Modular electrochemical carbon dioxide capture system enabling high purity hydrogen production

Abstract

The embodiment of the present disclosure provides a modular electrochemical carbon dioxide capture system capable of realizing high-purity hydrogen production, which comprises an absorption device, an electrolytic hydrogen production device, a first gas-liquid separation device and a second gas-liquid separation device, the absorption device contains a carbon dioxide absorption liquid, the electrolytic hydrogen production device comprises a plurality of electrolytic units, each electrolytic unit comprises an anode chamber, an intermediate chamber and a cathode chamber arranged in sequence, the absorption discharge port of the absorption device is communicated with each anode liquid inlet port, each anode liquid outlet port is communicated with the liquid inlet port of the first gas-liquid separation device, the liquid outlet port of the first gas-liquid separation device is communicated with each intermediate liquid inlet port, each intermediate liquid outlet port is communicated with the absorption liquid inlet port of the absorption device, each cathode liquid outlet port is communicated with the separation liquid inlet port of the second gas-liquid separation device, and the separation liquid outlet port of the second gas-liquid separation device is communicated with each cathode liquid inlet port. The system can improve the resource utilization rate and improve the safety of the system.

Description

TECHNICAL FIELD

[0001] Embodiments of the present disclosure belong to the technical field of gas purification and separation, and particularly relate to a modularized electrochemical carbon dioxide capture system capable of preparing high-purity hydrogen. BACKGROUND

[0002] CO2 capture, utilization and storage has become one of the hot topics of international society. In addition, there are a large number of CO2 capture or separation processes in the industrial fields of steelmaking, cement, chemical industry (such as synthetic ammonia, hydrogen production, natural gas purification) and the like.

[0003] In the related art, a thermal regeneration amine capture process is adopted, but the amine solvent regeneration of the thermal regeneration amine capture process needs to consume a large amount of heat energy, thereby causing the problems of high energy consumption of CO2 capture and low resource utilization rate. SUMMARY

[0004] Embodiments of the present disclosure aim to at least solve one of the technical problems existing in the prior art, and provide a modularized electrochemical carbon dioxide capture system capable of preparing high-purity hydrogen.

[0005] Embodiments of the present disclosure provide a modularized electrochemical carbon dioxide capture system capable of preparing high-purity hydrogen, which comprises:

[0006] An absorption device containing a carbon dioxide absorption liquid, the absorption device having an absorption gas inlet, an absorption gas outlet, an absorption liquid outlet and an absorption liquid inlet, the absorption gas inlet being used to introduce flue gas, and the absorption gas outlet being used to discharge flue gas from which carbon dioxide has been removed;

[0007] An electrolytic hydrogen production device, the electrolytic hydrogen production device comprising a plurality of electrolytic units, each electrolytic unit comprising an anode chamber, an intermediate chamber and a cathode chamber arranged in sequence, the anode chamber having an anode liquid inlet and an anode liquid outlet, the anode liquid inlet being in communication with the absorption liquid outlet, the intermediate chamber having an intermediate liquid inlet and an intermediate liquid outlet, the intermediate liquid outlet being in communication with the absorption liquid inlet, and the cathode chamber having a cathode liquid inlet and a cathode liquid outlet;

[0008] A first gas-liquid separation device, each anode liquid outlet being in communication with the first gas-liquid separation device, the first gas-liquid separation device being used to separate carbon dioxide, oxygen and anode separation solution from the anode gas-liquid mixture delivered by the anode liquid outlet, and the first gas-liquid separation device being in communication with each intermediate liquid inlet to provide the anode separation solution for the intermediate chamber;

[0009] A second gas-liquid separation device has a separation liquid inlet, a separation liquid outlet, and a separation gas outlet, the separation liquid inlet is communicated with the cathode liquid outlet, the separation liquid outlet is communicated with the cathode liquid inlet, and the separation gas outlet is used for discharging hydrogen, and the second gas-liquid separation device is used for separating hydrogen and the carbon dioxide absorption liquid from the cathode gas-liquid mixture delivered by the cathode liquid outlet.

[0010] In some embodiments of the present disclosure, the first gas-liquid separation device comprises:

[0011] A flash tank has a flash liquid inlet, a flash liquid outlet, a flash gas outlet, and a flash liquid return outlet, the flash liquid inlet is communicated with each of the anode liquid outlets, and the flash liquid outlet is communicated with the intermediate liquid inlet;

[0012] A condenser has a condensation gas inlet, a condensation liquid outlet, and a condensation gas outlet, the condensation gas inlet is communicated with the flash gas outlet, the condensation liquid outlet is communicated with the flash liquid return outlet, and the condensation gas outlet is used for discharging carbon dioxide and oxygen.

[0013] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system capable of preparing high-purity hydrogen further comprises:

[0014] A desulfurization device has a desulfurization gas inlet, a desulfurization gas outlet, a desulfurization liquid inlet, and a desulfurization liquid outlet, the desulfurization gas inlet is used for introducing flue gas, the desulfurization gas outlet is communicated with the absorption gas inlet, the desulfurization liquid inlet is used for introducing a desulfurization solution, and the desulfurization liquid outlet is used for discharging a sulfur-containing solution.

[0015] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system capable of preparing high-purity hydrogen further comprises:

[0016] A removal device has a removal gas inlet, a removal liquid inlet, and a removal liquid outlet, the removal gas inlet is communicated with the absorption gas outlet, the removal liquid inlet is used for introducing a removal solution, the removal liquid outlet is used for discharging an ammonia-containing solution, and the removal device is used for absorbing at least one of ammonia, an organic amine, and an amino acid salt.

[0017] In some embodiments of the present disclosure, the removal liquid outlet is communicated with the desulfurization liquid inlet.

[0018] In some embodiments of the present disclosure, the removal device further comprises a removal liquid return outlet, and the removal liquid return outlet is communicated with the desulfurization liquid outlet.

[0019] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system capable of preparing high-purity hydrogen further comprises:

[0020] a first heat exchange device having a first cold end and a first hot end, an inlet of the first cold end being in communication with the removal liquid outlet, an outlet of the first hot end being in communication with the desulfurization liquid inlet, an inlet of the first hot end being in communication with the desulfurization liquid outlet, and an outlet of the first hot end being in communication with the removal liquid inlet.

[0021] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system capable of high-purity hydrogen production further comprises:

[0022] a recovery device having a recovery liquid inlet, the recovery liquid inlet being in communication with the desulfurization liquid outlet.

[0023] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system capable of high-purity hydrogen production further comprises:

[0024] a second heat exchange device having a second cold end and a second hot end, an inlet of the second cold end being in communication with the absorption liquid outlet, an outlet of the second hot end being in communication with each of the anode liquid inlets, an inlet of the second hot end being in communication with each of the intermediate liquid outlets, and an outlet of the second cold end being in communication with the absorption liquid inlet.

[0025] In some embodiments of the present disclosure, the anode electrode in the anode chamber is an oxygen evolution electrode, and the oxygen evolution electrode is any one of a ruthenium oxide electrode, an iridium oxide electrode, a nickel-iron alloy electrode, and a nickel-iron oxide electrode.

[0026] the cathode electrode in the cathode chamber is a hydrogen evolution electrode, and the hydrogen evolution electrode is any one of a platinum-carbon electrode, a platinum-ruthenium-carbon electrode, a nickel-molybdenum alloy electrode, and a nickel-molybdenum oxide electrode.

[0027] The modular electrochemical carbon dioxide capture system capable of realizing high-purity hydrogen production of the present disclosure absorbs carbon dioxide in flue gas through a carbon dioxide absorption liquid of an absorption device, then resolves the carbon dioxide in the carbon dioxide absorption liquid through an electrolytic hydrogen production device, in the process of resolving the carbon dioxide, the electrolytic hydrogen production system can also realize electrolytic hydrogen production, finally, the gas-liquid mixture in the anode chamber and the gas-liquid mixture in the cathode chamber are separated through the first gas-liquid separation device and the second gas-liquid separation device respectively, realizing the recovery of carbon dioxide, hydrogen and oxygen, so as to realize the purpose of capturing carbon dioxide in flue gas, and in the process of resolving carbon dioxide, electrolytic hydrogen production is realized to improve the utilization rate of resources. In addition, the electrolytic hydrogen production device can also realize the regeneration of the carbon dioxide absorption liquid in the electrolysis process, so as to realize the circulation of the carbon dioxide absorption liquid, reduce the additional supplement of the carbon dioxide absorption liquid in the absorption device, and achieve the purpose of saving resources. In addition, the electrolytic hydrogen production device comprises a plurality of electrolytic units, the solution separated from the gas-liquid mixture in the anode chamber of each electrolytic unit is transported back to the intermediate chamber, the carbon dioxide is regenerated in the intermediate chamber, the oxygen in the gas-liquid mixture in the anode chamber is prevented from entering the cathode chamber, the reaction of oxygen and hydrogen in the cathode chamber is prevented, and the safety of the electrolytic hydrogen production device is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The structure schematic diagram of the modular electrochemical carbon dioxide capture system capable of realizing high-purity hydrogen production of the embodiments of the present disclosure.

[0029] In the drawings, various reference numbers represent the following:

[0030] 100, the modular electrochemical carbon dioxide capture system capable of realizing high-purity hydrogen production;

[0031] 10, the absorption device;

[0032] 20, the electrolytic hydrogen production device; 201, the anode chamber; 202, the cathode chamber; 203, the anion exchange film; 204, the intermediate chamber; 21, the anode electrode; 22, the cathode electrode;

[0033] 30, the first gas-liquid separation device; 31, the flash tank; 32, the condenser;

[0034] 40, the second gas-liquid separation device;

[0035] 50, the desulfurization device;

[0036] 60, the removal device;

[0037] 70, the first heat exchange device; 71, the first cold end; 72, the first hot end;

[0038] 80, the recovery device;

[0039] 90 second heat exchange device; 91 second cold end; 92 second hot end. DETAILED DESCRIPTION

[0040] Example embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings. While example embodiments of the present disclosure are shown in the drawings, it is understood that the present disclosure can be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the present disclosure to those skilled in the art.

[0041] It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has", "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order in which they are described, unless specifically identified as an order dependent step. It is also to be understood that additional or alternative steps can be employed.

[0042] Although the terms first, second, third, and the like can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first", "second", and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0043] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside," "outside," "inside," "outside," "below," "beneath," "above," and the like. Such spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is flipped, an element described as "below" or "below" another element or feature would then be oriented as "above" or "above" another element or feature. Thus, the example term "below" can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or in other orientations) and the spatially relative descriptors used herein are interpreted accordingly.

[0044] like Figure 1 As shown, the embodiment of the present disclosure provides a modular electrochemical carbon dioxide capture system 100 that can realize the production of high-purity hydrogen. The modular electrochemical carbon dioxide capture system 100 that can realize the production of high-purity hydrogen includes: an absorption device 10, an electrolytic hydrogen production device 20, a first gas-liquid separation device 30 and a second gas-liquid separation device 40. The absorption device 10 contains carbon dioxide absorption liquid. The absorption device 10 has an absorption air inlet, an absorption exhaust port, an absorption drain port and an absorption liquid inlet. The absorption air inlet is used to introduce flue gas, and the absorption exhaust port is used to discharge the flue gas decarbonated with carbon dioxide. The electrolytic hydrogen production device 20 includes a plurality of electrolysis units, each electrolysis unit includes an anode chamber, an intermediate chamber and a cathode chamber arranged in sequence. Each anode chamber 201 has an anode liquid inlet and an anode liquid drain port. Each anode liquid inlet is connected to the absorption liquid drain port, and each intermediate chamber is connected to the cathode chamber. 204 has an intermediate liquid inlet and an intermediate liquid discharge port, each cathode chamber 202 has a cathode liquid inlet and a cathode liquid outlet, each anode liquid discharge port is connected to the first gas-liquid separation device 30, the first gas-liquid separation device 30 is used to separate the anode gas-liquid mixture transported from the anode liquid discharge port into carbon dioxide, oxygen and anode separation solution, the first gas-liquid separation device 30 is connected to each intermediate liquid inlet to provide the anode separation solution to the intermediate chamber 204, each intermediate liquid discharge port is connected to the absorption liquid inlet, the second gas-liquid separation device 40 has a separation liquid inlet, a separation liquid discharge port and a separation exhaust port, the separation liquid inlet is connected to each cathode liquid discharge port, the separation liquid discharge port is connected to each cathode liquid inlet, the separation exhaust port is used to discharge hydrogen, and the second gas-liquid separation device 40 is used to separate the cathode gas-liquid mixture transported from the cathode liquid discharge port into hydrogen and carbon dioxide absorption liquid.

[0045] The modular electrochemical carbon dioxide capture system 100 of the present disclosure can realize high-purity hydrogen production. Flue gas enters the absorption device 10 through the absorption gas inlet of the absorption device 10. The absorption liquid inlet of the absorption device 10 introduces the carbon dioxide absorption liquid into the absorption device 10, which is in contact with the flue gas through spraying and reacts to absorb the carbon dioxide in the flue gas. After the carbon dioxide in the flue gas is absorbed, it is discharged from the absorption device 10 through the hand washing exhaust port. After the carbon dioxide absorption liquid absorbs the carbon dioxide in the flue gas, a carbon dioxide-rich solution is formed. The carbon dioxide-rich solution enters each anode chamber 201 through each anode liquid inlet. The carbon dioxide-rich solution serves as the electrolyte solution of the anode chamber 201. An electrolytic water reaction occurs in the anode chamber 201, and oxygen is generated. At the same time, the OH- concentration near the anode electrode 21 decreases, the acidity of the electrolyte solution increases, and the carbon dioxide is released from the solution. The anode liquid outlet delivers the gas-liquid mixture formed by the oxygen, carbon dioxide, and electrolyte solution to the first separation device. The first separation device separates the oxygen, carbon dioxide, and electrolyte solution in the gas-liquid mixture, and the electrolyte solution is delivered to each intermediate chamber 204 through the intermediate liquid inlet. An electrolytic water reaction occurs in the cathode chamber 202 and generates hydrogen gas, which is separated by the second separation device. The solution separated by the second separation device enters each cathode chamber 202 through each cathode liquid inlet. An electrolytic water reaction occurs in the cathode chamber 202, the OH- concentration near the cathode increases, and the cathode chamber 202 enters the intermediate chamber 204 through the anion exchange membrane 203 between the cathode chamber 202 and the intermediate chamber 204. The alkalinity of the solution in the intermediate chamber 204 is enhanced, the carbon dioxide absorption liquid is regenerated, and the regenerated carbon dioxide absorption liquid is delivered to the absorption device 10 through the absorption liquid inlet.

[0046] The modular electrochemical carbon dioxide capture system 100 of the present disclosure can realize high-purity hydrogen production. The carbon dioxide in the flue gas is absorbed by the carbon dioxide absorption liquid of the absorption device 10, and then the carbon dioxide in the carbon dioxide absorption liquid is resolved by the electrolytic hydrogen production device 20. In the process of resolving carbon dioxide, the electrolytic hydrogen production system can also realize electrolytic hydrogen production. Finally, the gas-liquid mixture in the anode chamber 201 and the gas-liquid mixture in the cathode chamber 202 are separated by the first gas-liquid separation device 30 and the second gas-liquid separation device 40, respectively, to realize the recovery of carbon dioxide, hydrogen and oxygen, thereby achieving the purpose of capturing carbon dioxide in the flue gas. At the same time, electrolytic hydrogen production is realized in the process of resolving carbon dioxide, so as to improve the utilization rate of resources. In addition, the electrolytic hydrogen production device 20 can also realize the regeneration of the carbon dioxide absorption liquid in the electrolysis process, so as to realize the circulation of the carbon dioxide absorption liquid, reduce the additional supplement of the carbon dioxide absorption liquid in the absorption device 10, and achieve the purpose of saving resources. In addition, the electrolytic hydrogen production device 20 comprises a plurality of electrolytic units, and the solution separated from the gas-liquid mixture in the anode chamber 201 of each electrolytic unit is transported back to the intermediate chamber 204 to regenerate carbon dioxide in the intermediate chamber 204, so as to avoid the oxygen in the gas-liquid mixture in the anode chamber 201 entering the cathode chamber 202, prevent the reaction between the oxygen and the hydrogen in the cathode chamber 202, and ensure the safety of the electrolytic hydrogen production device 10.

[0047] In some embodiments of the present disclosure, the anode electrode 21 in the anode chamber 201 is an oxygen evolution electrode, which includes but is not limited to any one of a ruthenium oxide electrode, an iridium oxide electrode, a nickel-iron alloy electrode, and a nickel-iron oxide electrode. Any one of the oxygen evolution electrode undergoes an electrolytic oxygen production process in the anode chamber 201 according to the formula: 4OH-4e-=O2↑+2H2O, and generates oxygen. The OH- in the anode chamber 201 decreases, the acidity of the electrolyte solution increases, and the carbon dioxide is resolved from the solution, thereby realizing the resolution of carbon dioxide. The cathode chamber 202 is isolated from the anode chamber 201 by the anion exchange membrane 203.

[0048] In some embodiments of the present disclosure, the cathode electrode 22 in the cathode chamber 202 is a hydrogen evolution electrode, which includes but is not limited to any one of a platinum-carbon electrode, a platinum-ruthenium-carbon electrode, a nickel-molybdenum alloy electrode, and a nickel-molybdenum oxide electrode. Any one of the hydrogen evolution electrode undergoes an electrolytic water reaction in the cathode chamber 202 according to the formula: 4H2O+4e-=2H2↑+4OH-, and generates hydrogen, and the OH- concentration near the cathode increases, the alkalinity of the solution in the cathode chamber 202 increases, and the carbon dioxide absorption liquid is regenerated.

[0049] Specifically, the absorption device 10 is an absorption tower, the absorption inlet is arranged at the bottom of the absorption tower, the absorption liquid inlet is arranged at the top or upper part of the absorption tower, the carbon dioxide absorption liquid is sprayed from the absorption liquid inlet at the top or upper part of the absorption tower to the bottom or lower part of the inside of the absorption tower, the flue gas enters the absorption tower from the absorption inlet at the bottom of the absorption tower and moves upwards in the absorption tower, the carbon dioxide absorption liquid sprayed downwards fully contacts the flue gas moving upwards, so that the carbon dioxide absorption liquid fully absorbs the carbon dioxide gas in the flue gas. The absorption liquid outlet is arranged at the bottom of the absorption tower, after the carbon dioxide absorption liquid absorbs the carbon dioxide, a carbon dioxide-rich solution is formed and is discharged from the absorption tower through the absorption liquid outlet arranged at the bottom of the absorption tower, and then is transported to each anode liquid inlet. The absorption gas outlet is arranged at the top of the absorption tower, after the flue gas fully reacts with the carbon dioxide absorption liquid, the flue gas from which the carbon dioxide is removed is discharged from the absorption tower through the absorption gas outlet arranged at the top of the absorption tower.

[0050] The anode liquid inlet of each anode chamber 201 is arranged at the bottom of the anode chamber 201, and the anode liquid outlet of each anode chamber 201 is arranged at the top of the anode chamber 201, so as to facilitate the discharge of the carbon dioxide, oxygen and liquid mixture. The cathode liquid inlet of each cathode chamber 202 is arranged at the bottom of the cathode chamber 202, and the cathode liquid outlet of each cathode chamber 202 is arranged at the top of the cathode chamber 202, so as to facilitate the discharge of the hydrogen gas and liquid mixture.

[0051] The second gas-liquid separation device 40 is a gas-liquid separator, the separation liquid inlet of the gas-liquid separator is arranged at the bottom of the gas-liquid separator, the separation liquid outlet is arranged at the middle or lower part of the gas-liquid separator, and the separation gas outlet is arranged at the top of the gas-liquid separator, so as to facilitate the discharge of the hydrogen gas.

[0052] In some embodiments of the present disclosure, the first gas-liquid separation device 30 comprises a flash tank 31 and a condenser 32, specifically, the flash tank 31 has a flash inlet, a flash outlet, a flash gas outlet and a flash return liquid outlet, the flash outlet is arranged at the bottom of the flash tank 31, the flash gas outlet is arranged at the top of the flash tank 31, and the condenser 32 has a condenser inlet, a condenser outlet and a condenser gas outlet, the condenser gas outlet is arranged at the top of the condenser tube, and the condenser outlet is arranged at the bottom of the condenser 32. The flash inlet is communicated with each anode outlet, the flash gas outlet is communicated with the condenser inlet, the condenser outlet is communicated with the return liquid outlet of the flash tank 31, the flash outlet is communicated with each intermediate inlet, and the condenser gas outlet is used to discharge carbon dioxide and oxygen. Specifically, the carbon dioxide, oxygen and solution mixture discharged from the anode outlet enters the flash tank 31 through the flash inlet, and is separated by flash in the flash tank 31 to obtain a flash separated liquid and a flash separated gas, the flash separated gas is discharged from the flash tank 31 through the flash gas outlet, enters the condenser inlet of the condenser 32, and is separated into a condenser separated gas and a condenser separated liquid after entering the condenser 32. The condenser separated gas is carbon dioxide and oxygen, the condenser separated gas is discharged from the condenser 32 through the condenser gas outlet, the condenser separated liquid is discharged from the condenser 32 through the condenser outlet, and then enters the flash tank 31 through the flash return liquid outlet. The condenser separated liquid and the flash separated liquid are discharged from the flash tank 31 through the flash outlet, and then enter the intermediate chamber 204 through the intermediate inlet.

[0053] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system 100 for high-purity hydrogen production further comprises a desulfurization device 50, the desulfurization device 50 has a desulfurization inlet, a desulfurization gas outlet, a desulfurization liquid inlet and a desulfurization liquid outlet, the desulfurization inlet is arranged at the bottom of the desulfurization device 50, the desulfurization gas outlet is arranged at the top of the desulfurization device 50, the desulfurization liquid inlet is arranged at the bottom of the desulfurization device 50, and the desulfurization liquid inlet is arranged at the top or upper part of the desulfurization device 50. The desulfurization inlet is used to introduce flue gas, the desulfurization gas outlet is communicated with the absorption inlet, the desulfurization liquid inlet is used to introduce desulfurization solution, and the desulfurization liquid outlet is used to discharge sulfur-containing solution.

[0054] Specifically, the flue gas enters the inside of the desulfurization device 50 from the desulfurization inlet, the desulfurization liquid inlet delivers the desulfurization solution to the inside of the desulfurization device 50, the desulfurization solution is sprayed into the desulfurization device 50 from the top or upper part of the desulfurization device 50, and fully reacts with the flue gas entering the desulfurization device 50 from the bottom to desulfurize the flue gas. The desulfurized flue gas is discharged from the desulfurization device 50 through the desulfurization gas outlet, and enters the absorption device 10 through the absorption inlet. The carbon dioxide in the desulfurized flue gas is absorbed by the absorption device 10.

[0055] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system 100 for high-purity hydrogen production further comprises a removal device 60 having a removal gas inlet, a removal liquid inlet and a removal liquid outlet. The removal gas inlet is arranged at the bottom of the desulfurization device 50, the desulfurization liquid inlet is arranged at the top or upper part of the desulfurization device 50, and the desulfurization liquid outlet is arranged at the bottom of the desulfurization device 50. The removal gas inlet is in communication with the absorption gas outlet, the removal liquid inlet is used to introduce the removal solution, the removal liquid outlet is used to discharge the removal solution which has absorbed ammonia, organic amine or amino acid salt, and the removal device is used to absorb at least one of ammonia, organic amine and amino acid salt.

[0056] Specifically, after the absorption device 10 absorbs the carbon dioxide in the flue gas, the absorption device 10 discharges the flue gas from which the carbon dioxide has been removed through the absorption gas outlet and transports the flue gas from which the carbon dioxide has been removed into the removal device 60 through the removal gas inlet. The removal solution enters the removal device 60 through the removal liquid inlet and is sprayed into the removal device 60 by spraying. The removal solution and the flue gas from which the carbon dioxide has been removed fully react to absorb ammonia in the flue gas, achieving the purpose of removal. The flue gas after removal is discharged from the removal device 60 through the removal gas outlet, and the removal solution which has absorbed ammonia is discharged from the removal device 60 through the removal liquid outlet.

[0057] In some embodiments of the present disclosure, the removal liquid outlet is in communication with the desulfurization liquid inlet. The removal solution which has absorbed ammonia is discharged from the removal device 60 through the removal liquid outlet and then enters the desulfurization liquid inlet of the desulfurization device 50. The removal solution which has absorbed ammonia can be used to desulfurize the flue gas, i.e., the removal solution which has absorbed ammonia is used as a desulfurization solution to desulfurize the flue gas, reducing the additional desulfurization solution added in the desulfurization device 50, achieving effective utilization and recycling of resources.

[0058] In some embodiments of the present disclosure, the removal device 60 further comprises a removal liquid return port, and the desulfurization liquid outlet is in communication with the removal liquid return port. When the desulfurization solution is in an unsaturated state after absorbing sulfur in the flue gas, the unsaturated desulfurization solution is transported by the desulfurization liquid outlet to the removal liquid inlet and enters the removal device 60. After the removal solution absorbs ammonia, the unsaturated desulfurization solution is transported together with the removal solution which has absorbed ammonia by the removal liquid outlet to the desulfurization liquid inlet, so that the unsaturated desulfurization solution absorbs sulfur in the flue gas.

[0059] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system 100 for high purity hydrogen production further comprises a first heat exchange device 70, which is arranged between the removal device 60 and the desulfurization device. The first heat exchange device 70 has a first cold end 71 and a first hot end 72. The inlet of the first cold end 71 is connected to the removal outlet, and the outlet of the first hot end 72 is connected to the desulfurization inlet. The removal solution absorbing ammonia enters the inlet of the first cold end 71 through the removal outlet and is discharged from the outlet of the first hot end 72 to the desulfurization inlet. The inlet of the first hot end 72 is connected to the desulfurization outlet, and the outlet of the first cold end 71 is connected to the removal return. The desulfurization solution absorbing sulfur enters the inlet of the first hot end 72 through the desulfurization outlet and is discharged from the outlet of the first cold end 71 to the removal return and enters the removal device 60. The desulfurization solution absorbing sulfur transfers heat to the removal solution absorbing ammonia through the first heat exchange device 70 to increase the temperature of the removal solution absorbing ammonia and reduce the temperature of the desulfurization solution absorbing sulfur.

[0060] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system 100 for high purity hydrogen production further comprises a recovery device 80, which has a recovery inlet connected to the desulfurization outlet of the desulfurization device 50. When the desulfurization solution in the desulfurization device 50 reaches saturation, the desulfurization solution in the desulfurization device 50 is transported to the recovery device 80 for treatment to obtain a sulfur dioxide product.

[0061] In some embodiments of the present disclosure, the modular electrochemical carbon dioxide capture system 100 for high purity hydrogen production further comprises a second heat exchange device 90, which is arranged between the absorption device 10 and the electrolytic hydrogen production device 20. The second heat exchange device 90 has a second cold end 91 and a second hot end 92. The inlet of the second cold end 91 is connected to the absorption outlet, and the outlet of the second hot end 92 is connected to each anode inlet. The inlet of the second hot end 92 is connected to each intermediate outlet, and the outlet of the second cold end 91 is connected to the absorption inlet.

[0062] Specifically, the carbon dioxide absorption solution enters the inlet of the second hot end 92 through each intermediate outlet and is discharged from the outlet of the second cold end 91 of the second heat exchange device 90 to the absorption inlet and enters the absorption device 10. The carbon dioxide-rich solution absorbing carbon dioxide enters the inlet of the second cold end 91 of the second heat exchange device 90 from the absorption outlet of the absorption device 10 and is discharged from the outlet of the second hot end 92 to each anode inlet. The carbon dioxide absorption solution and the carbon dioxide-rich solution exchange heat in the second heat exchange device 90.

[0063] It is understood that the above embodiments are only exemplary for illustrating the principles of the present disclosure, and the present disclosure is not limited thereto. Various modifications and improvements can be made by those of ordinary skill in the art without departing from the spirit and essence of the present disclosure, and these modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen, characterized in that: The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen includes: An absorption device containing a carbon dioxide absorption liquid, the absorption device having an absorption air inlet, an absorption exhaust port, an absorption liquid discharge port, and an absorption liquid inlet, the absorption air inlet being used to introduce flue gas, and the absorption exhaust port being used to discharge the flue gas decarbonated; An electrolytic hydrogen production device, comprising a plurality of electrolytic units, each electrolytic unit comprising an anode chamber, an intermediate chamber, and a cathode chamber arranged in sequence, the anode chamber having an anode liquid inlet and an anode liquid discharge port, the anode liquid inlet being connected to the absorption liquid discharge port, the intermediate chamber having an intermediate liquid inlet and an intermediate liquid discharge port, the intermediate liquid discharge port being connected to the absorption liquid inlet, and the cathode chamber having a cathode liquid inlet and a cathode liquid discharge port; a first gas-liquid separation device, each of the anode drain ports being in communication with the first gas-liquid separation device, the first gas-liquid separation device being configured to separate carbon dioxide, oxygen, and an anode separation solution from the anode gas-liquid mixture delivered from the anode drain port, the first gas-liquid separation device being in communication with each of the intermediate liquid inlets to provide the anode separation solution to the intermediate chamber; The second gas-liquid separation device has a separation liquid inlet, a separation liquid discharge port and a separation exhaust port. The separation liquid inlet is connected to the cathode liquid discharge port, the separation liquid discharge port is connected to the cathode liquid inlet, and the separation exhaust port is used to discharge hydrogen. The second gas-liquid separation device is used to separate hydrogen and the carbon dioxide absorption liquid from the cathode gas-liquid mixture transported by the cathode liquid discharge port.

2. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 1, characterized in that: The first gas-liquid separation device comprises: a flash tank, the flash tank comprising a flash liquid inlet, a flash liquid drain, a flash exhaust port, and a flash liquid return port, the flash liquid inlet being in communication with each of the anode liquid drain ports, and the flash liquid drain being in communication with the intermediate liquid inlet; The condenser has a condensation air inlet, a condensation liquid drain port and a condensation exhaust port. The condensation air inlet is connected to the flash exhaust port, the condensation liquid drain port is connected to the flash liquid return port, and the condensation exhaust port is used to discharge carbon dioxide and oxygen.

3. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 1, characterized in that: The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen also includes: A desulfurization device, the desulfurization device has a desulfurization air inlet, a desulfurization exhaust port, a desulfurization liquid inlet and a desulfurization liquid discharge port, the desulfurization air inlet is used to introduce flue gas, the desulfurization exhaust port is connected to the absorption air inlet, the desulfurization liquid inlet is used to introduce desulfurization solution, and the desulfurization liquid discharge port is used to discharge sulfur-containing solution.

4. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 3, characterized in that: The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen also includes: The removal device has a removal air inlet, a removal liquid inlet and a removal liquid discharge port, the removal air inlet is connected to the absorption exhaust port, the removal liquid inlet is used to introduce the removal solution, the removal liquid discharge port is used to discharge the ammonia-containing solution, and the removal device is used to absorb at least one of ammonia, organic amines, and amino acid salts.

5. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 4, characterized in that: The removal liquid outlet is communicated with the desulfurization liquid inlet.

6. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 5, characterized in that: The removal device further includes a removal liquid return port, which is communicated with the desulfurization liquid discharge port.

7. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 6, characterized in that: The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen also includes: The first heat exchange device has a first cold end and a first hot end, the inlet of the first cold end is connected to the removal drainage port, the outlet of the first hot end is connected to the desulfurization liquid inlet, the inlet of the first hot end is connected to the desulfurization drainage port, and the outlet of the first hot end is connected to the removal return liquid port.

8. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 4, characterized in that: The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen also includes: A recovery device is provided with a recovery liquid inlet, and the recovery liquid inlet is connected to the desulfurization liquid discharge port.

9. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 1, characterized in that: The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen also includes: A second heat exchange device, wherein the second heat exchange device has a second cold end and a second hot end, the inlet of the second cold end is connected to the absorption drain port, the outlet of the second hot end is connected to each of the anode liquid inlets, the inlet of the second hot end is connected to each of the intermediate drain ports, and the outlet of the second cold end is connected to the absorption liquid inlet.

10. The modular electrochemical carbon dioxide capture system capable of producing high-purity hydrogen according to claim 1, characterized in that: The anode electrode in the anode chamber is an oxygen evolution electrode, and the oxygen evolution electrode is any one of a ruthenium oxide electrode, an iridium oxide electrode, a nickel-iron alloy electrode, and a nickel-iron oxide electrode; The cathode electrode in the cathode chamber is a hydrogen evolution electrode, and the hydrogen evolution electrode is any one of a platinum-carbon electrode, a platinum-ruthenium-carbon electrode, a nickel-molybdenum alloy electrode, and a nickel-molybdenum oxide electrode.

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