Rich amine liquid vaporization heat exchanger, amine liquid recovery system and carbon dioxide capture device

Abstract

The application provides an amine-rich liquid vaporization heat exchanger, an amine liquid recovery system and a carbon dioxide capturing device. An inner wall surface of a cold fluid flow channel of the amine-rich liquid vaporization heat exchanger is coated with a coating layer; the coating layer comprises a base material capable of realizing carbon dioxide bubble nucleation and an active catalytic component loaded on the base material and capable of reducing the carbon dioxide desorption reaction activation energy of the amine-rich liquid. The amine-rich liquid vaporization heat exchanger is provided with a specific coating layer, so that the amine-rich liquid can realize efficient carbon dioxide desorption by fully utilizing the heat energy of the hot fluid. The amine liquid recovery system is provided with a first-stage lean and rich amine liquid heat exchanger, a first-stage shunt device, a second-stage lean and rich amine liquid heat exchanger, a second-stage shunt device, an amine-rich liquid vaporization heat exchanger, a gas-liquid separation device and a desorption tower. The amine liquid recovery system realizes the effective guarantee of the phase stability in the system and the full utilization of waste heat resources to reduce energy by means of multi-stage heat exchange, multi-stage shunting, heat exchange desorption and gas-liquid separation.

Description

Technical Field

[0001] This invention belongs to the field of carbon dioxide capture technology, specifically relating to an amine-rich liquid vaporization heat exchanger, an amine liquid recovery system and method, and a carbon dioxide capture device and method. Background Technology

[0003] Carbon dioxide capture, utilization and storage (CCUS) is a greenhouse gas emission reduction technology suitable for large-scale industrial application. It is not only an important technical means for the low-carbon utilization of fossil energy, but also an important technical means for maintaining the flexibility of the power system. It is also a feasible technical means for the deep decarbonization of industries that are difficult to reduce emissions, such as steel and cement. It is gradually becoming an indispensable technical component for reducing carbon emissions to cope with climate change.

[0004] Currently, mainstream carbon dioxide capture technologies include chemical absorption, physical absorption, and adsorption. Among these, chemical absorption is a mature technology, well-suited for capturing low to medium concentrations of carbon dioxide, and accounts for over 65% of the total carbon dioxide capture market share. Within chemical absorption carbon dioxide capture technologies, the organic amine method, which utilizes organic amine solutions to absorb carbon dioxide, has become one of the main carbon dioxide capture technologies suitable for large-scale industrial applications. However, the high energy consumption of the organic amine method limits its development speed. Therefore, research on energy saving and consumption reduction in the organic amine method has always been a key focus for industry professionals.

[0005] In organic amine-based carbon dioxide capture technology, the energy consumption for desorption and regeneration of the amine-rich solution after carbon dioxide absorption accounts for approximately 60% of the total capture energy consumption. Effectively reducing regeneration energy consumption is a major research task for the present and future. Utilizing waste heat resources is one of the main pathways to reduce energy consumption, but the carbon capture field requires high temperatures for waste heat resources, generally above 120℃. Traditional organic amine solutions have high desorption temperatures, and amine-rich solutions struggle to reach their vaporization point at low temperatures. With the development of carbon capture technology, high-efficiency composite amine solutions with low desorption temperatures have emerged. However, although these high-efficiency composite amine solutions have significantly lower desorption temperatures, problems such as poor heat exchange, limited energy reduction, and abnormal equipment operation often arise when utilizing waste heat resources to reduce energy consumption during the desorption process.

[0006] In summary, there is still a need to research new processes for amine recovery in high-efficiency composite amine carbon dioxide capture technology, which can make full use of waste heat resources to reduce energy consumption and effectively ensure the normal operation of the equipment. Summary of the Invention

[0007] The purpose of this invention is to provide a technical solution that can help the amine liquid recovery process in the efficient composite amine carbon dioxide capture technology to fully utilize waste heat resources, reduce energy consumption, and effectively ensure the normal operation of the equipment.

[0008] To achieve the above objectives, the present invention provides the following five technical solutions.

[0009] In a first aspect, the present invention provides a rich amine liquid vaporization heat exchanger, wherein the inner wall surface of the cold fluid flow channel of the rich amine liquid vaporization heat exchanger is coated with a coating; the coating comprises a matrix material and an active catalytic component loaded on the matrix material; The matrix material is capable of enabling carbon dioxide bubble nucleation; The active catalytic component can reduce the activation energy of the carbon dioxide desorption reaction of the amine-rich liquid obtained after the organic amine absorbent absorbs carbon dioxide.

[0010] The amine-rich liquid vaporization heat exchanger provided by this invention has a specific coating on the inner wall surface of the cold fluid flow channel. When the amine-rich liquid obtained after the organic amine absorbs carbon dioxide is heated in this amine-rich liquid vaporization heat exchanger, on the one hand, the active catalytic component in the coating acts as a catalyst to reduce the activation energy required for the chemical desorption of carbon dioxide in the amine-rich liquid, allowing the desorption reaction to occur at a lower temperature; on the other hand, the matrix material in the coating facilitates the adhesion of initial carbon dioxide bubbles, which become nucleation sites for subsequent carbon dioxide molecule aggregation and precipitation. Utilizing this dual "catalytic-nucleation" mechanism of the coating, the desorption efficiency of carbon dioxide in the amine-rich liquid vaporization heat exchanger is greatly promoted, enabling the amine-rich liquid vaporization heat exchanger to fully utilize the thermal energy of the hot fluid to efficiently desorb carbon dioxide from the cold fluid (i.e., the amine-rich liquid). This amine-rich liquid vaporization heat exchanger exhibits highly efficient heat exchange and desorption performance.

[0011] The amine-rich liquid vaporization heat exchanger provided by this invention is well applicable to the amine liquid recovery process in the high-efficiency composite amine carbon dioxide capture technology. It can effectively help the amine liquid recovery process in the high-efficiency composite amine carbon dioxide capture technology to make full use of waste heat resources, reduce energy consumption, and effectively ensure the normal operation of the equipment.

[0012] According to a specific embodiment of the first aspect of the present invention, preferably, the matrix material is selected from porous ceramic materials and / or polymer materials; More preferably, the matrix material is selected from one or more combinations of silicon carbide foam ceramic materials, alumina foam ceramic materials, and polytetrafluoroethylene (PTFE) materials.

[0013] According to a specific embodiment of the first aspect of the present invention, preferably, the active catalytic component is selected from at least one of metal oxides and solid acids; More preferably, the active catalytic component is selected from metal oxides; More preferably, the metal oxide is selected from one or more of nano-titanium dioxide (TiO2), nano-zirconium oxide (ZrO2), and nano-aluminum oxide (Al2O3); More preferably, the solid acid is selected from one or more of HZSM-5 molecular sieves, H-Beta molecular sieves, and HY molecular sieves; For example, the active catalytic component is a mixture of nano-titanium dioxide (TiO2), nano-zirconium oxide (ZrO2), and nano-aluminum oxide (Al2O3); further, the mass ratio of nano-titanium dioxide (TiO2), nano-zirconium oxide (ZrO2), and nano-aluminum oxide (Al2O3) is 30-50:20-40:10-30.

[0014] According to a specific embodiment of the first aspect of the present invention, preferably, the surface roughness Ra of the coating is 5-50 micrometers; The rough microstructure is more conducive to the nucleation of carbon dioxide bubbles and to the contact and heat exchange between the fluid and the wall, thereby further improving the desorption efficiency.

[0015] According to a specific embodiment of the first aspect of the present invention, preferably, the content of the active catalytic component is 5-15% based on the total mass of the matrix material as 100%.

[0016] According to a specific embodiment of the first aspect of the present invention, preferably, the thickness of the coating is 50-500 micrometers.

[0017] According to a specific embodiment of the first aspect of the present invention, preferably, the coating is prepared by the following manner: The coating preparation slurry is applied to the inner wall surface of the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger, and then dried and sintered to achieve the coating on the inner wall surface of the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger. More preferably, the slurry comprises the active catalytic component, the precursor of the matrix material, a solvent, and a binder; even more preferably, the precursor of the matrix material is selected from one or more combinations of alumina micropowder, boehmite, and alumina sol; even more preferably, the solvent is selected from one or more combinations of water, ethanol, and ethylene glycol; even more preferably, the binder is selected from one or more combinations of polyvinyl alcohol, polyethylene glycol, and sodium carboxymethyl cellulose; even more preferably, the mass ratio of the active catalytic component, the precursor of the matrix material, the solvent, and the binder is (5-30):100:(100-300):(2-10); More preferably, the step of coating the coating preparation slurry onto the inner wall surface of the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger is achieved by spraying and / or dipping and / or brushing. More preferably, the drying is carried out at 110-180°C (e.g., 120°C); More preferably, the sintering is carried out at 400-800°C; even more preferably, the sintering time is 3-5 hours (e.g., 2 hours). More preferably, the sintering is carried out in an oxygen-containing atmosphere; for example, an air atmosphere; More preferably, before performing the step of applying the coating preparation slurry to the inner wall surface of the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger, the inner wall surface of the cold fluid flow channel is pretreated, specifically including degreasing, derusting and roughening.

[0018] According to a specific embodiment of the first aspect of the present invention, preferably, the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger is a tube-side flow channel.

[0019] According to a specific embodiment of the first aspect of the present invention, preferably, the structure of the amine-rich liquid vaporization heat exchanger may be, but is not limited to, the structure of an existing heat exchanger; For example, the rich amine liquid vaporization heat exchanger adopts a typical heat exchanger structure - a shell-and-tube structure. The rich amine liquid vaporization heat exchanger is provided with a shell and heat transfer tubes disposed inside the shell. The internal flow channel of the heat transfer tube is the tube-side flow channel, and the flow channel between the shell and the heat transfer tube is the shell-side flow channel. One of the shell-side flow channel and the tube-side flow channel serves as a cold fluid flow channel, and the other serves as a hot fluid flow channel. Cold fluid refers to the fluid that is heated in a heat exchanger (i.e., the fluid used to cool down), while hot fluid is the fluid used to heat in a heat exchanger (i.e., the fluid used to cool down).

[0020] Secondly, the present invention provides an amine liquid recovery system, wherein the amine liquid recovery system is provided with a primary lean-rich amine liquid heat exchanger, a primary diversion device (with at least two rich amine liquid outlets), a secondary lean-rich amine liquid heat exchanger, a secondary diversion device (with at least two rich amine liquid outlets), a tertiary lean-rich amine liquid heat exchanger, a gas-liquid separation device, and a desorption tower; wherein the tertiary lean-rich amine liquid heat exchanger is the rich amine liquid vaporization heat exchanger provided in the first aspect of the present invention. The cold fluid inlet of the primary lean-rich amine liquid heat exchanger is connected to the rich amine liquid outlet of the carbon dioxide absorption tower; the cold fluid inlet of the primary lean-rich amine liquid heat exchanger is connected to the rich amine liquid inlet of the primary diversion device; the first rich amine liquid outlet of the primary diversion device is connected to the cold fluid inlet of the secondary lean-rich amine liquid heat exchanger; the cold fluid inlet of the secondary lean-rich amine liquid heat exchanger is connected to the rich amine liquid inlet of the secondary diversion device; the first rich amine liquid outlet of the secondary diversion device is connected to the cold fluid inlet of the tertiary lean-rich amine liquid heat exchanger; the cold fluid inlet of the tertiary lean-rich amine liquid heat exchanger is connected to the material inlet of the gas-liquid separation device; and the liquid phase outlet of the gas-liquid separation device is connected to the material inlet of the desorption tower. The desorption tower's lean amine liquid outlet is connected to the inlet of the hot fluid flow channel of the tertiary lean-rich amine liquid heat exchanger; the tertiary lean-rich amine liquid heat exchanger's hot fluid flow channel outlet is connected to the inlet of the secondary lean-rich amine liquid heat exchanger; the secondary lean-rich amine liquid heat exchanger's hot fluid flow channel outlet is connected to the inlet of the primary lean-rich amine liquid heat exchanger; and the primary lean-rich amine liquid heat exchanger's hot fluid flow channel outlet is used to connect to the organic amine absorbent inlet of the carbon dioxide absorption tower. The primary diversion device, except for the first rich amine liquid outlet, has its other rich amine liquid outlets connected to the material inlet of the desorption tower; the secondary diversion device, except for the first rich amine liquid outlet, has its other rich amine liquid outlets connected to the material inlet of the desorption tower.

[0021] When using waste heat to reduce energy consumption during the desorption process of high-efficiency composite amine solutions with low desorption temperatures, problems such as poor heat exchange, limited energy reduction, and abnormal equipment operation often occur. The reason for this is that the amine-rich liquid formed by the absorption of carbon dioxide by the high-efficiency composite amine solution with low desorption temperatures is prone to desorption during waste heat exchange, generating a large amount of gas and forming a gas-liquid two-phase amine-rich liquid. This severely affects the heat exchanger's heat exchange efficiency, leading to poor heat exchange and limited energy reduction. Furthermore, the large amount of gas can easily form gas blockages during flow, preventing the amine-rich liquid from smoothly entering the desorption tower, resulting in abnormal equipment operation. Therefore, this invention proposes a special amine recovery system integrating multi-stage heat exchange, multi-stage flow splitting, heat exchange desorption, and gas-liquid separation.

[0022] The amine liquid recovery system provided by this invention, through the combination of multi-stage heat exchange, multi-stage diversion, heat exchange desorption, and gas-liquid separation, can significantly raise the temperature of rich amine liquid by utilizing waste heat resources while reducing the adverse effects of gas-liquid two-phase rich amine liquid on the heat exchange effect and avoiding the flow of a large amount of gas-liquid two-phase rich amine liquid in the system. Thus, it can effectively ensure the phase stability within the system while making full use of waste heat resources to reduce energy consumption.

[0023] According to a specific embodiment of the second aspect of the present invention, preferably, the first-stage lean-rich amine liquid heat exchanger is capable of heating the rich amine liquid to 80-85% of the initial desorption temperature of carbon dioxide in the rich amine liquid, the second-stage lean-rich amine liquid heat exchanger is capable of heating the rich amine liquid to 105-120% of the initial desorption temperature of carbon dioxide in the rich amine liquid, and the third-stage lean-rich amine liquid heat exchanger is capable of heating the rich amine liquid to 125% or more of the initial desorption temperature of carbon dioxide in the rich amine liquid; In this preferred technical solution, the rich amine liquid after heat exchange in the first-stage lean-rich amine liquid heat exchanger does not reach the desorption temperature and remains in a single liquid phase state with stable flow; the rich amine liquid after heat exchange in the second-stage lean-rich amine liquid heat exchanger reaches the initial desorption temperature, at which point the rich amine liquid undergoes a very small amount of desorption, but can still maintain a stable liquid phase flow state; the rich amine liquid in the third-stage lean-rich amine liquid heat exchanger makes full use of waste heat resources for heat exchange and desorption, forming a gas-liquid two-phase rich amine liquid; the gas-liquid two-phase rich amine liquid formed in the third-stage lean-rich amine liquid heat exchanger enters the gas-liquid separation equipment for gas-liquid separation, forming a stable gas phase flow and liquid phase flow. More preferably, the initial carbon dioxide desorption temperature of the rich amine liquid is 60-80℃; the first-stage lean rich amine liquid heat exchanger can heat the rich amine liquid to 55-65℃; the second-stage lean rich amine liquid heat exchanger can heat the rich amine liquid to 75-85℃; and the third-stage lean rich amine liquid heat exchanger can heat the rich amine liquid to 100℃ and above.

[0024] According to a specific embodiment of the second aspect of the present invention, preferably, the primary diversion device and the secondary diversion device are capable of achieving a ratio of (14-36):100 between the total mass of the rich amine liquid discharged from the secondary diversion device (excluding the first rich amine liquid outlet) and the mass of the rich amine liquid entering the primary diversion device, and a ratio of (42-72):100 between the mass of the rich amine liquid discharged from the first rich amine liquid outlet of the secondary diversion device and the mass of the rich amine liquid entering the primary diversion device. In this preferred technical solution, during the process of significantly raising the temperature of the rich amine liquid using waste heat resources, the diversion control of the primary diversion device and the secondary diversion device effectively ensures that the rich amine liquid entering the tertiary lean rich amine liquid heat exchanger can fully exchange heat and desorb using waste heat resources. At the same time, it effectively controls the flow rate of the rich amine liquid in the system that has reached the initial desorption temperature, avoiding the flow of a large amount of gas-liquid two-phase rich amine liquid in the system. More preferably, the primary diversion device can achieve a mass ratio of the rich amine liquid discharged from the first rich amine liquid outlet to the total mass of the rich amine liquid discharged from all rich amine liquid outlets of (7-9):10; the secondary diversion device can achieve a mass ratio of the rich amine liquid discharged from the first rich amine liquid outlet to the total mass of the rich amine liquid discharged from all rich amine liquid outlets of (6-8):10.

[0025] According to a specific embodiment of the second aspect of the present invention, preferably, the amine liquid recovery system is further provided with a low-grade waste heat heating device, which is provided on the connecting pipeline between the second rich amine liquid outlet of the primary diversion device and the material inlet of the desorption tower, and the low-grade waste heat heating device is used to heat the rich amine liquid using low-grade waste heat resources. The low-grade waste heat resources refer to waste heat resources with a temperature of 75-85℃. More preferably, the low-grade waste heat resource can be, but is not limited to, using the hot water from the plant area of ​​the amine recovery system; More preferably, the material inlet of the desorption tower connected to the second amine liquid outlet of the primary diversion device is located at position A of the desorption tower, and the temperature at position A of the desorption tower is 105-115% of the temperature of the amine liquid after being heated by the low-grade waste heat heating device; even more preferably, the temperature at position A of the desorption tower is 80-90°C. More preferably, the primary diversion device can achieve a ratio of (1-3):10 between the mass of the rich amine liquid discharged from the second rich amine liquid outlet and the total mass of the rich amine liquid discharged from all rich amine liquid outlets.

[0026] According to a specific embodiment of the second aspect of the present invention, preferably, the primary diversion device is provided with two rich amine liquid outlets.

[0027] According to a specific embodiment of the second aspect of the present invention, preferably, the amine liquid recovery system is further provided with a medium-range waste heat heating device, which is provided on the connecting pipeline between the second rich amine liquid outlet of the secondary diversion device and the material inlet of the desorption tower, and the medium-range waste heat heating device is used to heat the rich amine liquid using medium-range waste heat resources; Among them, the medium-grade waste heat resources refer to waste heat resources with a temperature of 85-95℃; More preferably, the medium-grade waste heat resource may, but is not limited to, use the flue gas from the plant area of ​​the amine liquid recovery system; More preferably, the material inlet of the desorption tower connected to the second amine liquid outlet of the secondary diversion device is located at position B of the desorption tower, and the temperature at position B of the desorption tower is 95-110% of the temperature of the amine liquid after being heated by the medium-range waste heat heating device; even more preferably, the temperature at position B of the desorption tower is 85-95°C. More preferably, the secondary diversion device can achieve a ratio of (1-2):10 between the mass of the rich amine liquid discharged from the second rich amine liquid outlet and the total mass of the rich amine liquid discharged from all rich amine liquid outlets.

[0028] According to a specific embodiment of the second aspect of the present invention, preferably, the material inlet of the desorption tower connected to the third amine-rich liquid outlet of the secondary diversion device is located at the top of the desorption tower. This preferred technical solution can reduce the consumption of circulating cooling water required for condensation in the condensation reflux module at the top of the desorption tower; More preferably, no equipment for heating or cooling the amine solution is installed on the connecting pipeline between the third amine-rich liquid outlet of the secondary diversion device and the material inlet of the desorption tower. More preferably, the secondary diversion device can achieve a ratio of (1-2):10 between the mass of the rich amine liquid discharged from the third rich amine liquid outlet and the total mass of the rich amine liquid discharged from all rich amine liquid outlets.

[0029] According to a specific embodiment of the second aspect of the present invention, preferably, the secondary diversion device is provided with three rich amine liquid outlets.

[0030] According to a specific embodiment of the second aspect of the present invention, preferably, the gas phase outlet of the gas-liquid separation device is connected to the material inlet of the desorption tower; More preferably, the material inlet of the desorption tower connected to the gas phase outlet of the gas-liquid separation device is located on the condensation reflux module at the top of the desorption tower.

[0031] According to a specific embodiment of the second aspect of the present invention, preferably, the amine recovery system is further provided with a three-stage diversion device and a high-grade waste heat heating device; the three-stage diversion device and the high-grade waste heat heating device are sequentially arranged on the connecting pipeline between the liquid phase outlet of the gas-liquid separation device and the material inlet of the desorption tower. Specifically, the liquid phase outlet of the gas-liquid separation device is connected to the amine-rich liquid inlet of the three-stage diversion device, the first amine-rich liquid outlet of the three-stage diversion device is connected to the material inlet of the desorption tower, the second amine-rich liquid outlet of the three-stage diversion device is connected to the material inlet of the high-grade waste heat heating device, and the material outlet of the high-grade waste heat heating device is connected to the material inlet of the desorption tower. Among them, the high-grade waste heat resources refer to waste heat resources with a temperature of 105-115℃; More preferably, the high-grade waste heat resource may, but is not limited to, the condensate from the reboiling module of the desorption tower of the amine recovery system; More preferably, the material inlet of the desorption tower connected to the second amine liquid outlet of the three-stage diversion device is located at position C of the desorption tower, and the temperature at position C of the desorption tower is 90-100% of the temperature of the amine liquid after being heated by the high-grade waste heat heating equipment; even more preferably, the temperature at position C of the desorption tower is 100-110°C. More preferably, the material inlet of the desorption tower connected to the first amine-rich liquid outlet of the three-stage diversion device is located at position D of the desorption tower, and the temperature at position D of the desorption tower is 95-105% of the temperature of the amine-rich liquid discharged from the liquid phase outlet of the gas-liquid separation device; even more preferably, the temperature at position D of the desorption tower is 100-110°C. More preferably, the three-stage diversion device can achieve a ratio of (1-3):10 between the mass of the rich amine liquid discharged from the second rich amine liquid outlet and the total mass of the rich amine liquid discharged from all rich amine liquid outlets. More preferably, the three-stage diversion device is equipped with two amine-rich liquid outlets.

[0032] According to a specific embodiment of the second aspect of the present invention, preferably, the amine liquid recovery system is further provided with a first rich amine liquid transfer pump, which is located at the inlet of the cold fluid flow channel of the first-stage lean rich amine liquid heat exchanger.

[0033] According to a specific embodiment of the second aspect of the present invention, preferably, the amine recovery system is further provided with a lean liquid cooler, which is located at the outlet of the hot fluid flow channel of the primary lean-rich amine liquid heat exchanger.

[0034] According to a specific embodiment of the second aspect of the present invention, preferably, the amine liquid recovery system is further provided with a second rich amine liquid transfer pump, which is located at the liquid phase outlet of the gas-liquid separation device.

[0035] According to a specific embodiment of the second aspect of the present invention, preferably, the desorption tower may be, but is not limited to, an existing desorption tower; For example, the desorption tower includes a tower body, a condensation reflux module, and a reboiling module. The condensation reflux module includes a cooler, a reflux tank, and a reflux pump. The material outlet of the cooler is connected to the material inlet of the reflux tank. The gas phase outlet of the reflux tank is used for gas discharge, and the liquid phase outlet of the reflux tank is connected to the pump inlet of the reflux pump. The reboiling module includes a reboiler. The gas phase outlet at the top of the tower body is connected to the material inlet of the cooler in the condensation reflux module. The pump outlet of the reflux pump in the condensation reflux module is connected to the liquid phase reflux port at the top of the tower body. The liquid phase outlet at the bottom of the tower body is connected to the material inlet of the reboiler. The gas phase material outlet of the reboiler is connected to the gas phase reflux port at the bottom of the tower body. The liquid phase material outlet of the reboiler is used for discharging lean amine solution. The reboiler also includes a heating steam inlet and a condensate outlet.

[0036] According to a specific embodiment of the second aspect of the present invention, preferably, the gas-liquid separation device may be, but is not limited to, a flash tank.

[0037] According to a specific embodiment of the second aspect of the present invention, preferably, the primary diversion device may, but is not limited to, employ a static diversion device, a dynamic diversion device, a flow control diversion device, a diversion valve, or other devices capable of diverting flow.

[0038] According to a specific embodiment of the second aspect of the present invention, preferably, the secondary diversion device may, but is not limited to, employ a static diverter, a dynamic diverter, a flow control diverter, a diversion valve, or other devices capable of diverting flow.

[0039] According to a specific embodiment of the second aspect of the present invention, preferably, the three-stage diversion device may, but is not limited to, employ a static diverter, a dynamic diverter, a flow control diverter, a diversion valve, or other devices capable of diverting flow.

[0040] According to a specific embodiment of the second aspect of the present invention, preferably, the low-grade waste heat heating device may, but is not limited to, employ a heat exchanger.

[0041] According to a specific embodiment of the second aspect of the present invention, preferably, the medium-range waste heat heating device may, but is not limited to, employ a heat exchanger.

[0042] According to a specific embodiment of the second aspect of the present invention, preferably, the high-grade waste heat heating equipment may, but is not limited to, employ a heat exchanger.

[0043] Thirdly, the present invention provides a method for recovering amine liquid, wherein the amine liquid recovery method is performed using the amine liquid recovery system provided in the second aspect of the present invention, and the amine liquid recovery method includes: The amine-rich liquid obtained by capturing carbon dioxide using a high-efficiency composite amine absorbent enters a first-stage amine-lean heat exchanger, where it exchanges heat with the amine-lean liquid from a second-stage amine-lean heat exchanger to obtain the first post-heat exchange amine-rich liquid; wherein, the temperature of the first post-heat exchange amine-rich liquid is 80-85% of the initial carbon dioxide desorption temperature of the amine-rich liquid. After the first heat exchange, the rich amine liquid enters the first-stage diversion device for diversion, resulting in rich amine liquid stream A and the remaining rich amine liquid stream other than rich amine liquid stream A, i.e., rich amine liquid stream B. Amine-rich liquid stream A enters a secondary lean amine-rich liquid heat exchanger, where it exchanges heat with the lean amine liquid from the tertiary lean amine-rich liquid heat exchanger to obtain a second heat-exchanged amine-rich liquid; wherein, the temperature of the second heat-exchanged amine-rich liquid is 105-120% of the initial carbon dioxide desorption temperature of the amine-rich liquid. After the second heat exchange, the rich amine liquid enters the secondary diversion device for diversion, resulting in rich amine liquid stream C and the remaining rich amine liquid stream D excluding rich amine liquid stream C. The rich amine liquid stream C enters the three-stage lean rich amine liquid heat exchanger, where it exchanges heat and undergoes carbon dioxide desorption with the lean amine liquid from the desorption tower, resulting in a rich amine liquid after heat exchange and desorption; wherein, the temperature of the rich amine liquid after heat exchange and desorption is 125% or more of the initial carbon dioxide desorption temperature of the rich amine liquid. After heat exchange and desorption, the amine-rich liquid enters a gas-liquid separation device for gas-liquid separation to obtain gaseous and liquid products. The rich amine liquid stream B, the rich amine liquid stream D, and the liquid phase product obtained from the gas-liquid separation equipment enter the desorption tower for carbon dioxide desorption, resulting in a lean amine liquid and carbon dioxide gas. The lean amine liquid obtained from the desorption tower flows sequentially through the three-stage lean-rich amine liquid heat exchanger, the two-stage lean-rich amine liquid heat exchanger, and the first-stage lean-rich amine liquid heat exchanger, where it exchanges heat with the rich amine liquid. Wherein, the mass ratio of the rich amine liquid stream D to the mass of the rich amine liquid after the first heat exchange is (14-36):100, and the mass ratio of the rich amine liquid stream B to the mass of the rich amine liquid after the first heat exchange is (42-72):100. Among them, the high-efficiency composite amine absorbent refers to the organic amine solution absorbent with an initial carbon dioxide desorption temperature of no more than 80°C.

[0044] According to a specific embodiment of the third aspect of the present invention, preferably, the initial desorption temperature of the carbon dioxide-rich liquid in the high-efficiency composite amine absorbent is 60-80°C.

[0045] According to a specific embodiment of the third aspect of the present invention, preferably, the desorption heat of the rich amine liquid of the high-efficiency composite amine absorbent does not exceed (i.e., is less than or equal to) 70 kJ / mol.

[0046] According to a specific embodiment of the third aspect of the present invention, preferably, the components of the high-efficiency composite amine absorbent include a main absorbent, an activating absorption promoter, and a solvent; The main absorbent is selected from one or more of the following amine agents: ethanolamine, N-methyldiethanolamine, hydroxyethyl ethylenediamine, 2-amino-2-methyl-1-propanol (AMP), diisopropanolamine, etc. The activation and absorption promoter is selected from one or more of the following cyclic amines: hydroxyethylpiperazine, N-aminopropylmorpholine, 2-(2-aminoethyl)pyridine, N-ethylpiperazine, piperazine, and N-methylpiperazine. Of which, based on the total mass of the high-efficiency compound amine absorbent as 100%, the mass content of the main absorbent is 10%-30%, and the mass content of the activating absorption promoter is 1%-10%; More preferably, the high-efficiency composite amine absorbent further includes a regeneration optimizer; the regeneration optimizer is a soluble metal salt; based on the total mass of the high-efficiency composite amine absorbent as 100%, the mass content of the regeneration optimizer is 0.1%-3%; even more preferably, the regeneration optimizer is selected from one or more combinations of soluble metal salts such as nitrates and sulfates of metals such as iron, cobalt, nickel, copper, silver, gold, zinc, manganese, and gallium; More preferably, the components of the high-efficiency composite amine absorbent further include an antioxidant; the antioxidant is selected from one or more combinations of sodium sulfite, sodium persulfate, sodium thiosulfate, sodium phosphite, etc.; based on the total mass of the high-efficiency composite amine absorbent as 100%, the mass content of the antioxidant is 0.1%-2%.

[0047] According to a specific embodiment of the third aspect of the present invention, preferably, the initial desorption temperature of the rich amine solution is 60-80°C; the temperature of the rich amine solution after the first heat exchange is 55-65°C; the temperature of the rich amine solution after the second heat exchange is 75-85°C; and the temperature of the rich amine solution after heat exchange desorption is 100°C or higher. More preferably, the mass ratio of the rich amine liquid stream A to the sum of the masses of the rich amine liquid stream A and the rich amine liquid stream B is (7-9):10; the mass ratio of the rich amine liquid stream C to the sum of the masses of the rich amine liquid stream C and the rich amine liquid stream D is (6-8):10. More preferably, part or all of the rich amine liquid stream B1 from the rich amine liquid stream B enters a low-grade waste heat heating device, where it is heated using low-grade waste heat resources to obtain rich amine liquid stream E, which then enters the desorption tower for carbon dioxide desorption; wherein, the low-grade waste heat resources refer to waste heat resources with a temperature of 75-85℃; further preferably, the low-grade waste heat resources can be, but are not limited to, using hot water from the plant area of ​​the amine liquid recovery system; further preferably, the mass ratio of the rich amine liquid stream B1 to the sum of the masses of the rich amine liquid stream A and the rich amine liquid stream B is (1-3):10; further preferably, the rich amine liquid stream E enters the desorption tower from position A, and the temperature at position A is 105-115% of the temperature of the rich amine liquid stream E, for example, 80-90℃; further preferably, the rich amine liquid stream B1 is all of the rich amine liquid stream B. More preferably, part or all of the rich amine liquid stream D1 from the rich amine liquid stream D enters a medium-range waste heat heating device, where it is heated using medium-range waste heat resources to obtain rich amine liquid stream F, which then enters the desorption tower for carbon dioxide desorption; wherein, the medium-range waste heat resources refer to waste heat resources with a temperature of 85-95℃; further preferably, the medium-range waste heat resources may be, but are not limited to, the flue gas from the plant area of ​​the amine liquid recovery system; further preferably, the mass ratio of the rich amine liquid stream D1 to the sum of the masses of the rich amine liquid stream C and the rich amine liquid stream D is (1-2):10; further preferably, the rich amine liquid stream F enters the desorption tower from position B, and the temperature at position B is 95-110% of the temperature of the rich amine liquid stream F, for example, 85-95℃; further preferably, the rich amine liquid stream D1 is a portion of the rich amine liquid stream D; More preferably, some or all of the rich amine liquid stream D2 from the rich amine liquid stream D enters the desorption tower from the top of the desorption tower; even more preferably, the mass ratio of the rich amine liquid stream D2 to the sum of the masses of the rich amine liquid stream C and the rich amine liquid stream D is (1-2):10; even more preferably, the rich amine liquid stream D2 is a portion of the rich amine liquid stream D. More preferably, the liquid product obtained from the gas-liquid separation device enters a three-stage diversion device for diversion, resulting in a rich amine liquid stream G and a residual rich amine liquid stream H excluding G. The rich amine liquid stream G enters a high-grade waste heat heating device, where it is heated using high-grade waste heat resources to obtain a rich amine liquid stream I, which then enters the desorption tower for carbon dioxide desorption. The high-grade waste heat resources refer to waste heat resources with a temperature of 105-115℃. Further preferably, the high-grade waste heat resources can be, but are not limited to, the condensate from the reboiling module of the desorption tower in the amine recovery system. Further preferably, the rich amine liquid stream G... The mass ratio of amine liquid stream G to the combined mass of the rich amine liquid stream G and the rich amine liquid stream H is (1-3):10; more preferably, the rich amine liquid stream I enters the desorption tower from position C, and the temperature at position C is 90-100% of the temperature of the rich amine liquid stream I, for example, 100-110°C; more preferably, the rich amine liquid stream D1 is a portion of the rich amine liquid stream D; more preferably, the rich amine liquid stream H enters the desorption tower from position D, and the temperature at position D is 95-105% of the temperature of the rich amine liquid stream H, for example, 100-110°C; More preferably, the bottom temperature of the desorption tower is 100-115℃, the top temperature is 75-90℃, and the pressure of the desorption tower is 0.04-0.15MPa; More preferably, the ratio of the mass flow rate of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger to the mass flow rate of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger is 1:0.9-0.97. More preferably, the temperature of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger is 41-55°C; More preferably, the temperature of the lean amine liquid entering the three-stage lean-rich amine liquid heat exchanger is 100-115°C.

[0048] According to a specific embodiment of the third aspect of the present invention, preferably, the gaseous product obtained by the gas-liquid separation device enters the desorption tower for carbon dioxide desorption; More preferably, the gaseous product obtained by the gas-liquid separation device enters the desorption tower from the condensation reflux module at the top of the desorption tower.

[0049] Fourthly, the present invention provides a carbon dioxide capture device, wherein the carbon dioxide capture device is provided with a carbon dioxide absorption tower and an amine recovery system; the amine recovery system adopts the amine recovery system provided in the second aspect of the present invention; The rich amine liquid outlet of the carbon dioxide absorption tower is connected to the cold fluid flow channel inlet of the amine liquid recovery system; the hot fluid flow channel outlet of the primary lean-rich amine liquid heat exchanger of the amine liquid recovery system is connected to the organic amine absorbent inlet of the carbon dioxide absorption tower. The carbon dioxide absorption tower is also equipped with a flue gas inlet and a gas phase outlet.

[0050] According to a specific embodiment of the fourth aspect of the present invention, preferably, the carbon dioxide capture device further includes a flue gas pretreatment device, which is disposed at the flue gas inlet of the carbon dioxide absorption tower.

[0051] According to a specific embodiment of the fourth aspect of the present invention, preferably, when the amine liquid recovery system is provided with a medium-range waste heat heating device, the medium-range waste heat resource inlet of the medium-range waste heat heating device is used to connect with the flue gas source to be treated, and the medium-range waste heat resource outlet of the medium-range waste heat heating device is connected with the flue gas inlet of the carbon dioxide absorption tower.

[0052] Fifthly, the present invention provides a carbon dioxide capture method, wherein the carbon dioxide capture method is performed using the carbon dioxide capture device provided in the fourth aspect of the present invention, and the carbon dioxide capture method includes: The high-efficiency composite amine absorbent and the flue gas to be treated enter the carbon dioxide absorption tower. In the carbon dioxide absorption tower, the high-efficiency composite amine absorbent captures the carbon dioxide in the flue gas to be treated, and a rich amine liquid is obtained. The amine-rich solution is recovered using the amine recovery method provided in the third aspect of this invention to obtain a lean amine solution; The lean amine liquid from the primary lean-rich amine liquid heat exchanger is cooled and then reintroduced into the carbon dioxide absorption tower as a high-efficiency composite amine absorbent to capture carbon dioxide in the flue gas to be treated.

[0053] According to a specific embodiment of the fifth aspect of the present invention, preferably, the temperature of the high-efficiency composite amine absorbent entering the carbon dioxide absorption tower is 40-45°C.

[0054] According to a specific embodiment of the fifth aspect of the present invention, preferably, the temperature of the flue gas to be treated entering the carbon dioxide absorption tower is 35-45°C.

[0055] According to a specific embodiment of the fifth aspect of the present invention, preferably, the pressure of the carbon dioxide absorption tower is 0.004-0.015 MPa.

[0056] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: 1. The amine-rich liquid vaporization heat exchanger provided by this invention features a specific coating on the inner wall surface of the cold fluid flow channel. This coating enables efficient desorption of carbon dioxide from the amine-rich liquid by fully utilizing the thermal energy of the hot fluid. When used in the amine recovery process of the high-efficiency composite amine carbon dioxide capture technology, it effectively helps the amine recovery process fully utilize waste heat resources, reduce energy consumption, and ensure normal equipment operation. The amine-rich liquid vaporization heat exchanger provided by this invention has extremely high industrial application value.

[0057] 2. The amine liquid recovery system and method provided by the technical solution of the present invention, through the combination of multi-stage heat exchange, multi-stage diversion, heat exchange desorption, and gas-liquid separation, can effectively ensure the phase stability within the system while making full use of waste heat resources to reduce energy consumption.

[0058] In the preferred technical solution, the effective utilization of low-grade waste heat outside the carbon dioxide capture process can be achieved, which not only further reduces the energy consumption of the carbon dioxide capture process, but also helps to achieve energy optimization throughout the plant, thus achieving the goal of comprehensive energy conservation and emission reduction.

[0059] 3. The carbon dioxide capture device and method provided by the present invention, through the cooperation of a carbon dioxide absorption tower and a special amine liquid recovery system, achieves low-energy-consumption and smooth operation of the high-efficiency composite amine carbon dioxide capture technology.

[0060] 4. The amine recovery system and method, and carbon dioxide capture device and method provided by the technical solution of the present invention have reasonable process flow, low implementation difficulty, significant energy saving effect, and are easy to promote and apply. Attached Figure Description

[0061] Figure 1 This is a schematic diagram of the carbon dioxide capture device provided in Example 2.

[0062] Figure 2 A schematic diagram of the carbon dioxide capture device provided for Comparative Example 5. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below. Here, the illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0064] In this invention, the amine-rich liquid refers to the liquid-phase product after the organic amine absorbent absorbs carbon dioxide.

[0065] In this invention, the lean amine solution refers to the regenerated organic amine absorbent obtained after the rich amine solution completes the carbon dioxide desorption.

[0066] The initial desorption temperature of carbon dioxide in amine-rich liquid refers to the lowest temperature at which continuous CO2 desorption begins in amine-rich liquid under normal pressure. This temperature can be determined in the laboratory by heating the amine-rich liquid under normal pressure and observing the lowest temperature at which small bubbles are continuously generated.

[0067] Example 1

[0068] This embodiment provides a rich amine liquid vaporization heat exchanger.

[0069] The inner wall surface of the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger provided in this embodiment is coated with a coating; the coating includes a matrix material and an active catalytic component supported on the matrix material. The matrix material is silicon carbide foam ceramic material; the active catalytic component is a mixture of nano-titanium dioxide (TiO2), nano-zirconium oxide (ZrO2), and nano-alumina (Al2O3) in a mass ratio of 40:30:30.

[0070] The surface roughness Ra of the coating is 20 micrometers.

[0071] The coating is 200 micrometers thick.

[0072] The coating was prepared in the following manner: First, the active catalytic component (i.e., a mixture of nano-titanium dioxide, nano-zirconium oxide, and nano-alumina in a mass ratio of 40:30:30), the precursor of the matrix material (i.e., silicon carbide porous ceramic precursor powder containing silicon carbide (SiC) powder in a mass ratio of 80:4:10:6, sintering aid magnesium oxide, binder methylcellulose, and pore-forming agent graphite), and the solvent deionized water and binder polyvinyl alcohol binder are mixed and ball-milled for 4 hours to obtain a coating preparation slurry with a solid content of 60wt%; wherein, the mass ratio of the active catalytic component, the matrix material precursor, the solvent, and the binder is 10:100:180:6. The stainless steel inner wall surface of the cold fluid flow channel of the heat exchanger was subjected to degreasing, rust removal and sandblasting roughening treatment in sequence; then, the coating preparation slurry was uniformly sprayed onto the inner wall surface using air spraying method; subsequently, it was dried at 120°C for 2 hours; finally, it was sintered at 800°C for 2 hours in an oxygen atmosphere (air atmosphere) to form a coating with a thickness of 200 micrometers and a surface roughness Ra of 20 micrometers on the inner wall surface of the cold fluid flow channel of the heat exchanger.

[0073] The amine-rich liquid vaporization heat exchanger provided in this embodiment adopts a shell-and-tube structure, specifically consisting of a shell and heat transfer tubes disposed inside the shell. The internal flow channel of the heat transfer tubes is the tube-side flow channel, and the flow channel between the shell and the heat transfer tubes is the shell-side flow channel. The tube-side flow channel serves as the cold fluid flow channel, and the shell-side flow channel serves as the hot fluid flow channel.

[0074] Comparative Example 1

[0075] This comparative example provides a heat exchanger.

[0076] The only difference between the heat exchanger provided in this comparative example and the amine-rich liquid vaporization heat exchanger provided in Example 1 is that the inner wall surface of the cold fluid flow channel is not coated and remains a conventional stainless steel surface.

[0077] Comparative Example 2

[0078] This comparative example provides a heat exchanger.

[0079] The only difference between the heat exchanger provided in this comparative example and the amine-rich liquid vaporization heat exchanger provided in Example 1 is that the coating on the inner wall surface of the cold fluid flow channel is a polytetrafluoroethylene (PTFE) anti-corrosion coating, which has a smooth surface and no catalytic activity.

[0080] Example 2

[0081] This embodiment provides an amine liquid recovery system and a carbon dioxide capture device.

[0082] The carbon dioxide capture device provided in this embodiment includes a carbon dioxide absorption tower 01 and an amine liquid recovery system provided in this embodiment, the structure of which is as follows: Figure 1 As shown.

[0083] The amine recovery system provided in this embodiment includes a primary amine-rich liquid heat exchanger 03, a primary diversion device 21, a secondary amine-rich liquid heat exchanger 15, a secondary diversion device 22, a tertiary amine-rich liquid heat exchanger 17, a gas-liquid separation device 18, a tertiary diversion device 13, and a desorption tower 06; wherein, the tertiary amine-rich liquid heat exchanger 17 adopts the amine-rich liquid vaporization heat exchanger provided in Embodiment 1 of the present invention. The cold fluid outlet of the primary lean-rich amine liquid heat exchanger 03 is connected to the rich amine liquid inlet of the primary diversion device 21; the first rich amine liquid outlet of the primary diversion device 21 is connected to the cold fluid outlet of the secondary lean-rich amine liquid heat exchanger 15; the cold fluid outlet of the secondary lean-rich amine liquid heat exchanger 15 is connected to the rich amine liquid inlet of the secondary diversion device 22; the first rich amine liquid outlet of the secondary diversion device 22 is connected to the cold fluid outlet of the tertiary lean-rich amine liquid heat exchanger 17; and the cold fluid outlet of the tertiary lean-rich amine liquid heat exchanger 17 is connected to the material outlet of the gas-liquid separation device 18. Inlet connection; the liquid phase outlet of the gas-liquid separation device 18 is connected to the rich amine liquid inlet of the three-stage diversion device 13; the first rich amine liquid outlet of the three-stage diversion device 13 is connected to the material inlet of the desorption tower 06; the lean amine liquid outlet of the desorption tower 06 is connected to the hot fluid flow channel inlet of the three-stage lean-rich amine liquid heat exchanger 17; the hot fluid flow channel outlet of the three-stage lean-rich amine liquid heat exchanger 17 is connected to the hot fluid flow channel inlet of the two-stage lean-rich amine liquid heat exchanger 15; the hot fluid flow channel outlet of the two-stage lean-rich amine liquid heat exchanger 15 is connected to the hot fluid flow channel inlet of the first-stage lean-rich amine liquid heat exchanger 03.

[0084] In the amine recovery system provided in this embodiment, the primary diversion device 21 is equipped with two rich amine liquid outlets.

[0085] The amine recovery system provided in this embodiment is also equipped with a low-grade waste heat heating device 14. The second rich amine liquid outlet of the primary diversion device 21 is connected to the material inlet of the low-grade waste heat heating device 14, and the material outlet of the low-grade waste heat heating device 14 is connected to the material inlet of the desorption tower 06 located at position A of the desorption tower 06 (i.e., the low-grade waste heat heating device 14 is located on the connecting pipeline between the second rich amine liquid outlet of the primary diversion device 21 and the material inlet of the desorption tower 06 located at position A of the desorption tower 06). The low-grade waste heat heating device 14 is used to heat the rich amine liquid using low-grade waste heat resources. Specifically, the low-grade waste heat resources are hot water at a temperature of about 80°C in the plant area using the amine recovery system, i.e., the waste heat resource inlet of the low-grade waste heat heating device 14 is connected to the low-grade waste heat resource supply pipeline.

[0086] In the amine recovery system provided in this embodiment, the secondary diversion device 22 is equipped with three rich amine liquid outlets.

[0087] The amine recovery system provided in this embodiment also includes a medium-range waste heat heating device 16. The second rich amine liquid outlet of the secondary diversion device 22 is connected to the material inlet of the medium-range waste heat heating device 16, and the material outlet of the medium-range waste heat heating device 16 is connected to the material inlet of the desorption tower 06 located at position B of the desorption tower 06 (i.e., the medium-range waste heat heating device 16 is located on the connecting pipeline between the second rich amine liquid outlet of the secondary diversion device 22 and the material inlet of the desorption tower 06 located at position B of the desorption tower 06). The medium-range waste heat heating device 16 is used to heat the rich amine liquid using medium-range waste heat resources. The medium-range waste heat resources are the flue gas to be treated in the plant area where the amine recovery system is used, with a temperature of about 90°C. That is, the waste heat resource inlet of the medium-range waste heat heating device 16 is connected to the medium-range waste heat resource supply pipeline.

[0088] In the amine recovery system provided in this embodiment, the third rich amine liquid outlet of the secondary diversion device 22 is connected to the material inlet of the desorption tower 06 located at the top of the desorption tower 06. No equipment for heating or cooling the rich amine liquid is installed on the connecting pipeline between the third rich amine liquid outlet of the secondary diversion device 22 and the material inlet of the desorption tower 06.

[0089] In the amine recovery system provided in this embodiment, the gas phase outlet of the gas-liquid separation device 18 is connected to the material inlet of the desorption tower 06, which is located on the condensation reflux module at the top of the desorption tower 06.

[0090] In the amine recovery system provided in this embodiment, the three-stage diversion device is equipped with two rich amine liquid outlets.

[0091] The amine recovery system provided in this embodiment is also equipped with a high-grade waste heat heating device 05. The second rich amine liquid outlet of the three-stage diversion device 13 is connected to the material inlet of the high-grade waste heat heating device 05, and the material outlet of the high-grade waste heat heating device 05 is connected to the material inlet of the desorption tower 06 located at position C of the desorption tower 06. The high-grade waste heat heating device 05 is used to heat the rich amine liquid using high-grade waste heat resources. The high-grade waste heat resources are the condensate at about 110°C from the reboiling module of the desorption tower 06 of the amine recovery system, that is, the waste heat resource inlet of the high-grade waste heat heating device 05 is connected to the condensate outlet of the reboiling module of the desorption tower 06.

[0092] In the amine recovery system provided in this embodiment, the material inlet of the desorption tower 06, which is connected to the first amine-rich liquid outlet of the three-stage diversion device 13, is located at position D of the desorption tower 06.

[0093] In the amine recovery system provided in this embodiment, the selection of positions A, B, C, and D of the desorption tower 06 is determined by the temperature of the rich amine liquid entering it, and is close to the temperature of the rich amine liquid entering it. Specifically, the temperature at position A of the desorption tower is 105-115% of the temperature of the rich amine liquid after being heated by the low-grade waste heat heating device 14; the temperature at position B of the desorption tower is 95-110% of the temperature of the rich amine liquid after being heated by the medium-grade waste heat heating device 16; the temperature at position C of the desorption tower is 90-100% of the temperature of the rich amine liquid after being heated by the high-grade waste heat heating device 05; and the temperature at position D of the desorption tower is 95-105% of the temperature of the rich amine liquid discharged from the liquid phase outlet of the gas-liquid separation device 18.

[0094] The amine recovery system provided in this embodiment is also equipped with a first rich amine liquid transfer pump 02, which is located at the inlet of the cold fluid flow channel of the first-stage lean rich amine liquid heat exchanger 03.

[0095] The amine recovery system provided in this embodiment is also equipped with a lean liquid cooler 04, which is located at the outlet of the hot fluid flow channel of the primary lean and rich amine liquid heat exchanger 03.

[0096] The amine recovery system provided in this embodiment is also equipped with a second rich amine liquid transfer pump 19, which is located at the liquid phase outlet of the gas-liquid separation device 18 (i.e., the second rich amine liquid transfer pump 19 is located on the connecting pipeline between the liquid phase outlet of the gas-liquid separation device 18 and the rich amine liquid inlet of the three-stage diversion device 13).

[0097] In the amine recovery system provided in this embodiment, the desorption tower 06 is equipped with a tower body 12, a condensation reflux module, and a reboiling module; the condensation reflux module is equipped with a cooler 09, a reflux tank 10, and a reflux pump 11; the material outlet of the cooler 09 is connected to the material inlet of the reflux tank 10, the gas phase outlet of the reflux tank 10 is used for gas discharge, and the liquid phase outlet of the reflux tank 10 is connected to the pump inlet of the reflux pump 11; the reboiling module is equipped with a reboiler 07; the gas phase outlet at the top of the tower body 12 is connected to the cooler 09. The material inlet of the cooler 09 of the condensate reflux module is connected, and the pump outlet of the reflux pump 11 of the condensate reflux module is connected to the liquid phase reflux port at the top of the tower body 12; the liquid phase outlet at the bottom of the tower body 12 is connected to the material inlet of the reboiler 07, and the gas phase material outlet of the reboiler 07 is connected to the gas phase reflux port at the bottom of the tower body 12. The liquid phase material outlet of the reboiler 07 serves as the lean amine liquid outlet of the desorption tower 06 for discharging lean amine liquid; the reboiler 07 is also equipped with a heating steam inlet and a condensate outlet.

[0098] The amine recovery system provided in this embodiment is also equipped with a lean amine liquid transfer pump 08. The lean amine liquid transfer pump 08 is located at the lean amine liquid outlet of the desorption tower 06, that is, the lean amine liquid transfer pump 08 is located on the connecting pipeline between the lean amine liquid outlet of the desorption tower 06 and the inlet of the hot fluid flow channel of the three-stage lean and rich amine liquid heat exchanger 17.

[0099] In the amine recovery system provided in this embodiment, the gas-liquid separation device 18 is a flash tank.

[0100] In the amine recovery system provided in this embodiment, the low-grade waste heat heating device 14, the medium-grade waste heat heating device 16, and the high-grade waste heat heating device 05 all use heat exchangers.

[0101] In the carbon dioxide capture device provided in this embodiment, the cold fluid inlet of the primary lean-rich amine liquid heat exchanger 03 of the amine liquid recovery system is connected to the rich amine liquid outlet of the carbon dioxide absorption tower 01. The hot fluid outlet of the primary lean-rich amine liquid heat exchanger 03 is connected to the organic amine absorbent inlet of the carbon dioxide absorption tower 01. The carbon dioxide absorption tower 01 is also provided with a flue gas inlet and a gas phase outlet.

[0102] The carbon dioxide capture device provided in this embodiment further includes a flue gas pretreatment device 20, which is installed at the flue gas inlet of the carbon dioxide absorption tower 01.

[0103] In the carbon dioxide capture device provided in this embodiment, the outlet of the medium-range waste heat resource of the medium-range waste heat heating device 16 is connected to the flue gas inlet of the carbon dioxide absorption tower 01.

[0104] Comparative Example 3

[0105] This comparative example provides a carbon dioxide capture device.

[0106] The only difference between the carbon dioxide capture device provided in this comparative example and the carbon dioxide capture device provided in Example 2 is that the three-stage lean-rich amine liquid heat exchanger uses the heat exchanger provided in Comparative Example 1.

[0107] Comparative Example 4

[0108] This comparative example provides a carbon dioxide capture device.

[0109] The only difference between the carbon dioxide capture device provided in this comparative example and the carbon dioxide capture device provided in Example 2 is that the three-stage lean and rich amine liquid heat exchanger uses the heat exchanger provided in Comparative Example 2.

[0110] Comparative Example 5

[0111] This comparative example provides a carbon dioxide capture device.

[0112] The carbon dioxide capture device provided in this comparative example adopts the equipment used in the traditional organic amine method for carbon dioxide capture, including a carbon dioxide absorption tower 101, a flue gas pretreatment device 105, and an amine liquid recovery system, the structure of which is as follows: Figure 2 As shown.

[0113] The amine recovery system is equipped with a rich amine liquid transfer pump 102, a lean rich amine liquid heat exchanger 103, a lean liquid cooler 104, a desorption tower 106, and a lean amine liquid transfer pump 108.

[0114] The structure of desorption tower 106 is the same as that of desorption tower 06 used in Example 2. In this comparative example, desorption tower 106 is provided with a tower body 112, a condensation reflux module, and a reboiling module; the condensation reflux module is provided with a cooler 109, a reflux tank 110, and a reflux pump 111. The material outlet of the cooler 109 is connected to the material inlet of the reflux tank 110. The gas phase outlet of the reflux tank 110 is used for gas discharge, and the liquid phase outlet of the reflux tank 110 is connected to the pump inlet of the reflux pump 111; the reboiling module is provided with a reboiler 107; the tower body... The top vapor outlet of tower 112 is connected to the material inlet of cooler 109 of condensation reflux module, and the pump outlet of reflux pump 111 of condensation reflux module is connected to the liquid reflux port at the top of tower 112; the liquid outlet at the bottom of tower 112 is connected to the material inlet of reboiler 107, and the vapor material outlet of reboiler 107 is connected to the vapor reflux port at the bottom of tower 112; the liquid material outlet of reboiler 107 serves as the lean amine liquid outlet of desorption tower 106 for discharging lean amine liquid; reboiler 107 is also provided with heating steam inlet and condensate outlet.

[0115] The structure of the carbon dioxide absorption tower 101 is the same as that of the carbon dioxide absorption tower 01 used in Example 2. The carbon dioxide absorption tower 101 is provided with an amine-rich liquid outlet, an organic amine absorbent inlet, a flue gas inlet, and a gas phase outlet.

[0116] The rich amine liquid outlet of the carbon dioxide absorption tower 101 is connected to the pump inlet of the rich amine liquid transfer pump 102. The pump outlet of the rich amine liquid transfer pump 102 is connected to the cold fluid flow channel inlet of the lean amine liquid heat exchanger 103. The cold fluid flow channel outlet of the lean amine liquid heat exchanger 103 is connected to the material inlet of the desorption tower 106. The lean amine liquid outlet of the desorption tower 106 is connected to the pump inlet of the lean amine liquid transfer pump 108. The pump outlet of the lean amine liquid transfer pump 108 is connected to the hot fluid flow channel inlet of the lean amine liquid heat exchanger 103. The hot fluid flow channel outlet of the lean amine liquid heat exchanger 103 is connected to the material inlet of the lean liquid cooler 104. The material outlet of the lean liquid cooler 104 is connected to the organic amine absorbent inlet of the carbon dioxide absorption tower 101.

[0117] The flue gas pretreatment device 105 is installed at the flue gas inlet of the carbon dioxide absorption tower 101.

[0118] Example 3

[0119] This embodiment provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0120] The amine recovery method provided in this embodiment uses the amine recovery system provided in Example 2, and the carbon dioxide capture method provided in this embodiment uses the carbon dioxide capture device provided in Example 2.

[0121] The carbon dioxide capture method provided in this embodiment includes: S1: A high-efficiency composite amine absorbent at 40℃ and flue gas to be treated at 40℃ after being treated by flue gas pretreatment equipment 20 enter carbon dioxide absorption tower 01. In carbon dioxide absorption tower 01, the high-efficiency composite amine absorbent captures carbon dioxide in the flue gas to be treated to obtain a rich amine liquid. The pressure of carbon dioxide absorption tower 01 is 0.006 MPa; S2: The amine-rich liquid is recovered using the amine recovery method provided in this embodiment to obtain a lean amine liquid; S3: The lean amine solution at around 40℃ obtained in S2 is used as a high-efficiency composite amine absorbent and reintroduced into the carbon dioxide absorption tower 01 to capture carbon dioxide in the flue gas to be treated.

[0122] In this embodiment, the high-efficiency composite amine absorbent has an initial desorption temperature of 70°C for carbon dioxide in the amine-rich solution and a desorption heat of 65 kJ / mol for carbon dioxide in the amine-rich solution. The high-efficiency composite amine absorbent is obtained by mixing the main absorbent hydroxyethyl ethylenediamine, the activation absorption promoter hydroxyethyl piperazine, the regeneration optimizer zinc nitrate, the antioxidant sodium sulfite, and the solvent water in a mass ratio of 25:4:2:1:68.

[0123] The methods for recovering amine solution include: S21: The rich amine liquid obtained in step S1 enters the first-stage lean rich amine liquid heat exchanger 03 and exchanges heat with the lean amine liquid from the second-stage lean rich amine liquid heat exchanger 15 in the first-stage lean rich amine liquid heat exchanger 03 to obtain the first heat-exchanged rich amine liquid; wherein, the temperature of the first heat-exchanged rich amine liquid is 61℃. S22: After the first heat exchange, the rich amine liquid enters the primary diversion device 21 for diversion, resulting in rich amine liquid stream A and rich amine liquid stream B with a mass ratio of 9:1. S23: Rich amine liquid stream A enters the secondary lean rich amine liquid heat exchanger 15, and exchanges heat with the lean amine liquid from the tertiary lean rich amine liquid heat exchanger 17 in the secondary lean rich amine liquid heat exchanger 15 to obtain the second heat-exchanged rich amine liquid; wherein, the temperature of the second heat-exchanged rich amine liquid is 82℃. S24: The rich amine liquid after the second heat exchange enters the secondary diversion device 22 for diversion, and obtains rich amine liquid stream C, rich amine liquid stream D1 and rich amine liquid stream D2 with a mass ratio of 8:1:1. S25: The rich amine liquid stream C enters the three-stage lean rich amine liquid heat exchanger 17, where it exchanges heat and undergoes carbon dioxide desorption with the lean amine liquid from the desorption tower 06, resulting in a rich amine liquid after heat exchange and desorption; wherein, the temperature of the rich amine liquid after heat exchange and desorption is 103℃. S26: The amine-rich liquid after heat exchange and desorption enters the gas-liquid separation device 18 for flash evaporation to achieve gas-liquid separation and obtain gas phase product and liquid phase product; S27: The rich amine liquid stream B enters the low-grade waste heat heating device 14. The low-grade waste heat heating device 14 uses low-grade waste heat resources (hot water at a temperature of about 80°C in the plant area using the amine liquid recovery system) to heat the rich amine liquid stream E. The rich amine liquid stream E enters the desorption tower 06 from position A of the desorption tower 06. Among them, the temperature of the rich amine liquid stream E is 79℃, and the temperature at position A of desorption tower 06 is 84℃. S28: The rich amine liquid stream D1 enters the medium-range waste heat heating device 16, where it is heated using medium-range waste heat resources (flue gas to be treated) to obtain the rich amine liquid stream F. The rich amine liquid stream F enters the desorption tower 06 from position B of the desorption tower 06. Among them, the temperature of the rich amine liquid stream F is 91℃, and the temperature at position B of the desorption tower 06 is 95℃. The flue gas to be treated after being heated in the medium-grade waste heat heating device 16 to process the rich amine liquid stream D1 enters the flue gas pretreatment device 20 for further processing. S29: The rich amine liquid stream D2 enters the desorption tower 06 from the top of the desorption tower 06; S210: The liquid product obtained from the gas-liquid separation device 18 enters the three-stage diversion device 23 for diversion, resulting in amine-rich liquid stream G and amine-rich liquid stream H with a mass ratio of 1:9. Amine-rich liquid stream G enters the high-grade waste heat heating device 05, where it is heated using high-grade waste heat resources (condensate at around 110°C from the reboiling module of the desorption tower 06) to obtain amine-rich liquid stream I. Amine-rich liquid stream I enters the desorption tower 06 from position C. Amine-rich liquid stream H enters the desorption tower 06 from position D. Among them, the temperature of the rich amine liquid stream I is 103℃, and the temperature at position C of desorption tower 06 is 105℃. Among them, the temperature of the rich amine liquid stream H is 101℃, and the temperature at position D of the desorption tower 06 is 104℃. S211: The gaseous product obtained from the gas-liquid separation device 18 enters the desorption tower 06 from the condensation reflux module at the top of the desorption tower 06; S212: The rich amine liquid streams entering the desorption tower 06 undergo carbon dioxide desorption in the desorption tower 06 to obtain lean amine liquid and carbon dioxide gas; Among them, the bottom temperature of desorption tower 06 is 107℃, the top temperature is 86℃, and the pressure of desorption tower is 0.08MPa; S213: The lean amine liquid obtained from the desorption tower 06 flows sequentially through the three-stage lean-rich amine liquid heat exchanger 17, the two-stage lean-rich amine liquid heat exchanger 15, and the first-stage lean-rich amine liquid heat exchanger 03, where it exchanges heat with the rich amine liquid. After heat exchange, the lean amine liquid is cooled by the lean liquid cooler 04 to obtain a lean amine liquid at about 40°C.

[0124] During the amine recovery process, the mass flow rate of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger 03 is 1:0.95 to the mass flow rate of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger 17; the temperature of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger 03 is 41℃; and the temperature of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger 17 is 110℃.

[0125] In this embodiment, steam is used to provide heat (mainly for providing heat energy for the desorption of carbon dioxide from the amine-rich liquid in the desorption tower 06), and cooling is achieved using cooling water at around 35°C (mainly for cooling in the condensation reflux module at the top of the desorption tower 06 and in the lean liquid cooler 04, as well as the absorption tower top water washing circulation cooling module and the flue gas cooling system).

[0126] The data of the flue gas to be treated used in this embodiment are shown in Table 1.

[0127] In this embodiment, when the circulating load is 25 liters of CO2 / liter of absorbent (i.e., each liter of absorbent carries 25 liters of carbon dioxide once it circulates between the absorption tower and the regeneration tower), the steam consumption of the desorption tower 06 is 1.0 ton / ton of CO2 (i.e., 1.0 ton of steam is consumed for each ton of carbon dioxide processed), and the circulating cooling water consumption (around 35°C) is 110 ton / ton of CO2 (i.e., 110 ton of circulating cooling water is consumed for each ton of carbon dioxide processed).

[0128] In this embodiment, the CO2 desorption capacity in the three-stage lean-rich amine liquid heat exchanger 17 is 35g / L of rich amine liquid (i.e., 35g of carbon dioxide is desorbed per liter of rich amine liquid). After the rich amine liquid is treated by the three-stage lean-rich amine liquid heat exchanger 17, it enters the gas-liquid separation device 18 for gas-liquid separation, and the carbon dioxide loading in the liquid phase product is 25g / L of amine liquid.

[0129] Table 1

[0130] Comparative Example 6

[0131] This comparative example provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0132] The difference between the amine recovery method and carbon dioxide capture method provided in this comparative example and the amine recovery method and carbon dioxide capture method provided in Example 3 is only that the carbon dioxide capture device provided in Comparative Example 3 is used. That is, the inner wall surface of the cold fluid flow channel of the three-stage lean and rich amine liquid heat exchanger is not coated and is still a conventional stainless steel smooth surface.

[0133] In this comparative example, when the circulating load is 25 liters of CO2 / liter of absorbent (i.e., each liter of absorbent carries 25 liters of carbon dioxide once it circulates between the absorption tower and the regeneration tower), the steam consumption of desorption tower 06 is 1.1 tons / ton of CO2 (i.e., 1.1 tons of steam are consumed per ton of carbon dioxide processed), and the circulating cooling water consumption (around 35 degrees Celsius) is 115 tons / ton of CO2 (i.e., 115 tons of circulating cooling water are consumed per ton of carbon dioxide processed).

[0134] In this comparative example, the temperature of the rich amine liquid after heat exchange and desorption in the three-stage lean-rich amine liquid heat exchanger is 105℃, the CO2 desorption capacity in the three-stage lean-rich amine liquid heat exchanger is 15g / L of rich amine liquid (i.e., 15g of carbon dioxide is desorbed per liter of rich amine liquid), and the carbon dioxide loading in the liquid phase product after the rich amine liquid treated by the three-stage lean-rich amine liquid heat exchanger enters the gas-liquid separation equipment for gas-liquid separation is 30g / L of amine liquid.

[0135] Comparative Example 7

[0136] This comparative example provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0137] The difference between the amine recovery method and carbon dioxide capture method provided in this comparative example and the amine recovery method and carbon dioxide capture method provided in Example 3 is that the carbon dioxide capture device provided in Comparative Example 4 is used. That is, the coating on the inner wall surface of the cold fluid flow channel of the three-stage lean and rich amine liquid heat exchanger is a polytetrafluoroethylene (PTFE) anti-corrosion coating. The surface of this coating is smooth and does not have catalytic activity.

[0138] In this comparative example, under the same amine liquid circulation rate as in Example 3, the steam consumption of desorption tower 06 is 1.1 tons / ton CO2 (i.e., 1.1 tons of steam are consumed per ton of carbon dioxide processed), and the circulating cooling water consumption (around 35 degrees Celsius) is 115 tons / ton CO2 (i.e., 115 tons of circulating cooling water are consumed per ton of carbon dioxide processed).

[0139] In this comparative example, the temperature of the rich amine liquid after heat exchange and desorption in the three-stage lean-rich amine liquid heat exchanger is 107℃, the CO2 desorption capacity in the three-stage lean-rich amine liquid heat exchanger is 15g / L of rich amine liquid (i.e., 15g of carbon dioxide is desorbed per liter of rich amine liquid), and after the rich amine liquid treated by the three-stage lean-rich amine liquid heat exchanger enters the gas-liquid separation equipment for gas-liquid separation, the carbon dioxide loading in the liquid phase product is 30g / L of amine liquid.

[0140] As can be seen from Examples 3, 6, and 7, when the rich amine liquid vaporization heat exchanger provided by this invention is used as a three-stage lean amine liquid heat exchanger (i.e., when the inner wall surface of the cold fluid flow channel of the three-stage lean amine liquid heat exchanger is coated with a special coating), compared with the use of a conventional heat exchanger as a three-stage lean amine liquid heat exchanger (i.e., when the inner wall surface of the cold fluid flow channel of the three-stage lean amine liquid heat exchanger is not coated or is only coated with an anti-corrosion coating), on the one hand, the CO2 desorption capacity is significantly increased, exceeding 100%, and the carbon dioxide loading of the desorbed liquid phase product is very low, meaning that most of the carbon dioxide has been desorbed; on the other hand, the temperature of the desorbed rich amine liquid is low, indicating that the rich amine liquid vaporization heat exchanger provided by this invention effectively reduces the energy barrier of the desorption reaction through the special coating, allowing CO2 to be released in large quantities at a lower temperature, which helps to reduce the demand for high-quality heat sources and achieve energy saving. In summary, the amine-rich liquid vaporization heat exchanger provided by this invention achieves synergistic effects of "catalysis" and "nucleation" through a unique coating design. This allows the amine-rich liquid to fully utilize the thermal energy of the hot fluid to achieve efficient carbon dioxide desorption, significantly reducing the load on the regeneration tower and the regeneration energy consumption of the entire carbon capture system. It has extremely high industrial application value.

[0141] Comparative Example 8

[0142] This comparative example provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0143] The amine recovery method provided in this comparative example uses the amine recovery system provided in Example 2, and the carbon dioxide capture method provided in this comparative example uses the carbon dioxide capture device provided in Example 2.

[0144] The carbon dioxide capture method provided in this comparative example includes: A1: A traditional organic amine absorbent at around 40°C and flue gas to be treated at around 40°C after being treated by flue gas pretreatment equipment 20 enter carbon dioxide absorption tower 01. In carbon dioxide absorption tower 01, the traditional organic amine absorbent captures carbon dioxide in the flue gas to be treated, and a rich amine liquid is obtained. The pressure of carbon dioxide absorption tower 01 is 0.006 MPa; A2: The amine-rich solution was recovered using the amine recovery method provided in this comparative example to obtain a lean amine solution; A3: The lean amine solution at around 40°C obtained in A2 is used as a traditional organic amine absorbent and reintroduced into the carbon dioxide absorption tower 01 to capture carbon dioxide in the flue gas to be treated.

[0145] In this comparative example, the initial desorption temperature of carbon dioxide in the amine-rich liquid of the conventional organic amine absorbent used was 89℃, and the desorption heat of carbon dioxide in the amine-rich liquid was 97kJ / mol. This conventional organic amine absorbent was obtained by mixing the main absorbent piperazine and the solvent water in a mass ratio of 3:7.

[0146] The methods for recovering amine solution include: A21: The rich amine liquid obtained in step A1 enters the first-stage lean rich amine liquid heat exchanger 03 and exchanges heat with the lean amine liquid from the second-stage lean rich amine liquid heat exchanger 15 in the first-stage lean rich amine liquid heat exchanger 03 to obtain the first heat-exchanged rich amine liquid; wherein, the temperature of the first heat-exchanged rich amine liquid is 53℃. A22: After the first heat exchange, the rich amine liquid enters the primary diversion device 21 for diversion, resulting in rich amine liquid stream A and rich amine liquid stream B with a mass ratio of 9:1. A23: Rich amine liquid stream A enters the secondary lean rich amine liquid heat exchanger 15, and exchanges heat with the lean amine liquid from the tertiary lean rich amine liquid heat exchanger 17 in the secondary lean rich amine liquid heat exchanger 15 to obtain the second heat-exchanged rich amine liquid; wherein, the temperature of the second heat-exchanged rich amine liquid is 80℃. A24: The rich amine liquid after the second heat exchange enters the secondary diversion device 22 for diversion, resulting in rich amine liquid stream C, rich amine liquid stream D1 and rich amine liquid stream D2 with a mass ratio of 8:1:1. A25: The rich amine liquid stream C enters the three-stage lean rich amine liquid heat exchanger 17, where it exchanges heat and undergoes carbon dioxide desorption with the lean amine liquid from the desorption tower 06, resulting in a rich amine liquid after heat exchange and desorption; wherein, the temperature of the rich amine liquid after heat exchange and desorption is 97℃. A26: The amine-rich liquid after heat exchange and desorption enters the gas-liquid separation device 18 for flash evaporation to achieve gas-liquid separation and obtain gas phase product and liquid phase product; A27: The rich amine liquid stream B enters the low-grade waste heat heating device 14. The low-grade waste heat heating device 14 uses low-grade waste heat resources (hot water at a temperature of about 80°C in the plant area using the amine liquid recovery system) to heat the rich amine liquid stream E. The rich amine liquid stream E enters the desorption tower 06 from position A of the desorption tower 06. Among them, the temperature of the rich amine liquid stream E is 75℃, and the temperature at position A of the desorption tower 06 is 80℃. A28: The rich amine liquid stream D1 enters the medium-range waste heat heating device 16, where it is heated using medium-range waste heat resources (flue gas to be treated) to obtain the rich amine liquid stream F. The rich amine liquid stream F enters the desorption tower 06 from position B of the desorption tower 06. Among them, the temperature of the rich amine liquid stream F is 85℃, and the temperature at position B of the desorption tower 06 is 86℃. The flue gas to be treated after being heated in the medium-grade waste heat heating device 16 to process the rich amine liquid stream D1 enters the flue gas pretreatment device 20 for further processing. A29: The rich amine liquid stream D2 enters the desorption tower 06 from the top of the desorption tower 06; A210: The liquid product obtained from the gas-liquid separation device 18 enters the three-stage diversion device 23 for diversion, resulting in amine-rich liquid stream G and amine-rich liquid stream H with a mass ratio of 1:9. Amine-rich liquid stream G enters the high-grade waste heat heating device 05, where it is heated using high-grade waste heat resources (condensate at around 110°C from the reboiling module of the desorption tower 06) to obtain amine-rich liquid stream I. Amine-rich liquid stream I enters the desorption tower 06 from position C. Amine-rich liquid stream H enters the desorption tower 06 from position D. Among them, the temperature of the rich amine liquid stream I is 100℃, and the temperature at position C of the desorption tower 06 is 95℃; Among them, the temperature of the rich amine liquid stream H is 97℃, and the temperature at position D of the desorption tower 06 is 96℃. A211: The gaseous product obtained from the gas-liquid separation device 18 enters the desorption tower 06 from the condensation reflux module at the top of the desorption tower 06; A212: The rich amine liquid streams entering the desorption tower 06 undergo carbon dioxide desorption in the desorption tower 06 to obtain lean amine liquid and carbon dioxide gas; Among them, the bottom temperature of desorption tower 06 is 110℃, the top temperature is 88℃, and the pressure of the desorption tower is 0.04MPa. A213: The lean amine liquid obtained from the desorption tower 06 flows sequentially through the three-stage lean-rich amine liquid heat exchanger 17, the two-stage lean-rich amine liquid heat exchanger 15, and the first-stage lean-rich amine liquid heat exchanger 03, where it exchanges heat with the rich amine liquid. After heat exchange, the lean amine liquid is cooled by the lean liquid cooler 04 to obtain a lean amine liquid at about 40°C.

[0147] During the amine recovery process, the mass flow rate of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger 03 is 1:0.97 to the mass flow rate of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger 17; the temperature of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger 03 is 53℃; and the temperature of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger 17 is 110℃.

[0148] In this comparative example, steam is used to provide heat (mainly to provide heat energy for the desorption of carbon dioxide from the amine-rich liquid in desorption tower 06), and cooling water at around 35°C is used for cooling (mainly for cooling in the condensation reflux module at the top of desorption tower 06 and in the lean liquid cooler 04).

[0149] The data of the flue gas to be treated used in this comparative example are shown in Table 1.

[0150] In this comparative example, under the premise of achieving the same production capacity and capture rate as in Example 3, the steam consumption of desorption tower 06 is 1.95 tons / ton CO2 (i.e., 1.95 tons of steam are consumed per ton of carbon dioxide processed), and the circulating cooling water consumption (around 35°C) is 148.7 tons / ton CO2 (i.e., 148.7 tons of circulating cooling water are consumed per ton of carbon dioxide processed).

[0151] Comparative Example 9

[0152] This comparative example provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0153] The amine recovery method provided in this comparative example uses the amine recovery system provided in Comparative Example 5, and the carbon dioxide capture method provided in this comparative example uses the carbon dioxide capture device provided in Comparative Example 5.

[0154] The carbon dioxide capture method provided in this comparative example includes: B1: A traditional organic amine absorbent at around 40°C and flue gas to be treated at around 40°C after being treated by flue gas pretreatment equipment 20 enter carbon dioxide absorption tower 101. In carbon dioxide absorption tower 101, the traditional organic amine absorbent captures carbon dioxide in the flue gas to be treated, and a rich amine liquid is obtained. The pressure of the carbon dioxide absorption tower 101 is 0.006 MPa; B2: The amine-rich solution is recovered using the amine recovery method provided in this comparative example to obtain a lean amine solution; B3: The lean amine solution at around 40°C obtained from B2 is used as a traditional organic amine absorbent and reintroduced into the carbon dioxide absorption tower 101 to capture carbon dioxide in the flue gas to be treated.

[0155] In this comparative example, the initial desorption temperature of carbon dioxide in the amine-rich liquid of the conventional organic amine absorbent used was 89℃, and the desorption heat of carbon dioxide in the amine-rich liquid was 97kJ / mol. This conventional organic amine absorbent was obtained by mixing the main absorbent piperazine and the solvent water in a mass ratio of 3:7.

[0156] The methods for recovering amine solution include: B21: The rich amine liquid obtained in step B1 enters the lean amine liquid heat exchanger 103 and exchanges heat with the lean amine liquid from the desorption tower 106 in the lean amine liquid heat exchanger 103 to obtain the rich amine liquid after heat exchange; wherein, the temperature of the rich amine liquid after heat exchange is 53℃. B22: The heat-exchanged rich amine solution enters the desorption tower 106 from position A of the desorption tower 106; The temperature of the amine-rich liquid after heat exchange is 97℃, and the temperature at position A of the desorption tower 106 is 96℃. B23: The amine-rich liquid entering the desorption tower 106 undergoes carbon dioxide desorption in the desorption tower 106 to obtain amine-lean liquid and carbon dioxide gas; Among them, the bottom temperature of desorption tower 06 is 110℃, the top temperature is 88℃, and the pressure of desorption tower is 0.04MPa; B24: The lean amine solution obtained from the desorption tower 106 enters the lean-rich amine solution heat exchanger 103, where it exchanges heat with the rich amine solution. After heat exchange, the lean amine solution is cooled by the lean solution cooler 104 to obtain a lean amine solution at about 40°C.

[0157] During the amine recovery process, the mass flow rate of the rich amine liquid entering the lean amine liquid heat exchanger 103 is 1:0.97 to the mass flow rate of the lean amine liquid entering the lean amine liquid heat exchanger 103; the temperature of the rich amine liquid entering the lean amine liquid heat exchanger 103 is 53℃; and the temperature of the lean amine liquid entering the lean amine liquid heat exchanger 103 is 110℃.

[0158] In this comparative example, steam is used to provide heat (mainly for providing heat energy for the desorption of carbon dioxide from the amine-rich liquid in the desorption tower 106), and cooling is achieved using cooling water at around 35°C (mainly for cooling in the condensation reflux module at the top of the desorption tower 106, cooling in the lean liquid cooler 104, and water washing circulation cooling at the top of the absorption tower and for flue gas cooling).

[0159] The data of the flue gas to be treated used in this comparative example are shown in Table 1.

[0160] In this comparative example, under the same circulating flow rate as Comparative Example 8, the steam consumption of desorption tower 06 is 2.08 tons / ton CO2 (i.e., 2.08 tons of steam are consumed per ton of carbon dioxide processed), and the circulating cooling water consumption (around 35°C) is 136.9 tons / ton CO2 (i.e., 136.9 tons of circulating cooling water are consumed per ton of carbon dioxide processed).

[0161] Comparative Example 10

[0162] This comparative example provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0163] The amine recovery method provided in this comparative example uses the amine recovery system provided in Comparative Example 5, and the carbon dioxide capture method provided in this comparative example uses the carbon dioxide capture device provided in Comparative Example 5.

[0164] The carbon dioxide capture method provided in this comparative example includes: C1: A high-efficiency composite amine absorbent at around 40°C, and flue gas to be treated at around 40°C after being treated by flue gas pretreatment equipment 20, enters carbon dioxide absorption tower 101. In carbon dioxide absorption tower 101, the high-efficiency composite amine absorbent captures carbon dioxide in the flue gas to be treated, and a rich amine liquid is obtained. The pressure of the carbon dioxide absorption tower 101 is 0.006 MPa; C2: The amine-rich solution is recovered using the amine recovery method provided in this comparative example to obtain a lean amine solution; C3: The lean amine solution at around 40°C obtained from C2 is used as a highly efficient composite amine absorbent and reintroduced into the carbon dioxide absorption tower 101 to capture carbon dioxide in the flue gas to be treated.

[0165] In this comparative example, the initial desorption temperature of carbon dioxide in the amine-rich liquid of the high-efficiency composite amine absorbent is 70℃, and the desorption heat of carbon dioxide in the amine-rich liquid is 65kJ / mol. The high-efficiency composite amine absorbent is obtained by mixing the main absorbent hydroxyethyl ethylenediamine, the activation absorption promoter hydroxyethyl piperazine, the regeneration optimizer zinc nitrate, the antioxidant sodium sulfite, and the solvent water in a mass ratio of 25:4:2:1:68.

[0166] The methods for recovering amine solution include: C21: The rich amine liquid obtained in step C1 enters the lean amine liquid heat exchanger 103 and exchanges heat with the lean amine liquid from the desorption tower 106 in the lean amine liquid heat exchanger 103 to obtain the rich amine liquid after heat exchange; wherein, the temperature of the rich amine liquid after heat exchange is 100℃. C22: The amine-rich liquid after heat exchange enters the desorption tower 106 from position A of the desorption tower 106; The temperature of the amine-rich liquid after heat exchange is 100℃, and the temperature at position A of the desorption tower 106 is 98℃. C23: The amine-rich liquid entering the desorption tower 106 undergoes carbon dioxide desorption in the desorption tower 106 to obtain amine-lean liquid and carbon dioxide gas; Among them, the bottom temperature of desorption tower 06 is 108℃, the top temperature is 85℃, and the pressure of desorption tower is 0.08MPa; C24: The lean amine solution obtained from the desorption tower 106 enters the lean-rich amine solution heat exchanger 103, where it exchanges heat with the rich amine solution. After heat exchange, the lean amine solution is cooled by the lean solution cooler 104 to obtain a lean amine solution at about 40°C.

[0167] During the amine recovery process, the mass flow rate of the rich amine liquid entering the lean-rich amine liquid heat exchanger 103 is 1:0.95 to the mass flow rate of the lean amine liquid entering the lean-rich amine liquid heat exchanger 103; the temperature of the rich amine liquid entering the lean-rich amine liquid heat exchanger 103 is 50℃; and the temperature of the lean amine liquid entering the lean-rich amine liquid heat exchanger 103 is 108℃.

[0168] In this comparative example, steam is used to provide heat (mainly for providing heat energy for the desorption of carbon dioxide from the amine-rich liquid in the desorption tower 106), and cooling water at around 35°C is used for cooling (mainly for cooling in the condensation reflux module at the top of the desorption tower 106 and for cooling in the lean liquid cooler 104).

[0169] The data of the flue gas to be treated used in this comparative example are shown in Table 1.

[0170] In this comparative example, under the same circulation flow rate as Comparative Example 5, the steam consumption of desorption tower 06 is 1.3 tons / ton CO2 (i.e., 1.3 tons of steam are consumed per ton of carbon dioxide processed), and the circulating cooling water consumption (around 35°C) is 118 tons / ton CO2 (i.e., 118 tons of circulating cooling water are consumed per ton of carbon dioxide processed).

[0171] As can be seen from Examples 3, 8, 9 and 10, the amine liquid recovery method and carbon dioxide capture method provided by the present invention significantly reduce heat consumption and circulating water consumption compared with the traditional organic amine carbon dioxide capture process.

[0172] Example 4

[0173] This embodiment provides a method for amine liquid recovery and a method for carbon dioxide capture.

[0174] The amine recovery method provided in this embodiment uses the amine recovery system provided in Example 2, and the carbon dioxide capture method provided in this embodiment uses the carbon dioxide capture device provided in Example 2.

[0175] The carbon dioxide capture method provided in this embodiment includes: S1: A high-efficiency composite amine absorbent at 40℃ and flue gas to be treated at 40℃ after being treated by flue gas pretreatment equipment 20 enter carbon dioxide absorption tower 01. In carbon dioxide absorption tower 01, the high-efficiency composite amine absorbent captures carbon dioxide in the flue gas to be treated to obtain a rich amine liquid. The pressure of carbon dioxide absorption tower 01 is 0.006 MPa; S2: The amine-rich liquid is recovered using the amine recovery method provided in this embodiment to obtain a lean amine liquid; S3: The lean amine solution at around 40℃ obtained in S2 is used as a high-efficiency composite amine absorbent and reintroduced into the carbon dioxide absorption tower 01 to capture carbon dioxide in the flue gas to be treated.

[0176] In this embodiment, the high-efficiency composite amine absorbent has an initial desorption temperature of 70°C for carbon dioxide in the amine-rich solution and a desorption heat of 65 kJ / mol for carbon dioxide in the amine-rich solution. The high-efficiency composite amine absorbent is obtained by mixing the main absorbent hydroxyethyl ethylenediamine, the activation absorption promoter hydroxyethyl piperazine, the regeneration optimizer zinc nitrate, the antioxidant sodium sulfite, and the solvent water in a mass ratio of 25:4:2:1:68.

[0177] The methods for recovering amine solution include: S21: The rich amine liquid obtained in step S1 enters the first-stage lean rich amine liquid heat exchanger 03 and exchanges heat with the lean amine liquid from the second-stage lean rich amine liquid heat exchanger 15 in the first-stage lean rich amine liquid heat exchanger 03 to obtain the first heat-exchanged rich amine liquid; wherein, the temperature of the first heat-exchanged rich amine liquid is 61℃. S22: After the first heat exchange, the rich amine liquid enters the primary diversion device 21 for diversion, resulting in rich amine liquid stream A and rich amine liquid stream B with a mass ratio of 9:1. S23: Rich amine liquid stream A enters the secondary lean rich amine liquid heat exchanger 15, and exchanges heat with the lean amine liquid from the tertiary lean rich amine liquid heat exchanger 17 in the secondary lean rich amine liquid heat exchanger 15 to obtain the second heat-exchanged rich amine liquid; wherein, the temperature of the second heat-exchanged rich amine liquid is 82℃. S24: The rich amine liquid after the second heat exchange enters the secondary diversion device 22 for diversion, and obtains rich amine liquid stream C, rich amine liquid stream D1 and rich amine liquid stream D2 with a mass ratio of 8:1:1. S25: The rich amine liquid stream C enters the three-stage lean rich amine liquid heat exchanger 17, where it exchanges heat and undergoes carbon dioxide desorption with the lean amine liquid from the desorption tower 06, resulting in a rich amine liquid after heat exchange and desorption; wherein, the temperature of the rich amine liquid after heat exchange and desorption is 103℃. S26: The amine-rich liquid after heat exchange and desorption enters the gas-liquid separation device 18 for flash evaporation to achieve gas-liquid separation and obtain gas phase product and liquid phase product; S27: The rich amine liquid stream B enters the low-grade waste heat heating device 14. The low-grade waste heat heating device 14 uses low-grade waste heat resources (hot water at a temperature of about 80°C in the plant area using the amine liquid recovery system) to heat the rich amine liquid stream E. The rich amine liquid stream E enters the desorption tower 06 from position A of the desorption tower 06. Among them, the temperature of the rich amine liquid stream E is 79℃, and the temperature at position A of desorption tower 06 is 84℃. S28: The rich amine liquid stream D1 enters the medium-range waste heat heating device 16, where it is heated using medium-range waste heat resources (flue gas to be treated) to obtain the rich amine liquid stream F. The rich amine liquid stream F enters the desorption tower 06 from position B of the desorption tower 06. Among them, the temperature of the rich amine liquid stream F is 95℃, and the temperature at position B of the desorption tower 06 is 95℃. The flue gas to be treated after being heated in the medium-grade waste heat heating device 16 to process the rich amine liquid stream D1 enters the flue gas pretreatment device 20 for further processing. S29: The rich amine liquid stream D2 enters the desorption tower 06 from the top of the desorption tower 06; S210: The liquid product obtained from the gas-liquid separation device 18 enters the three-stage diversion device 23 for diversion, resulting in amine-rich liquid stream G and amine-rich liquid stream H with a mass ratio of 1:9. Amine-rich liquid stream G enters the high-grade waste heat heating device 05, where it is heated using high-grade waste heat resources (condensate at around 110°C from the reboiling module of the desorption tower 06) to obtain amine-rich liquid stream I. Amine-rich liquid stream I enters the desorption tower 06 from position C. Amine-rich liquid stream H enters the desorption tower 06 from position D. Among them, the temperature of the rich amine liquid stream I is 103℃, and the temperature at position C of desorption tower 06 is 105℃. Among them, the temperature of the rich amine liquid stream H is 101℃, and the temperature at position D of the desorption tower 06 is 104℃. S211: The gaseous product obtained from the gas-liquid separation device 18 enters the desorption tower 06 from the condensation reflux module at the top of the desorption tower 06; S212: The rich amine liquid streams entering the desorption tower 06 undergo carbon dioxide desorption in the desorption tower 06 to obtain lean amine liquid and carbon dioxide gas; Among them, the bottom temperature of desorption tower 06 is 107℃, the top temperature is 86℃, and the pressure of desorption tower is 0.08MPa; S213: The lean amine liquid obtained from the desorption tower 06 flows sequentially through the three-stage lean-rich amine liquid heat exchanger 17, the two-stage lean-rich amine liquid heat exchanger 15, and the first-stage lean-rich amine liquid heat exchanger 03, where it exchanges heat with the rich amine liquid. After heat exchange, the lean amine liquid is cooled by the lean liquid cooler 04 to obtain a lean amine liquid at about 40°C.

[0178] During the amine recovery process, the mass flow rate of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger 03 is 1:0.95 to the mass flow rate of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger 17; the temperature of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger 03 is 41℃; and the temperature of the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger 17 is 110℃.

[0179] In this embodiment, steam is used to provide heat (mainly for providing heat energy for the desorption of carbon dioxide from the amine-rich liquid in the desorption tower 06), and cooling is achieved using cooling water at around 35°C (mainly for cooling in the condensation reflux module at the top of the desorption tower 06 and in the lean liquid cooler 04, as well as the absorption tower top water washing circulation cooling module and the flue gas cooling system).

[0180] The data of the flue gas to be treated used in this embodiment are shown in Table 1.

[0181] In this embodiment, when the circulating load is 32 liters of CO2 / liter of absorbent (i.e., each liter of absorbent carries 32 liters of carbon dioxide once it circulates between the absorption tower and the regeneration tower), the steam consumption of the desorption tower 06 is 0.9 tons / ton of CO2 (i.e., 0.9 tons of steam are consumed per ton of carbon dioxide processed), and the circulating cooling water consumption (around 35°C) is 105 tons / ton of CO2 (i.e., 105 tons of circulating cooling water are consumed per ton of carbon dioxide processed).

[0182] In this embodiment, the CO2 desorption capacity in the three-stage lean-rich amine liquid heat exchanger 17 is 38 g / L of rich amine liquid (i.e., 38 g of carbon dioxide is desorbed per liter of rich amine liquid). After the rich amine liquid is treated by the three-stage lean-rich amine liquid heat exchanger 17, it enters the gas-liquid separation device 18 for gas-liquid separation, and the carbon dioxide loading in the liquid phase product is 22 g / L of amine liquid.

[0183] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rich amine liquid vaporization heat exchanger, characterized in that, The inner wall surface of the cold fluid flow channel of the amine-rich liquid vaporization heat exchanger is coated with a coating; the coating includes a base material and an active catalytic component supported on the base material; The matrix material is capable of enabling carbon dioxide bubble nucleation; The active catalytic component can reduce the activation energy of the carbon dioxide desorption reaction of the amine-rich liquid obtained after the organic amine absorbent absorbs carbon dioxide.

2. The amine-rich liquid vaporization heat exchanger according to claim 1, characterized in that, The surface roughness Ra of the coating is 5-50 micrometers.

3. The amine-rich liquid vaporization heat exchanger according to claim 1, characterized in that, The matrix material is selected from porous ceramic materials and / or polymer materials; and / or The active catalytic component is selected from at least one of metal oxides and solid acids.

4. The amine-rich liquid vaporization heat exchanger according to claim 3, characterized in that, The matrix material is selected from one or more combinations of silicon carbide foam ceramic materials, alumina foam ceramic materials, and polytetrafluoroethylene materials; and / or The metal oxide is selected from one or more of nano-titanium dioxide, nano-zirconium oxide, and nano-alumina; and / or The solid acid is selected from one or more of the following molecular sieves: HZSM-5, H-Beta, and HY.

5. The amine-rich liquid vaporization heat exchanger according to claim 1, characterized in that, The content of active catalytic components is 5-15% based on the total mass of the matrix material (100%).

6. An amine liquid recovery system, characterized in that, The amine recovery system is equipped with a primary amine liquid heat exchanger (for lean and rich amine liquids), a primary diversion device, a secondary amine liquid heat exchanger (for lean and rich amine liquids), a tertiary amine liquid heat exchanger (for lean and rich amine liquids), a gas-liquid separation device, and a desorption tower. The three-stage lean-rich amine liquid heat exchanger is the amine liquid vaporization heat exchanger according to any one of claims 1-5. The cold fluid inlet of the primary lean-rich amine liquid heat exchanger is connected to the rich amine liquid outlet of the carbon dioxide absorption tower; the cold fluid inlet of the primary lean-rich amine liquid heat exchanger is connected to the rich amine liquid inlet of the primary diversion device; the first rich amine liquid outlet of the primary diversion device is connected to the cold fluid inlet of the secondary lean-rich amine liquid heat exchanger; the cold fluid inlet of the secondary lean-rich amine liquid heat exchanger is connected to the rich amine liquid inlet of the secondary diversion device; the first rich amine liquid outlet of the secondary diversion device is connected to the cold fluid inlet of the tertiary lean-rich amine liquid heat exchanger; the cold fluid inlet of the tertiary lean-rich amine liquid heat exchanger is connected to the material inlet of the gas-liquid separation device; and the liquid phase outlet of the gas-liquid separation device is connected to the material inlet of the desorption tower. The desorption tower's lean amine liquid outlet is connected to the inlet of the hot fluid flow channel of the tertiary lean-rich amine liquid heat exchanger; the tertiary lean-rich amine liquid heat exchanger's hot fluid flow channel outlet is connected to the inlet of the secondary lean-rich amine liquid heat exchanger; the secondary lean-rich amine liquid heat exchanger's hot fluid flow channel outlet is connected to the inlet of the primary lean-rich amine liquid heat exchanger; and the primary lean-rich amine liquid heat exchanger's hot fluid flow channel outlet is used to connect to the organic amine absorbent inlet of the carbon dioxide absorption tower. The primary diversion device, except for the first rich amine liquid outlet, has its other rich amine liquid outlets connected to the material inlet of the desorption tower; the secondary diversion device, except for the first rich amine liquid outlet, has its other rich amine liquid outlets connected to the material inlet of the desorption tower.

7. The amine recovery system according to claim 6, characterized in that, The amine recovery system also includes a low-grade waste heat heating device. This device is installed on the connecting pipeline between the second rich amine liquid outlet of the primary diversion device and the material inlet of the desorption tower. The low-grade waste heat heating device is used to heat the rich amine liquid using low-grade waste heat resources; wherein, the low-grade waste heat resources refer to waste heat resources with a temperature of 75-85℃; and / or The amine recovery system also includes a medium-range waste heat heating device. This device is installed on the connecting pipeline between the second rich amine liquid outlet of the secondary diversion device and the material inlet of the desorption tower. The medium-range waste heat heating device is used to heat the rich amine liquid using medium-range waste heat resources; wherein, the medium-range waste heat resources refer to waste heat resources with a temperature of 85-95℃; and / or The amine recovery system also includes a three-stage diversion device and a high-grade waste heat heating device. The three-stage diversion device and the high-grade waste heat heating device are sequentially connected on the pipeline between the liquid phase outlet of the gas-liquid separator and the material inlet of the desorption tower. Specifically, the liquid phase outlet of the gas-liquid separator is connected to the rich amine inlet of the three-stage diversion device, the first rich amine outlet of the three-stage diversion device is connected to the material inlet of the desorption tower, the second rich amine outlet of the three-stage diversion device is connected to the material inlet of the high-grade waste heat heating device, and the material outlet of the high-grade waste heat heating device is connected to the material inlet of the desorption tower. The high-grade waste heat resource refers to waste heat resources with a temperature of 105-115℃.

8. The amine recovery system according to claim 7, characterized in that, The material inlet of the desorption tower connected to the second amine-rich liquid outlet of the primary diversion device is located at position A of the desorption tower, and the temperature at position A of the desorption tower is 105-115% of the temperature of the amine-rich liquid after being heated by the low-grade waste heat heating equipment; and / or The material inlet of the desorption tower connected to the second amine-rich liquid outlet of the secondary diversion device is located at position B of the desorption tower, and the temperature at position B of the desorption tower is 95-110% of the temperature of the amine-rich liquid after being heated by the medium-range waste heat heating equipment; and / or The material inlet of the desorption tower connected to the outlet of the second amine-rich liquid in the three-stage diversion device is located at position C of the desorption tower, and the temperature at position C is 90-100% of the temperature of the amine-rich liquid after being heated by the high-grade waste heat heating equipment; and / or The material inlet of the desorption tower connected to the first amine-rich liquid outlet of the three-stage diversion device is located at position D of the desorption tower, and the temperature at position D of the desorption tower is 95-105% of the temperature of the amine-rich liquid discharged from the liquid phase outlet of the gas-liquid separation device.

9. The amine recovery system according to claim 6, characterized in that, The material inlet of the desorption tower, which is connected to the third amine-rich liquid outlet of the secondary diversion device, is located at the top of the desorption tower.

10. The amine recovery system according to claim 6, characterized in that, The gas phase outlet of the gas-liquid separation device is connected to the material inlet of the desorption tower.

11. The amine recovery system according to claim 10, characterized in that, The material inlet of the desorption tower, which is connected to the gas phase outlet of the gas-liquid separation equipment, is located on the condensation reflux module at the top of the desorption tower.

12. A method for recovering amine liquid, characterized in that, The amine recovery method is performed using the amine recovery system according to any one of claims 6-11, and the amine recovery method includes: The amine-rich liquid obtained by capturing carbon dioxide using a high-efficiency composite amine absorbent enters a first-stage amine-lean heat exchanger, where it exchanges heat with the amine-lean liquid from a second-stage amine-lean heat exchanger to obtain the first post-heat exchange amine-rich liquid; wherein, the temperature of the first post-heat exchange amine-rich liquid is 80-85% of the initial carbon dioxide desorption temperature of the amine-rich liquid. After the first heat exchange, the rich amine liquid enters the first-stage diversion device for diversion, resulting in rich amine liquid stream A and the remaining rich amine liquid stream other than rich amine liquid stream A, i.e., rich amine liquid stream B. Amine-rich liquid stream A enters a secondary lean amine-rich liquid heat exchanger, where it exchanges heat with the lean amine liquid from the tertiary lean amine-rich liquid heat exchanger to obtain a second heat-exchanged amine-rich liquid; wherein, the temperature of the second heat-exchanged amine-rich liquid is 105-120% of the initial carbon dioxide desorption temperature of the amine-rich liquid. After the second heat exchange, the rich amine liquid enters the secondary diversion device for diversion, resulting in rich amine liquid stream C and the remaining rich amine liquid stream D excluding rich amine liquid stream C. The rich amine liquid stream C enters the three-stage lean rich amine liquid heat exchanger, where it exchanges heat and undergoes carbon dioxide desorption with the lean amine liquid from the desorption tower, resulting in a rich amine liquid after heat exchange and desorption; wherein, the temperature of the rich amine liquid after heat exchange and desorption is 125% or more of the initial carbon dioxide desorption temperature of the rich amine liquid. After heat exchange and desorption, the amine-rich liquid enters a gas-liquid separation device for gas-liquid separation to obtain gaseous and liquid products. The rich amine liquid stream B, the rich amine liquid stream D, and the liquid phase product obtained from the gas-liquid separation equipment enter the desorption tower for carbon dioxide desorption, resulting in a lean amine liquid and carbon dioxide gas. The lean amine liquid obtained from the desorption tower flows sequentially through the three-stage lean-rich amine liquid heat exchanger, the two-stage lean-rich amine liquid heat exchanger, and the first-stage lean-rich amine liquid heat exchanger, where it exchanges heat with the rich amine liquid. Wherein, the mass ratio of the rich amine liquid stream D to the mass of the rich amine liquid after the first heat exchange is (14-36):100, and the mass ratio of the rich amine liquid stream B to the mass of the rich amine liquid after the first heat exchange is (42-72):

100. Among them, the high-efficiency composite amine absorbent refers to the organic amine solution absorbent with an initial carbon dioxide desorption temperature of no more than 80°C.

13. The amine liquid recovery method according to claim 12, characterized in that, The initial desorption temperature of the carbon dioxide-rich amine solution in the high-efficiency composite amine absorbent is 60-80℃.

14. The amine liquid recovery method according to claim 13, characterized in that, The temperature of the rich amine solution after the first heat exchange is 55-65℃; the temperature of the rich amine solution after the second heat exchange is 75-85℃; and the temperature of the rich amine solution after heat exchange and desorption is 100℃ or higher. The mass ratio of the rich amine liquid stream A to the sum of the masses of the rich amine liquid stream A and the rich amine liquid stream B is (7-9):10; the mass ratio of the rich amine liquid stream C to the sum of the masses of the rich amine liquid stream C and the rich amine liquid stream D is (6-8):

10.

15. The amine recovery method according to claim 14, characterized in that, Part or all of the rich amine liquid stream B1 from the aforementioned rich amine liquid stream B enters a low-grade waste heat heating device, where it is heated using low-grade waste heat resources to obtain rich amine liquid stream E, which then enters the desorption tower for carbon dioxide desorption; wherein, the low-grade waste heat resources refer to waste heat resources with a temperature of 75-85℃; and / or Part or all of the rich amine liquid stream D1 from the aforementioned rich amine liquid stream D enters a medium-range waste heat heating device, where it is heated using medium-range waste heat resources to obtain rich amine liquid stream F, which then enters the desorption tower for carbon dioxide desorption; wherein, the medium-range waste heat resources refer to waste heat resources with a temperature of 85-95℃; and / or Part or all of the rich amine liquid stream D2 from the rich amine liquid stream D enters the desorption tower from the top of the desorption tower; and / or The liquid product obtained from the gas-liquid separation device enters a three-stage diversion device for diversion, resulting in a rich amine liquid stream G and a remaining rich amine liquid stream H excluding the rich amine liquid stream G. The rich amine liquid stream G enters a high-grade waste heat heating device, where it is heated using high-grade waste heat resources to obtain a rich amine liquid stream I, which then enters the desorption tower for carbon dioxide desorption. The high-grade waste heat resources refer to waste heat resources with a temperature of 105-115℃.

16. The amine liquid recovery method according to claim 15, characterized in that, The mass ratio of the rich amine liquid stream B1 to the sum of the masses of the rich amine liquid stream A and the rich amine liquid stream B is (1-3):10; and / or The rich amine liquid stream E enters the desorption tower from position A, where the temperature is 80-90°C; and / or The mass ratio of the rich amine liquid stream D1 to the sum of the masses of the rich amine liquid stream C and the rich amine liquid stream D is (1-2):10; and / or The rich amine liquid stream F enters the desorption tower from position B, where the temperature is 85-95°C; and / or The mass ratio of the rich amine liquid stream D2 to the sum of the masses of the rich amine liquid stream C and the rich amine liquid stream D is (1-2):10; and / or The mass ratio of the rich amine liquid stream G to the sum of the masses of the rich amine liquid stream G and the rich amine liquid stream H is (1-3):10; and / or The rich amine liquid stream I enters the desorption tower from position C, where the temperature is 100-110℃; and / or The amine-rich liquid stream H enters the desorption tower from position D, where the temperature is 100-110℃.

17. The amine liquid recovery method according to claim 14, characterized in that, The desorption tower has a bottom temperature of 100-115℃, a top temperature of 75-90℃, and a pressure of 0.04-0.15MPa; and / or The mass flow rate ratio of the rich amine liquid entering the first-stage lean-rich amine liquid heat exchanger to the lean amine liquid entering the third-stage lean-rich amine liquid heat exchanger is 1:0.9-0.97; and / or The temperature of the rich amine solution entering the primary lean-rich amine solution heat exchanger is 41-55℃; and / or The temperature of the lean amine liquid entering the three-stage lean-rich amine liquid heat exchanger is 100-115℃.

18. The amine liquid recovery method according to claim 12, characterized in that, The gaseous product obtained from the gas-liquid separation device enters the desorption tower for carbon dioxide desorption; wherein, the gaseous product obtained from the gas-liquid separation device enters the desorption tower from the condensation reflux module at the top of the desorption tower.

19. A carbon dioxide capture device, characterized in that, The carbon dioxide capture device is equipped with a carbon dioxide absorption tower and an amine liquid recovery system; the amine liquid recovery system is the amine liquid recovery system according to any one of claims 6-11; The rich amine liquid outlet of the carbon dioxide absorption tower is connected to the cold fluid flow channel inlet of the amine liquid recovery system; the hot fluid flow channel outlet of the primary lean-rich amine liquid heat exchanger of the amine liquid recovery system is connected to the organic amine absorbent inlet of the carbon dioxide absorption tower. The carbon dioxide absorption tower is also equipped with a flue gas inlet and a gas phase outlet.

20. A method for capturing carbon dioxide, characterized in that, The carbon dioxide capture method is performed using the carbon dioxide capture device of claim 19, and the carbon dioxide capture method includes: The high-efficiency composite amine absorbent and the flue gas to be treated enter the carbon dioxide absorption tower. In the carbon dioxide absorption tower, the high-efficiency composite amine absorbent captures the carbon dioxide in the flue gas to be treated, and a rich amine liquid is obtained. The amine-rich solution is recovered using the amine recovery method described in any one of claims 12-18 to obtain a lean amine solution; The lean amine liquid from the primary lean-rich amine liquid heat exchanger is cooled and then reintroduced into the carbon dioxide absorption tower as a high-efficiency composite amine absorbent to capture carbon dioxide in the flue gas to be treated.

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