Carbon capture and amine recovery system and method thereof

Abstract

The invention discloses a carbon capture and amine recovery system. The system comprises a rough washing tower, an absorption tower, a decarbonization tower and a deamination tower which are sequentially connected through a pipeline system, the rough washing tower is used for removing pollutants in the flue gas, including sulfur oxides, PM particles, hydrogen sulfide and the like; an amine solution spraying module is arranged at the upper part of the absorption tower, flue gas enters from a lower layer area of the absorption tower, and the amine solution spraying module sprays an amine solution to capture carbon dioxide in the flue gas so as to form a carbon capture solution and decarbonized flue gas; the decarburization tower is used for receiving the carbon capture solution and treating the carbon capture solution to obtain high-purity CO2 and a recovery solution; wherein the high-purity CO2 is discharged or retreated; the recovery solution flows back to an amine solution spraying module in the upper layer area of the absorption tower through a pipeline system to realize cyclic utilization; and the decarbonized flue gas is upwards conveyed to a deamination tower, and is discharged after deamination. Through one set of system, three-stage flue gas purification treatment of desulfurization, carbon capture and amine capture and recovery is realized, and the whole set of system is high in recovery efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of greenhouse gas emission reduction for ships, and in particular to a carbon capture and amine recovery system. Background Art

[0002] The International Maritime Organization has adopted a strategy for reducing greenhouse gas emissions from ships, proposing a vision of achieving zero greenhouse gas emissions in the international shipping industry by the middle of this century. Carbon capture through chemical amine absorption has become an effective measure.

[0003] In the existing chemical amine absorption method, amine vapor and its degradation products are usually captured by single-stage or double-stage washing, which leads to high amine concentration in the washing water, poor distribution of amine in the gas phase, and a large amount of amine is carried away and released into the atmosphere along with the exhaust gas flow and fine droplets. In addition, the existing design generally adopts an integrated absorption tower and water washing tower, which makes the entire tower too high, which is not conducive to installation and transportation. Summary of the invention

[0004] The present invention aims to overcome at least one defect of the above-mentioned prior art and provide a carbon capture and amine recovery system to achieve three-stage efficient flue gas purification treatment of desulfurization, carbon capture and amine capture and recovery in engine flue gas.

[0005] Specifically, the present invention provides a carbon capture and amine recovery system, comprising a rough scrubbing tower, an absorption tower, a decarbonization tower, and an amine removal tower which are sequentially connected through a pipeline system;

[0006] The rough scrubber is used to remove pollutants in the flue gas, including but not limited to sulfur oxides, PM particles, and hydrogen sulfide;

[0007] An amine solution spray module is provided at the upper part of the absorption tower. Flue gas enters from the lower area of ​​the absorption tower. The amine solution spray module sprays amine solution to capture carbon dioxide in the flue gas to form a carbon capture solution and decarbonized flue gas.

[0008] The decarbonization tower is used to receive the carbon capture solution and process it to obtain high-purity CO2 and a recovery solution; wherein the high-purity CO2 is discharged or reprocessed; the recovery solution flows back to the amine solution spray module at the top of the absorption tower through a pipeline system to achieve recycling;

[0009] The decarbonized flue gas is transmitted upward to the deamine tower and discharged after being deamined.

[0010] The carbon capture and amine recovery system of the present invention can achieve three-stage flue gas purification treatment of desulfurization, carbon capture and amine capture and recovery in engine flue gas. First, the flue gas generated in the engine will be treated by a rough scrubber to remove pollutants such as sulfur oxides, PM particles, hydrogen sulfide, etc. A cooling pipe is installed above the rough scrubber for spray cooling of the flue gas. A coarse filtration device is provided at the top of the rough scrubber for coarse filtration of the flue gas, and a wastewater collection pipeline is provided at the bottom of the rough scrubber. The top of the rough scrubber is connected to the middle and lower parts of the absorption tower; a booster fan is also provided between the pipelines of the two to increase the flow rate of the flue gas. A liquid level monitor, a temperature detector and a pH detector are installed in the absorption tower to detect the height of the liquid level, the temperature in the tower, and to infer the concentration of the amine solution based on the pH value for timely replenishment.

[0011] The deamine tower comprises a top area, an upper area and a lower area. Circulating water washing, cyclone demisting and reagent-added circulating water washing are used in the deamine tower to reduce amine emission and improve amine recovery efficiency, including the following steps:

[0012] S31: A circulating water washing module is provided in the lower area of ​​the deamine tower, and the circulating water washing module includes a water tank. The flue gas is washed with circulating water to recover the amine vapor therein. The circulating water absorbs the amine vapor and is collected in the water tank. After the treatment in this step, the amine content concentration in the flue gas is T1;

[0013] S32: A cyclone demister is provided at the top of the deamine tower to remove the residual ammonia vapor and aerosol in the flue gas for recycling. After this step, the amine content concentration in the flue gas is T2;

[0014] S33: a reagent cabinet is provided in the circulating water washing module, and reagents are added into the circulating water washing module to enhance the capture capability of amine substances during spraying, so as to further reduce the content of amine substances. After the treatment in this step, the concentration of amine content in the flue gas is T3;

[0015] An amine concentration tester is provided on the discharge pipe at the top of the deamine tower. After steps S31 and S32, when the amine concentration tester detects that T2 is higher than the set threshold value P1, the step S33 is started;

[0016] The following steps are also included:

[0017] S34: an acid washing circulation module is provided in the upper area of ​​the deamine tower, and an acid solution is sprayed cyclically for fine washing to further remove amine vapor and aerosol in the flue gas. After the treatment in this step, the amine content concentration in the flue gas is T4;

[0018] When the amine concentration tester detects that T3 is higher than the set threshold value P2, the pickling circulation module is turned on;

[0019] Where T4≤T3≤T2≤T1, where P2≤P1;

[0020] The bottom of the water tank is connected to the upper part of the absorption tower through a discharge pipe. The circulating water of the circulating water washing module becomes alkaline after absorbing amine, and the pH value increases. The pH value of the circulating water in the circulating water washing module is detected in the water tank. When it is higher than the set threshold value M1, the circulating water is discharged into the absorption tower through the discharge pipe at the bottom of the water tank or flows to the amine solution spray module in the upper area of ​​the absorption tower, so as to be recovered as amine solution for use in spraying and capturing carbon dioxide.

[0021] The bottom of the absorption tower is connected to the middle of the decarbonization tower through a pipeline system, which is used to transfer the carbon capture solution enriched with carbon dioxide to the decarbonization tower. The decarbonization tower is also equipped with detection instruments such as a liquid level monitor, a temperature detector, and a pH detector for real-time detection of relevant indicators in the tower. The carbon capture solution is separated into high-purity CO2 and a recovery solution in the decarbonization tower; the high-purity CO2 is transmitted upward for recovery or discharge; and the recovery solution flows back to the absorption tower through the bottom of the decarbonization tower through the pipeline system. The pipelines between the absorption tower and the decarbonization tower are equipped with pumps for liquid transmission.

[0022] On the other hand, the flue gas after decarbonization is further transmitted upward from the absorption tower to the deamine tower. After deamine in the deamine tower, the amine concentration is finally measured to meet the standard and can be discharged. The deamine tower is also equipped with a pH detector, a liquid level sensor, etc., for real-time detection of indicators in the tower. An amine concentration tester is also provided on the pipeline system connected to the top outlet of the deamine tower. After the flue gas is tested for qualified amine concentration, it is discharged to the discharge port through a one-way valve. The amine concentration tester measures the amine vapor concentration through a Fourier transform infrared spectrometer.

[0023] Furthermore, the present invention mainly realizes deamine by water washing. The carbon capture and amine recovery system described in the present invention also includes a circulating water washing module, which includes a water tank, a first spray assembly, a first pipeline, and a second pipeline; the water tank is installed below the deamine tower; the first spray assembly is arranged in the deamine tower; the bottom of the water tank is connected to the first spray assembly through a first pipeline; the top of the water tank is connected to the bottom of the deamine tower through a second pipeline; circulating water is pumped from the water tank to the first spray assembly for spraying, and the reflux water after spraying flows back to the top of the water tank through the pipeline system and flows into the water tank to realize water circulation, and the decarbonized flue gas moving upwards and transmitted upwards to the deamine tower is reversely operated to recover the amine vapor in the flue gas. Since the water in the water tank is lost during the circulation process, the present invention designs a water supply pipe above the water tank, and a liquid level sensor is provided in the water tank. When the liquid level is detected to be lower than the threshold, the water supply pipe can be opened for replenishment. The bottom of the water tank is connected to the upper part of the absorption tower through a pipeline system. The pH value of the circulating water is detected in the water tank. When it is higher than a set threshold, the circulating water is discharged into the absorption tower through the bottom discharge pipe or flows to the amine solution spray module in the upper area of ​​the absorption tower to be recovered as amine solution for use in spraying and capturing carbon dioxide. Typically, the washing water becomes alkaline after absorbing amine, and the pH value increases. Therefore, a pH threshold can be set to control the alkalinity of the washing water, and the discharge into the absorption tower is started when the threshold is triggered.

[0024] Furthermore, the carbon capture and amine recovery system of the present invention also includes a heat exchanger and a reagent cabinet; the heat exchanger is connected to the first pipeline; the reagent cabinet is connected to the second pipeline; the heat exchanger is used to cool the first pipeline to reduce steam generation; the reagent cabinet is used to capture amine impurities in the reflux water. The reagents in the reagent cabinet include substances that can react with amine compounds to enhance the effect of capturing amine impurities, such as amines, ammonia, aldehydes, and carbonic acid impurities, so that their content is further reduced; a control valve is provided below the reagent cabinet, which can remotely control the release of the reagent; the water cabinet is also provided with a pH detector, which reacts to whether the water in the water cabinet meets the requirements through the pH value; if the amine concentration is detected to be high through the pH value in the deammoniation tower, the valve of the reagent cabinet can be controlled to increase the dosage of the reagent and improve the removal efficiency of the amine compounds. Typical reagents include sodium hydroxide, potassium hydroxide, ion exchange resin, surfactant, acetone solvent, methanol solvent, etc. After the reagent is added and the circulating water is washed, the amine content in the flue gas can be reduced to 1ppm or less.

[0025] Furthermore, the carbon capture and amine recovery system described in the present invention also includes a circulating acid washing module; the circulating acid washing module includes a third pipeline, an acid cabinet, a fourth pipeline and a second spray assembly connected in sequence; the deamine tower includes a top area, an upper area and a lower area; the first spray assembly is installed in the lower area; the second spray assembly is installed in the upper area; one end of the third pipeline is connected to the lower part of the upper area, and the other end is connected to the upper part of the acid cabinet; one end of the fourth pipeline is connected to the lower part of the acid cabinet, and the other end is connected to the second spray assembly.

[0026] The deamination of the present invention adopts a two-stage washing mode. The flue gas after decarbonization enters the lower area of ​​the deamination tower, and is sprayed with circulating water to achieve a first-stage water washing. The flue gas after water washing continues to enter the upper interval upward, and is sprayed with circulating acid to achieve a second-stage washing, so that the amine vapor can be basically recovered; and the acid solution is sprayed for fine washing, which can further remove the amine vapor and aerosol in the flue gas. Further, the first pipeline is provided with a first pump, and the fourth pipeline is provided with a second pump.

[0027] Furthermore, a primary demister is provided on the top of the absorption tower; the primary demister is used to remove amine vapor and particulate matter; the primary demister is composed of multiple layers of honeycomb perforated plates stacked in an alternating manner, and when amine vapor passes through, it will condense into liquid, while also preventing larger particulate matter from passing through.

[0028] Furthermore, the cyclone demister includes a support, a baffle, a side wall, a recovery pipe and one or more cyclones; the cyclone is mounted on the central axis of the support; the side wall cover is arranged on the cyclone; a plurality of through holes are arranged on both sides of the side wall, and the two ends of the side wall are fixed to the inner wall of the support; the baffle is a conical mesh, the top is connected to the top inner wall of the support, and the side is connected to the side wall of the support; a collection tank is formed between the two sides of the side wall and the support, and the recovery pipe is connected to the collection tank. According to the smoke concentration, a single cyclone or multiple cyclones can be started by remote control.

[0029] Another inventive point of the present invention is that the secondary demisting method is adopted to achieve higher deamine efficiency and better effect. First, the present invention sets a primary demister at the top of the absorption tower to preliminarily remove most of the amine vapor and larger particles in the discharge. Further, the secondary demisting is achieved by the cyclone demister in the deamine tower. That is, the flue gas after the primary demisting flows from bottom to top through the cyclone demister, the cyclone performs rotational disturbance, the flue gas is accelerated in the cyclonic motion, and the carried micron-sized droplets first pass through the side wall horizontally. The side wall of the present invention has multiple through holes to facilitate the passage of droplets and flue gas, and the micron-sized droplets are then thrown vertically to the baffle, which is a conical mesh. After the small liquid condenses on the baffle to form larger droplets, it gravity settles into the collection tank at the edge of the deamine tower, and is recycled by installing a recovery pipe at the bottom of the collection tank. The clean flue gas after deamine is discharged upward through the mesh of the baffle; in the deamine tower, the amine emission is reduced by circulating water washing, cyclone demisting and circulating water washing with reagent addition to improve the amine recovery efficiency.

[0030] Furthermore, the decarbonization tower is also provided with an additive cabinet, which contains one or more of oxalic acid, citric acid, acetic acid, and ion exchange resin, and is used to increase the desorption rate of carbon dioxide. It also includes a CO2 processing module and an emission port. The CO2 processing module is connected to the top of the decarbonization tower through a pipeline system, and can collect high-purity CO2. The emission port is connected to the top of the deamine tower, and the emission port is connected to the CO2 processing module through a pipeline system. The captured CO2 can be collected and processed by the CO2 processing module, or discharged through the emission port. In addition, the flue gas with a standard amine concentration can be finally discharged through the emission port.

[0031] The present invention also provides a carbon capture and amine recovery method using the carbon capture and amine recovery system of the present invention, comprising the following steps:

[0032] S1: Flue gas rough treatment: Flue gas generated in the engine is treated by a rough scrubber to remove sulfur oxides, PM particles, and hydrogen sulfide pollutants;

[0033] S2: Carbon capture: The flue gas treated in step S1 enters the bottom of the absorption tower, and an amine solution is sprayed downward from the top of the absorption tower to capture carbon dioxide in the flue gas to form a carbon capture solution, which is further transported to the decarbonization tower to form a recovery solution and high-purity CO2; wherein the high-purity CO2 is transported to the CO2 processing module for recovery and storage, and the recovery solution returns to the top of the absorption tower for spraying to realize a spray cycle;

[0034] S3: Amine recovery: The flue gas treated in step S2 is discharged from the top of the absorption tower to achieve primary demisting, and then enters the deamine tower for circulating water washing, circulating acid washing and secondary demisting in the cyclone demister before being discharged.

[0035] Furthermore, in step S3,

[0036] The method of circulating water washing is: the water in the water tank is pumped into the first spray assembly to spray the lower area of ​​the deamine tower, and the reflux water flows back to the water tank through the pipeline system to achieve circulating water washing of the flue gas entering the deamine tower to reduce the concentration of amine substances in the flue gas.

[0037] The method of circulating acid washing is: the acid liquid in the acid cabinet is pumped into the second spray assembly to spray the upper area of ​​the deamine tower, and the reflux acid flows back to the acid cabinet through the pipeline system to realize circulating acid washing of the flue gas entering the deamine tower to reduce the concentration of amine substances in the flue gas; the acid cabinet may contain sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, citric acid, etc.

[0038] The secondary demisting method is as follows: the flue gas flows from bottom to top through the cyclone demister, wherein the cyclone performs rotational disturbance, the flue gas is accelerated in the cyclonic motion, and the carried micron-sized droplets first pass horizontally through the through holes on the side wall, and then are thrown vertically to the conical mesh baffle. The micron-sized droplets condense on the baffle to form larger droplets, and then settle by gravity into the collection tank, and are recovered and processed through the recovery pipe. After the deamine is removed, the clean flue gas passes through the mesh of the baffle and is discharged upward.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention separates the absorption tower and the deamine tower capable of water washing to facilitate transportation and flexible installation.

[0041] The present invention realizes three-stage flue gas purification treatment of desulfurization, carbon capture and amine capture recovery through a set of systems, so that the flue gas meets environmental protection standards. The whole system structure is reasonably designed and can achieve the lowest energy consumption and the highest recovery efficiency.

[0042] In the amine capturing stage, the present invention reduces the emission of amine in the chemical amine absorption method through a secondary washing method and a secondary demisting method, improves the recovery efficiency of amine, reduces environmental pollution and further reduces the content of amine.

[0043] At the same time, the secondary demisting in the present invention adopts a cyclone demisting method. Compared with the primary demisting, the cyclone demisting efficiency is higher, and the flue gas is rotated at high speed to form micron-sized droplets, which are then condensed through two turns to form larger droplets and then gravity-sedimented into the collection tank at the edge of the deamine tower, so the demisting effect is also good.

[0044] The present invention arranges pH value monitoring and amine concentration detection in the absorption tower, the decarbonization tower and the deamine tower, so as to realize real-time monitoring during the operation of the system.

[0045] The present invention also designs a CO2 processing module. The desorbed carbon dioxide enters the CO2 processing module through a carbon dioxide pipe, and can also be directly discharged through a connecting pipe. Different processing methods can be selected according to actual needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 Schematic diagram of the carbon capture and amine recovery system of the present invention.

[0047] Figure 2 It is a schematic structural diagram of the cyclone demister of the present invention. DETAILED DESCRIPTION

[0048] The drawings in the embodiments provide a more detailed description of the technical solutions in the embodiments of the present invention. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of the present invention, not all of them. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limitations on the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The embodiments of the present invention are described in detail below in conjunction with the drawings.

[0049] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0050] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present application, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0051] Example

[0052] like Figure 1As shown, a carbon capture and amine recovery system and method are used to treat the flue gas generated by the engine 100. It includes a rough scrubber 101, an absorption tower 102, a decarbonization tower 103, and a deamine tower 104, which are connected in sequence through a pipeline system; first, the flue gas generated in the engine will be treated by the rough scrubber 101 to remove pollutants such as sulfur oxides, PM particles, and hydrogen sulfide. A cooling pipe 10 is installed above the rough scrubber 101 for spray cooling of the flue gas. A rough filter device is provided at the top of the rough scrubber 101 for rough filtering of the flue gas, and a wastewater collection pipeline 20 is provided at the bottom of the rough scrubber 101. The top of the rough scrubber 101 is connected to the middle and lower parts of the absorption tower 102; a booster fan 105 is also provided between the pipelines of the two to increase the flow rate of the flue gas.

[0053] The absorption tower 102 is equipped with a liquid level monitor, a temperature detector and a pH detector to detect the liquid level, the temperature in the tower and to estimate the concentration of the amine solution according to the pH value so as to replenish it in time. A primary demister 211 is provided at the top of the absorption tower 102 to preliminarily remove most of the amine vapor and larger particles in the flue gas. The flue gas after decarbonization and primary demistering is discharged from the top of the absorption tower 102 to the amine removal tower 104.

[0054] The bottom of the absorption tower 102 is connected to the middle of the decarbonization tower 103 through a pipeline system, which is used to transmit the carbon capture solution enriched with carbon dioxide to the decarbonization tower 103. The decarbonization tower 103 is also equipped with detection instruments such as a liquid level monitor, a temperature detector, and a pH detector for real-time detection of relevant indicators in the tower. The upper part of the decarbonization tower 103 is connected to an additive cabinet 106, and the additive cabinet 106 contains oxalic acid, which is used to increase the desorption rate of carbon dioxide. In other embodiments of the present invention, the additive cabinet contains one or more mixtures of oxalic acid, citric acid, acetic acid, and ion exchange resin. The carbon capture solution is separated in the decarbonization tower 103 to form high-purity CO2 and a recovery solution; wherein the high-purity CO2 is transmitted upward to the CO2 processing module 400 to achieve recovery, and an amine concentration tester is also provided on the transmission pipeline system to monitor whether the gas at the discharge port meets the standard in real time. Or it is directly discharged to the discharge port 300 for discharge; and the recovery solution flows back to the absorption tower 102 through the bottom of the decarbonization tower 103 through the pipeline system. The pipelines between the absorption tower 102 and the decarbonization tower 103 are equipped with pumps for the transmission of liquid.

[0055] On the other hand, the flue gas after decarbonization and primary demisting is further transmitted upward from the absorption tower 102 to the deamine tower 104. After deamine in the deamine tower 104, the amine concentration is finally measured to meet the standard and can be discharged. The deamine tower 104 is also equipped with a pH detector, a liquid level sensor, etc., for real-time detection of indicators in the tower. An amine concentration tester 107 is also provided on the pipeline system connected to the top outlet of the deamine tower 104. After the flue gas is tested for qualified amine concentration, it is discharged to the discharge port 300 through the one-way valve. The amine concentration tester 107 measures the amine vapor concentration through a Fourier transform infrared spectrometer.

[0056] The specific deamine process includes a secondary washing process and a secondary demisting process. The deamine tower 104 includes a top area, an upper area and a lower area; the lower area is provided with a circulating water washing module, including a water tank 108, a first spray assembly 109, a first pipeline 30, a second pipeline 40, a heat exchanger 110 and a medicine cabinet 111; the water tank 108 is installed below the deamine tower 104; the first spray assembly 109 is arranged in the deamine tower 104; the bottom of the water tank 108 is connected to the first pipe The pipe 30 is connected to the first spray assembly 109; the top of the water tank 108 is connected to the bottom of the deamine tower 104 through the second pipe 40; the circulating water is pumped from the water tank 108 to the first spray assembly 109 for spraying, and the reflux water after spraying flows back to the top of the water tank 108 through the pipe system and flows into the water tank 108 to realize water circulation, and the circulating water sprays downward and the upward moving decarbonized flue gas transmitted to the deamine tower is reversed to recover the amine vapor in the flue gas. Since the water in the water tank 108 is lost during the circulation process, the present invention designs a water supply pipe 50 above the water tank 108, and the water tank 108 is provided with a liquid level sensor, etc. When the liquid level is detected to be lower than the threshold, the water supply pipe 50 can be opened for replenishment. The bottom of the water tank is connected to the upper part of the absorption tower through a discharge pipe. The pH value of the circulating water is detected in the water tank. When it is higher than the set threshold, the circulating water is discharged into the absorption tower or flows to the amine solution spray module in the upper area of ​​the absorption tower through the bottom discharge pipe to be recovered as amine solution for spraying and absorbing carbon dioxide. Typically, the washing water becomes alkaline after absorbing amine, and the pH value increases. Therefore, the pH threshold can be set to control the alkalinity of the washing water, and the water is discharged into the absorption tower when the threshold is triggered.

[0057] The heat exchanger 110 is connected to the first pipeline 30; the first pipeline 30 is provided with a first pump 112, and the medicine cabinet 111 is connected to the second pipeline 40; the heat exchanger 110 is used to cool the first pipeline 30 to reduce steam generation; the medicine cabinet 111 adds medicine to the circulating water washing module to enhance the capture ability of amine substances during spraying, such as amines, ammonia, aldehydes, and carbonic acid impurities, so as to further reduce their content. The upper area is provided with a circulating acid washing module; the circulating acid washing module includes a third pipeline 60, an acid cabinet 113, a fourth pipeline 70, and a second spray assembly 114 connected in sequence; the second spray assembly 114 is installed in the upper area; one end of the third pipeline 60 is connected to the lower part of the upper area, and the other end is connected to the upper part of the acid cabinet 113; one end of the fourth pipeline 70 is connected to the lower part of the acid cabinet 113, and the other end is connected to the second spray assembly 114. The fourth pipeline 70 is provided with a second pump 115. The acid cabinet may contain sulfuric acid, hydrochloric acid, phosphoric acid, acetic acid, citric acid, etc.

[0058] The flue gas after the primary defogger and the secondary washing is then passed through the cyclone defogger 200 to achieve the secondary defogger. The cyclone defogger 200 includes a baffle 201, a side wall 202, a recovery pipe 80, one or more cyclones 203, and a support 204; the cyclone 203 is installed on the central axis of the support 204; the side wall 202 is covered on the cyclone 203; a plurality of through holes are provided on both sides of the side wall 202, and the two ends of the side wall 202 are fixed to the inner wall of the support 204; the baffle 201 is a conical mesh with meshes for allowing the flue gas to pass through, the top is connected to the top inner wall of the support 204, and the side is connected to the side wall 202 of the support 204; a collection trough is formed between the two sides of the side wall 202 and the support 204, and the recovery pipe 80 is connected to the collection trough. That is, the flue gas after one demisting flows from bottom to top through the cyclone demisting device 200, and the cyclone 203 performs rotational disturbance, and the flue gas is accelerated in the cyclonic motion, and the carried micron-sized droplets first pass horizontally through the side wall 202. The side wall 202 of the present invention has a plurality of through holes to facilitate the passage of droplets and flue gas, and the micron-sized droplets are then thrown vertically to the baffle 201, and the baffle 201 is a conical mesh. Small liquids condense on the baffle 201 to form larger droplets, and then gravity settles into the collection tank at the edge of the deamine tower 104. The recovery pipe 80 is installed at the bottom of the collection tank for recovery treatment. After deamine, the clean flue gas passes upward through the amine concentration tester 107, and can be discharged from the discharge port 300 after the detection meets the standards. The emission port 300 is connected to the top of the deamine tower 104, and the emission port 300 is connected to the CO2 processing module 400 through a pipeline system. The captured CO2 can be collected and processed by the CO2 processing module 400, and can also be discharged through the emission port 300. In addition, the flue gas with a standard amine concentration can eventually be discharged through the emission port 300.

[0059] Therefore, amine emissions can be reduced and amine recovery efficiency can be improved by circulating water washing, cyclone demisting and circulating water washing with added reagents in the deamine tower. When the amine concentration tester detects a concentration higher than a set threshold, the acid washing circulation module is turned on to further reduce the amine concentration in the flue gas.

[0060] Typical reagents include sodium hydroxide, potassium hydroxide, ion exchange resin, surfactant, acetone solvent, methanol solvent, etc. The additive cabinet contains one or more of oxalic acid, citric acid, acetic acid, and ion exchange resin.

[0061] The above embodiments are only used to illustrate the technical solution of the present invention and are not intended to limit it. Although the present invention is described in detail with reference to the above preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention. Those skilled in the art may also make other changes within the spirit of the present invention and apply them to the design of the present invention, as long as they do not deviate from the technical effects of the present invention. These changes made according to the spirit of the present invention should be included in the scope of protection claimed by the present invention.

Claims

1. A carbon capture and amine recovery system, characterized in that: It includes a rough washing tower (101), an absorption tower (102), a decarbonization tower (103), and a deamine tower (104) which are sequentially connected through a pipeline system; The rough scrubber (101) is used to remove pollutants in the flue gas, including but not limited to sulfur oxides, PM particles, and hydrogen sulfide; an amine solution spray module is provided in the upper area of ​​the absorption tower (102); the flue gas enters from the lower area of ​​the absorption tower (102), and the amine solution spray module sprays amine solution to capture carbon dioxide in the flue gas to form a carbon capture solution; The decarbonization tower (103) is used to receive the carbon capture solution and process it to obtain high-purity CO2 and a recovery solution; wherein the high-purity CO2 is discharged or reprocessed; the recovery solution is refluxed to the amine solution spray module at the top of the absorption tower (102) through a pipeline system to achieve recycling; The decarbonized flue gas is transmitted upward to the deamination tower (104) and discharged after being deaminized.

2. The carbon capture and amine recovery system according to claim 1, characterized in that: The amine removal tower (104) comprises a top area, an upper area and a lower area. Circulating water washing, cyclone demisting and circulating water washing with a reagent are used in the amine removal tower to reduce amine emission and improve amine recovery efficiency. The steps include: S31: a circulating water washing module is arranged in the lower area of ​​the deamine tower, the circulating water washing module comprises a water tank (108), and the flue gas is washed with circulating water to recover the amine vapor therein, and the circulating water absorbs the amine vapor and is collected in the water tank (108). After the treatment in this step, the amine content concentration in the flue gas is T1; S32: a cyclone demister (200) is arranged at the top of the amine removal tower to remove residual ammonia vapor and aerosol in the flue gas for recovery treatment. After the treatment in this step, the amine content concentration in the flue gas is T2; S33: A reagent cabinet (111) is provided in the circulating water washing module, and reagents are added to the circulating water washing module to enhance the capture capability of amine substances during spraying, so as to further reduce the content of amine substances. After the treatment in this step, the concentration of amine content in the flue gas is T3.

3. The carbon capture and amine recovery system according to claim 2, characterized in that: An amine concentration tester (107) is provided on the discharge pipe at the top of the deamine tower (104). After steps S31 and S32, when the amine concentration tester (107) detects that T2 is higher than a set threshold value P1, step S33 is started; The following steps are also included: S34: an acid washing circulation module is provided in the upper area of ​​the deamine tower, and an acid solution is sprayed cyclically for fine washing to further remove amine vapor and aerosol in the flue gas. After the treatment in this step, the amine content concentration in the flue gas is T4; When the amine concentration tester (107) detects that T3 is higher than the set threshold value P2, the pickling circulation module is turned on; Among them, T4≤T3≤T2≤T1, and P2≤P1.

4. The carbon capture and amine recovery system according to claim 2, characterized in that: The bottom of the water tank (108) is connected to the upper part of the absorption tower (102) through a discharge pipe. The circulating water of the circulating water washing module becomes alkaline after absorbing amine, and the pH value increases. The pH value of the circulating water in the circulating water washing module is detected in the water tank. When it is higher than the set threshold value M1, the circulating water is discharged into the absorption tower through the discharge pipe at the bottom of the water tank or flows to the amine solution spray module in the upper area of ​​the absorption tower, so as to be recovered as amine solution for spraying and capturing carbon dioxide.

5. The carbon capture and amine recovery system according to claim 2, characterized in that: The circulating water washing module comprises a water tank (108), a first spray assembly (109), a first pipeline (30), and a second pipeline (40); the water tank (108) is installed below the deamine tower (104); the first spray assembly (109) is arranged in the deamine tower (104); The bottom of the water tank (108) is connected to the first spray assembly (109) via a first pipe (30); the top of the water tank (108) is connected to the bottom of the deamine tower (104) via a second pipe (40); Circulating water is pumped from the water tank (108) to the first spray assembly (109) for spraying. The reflux water after spraying flows back to the top of the water tank (108) through the pipe system and flows into the water tank (108), thereby realizing water circulation. The circulating water sprays downward and operates in the reverse direction with the upwardly moving decarbonized flue gas transmitted upward to the deamine tower to recover the amine vapor in the flue gas.

6. The carbon capture and amine recovery system according to claim 2, characterized in that: It also includes a heat exchanger (110); the heat exchanger (110) is connected to the first pipeline (30); the medicine cabinet (111) is connected to the second pipeline (40); The heat exchanger (110) is used to cool the first pipeline (30); the reagent cabinet (111) is used to add reagents into the circulating water washing module to enhance the capture capability of amine substances during spraying, including amine, ammonia, aldehyde, and carbonic acid impurities, so as to further reduce their content.

7. The carbon capture and amine recovery system according to claim 2, characterized in that: The circulating pickling module comprises a third pipeline (60), an acid tank (113), a fourth pipeline (70) and a second spray assembly (114) which are connected in sequence; The first spray assembly (109) is installed in the lower area of ​​the deamine tower (104); the second spray assembly (114) is installed in the upper area of ​​the deamine tower (104); One end of the third pipeline (60) is connected to the lower part of the upper area, and the other end is connected to the upper part of the acid cabinet (113); one end of the fourth pipeline (70) is connected to the lower part of the acid cabinet (113), and the other end is connected to the second spray assembly (114); the first pipeline (30) is provided with a first pump (112), and the fourth pipeline (70) is provided with a second pump (115).

8. The carbon capture and amine recovery system according to claim 1, characterized in that: A primary demister (211) is provided on the top of the absorption tower (102). The primary demister is composed of multiple layers of honeycomb perforated plates stacked in an alternating manner. When amine vapor passes through, it will condense into liquid and can also prevent larger particles from passing through.

9. The carbon capture and amine recovery system according to claim 2, characterized in that: The cyclone demister comprises a support (204), a baffle (201), a side wall (202), a recovery pipe (80), and one or more cyclones (203); the cyclone (203) is mounted on the central axis of the support (204); The side wall (202) is covered on the cyclone (203); a plurality of through holes are provided on both sides of the side wall (202); and both ends of the side wall (202) are fixed to the inner wall of the support (204); The baffle (201) is in a conical mesh shape, with the top connected to the top inner wall of the support (204), and the side connected to the side wall (202) of the support (204); A collecting trough is formed between the two sides of the side wall (202) and the support (204), and the recovery pipe (80) is connected to the collecting trough.

10. A carbon capture and amine recovery method, characterized in that: A carbon capture and amine recovery system comprising any one of claims 2 to 9; The working method of the circulating water washing module is as follows: water in the water tank (108) is pumped into the first spray assembly (109) through the first pump (112) to spray the lower area of ​​the deamine tower (104), and the reflux water flows back to the water tank (108) through the pipeline system to realize circulating water washing of the flue gas entering the deamine tower, so as to reduce the concentration of amine substances in the flue gas; The working method of the circulating acid washing module is as follows: the acid solution in the acid tank (113) is pumped into the second spray assembly (114) by a second pump (115) to spray the upper area of ​​the deamine tower (104); the reflux acid flows back to the acid tank (113) through the pipeline system, thereby realizing circulating acid washing of the flue gas entering the deamine tower, so as to reduce the concentration of amine substances in the flue gas; The working method of the cyclone demister is as follows: the flue gas flows through the cyclone demister from bottom to top, wherein the cyclone (203) performs a rotational disturbance, the flue gas is accelerated in the cyclonic motion, and the carried micron-sized droplets first pass horizontally through the through holes on the side wall (202), and then are thrown vertically to the conical mesh baffle (201), the micron-sized droplets condense on the baffle (201) to form larger droplets, and then settle by gravity into the collection tank, and are recovered and processed through the recovery pipe (80), and the clean flue gas after deamine is discharged upward through the mesh of the baffle (201).

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