Carbon capture system, waste incineration power generation system, and carbon capture operation method

Abstract

The application discloses a carbon capture system, a waste incineration power generation system and a carbon capture operation method. The carbon capture system comprises a first heat exchange component, a deacidification unit and a carbon capture assembly. The hot side inlet of the first heat exchange component is connected with flue gas after waste incineration. The medium water supplied by the cold side inlet of the first heat exchange component exchanges heat with the flue gas at the hot side of the first heat exchange component. The deacidification unit is connected with the hot side outlet of the first heat exchange component. The deacidification unit is connected with an absorption tower. The flue gas after deacidification by the deacidification unit enters the absorption tower to remove carbon dioxide in the flue gas. The hot side inlet of a reboiler is connected with the cold side outlet of the first heat exchange component to heat the second working medium entering a desorption tower from the absorption tower. The carbon capture system can realize recycling of flue gas waste heat, reduce external supply of energy in the carbon capture system, and also performs cooling and deacidification treatment on the flue gas.

Description

Technical Field

[0001] This invention belongs to the field of carbon capture technology, specifically relating to a carbon capture system, a waste-to-energy incineration system, and a carbon capture operation method. Background Technology

[0002] The process of municipal solid waste incineration for power generation in my country is a source of greenhouse gas emissions, with net carbon dioxide emissions of 166-212 kg per ton of waste. To further enhance the negative carbon emission attributes of waste incineration power generation, carbon capture devices should be added to further remove carbon dioxide from the flue gas.

[0003] In related technologies, some thermal power units are equipped with carbon capture systems. However, since the flue gas composition of waste incineration power plants is different from that of conventional coal-fired power plants, containing hydrogen chloride gas which has a certain degree of corrosiveness, the flue gas pretreatment unit in traditional carbon capture devices cannot be used directly. If the high-temperature flue gas (generally above 220 degrees Celsius) emitted from the waste incineration boiler is directly deacidified, the heat of this part of the flue gas will be wasted. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, embodiments of the present invention propose a carbon capture system that can recover and utilize waste heat from flue gas, reduce the external energy supply to the carbon capture system, and also cool and deacidify the flue gas.

[0006] Embodiments of the present invention also propose a waste incineration power generation system.

[0007] The embodiments of the present invention further propose a carbon capture operation method applicable to waste incineration power plants.

[0008] A carbon capture system according to an embodiment of the present invention includes:

[0009] The first heat exchange component has a hot-side inlet connected to the flue gas after waste incineration. The medium water supplied by the cold-side inlet of the first heat exchange component exchanges heat with the flue gas on the hot side of the first heat exchange component to form superheated steam at the cold-side outlet of the first heat exchange component.

[0010] A deacidification unit is connected to the hot-side outlet of the first heat exchange component to deacidify the cooled flue gas.

[0011] A carbon capture assembly, comprising an absorption tower, a desorption tower, and a second heat exchange component, wherein the second heat exchange component is connected between the absorption tower and the desorption tower, and is used to exchange heat between a first working medium entering the absorption tower from the desorption tower and a second working medium entering the desorption tower from the absorption tower.

[0012] The deacidification unit is connected to the absorption tower. The flue gas after deacidification by the deacidification unit enters the absorption tower to remove carbon dioxide from the flue gas. The clean flue gas is discharged through the flue gas outlet of the absorption tower.

[0013] The hot-side inlet of the reboiler in the desorption tower is connected to the cold-side outlet of the first heat exchange component to heat the second working medium entering the desorption tower from the absorption tower.

[0014] The carbon capture system of this invention can recover and utilize waste heat from flue gas, reduce the external energy supply to the carbon capture system, cool and deacidify the flue gas, balance energy utilization and conversion in the carbon capture system, improve the system balance of the carbon capture system, and improve the carbon dioxide capture effect in the flue gas.

[0015] In some embodiments, the hot-side outlet of the reboiler is connected to the cold-side inlet of the first heat exchange component, so that the medium water at the hot-side outlet of the reboiler flows back into the first heat exchange component.

[0016] In some embodiments, a third heat exchange component is further included, wherein the hot-side inlet of the third heat exchange component is connected to the cold-side outlet of the first heat exchange component, and the cold-side inlet of the third heat exchange component is connected to the flue gas outlet of the absorption tower, so that the clean flue gas discharged from the absorption tower exchanges heat with the superheated steam entering the third heat exchange component.

[0017] In some embodiments, the hot-side outlet of the third heat exchange component is connected to the cold-side inlet of the first heat exchange component, so that the medium water at the hot-side outlet of the third heat exchange component flows back into the first heat exchange component.

[0018] In some embodiments, a first valve is provided between the cold-side outlet of the first heat exchange component and the hot-side inlet of the reboiler, and a second valve is provided between the cold-side outlet of the first heat exchange component and the hot-side inlet of the third heat exchange component.

[0019] In some embodiments, the deacidification unit includes a tank and a first pump, the first pump being used to pump seawater into the tank so that the seawater and flue gas come into contact and react in the tank.

[0020] A waste-to-energy incineration system according to an embodiment of the present invention includes an incineration generator set and a carbon capture system as described in any of the foregoing embodiments; the incineration generator set includes:

[0021] Incinerator;

[0022] A boiler, which is connected to the incinerator, is used to heat the medium water inside the boiler and generate steam. The flue gas outlet of the boiler is connected to the hot side inlet of the first heat exchange component.

[0023] A steam turbine connected to the boiler to drive the steam turbine through steam generated by the boiler;

[0024] A generator, which is connected to the steam turbine, is used to drive the generator to generate electricity via the steam turbine.

[0025] In some embodiments, a solid waste treatment unit is further included, which is connected to the ash discharge port of the incinerator and the ash discharge port of the boiler.

[0026] In some embodiments, a first pipe is further included, the two ends of which are respectively connected to the extraction port of the steam turbine and the hot-side inlet of the reboiler in the desorption tower, and a third valve is provided on the first pipe; and / or

[0027] It also includes a second pipe, the two ends of which are connected to the hot side inlet of a third heat exchange component that is connected to the steam extraction port of the steam turbine and the flue gas outlet of the absorption tower, respectively. A fourth valve is provided on the second pipe.

[0028] The carbon capture operation method for waste-to-energy plants according to embodiments of the present invention, used for carbon capture of flue gas in the waste-to-energy system described in any of the above embodiments, specifically includes the following steps:

[0029] Based on the flue gas flow rate and flue gas temperature at the boiler's flue gas outlet, the flow rate and temperature of superheated steam at the cold side outlet of the first heat exchange component are obtained.

[0030] The cold-side outlet of the first heat exchange component is connected to the reboiler in the desorption tower and the third heat exchange component at the flue gas outlet in the absorption tower, and the initial flow rate ratio of superheated steam delivered from the cold-side outlet of the first heat exchange component to the reboiler and the third heat exchange component is determined.

[0031] The temperature T1 of the second working medium entering the desorption tower and the flue gas temperature T2 of the cold side outlet of the third heat exchange component are obtained.

[0032] Determine whether temperature T1 is greater than the first threshold.

[0033] If not, the steam from the turbine is extracted and delivered to the reboiler, or / and the flow rate of superheated steam delivered to the reboiler from the cold side outlet of the first heat exchange component is increased so that the temperature of the second working medium entering the desorption tower is greater than the first threshold.

[0034] Determine whether temperature T2 is greater than the second threshold.

[0035] If not, the steam from the turbine is extracted and delivered to the third heat exchange component so that the flue gas temperature at the cold side outlet of the third heat exchange component is greater than the second threshold. Attached Figure Description

[0036] Figure 1 This is a system diagram of the carbon capture system and the incineration generator set according to an embodiment of the present invention.

[0037] Figure 2 This is a process flow diagram of a carbon capture operation method applicable to waste incineration power plants according to an embodiment of the present invention.

[0038] Figure label:

[0039] 101. Incinerator; 102. Boiler; 103. Steam turbine; 104. Generator; 105. Solid waste treatment unit;

[0040] 200. First heat exchange component;

[0041] 300. Deacidification Unit;

[0042] 400. Absorption tower;

[0043] 500. Desorption tower; 501. Reboiler; 502. First valve;

[0044] 600. Second heat exchange component;

[0045] 700, Third heat exchange component; 701, Second valve;

[0046] 801, First pipe; 802, Second pipe; 803, Third valve; 804, Fourth valve. Detailed Implementation

[0047] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0048] See Figure 1As shown, the carbon capture system according to an embodiment of the present invention includes a first heat exchange component 200, a deacidification unit 300, and a carbon capture assembly. The hot-side inlet of the first heat exchange component 200 is connected to the flue gas after waste incineration. The medium water supplied by the cold-side inlet of the first heat exchange component 200 exchanges heat with the flue gas on the hot side of the first heat exchange component 200 to form superheated steam at the cold-side outlet of the first heat exchange component 200. It should be understood that after the high-temperature flue gas after waste incineration passes through the first heat exchange component 200, it indirectly exchanges heat with the medium water supplied into the first heat exchange component 200, thereby allowing the first heat exchange component 200 to output low-temperature flue gas and superheated steam. The low-temperature flue gas is convenient for subsequent deacidification treatment and carbon capture, and the superheated steam can maintain the energy balance of the carbon capture system during carbon capture, achieving energy self-sufficiency and reducing the introduction of external energy.

[0049] The deacidification unit 300 is connected to the hot-side outlet of the first heat exchange component 200 to deacidify the cooled flue gas. The carbon capture assembly includes an absorption tower 400, a desorption tower 500, and a second heat exchange component 600. The second heat exchange component 600 is connected between the absorption tower 400 and the desorption tower 500. The second heat exchange component 600 is used to exchange heat between the first working medium entering the absorption tower 400 from the desorption tower 500 and the second working medium entering the desorption tower 500 from the absorption tower 400.

[0050] In other words, the flue gas, after being cooled by the first heat exchange component 200, enters the deacidification unit 300. The deacidification medium in the deacidification unit 300 comes into full contact with the flue gas and absorbs acidic gases such as hydrogen chloride and sulfides in the flue gas.

[0051] Optionally, the deacidification unit 300 can use seawater. Due to the developed industry and high population density in coastal areas, the amount of waste generated is also relatively large. In power plant units in coastal areas, the natural seawater has a pH value of about 8.0 and is alkaline. This can be used to wash away acidic gases such as hydrogen chloride and sulfides in the flue gas and release carbon dioxide. At the same time, the seawater can be used to further cool the flue gas, replacing the flue gas cooling link of the traditional carbon capture system and improving the capture effect of the flue gas in the absorption tower 400.

[0052] By using continuously flowing and relatively stable natural seawater for cooling and deacidification, the temperature of the flue gas entering the absorption tower at 400°C can be kept stable, which facilitates the improvement of carbon capture efficiency and maintains the balance and stability of the system.

[0053] It should be noted that the first working medium is lean solution, and the second working medium is rich solution. The flue gas containing carbon dioxide gas introduced into the absorption tower 400 reacts with the lean solution introduced into the absorption tower 400. The lean solution absorbs the carbon dioxide gas to form rich solution. The clean flue gas with the absorbed carbon dioxide is discharged from the top of the absorption tower 400. The rich solution located at the bottom of the absorption tower 400 is transported to the desorption tower 500. After entering the desorption tower 500, the rich solution is heated by the reboiler 501 and desorbs the carbon dioxide gas to form lean solution. The desorbed carbon dioxide gas is discharged from the carbon dioxide outlet at the top of the desorption tower 500. The solutions in the absorption tower 400 and the desorption tower 500 are circulated through the second heat exchange component 600. The lean solution and the rich solution exchange heat in the second heat exchange component 600 to improve the heat utilization rate and maintain system balance.

[0054] The carbon dioxide desorbed in the desorption tower 500 is discharged from the carbon dioxide outlet at the top of the desorption tower 500 and then undergoes centralized treatment and application through the carbon capture and treatment unit.

[0055] In this embodiment of the invention, the deacidification unit 300 is connected to the absorption tower 400. The flue gas after deacidification by the deacidification unit 300 enters the absorption tower 400 to remove carbon dioxide from the flue gas. The clean flue gas is discharged through the flue gas outlet of the absorption tower 400. It should be understood that the high-temperature flue gas after waste incineration is cooled by the first heat exchange component 200 and then enters the deacidification unit 300 for deacidification and secondary cooling. Finally, it enters the absorption tower 400 to react with the lean liquor, thereby capturing carbon dioxide in the flue gas.

[0056] The hot-side inlet of the reboiler 501 in the desorption tower 500 is connected to the cold-side outlet of the first heat exchange component 200 to heat the second working medium entering the desorption tower 500 from the absorption tower 400. In this embodiment of the invention, the reboiler 501 is used to heat the rich liquid pumped into the desorption tower 500 from the absorption tower 400. Since the rich liquid has already exchanged heat with the lean liquid pumped into the absorption tower 400 from the desorption tower 500 through the second heat exchange component 600 before entering the reboiler 501, the rich liquid desorbs carbon dioxide in the desorption tower 500 after being heated a second time in the reboiler 501.

[0057] In the reboiler 501, superheated steam output from the first heat exchange component 200 is used as a heat source to reheat the rich liquid, thus realizing the collection and utilization of waste heat from the flue gas. This embodiment of the invention collects waste heat from the flue gas in two ways: firstly, it cools the flue gas, ensuring the effective collection of carbon dioxide in the absorption tower 400; secondly, it heats the rich liquid after carbon dioxide absorption, ensuring the desorption of carbon dioxide from the rich liquid in the desorption tower 500. This results in high energy utilization and energy savings for the carbon capture system.

[0058] The carbon capture system of this invention can recover and utilize waste heat from flue gas, reduce the external energy supply to the carbon capture system, cool and deacidify the flue gas, balance energy utilization and conversion in the carbon capture system, improve the system balance of the carbon capture system, and improve the carbon dioxide capture effect in the flue gas.

[0059] In some embodiments, the hot-side outlet of the reboiler 501 is connected to the cold-side inlet of the first heat exchange component 200, so that the medium water at the hot-side outlet of the reboiler 501 flows back into the first heat exchange component 200. It should be understood that a circulation loop is formed between the cold side of the first heat exchange component 200 and the hot side of the reboiler 501, thereby ensuring the internal recycling of the medium water, reducing the amount of water made up in the system, and improving the reuse of the waste heat of the condensate at the hot-side outlet of the reboiler 501.

[0060] In some embodiments, the carbon capture system further includes a third heat exchange component 700, the hot side inlet of the third heat exchange component 700 being connected to the cold side outlet of the first heat exchange component 200, and the cold side inlet of the third heat exchange component 700 being connected to the flue gas outlet of the absorption tower 400, so that the clean flue gas discharged from the absorption tower 400 exchanges heat with the superheated steam entering the third heat exchange component 700.

[0061] The temperature of the clean flue gas discharged from the absorption tower 400 is relatively low. If it is discharged directly, it will not be conducive to the diffusion of the flue gas plume. In this embodiment of the invention, by setting a third heat exchange component 700, part of the superheated steam discharged from the first heat exchange component 200 can be transported into the third heat exchange component 700, and then exchanged with the clean flue gas discharged from the absorption tower 400 in the third heat exchange component 700 to increase the temperature of the clean flue gas, thereby increasing the flue gas plume diffusion height.

[0062] In some embodiments, the hot-side outlet of the third heat exchange component 700 is connected to the cold-side inlet of the first heat exchange component 200, so that the medium water at the hot-side outlet of the third heat exchange component 700 flows back into the first heat exchange component 200. A circulation loop is formed between the cold side of the first heat exchange component 200 and the hot side of the third heat exchange component 700, thereby ensuring the internal recycling of the medium water, reducing the amount of water made up in the system, and improving the reuse of waste heat from the condensate at the hot-side outlet of the third heat exchange component 700.

[0063] Optionally, in this embodiment of the invention, a water supply port is provided at the cold side inlet of the first heat exchange component 200. The water supply port can be used to replenish the medium water in the circulation loop composed of the first heat exchange component 200, the third heat exchange component 700 and the reboiler 501.

[0064] In this embodiment of the invention, the first heat exchange component 200 is a gas-liquid heat exchanger, the second heat exchange component 600 is a liquid-liquid heat exchanger, and the third heat exchange component 700 is a gas-gas heat exchanger.

[0065] In some embodiments, a first valve 502 is provided between the cold-side outlet of the first heat exchange component 200 and the hot-side inlet of the reboiler 501, and a second valve 701 is provided between the cold-side outlet of the first heat exchange component 200 and the hot-side inlet of the third heat exchange component. By providing the first valve 502 and the second valve 701, the on / off state and flow rate ratio of the pipes delivering superheated steam to the reboiler 501 and the third heat exchange component can be adjusted, thereby achieving better energy distribution and utilization.

[0066] When the flow rate and temperature of the flue gas from waste incineration flue gas flue, the energy of the superheated steam is prone to fluctuation. In order to ensure the stable and orderly operation of the carbon capture system, the flow rate of the superheated steam can be reasonably allocated based on the first valve 502 and the second valve 701. Under the premise that the reboiler 501 can effectively heat the rich liquid to the preset temperature, the clean flue gas discharged from the absorption tower 400 is heated to increase the plume diffusion height of the clean flue gas.

[0067] In some embodiments, the deacidification unit 300 includes a tank and a first pump body, the first pump body being used to pump seawater into the tank body to allow the seawater to contact and react with the flue gas within the tank body. It should be understood that the deacidification unit 300 utilizes seawater for cooling and deacidifying the flue gas; therefore, sufficient contact between the flue gas and seawater is required.

[0068] Optionally, by setting up a tank and arranging a packing layer inside the tank, a first pump is used to pump natural seawater into the top of the tank and spray it from top to bottom. After the flue gas enters the tank, it flows from bottom to top. The flue gas and seawater can fully contact and react when passing through the packing layer, thereby achieving deacidification and cooling.

[0069] The present invention utilizes seawater for desulfurization and cooling, which can reduce the cost of desulfurization, reduce the fluctuation range of flue gas temperature entering the absorption tower 400, and improve the stability of the system.

[0070] In this embodiment of the invention, the temperature of the high-temperature flue gas at the hot side inlet of the first heat exchange component 200 is around 220 degrees Celsius, the temperature of the flue gas at the hot side outlet of the first heat exchange component 200 is around 40 degrees Celsius, for example, 35 degrees Celsius to 45 degrees Celsius, the temperature of the medium water at the cold side inlet of the first heat exchange component 200 is around 25 degrees Celsius, for example, using demineralized water at room temperature, and the temperature of the superheated steam at the cold side outlet of the first heat exchange component 200 is around 130 degrees Celsius, for example, the temperature of the superheated steam is 120 degrees Celsius to 145 degrees Celsius.

[0071] The temperature at the hot side inlet of reboiler 501 is roughly the same as the temperature of the superheated steam. The temperature of the rich liquid at the cold side inlet of reboiler 501 is around 70 degrees Celsius, and the temperature of the rich liquid at the cold side outlet of reboiler 501 rises to around 110 degrees Celsius. For example, the temperature of the rich liquid at the cold side outlet of reboiler 501 is between 110 and 120 degrees Celsius.

[0072] The temperature of the clean flue gas discharged from the absorption tower 400 is around 40 degrees Celsius. In order to increase the flue gas plume diffusion height, the temperature of the clean flue gas can be increased to 60 to 110 degrees Celsius by exchanging heat with some superheated steam.

[0073] According to an embodiment of the present invention, a waste incineration power generation system includes a set of incineration generators 104 and a carbon capture system as described in any of the above embodiments. The set of incineration generators 104 includes an incinerator 101, a boiler 102, a steam turbine 103, and a generator 104. The boiler 102 is connected to the incinerator 101 to heat the medium water inside the boiler 102 and generate steam. The flue gas outlet of the boiler 102 is connected to the hot side inlet of the first heat exchange component 200. The steam turbine 103 is connected to the boiler 102 to drive the steam turbine 103 to operate. The generator 104 is driven by the steam turbine 103 to generate electricity by driving the generator 104 through the steam turbine 103.

[0074] It should be understood that the combined use of the incineration generator set 104 and the carbon capture system enables carbon capture of flue gas, and also solves the problem in related technologies where carbon capture systems require a large amount of steam to maintain system stability. This achieves energy conservation and emission reduction, improves the utilization rate of flue gas waste heat, and reduces the carbon capture system's dependence on steam extracted from the turbine 103. The steam generated by the boiler 102 drives the turbine 103 to power the generator 104, which then generates electricity and transmits it to the grid.

[0075] This invention transforms the high-temperature characteristics of waste incineration power plant flue gas into an advantage by rationally arranging the carbon capture system, combining the flue gas cooling stage with the acid removal stage, and using the heat from the inlet flue gas to heat the carbon capture desorption tower 500, thereby reducing system heat consumption; and by using seawater for acid removal, it better treats the unique hydrogen chloride in the flue gas of incineration power plants, reducing the corrosion of the system by acidic gases.

[0076] In some embodiments, a solid waste treatment unit 105 is also included, which is connected to the slag discharge port of the incinerator 101 and the ash discharge port of the boiler 102.

[0077] The flue gas that enters boiler 102 after waste incineration, and the ash and slag that pass through the filter screen are transported to solid waste treatment unit 105 together with the residue due to gravity settling.

[0078] In some embodiments, the waste-to-energy incineration system further includes a first pipe 801, the two ends of which are connected to the extraction port of the turbine 103 and the hot-side inlet of the reboiler 501 in the desorption tower 500, respectively. A third valve 803 is provided on the first pipe 801. The first pipe 801 is connected to the hot-side inlet of the reboiler 501, and the opening and closing of the first pipe can be controlled by the third valve 803. Thus, when the superheated steam provided by the first heat exchange component 200 cannot meet the heat demand of the carbon capture system, the extraction steam from the turbine 103 can be used to heat the rich liquid in the desorption tower 500 in a timely manner, ensuring the normal operation of the carbon capture system.

[0079] Furthermore, the waste-to-energy incineration system also includes a second pipe 802, with its two ends connected to the steam extraction port of the turbine 103 and the hot-side inlet of the third heat exchange component 700, respectively. The third heat exchange component 700 is connected to the flue gas outlet of the absorption tower 400. A fourth valve 804 is installed on the second pipe 802. The second pipe 802 is connected to the hot-side inlet of the third heat exchange component 700, and the opening and closing of the second pipe can be controlled by the third valve 803. Thus, when the superheated steam provided by the first heat exchange component 200 cannot meet the heat demand of the carbon capture system, and it is necessary to increase the plume diffusion height of the clean flue gas discharged from the absorption tower 400, the steam extraction from the turbine 103 can be used to heat the clean flue gas in a timely manner.

[0080] This invention utilizes the heat from the high-temperature flue gas of the incinerator boiler 102 to achieve cross-heat exchange between the high-temperature flue gas and demineralized water / cooling water through a heat exchange unit. The superheated steam can provide a stable heat source for heating the desorption tower 500 in the subsequent carbon capture system, eliminating the need to extract steam from the power plant to heat the desorption tower 500 or reduce the power plant's steam extraction. A seawater deacidification unit 300 is used, taking advantage of the alkaline nature of natural seawater (pH approximately 8.0) to wash away hydrogen chloride and sulfides from the flue gas, releasing carbon dioxide. Simultaneously, the seawater further cools the flue gas, replacing the flue gas cooling stage in related technologies for carbon capture systems.

[0081] See Figure 2 As shown, the carbon capture operation method applicable to waste-to-energy plants according to embodiments of the present invention, used for carbon capture of flue gas in the waste-to-energy system of any of the above embodiments, specifically includes the following steps:

[0082] S101. Based on the flue gas flow rate and temperature at the boiler's flue gas outlet, obtain the flow rate and temperature of superheated steam at the cold side outlet of the first heat exchange component. When the flue gas flow rate and temperature fluctuate during waste incineration, it can easily lead to insufficient superheated steam flow rate output by the first heat exchange component, which cannot meet the needs of the carbon capture system. Therefore, by obtaining the flow rate and temperature of superheated steam in a timely manner, it is convenient to adjust and control the balance of the system.

[0083] S102. Connect the cold-side outlet of the first heat exchange component to the third heat exchange component at the reboiler in the desorption tower and the flue gas outlet in the absorption tower, and determine the initial flow rate ratio of the superheated steam supplied from the cold-side outlet of the first heat exchange component to the reboiler and the third heat exchange component. Since the temperature in the reboiler and the absorption tower is relatively stable, the initial flow rate ratio of the superheated steam can be reasonably controlled under the premise of ensuring that the flow rate and temperature of the superheated steam supplied to the reboiler are constant.

[0084] S103. Obtain the temperature T1 of the second working medium entering the desorption tower and the flue gas temperature T2 of the cold side outlet of the third heat exchange component; by detecting the temperature of the second working medium and the flue gas discharged from the cold side outlet of the third heat exchange component in the desorption tower, the carbon capture effect and the clean flue gas plume diffusion effect in the carbon capture system can be detected.

[0085] S104. Determine whether the temperature T1 is greater than the first threshold.

[0086] S105. If not, then extract steam from the turbine and distribute it to the reboiler, or / and increase the flow rate of superheated steam supplied to the reboiler from the cold side outlet of the first heat exchange component, so that the temperature of the second working medium entering the desorption tower is greater than the first threshold. When the temperature T1 is not greater than the first threshold, the balance of the carbon capture system is affected, and it is necessary to adjust the energy input on the hot side of the reboiler to ensure the system balance. Therefore, the normal and stable operation of the desorption tower and the absorption tower can be ensured by extracting steam from the turbine and distributing it to the reboiler, or by increasing the flow rate of superheated steam supplied to the reboiler from the cold side outlet of the first heat exchange component.

[0087] S106. Determine whether the temperature T2 is greater than the second threshold.

[0088] S107. If not, steam from the turbine is extracted and distributed to the third heat exchanger to ensure that the flue gas temperature at the cold side outlet of the third heat exchanger is greater than the second threshold. If the temperature T2 is not greater than the second threshold, the plume diffusion effect of the clean flue gas is not ideal. The magnitude of the second threshold is determined based on the impact of the clean flue gas emissions on the surrounding environment.

[0089] If the quality of the steam extracted by the turbine is higher than that of the superheated steam in the first heat exchange component, then when temperature T1 fails to meet the first threshold and temperature T2 fails to meet the second threshold, the turbine steam is preferentially extracted and supplied to the reboiler. The proportion of superheated steam supplied to the reboiler from the first heat exchange component is then reduced. The low-quality steam is used to enter the third heat exchange component, and the high-quality steam is used to enter the reboiler, while ensuring that both temperature T1 and temperature T2 meet the requirements.

[0090] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A carbon capture system, characterized in that, include: The first heat exchange component has a hot-side inlet connected to the flue gas after waste incineration. The medium water supplied by the cold-side inlet of the first heat exchange component exchanges heat with the flue gas on the hot side of the first heat exchange component to form superheated steam at the cold-side outlet of the first heat exchange component. A deacidification unit is connected to the hot-side outlet of the first heat exchange component to deacidify the cooled flue gas. A carbon capture assembly, comprising an absorption tower, a desorption tower, and a second heat exchange component, wherein the second heat exchange component is connected between the absorption tower and the desorption tower, and is used to exchange heat between a first working medium entering the absorption tower from the desorption tower and a second working medium entering the desorption tower from the absorption tower. The deacidification unit is connected to the absorption tower. The flue gas after deacidification by the deacidification unit enters the absorption tower to remove carbon dioxide from the flue gas. The clean flue gas is discharged through the flue gas outlet of the absorption tower. The hot-side inlet of the reboiler in the desorption tower is connected to the cold-side outlet of the first heat exchange component to heat the second working medium entering the desorption tower from the absorption tower. It also includes a third heat exchange component, the hot side inlet of which is connected to the cold side outlet of the first heat exchange component, and the cold side inlet of the third heat exchange component is connected to the flue gas outlet of the absorption tower, so that the clean flue gas discharged from the absorption tower exchanges heat with the superheated steam entering the third heat exchange component. A first valve is provided between the cold side outlet of the first heat exchange component and the hot side inlet of the reboiler, and a second valve is provided between the cold side outlet of the first heat exchange component and the hot side inlet of the third heat exchange component. By setting the first valve and the second valve, the on / off state and flow rate ratio of the pipes for superheated steam to be delivered to the reboiler and the third heat exchange component can be adjusted to realize the distribution and utilization of energy. The deacidification unit includes a tank and a first pump body, the first pump body being used to pump seawater into the tank body so that the seawater and flue gas can come into contact and react in the tank body.

2. The carbon capture system according to claim 1, characterized in that, The hot-side outlet of the reboiler is connected to the cold-side inlet of the first heat exchange component, so that the medium water at the hot-side outlet of the reboiler flows back into the first heat exchange component.

3. The carbon capture system according to claim 1, characterized in that, The hot-side outlet of the third heat exchange component is connected to the cold-side inlet of the first heat exchange component so that the medium water at the hot-side outlet of the third heat exchange component flows back into the first heat exchange component.

4. A waste-to-energy incineration system, characterized in that, Includes a waste incineration power generation unit and a carbon capture system as described in any one of claims 1-3; the waste incineration power generation unit includes: Incinerator; A boiler, which is connected to the incinerator, is used to heat the medium water inside the boiler and generate steam. The flue gas outlet of the boiler is connected to the hot side inlet of the first heat exchange component. A steam turbine connected to the boiler to drive the steam turbine through steam generated by the boiler; A generator, which is connected to the steam turbine, is used to drive the generator to generate electricity via the steam turbine.

5. The waste-to-energy incineration system according to claim 4, characterized in that, It also includes a solid waste treatment unit, which is connected to the slag discharge port of the incinerator and the ash discharge port of the boiler.

6. The waste-to-energy incineration system according to claim 4, characterized in that, It also includes a first pipe, the two ends of which are connected to the steam extraction port of the steam turbine and the hot-side inlet of the reboiler in the desorption tower, respectively, and a third valve is provided on the first pipe; and / or It also includes a second pipe, the two ends of which are connected to the hot side inlet of a third heat exchange component that is connected to the steam extraction port of the steam turbine and the flue gas outlet of the absorption tower, respectively. A fourth valve is provided on the second pipe.

7. A carbon capture operation method suitable for waste incineration power plants, characterized in that, Carbon capture of flue gas in the waste incineration power generation system according to any one of claims 4-6 specifically includes the following steps: Based on the flue gas flow rate and flue gas temperature at the boiler's flue gas outlet, the flow rate and temperature of superheated steam at the cold side outlet of the first heat exchange component are obtained. The cold-side outlet of the first heat exchange component is connected to the reboiler in the desorption tower and the third heat exchange component at the flue gas outlet in the absorption tower, and the initial flow rate ratio of superheated steam delivered from the cold-side outlet of the first heat exchange component to the reboiler and the third heat exchange component is determined. Obtain the temperature of the second working medium entering the desorption tower. and the flue gas temperature at the cold side outlet of the third heat exchange component ; Determine temperature Is it greater than the first threshold? If not, the steam from the turbine is extracted and delivered to the reboiler, or / and the flow rate of superheated steam delivered to the reboiler from the cold side outlet of the first heat exchange component is increased so that the temperature of the second working medium entering the desorption tower is greater than the first threshold. Determine temperature Is it greater than the second threshold? If not, the steam from the turbine is extracted and delivered to the third heat exchange component so that the flue gas temperature at the cold side outlet of the third heat exchange component is greater than the second threshold.

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