Thermally insulated flash tank and carbon capture system

Abstract

A thermally insulated flash tank and a carbon capture system. The thermally insulated flash tank comprises a tank body (1), a heat storage tank (2) and heat exchange tubes (3), wherein at least part of the heat storage tank (2) is arranged around the peripheral side of the tank body (1); the heat storage tank (2) comprises a heat storage cavity (21), heat storage units (22) and a heat exchange medium being provided in the heat storage cavity (21), and the heat storage units (22) being arranged in the heat storage cavity (21) and being configured to exchange heat with the heat exchange medium so as to store or release heat; each heat exchange tube (3) is arranged in the tank body (1) and has two ends connected to the heat storage tank (2); the heat exchange medium is pumped into the heat exchange tubes (3), a liquid intake tube (4) and a liquid return tube (5); and the heat exchange medium is configured to exchange heat with a liquid or vapor in the tank body (1) so as to absorb or release heat.

Description

A heat-insulated flash evaporator and carbon capture system

[0001] Cross-references to related applications

[0002] This disclosure is based on and claims priority to Chinese Patent Application No. 202410998837.3, filed on July 24, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to the field of carbon dioxide capture technology, and more specifically, to an insulated flash tank and a carbon capture system. Background Technology

[0004] In carbon capture, utilization and storage technology, in order to solve the problem of high energy consumption of regeneration solution in desorption tower, a process is proposed to send the hot lean solution at the bottom outlet of the desorption tower into a low-pressure flash tank. The saturation temperature corresponding to the pressure of the flash tank is lower than the temperature of the lean solution. The lean solution boils and flashes to produce secondary steam in the flash tank. The secondary steam enters the desorption tower to release heat, thereby reducing the heat load of the reboiler and achieving the purpose of reducing desorption energy consumption.

[0005] However, in high-altitude and cold regions, the harsh environment and low temperatures mean that after the carbon capture system of a thermal power plant is shut down, the solution at the bottom of the flash tank will freeze at low temperatures, making it impossible to open and use the flash tank again, severely affecting the normal operation of the carbon capture system. If electric heating is used to directly heat the flash tank, a long waiting time is required, and electric heating will greatly increase the system's energy consumption, thereby increasing the system's operating costs. Summary of the Invention

[0006] This disclosure aims to at least partially address one of the technical problems in the related art.

[0007] Therefore, this disclosure proposes an insulated flash tank that can keep the liquid inside the flash tank warm, preventing the solution inside the flash tank from freezing when the carbon capture system is shut down, reducing the start-up waiting time of the flash tank, ensuring the normal operation of the flash tank and the carbon capture system, and reducing operating energy consumption.

[0008] This disclosure also proposes a carbon capture system.

[0009] The heat-insulating flash evaporator of this disclosure includes:

[0010] Tank body;

[0011] A heat storage box and heat exchange tubes are provided. At least part of the heat storage box is arranged around the periphery of the tank body. The heat storage box includes a heat storage cavity with an annular horizontal cross-section. The heat storage cavity contains a heat storage unit and a heat exchange medium. The heat storage unit is located in the heat storage cavity and is used to exchange heat with the heat exchange medium to store or release heat. The heat exchange tubes are located in the tank body and are connected to an inlet pipe and a return pipe at both ends, respectively. The inlet pipe and the return pipe are respectively connected to the heat storage box. The heat exchange medium is pumped into the heat exchange tubes, the inlet pipe, and the return pipe. The heat exchange medium is used to exchange heat with the liquid or gas in the tank body to absorb or release heat.

[0012] The insulated flash tank of this disclosure can keep the liquid in the flash tank warm, preventing the solution in the flash tank from freezing when the carbon capture system is shut down, reducing the start-up waiting time of the flash tank, ensuring the normal operation of the flash tank and the carbon capture system, and reducing operating energy consumption.

[0013] In some embodiments, the heat storage box has a cylindrical structure, the heat storage box is fitted around the tank body and is adapted to the size of the tank body, and the height of the heat storage box is not greater than half the height of the flash tank.

[0014] In this embodiment, the heat storage box is designed as a cylindrical structure to facilitate assembly with the tank body. The cylindrical structure can also provide thermal insulation protection around the tank body, reducing the rate of temperature drop in the insulated flash tank when it is shut down, thus ensuring the insulation effect on the tank body. Furthermore, the height of the heat storage box is set to be no more than half the height of the flash tank. This satisfies the coverage area requirements of the heat storage box on the tank body and the space requirements of the heat storage cavity while ensuring the arrangement of the pipelines connected to the tank body, thus guaranteeing the flow and heat exchange requirements of the heat exchange medium.

[0015] In some embodiments, the tank body includes a hemispherical lower end cover, the heat storage box includes a first box segment and a second box segment, the first box segment and the second box segment communicate with each other and jointly define the heat storage cavity, the first box segment is sleeved on the periphery of the tank body and adapted to the size of the tank body, and the second box segment is fitted to the lower end cover and adapted to the size of the lower end cover.

[0016] In this implementation, the heat storage tank is set up as a first section and a second section, which can protect the bottom and part of the periphery of the tank, enhance the heat insulation protection of the lower end cover of the tank, reduce the heat dissipation efficiency of the tank, and ensure the heat preservation effect of the tank and the liquid inside the tank.

[0017] In some embodiments, a plurality of heat exchange tubes are provided, and the plurality of heat exchange tubes are connected in parallel between the liquid inlet pipe and the liquid return pipe. The heat exchange tubes are provided with radially extending heat exchange fins, and the heat exchange fins are spaced apart along the extension direction of the heat exchange tubes.

[0018] In this implementation, by setting up multiple heat exchange tubes, the contact area between the heat exchange medium and the liquid or gas inside the tube can be increased to improve the heat exchange efficiency. Furthermore, by setting up heat exchange fins, the heat exchange contact area of ​​the heat exchange tube can be increased, further improving the heat exchange efficiency of the heat exchange medium inside the tank.

[0019] In some embodiments, the heat exchange tubes are in the form of a disc or annular structure, and a plurality of the heat exchange tubes are spaced apart in the vertical direction.

[0020] In this implementation, the length of the heat exchange tube inside the tank is increased to extend the flow path and flow time of the heat exchange medium inside the tank, thereby increasing the contact time between the heat exchange medium and the liquid or gas inside the tank and improving the heat exchange efficiency of the heat exchange medium inside the tank.

[0021] In some embodiments, a heat tracing assembly is included, comprising a heat tracing pipe, a heat tracing pump, and a heat tracing unit. The two ends of the heat tracing pipe are connected to the heat storage tank, and the heat exchange medium flows through the heat tracing pipe. The heat tracing pump and the heat tracing unit are disposed on the heat tracing pipe. The heat tracing pump is used to pump the heat exchange medium along the heat tracing pipe, and the heat tracing unit is used to exchange heat with the heat exchange medium in the heat tracing pipe to raise the temperature of the heat exchange medium.

[0022] In this implementation, a heat tracing component is installed, and the heat tracing unit is used as a second heat source to provide heat to the heat exchange medium. This avoids the heat in the heat storage box being depleted and unable to keep the liquid in the tank warm, increases the effective heat preservation time of the heat storage box, and facilitates the heat preservation of the tank and the liquid inside the tank.

[0023] In some embodiments, the heat tracing unit includes a heat collector and a heater arranged sequentially on a heat tracing pipe. The heat tracing assembly includes a temperature measuring instrument and a controller. The temperature measuring instrument is disposed in the tank. The temperature measuring instrument is electrically connected to the controller and is used to transmit the measured value. The controller is electrically connected to the heater to drive the heater to operate when the measured value is lower than a set value.

[0024] In this implementation, the temperature inside the tank is detected by a temperature measuring instrument. The heat collector and heater heat the heat exchange medium respectively. When the heat collector cannot meet the heating demand, that is, when the temperature inside the tank drops to the set temperature, the controller drives the heater to heat, realizing the continuous supply of the second heat source. This eliminates the limitation on the heat storage time of the tank due to the limited total heat storage in the heat storage box, and ensures the heat preservation effect on the tank and the liquid inside the tank.

[0025] In some embodiments, the heat storage unit includes a heat storage pipe and a heat storage medium disposed within the heat storage pipe. The heat storage pipe extends in a vertical direction, and multiple heat storage units are provided and spaced apart circumferentially within the heat storage cavity of the tank.

[0026] In this implementation, multiple heat exchange units are spaced apart in the heat storage chamber, and the heat storage medium is stored separately through heat exchange tubes. This increases the contact area between the heat exchange medium and the heat storage tubes, ensuring the efficiency of heat storage and heat release of the heat storage medium, so as to keep the tank and the liquid inside the tank warm.

[0027] In some embodiments, the heat storage tank is provided with a first hole for connecting to the return pipe and a second hole for connecting to the inlet pipe, the first hole being located above the second hole, and the first hole and the second hole having a set distance in the vertical direction;

[0028] Alternatively, the return pipe is connected to the top of the heat storage tank, and one end of the inlet pipe passes through the heat storage tank and is located at the bottom of the heat storage cavity.

[0029] In this embodiment, by increasing the distance between the location where the return pipe is connected to the tank and the location where the inlet pipe is connected to the tank, the flow path of the heat exchange medium in the heat storage box is increased to facilitate heat exchange of the heat exchange medium in the heat storage box, ensure the temperature of the heat storage medium at each location in the heat storage box is uniform, and thus facilitate the heat storage unit to store or release heat.

[0030] The carbon capture system of this disclosure includes a desorption tower and an insulated flash tank of any of the above embodiments. The desorption tower is provided with a drain pipe, and the insulated flash tank is located on the drain pipe. The insulated flash tank is provided with a steam pipe connected to the desorption tower.

[0031] The carbon capture system of this disclosure, by setting up an insulated flash tank, can prevent the solution in the flash tank from freezing when the carbon capture system is shut down, ensuring the normal operation of the flash tank and the carbon capture system, shortening the waiting time when the carbon capture system starts up, and reducing the operating energy consumption when the carbon capture system starts up. Attached Figure Description

[0032] Figure 1 is a schematic diagram of the structure of the heat-insulating flash evaporator according to an embodiment of the present disclosure.

[0033] Figure 2 is a schematic diagram of the structure of a heat-insulating flash evaporator according to another embodiment of the present disclosure.

[0034] Figure 3 is a schematic diagram of the heat exchange tube in the insulated flash tank according to an embodiment of the present disclosure.

[0035] Reference numerals: Tank 1; Heat storage box 2; Heat storage cavity 21; Heat storage unit 22; First box section 23; Second box section 24; Heat exchange tube 3; Liquid inlet pipe 4; Liquid return pipe 5. Detailed Implementation

[0036] Embodiments of this disclosure are described in detail below, with examples of these embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this disclosure, and should not be construed as limiting it.

[0037] As shown in Figures 1, 2, and 3, the heat-insulating flash tank of this embodiment includes a tank body 1, a heat storage box 2, and a heat exchange tube 3. At least a portion of the heat storage box 2 is arranged around the tank body 1. The heat storage box 2 includes a heat storage cavity 21, the horizontal cross-section of which is annular. The heat storage cavity 21 is provided with a heat storage unit 22 and a heat exchange medium. The heat storage unit 22 is located in the heat storage cavity 21 and is used to exchange heat with the heat exchange medium to store or release heat. The heat exchange tube 3 is located inside the tank body 1 and its two ends are respectively connected to an inlet pipe 4 and a return pipe 5. The inlet pipe 4 and the return pipe 5 are respectively connected to the heat storage box 2. The heat exchange tube 3, the inlet pipe 4, and the return pipe 5 are pumped with a heat exchange medium, which is used to exchange heat with the liquid or gas in the tank body 1 to absorb or release heat.

[0038] The insulated flash tank of this embodiment achieves partial thermal insulation protection of the tank 1 by placing the heat storage box 2 on the tank body 1. Simultaneously, heat conduction between the two is achieved during the insulation of the flash tank. The insulated flash tank has two states during use: a heat absorption and storage state and a heat release and insulation state. In the heat absorption and storage state, the flash tank and the carbon capture system are in operation. The heat exchange medium in the heat storage box 2 reaches the heat exchange tube 3 located in the tank body 1 through the inlet pipe 4. The heat exchange medium exchanges heat with the liquid or gas in the tank 1 through the heat exchange tube 3 to absorb heat. After absorbing heat, the heat exchange medium is discharged back through the return pipe 5 to the... The heat exchange medium in the heat storage tank 2 exchanges heat again with the heat storage unit 22 to store the heat in the heat storage unit 22. In the heat release and heat preservation state, the flash tank and carbon capture system are in the shutdown state. The heat exchange medium in the heat storage tank 2 reaches the heat exchange tube 3 located in the tank body 1 through the liquid inlet pipe 4. The heat exchange medium exchanges heat with the liquid in the tank body 1 through the heat exchange tube 3. The heat exchange medium releases heat to raise the temperature of the liquid in the tank body 1. After releasing heat, the heat exchange medium is discharged back to the heat storage tank 2 through the liquid return pipe 5 and exchanges heat again with the heat storage unit 22 to absorb the heat stored in the heat storage unit 22.

[0039] The insulated flash tank of this disclosure collects redundant heat during the operation of the flash tube. When the flash tank stops operating, the collected heat can be used to keep the liquid in the tank 1 warm, preventing the solution in the flash tank from freezing when the carbon capture system stops, reducing the start-up waiting time of the flash tank, ensuring the normal operation of the flash tank and the carbon capture system, and at the same time being energy-efficient and reducing the energy consumption of the flash tank when operating in low-temperature environments.

[0040] It should be noted that at least part of the heat storage box 2 is arranged around the tank body 1, which means that a part of the heat storage box 2 is arranged around the tank body 1, or the entire heat storage box 2 is arranged around the tank body 1.

[0041] Optionally, the inlet pipe 4 is equipped with a delivery pump, and the top of the heat storage tank 2 is equipped with a liquid replenishment hole and a vent hole.

[0042] Optionally, the heat exchange medium can be water or molten salt, wherein molten salt is a melt formed by melting salts, which is existing technology and its principle will not be described in detail here.

[0043] In some embodiments, as shown in FIG2, the heat storage box 2 is a cylindrical structure, the heat storage box 2 is fitted around the tank body 1 and is adapted to the size of the tank body 1, and the height of the heat storage box 2 is not greater than half the height of the flash tank.

[0044] Specifically, a support frame is fixedly installed around the tank body 1 near the bottom. The cylindrical heat storage box 2 is fitted onto the tank and supported on the support frame, which facilitates the installation of the heat storage box 2. The heat storage box 2 can provide heat insulation protection for the periphery of the tank body 1, reduce the heat loss rate of the insulated flash tank when it is stopped, increase the heat insulation effect of the tank body 1, and limit the height of the heat storage box 2. While meeting the connection requirements of the tank body 1, it ensures the heat insulation area of ​​the heat storage box 2 on the tank body 1 and the accommodating space of the heat storage cavity 21, and ensures the flow and heat exchange requirements of the heat exchange medium.

[0045] In some embodiments, as shown in FIG1, the tank body 1 includes a hemispherical lower end cover, and the heat storage box 2 includes a first box section 23 and a second box section 24. The first box section 23 and the second box section 24 communicate with each other and jointly limit the heat storage cavity 21. The first box section 23 is fitted around the tank body 1 and is adapted to the size of the tank body 1. The second box section 24 is fitted to the lower end cover and is adapted to the size of the lower end cover.

[0046] Specifically, the heat storage box 2 is divided into a first box section 23 and a second box section 24 in the vertical direction. The first box section 23 is a cylindrical structure with an opening at the bottom. The first box section 23 has a connecting rib extending radially along the first box section 23. The second box section 24 is composed of two hemispherical boxes with the same center. A supporting rib extending radially along the hemispherical boxes is provided between the two boxes. The ends of the two hemispherical boxes restrict a second opening. The second opening and the first opening are matched in size so that the first box section 23 and the second box section 24 are connected and together restrict the heat storage cavity 21.

[0047] The first section 23 and the second section 24 can provide heat insulation protection for the bottom and part of the periphery of the tank body 1, improve the heat preservation effect of the tank body 1, reduce the heat loss efficiency of the liquid in the small tank body 1 when the flash tank is stopped, and enhance the heat preservation effect of the tank body 1 and the liquid in the tank body 1.

[0048] Optionally, the second section 24 is provided with perforations in the vertical direction for the connecting pipes at the bottom of the tank 1 to pass through.

[0049] In some embodiments, as shown in Figures 1 and 2, a plurality of heat exchange tubes 3 are provided, and the plurality of heat exchange tubes 3 are connected in parallel between the liquid inlet pipe 4 and the liquid return pipe 5. The heat exchange tubes 3 are provided with heat exchange fins extending radially, and a plurality of heat exchange fins are provided at intervals along the extension direction of the heat exchange tubes 3.

[0050] Multiple heat exchange tubes 3 are installed to increase the contact area between the heat exchange medium and the liquid or gas inside the tube, thereby improving the heat exchange efficiency of the heat exchange medium in the tank 1. Heat exchange fins are installed to increase the heat exchange contact area between the heat exchange tubes 3 and the liquid or gas inside the tank 1, thereby further improving the heat exchange efficiency of the heat exchange medium in the tank 1.

[0051] In some embodiments, as shown in FIG3, the heat exchange tube 3 is in the form of a disc or annular structure, and multiple heat exchange tubes 3 are spaced apart in the vertical direction. Setting the heat exchange tube 3 in the form of a disc or annular structure can increase the flow path and flow time of the heat exchange medium in the tank 1, and increase the contact time between the heat exchange medium and the liquid or gas in the tank 1, so as to improve the heat exchange efficiency of the heat exchange medium in the tank 1.

[0052] In some embodiments, a heat tracing assembly is included, which includes a heat tracing pipe, a heat tracing pump, and a heat tracing unit. The two ends of the heat tracing pipe are connected to the heat storage tank 2 and a heat exchange medium flows through the heat tracing pipe. The heat tracing pump and the heat tracing unit are disposed on the heat tracing pipe. The heat tracing pump is used to pump the heat exchange medium along the heat tracing pipe, and the heat tracing unit is used to exchange heat with the heat exchange medium in the heat tracing pipe to raise the temperature of the heat exchange medium.

[0053] By setting up a heat tracing component, the heat exchange medium in the heat storage tank 2 is circulated and transported through a heat tracing pump and heat tracing pipes. The heat exchange medium flows through the heat tracing unit via the heat tracing pipes. At the location of the heat tracing unit, the heat exchange medium is heated by exchanging heat with the heat tracing unit, which ensures the heat source supply of the heat exchange medium and prevents the heat in the heat storage tank 2 from being exhausted and unable to keep the liquid in the tank 1 warm. This increases the effective heat preservation time of the heat storage tank 2 and facilitates the heat preservation of the tank 1 and the liquid in the tank 1.

[0054] In some embodiments, the heat tracing unit includes a flat-plate solar collector and an electric heater arranged sequentially on a heat tracing pipe. The flat-plate solar collector heats the heat exchange medium with solar energy, which is energy-saving, environmentally friendly, and can reduce energy consumption. When the flat-plate solar collector cannot meet the heating demand, the heat exchange medium can be heated by the electric heater.

[0055] The heat tracing assembly includes a temperature measuring instrument and a controller. The temperature measuring instrument is located inside the tank 1 and is electrically connected to the controller. The temperature measuring instrument detects the temperature inside the tank 1 and transmits the measured value to the controller. The controller is electrically connected to the electric heater. The electric heater, controller, and temperature measuring instrument are connected to the power grid. When the heat storage box 2 and the flat-plate solar collector cannot meet the heating demand of the heat exchange medium, the liquid temperature inside the tank 1 begins to drop. When the measured value received by the controller is lower than the set value, the controller drives the electric heater to operate to heat the heat exchange medium. This eliminates the limitation on the heat preservation time of the tank 1 due to the limited total heat storage in the heat storage box 2, and ensures the heat preservation effect of the tank 1 and the liquid inside the tank 1.

[0056] In some embodiments, as shown in Figures 1 and 2, the heat storage unit 22 includes a heat storage pipe and a heat storage medium disposed within the heat storage pipe. The heat storage medium is molten salt. The heat storage pipe extends in the vertical direction. Multiple heat storage units 22 are provided and are spaced apart along the circumference of the tank 1 within the heat storage cavity 21. This enables the separate storage of the heat storage medium, increases the contact area between the heat exchange medium and the heat storage pipe, and ensures the efficiency of heat storage and heat release of the heat storage medium, so as to keep the tank 1 and the liquid inside the tank 1 warm.

[0057] In some embodiments, the heat storage box 2 is provided with a first hole for connecting to the return pipe 5 and a second hole for connecting to the inlet pipe 4. The first hole is located above the second hole, and the first hole and the second hole are at a set distance in the vertical direction. The flow path of the heat exchange medium in the heat storage box 2 is adjusted by the connection position relationship between the inlet pipe 4 and the return pipe 5 and the heat storage box 2, thereby increasing the flow area of ​​the heat exchange medium in the heat storage box 2, improving the heat exchange efficiency of the heat exchange medium, ensuring the temperature of the heat storage medium in each area of ​​the heat storage box 2 is balanced, and thus facilitating the heat storage unit 22 to store or release heat.

[0058] In some embodiments, as shown in Figures 1 and 2, the return pipe 5 is connected to the top of the heat storage tank 2, and one end of the inlet pipe 4 passes through the heat storage tank 2 and is located at the bottom of the heat storage cavity 21. The inlet pipe 4 is extended into the heat storage tank 2 to adjust the flow path of the heat exchange medium, which is convenient for processing and is not limited by the connection position of the inlet pipe 4 and the heat storage tank 2. This improves the heat exchange efficiency of the heat exchange medium in the heat storage tank 2, ensures the temperature of the heat storage medium in each area of ​​the heat storage tank 2 is uniform, and facilitates the heat storage unit 22 to store or release heat.

[0059] The carbon capture system according to embodiments of this disclosure is described below.

[0060] The carbon capture system of this disclosure includes a desorption tower and an insulated flash tank of any of the above embodiments. The desorption tower is provided with a drain pipe, the insulated flash tank is located on the drain pipe, and the insulated flash tank is provided with a steam pipe connected to the desorption tower.

[0061] The carbon capture system of this disclosure, by setting up an insulated flash tank, can prevent the solution in the flash tank from freezing when the carbon capture system is shut down, ensuring the normal operation of the flash tank and the carbon capture system, shortening the waiting time when the carbon capture system starts up, and reducing the operating energy consumption when the carbon capture system starts up.

[0062] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined.

[0064] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0065] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0066] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0067] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A heat-insulated flash tank, comprising: a tank body; a heat storage box and a heat exchange pipe, at least part of the heat storage box being arranged around the tank body, the heat storage box comprising a heat storage cavity, a horizontal cross section of the heat storage cavity being annular, the heat storage cavity being provided with a heat storage unit and a heat exchange medium, the heat storage unit being arranged in the heat storage cavity and being used for heat exchange with the heat exchange medium to store or release heat, the heat exchange pipe being arranged in the tank body and having an inlet pipe and a return pipe connected at two ends thereof respectively, the inlet pipe and the return pipe being connected with the heat storage box respectively, the heat exchange pipe, the inlet pipe and the return pipe being pumped with the heat exchange medium, the heat exchange medium being used for heat exchange with liquid or gas in the tank body to absorb or release heat.

2. The heat-insulated flash tank according to claim 1, wherein the heat storage box is in a cylindrical structure, the heat storage box being sleeved around the tank body and being adapted in size to the tank body, a height dimension of the heat storage box being not greater than half of a height dimension of the flash tank.

3. The heat-insulated flash tank according to claim 1 or 2, wherein the tank body comprises a lower end cover in a semispherical shape, the heat storage box comprises a first box section and a second box section, the first box section being communicated with the second box section and jointly limiting the heat storage cavity, the first box section being sleeved around the tank body and being adapted in size to the tank body, the second box section being fitted to the lower end cover and being adapted in size to the lower end cover.

4. The heat-insulated flash tank according to any one of claims 1-3, wherein the heat exchange pipe is provided in plurality, the plurality of heat exchange pipes being arranged in parallel between the inlet pipe and the return pipe, and the heat exchange pipe is provided with heat exchange fins extending in a radial direction, the heat exchange fins being arranged in plurality at intervals along an extending direction of the heat exchange pipe.

5. The heat-insulated flash tank according to claim 4, wherein the heat exchange pipe is in a disc-shaped structure or an annular structure, and the plurality of heat exchange pipes are arranged at intervals in an up-down direction.

6. The heat-insulated flash tank according to any one of claims 1-5, comprising a heat tracing assembly, the heat tracing assembly comprising a heat tracing pipe, a heat tracing pump and a heat tracing unit, two ends of the heat tracing pipe being connected to the heat storage box and the heat tracing pipe being circulated with the heat exchange medium, the heat tracing pump and the heat tracing unit being arranged in the heat tracing pipe, the heat tracing pump being used for pumping the heat exchange medium along the heat tracing pipe, and the heat tracing unit being used for heat exchange with the heat exchange medium in the heat tracing pipe to warm up the heat exchange medium.

7. The heat-insulated flash tank according to claim 6, wherein the heat tracing unit comprises a heat collector and a heater arranged in sequence on the heat tracing pipe, the heat tracing assembly comprises a temperature measuring instrument and a controller, the temperature measuring instrument being arranged in the tank body, the temperature measuring instrument being electrically connected with the controller and being used for delivering a measured value, and the controller being electrically connected with the heater to drive the heater to operate when the measured value is lower than a set value. ​ ​ 8. The heat preservation flash tank according to any one of claims 1-7, wherein the heat storage unit comprises a heat storage pipe extending in the up-down direction and a heat storage medium arranged in the heat storage pipe, and a plurality of heat storage units are arranged in the heat storage cavity in the circumferential direction of the tank body.

9. The heat preservation flash tank according to any one of claims 1-8, wherein the heat storage tank is provided with a first hole for connecting with the liquid return pipe and a second hole for connecting with the liquid inlet pipe, the first hole is located above the second hole, and the first hole and the second hole have a set distance in the up-down direction. Or, the liquid return pipe is connected to the top of the heat storage tank, and one end of the liquid inlet pipe penetrates through the heat storage tank and is located at the bottom of the heat storage cavity.

10. A carbon capture system comprising a desorption tower and a heat preservation flash tank according to any one of claims 1-9, the desorption tower is provided with a liquid discharge pipeline, the heat preservation flash tank is arranged in the liquid discharge pipeline, and the heat preservation flash tank is provided with a steam pipeline connected with the desorption tower.

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