Methanol preparation system, peak shaving control method and device for thermal power plant, and computer equipment

Abstract

The application provides a methanol preparation system, a thermal power plant peak regulation control method and device, and a computer device. The methanol preparation system comprises a thermal power plant, an SOEC hydrogen production system, a methanol synthesis system, a first heat exchanger, a second heat exchanger and a gas separation device; a water vapor pipeline of the thermal power plant is connected with a first heat exchange end of the first heat exchanger, and a second heat exchange end of the first heat exchanger is connected with the SOEC hydrogen production system; a combustion exhaust pipeline of the thermal power plant is connected with the gas separation device, the gas separation device is used for separating carbon dioxide and other gases from the combustion exhaust, and the separated carbon dioxide is used as raw material for methanol synthesis of the methanol synthesis system; a first heat exchange end of the second heat exchanger is arranged between the combustion exhaust pipeline and the gas separation device, and a second heat exchange end of the second heat exchanger is connected with the SOEC hydrogen production system; and the SOEC hydrogen production system is used for producing hydrogen, and the produced hydrogen is used as raw material for methanol synthesis of the methanol synthesis system.

Description

Technical Field

[0001] This application relates to the field of energy conservation and emission reduction technology, and in particular to a methanol preparation system, a peak-shaving control method and apparatus for thermal power plants, computer equipment and storage medium. Background Technology

[0002] With rapid societal development, greenhouse gas emissions from human life and production activities are constantly increasing, exacerbating the global greenhouse effect and threatening human survival. Carbon dioxide emission reduction is one of the most pressing issues that countries worldwide urgently need to address. While the growth rate of clean power generation capacity is high due to the development of new energy technologies, new energy sources are intermittent and fluctuating. Therefore, in many countries, thermal power plants still account for a large proportion of installed capacity and remain the mainstay of the power system. These thermal power plants often use fossil fuels such as coal and natural gas, resulting in significant carbon dioxide emissions. Therefore, given the current irreplaceable role of thermal power plants, reducing their carbon dioxide emissions is a crucial direction for power system improvement. Summary of the Invention

[0003] The purpose of this application is to address at least one of the aforementioned technical deficiencies, particularly the problem of high carbon dioxide emissions from existing thermal power plants that cannot be reused.

[0004] In one aspect, this application provides a methanol production system, including a thermal power plant, an SOEC hydrogen production system, a methanol synthesis system, a first heat exchanger, a second heat exchanger, and a gas separation device;

[0005] The steam pipeline of the thermal power plant is connected to the first heat exchange end of the first heat exchanger, and the second heat exchange end of the first heat exchanger is connected to the SOEC hydrogen production system to output the waste heat generated by steam condensation to the SOEC hydrogen production system.

[0006] The combustion exhaust gas pipeline of the thermal power plant is connected to a gas separation device, which is used to separate carbon dioxide and other gases from the combustion exhaust gas, and uses the separated carbon dioxide as a raw material for methanol synthesis in the methanol synthesis system.

[0007] The first heat exchange end of the second heat exchanger is located between the combustion exhaust gas pipeline and the gas separation device, and the second heat exchange end of the second heat exchanger is connected to the SOEC hydrogen production system to output the cooling waste heat of the combustion exhaust gas to the SOEC hydrogen production system.

[0008] The SOEC hydrogen production system is used to produce hydrogen, which is then used as a raw material for methanol synthesis in the methanol synthesis system.

[0009] In one embodiment, the SOEC hydrogen production system further includes an auxiliary heating device for heating the SOEC hydrogen production system when the waste heat provided by the thermal power plant through the first and second heat exchangers is insufficient to raise the operating temperature of the SOEC hydrogen production system to the target temperature range.

[0010] In one embodiment, the SOEC hydrogen production system is powered by a thermal power plant.

[0011] In one embodiment, the methanol preparation system further includes a dust collector, which is located before the gas separation device and is used to remove dust from the combustion exhaust gas before it enters the gas separation device.

[0012] In one embodiment, the SOEC hydrogen production system includes an SOEC hydrogen production reactor, an oxygen purification unit, a hydrogen purification unit, an oxygen compression unit, a hydrogen compression unit, an oxygen storage tank, and a hydrogen storage tank.

[0013] The SOEC hydrogen production reactor is connected to both an oxygen purification unit and a hydrogen purification unit for electrolysis of water to produce hydrogen and oxygen.

[0014] The hydrogen purification unit is connected to the hydrogen compression unit to purify hydrogen and output the purified hydrogen to the hydrogen compression unit.

[0015] The hydrogen compression device is connected to the hydrogen storage tank and is used to compress hydrogen and store it in the hydrogen storage tank.

[0016] The oxygen purification device is connected to the oxygen compression device to purify oxygen and output the purified oxygen to the oxygen compression device.

[0017] The oxygen compressor is connected to the oxygen storage tank and is used to compress oxygen and store it in the oxygen storage tank.

[0018] In one embodiment, the methanol production system further includes a carbon dioxide compression device and a carbon dioxide storage tank;

[0019] The carbon dioxide compression device is connected to the gas separation device and the carbon dioxide storage tank respectively, and is used to compress the carbon dioxide output from the gas separation device and store it in the carbon dioxide storage tank.

[0020] Secondly, this application provides a peak-shaving control method for a thermal power plant, applied to the thermal power plant in the methanol preparation system of any of the above embodiments. The peak-shaving control method for the thermal power plant includes:

[0021] In response to the downward peak shaving command, determine the power to be shaving;

[0022] Determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system;

[0023] If so, the output of the thermal power plant generator set will be reduced according to the portion of the power to be adjusted that exceeds the maximum absorption capacity, and the power will be supplied to the SOEC hydrogen production system according to the maximum absorption capacity.

[0024] If not, power is supplied to the SOEC hydrogen production system according to the power to be adjusted.

[0025] Thirdly, this application provides a peak-shaving control device for a thermal power plant, applied to the thermal power plant in the methanol preparation system of any of the above embodiments. The peak-shaving control device for the thermal power plant includes:

[0026] The command response module responds to the downward peak adjustment command and determines the power to be adjusted.

[0027] The judgment module is used to determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system.

[0028] The first control module is used to reduce the output of the thermal power plant generator set according to the portion of the power exceeding the maximum absorption capacity when it is determined that the power to be adjusted exceeds the maximum absorption capacity, and to supply power to the SOEC hydrogen production system according to the maximum absorption capacity.

[0029] The second control module is used to supply power to the SOEC hydrogen production system according to the power to be adjusted when it is determined that the power to be adjusted does not exceed the maximum absorption capacity.

[0030] Fourthly, this application provides a computer device including one or more processors and a memory storing computer-readable instructions. When the computer-readable instructions are executed by one or more processors, they perform the steps of the power plant peak-shaving control method described in the above embodiments.

[0031] Fifthly, this application provides a storage medium storing computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to perform the steps of the power plant peak-shaving control method described in the above embodiments.

[0032] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0033] Based on the methanol production system in this embodiment, the high-temperature steam and waste heat from the high-temperature combustion exhaust gas generated during the power generation process of the thermal power plant are released into the SOEC hydrogen production system through the first and second heat exchangers, respectively, effectively improving energy utilization. Simultaneously, using the hydrogen produced by the SOEC hydrogen production system and the large amount of carbon dioxide emitted by the thermal power plant as raw materials, methanol is produced in the methanol synthesis system. This effectively reduces carbon emissions from coal-fired power plants and yields a product that can serve as an important chemical raw material and energy storage medium, possessing high environmental and economic value. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the structure of a methanol preparation system provided in one embodiment of this application;

[0036] Figure 2 This is a schematic diagram of the structure of waste heat recovery in a thermal power plant provided in one embodiment of this application;

[0037] Figure 3 A schematic flowchart of a peak-shaving control method for a thermal power plant provided in one embodiment of this application;

[0038] Figure 4 This is a schematic diagram of a peak-shaving control device for a thermal power plant provided in one embodiment of this application;

[0039] Figure 5 This is an internal structural diagram of a computer device provided in one embodiment of this application. Detailed Implementation

[0040] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0041] This application provides a methanol preparation system; please refer to [link / reference]. Figure 1 and Figure 2The system includes a thermal power plant 100, an SOEC (Solid Oxide Electrolysis Cell) hydrogen production system 200, a methanol synthesis system 300, a first heat exchanger 102, a second heat exchanger 104, and a gas separation device 106. The thermal power plant 100, as described in this application, refers to a system where coal, natural gas, or oil is burned in a boiler 108 to heat the boiler, which then heats water in pipelines to generate high-temperature, high-pressure steam. This steam drives a turbine 110, which in turn drives a generator 112 to produce electricity. The SOEC hydrogen production system 200 utilizes a solid oxide electrolysis cell to electrolyze water at high temperatures (generally 600-1000℃) to produce hydrogen. This application considers that during the power generation process of the thermal power plant 100, both the combustion of waste gas and the high-temperature steam driving the turbine 110 have a considerable amount of waste heat that can be utilized. Since the SOEC hydrogen production system 200 needs to operate in a high-temperature environment, this application provides space for the utilization of the waste heat from the thermal power plant 100, such as… Figure 1 As shown, taking a coal-fired power plant 100 as an example, the waste heat from the coal-fired power generation process can be directly supplied to the SOEC hydrogen production system 200 to generate hydrogen. In some embodiments, the SOEC hydrogen production system 200 and the power plant 100 are located in the same area. To reduce line losses caused by dispatching power from other areas, the SOEC hydrogen production system 200 can be directly powered by the power plant 100. In some embodiments, if the waste heat provided by the power plant 100 is insufficient to maintain the SOEC hydrogen production system 200 at a suitable production temperature, it can be supplemented by an external heat source. Methanol (CH3OH) is an important chemical raw material that can be used to synthesize olefins, dimethyl ether, and other chemical products. It is also an important energy storage medium that can be used for power generation in fuel cells. One of the mainstream methods for preparing methanol is to produce methanol from carbon dioxide and hydrogen under the action of a catalyst. This method can effectively utilize the carbon dioxide produced by the thermal power plant 100 and the hydrogen produced by the SOEC hydrogen production system 200, converting the greenhouse gases produced by the thermal power plant 100 into clean energy, which helps to achieve low carbon emissions or even negative carbon emissions from the thermal power plant 100.

[0042] The structure for waste heat utilization mentioned above can be found in [reference needed]. Figure 2Specifically, the steam pipeline of the thermal power plant 100 is connected to the first heat exchange end of the first heat exchanger 102, and the second heat exchange end of the first heat exchanger 102 is connected to the SOEC hydrogen production system 200 (not shown in the figure). This is to output the waste heat generated by the condensation of steam to the SOEC hydrogen production system 200. It can be understood that liquid water flows in from the steam pipeline, is heated by the boiler 108 and converted into high-temperature, high-pressure steam, which flows along the steam pipeline and passes through the turbine 110. The steam drives the turbine 110, which in turn drives the generator 112, finally outputting electricity. Although the temperature of the steam flowing out of the turbine 110 drops to some extent, a large amount of residual heat can still be utilized. Therefore, the steam pipeline guides the steam flowing out of the turbine 110 to the first heat exchange end of the first heat exchanger 102. The steam cools and condenses into liquid at the first heat exchange end, releasing heat to the SOEC hydrogen production system 200 through the second heat exchange end of the first heat exchanger 102. The recondensed water can then be reintroduced into the boiler 108 for heating, achieving water recycling.

[0043] The first heat exchange end of the second heat exchanger 104 is located between the combustion exhaust gas pipeline and the gas separation device 106, and the second heat exchange end of the second heat exchanger 104 is connected to the SOEC hydrogen production system 200 (not shown in the figure) to output the cooling waste heat of the combustion exhaust gas to the SOEC hydrogen production system 200. It can be understood that the heat loss of the boiler 108 of the thermal power plant 100 is an important factor affecting the efficiency of the boiler 108 of the generator 112 group, among which the flue gas heat loss is the largest, accounting for 70%-80% of the heat loss of the boiler 108. The high-temperature exhaust gas generated by coal combustion in this application transfers heat to the SOEC hydrogen production system 200 through the second heat exchanger 104.

[0044] After passing through the second heat exchanger 104, the high-temperature exhaust gas enters the gas separation device 106. The gas separation device 106 separates carbon dioxide and other gases from the combustion exhaust gas, and the separated carbon dioxide is used as a feedstock for methanol synthesis in the methanol synthesis system 300. The SOEC hydrogen production system 200 utilizes the waste heat generated during power generation at the thermal power plant 100 for an electrolytic hydrogen production process, and the produced hydrogen is used as a feedstock for methanol synthesis in the methanol synthesis system 300. The electrolytic hydrogen production process also yields oxygen as a byproduct.

[0045] The methanol synthesis system 300 utilizes carbon dioxide recovered from coal-fired power plants to react with hydrogen produced by SOEC electrolysis of water to synthesize methanol. The crude product can be further separated and purified, and the resulting pure methanol can be sold externally or transported to remote areas such as isolated islands for use in fuel cell power generation.

[0046] Based on the methanol production system in this embodiment, the high-temperature steam and waste heat from the power generation process of the thermal power plant 100 are released into the SOEC hydrogen production system 200 through the first heat exchanger 102 and the second heat exchanger 104, respectively, effectively improving energy utilization. Simultaneously, using the hydrogen produced by the SOEC hydrogen production system 200 and the large amount of carbon dioxide emitted by the thermal power plant 100 as raw materials, methanol is synthesized in the methanol synthesis system 300. This effectively reduces carbon emissions from the coal-fired power plant and yields a product that can serve as an important chemical raw material and energy storage medium, possessing high environmental and economic value.

[0047] In one embodiment, the SOEC hydrogen production system 200 further includes an auxiliary heating device for heating the SOEC hydrogen production system 200 when the waste heat provided by the thermal power plant 100 through the first heat exchanger 102 and the second heat exchanger 104 is insufficient to raise the operating temperature of the SOEC hydrogen production system 200 to the target temperature range.

[0048] It is understandable that the target temperature range refers to the temperature range required for the SOEC hydrogen production system 200 to perform the water electrolysis hydrogen production reaction. Since the waste heat generated by the thermal power plant 100 is not a stable heat source, and the hydrogen production reaction has relatively strict temperature requirements, an auxiliary heating device can be installed in the SOEC hydrogen production system 200 to ensure the stable progress of the reaction. This auxiliary heating device will maintain the temperature of the SOEC hydrogen production system 200 within the target temperature range when the waste heat provided by the first heat exchanger 102 and the second heat exchanger 104 is insufficient.

[0049] In one embodiment, please refer to Figure 2 The methanol preparation system also includes a dust collector 114, which is located before the gas separation device 106 and is used to remove dust from the combustion exhaust gas as it enters the gas separation device 106.

[0050] In one embodiment, the SOEC hydrogen production system 200 includes an SOEC hydrogen production reactor, an oxygen purification unit, a hydrogen purification unit, an oxygen compression unit, a hydrogen compression unit, an oxygen storage tank, and a hydrogen storage tank.

[0051] The SOEC hydrogen production reactor is connected to both an oxygen purification unit and a hydrogen purification unit for water electrolysis to produce hydrogen and oxygen. The main components of the SOEC hydrogen production reactor are the electrolyte, cathode, and anode. The cathode is where the feed water decomposes, producing oxygen ions and hydrogen. The oxygen ions are conducted to the anode through the electrolyte, where they lose electrons to produce oxygen gas. Another function of the electrolyte is to prevent hydrogen gas from the cathode from seeping into the anode; therefore, the electrolyte layer has high airtightness, isolating the gases produced at the cathode and anode. Since the products produced at the cathode and anode are different, they can be collected at different electrodes and transported to their respective purification units for further purification.

[0052] The hydrogen purification unit is connected to the hydrogen compression unit to purify hydrogen and output the purified hydrogen to the compression unit. It can be understood that the hydrogen purification unit can purify hydrogen based on methods such as pressure swing adsorption (PSA), cryogenic separation (low-temperature distillation), membrane separation, chromatographic separation, and absorption. Among these, pressure swing adsorption is currently the most widely used hydrogen purification method due to its high product purity and moderate equipment investment cost.

[0053] A hydrogen compression unit is connected to a hydrogen storage tank to compress hydrogen and store it in the tank. The hydrogen storage tank can be connected to a methanol synthesis system 300, which can extract hydrogen from the storage tank for methanol synthesis as needed. Besides supplying the methanol synthesis system 300, the hydrogen in the storage tank can also be used as a product of the entire system.

[0054] The oxygen purification unit is connected to the oxygen compression unit to purify oxygen and output the purified oxygen to the oxygen compression unit. It is understandable that the oxygen purification method can be selected by combining its physical and chemical properties.

[0055] An oxygen compressor is connected to an oxygen storage tank to compress and store oxygen. If the thermal power plant is equipped with equipment related to oxy-fuel combustion technology, the oxygen in the storage tank can serve as the oxygen source for oxy-fuel combustion.

[0056] In one embodiment, the methanol production system further includes a carbon dioxide compression device and a carbon dioxide storage tank. The carbon dioxide compression device is connected to both the gas separation device 106 and the carbon dioxide storage tank, and is used to compress the carbon dioxide output from the gas separation device 106 and store it in the carbon dioxide storage tank. The carbon dioxide storage tank can be connected to the methanol synthesis system 300, which can extract carbon dioxide from the carbon dioxide storage tank for methanol synthesis as needed.

[0057] In one embodiment, the methanol synthesis system 300 may include a methanol synthesis reactor, a methanol separator, a compressor, etc. In the methanol synthesis, carbon dioxide recovered from the thermal power plant 100 is reacted with hydrogen produced by SOEC electrolysis of water to synthesize methanol, which is then further separated and purified. The resulting methanol can be sold externally or transported to areas far from the power grid, such as isolated islands, for use in fuel cell power generation.

[0058] This application provides a peak-shaving control method for thermal power plants, applicable to the thermal power plants in the methanol production systems described in any of the above embodiments. Please refer to [link / reference needed]. Figure 3 The peak-shaving control method for thermal power plants includes steps S302 to S308.

[0059] S302, in response to the downward peak adjustment command, determines the power to be adjusted.

[0060] It is understandable that the entire power system needs to maintain a power balance, meaning that power generation and power consumption need to be balanced. However, the power load in the power system frequently changes. To maintain active power balance and system frequency stability, the dispatching department needs to adjust the output of generator 112 accordingly to adapt to changes in power load. The dispatching department will instruct power plants to perform peak shaving by issuing peak shaving commands. Downward peak shaving commands are used to instruct the combined heat and power plant to reduce the output of generator 112. The power to be adjusted is the amount of power that the combined heat and power plant needs to reduce.

[0061] S304, determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system.

[0062] It is understood that the maximum absorption capacity of the SOEC hydrogen production system refers to its maximum power. Since frequent start-ups and shutdowns of generator set 112 would reduce its lifespan, this embodiment aims to maintain the output of generator set 112 as constant as possible. The power to be adjusted is equivalent to the extra electricity generated by the thermal power plant, which can be directly absorbed by the SOEC hydrogen production system. The main cost of the SOEC hydrogen production system is concentrated in electricity prices, and the periods requiring peak shaving generally fall during periods of low electricity prices. Activating the SOEC hydrogen production system at these times can assist in peak shaving and also achieve better economic efficiency.

[0063] S306, if so, reduce the output of the thermal power plant generator 112 according to the portion of the power to be adjusted that exceeds the maximum absorption capacity, and supply power to the SOEC hydrogen production system according to the maximum absorption capacity.

[0064] When the power demand exceeds the maximum absorption capacity of the SOEC hydrogen production system, it means that the SOEC hydrogen production system cannot fully absorb the excess electricity and still needs to adjust by reducing output. However, the deeper the peak shaving depth of generator 112, the greater the harm to generator 112. At this time, the maximum absorption capacity of the SOEC hydrogen production system can be utilized to minimize the peak shaving depth of the thermal power plant and reduce the harm to generator 112.

[0065] S308, if not, then supply power to the SOEC hydrogen production system according to the power to be adjusted.

[0066] When the power to be adjusted does not exceed the maximum absorption capacity of the SOEC hydrogen production system, it means that the SOEC hydrogen production system can completely absorb the excess power, keep the output of generator set 112 unchanged, reduce the frequency of generator set 112 participating in peak shaving, and effectively extend the service life of generator set 112.

[0067] This application provides a peak-shaving control device for a thermal power plant, applicable to the methanol production system of any of the above embodiments. Please refer to [link to relevant documentation]. Figure 4 The peak-shaving control device for thermal power plants includes an instruction response module 410, a judgment module 420, a first control module 430, and a second control module 440.

[0068] The instruction response module 410 responds to the downward peak adjustment instruction and determines the power to be adjusted.

[0069] The judgment module 420 is used to determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system.

[0070] The first control module 430 is used to reduce the output of the thermal power plant generator 112 according to the portion of the power exceeding the maximum absorption capacity when it is determined that the power to be adjusted exceeds the maximum absorption capacity, and to supply power to the SOEC hydrogen production system according to the maximum absorption capacity.

[0071] The second control module 440 is used to supply power to the SOEC hydrogen production system according to the power to be adjusted when it is determined that the power to be adjusted does not exceed the maximum absorption capacity.

[0072] Specific limitations regarding the peak-shaving control device for thermal power plants can be found in the limitations of the peak-shaving control method for thermal power plants mentioned above, and will not be repeated here. Each module in the aforementioned peak-shaving control device for thermal power plants can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module. It should be noted that the module division in this embodiment is illustrative and only represents a logical functional division; other division methods may be used in actual implementation.

[0073] This application provides a computer device including one or more processors and a memory storing computer-readable instructions. When executed by one or more processors, the computer-readable instructions perform the following: in response to a down-shaving instruction, determine the power to be adjusted; determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system; if so, reduce the output of the thermal power plant generator 112 based on the portion of the power to be adjusted that exceeds the maximum absorption capacity, and supply power to the SOEC hydrogen production system based on the maximum absorption capacity; if not, supply power to the SOEC hydrogen production system based on the power to be adjusted.

[0074] Indicatively, such as Figure 5 As shown, Figure 5 This is a schematic diagram of the internal structure of a computer device provided in an embodiment of this application. (Refer to...) Figure 5 The computer device 500 includes a processing component 502, which further includes one or more processors, and memory resources represented by memory 501 for storing instructions, such as application programs, that can be executed by the processing component 502. The application programs stored in memory 501 may include one or more modules, each corresponding to a set of instructions. Furthermore, the processing component 502 is configured to execute instructions to perform the steps of the power plant peak-shaving control method of any of the above embodiments.

[0075] The computer device 500 may also include a power supply component 503 configured to perform power management of the computer device 500, a wired or wireless network interface 504 configured to connect the computer device 500 to a network, and an input / output (I / O) interface 505. The computer device 500 may operate on an operating system stored in memory 501, such as Windows Server™, Mac OS X™, Unix™, Linux™, Free BSD™, or similar.

[0076] Those skilled in the art will understand that Figure 5 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0077] This application provides a storage medium storing computer-readable instructions. When executed by one or more processors, the computer-readable instructions cause the one or more processors to perform the following actions in response to a downscaling instruction: determining the power to be adjusted; determining whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system; if so, reducing the output of the thermal power plant generator 112 based on the portion of the power to be adjusted exceeding the maximum absorption capacity, and supplying power to the SOEC hydrogen production system based on the maximum absorption capacity; if not, supplying power to the SOEC hydrogen production system based on the power to be adjusted.

[0078] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0079] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0080] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A methanol preparation system, characterized in that, It includes a thermal power plant, an SOEC hydrogen production system, a methanol synthesis system, a first heat exchanger, a second heat exchanger, and a gas separation unit; The steam pipeline of the thermal power plant is connected to the first heat exchange end of the first heat exchanger, and the second heat exchange end of the first heat exchanger is connected to the SOEC hydrogen production system, so as to output the waste heat generated by steam condensation to the SOEC hydrogen production system. The combustion exhaust gas pipeline of the thermal power plant is connected to the gas separation device, which is used to separate carbon dioxide and other gases from the combustion exhaust gas, and uses the separated carbon dioxide as a raw material for methanol synthesis in the methanol synthesis system. The first heat exchange end of the second heat exchanger is located between the combustion exhaust gas pipeline and the gas separation device, and the second heat exchange end of the second heat exchanger is connected to the SOEC hydrogen production system to output the cooling waste heat of the combustion exhaust gas to the SOEC hydrogen production system. The SOEC hydrogen production system is used to produce hydrogen gas, and the produced hydrogen gas is used as a raw material for methanol synthesis in the methanol synthesis system. The SOEC hydrogen production system also includes an auxiliary heating device, which is used to heat the SOEC hydrogen production system when the waste heat provided by the thermal power plant through the first heat exchanger and the second heat exchanger is insufficient to raise the operating temperature of the SOEC hydrogen production system to the target temperature range.

2. The methanol preparation system according to claim 1, characterized in that, The SOEC hydrogen production system is powered by the thermal power plant.

3. The methanol preparation system according to claim 1, characterized in that, The methanol preparation system also includes a dust collector, which is installed before the gas separation device and is used to remove dust from the combustion exhaust gas before it enters the gas separation device.

4. The methanol preparation system according to claim 1, characterized in that, The SOEC hydrogen production system includes an SOEC hydrogen production reactor, an oxygen purification unit, a hydrogen purification unit, an oxygen compression unit, a hydrogen compression unit, an oxygen storage tank, and a hydrogen storage tank. The SOEC hydrogen production reactor is connected to the oxygen purification device and the hydrogen purification device respectively, and is used to electrolyze water to generate hydrogen and oxygen. The hydrogen purification device is connected to the hydrogen compression device and is used to purify hydrogen and output the purified hydrogen to the hydrogen compression device. The hydrogen compression device is connected to the hydrogen storage tank and is used to compress hydrogen and store it in the hydrogen storage tank. The oxygen purification device is connected to the oxygen compression device and is used to purify oxygen and output the purified oxygen to the oxygen compression device. The oxygen compression device is connected to the oxygen storage tank and is used to compress oxygen and store it in the oxygen storage tank.

5. The methanol preparation system according to claim 1, characterized in that, The methanol production system also includes a carbon dioxide compression device and a carbon dioxide storage tank; The carbon dioxide compression device is connected to the gas separation device and the carbon dioxide storage tank respectively, and is used to compress the carbon dioxide output by the gas separation device and store it in the carbon dioxide storage tank.

6. A peak-shaving control method for a thermal power plant, characterized in that, The power plant applied to the methanol production system according to any one of claims 1-5, wherein the power plant peak-shaving control method comprises: In response to the downward peak shaving command, determine the power to be shaving; Determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system; If so, the output of the thermal power plant generator set shall be reduced according to the portion of the power to be adjusted that exceeds the maximum absorption capacity, and the SOEC hydrogen production system shall be supplied with power according to the maximum absorption capacity. If not, then power is supplied to the SOEC hydrogen production system according to the power to be adjusted.

7. A peak-shaving control device for a thermal power plant, characterized in that, A thermal power plant applied to the methanol production system according to any one of claims 1-5, wherein the thermal power plant peak-shaving control device comprises: The command response module responds to the downward peak adjustment command and determines the power to be adjusted. The judgment module is used to determine whether the power to be adjusted exceeds the maximum absorption capacity of the SOEC hydrogen production system; The first control module is used to reduce the output of the thermal power plant generator set according to the portion of the power to be adjusted that exceeds the maximum absorption capacity when it is determined that the power to be adjusted exceeds the maximum absorption capacity, and to supply power to the SOEC hydrogen production system according to the maximum absorption capacity. The second control module is used to supply power to the SOEC hydrogen production system according to the power to be adjusted when it is determined that the power to be adjusted does not exceed the maximum absorption capacity.

8. A computer device, characterized in that, It includes one or more processors and a memory storing computer-readable instructions that, when executed by the one or more processors, perform the steps of the power plant peak-shaving control method as described in claim 6.

9. A storage medium, characterized in that, The storage medium stores computer-readable instructions, which, when executed by one or more processors, cause the one or more processors to perform the steps of the power plant peak-shaving control method as described in claim 6.

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