Carbon capture system and floating production platform

Abstract

The utility model relates to a kind of carbon capture system and floating production platform.Compared with prior art, in the carbon capture system of the utility model, the system is continuously stably supplied with the passageway of fuel to heat engine by first conveying passage, obtains a part of fuel before fuel combustion and is transported to first capture module to process capture, avoids all fuel to be sent into heat engine combustion, obtains higher concentration of carbon dioxide;Second conveying passage then at least part of flue gas is recycled and input to the inside of heat engine, improves carbon dioxide concentration level in flue gas;Formed the two-stage capture structure of combination of capture before combustion and capture after combustion, the process of processing capture before combustion can directly obtain high concentration of carbon dioxide, and capture after combustion can also obtain high concentration of carbon dioxide due to the flue gas recirculation, and capture operation under high concentration condition is conducive to substantially reducing the energy consumption level of capture, to realize the comprehensive energy consumption reduction of entire carbon capture system.

Description

Technical Field

[0001] This utility model relates to the field of floating platform carbon capture technology, and in particular to a carbon capture system and a floating production platform. Background Technology

[0002] Offshore floating production platforms are mobile oil and gas production facilities deployed in the marine environment. They enable integrated operations of oil and gas resource extraction, processing, storage, and transportation, and are suitable for complex marine areas such as deep water and ultra-deep water. These platforms are typically based on a hull or semi-submersible structure and integrate multiple functional units such as drilling, oil and gas separation, water treatment, oil and gas metering, flare systems, and living quarters. Through connections to subsea wellheads, subsea pipelines, and other facilities, they perform preliminary processing of extracted oil and gas to meet transportation or further processing requirements.

[0003] In terms of energy supply, offshore floating production platforms often utilize methane and other natural gas, which are byproducts of extraction, as fuel to drive gas turbines for power generation. Methane, a high-calorific-value clean energy source, produces high-temperature, high-pressure gas through combustion in the gas turbine. This gas drives the turbine blades to rotate at high speed, which in turn drives a generator to convert mechanical energy into electrical energy. This power generation method offers advantages such as rapid start-up, stable operation, and flexible power adjustment, providing continuous and reliable power support for various production equipment, living facilities, and control systems on the platform, ensuring its normal operation.

[0004] However, when methane is fully combusted with oxygen in a gas turbine, the main chemical reaction is CH4 + 2O2 → CO2 + 2H2O, which releases a large amount of carbon dioxide. If this carbon dioxide is directly emitted into the atmosphere, it will exacerbate the greenhouse effect and have a negative impact on the global climate and environment.

[0005] To reduce carbon emissions, carbon dioxide in the flue gas emitted by gas turbines needs to be captured. In the application scenario of offshore floating production platforms, a carbon capture device is usually added after the exhaust system of the gas turbine to treat the flue gas, separate the carbon dioxide, and compress and liquefy it for storage, so that it can be transported to land for storage or resource utilization.

[0006] However, the carbon capture process following gas turbine power generation suffers from high energy consumption, thus reducing the overall system's energy efficiency. Therefore, it is necessary to develop a novel carbon capture system and floating production platform to address the problems in these technologies. Utility Model Content

[0007] The purpose of this invention is to provide a carbon capture system and a floating production platform that can reduce the energy consumption of carbon capture.

[0008] The objective of this utility model can be achieved through the following technical solutions:

[0009] This utility model provides a carbon capture system for floating production platforms, comprising:

[0010] First conveying channel and second conveying channel;

[0011] The first delivery channel is used to obtain the fuel supplied by the platform to the heat engine;

[0012] The first capture module, connected to the first conveying channel, is used to process the fuel to obtain carbon dioxide;

[0013] The second conveying channel connects the exhaust channel and the intake channel of the heat engine, and is used to re-input at least part of the flue gas into the heat engine to increase the carbon dioxide concentration of the flue gas discharged by the heat engine;

[0014] The second capture module, connected to the heat engine, is used to process the flue gas to obtain carbon dioxide;

[0015] A storage device, connected to the first or second capture module, is used to store the obtained carbon dioxide.

[0016] Furthermore, the first capture module includes a reaction device, which comprises a methane steam reforming unit and a water-gas shift reaction unit connected in sequence, for processing the fuel to obtain reactants.

[0017] Furthermore, the first collection module also includes a separation device connected to the reaction device for separating carbon dioxide from the reactants.

[0018] Furthermore, the separation device is connected to the heat engine and is used to supply the separated reactants as fuel to the heat engine.

[0019] Furthermore, the separation device is a pressure swing adsorption device or a membrane separation device.

[0020] Furthermore, it also includes a steam generator, which is disposed between the exhaust channel of the heat engine and the second conveying channel, for recovering the heat of the flue gas to generate steam.

[0021] Furthermore, the steam generator is connected to the first or second capture module to provide the thermal energy required for capture.

[0022] Furthermore, the steam generator is connected to the steam turbine of the platform.

[0023] Furthermore, the fuel is methane, and the heat engine is a gas turbine.

[0024] This invention also provides a floating production platform, including the aforementioned carbon capture system.

[0025] Compared with existing technologies, the carbon capture system and floating production platform provided by this utility model have the following beneficial effects:

[0026] 1. The carbon capture system provided by this utility model consists of a first conveying channel that connects to a platform to continuously and stably supply fuel to a heat engine. Before combustion, a portion of the fuel is transported to the first capture module for processing and capture, preventing all fuel from being sent to the heat engine for combustion. Compared to post-combustion capture, this method of obtaining and capturing carbon dioxide before combustion produces a higher concentration of carbon dioxide. The second conveying channel connects between the exhaust and intake channels of the heat engine, recirculating at least a portion of the flue gas into the heat engine. This recirculation increases the carbon dioxide concentration in the final exhaust gas. The second capture module connects to the heat engine to capture the flue gas with the higher carbon dioxide concentration. This carbon capture system forms a two-stage capture structure combining pre-combustion and post-combustion capture. The pre-combustion processing capture process directly obtains a high concentration of carbon dioxide, while the post-combustion capture, due to flue gas recirculation, also obtains a high concentration of carbon dioxide. Capture operations under high concentration conditions significantly reduce the energy consumption of the capture process, thereby reducing the overall energy consumption of the entire carbon capture system and improving its overall economic and environmental benefits.

[0027] 2. The first collection module of this utility model includes a reaction device, which consists of a methane steam reforming device and a water-gas conversion reaction device connected in sequence, to perform multi-step chemical reaction treatment on the fuel to obtain a reaction mixture rich in carbon dioxide.

[0028] 3. The first collection module in this utility model is also equipped with a separation device, which is connected downstream of the reaction device and is used to accurately separate and extract high-purity carbon dioxide from the reaction mixture.

[0029] 4. In this utility model, the separation device is also connected to the fuel supply channel of the heat engine, so as to provide the remaining effective reactants after separation as supplementary fuel to the heat engine for use, thereby realizing the cascade utilization of energy.

[0030] 5. The separation device in this utility model adopts a pressure swing adsorption device or a membrane separation device, which can complete the gas separation task efficiently and with low energy consumption.

[0031] 6. This utility model also includes a steam generator, which is located at a key position between the exhaust channel and the second conveying channel of the heat engine. It utilizes the waste heat resources in the flue gas to generate steam, improving utilization efficiency, reducing energy consumption, and bringing economic benefits. Furthermore, utilizing the heat from the flue gas can reduce the number of other heat-generating devices on the floating platform, reducing space occupation and allowing for a more rational layout of the floating platform, alleviating the problem of limited space on floating platforms.

[0032] 7. In this utility model, the steam generator is also connected to the first or second capture module to provide the required thermal energy support for the capture process and realize the recycling of energy in the carbon capture system.

[0033] 8. In this utility model, the steam generator can also be connected to the steam turbine on the floating production platform to provide steam power for other power equipment on the platform, further improving the overall energy efficiency.

[0034] 9. In this utility model, the fuel is clean energy methane, and the heat engine is a gas turbine. The combination of the two can achieve low carbon emissions and high-efficiency power output. Attached Figure Description

[0035] Figure 1 This is a structural block diagram of the carbon capture system in an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the structure of the floating production platform in this embodiment of the present invention.

[0037] Figure label:

[0038] 1. First collection module; 11. Methane steam reforming unit; 12. Water-gas conversion reaction unit; 13. Separation unit; 4. Heat engine; 5. Steam generator; 6. Steam turbine; 7. Waste gas recirculation unit; 8. Second collection module; 9. Compression liquefaction unit; 10. Carbon dioxide storage tank. Detailed Implementation

[0039] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0040] This utility model embodiment provides a carbon capture system for floating production platforms, such as... Figure 1 As shown, it includes:

[0041] First conveying channel and second conveying channel;

[0042] The first delivery channel is used to obtain fuel supplied by the platform to the heat engine 4;

[0043] The first capture module 1 is connected to the first conveying channel and is used to process fuel to obtain carbon dioxide;

[0044] The second conveying channel connects the exhaust channel and the intake channel of the heat engine 4, and is used to re-input at least part of the flue gas into the heat engine 4 to increase the carbon dioxide concentration of the flue gas discharged from the heat engine 4.

[0045] The second capture module 8 is connected to the heat engine 4 and is used to process the flue gas to obtain carbon dioxide;

[0046] A storage device, connected to either the first capture module 1 or the second capture module 8, is used to store the obtained carbon dioxide.

[0047] Specifically, the conveying channels of the carbon capture system can be configured in a manner known to those skilled in the art, according to the needs of each component, and will not be elaborated further here. The pipelines of the conveying channels can use composite hoses, stainless steel pipelines, alloy pipelines, etc., or a combination of multiple pipelines, to meet the needs of conveying different substances, as well as to take into account the requirements of the floating platform's swaying environment and space utilization.

[0048] Specifically, refer to Figure 1 The storage device includes a compression liquefaction unit 9 and a carbon dioxide storage tank 10. The compression liquefaction unit 9 compresses, purifies, and liquefies the captured carbon dioxide, with purification processes including dehydration and desulfurization. Liquid carbon dioxide is formed through pressurized condensation and transported to the carbon dioxide storage tank 10 for storage via a conveying channel, reducing volume and space occupation. The carbon dioxide storage tank 10 can be transported to land via transportation facilities or directly to land facilities via a conveying channel; this invention does not impose any limitations on this.

[0049] Specifically, the first carbon capture module and the second carbon capture module can use technologies such as absorption, adsorption, and membrane separation to capture carbon. Their structures can be implemented using existing technologies known to those skilled in the art, so they will not be described in detail here.

[0050] Specifically, refer to Figure 1 A waste gas recirculation device 7 is installed on the second conveying channel. The flue gas is mixed with a certain amount of air through the second conveying channel and then reintroduced into the heat engine 4. A certain amount of air meets the combustion requirements. During the flue gas recirculation process, due to the smaller amount of air introduced, the amount of nitrogen introduced is reduced accordingly, while carbon dioxide gradually accumulates, and the proportion of carbon dioxide in the final exhaust gas increases.

[0051] Specifically, a carbon dioxide concentration detection sensor can be installed at the exhaust duct of the heat engine 4. When the carbon dioxide concentration reaches a predetermined concentration during the flue gas circulation process, the flue gas with a high carbon dioxide concentration is transported to the second collection module 8 via the steam generator 5.

[0052] Specifically, because the reactants produced by the fuel reaction in the reaction device have a high carbon dioxide concentration, the flue gas discharged after flue gas circulation has a high carbon dioxide concentration, which increases the absolute content of carbon dioxide in a unit volume of flue gas, thereby reducing the processing scale and equipment load of the first capture module 1 or the second capture module 8. The utilization rate of the medium during capture will also be higher, ultimately achieving a reduction in energy consumption for carbon capture.

[0053] In some embodiments of this utility model, reference is made to... Figure 1 The first collection module 1 includes a reaction device, which includes a methane steam reforming unit 11 and a water-gas shift reaction unit 12 connected in sequence, for processing fuel to obtain reactants.

[0054] Specifically, refer to Figure 1 The methane steam reforming unit 11 reforms the obtained natural gas fuel with steam to form a mixture of hydrogen and carbon monoxide. The carbon monoxide in the mixture is converted into carbon dioxide by the water-gas shift reaction unit 12, and finally a mixture of hydrogen and carbon dioxide is produced. The mixture is then transported to the separation unit 13 as a reactant.

[0055] In some embodiments of this utility model, reference is made to... Figure 1 The first collection module 1 also includes a separation device 13, which is connected to the reaction device and is used to separate carbon dioxide from the reactants.

[0056] Specifically, the separation device 13 can be a pressure swing adsorption device or a membrane separation device 13, or a combination of both. The separation device 13 separates carbon dioxide from the hydrogen and carbon dioxide mixture to obtain a high concentration of carbon dioxide gas, thereby achieving carbon dioxide capture and transporting it to a storage device.

[0057] In some embodiments of this utility model, the second collection module 8 can be a liquid absorption carbon collection device that uses a composite amine as the absorbent and a supergravity device as the absorption and desorption equipment.

[0058] In some embodiments of this utility model, reference is made to... Figure 1 The separation device 13 is connected to the heat engine 4 and is used to supply the separated reactants as fuel to the heat engine 4.

[0059] Specifically, refer to Figure 1 The hydrogen obtained by the separation device 13 from the reactants is transported to the heat engine 4 through the pipeline. The heat engine 4 operates using hydrogen and methane as fuel.

[0060] Specifically, a flow control device is also provided on the pipeline between the separation device 13 and the heat engine 4, thereby controlling the hydrogen blending ratio of the fuel input to the heat engine 4 to be between 5% and 20%, and the specific hydrogen blending ratio can be 5%, 8%, 11%, 14%, 17% or 20%.

[0061] In some embodiments of this utility model, reference is made to... Figure 1 It also includes a steam generator 5, which is located between the exhaust channel and the second conveying channel of the heat engine 4, and is used to recover the heat of the flue gas to generate steam.

[0062] Specifically, refer to Figure 1 After the steam generator 5 is installed, the flue gas of the heat engine 4 first passes through the steam generator 5 to provide heat, and then is reintroduced into the heat engine 4 through the second conveying channel and the waste gas recirculation device 7.

[0063] Specifically, a carbon dioxide concentration detection sensor can also be installed in the steam generator 5. After detecting that the carbon dioxide concentration of the flue gas input to the steam generator 5 reaches a predetermined concentration, the flue gas with a high carbon dioxide concentration is transported to the second collection module 8.

[0064] Specifically, the steam generator 5 uses at least part of the flue gas discharged from the heat engine 4 as a heat source, and raises the temperature of the water medium through heat transfer between the flue gas and the water medium, ultimately forming steam.

[0065] In some embodiments of this utility model, reference is made to... Figure 1 The steam generator 5 is connected to either the first capture module 1 or the second capture module 8 to provide the thermal energy required for capture.

[0066] Specifically, the steam generator 5 delivers a portion of the steam to the methane steam reforming unit 11 of the first collection module 1 via a pipeline, where the high-temperature steam reacts with methane to form hydrogen and carbon monoxide.

[0067] Specifically, the steam generator 5 delivers a portion of the steam to the water-gas conversion reactor 12 of the first capture module 1 via a pipeline to provide it with reaction heat.

[0068] Specifically, depending on the heat requirements of carbon capture, for example, if the first capture module 1 or the second capture module 8 uses chemical absorption for carbon capture, a large amount of heat energy is needed to heat the absorbent. Or, for example, the temperature-switching adsorption method requires continuous heating and cooling. The steam generator 5 delivers a portion of water vapor to the first capture module 1 or the second capture module 8 through the delivery pipeline to provide heat energy for carbon capture.

[0069] In some embodiments of this utility model, reference is made to... Figure 1 Steam generator 5 is connected to steam turbine 6 on the platform, and uses part of the steam to generate electricity.

[0070] In some embodiments of this utility model, the fuel is methane, and the heat engine 4 is a gas turbine.

[0071] This utility model embodiment also provides a floating production platform, such as Figure 2 As shown, including the carbon capture system described above, the floating production platform can be a floating production storage and offloading (FPSO) unit.

[0072] In other embodiments, the floating production platform may also be a floating liquefied natural gas (FLNG) production storage and offloading facility or other offshore oil and gas exploration and development facilities powered by natural gas.

[0073] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0074] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0075] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0076] In this utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0077] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0078] The preferred embodiments of this utility model have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of this utility model without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of this utility model through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A carbon capture system for a floating production platform, characterized in that, include: First conveying channel and second conveying channel; The first conveying channel is used to obtain the fuel supplied by the platform to the heat engine (4); The first capture module (1) is connected to the first conveying channel and is used to process the fuel to obtain carbon dioxide; The second conveying channel connects the exhaust channel and the intake channel of the heat engine (4) and is used to re-input at least part of the flue gas into the heat engine (4) to increase the carbon dioxide concentration of the flue gas discharged by the heat engine (4); The second capture module (8) is connected to the heat engine (4) and is used to process the flue gas to obtain carbon dioxide; A storage device, connected to the first capture module (1) or the second capture module (8), is used to store the obtained carbon dioxide.

2. The carbon capture system according to claim 1, characterized in that, The first collection module (1) includes a reaction device, which includes a methane steam reforming unit (11) and a water-gas conversion reaction unit (12) connected in sequence, for processing the fuel to obtain reactants.

3. The carbon capture system according to claim 2, characterized in that, The first collection module (1) further includes a separation device (13), which is connected to the reaction device and is used to separate carbon dioxide from the reactants.

4. The carbon capture system according to claim 3, characterized in that, The separation device (13) is connected to the heat engine (4) and is used to supply the separated reactants as fuel to the heat engine (4).

5. The carbon capture system according to claim 3, characterized in that, The separation device (13) is at least one of a pressure swing adsorption device or a membrane separation device (13).

6. The carbon capture system according to any one of claims 1 to 5, characterized in that, It also includes a steam generator (5), which is located between the exhaust channel of the heat engine (4) and the second conveying channel, for recovering the heat of the flue gas to generate steam.

7. The carbon capture system according to claim 6, characterized in that, The steam generator (5) is connected to the first collection module (1) or the second collection module (8) to provide the thermal energy required for collection.

8. The carbon capture system according to claim 6, characterized in that, The steam generator (5) is connected to the steam turbine (6) of the platform.

9. The carbon capture system according to claim 1, characterized in that, The fuel is methane, and the heat engine (4) is a gas turbine.

10. A floating production platform, characterized in that, Includes the carbon capture system as described in any one of claims 1 to 9.

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