation for processing oil and/or gas generated by the subsea oil and gas facility. The method includes deploying a subsea resonator array proximate the equipment/machinery, the subsea resonator array including an array of inverted resonator cups formed within resonator panels, the resonator cups being oriented to allow gas filling. The method includes generating gas for the subsea resonator array by electrolyzing water into hydrogen and oxygen via a subsea gas generation system. The method includes delivering the gas from the gas generation system to the subsea resonator array to fill the resonator cups with the gas for mitigating noise generated by the equipment/machinery during operation. BRIEF DESCRIPTION OF DRAWINGS

[0008] The drawings illustrate only example embodiments and are therefore not to be considered limiting in scope, as the example embodiments may admit to other equally effective embodiments. The elements and features shown in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the example embodiments. Additionally, certain dimensions or positions may be exaggerated to help visually convey such principles. In the drawings, reference numerals designate like or corresponding, but not necessarily identical, elements.

[0009] FIG. 1 is a block diagram of an example oil and/or gas facility utilizing a deepwater resonator array and gas generation system to mitigate noise associated with subsea equipment/machinery of the facility, in accordance with an embodiment of this disclosure.

[0010] FIG. 2 is a block diagram of an example of the subsea compressor system of FIG. 1 having a deepwater resonator array and a gas generation system coupled to a low voltage DC power supply, in accordance with an embodiment of this disclosure.

[0011] FIG. 3 is a partial schematic illustration showing the subsea compressor system of FIG.

1 fitted with a deepwater resonator array and a gas generation system, in accordance with an embodiment of this disclosure.

[0012] FIG. 4 is a block diagram of an example of the subsea compressor system of FIG. 1 having a deepwater resonator array and a gas generation system coupled to a source of thermally generated power, in accordance with an embodiment of this disclosure.

[0013] FIGS. 5 and 6 are schematic illustrations each showing a thermally generated power system that is configured to provide regenerative power to the electrolysis unit of a gas generation system, in accordance with an embodiment of this disclosure.

[0014] FIG. 7 is a process flow diagram illustrating a method that includes using two potential power sources for subsea gas generation to mitigate noise produced in a subsea oil and/or gas facility using a deepwater resonator array, in accordance with an embodiment of this disclosure.

DETAILED DESCRIPTION OF THE INVENTION

[0015] As set forth above, it may be desirable to mitigate noise generated by any one or a combination of underwater production trees, machinery and processing equipment on the seabed. Embodiments of the present disclosure may use gas bubble based acoustic resonators (e.g., Helmholtz resonators), for example as disclosed in U.S. Patent Nos. 8689935, 9343059, 9488026, and 9607601, which are incorporated by reference herein in their entirety. In some embodiments, the gas bubble based acoustic resonators, referred to herein as a resonator array may be, for example, a mesh or network of inverted cups that are at least partially filled with gas, creating gas voids that are specifically tuned to address specific frequencies of concern emitted from the equipment/machinery at a particular installation depth. The equipment/machinery that emits the frequencies of concern may include, by way of nonlimiting example, equipment/machinery such as a compressor module or pump module that are a part of a subsea installation. The resonator array may be adapted from shallow water use (e.g., 50 meters or less) to a deep water application (e.g., at least 1000 m) by encapsulating gas filled resonators arranged in a defined matrix or array - hereinafter referred to as a deepwater resonator array.

[0016] The deepwater resonator array requires the provision of gas to uniformly fill the individual cups of the array. Resonator cups must be gas filled to maintain noise mitigation performance on deepwater processing facilities by disrupting the sound waves emitted by subsea equipment / machinery. It is believed that no gas delivery mechanisms have been developed for this purpose, as the application of such arrays in deepwater environments continues to be developed.

[0017] While traditional gas sources such as compressed gas canisters may be utilized to fill the resonator cups, they represent a potential solution that would require regular replenishment or replacement of the canisters which can be time and resource intensive. Thus, it would be beneficial to have a system located in place to actively generate gas for the resonator cups on an on-demand basis. In accordance with present embodiments, a subsea system implements a water electrolysis process to split seawater into its component parts (oxygen & hydrogen) and distribute the resultant gas (e.g., the resultant hydrogen gas and/or the resultant oxygen gas) to uniformly fill the resonator cups within the noise mitigation system.

[0018] As may be appreciated, the subsea system may perform the electrolysis of water proceeding according to the following equation:

(1) H2O + electricity

[0019] In accordance with present embodiments, the source of the electricity used in this reaction may be supplied from the deployed equipment or produced on-site from the subsea system. While the current of electricity available for this reaction may vary based on, among other things, the temperature of the water that is electrolyzed, the electricity produced or otherwise routed from certain components of the present system may be low voltage direct current (LVDC) sufficient to drive the reaction.

[0020] The embodiments of this disclosure may encompass a variety of configurations, an example of which is depicted in FIG. 1, which is a block diagram of a subsea oil and/or gas facility 10. In FIG. 1, the subsea oil and/or gas facility 10 is an oil and/or gas production system (a hydrocarbon production system) utilizing subsea equipment with noise mitigation features, all of which is configured for subsea use. In particular, the subsea oil and/or gas facility 10, subsea equipment, and noise mitigation features may all be configured for deepwater use.

[0021] In the illustrated embodiment, the subsea oil and/or gas facility 10 includes a subsea processing station 12 that processes production fluids (e.g., oil, gas, or a mixture thereof) received from subsea production trees and manifolds 14. The processed production fluids generated by the subsea processing station 12 are transmitted to topsides equipment 16 by one or more flow lines 18 that cross a water line 20 (e.g., a shoreline or to a topside facility). The topsides equipment 16 may include, by way of non-limiting example, a liquefied natural gas (LNG) plant, a gathering and separation facility, a petroleum-fired power plant, or the like. The subsea oil and/or gas facility 10 may also include certain supporting features that are not shown, such as umbilicals and a local field control station (FCS) or other facility or structure above the waterline. Umbilicals may be used to transmit electrical power and/or signals, hydraulic power and/or signals, or both, between the subsea production trees and manifolds 14, the subsea processing station 12, or a combination, and the FCS or other topside facility.

[0022] The subsea processing station 12 as illustrated is positioned on the seabed 22 via one or more structures. Such structures may include one or more mud mats 24 and one or more structural frames 26. The subsea processing station 12 may include one or more systems (or modules) that process produced fluids, such as by separation, pumping, and/or compression. The one or more systems may include rotating equipment/machinery located subsea and configured for subsea use. Such rotating equipment/machinery may include pumping equipment/machinery (e.g., a pumping module) having one or more pumps, or compression equipment/machinery (e.g., a compression module) having one or more compressors, or both, for processing oil and/or gas generated by the subsea oil and/or gas facility 10. Other types of equipment/machinery may be present in the subsea processing station 12 (e.g., chokes) that generate noise subsea requiring mitigation. The illustrated subsea processing station 12 includes a fluid separation system 28 configured to separate produced fluids into its liquid components 30 and gaseous components 32, a subsea pumping system 34 configured to pump the liquid components 30, and a subsea compression system 36 configured to compress the gaseous components 32. Pressurized liquid 38 from the subsea pumping system 34 and compressed gas 40 from the subsea compression system 36 are transmitted through the flow lines 18 to the topsides equipment 16. Although not shown, in some embodiments there may be flowlines that recycle at least a portion of the pressurized liquid 38 and the compressed gas 40 back to the fluid separation system 28.

[0023] Each of the systems illustrated include their respective components that process the produced fluids in the station 12. Specifically, the fluid separation system 28 includes separation equipment 42. The subsea pumping system 34 includes one or more subsea pumps 46 (which may be part of one or more pumping modules); and the subsea compression system 36 includes one or more subsea compressors 50 (which may be part of one or more compression modules). The systems are supported by one or more structural frames 26 and accordingly the one or more mud mats 24 to secure and support the mass of installed equipment.

[0024] To mitigate at least some of the noise generated by the subsea pumps 46 and/or subsea compressors 50, the station 12 may include a noise mitigation system 54 configured for subsea use, or more particularly for deepwater use. The noise mitigation system 54 may be positioned in specific locations to disrupt sound waves generated by equipment/machinery noise at its source to avoid sound transmission over long distances - especially at lower frequencies. Various embodiments of the subsea oil and/or gas facility 10 may utilize any one or a combination of the noise mitigation systems 54 described herein. In the illustrated embodiment, the subsea compression system 36 includes one or more noise mitigation systems 54 located proximate (e.g., around) the subsea compressor(s) 50 (e.g., within a compression module assembly or on the subsea compressor housing).

[0025] During operation, the rotating equipment/machinery such as the pump(s) 46 and compressor(s) 50, or other subsea equipment, produce noise, and it may be desirable to mitigate the noise produced by any one or a combination of these. In accordance with the described embodiments, the subsea compression system 36 and the subsea pumping system 34 may each include one or more noise mitigation systems 54 located proximate (e.g., around) the equipment noise source (e.g., within the module assembly or on the subsea compressor/pump housing).

[0026] In accordance with present embodiments, the noise mitigation system 54 includes a resonator array 56 configured for subsea use (e.g., for deepwater use) and comprising an array of inverted resonator cups (e.g., 112 in FIG. 2) configured to contain the supplied gas to mitigate noise from the equipment/machinery. In addition, the noise mitigation system 54 includes a gas generation system 58 configured to generate gas that will uniformly fill the resonator cups of the resonator array 56. As noted, the gas generation system 58 is generally configured to perform water electrolysis, and to deliver gas generated from the electrolysis to the resonator cups of the resonator array 56. In particular, the gas generation system 58 is configured to generate gas for the resonator array 56 by electrolyzing ambient sea water into hydrogen and oxygen gas. The hydrogen gas may be used as a source of the gas for filling the resonator cups. In some embodiments, the oxygen gas may be used as a source of the gas for filling the resonator cups. Filling the resonator cups of the resonator array 56 forms resonators that absorb or otherwise disrupt noise generated during operation of the subsea pump(s) 46 and/or the subsea compressor(s) 50.

[0027] Although the components of the noise mitigation system 54 are only illustrated for the subsea compression system 36 in FIG. 1, it should be noted that in various different embodiments these components may be replicated for the subsea pumping system 34, or may be utilized for both the subsea compression system 36 and the subsea pumping system 34, or may only be associated with the subsea pumping system 34. In one particular embodiment, the system 10 only includes the noise mitigation system 54 associated with the subsea compression system 36. The noise mitigation system 54 may be permanently installed for the operating life (which may be on the order of 25-50 years) of the equipment/machinery for which it is mitigating noise. In some embodiments, as shown, a heat source 88 may be provided along a flowline of the compressed gas 40, or in some other location of the process system of FIG. 1.

[0028] The deepwater resonator array 56 of this disclosure may have any appropriate shape and material construction that is suitable for mitigating noise generated by the subsea equipment/machinery mentioned above and may depend on the configuration utilized. As the resonator array 56 is configured to be used in a subsea installation, the resonator array 56 may have a designed noise mitigation level at a water depth of at least 100 meters, at least 500 meters, at least 1000 meters, at least 1250 meters, at least 1500 meters, at least 2000 meters, or at least 2500 meters; for example between 1000 meters and 1500 meters, or between 2000 meters and 3200 meters. The resonator array 56 may be configured to mitigate noise at an operational (“dynamic”) design temperature of 2°C to 30 °C. Such a temperature range may allow the resonator array 56 to be pre-installed on certain types of equipment before final deployment at their ultimate subsea location. In one non-limiting embodiment, the resonator array 56 may be configured to mitigate noise at an operational temperature of between 25 °C and 30 °C at an operational depth of between 100 m and 150 m. In another non-limiting embodiment, the resonator array 56 may be configured to mitigate noise at an operational temperature of between 3 °C and 5 °C at an operational depth of between 1200 m and 1500 m. In a further non-limiting embodiment, the resonator array 56 may be configured to mitigate noise at an operational temperature of between 3 °C and 5 °C at an operational depth of up to 3200 m.

[0029] The configuration of the resonator panels (e.g., 110 of FIG. 32) of the resonator array 56 may include shape, thickness, and material construction selected such that the resonator array 56 is configured to attenuate noise having particular frequencies, such as the low frequency portion of the spectrum, the medium frequency portion of the spectrum, the high frequency portion of the spectrum, or any combination thereof. Generally, the resonator array 56 may be configured to attenuate noise having a frequency ranging from 5 Hz to 10,000 Hz. In an example, at least one resonator array 56 is configured to mitigate noise output from one or more pumps, the noise having a range of between 40 Hz and 700 Hz. In an example, at least one resonator array 56 is configured to mitigate noise output from one or more compressors in a range of between 600 Hz and 2500 Hz.

[0030] The components of or associated with the noise mitigation system 54 may be further appreciated with respect to FIGS. 2-5. In FIG. 2, the subsea oil and/or gas facility 10 as illustrated includes a subsea compression system 36 having the noise mitigation system 54. The subsea compression system 36 may include one or more compressors 50 that the noise mitigation system 54 surrounds and/or to which the noise mitigation system 54 is attached. The one or more compressors 50 may form part of a compression module having a compression module support structure and other equipment (e.g., piping, valves, instruments, cathodic protection, etc.).

[0031] As described above, the noise mitigation system 54 includes a resonator array 56 configured for subsea use and a gas generation system 58. As illustrated, the gas generation system 58 may have an electrolysis unit 80 and a gas delivery system 82. The electrolysis unit 80 may include but is not limited to one or more vessels including one or more electrolytic cells configured to perform water electrolysis via the known processes of alkaline electrolysis, membrane-based electrolysis (e.g., polymer electrolyte membrane (PEM) electrolysis), or high temperature steam electrolysis, or any combination thereof.

[0032] As noted, the electrolysis unit 80 generates hydrogen and oxygen gas from ambient seawater, which may be delivered to the resonator array 56 via the gas delivery system 82. The gas delivery system 82 may include at least one gas supply tube. The gas delivery system 82 may include, by way of non-limiting example, one or more gas supply tubes, gas delivery manifolds, headers, and so forth. [0033] An example embodiment of the resonator array 56, electrolysis unit 80, and gas delivery system 82 is illustrated in FIG. 3. FIG. 3 shows an example subsea compression system 36 having a noise mitigation system 54 disposed around the noise making equipment/machinery (e.g., compression module having one or more compressors). As illustrated, the noise mitigation system 54 includes a deepwater resonator array 56 and resonator array support structure (e.g., frame) 70. The frame 70 of the noise mitigation system 54 surrounds the compression module.

[0034] As shown in the illustrated embodiment, the deepwater resonator array 56 may include a plurality of panels 110 in which resonator cups 112 are formed. The plurality of panels 110 are attached to the frame 70 such that the deepwater resonator array 56 surrounds the compression module on at least one side. In the illustrated embodiment, the panels 110 are attached to the frame 70 such that the deepwater resonator array 56 surrounds the compression module on all four sides and the top (but not the bottom, which is located on a structure at the seabed). The frame 70 is configured to hold the plurality of panels 110 in a noise mitigation orientation in which the resonator cups 112 on the panels 110 each have an open end oriented toward the seabed to enable capture of gas for noise attenuation.

[0035] The deepwater resonator array 56 may include multiple groups of panels 110, to ensure the required coverage for noise mitigation, as shown. The panels 110 are connected to structural support elements, either rigidly through the frame 70 or movably via a resonator actuation system coupled to the frame 70 to allow periodic access and/or intervention to the retrievable elements within the compression module.

[0036] The panels 110 are hydraulically connected for uniform and efficient gas delivery. The gas delivery system 82 in this embodiment includes supply tubes 114 (coupled to a gas delivery header) for the working gas (e.g., hydrogen and/or oxygen), which is received from the electrolysis unit 80 and is distributed to multiple locations. As depicted, at least one supply tube 114 is provided for each resonator panel 110. In an example, each gas supply tube 114 may supply gas to a different resonator panel 110 of the noise mitigation system 54. In another example, a single gas supply tube 114 may supply gas to multiple resonator panels 110 of the noise mitigation system 54.

[0037] The plurality of panels 110 are precisely located and may be supported by a relatively rigid support frame 70 that ensures the require coverage of the resonator array assembly 56. The material construction of the resonator array 56, including the material forming the supply tubes 114 for the working gas, may depend on the frequencies that are targeted for noise mitigation, along with other considerations such as the temperatures and pressures at which the resonator array 56 may be used.

[0038] Although FIG. 3 shows the noise mitigation system 54 being used in the context of a subsea compression system 36, it should be understood that a similar arrangement of the noise mitigation system 54 (e.g., including multiple panels 110, gas delivery system 82, electrolysis unit 80, frame 70, and/or resonator actuation system(s), etc.) may be used with a subsea pumping system (e.g., 34 of FIG. 1) or any other equipment/machinery of a subsea oil and/or gas facility.

[0039] As noted above, the electrolysis unit 80 utilizes electricity to perform the electrolysis, and in accordance with present embodiments this electricity may be delivered in a number of ways. As depicted in FIG. 2, in some embodiments the source of electricity may include a low voltage direct current (LVDC) 84 that is provided by the subsea processing station 12 itself and/or from the topsides equipment 16 (e.g., via one or more umbilicals). Such configurations may include a wet mate and flying lead for transmission from the source of the LVDC power 84 to the electrolysis unit 80.

[0040] In other embodiments, as shown in FIG. 4, the system 10 may utilize electricity generation equipment located subsea and configured to recover energy to generate electricity for the electrolysis unit 80. In certain embodiments, for example, the system 10 may utilize waste heat to generate electricity for the electrolysis unit 80. The term “waste heat” used herein may refer to residual heat that is generated from one or more processes of the subsea system 10. The gas generation system 58 may include or be otherwise associated with an electricity generation system 86, which may include the use of a thermal recovery siphon or thermal energy harvesting, or a combination thereof as described with respect to FIGS. 5 and 6, respectively. The electricity generation system 86 may include features that integrate with a heat source 88 of the system 10 (which may include one heat source or multiple heat sources). The electricity generation system 86 may be configured to convert heat energy from the heat source(s) 88 into electricity for operating the electrolysis unit 80. The heat source 88 may include, by way of example, waste heat from process coolers that not only produce heat but, because the systems are located subsea, produce heated water.

[0041] Referring now to FIG. 5, the system 10 may include utilization of a process system discharge cooler module as the heat source 88, which produces waste heat to seawater (i.e., heated water) as a byproduct of cooling process streams (e.g., compressed gas) of the system 10. The electricity generation equipment 86 of FIG. 5 may include a plenum 130 to capture the waste heat and direct it into a thermal turbine generator 132 as shown. The plenum 130 may capture heated water 134 output from the heat source 88 and direct the heated water 134 to the thermal turbine generator 132. The thermal turbine generator 132 may then produce DC electrical current 136 (to power the electrolysis unit 80) from the output of heated seawater 138. The thermal turbine generator 132 may be electrically coupled to the electrolysis unit 80 to provide the generated DC electrical current 136 to the electrolysis unit 80. The plenum 130 may further direct a fraction of the heated seawater 138 into the electrolysis unit 80 for optimization of the electrolysis process.

[0042] The system 10 of FIG. 6 includes a similar configuration, but in addition to or in lieu of the thermal turbine generator 132 includes a thermal energy harvesting panel 150. As such, the electricity generation equipment 86 includes at least a plenum 130 and the thermal energy harvesting panel 150. The plenum 130 may capture heated water 134 output from the heat source 88 and direct the heated water 134 to the thermal energy harvesting panel 150. The thermal energy harvesting panel 150 may be positioned within the plenum 130 and may include one or more thermoelectric generator modules to produce the DC electrical current 136 utilizing the Seebeck effect (to power the electrolysis unit 80) from the output of warm water 138. The thermal energy harvesting panel 150 may be electrically coupled to the electrolysis unit 80 to provide the generated DC electrical current 136 to the electrolysis unit 80. The plenum 130 may further direct the warm water 138 into the electrolysis unit 80 for optimization of the electrolysis process.

[0043] FIG. 7 is a process flow diagram illustrating an example method 700 of mitigating noise produced in a subsea oil and/or gas facility. As discussed above, the subsea oil and/or gas facility includes equipment/machinery (e.g., pumping equipment/machinery having one or more pumps, compression equipment/machinery having one or more compressors, or both), or any other noise making subsea equipment, for processing oil and/or gas generated by the subsea oil and/or gas facility. The method 700 may include blocks 702-710 shown in FIG. 7. It should be noted that in certain embodiments, the method 700 may not include every step shown in FIG. 7, the method 700 may include additional steps not shown in FIG. 7, and/or the steps of the method 700 may be performed in different orders than shown in FIG. 7, without departing from the scope of this disclosure.

[0044] At block 702, the method 700 includes deploying a subsea resonator array proximate the equipment/machinery. The subsea resonator array includes an array of inverted resonator cups formed within resonator panels. The resonator cups are capable of being uniformly filled with gas. At block 704, the method 700 includes generating gas for the subsea resonator array by electrolyzing water into hydrogen and oxygen via a gas generation system. Electrolyzing water into hydrogen and oxygen may be performed using alkaline electrolysis, membrane electrolysis, or high temperature electrolysis, or a combination thereof. At block 706, the method 700 includes delivering the hydrogen gas (and/or the oxygen gas) from the gas generation system to the subsea resonator array to fill the resonator cups with the gas to ensure their functionality to mitigate noise. When filled, the resonators are configured to mitigate noise generated by the equipment/machinery during operation.

[0045] As shown at block 708, the method 700 may include routing a low voltage direct current (LVDC) from a subsea processing station, topsides equipment, or a combination thereof to the gas generation system to power the electrolyzing process of block 704. As shown at block 710, the method 700 may include generating low voltage direct current (LVDC) electricity subsea and using the ‘in situ’ generated electricity to power the electrolyzing process of block 704. Subsea electricity generation (710) may include, for example, converting waste heat energy to electrical energy to generate the electricity. The surplus heat energy from the process will be converted to heated seawater, a portion of which can be supplied to the electrolysis unit to optimize performance of the electrolyzing process of block 704. In certain embodiments, the subsea electricity generation (710) may include cooling a process stream via a cooler, producing waste heat and hot water as a byproduct of the cooling process, and supplying electrical energy generated from the waste heat and warm water to the electrolysis unit. As described with reference to FIG. 5 above, the subsea electricity generation (710) may include capturing heat and water via a plenum and providing the heated water to a thermal turbine generator to generate the electricity. As described with reference to FIG. 6 above, the subsea electricity generation (710) may include capturing the waste energy from heated seawater via a plenum to provide thermal energy to the harvesting panel to generate electricity.

[0046] It will be understood that various modifications may be made to the embodiments disclosed herein. Therefore, the above description should not be construed as limiting, but merely as exemplifications of example embodiments. For example, the functions described above and implemented as the best mode for operating the present invention are for illustration purposes only. Other arrangements and methods may be implemented by those skilled in the art without departing from the scope and spirit of this invention. Moreover, those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto.

Claims

1. A subsea oil and/or gas facility comprising: equipment/machinery located subsea, the equipment/machinery comprising pumping equipment/machinery having one or more pumps, or compression equipment/machinery having one or more compressors, or both, or any other subsea equipment for processing oil and/or gas generated by the subsea oil and/or gas facility; a noise mitigation system configured for subsea use and configured to mitigate noise generated by the equipment/machinery, wherein the noise mitigation system comprises a resonator array configured for subsea use and comprising an array of inverted resonator cups configured to be filled with gas to mitigate the noise; and a subsea gas generation system configured to generate gas for the resonator array by electrolyzing water into hydrogen and oxygen gas as a source of the gas.

2. The subsea oil and/or gas facility of claim 1, further comprising an electrical power supply coupled to the gas generation system and configured to supply low voltage DC current (LVDC) for the electrolyzing process.

3. The subsea oil and/or gas facility of claim 2, wherein the electrical power supply supplies LVDC from a subsea processing station, topsides equipment, or a combination thereof.

4. The subsea oil and/or gas facility of claim 2, wherein the electrical power source comprises electricity generation equipment located subsea and configured to recover wasted energy from a process system to generate electricity.

5. The subsea oil and/or gas facility of claim 4, further comprising a heat source within the process system, wherein the electrical power source is configured to convert heat energy from the heat source into electricity.

6. The subsea oil and/or gas facility of claim 5, wherein the heat source is a process cooler located subsea, the process cooler being configured to produce waste heat energy via heated water.

7. The subsea oil and/or gas facility of claim 6, wherein the electrical power generation equipment comprises a thermal turbine generator to collect a portion of the waste heat energy within a plenum.

8. The subsea oil and/or gas facility of claim 6, wherein the electrical power generation equipment comprises a thermal energy harvesting panel to collect a portion of the waste heat energy within a plenum.

9. The subsea oil and/or gas facility of claim 1, further comprising a gas delivery system configured for subsea use and configured to deliver the gas from the gas generation system to the noise mitigation system, the gas delivery system having at least one gas supply tube.

10. The subsea oil and/or gas facility of claim 9, wherein: the noise mitigation system comprises a plurality of resonator arrays, the gas delivery system comprises multiple gas supply tubes, and each gas supply tube supplies gas to maintain utility gas level in a corresponding resonator array of the noise mitigation system.

11. The subsea oil and/or gas facility of claim 9, wherein: the noise mitigation system comprises a plurality of resonator arrays, and a single gas supply tube supplies gas to maintain utility gas level in the multiple resonator arrays of the noise mitigation system.

12. A method of mitigating noise produced in a subsea oil and/or gas facility comprising equipment/machinery located subsea and configured for subsea use, the rotating equipment/machinery comprising pumping equipment/machinery having one or more pumps, or compression equipment/machinery having one or more compressors, or both, or any other subsea equipment for processing oil and/or gas generated by the subsea oil and gas facility, the method comprising: deploying a subsea resonator array proximate the equipment/machinery, the subsea resonator array comprising an array of inverted resonator cups formed within resonator panels, the resonator cups being capable of being uniformly filled with gas; generating hydrogen gas for the subsea resonator array by electrolyzing water into hydrogen and oxygen via a subsea gas generation system; and delivering the hydrogen gas and/or the oxygen gas from the gas generation system to the subsea resonator array to uniformly fill the resonator cups with the gas to ensure resonator functionality to mitigate noise generated by the equipment/machinery during operation.

13. The method of claim 12, further comprising routing a low voltage direct current (LVDC) from a subsea processing station, topsides equipment, or a combination thereof to the gas generation system to power the electrolyzing process.

14. The method of claim 12, further comprising generating low voltage direct current (LVDC) electricity subsea and using the generated electricity to power the electrolyzing process.

15. The method of claim 14, further comprising converting heat energy to electrical energy via an in-situ electricity generation system to generate the electricity from installed process equipment.

16. The method of claim 15, further comprising outputting warm water as a byproduct of converting the heat energy to electrical energy and supplying the warm water to an electrolysis unit to optimize the electrolyzing process.

17. The method of claim 16, further comprising cooling a process stream via a cooler, producing waste heat energy via heated seawater as a byproduct of the cooling process, and supplying this waste heat energy to power the electricity generation system.

18. The method of claim 16, further comprising capturing heat energy via heated seawater via a plenum and providing this heat energy to power a thermal turbine generator to generate the electricity.

19. The method of claim 16, further comprising capturing heat energy via heated seawater via a plenum and providing this heat energy to power a thermal energy harvesting panel to generate the electricity.

20. The method of claim 12, wherein electrolyzing water into hydrogen and oxygen is performed using alkaline electrolysis, membrane electrolysis, or high temperature electrolysis, or any combination thereof.