Decarburization device and energy chemical engineering system

Abstract

The utility model provides a decarburization device and an energy chemical engineering system.The decarburization device is provided with a liquid storage device, and the liquid storage device is provided with a first liquid storage part used for storing lean amine liquid and a second liquid storage part used for storing rich amine liquid; the first liquid storage part and the second liquid storage part can provide or temporarily store certain lean amine liquid and rich amine liquid in the process of reducing or increasing the load of the decarburization device, so that certain buffer time is provided for adjustment of the desorption tower, and the problem that the adjustment rates of the desorption tower and the absorption tower are not matched is solved; the desorption tower can be slowly adjusted to the state matched with the load of the absorption tower, then the liquid level of the first liquid storage part and the liquid level of the second liquid storage part are kept in the stable state, the decarburization device can rapidly adapt to the working condition of load fluctuation through the adjusting mode, and the requirement for rapid fluctuation operation of the system is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy chemical industry, in particular to a decarbonization device and an energy chemical industry system. BACKGROUND

[0002] In the process of biomass gasification coupled with new energy green hydrogen to produce green methanol, a decarbonization device needs to be set to remove carbon dioxide in the synthesis gas so as to make the hydrogen-carbon ratio in the synthesis gas meet the requirements and improve the quality of the methanol product. At present, the decarbonization device often utilizes the chemical absorption characteristics of amine liquid (N-methyl diethanolamine solution) to remove carbon dioxide. Specifically, the decarbonization device includes an absorption tower and a desorption tower. In the absorption tower, lean amine liquid absorbs carbon dioxide to become rich amine liquid. The rich amine liquid enters the desorption tower, and in the desorption tower, carbon dioxide in the rich amine liquid is desorbed so that the rich amine liquid becomes lean amine liquid again. Then, the lean amine liquid returns to the absorption tower to absorb carbon dioxide again, and the process is repeated to purify the synthesis gas.

[0003] However, in actual application, due to the intermittency and instability of wind and light new energy, the wind and light green electricity is very uncontrollable, so that the amount of green hydrogen generated by the electrolytic cell is unstable. Therefore, the amount of decarbonization in the decarbonization device needs to fluctuate in real time to adapt to the amount of green hydrogen, so as to make the hydrogen-carbon ratio in the synthesis gas meet the requirements of methanol synthesis. However, due to the differences in structure, composition, reaction process and the like of the absorption tower and the desorption tower, the adjustment rates of the absorption tower and the desorption tower are not matched, which causes the current decarbonization device to be unable to meet the requirements of rapid fluctuation operation of the system. CONTENT OF THE UTILITY MODEL

[0004] Therefore, the present application provides a decarbonization device and an energy chemical industry system to at least solve the problem that the current decarbonization device cannot meet the requirements of rapid fluctuation operation of the system.

[0005] To achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0006] The present application provides a decarbonization device, which includes an absorption tower, a desorption tower and a liquid storage device. The lower part of the absorption tower is in communication with the upper part of the desorption tower, and the lower part of the desorption tower is in communication with the upper part of the absorption tower. The liquid storage device is arranged between the absorption tower and the desorption tower. The liquid storage device includes a first liquid storage part and a second liquid storage part. The first liquid storage part is in communication with the upper part of the absorption tower and the lower part of the desorption tower respectively, and the second liquid storage part is in communication with the lower part of the absorption tower and the upper part of the desorption tower respectively. The first liquid storage part is used to store lean amine liquid, and the second liquid storage part is used to store rich amine liquid.

[0007] Optionally, the first liquid storage part and the second liquid storage part are lean amine liquid storage tanks and rich amine liquid storage tanks which are independent of each other.

[0008] Optionally, the liquid storage device further comprises a third liquid storage part, which is in communication with the middle part of the absorption tower along the height direction and the middle part of the desorption tower along the height direction, respectively, and is used for storing semi-lean amine solution.

[0009] Optionally, the first liquid storage part, the second liquid storage part and the third liquid storage part are lean amine solution storage tank, rich amine solution storage tank and semi-lean amine solution storage tank, which are independent of each other.

[0010] Optionally, the liquid storage device comprises a liquid storage tank, and three independent cavities are arranged in the liquid storage tank, which correspond to the first liquid storage part, the second liquid storage part and the third liquid storage part.

[0011] Optionally, the inlet end and the outlet end of the first liquid storage part and the second liquid storage part are connected with control valves, respectively, and the control valves are used for controlling the liquid flow in and out of the corresponding first liquid storage part and second liquid storage part.

[0012] Optionally, the first liquid storage part and the second liquid storage part are respectively connected with liquid level detection meters, which are connected to the upper part and / or the lower part of the first liquid storage part and the second liquid storage part, respectively, and are used for detecting the liquid level of the first liquid storage part and the second liquid storage part.

[0013] Optionally, the decarburization device further comprises a control device; the control device is electrically connected with the control valves; the control device is used for controlling the control valve at the inlet end of the first liquid storage part to be opened and the control valve at the outlet end of the second liquid storage part to be opened when the load is reduced, and is used for controlling the control valve at the outlet end of the first liquid storage part to be opened and the control valve at the inlet end of the second liquid storage part to be opened when the load is increased; the control device is also electrically connected with the liquid level detection meters; and the control device is also used for controlling the opening size of each control valve according to the detection results of the liquid level detection meters.

[0014] The application also provides an energy chemical system, which comprises the decarburization device as described in any one of the preceding embodiments.

[0015] Optionally, the energy chemical system further comprises a heat exchanger, a condenser and a flash tank; the heat exchanger is connected between the absorption tower and the desorption tower, and is used for realizing heat exchange between the lean amine solution and the rich amine solution; the inlet end of the condenser is in communication with the heat exchanger, the outlet end of the condenser is in communication with the upper part of the absorption tower, and the condenser is used for reducing the temperature of the lean amine solution entering the absorption tower; the inlet end of the flash tank is in communication with the lower part of the absorption tower, the outlet end of the flash tank is in communication with the heat exchanger, and the flash tank is used for reducing the content of carbon dioxide in the rich amine solution.

[0016] Compared with the prior art, the decarburization device and the energy chemical system have the following advantages:

[0017] The decarburization device provided by the application is provided with a liquid storage device, the liquid storage device is provided with a first liquid storage part for storing lean amine liquid and a second liquid storage part for storing rich amine liquid, and the first liquid storage part and the second liquid storage part can provide or temporarily store a certain amount of lean amine liquid and rich amine liquid during the process of reducing the load or increasing the load of the decarburization device, thereby providing a certain buffer time for the adjustment of the stripping tower, improving the problem of the mismatching of the adjustment rates of the stripping tower and the absorption tower, and enabling the stripping tower to be slowly adjusted to a state matched with the load of the absorption tower, and then the liquid levels of the first liquid storage part and the second liquid storage part are kept in a stable state. The adjustment mode enables the decarburization device to quickly adapt to the working condition of load fluctuation and meet the requirement of rapid fluctuation operation of the system.

[0018] The energy chemical system provided by the application has the same or similar advantages as the foregoing decarburization device, and details are not repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0019] The accompanying drawings, which form a part of the present application, are used to provide further understanding of the present application, and serve as an explanation of the illustrative embodiments of the present application and their description, and do not constitute improper limitations to the present application. In the drawings:

[0020] Figure 1 is a schematic view of the decarburization device provided by the embodiment of the present application when the decarburization device is operated at a reduced load;

[0021] Figure 2 is a schematic view of the decarburization device provided by the embodiment of the present application when the decarburization device is operated at an increased load;

[0022] Figure 3 is a schematic view of the decarburization device provided by the embodiment of the present application when the decarburization device is operated at a reduced load;

[0023] Figure 4 is a schematic view of the decarburization device provided by the embodiment of the present application when the decarburization device is operated at an increased load.

[0024] BRIEF DESCRIPTION OF DRAWINGS

[0025] 1- absorption tower, 2- stripping tower, 3- liquid storage device, 31- first liquid storage part, 32- second liquid storage part, 33-

[0026] third liquid storage part, 4- control valve, 51- first heat exchanger, 52- second heat exchanger, 6- flash tank, 71- first condenser, 72- second condenser, 73- third condenser, 81- first amine liquid pump, 82- second amine liquid pump, 83- reflux pump. DETAILED DESCRIPTION

[0027] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are some of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of the present application.

[0028] The terms "first", "second", and the like in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a particular order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than that illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of a kind and do not limit the number of objects, for example, the first object can be one or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / " generally means that the front and rear associated objects are in an "or" relationship.

[0029] It should be understood that "some embodiments" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiments are included in at least one embodiment of the present application. Therefore, "in some embodiments" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner.

[0030] A decarburization device and an energy chemical system provided by the present application will be described in detail below by listing specific embodiments.

[0031] The decarburization device of the embodiments of the present application is suitable for a system for preparing methanol by using biomass gasification coupled with new energy green hydrogen. In the system for preparing methanol by using biomass, a fluidized bed gasification furnace or a fixed bed gasification furnace and the like are needed to generate crude synthesis gas by high-temperature gasification of biomass materials, and the crude synthesis gas is purified by a purification device to form synthesis gas for preparing methanol. The synthesis gas includes carbon monoxide (the proportion in the synthesis gas is about 20% to 40%), hydrogen (the proportion in the synthesis gas is about 20% to 40%), carbon dioxide (the proportion in the synthesis gas is about 15% to 45%), and inert components such as methane and nitrogen (the proportion in the synthesis gas is about 0 to 20%).

[0032] Since the hydrogen-carbon ratio of the synthesis gas is required to be between 2.05 and 2.15 for methanol synthesis, a decarburization device is needed to remove carbon dioxide in the process of preparing methanol, so as to reduce the concentration of carbon dioxide and make the hydrogen-carbon ratio of the synthesis gas entering the methanol synthesis device meet the requirements, so as to ensure the quality of the final methanol product.

[0033] Currently, decarbonization units in methanol production systems often utilize the chemical absorption properties of N-methyldiethanolamine solution (hereinafter referred to as "amine solution") to remove carbon dioxide. Traditional methanol production systems typically utilize biomass gasification to directly produce methanol. The composition and flow rate of syngas during biomass gasification are relatively stable, resulting in a stable amount of carbon dioxide removal and stable operation of the corresponding decarbonization unit. With the continuous maturation of new energy green electricity electrolysis hydrogen production technology, biomass-coupled green hydrogen methanol production systems have emerged. These systems can react carbon dioxide with green hydrogen, effectively reducing carbon dioxide emissions, thereby improving the utilization rate of green carbon, increasing production capacity, and also contributing to the local consumption of new energy green electricity.

[0034] However, in biomass-coupled green hydrogen methanol production systems, the intermittent and unstable nature of wind and solar power generation makes the amount of green hydrogen produced by the electrolyzer highly unpredictable, resulting in fluctuations. While some methods can mitigate this fluctuation by incorporating hydrogen storage facilities, these require very large facilities, significantly impacting system costs. Therefore, this application provides a decarbonization device capable of fluctuating operation, allowing the decarbonization rate to match the green hydrogen output, thereby controlling system costs and ensuring the system's methanol production efficiency.

[0035] Reference Figure 1 and Figure 2 As shown, the decarbonization device includes an absorption tower 1, a stripping tower 2, and a storage device 3. The lower part of the absorption tower 1 is connected to the upper part of the stripping tower 2, and the lower part of the stripping tower 2 is connected to the upper part of the absorption tower 1. The absorption tower 1 is used to absorb carbon dioxide into a rich amine solution, and the stripping tower 2 is used to strip the rich amine solution into a lean amine solution and carbon dioxide, and then return the lean amine solution to the absorption tower 1. The storage device 3 is located between the absorption tower 1 and the stripping tower 2. The storage device 3 includes a first storage section 31 and a second storage section 32. The first storage section 31 is connected to the upper part of the absorption tower 1 and the lower part of the stripping tower 2, respectively, and the second storage section 32 is connected to the lower part of the absorption tower 1 and the upper part of the stripping tower 2, respectively. The first storage section 31 is used to store the lean amine solution, and the second storage section 32 is used to store the rich amine solution.

[0036] Specifically, the lower part of absorption tower 1 is connected to the upper part of analytical tower 2, and the lower part of analytical tower 2 is connected to...

[0037] The upper part of the absorption tower 1 is connected in communication, and during the operation of the decarbonization device, the synthesis gas raw material generated by the biomass gasification enters the absorption tower 1 from the lower part of the absorption tower 1, and the synthesis gas raw material is in countercurrent contact with the lean amine liquid sprayed in the absorption tower 1. The main components of the lean amine liquid are amine liquid and water, which have strong absorption capacity for carbon dioxide, and can remove most of the carbon dioxide in the synthesis gas raw material. After the lean amine liquid absorbs the carbon dioxide, it becomes rich amine liquid, and the main components of the rich amine liquid are amine liquid, water and carbon dioxide, which have very weak absorption capacity for carbon dioxide. The rich amine liquid flows out from the lower part of the absorption tower 1 and is transported to the upper part of the stripping tower 2. The stripping tower 2 is usually in a low-pressure and high-temperature state, which can strip the carbon dioxide in the rich amine liquid, regenerate the rich amine liquid to become lean amine liquid again, and continue to be sent back to the upper part of the absorption tower 1 for recycling. The regenerated lean amine liquid is used, and the stripped carbon dioxide is discharged from the stripping tower 2. Thus, during the operation of the decarbonization device, the feed liquid of the absorption tower 1 comes from the discharge liquid of the stripping tower 2, and the discharge liquid of the absorption tower 1 is used as the feed liquid of the stripping tower 2. In actual application, the bottom part of the absorption tower 1 and the top part of the stripping tower 2 can be connected in communication, and the bottom part of the stripping tower 2 and the top part of the absorption tower 1 can be connected in communication. In this way, the reaction time of the lean amine liquid in the absorption tower 1 and the reaction time of the rich amine liquid in the stripping tower 2 can be increased. In addition, the bottom of the stripping tower 2 can be connected with a first amine liquid pump 81, which can pump the lean amine liquid stripped from the stripping tower 2 to the top of the absorption tower 1 to ensure smooth feeding of the absorption tower 1.

[0038] In addition, in some embodiments, a thermosyphon reboiler is arranged in the stripping tower 2, which works by natural circulation. The liquid at the bottom of the stripping tower 2 enters the thermosyphon reboiler and is partially vaporized by heating. The density of the vaporized material is smaller, and the density difference between the inlet and outlet materials causes the liquid at the bottom of the stripping tower 2 to be continuously siphoned into the thermosyphon reboiler. The vapor-liquid mixture after heating and vaporization returns to the tower automatically, forming a cycle.

[0039] The structure of the absorption tower 1 is relatively simple, and its control is relatively simple. When facing fluctuating conditions, the adjustment rate is fast and the response time is short. The structure of the stripping tower 2 is relatively complex, and its control is relatively complex. When facing fluctuating conditions, the adjustment rate is slow and the response time is long. Therefore, when facing fluctuating conditions, the adjustment rate of the absorption tower 1 is restricted by the stripping tower 2, and the adjustment rates of the two are not matched, which leads to the fact that the decarbonization device cannot meet the requirements of rapid fluctuation operation of the system.

[0040] The decarbonization device of the embodiment of the present application further comprises a liquid storage device 3 arranged between the absorption tower 1 and the stripping tower 2. The liquid storage device 3 comprises a first liquid storage part 31 and a second liquid storage part 32.

[0041] The first storage part 31 is connected with the upper part of the absorption tower 1 and the lower part of the desorption tower 2, and in actual application, the first storage part 31 can be connected with the top of the absorption tower 1 and the bottom of the desorption tower 2 respectively; the second storage part 32 is connected with the lower part of the absorption tower 1 and the upper part of the desorption tower 2 respectively, and in actual application, the second storage part 32 can be connected with the bottom of the absorption tower 1 and the top of the desorption tower 2 respectively. The first storage part 31 is used for storing lean amine liquid, and the second storage part 32 is used for storing rich amine liquid.

[0042] Figure 1 The schematic diagram of the decarbonization device in the embodiment of the present application is shown when the decarbonization device is running at a reduced load is shown, and the first storage part 31 is connected with the upper part of the absorption tower 1 and the lower part of the desorption tower 2, and in actual application, the first storage part 31 can be connected with the top of the absorption tower 1 and the bottom of the desorption tower 2 respectively; the second storage part 32 is connected with the lower part of the absorption tower 1 and the upper part of the desorption tower 2 respectively, and in actual application, the second storage part 32 can be connected with the bottom of the absorption tower 1 and the top of the desorption tower 2 respectively. The first storage part 31 is used for storing lean amine liquid, and the second storage part 32 is used for storing rich amine liquid. Figure 1 If the decarbonization device needs to run at a reduced load quickly, the lean amine liquid feed amount at the top of the absorption tower 1 needs to be reduced quickly, and the amount of carbon dioxide in the synthesis gas that can be absorbed by the lean amine liquid is reduced accordingly, thereby reducing the decarbonization load. The lean amine liquid feed of the absorption tower 1 comes from the bottom of the desorption tower 2, and in the desorption tower 2, the rich amine liquid containing carbon dioxide enters from the top of the desorption tower 2, and the carbon dioxide in the rich amine liquid is desorbed in the desorption tower 2 to flow to the top of the desorption tower 2 in a gaseous phase. The top of the desorption tower 2 is provided with a third condenser 73, and the third condenser 73 can cool and condense part of the gaseous phase into liquid. Part of the liquid is extracted as a product, and the other part returns to the desorption tower 2 through a reflux pipe and a reflux pump 83 to form reflux. In addition, because the lean amine liquid reacts with the synthesis gas raw material in the absorption tower 1 for a certain period of time, in the case of rapid reduction of the lean amine liquid feed amount at the top of the absorption tower 1, the rich amine liquid discharge amount at the bottom of the absorption tower 1 will be reduced with a short time lag, and then, in a short time, the rich amine liquid feed amount at the top of the desorption tower 2 will not change greatly, and under the influence of this factor and the reflux factor of the desorption tower 2, rapid reduction of the lean amine liquid discharge amount at the bottom of the desorption tower 2 will cause the liquid level at the bottom of the desorption tower 2 to rise quickly, causing the desorption tower 2 to overheat and the quality of the regenerated lean amine liquid to decrease, which will eventually affect the operation of the absorption tower 1.

[0043] The embodiment of the present application can send part of the lean amine liquid generated at the bottom of the desorption tower 2 to the first storage part 31 for temporary storage through the first storage part 31, so as to improve the situation that the liquid level at the bottom of the desorption tower 2 rises quickly, thereby avoiding the lean amine liquid discharge amount at the bottom of the desorption tower 2 from being greatly affected in the case of rapid reduction of the lean amine liquid feed amount at the top of the absorption tower 1, and helping to ensure the normal operation of the desorption tower 2. At the same time, the first storage part 31 will be at a low liquid level in the initial stage, which can allow the liquid level of the lean amine liquid in the first storage part 31 to rise slowly, and at the same time, more adjustment time can be given to the desorption tower 2 to slowly reduce the load of the desorption tower 2, so as to slowly reduce the lean amine liquid discharge amount, so that it eventually matches the feed amount of the absorption tower 1, and the liquid level of the first storage part 31 tends to be stable.

[0044] Meanwhile, due to the sudden decrease in the feed rate of lean amine solution at the top of absorber 1, as the reaction continues within absorber 1, the amount of rich amine solution flowing out from the bottom of absorber 1 will also decrease accordingly. This means that the feed rate of rich amine solution at the top of desorption tower 2 also needs to be reduced. As mentioned above, since the adjustment rate of desorption tower 2 is lower than that of absorber 1, if desorption tower 2 cannot be adjusted in time, it is easy to cause the gas-liquid phase balance within desorption tower 2 to be disrupted, leading to overheating of desorption tower 2, etc. In this embodiment, the second liquid storage section 32 stores rich amine solution, which can be supplied to the top of desorption tower 2. In this way, the feed rate of rich amine solution at the top of desorption tower 2 can be reduced slowly, thereby preventing a significant impact on the feed rate of rich amine solution at the top of desorption tower 2 when the output rate of rich amine solution at the bottom of absorber 1 is reduced.

[0045] Figure 2 A schematic diagram of the decarbonization device operating under increased load in an embodiment of this application is shown, with reference to... Figure 2 As shown, when the decarbonization unit needs to rapidly increase its load, the feed rate of lean amine solution at the top of absorber 1 needs to be increased quickly. Increasing the feed rate of lean amine solution increases the amount of carbon dioxide in the syngas that can be absorbed, thereby increasing the decarbonization load. However, the lean amine solution feed at the top of absorber 1 originates from the bottom of stripping tower 2. Therefore, increasing the feed rate of lean amine solution at the top of absorber 1 implies increasing the output rate of lean amine solution at the bottom of stripping tower 2. Understandably, if the feed rate of rich amine solution at the top of stripping tower 2 remains unchanged, rapidly increasing the output rate of lean amine solution at the bottom of stripping tower 2 will cause a rapid drop in the liquid level at the bottom of stripping tower 2, potentially leading to dry burning within stripping tower 2. Figure 2 In the illustrated embodiment, since the decarbonization unit previously operated at low load, the first storage section 31 stored lean amine solution. Therefore, when increasing the feed rate of lean amine solution at the top of the absorption tower 1, the lean amine solution stored in the first storage section 31 can be directly transported to the top of the absorption tower 1, thereby increasing the feed rate of lean amine solution at the top of the absorption tower 1 and increasing the load of the absorption tower 1. Thus, under the action of the first storage section 31, the output of lean amine solution at the bottom of the desorption tower 2 can be avoided from being significantly affected, which helps to ensure the normal operation of the desorption tower 2. At the same time, more adjustment time can be given to the desorption tower 2 to slowly increase the load and gradually increase the output of lean amine solution, so that it eventually matches the required feed rate of lean amine solution at the top of the absorption tower 1, while the liquid level in the first storage section 31 tends to stabilize.

[0046] Meanwhile, due to the sudden increase of the lean amine liquid feed at the top of the absorption tower 1, the amount of the rich amine liquid flowing out of the bottom of the absorption tower 1 also increases accordingly as the reaction in the absorption tower 1 continues, which means that the feed amount of the rich amine liquid at the top of the stripping tower 2 also needs to be increased. As described above, due to the lower adjustment rate of the stripping tower 2 than that of the absorption tower 1, if the stripping tower 2 cannot be adjusted in time, it is also easy to cause the damage of the gas-liquid phase balance in the stripping tower 2, causing the stripping tower to overheat and the like. However, in the embodiments of the present application, the second liquid storage part 32 can temporarily store the rich amine liquid from the bottom of the absorption tower 1 and supply it to the top of the stripping tower 2 when needed, without affecting the stable operation of the stripping tower 2. Then, by slowly increasing the feed amount of the rich amine liquid at the top of the stripping tower 2, the load of the stripping tower 2 can be slowly and smoothly increased to the load working condition matched with the absorption tower 1, so that the liquid level of the second liquid storage part 32 tends to be stable.

[0047] It should be noted that the adjustment rate of the decarbonization device as a whole is determined by the adjustment rate of the absorption tower 1, and when the adjustment rate of the stripping tower 2 cannot keep up with that of the absorption tower 1, the liquid storage device 3 provides a certain buffer time for the adjustment of the stripping tower 2, so that the stripping tower 2 can be slowly adjusted to finally reach the overall load of the system. At this time, the feed and discharge of the stripping tower 2 are matched with those of the absorption tower 1, and the first liquid storage part 31 and the second liquid storage part 32 of the liquid storage device 3 enter a new balanced state, and the liquid levels of the first liquid storage part 31 and the second liquid storage part 32 remain stable.

[0048] Therefore, the decarbonization device in the embodiments of the present application is provided with the liquid storage device 3 having the first liquid storage part 31 for storing the lean amine liquid and the second liquid storage part 32 for storing the rich amine liquid. The first liquid storage part 31 and the second liquid storage part 32 can provide or temporarily store a certain amount of lean amine liquid and rich amine liquid during the process of reducing or increasing the load of the decarbonization device, thereby providing a certain buffer time for the adjustment of the stripping tower 2, improving the problem of mismatching of the adjustment rates of the stripping tower 2 and the absorption tower 1, so that the stripping tower 2 can be slowly adjusted to a state matched with the load of the absorption tower 1, and then the liquid levels of the first liquid storage part 31 and the second liquid storage part 32 remain in a stable state. This adjustment mode enables the decarbonization device to quickly adapt to the working condition of load fluctuation and meet the requirement of rapid fluctuation operation of the system.

[0049] Alternatively, in some embodiments of the present application, the first liquid storage part 31 and the second liquid storage part 32 are two independent lean amine liquid storage tanks and rich amine liquid storage tanks. That is, the liquid storage device 3 in the embodiments includes two independent tank structures, which are more flexible to place each tank body. In actual application, the tank bodies can be placed flexibly according to the positions and site space of the absorption tower 1 and the stripping tower 2, thereby reducing the difficulty of building the decarbonization device.

[0050] Optionally, in some embodiments of the present application, the middle part of the stripping column 2 along its height direction is connected with the middle part of the absorption column 1 along its height direction, and the stripping column 2 is also used for stripping the rich amine solution into semi-lean amine solution and carbon dioxide, and sending the semi-lean amine solution back to the absorption column 1.

[0051] Specifically, the semi-lean amine solution is a state of amine solution between the lean amine solution and the rich amine solution, which has absorbed a certain amount of acid gas, but has not reached the acid gas load of the rich amine solution, and the main components of the semi-lean amine solution are still amine solution and water, so it still has a certain adsorption capacity for carbon dioxide, but the adsorption capacity is weaker than that of the lean amine solution. The different positions of the stripping column 2 along its height direction affect the residence time, stripping degree and temperature of the rich amine solution in the stripping column 2. In the middle part of the stripping column 2 along its height direction, the rich amine solution is stripped for a short time to generate semi-lean amine solution and carbon dioxide. In the bottom of the stripping column 2 along its height direction, that is, the bottom of the stripping column 2, the rich amine solution is stripped for a long time to generate lean amine solution and carbon dioxide. Therefore, in this embodiment, the middle part of the stripping column 2 along its height direction is connected with the middle part of the absorption column 1 along its height direction, so as to send the regenerated semi-lean amine solution back to the absorption column 1 for reaction, and the generated carbon dioxide is discharged out of the stripping column 2. In this way, the energy consumption of the decarbonization device can be further reduced, and the decarbonization efficiency can be improved. The middle part of the stripping column 2 is connected with a second amine solution pump 82, and the second amine solution pump 82 can pump the semi-lean amine solution stripped out of the stripping column 2 to the middle part of the absorption column 1.

[0052] Optionally, referring to Figure 3 and Figure 4 In some embodiments of the present application, the liquid storage device 3 further includes a third liquid storage part 33, which is connected with the middle part of the absorption column 1 along its height direction and the middle part of the stripping column 2 along its height direction respectively, and the third liquid storage part 33 is used for storing semi-lean amine solution.

[0053] Specifically, to adapt to the fluctuating operating conditions, the liquid storage device 3 of the present embodiment further includes a third liquid storage part 33, which is connected with the middle part of the absorption column 1 along its height direction and the middle part of the stripping column 2 along its height direction respectively, and the third liquid storage part 33 is used for storing semi-lean amine solution. The third liquid storage part 33 can improve the influence of the adjustment rate of the stripping column 2 on the adjustment rate of the absorption column 1, so that the system is not easily affected by the lower adjustment rate of the stripping column 2, thereby achieving a higher adjustment level.

[0054] Figure 3 Fig. 4 shows a schematic diagram of the decarbonization device of the present application when the load is reduced, and Fig. 5 shows a schematic diagram of the decarbonization device of the present application when the load is increased. Figure 3As shown, if the decarbonization device needs to quickly reduce the load operation, the semi-lean amine liquid feed quantity in the middle of the absorption tower 1 needs to be reduced, and the semi-lean amine liquid feed comes from the middle of the stripping tower 2. By arranging the third liquid storage part 33, more semi-lean amine liquid generated by the stripping tower 2 is sent to the third liquid storage part 33, thereby avoiding the semi-lean amine liquid discharge in the middle of the stripping tower 2 from being greatly affected, and helping to ensure the normal work of the stripping tower 2. At the same time, the third liquid storage part 33 will be at a lower liquid level at the initial stage, which can allow the liquid level of the semi-lean amine liquid to slowly rise. At the same time of slowly rising the liquid level, more adjustment time can be given to the stripping tower 2, so that the stripping tower 2 can slowly reduce the load to slowly reduce the semi-lean amine liquid discharge quantity, so as to finally match the feed quantity of the absorption tower 1, and at the same time make the liquid level of the third liquid storage part 33 tend to be stable.

[0055] At the same time, due to the reduction of the semi-lean amine liquid feed flow of the absorption tower 1, the flow of the rich amine liquid flowing out of the absorption tower 1 will also be reduced. At this time, by arranging the second liquid storage part 32, the second liquid storage part 32 stores the rich amine liquid, and the stored rich amine liquid can be supplied to the stripping tower 2, so as to slowly reduce the rich amine liquid feed quantity of the stripping tower 2, to avoid the rich amine liquid feed of the stripping tower 2 from being greatly affected by the absorption tower 1. Then, by slowly reducing the rich amine liquid feed quantity of the stripping tower 2, the load of the stripping tower 2 can be slowly and smoothly reduced to the load working condition matched with the absorption tower 1, so as to make the liquid level of the second liquid storage part 32 tend to be stable.

[0056] Figure 4 A schematic diagram of the decarbonization device in the embodiment of the present application when increasing the load operation is shown, referring to FIG. 3. Figure 4 As shown, when the decarbonization device needs to quickly increase the load operation, the semi-lean amine liquid feed quantity in the middle of the absorption tower 1 needs to be reduced, and the semi-lean amine liquid feed of the absorption tower 1 comes from the middle of the stripping tower 2. By arranging the third liquid storage part 33, the semi-lean amine liquid stored in the third liquid storage part 33 is transported to the absorption tower 1, so as to increase the semi-lean amine liquid feed quantity of the absorption tower 1, and also can avoid the semi-lean amine liquid discharge in the middle of the stripping tower 2 from being greatly affected, which helps to ensure the normal work of the stripping tower 2, and at the same time can give more adjustment time to the stripping tower, so that the stripping tower 2 slowly increases the load to slowly increase the semi-lean amine liquid discharge quantity, so as to finally match the feed quantity of the absorption tower 1, and at the same time make the liquid level of the third liquid storage part 33 tend to be stable.

[0057] Meanwhile, due to the sudden increase of the semi-lean amine liquid feed flow of the absorption tower 1, the flow of the rich amine liquid flowing out of the bottom of the absorption tower 1 is also increased accordingly, at this time, through the setting of the second liquid storage part 32, the second liquid storage part 32 can temporarily store the rich amine liquid from the bottom of the absorption tower 1, and will not affect the stable operation of the stripping tower 2. Then, by slowly increasing the rich amine liquid feed amount of the stripping tower 2, the load of the stripping tower 2 can be slowly and smoothly increased to the load working condition matched with the absorption tower 1, so that the liquid level of the second liquid storage part 32 tends to be stable.

[0058] Therefore, the decarbonization device in the embodiments of the present application can provide or temporarily store a certain amount of semi-lean amine liquid during the process of reducing or increasing the load of the decarbonization device by setting the liquid storage device 3, which further improves the influence of the adjustment rate of the stripping tower 2 on the adjustment rate of the absorption tower 1, improves the problem of mismatching between the adjustment rates of the stripping tower 2 and the absorption tower 1, and enables the decarbonization device to quickly adapt to the working condition of load fluctuation, thereby meeting the requirement of rapid fluctuation operation of the system.

[0059] Alternatively, in some embodiments of the present application, the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33 are lean amine liquid storage tanks, rich amine liquid storage tanks and semi-lean amine liquid storage tanks independent of each other. That is, the liquid storage device 3 in the present embodiment includes three tank body structures independent of each other, which is more convenient for flexible placement of each tank body. In actual application, each tank body can be placed flexibly according to the positions and site space of the absorption tower 1 and the stripping tower 2, thereby reducing the difficulty of building the decarbonization device.

[0060] Alternatively, in some embodiments of the present application, the liquid storage device 3 includes one liquid storage tank, and three independent cavities are arranged in the liquid storage tank, which correspond to form the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33. Specifically, two partitions are arranged in the interior of the liquid storage tank, which separate the liquid storage device 3 into three independent cavities, and correspond to form the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33. In this way, it is helpful to control the processing cost of the liquid storage device 3, and at the same time, the site space occupied by the liquid storage device 3 is reduced.

[0061] Alternatively, in some embodiments of the present application, the inlet end and the outlet end of the first liquid storage part 31 and the second liquid storage part 32 are respectively connected with a control valve 4, or in the case that the liquid storage device includes the third liquid storage part 33, the inlet end and the outlet end of the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33 are respectively connected with a control valve 4, and the control valve 4 is used to control the liquid in and out flow of the corresponding first liquid storage part 31, second liquid storage part 32 or third liquid storage part 33.

[0062] Specifically, the inlet end of the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33 refers to the end where the lean amine solution or the rich amine solution flows into the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33, and the outlet end of the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33 refers to the end where the lean amine solution or the rich amine solution flows out of the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33. The control valve 4 is used to adjust the flow rate, pressure and liquid level and other parameters of the fluid, so that in actual application, the liquid inflow and outflow of the first liquid storage part 31, the second liquid storage part 32 or the third liquid storage part 33 can be adjusted by the control valve 4, so that the adjustment rate of the absorption tower 1 and the stripping tower 2 can be matched faster, and the decarbonization device can adapt to the working condition of load fluctuation more quickly. In addition, the control valve 4 can be an automatic adjusting valve, which can automatically adjust the opening or closing of the valve according to the system operation condition, or a manual adjusting valve, which can be manually adjusted by a person. The specific type is not limited in this embodiment.

[0063] The system operation condition can automatically adjust the opening or closing of the valve, or a manual adjusting valve can be used to manually adjust the valve. The specific type is not limited in this embodiment.

[0064] Alternatively, in some embodiments of the present application, the first liquid storage part 31 and the second liquid storage part 32 are respectively connected with a liquid level detector, and the liquid level detector is connected to the upper part or the lower part of the first liquid storage part 31 and the second liquid storage part 32, respectively. Of course, in the case that the liquid storage device includes the third liquid storage part 33, the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33 are respectively connected with a liquid level detector. In the case that the liquid level detector is connected to the upper part, such as the top, of the first liquid storage part 31, the second liquid storage part 32 or the third liquid storage part 33, the liquid level detector can detect the highest height of the liquid surface in the first liquid storage part 31, the second liquid storage part 32 or the third liquid storage part 33. In the case that the liquid level detector is connected to the lower part, such as the bottom, of the first liquid storage part 31, the second liquid storage part 32 or the third liquid storage part 33, the liquid level detector can detect the lowest height of the liquid surface in the first liquid storage part 31, the second liquid storage part 32 or the third liquid storage part 33. The liquid level detector can issue an alarm when it detects that the liquid surface in the first liquid storage part 31, the second liquid storage part 32 or the third liquid storage part 33 is too high or too low, so as to prompt the personnel to pay attention and avoid that the too high or too low liquid surface of the first liquid storage part 31, the second liquid storage part 32 and the third liquid storage part 33 affects the adjustment process of the absorption tower 1 and the stripping tower 2.

[0065] Optionally, in some embodiments of this application, the decarbonization device further includes a control device electrically connected to the control valve 4. The control device is used to open the control valve 4 at the inlet of the first liquid storage section 31 during reduced load operation, allowing the first liquid storage section 31 to temporarily store the lean amine solution produced by the stripping tower 2, and simultaneously open the control valve 4 at the outlet of the second liquid storage section 32, allowing the second liquid storage section 32 to supply rich amine solution to the stripping tower 2. The control device is also used to open the control valve 4 at the outlet of the first liquid storage section 31 during increased load operation, allowing the first liquid storage section 31 to supply lean amine solution to the absorption tower 1, and simultaneously open the control valve 4 at the inlet of the second liquid storage section 32, allowing the second liquid storage section 32 to temporarily store the rich amine solution produced by the absorption tower 1.

[0066] Furthermore, when level gauges are connected to the first liquid storage section 31 and the second liquid storage section 32 respectively, the control device is also electrically connected to the level gauges. The control device can control the opening degree of each control valve 4 according to the detection results of the level gauges. For example, if the liquid level in the first liquid storage section 31 is detected to be too high, the control device can reduce the opening degree of the control valve 4 at the inlet end of the first liquid storage section 31 or increase the opening degree of the control valve 4 at the outlet end of the first liquid storage section 31, so as to reduce the liquid inflow into the first liquid storage section 31 and increase the liquid outflow, thereby gradually reducing the liquid level in the first liquid storage section 31.

[0067] To the normal range. The control principle of other liquid storage sections is similar, and will not be described in detail in this embodiment.

[0068] This application also provides an energy and chemical system, including a decarbonization device as described in any of the preceding claims. The energy and chemical system includes not only a methanol production system, but also a green SAF (Sustainable Aviation Fuel) system and a green natural gas system for new energy fluctuation application scenarios. The decarbonization device can quickly adapt to load fluctuation conditions, thereby helping to improve the efficiency of the system during rapid fluctuation operation.

[0069] Optionally, in some embodiments of this application, the energy and chemical system further includes a heat exchanger, a condenser, and a flash tank; the heat exchanger is connected between the absorption tower 1 and the stripping tower 2 to realize heat exchange between the lean amine solution and the rich amine solution; the inlet end of the condenser is connected to the heat exchanger, and the outlet end of the condenser is connected to the upper part of the absorption tower 1, and the condenser is used to reduce the temperature of the lean amine solution entering the absorption tower 1; the inlet end of the flash tank is connected to the lower part of the absorption tower 1, and the outlet end of the flash tank is connected to the heat exchanger, and the flash tank is used to reduce the carbon dioxide content in the rich amine solution.

[0070] Specifically, the absorption tower 1 has a requirement on the temperature of the lean amine liquid entering the tower, the lean amine liquid analyzed out of the analysis tower 2 has a higher temperature, and needs to be lowered through heat exchange to meet the temperature entering the absorption tower 1, so the system needs to be provided with a heat exchanger. The heat exchanger includes a first heat exchanger 51, which is arranged between the absorption tower 1 and the analysis tower 2. One inlet end of the first heat exchanger 51 is in communication with the bottom of the absorption tower 1, and the other inlet end is in communication with the bottom of the analysis tower 2. One outlet end of the first heat exchanger 51 is in communication with the top of the analysis tower 2, and the other outlet end is in communication with the top of the absorption tower 1. Thus, the first heat exchanger 51 has two streams of fluid, the lean amine liquid from the bottom of the analysis tower 2 and the rich amine liquid from the bottom of the absorption tower 1. The temperature of the rich amine liquid is lower than that of the lean amine liquid, so the rich amine liquid can lower the temperature of the lean amine liquid to a certain extent, so the first heat exchanger 51 can realize heat exchange between the lean amine liquid and the rich amine liquid.

[0071] In the case that the semi-lean amine liquid also flows through the decarbonization device, there is also a certain temperature difference between the temperature of the semi-lean amine liquid analyzed out of the analysis tower 2 and the temperature of the lean amine liquid, so the heat exchanger also includes a second heat exchanger 52, which is arranged between the absorption tower 1 and the analysis tower 2. One inlet end of the second heat exchanger 52 is in communication with the bottom of the analysis tower 2, and the other inlet end is in communication with the middle of the analysis tower 2 along the height direction. One outlet end of the second heat exchanger 52 is in communication with the top of the absorption tower 1, and the other outlet end is in communication with the middle of the absorption tower 1 along the height direction. Thus, the second heat exchanger 52 has two streams of fluid, the semi-lean amine liquid from the middle of the analysis tower 2 and the lean amine liquid from the bottom of the analysis tower 2, and can realize heat exchange between the lean amine liquid and the semi-lean amine liquid to further reduce the power consumption of the decarbonization device.

[0072]

[0073] The condenser includes a first condenser 71, which is located near the top of the absorption tower 1. The first condenser 71 can further lower the temperature of the lean amine liquid, so that the temperature of the lean amine liquid is lowered to meet the temperature entering the absorption tower 1. Similarly, in the case that the semi-lean amine liquid also flows through the decarbonization device, the condenser also includes a second condenser 72, which is located near the middle of the absorption tower 1. The second condenser 72 can further lower the temperature of the semi-lean amine liquid, so that the temperature of the semi-lean amine liquid is lowered to meet the temperature entering the absorption tower 1.

[0074] ​Optionally, since the rich amine solution in the stripping tower 2 is heated and regenerated, a large amount of mixed gas of water vapor, carbon dioxide and a small amount of amine solution vapor is generated, so in some embodiments of the application, the system further comprises a third condenser 73, which can cool the above-mentioned mixed gas, so that the condensable components such as water vapor and amine solution vapor change phase from gas to liquid, and the liquid material is then returned to the stripping tower 2 by a return pump 83 for re-analysis to improve the waste of materials.

[0075] The inlet end of the flash tank 6 is connected to the bottom of the absorption tower 1, and the outlet end of the flash tank 6 is connected to the heat exchanger. The flash tank 6 is used to reduce the content of carbon dioxide in the rich amine solution. The rich amine solution from the absorption tower 1 and other equipment is usually in a high pressure state and enters the flash tank 6. When the rich amine solution enters the flash tank 6, the pressure decreases rapidly. According to Henry's law, the solubility of a gas in a liquid is proportional to the partial pressure of the gas at a certain temperature. When the pressure decreases, the solubility of the carbon dioxide and other gases dissolved in the liquid decreases, and the carbon dioxide escapes from the liquid to form a gas phase, thereby reducing the content of carbon dioxide in the rich amine solution and facilitating the subsequent analysis of the stripping tower 2.

[0076] Finally, it should be noted that in this document, relational terms such as first and second and the like can only be used to distinguish one entity or action from another entity or action, without necessarily requiring or implying that these entities or actions are in any way mutually exclusive, or in any way arranged or ordered in succession or time. Moreover, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the listed element.

[0077] The same element outside.

[0078] The above description is only the preferred embodiment of the application and is not intended to limit the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A decarboxylation device, characterized by, The device comprises an absorption tower, a desorption tower and a liquid storage device. The lower part of the absorption tower is connected with the upper part of the desorption tower, and the lower part of the desorption tower is connected with the upper part of the absorption tower. The liquid storage device is arranged between the absorption tower and the desorption tower, and comprises a first liquid storage part and a second liquid storage part. The first liquid storage part is connected with the upper part of the absorption tower and the lower part of the desorption tower respectively, and the second liquid storage part is connected with the lower part of the absorption tower and the upper part of the desorption tower respectively. The first liquid storage part is used for storing lean amine liquid, and the second liquid storage part is used for storing rich amine liquid.

2. The decarboxylation device of claim 1, wherein, The first liquid storage part and the second liquid storage part are lean amine liquid storage tanks and rich amine liquid storage tanks which are independent of each other.

3. The decarboxylation device of claim 1, wherein, The liquid storage device further comprises a third liquid storage part which is connected with the middle part of the absorption tower along the height direction and the middle part of the desorption tower along the height direction respectively. The third liquid storage part is used for storing semi-lean amine liquid.

4. The decarboxylation device of claim 3, wherein, The first liquid storage part, the second liquid storage part and the third liquid storage part are lean amine liquid storage tank, rich amine liquid storage tank and semi-lean amine liquid storage tank which are independent of each other.

5. The decarboxylation device of claim 3, wherein, The liquid storage device comprises one liquid storage tank which is provided with three independent cavities corresponding to the first liquid storage part, the second liquid storage part and the third liquid storage part.

6. The decarboxylation device of claim 1, wherein, The inlet end and the outlet end of the first liquid storage part and the second liquid storage part are respectively connected with control valves which are used for controlling the liquid flow in and out of the corresponding first liquid storage part and second liquid storage part.

7. The decarboxylation device of claim 6, wherein, The first liquid storage part and the second liquid storage part are respectively connected with liquid level detection meters which are connected with the upper part and / or the lower part of the first liquid storage part and the second liquid storage part respectively. The liquid level detection meters are used for detecting the liquid level of the first liquid storage part and the second liquid storage part.

8. The decarboxylation device of claim 7, wherein, The device further comprises a control device. The control device is electrically connected with the control valves. The control device is used for controlling the control valve at the inlet end of the first liquid storage part to be opened and the control valve at the outlet end of the second liquid storage part to be opened when the load is reduced, and is used for controlling the control valve at the outlet end of the first liquid storage part to be opened and the control valve at the inlet end of the second liquid storage part to be opened when the load is increased. The control device is also electrically connected with the liquid level detection meters. The control device is also used for controlling the opening size of each control valve according to the detection result of the liquid level detection meters.

9. An energy-chemical system, characterized in that, The device further comprises a heat exchanger, a condenser and a flash tank.

10. The energy chemical system of claim 9, wherein, The heat exchanger is connected between the absorption tower and the desorption tower, and is used for realizing the heat exchange between the lean amine liquid and the rich amine liquid. The inlet end of the condenser is connected with the heat exchanger, and the outlet end of the condenser is connected with the upper part of the absorption tower. The condenser is used for reducing the temperature of the lean amine liquid entering the absorption tower. The inlet end of the flash tank is connected with the lower part of the absorption tower, and the outlet end of the flash tank is connected with the heat exchanger. The flash tank is used for reducing the content of carbon dioxide in the rich amine liquid. ​

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