Method and system for recovering carbon dioxide from flue gas

Abstract

The application discloses a method and system for recovering carbon dioxide in flue gas, belonging to the field of recovering carbon dioxide in flue gas. After high-temperature flue gas is filtered, heat is released for the first time, and then after desulfurization and denitrification, heat is released for the second time. Finally, low-temperature flue gas is formed and is subjected to an adsorption reaction with solid amine particles. The solid amine particles, after absorbing carbon dioxide, are subjected to heat absorption and temperature rise for two times, and then are directly heated by high-temperature water vapor. After the solid amine particles, after carbon dioxide is separated, are cooled, the solid amine particles participate in the reaction again. The flue gas is subjected to heat exchange and temperature reduction for two times, so that the temperature of the flue gas is reduced, the flue gas is better adsorbed by the solid amine particles, and the heat released by the flue gas during temperature reduction is used for preheating the solid amine particles, which have adsorbed carbon dioxide, and gradually increasing the temperature of the solid amine particles, so that the use amount of steam is further reduced when the steam is used for heating.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of carbon dioxide recovery in flue gas, in particular to a carbon dioxide recovery method and system in flue gas. BACKGROUND

[0002] Carbon dioxide is an important industrial gas. In addition to nitrogen with the highest content, flue gas generated by combustion in industrial production also has a high concentration of carbon dioxide. Recycling carbon dioxide for reuse can further reduce carbon emissions and turn waste into treasure, which has very high economic value.

[0003] Among the existing carbon dioxide adsorption methods, the most mature and low-cost method is adsorption. The main principle of adsorption is to use a solid adsorbent to adsorb carbon dioxide in a mixed gas. This principle is based on the space structure and molecular polarity of carbon dioxide molecules. Select an adsorbent that has a stronger adsorption force on carbon dioxide components in a mixed gas than other components. Since the molecular attraction of each component in the mixed gas to the active sites on the surface of the adsorbent is different, when the mixed gas passes through the adsorbent loaded in the adsorption bed under a certain pressure, the adsorbent selectively absorbs carbon dioxide, thereby separating and recycling carbon dioxide gas.

[0004] At present, the most representative is solid amine adsorption of carbon dioxide. For example, Beijing Derun Chen Environmental Protection Technology Co., Ltd. has proposed an application number 2021106156225 invention patent, which discloses a carbon dioxide adsorbent and its preparation method and application. The adsorbent can adsorb carbon dioxide at low temperature and release the adsorbed carbon dioxide at high temperature.

[0005] In order to make the solid amine particles that have completed adsorption release carbon dioxide, the existing technology generally uses indirect heating or direct heating. Indirect heating refers to heating the solid amine particles to release carbon dioxide through heat exchange. Direct heating refers to using electric heating or steam heating to release carbon dioxide gas. The cost of using steam heating is lower.

[0006] The heat of high-temperature flue gas is generally used through waste heat recovery. The existing technology does not use the waste heat of flue gas to release carbon dioxide from solid amine particles. SUMMARY

[0007] The purpose of the present application is to provide a carbon dioxide recovery method and system in flue gas. Before the flue gas is adsorbed by solid amine particles to adsorb carbon dioxide, the flue gas is cooled twice through heat exchange to reduce its temperature for better adsorption by solid amine particles. The heat released by the cooling of the flue gas is used to preheat the solid amine particles that have adsorbed carbon dioxide, gradually increasing its temperature, thereby further reducing the amount of steam used when using steam heating.

[0008] The technical scheme adopted by the present application to achieve the above technical purpose is as follows: a method for recovering carbon dioxide from flue gas, comprising the following steps:

[0009] 1) high-temperature flue gas is filtered to remove impurities and remove internal dust impurities, becomes flue gas after impurities removal, and performs first heat exchange with solid amine particles for absorbing carbon dioxide, part of the solid amine particles are analyzed to release carbon dioxide, the cooled flue gas is subjected to desulfurization and denitrification treatment to form clean flue gas;

[0010] 2) the clean flue gas performs second heat exchange with the solid amine particles for absorbing carbon dioxide, low-temperature flue gas is formed to perform adsorption reaction with the solid amine particles, and the flue gas after adsorption is discharged;

[0011] 3) the solid amine particles for absorbing carbon dioxide after reaction first perform heat exchange with the clean flue gas in step 2) to increase the temperature, and then perform heat exchange with the flue gas after impurities removal in step 1) to continue increasing the temperature;

[0012] 4) the solid amine particles after temperature rising in step 3) are introduced into high-temperature water vapor to make the solid amine particles analyze the absorbed carbon dioxide, the analyzed carbon dioxide is subjected to dehumidification and then compressed and stored, and the solid amine particles are cooled and then returned to step 2) to perform adsorption reaction with the low-temperature flue gas.

[0013] As an optimization scheme of the method for recovering carbon dioxide from flue gas, the temperature of the flue gas after impurities removal is not more than 350℃, and the temperature of the low-temperature flue gas is not more than 60℃.

[0014] As another optimization scheme of the method for recovering carbon dioxide from flue gas, the temperature of the high-temperature water vapor is 110-140℃.

[0015] A system for recovering carbon dioxide from flue gas, comprising a filtering and impurity removing device, a waste heat analyzing device, a desulfurization and denitrification device, a preheating device, a carbon dioxide adsorption device and a carbon dioxide analyzing device, wherein high-temperature flue gas first passes through the filtering and impurity removing device to remove the internal solid particle impurities, the formed flue gas after impurities removal releases heat in the waste heat analyzing device, and then passes through the desulfurization and denitrification device to remove sulfur oxides and nitrogen oxides, the formed clean flue gas releases heat again in the preheating device, the finally formed low-temperature flue gas enters the carbon dioxide adsorption device to perform adsorption reaction with the solid amine particles, the solid amine particles after adsorbing carbon dioxide first absorb heat in the preheating device, then are sent into the waste heat analyzing device to absorb heat again, and finally are directly heated by high-temperature water vapor in the carbon dioxide analyzing device, the solid amine particles after analyzing carbon dioxide are cooled by a particle cooling device and then are sent into the carbon dioxide adsorption device again.

[0016] As an optimization scheme of the above-mentioned carbon dioxide recovery system in flue gas, the waste heat resolving device and the preheating device have the same structure, including a shell with a carbon dioxide discharge pipe and a first solid amine particle outlet at the top and bottom respectively, and a solid amine particle inlet pipe arranged at one side of the carbon dioxide discharge pipe; the inside of the shell is provided with a plurality of partition pipe layers, which divide the shell into a plurality of heat exchange chambers from top to bottom; each of the partition pipe layers is formed by bending a flue gas pipe and has a layered structure with gaps, and the adjacent two heat exchange chambers are communicated through the gaps; after the solid amine particles enter the shell from the solid amine particle inlet pipe, they are heated by heat exchange with the flue gas flowing in the partition pipe layers in the process of passing through the heat exchange chambers in turn, and finally discharged from the first solid amine particle outlet; the carbon dioxide gas resolved by the heating of the solid amine particles is discharged from the carbon dioxide discharge pipe and collected; an air inlet distribution pipe with an air inlet pipe interface and an air outlet gathering pipe with an air outlet pipe interface are symmetrically arranged outside the shell; one end of all the flue gas pipes forming the partition pipe layers is communicated with the air inlet distribution pipe, and the other end is communicated with the air outlet gathering pipe.

[0017] As another optimization scheme of the above-mentioned carbon dioxide recovery system in flue gas, the carbon dioxide resolving device includes a cylinder, a gas outlet and a solid amine particle inlet are arranged at the top of the cylinder, a second solid amine particle outlet and a high-temperature vapor inlet pipe are arranged at the bottom of the cylinder, and a plurality of partition cylinders with open ends and concentric with the cylinder are arranged in the inside of the cylinder, which divide the cylinder into a plurality of annular channels; the solid amine particles discharged from the solid amine particle inlet flow along the annular channels from top to bottom, in the process, the high-temperature vapor inlet pipe arranged at one end of the cylinder is provided with a semicircular diverging head, which uniformly sprays high-temperature vapor to the bottom of all annular channels and heats the solid amine particles in the process of rising along the annular channels; the resolved carbon dioxide and water vapor are discharged from the gas outlet, and the solid amine particles are discharged from the second solid amine particle outlet.

[0018] As another optimization scheme of the above-mentioned carbon dioxide recovery system from flue gas, the carbon dioxide adsorption device comprises at least one set of solid amine adsorption carbon dioxide unit, each set of solid amine adsorption carbon dioxide unit comprises a closed shell with a height direction, solid amine particles enter from a solid amine particle injection pipe at the top of the closed shell, flow from top to bottom by gravity, and are discharged from a solid amine particle discharge pipe at the bottom of the closed shell, carbon dioxide-containing gas enters from a gas inlet pipe at the bottom of the closed shell, and reacts with the solid amine particles flowing from top to bottom during the upward movement in the closed shell, and is then discharged from a gas discharge pipe at the top of the closed shell, a plurality of buffering members capable of vibrating up and down are arranged in the closed shell, the buffering members divide the space in the closed shell into a plurality of chambers, and each buffering member surface has a through hole communicating the two side chambers; the solid amine particles flow through and fill each chamber in turn during the downward flow, and roll by rubbing and touching the buffering members.

[0019] As another optimization scheme of the above-mentioned carbon dioxide recovery system from flue gas, the buffering member is a net-like structure woven by elastic metal wires, and the edges of the net-like structure are directly or through elastic members fixed to the side wall of the closed shell.

[0020] As another optimization scheme of the above-mentioned carbon dioxide recovery system from flue gas, the buffering member is a plate-like member with a surface densely covered with through holes, and the edges of the plate-like member are fixed to the side wall of the closed shell through elastic members.

[0021] As another optimization scheme of the above-mentioned carbon dioxide recovery system from flue gas, the closed shell is provided with a spiral metal wire along the height direction thereof, each buffering member is fixedly connected with the spiral metal wire, the top end of the spiral metal wire is connected with a vibrating piece, the vibrating piece is suspended on the outlet end of the solid amine particle injection pipe through the metal wire, and when the solid amine particles are intermittently discharged, the vibrating piece is impacted on the surface of the vibrating piece, so that the vibrating piece transmits the vibration to each buffering member through the spiral metal wire.

[0022] As another optimization scheme of the carbon dioxide recovery system in flue gas, the carbon dioxide adsorption device comprises at least one group of solid amine adsorption carbon dioxide units, each group of solid amine adsorption carbon dioxide units comprises a closed shell with a height direction, solid amine particles enter from a solid amine particle injection pipe at the top of the closed shell, flow from top to bottom by gravity, and are discharged from a solid amine particle discharge pipe at the bottom of the closed shell; carbon dioxide-containing gas enters from a gas inlet pipe at the bottom of the closed shell, reacts with the solid amine particles flowing from top to bottom during the upward process in the closed shell, and is then discharged from a gas discharge pipe at the top of the closed shell; a plurality of buffering members capable of vibrating up and down under the blowing of the gas are arranged in the closed shell, the buffering members separate the space in the closed shell into a plurality of chambers, the buffering members comprise upper convex pieces and lower concave pieces alternately distributed in the height direction, wherein the upper convex piece is a plate structure with a high center and a low edge, a flow channel is formed between the edge of the upper convex piece and the inner wall of the closed shell, and the upper convex piece is fixed to the side wall of the closed shell through a plurality of elastic members, so that the upper convex piece vibrates up and down when stressed; the lower concave piece is a plate structure with a low center and a high edge, the edge of the lower concave piece is connected with the inner wall of the closed shell, and the center of the lower concave piece has a center channel communicating with adjacent chambers on the upper side and the lower side; the flow channel and the center channel enable the solid amine particles and the gas to react in a baffle form, and the solid amine particles flow through and fill each chamber in turn during the downward flow process, and roll due to friction and contact during the process of impacting the surface of the upper convex piece and flowing along the surface of the upper convex piece.

[0023] As another optimization scheme of the carbon dioxide recovery system in flue gas, the upper surfaces of the upper convex pieces and the lower concave pieces are distributed with a plurality of arc-shaped protrusions.

[0024] As another optimization scheme of the carbon dioxide recovery system in flue gas, the upper surfaces of the upper convex pieces and the lower concave pieces are densely distributed with penetrating holes.

[0025] As another optimization scheme of the carbon dioxide recovery system in flue gas, a spiral metal wire is arranged in the height direction of the closed shell, the spiral metal wire passes through the center channel of the lower concave piece and is fixedly connected with the top highest points of the upper convex pieces, the top highest points of the upper convex pieces are offset from the center positions, the top end of the spiral metal wire is connected with a vibrating piece, the vibrating piece is suspended at the outlet end of the solid amine particle injection pipe through the metal wire, and when the solid amine particles are intermittently discharged, the vibrating piece is impacted on the surface of the vibrating piece, so that the vibrating piece transmits the vibration to each upper convex piece through the spiral metal wire.

[0026] Compared with the prior art, the present application has the following beneficial effects:

[0027] 1) The present application makes the flue gas pass through twice heat exchange and cooling before the flue gas is adsorbed by the solid amine particles, so as to reduce the temperature of the flue gas and facilitate the adsorption by the solid amine particles, and the heat released by the flue gas cooling is used to preheat the solid amine particles which have adsorbed carbon dioxide, so as to gradually increase the temperature of the solid amine particles, thereby further reducing the use amount of steam when using steam heating;

[0028] 2) In the waste heat desorption device and the preheating device of the present application, a plurality of separation pipe layers are arranged, each separation pipe layer is essentially a curvedly arranged flue gas pipe, and in the process of curved arrangement, a gap for the flow of solid amine is also formed, the separation pipe layer forms a plurality of chambers, and in the process of the solid amine particles flowing from top to bottom by gravity, each chamber is sequentially filled, and heat exchange with the flue gas is performed, so as to effectively reduce the temperature of the flue gas and increase the temperature of the solid amine particles; the existence of the separation pipe layer not only reduces the flow speed of the solid amine particles and prolongs the residence time of the solid amine particles in the device, but also effectively increases the overall temperature in the device, so that the temperature uniformity from top to bottom is maintained;

[0029] 3) The carbon dioxide desorption device of the present application, by arranging a concentric separation cylinder in the cylinder, divides the cylinder into a plurality of annular channels, the solid amine particles are heated by contacting with the water vapor from top to bottom in the annular channels, the existence of the annular channels enables the solid amine particles to fully contact with the water vapor, greatly improving the heating efficiency of the water vapor; and by arranging the divergent head, the water vapor can be uniformly sprayed to the bottom of each annular channel, and the gap between the edge and the inner wall of the device reduces the flow speed of the solid amine particles out of the device, prolonging the heating time of the solid amine particles in the device;

[0030] 4) The solid amine carbon dioxide adsorption unit designed in the carbon dioxide adsorption device of the present application, by arranging a special structure buffer member in the solid amine flow channel, not only delays the flow speed of the solid amine particles, prolongs the reaction time of the solid amine particles with the gas, but more importantly, constantly changes the shape of the solid amine particles in the flow process, so that the solid amine particles are in a cycle process of "accumulation-loosening-accumulation-loosening", and in this process, the position of the solid amine particles in the accumulation state also changes, so that the solid amine particles fully react with carbon dioxide, greatly improving the adsorption rate of the solid amine particles;

[0031] The buffer components of this invention, whether mesh structures or plate-like components suspended by elastic elements, are very lightweight and thin. This ensures that they vibrate when impacted by solid amine particles or blown by gas (as gas entry requires a certain pressure and flow rate). During this vibration, the already "accumulated" or "accumulating" solid amine particles are disturbed, disrupting their "accumulation" structure and altering their position. Furthermore, particles in contact with the surface tumble due to friction and contact, changing their flow state and reducing their flow velocity, thus allowing the solid amine particles to fully absorb carbon dioxide. To enhance the vibration of the buffer components, this invention can also incorporate a spiral metal wire connected to each buffer component. The top of the spiral wire is connected to a suspended vibrating plate located at the solid amine particle injection port. During intermittent injection of solid amine particles, the impact on the vibrating plate causes the buffer components to vibrate via the spiral metal wire, thereby changing the flow pattern and position of the solid amine particles in each chamber, allowing them to fully react with the gas.

[0032] The buffer member of the present invention can also be configured as alternating upper convex and lower concave parts along the height direction. A flow channel is formed between the edge of the upper convex part and the inner wall of the shell, and a central channel is formed at the center of the lower concave part. This allows both solid amine particles and gas to flow within the shell in a deflected manner, prolonging the flow path and reaction time. Simultaneously, it disrupts the "aggregation" structure of the solid amine particles, alters their position, and causes particles in contact with their surfaces to tumble due to friction and contact, changing their flow state and reducing their flow velocity. This allows the solid amine particles to fully absorb carbon dioxide. The concave surface is covered with arc-shaped protrusions, which also serve to increase friction and promote changes in particle shape. The spiral metal wire is connected to the top of each upper protrusion, making these upper protrusions form an eccentric structure. The top of the spiral metal wire is connected to a suspended vibrating plate located at the solid amine particle injection port. When solid amine particles are intermittently injected, they impact the vibrating plate, which in turn causes the eccentric upper protrusions to vibrate through the spiral metal wire. This changes the flow pattern and position of the solid amine particles in each chamber, allowing them to fully react with the gas. The eccentric upper protrusions amplify this vibration amplitude. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the system structure of the present invention;

[0034] Figure 2 This is a schematic diagram of the waste heat desorption device and the preheating device;

[0035] Figure 3 for Figure 2 A top view schematic diagram of a type of middle-divided pipe layer structure;

[0036] Figure 4 Structure diagram of carbon dioxide desorption device;

[0037] Figure 5 Structure diagram of one embodiment of solid amine adsorbing carbon dioxide unit in carbon dioxide adsorption device;

[0038] Figure 6 Structure diagram of Figure 5 Structure diagram of one embodiment of magnified A in FIG. 1;

[0039] Figure 7 Structure diagram of Figure 5 Structure diagram of another embodiment of magnified A in FIG. 1;

[0040] Figure 8 Structure diagram of Figure 5 Structure diagram of still another embodiment of magnified A in FIG. 1;

[0041] Figure 9 Structure diagram of another embodiment of solid amine adsorbing carbon dioxide unit in carbon dioxide adsorption device;

[0042] Figure 10 Structure diagram of Figure 9 Structure diagram of magnified B in FIG. 1;

[0043] Figure 11 Structure diagram of still another embodiment of solid amine adsorbing carbon dioxide unit in carbon dioxide adsorption device;

[0044] Figure 12 Structure diagram of Figure 11 Structure diagram of magnified C in FIG. 1;

[0045] Figure 13 Structure diagram of one embodiment of assembling multiple solid amine adsorbing carbon dioxide units into carbon dioxide adsorption device;

[0046] Reference signs: 1, shell, 101, air inlet pipe interface, 102, air distribution pipe, 103, partition pipe layer, 104, exhaust gas collection pipe, 105, exhaust pipe interface, 106, heat exchange chamber, 107, carbon dioxide discharge pipe, 108, first solid amine particle outlet, 109, solid amine particle inlet pipe, 1010, gap, 2, barrel, 201, solid amine particle inlet, 202, second solid amine particle outlet, 203, gas outlet, 204, high-temperature steam inlet pipe, 205, diverging head, 206, partition barrel, 207, annular channel, 3, closed shell, 301, solid amine particle discharge pipe, 302, solid amine particle injection pipe, 303, gas inlet pipe, 304, gas discharge pipe, 305, chamber, 4, buffer member, 401, through hole, 402, vibrating reed, 403, spiral wire, 404, wire, 405, upper protrusion, 406, elastic member, 407, flow channel, 408, lower recess, 409, central channel, 5, outer shell, 501, air inlet manifold, 502, feedstock inlet manifold, 503, water injection pipe, 504, overflow pipe, 505, cooling channel, 6, solid amine particle collection chamber, 601, discharge port, 7, gas collection chamber, 701, exhaust port. DETAILED DESCRIPTION

[0047] The technical solutions of the present application will be further described in detail below in combination with specific embodiments. The parts not described in the following embodiments of the present application, such as the filter impurity removal device, desulfurization and denitrification device, composition, size of the solid amine particles, adsorption and desorption mechanism of carbon dioxide (such as the contents disclosed in the application number 2021106156225, a carbon dioxide adsorbent and its preparation method and application), and the speed and flow rate of the solid amine particles entering the solid amine particle injection pipe, whether gas flow assistance is needed, the flow rate and flow rate of the gas when entering, and the need for gas flow assistance when the solid amine particles are transferred in the system, are all considered as prior art known or should be known by those skilled in the art.

[0048] Example 1

[0049] A method for recovering carbon dioxide from flue gas, as shown in Figure 1 , comprising the following steps:

[0050] 1) The high-temperature flue gas is filtered to remove impurities to remove internal dust impurities, becoming impurity-removed flue gas, the temperature of the impurity-removed flue gas is not more than 350℃, then the impurity-removed flue gas and the solid amine particles for adsorbing carbon dioxide undergo first heat exchange, part of the solid amine particles desorb carbon dioxide by heating, the cooled flue gas is subjected to desulfurization and denitrification treatment to form clean flue gas;

[0051] 2) The clean flue gas exchanges heat with the solid amine particles that adsorb carbon dioxide for the second time, forming low-temperature flue gas that exchanges heat with the solid amine particles, and the flue gas after adsorption is discharged, and the temperature of the low-temperature flue gas is generally not more than 60℃;

[0052] 3) The solid amine particles that have reacted and adsorbed carbon dioxide first exchange heat with the clean flue gas in step 2) to increase the temperature, and then exchange heat with the impure flue gas in step 1) to further increase the temperature;

[0053] 4) The solid amine particles after being heated in step 3) are introduced into high-temperature water vapor with a temperature of 110-140℃, so that the solid amine particles desorb the adsorbed carbon dioxide, the desorbed carbon dioxide is compressed and stored after being dehumidified, and the ratio of the amount of water vapor introduced to the solid amine particles is determined by experiments according to actual conditions; the solid amine particles are cooled and returned to step 2) to exchange heat with the low-temperature flue gas.

[0054] Example 2

[0055] A carbon dioxide recovery system in flue gas, as shown in Figure 1 , includes a filtering and impurity removing device, a waste heat desorption device, a desulfurization and denitrification device, a preheating device, a carbon dioxide adsorption device, and a carbon dioxide desorption device. The filtering and impurity removing device and the desulfurization and denitrification device can use existing flue gas filtering and dust removing devices and desulfurization and denitrification devices, which are not described in detail. High-temperature flue gas first passes through the filtering and impurity removing device to remove solid particle impurities contained therein, and the resulting impure flue gas releases heat in the waste heat desorption device, and then passes through the desulfurization and denitrification device to remove sulfur oxides and nitrogen oxides, and the resulting clean flue gas is introduced into the preheating device to release heat again, and the resulting low-temperature flue gas is introduced into the carbon dioxide adsorption device to exchange heat with the solid amine particles. The solid amine particles that have adsorbed carbon dioxide first absorb heat in the preheating device, and then are introduced into the waste heat desorption device to be heated again, and finally are introduced into the carbon dioxide desorption device to be heated directly by high-temperature water vapor. The solid amine particles after desorption of carbon dioxide are cooled by the particle cooling device and then are introduced into the carbon dioxide adsorption device again. The mixed gas of carbon dioxide and water vapor is first cooled and dehumidified, and the remaining carbon dioxide is compressed and stored.

[0056] In this embodiment, the particle cooling device is a device for reducing the temperature of the solid amine particles, which can use natural cooling or heat exchange to reduce the temperature of the solid amine particles. When heat exchange is used, air or water is used as the cooling medium, and the cooling medium does not directly contact the solid amine particles to reduce the temperature of the solid amine particles.

[0057] Example 3

[0058] This embodiment is an optimized scheme for the structure of the waste heat analysis device and the preheating device based on embodiment 2, and the main structure is the same as that of embodiment 2. The improvement lies in that the waste heat analysis device and the preheating device are of the same structure, as shown in Figure 2 The shell 1 is generally cylindrical, and of course can be made into other shapes with a horizontal cross section of a rectangle or a regular polygon, as long as it has a certain height to meet the requirement that the solid amine particles flow and discharge from top to bottom for a certain time. The top of the shell 1 is generally arc-shaped, and the carbon dioxide discharge pipe 107 is located at the arc-shaped top, and the solid amine particle inlet pipe 109 is arranged on one side of the carbon dioxide discharge pipe 107. The solid amine particle inlet pipe 109 is generally inclined, so that the solid amine particles can flow into the shell 1 automatically by gravity. A plurality of partition pipe layers 103 are arranged inside the shell 1, which divide the shell 1 into a plurality of heat exchange chambers 106 from top to bottom. The height of each heat exchange chamber 106 is generally not high, and the finally formed heat exchange chamber 106 is a flat cylindrical structure. Each of the partition pipe layers 103 is a layered structure formed by bending a flue gas pipe and having a gap 1010, as shown in Figure 3 The left and right structures are symmetrical, and a plurality of semi-annular pipes (half of the annular pipe) are formed from outside to inside on the left half, and the gap 1010 for the solid amine particles to pass through is formed between the adjacent two layers of semi-annular pipes. The center of the outermost circle is in communication with the outside, and the end of the semi-annular pipe adjacent to the inside of the outermost circle is in communication with the center of the semi-annular pipe inside the outermost circle. The center of the semi-annular pipe is in communication with the center of the semi-annular pipe inside the outermost circle, and so on. Adjacent two heat exchange chambers 106 are in communication through the gap 1010. After the solid amine particles enter the shell 1 from the solid amine particle inlet pipe 109, they are heated by heat exchange with the flue gas flowing in the partition pipe layer 103 during the process of passing through the heat exchange chambers 106 in sequence, and finally discharged from the first solid amine particle outlet 108. The carbon dioxide gas resolved by the heated solid amine particles is discharged from the carbon dioxide discharge pipe 107 and collected. The gas inlet distribution pipe 102 with a gas inlet pipe interface 101 and the gas outlet gathering pipe 104 with a gas outlet pipe interface 105 are symmetrically arranged outside the shell 1. One end of all the flue gas pipes forming the partition pipe layer 103 is in communication with the gas inlet distribution pipe 102, and the other end is in communication with the gas outlet gathering pipe 104.

[0059] Embodiment 4

[0060] This embodiment is an optimized scheme for the structure of the waste heat analysis device and the preheating device based on embodiment 2, and the main structure is the same as that of embodiment 2. The improvement lies in that the waste heat analysis device and the preheating device are of the same structure, as shown in Figure 4As shown, the cylinder 2 is generally cylindrical, of course, can also be made into a horizontal cross-section of the rectangle, regular polygon other shapes, as long as it has a certain height, to meet the solid amine particles from top to bottom to spend some time to flow out, the top and bottom of the cylinder 2 are arc-shaped, the top of the cylinder 2 is provided with a gas outlet 203 and a solid amine particles into the port 201, the gas outlet 203 is at the top of the arc-shaped, the solid amine particles into the port 201 is generally in the side of the circular arc, generally horizontal or slightly inclined downward angle to the top of the cylinder 2 into the solid amine particles, the bottom of the cylinder 2 has a second solid amine particles outlet 202 and a high-temperature vapor inlet pipe 204, the second solid amine particles outlet 202 is at the lowest point of the bottom arc, the high-temperature vapor inlet pipe 204 is at the side of the arc and enters horizontally, the inside of the cylinder 2 has a plurality of open ends and concentric with the cylinder 2 of the separation cylinder 206, the separation cylinder 206 is a thin-walled structure of the ring made of metal material, these separation cylinders 206 divide the cylinder 2 into a plurality of annular channels 207, the height of the annular channel 207 is equal to the straight cylinder segment of the cylinder 2, thereby forming a space between the top and bottom arc structure; the solid amine particles discharged by the solid amine particles into the port 201 flow along the annular channel 207 from top to bottom, in the process, the high-temperature vapor inlet pipe 204 is provided with a semicircular diverging head 205 at one end of the cylinder 2, the diverging head 205 is a hollow structure, which has a circular arc-shaped upper surface, and the upper surface is uniformly distributed with gas injection holes, the edge of the diverging head 205 and the arc-shaped structure sidewall of the bottom of the cylinder 2 form a channel for the flow of solid amine particles, the solid amine particles flow through the channel after being buffered on the upper surface of the diverging head 205, and are discharged from the second solid amine particles outlet 202, the diverging head 205 uniformly sprays high-temperature vapor to the bottom of all annular channels 207, and heats the solid amine particles during the rising process along the annular channel 207, the separated carbon dioxide and water vapor are discharged from the gas outlet 203, and the solid amine particles are discharged from the second solid amine particles outlet 202.

[0061] Example 5

[0062] This embodiment is a preferred scheme for the carbon dioxide adsorption device based on example 2, the main structure is the same as example 2, the improvement point is that: the carbon dioxide adsorption device comprises at least one group of solid amine adsorption carbon dioxide unit, each group of solid amine adsorption carbon dioxide unit comprises a closed shell 3 with a height direction extension, such as Figure 5As shown, the closed shell 3 is generally cylindrical, of course, can also be made into horizontal section is rectangular, regular polygon other shape, as long as it has a certain height, meet the solid amine particles from top to bottom spend a certain time flow discharge can, solid amine particles from the solid amine particles injection pipe 302 into the top of the closed shell 3, the top of the closed shell 3 is generally arc-shaped, at this time, the solid amine particles injection pipe 302 is generally in the arc-shaped side, generally horizontal or slightly inclined downward angle to the top of the closed shell 3 into the solid amine particles, solid amine particles rely on gravity from top to bottom flow, from the solid amine particles discharge pipe 301 at the bottom of the closed shell 3 discharge, the bottom of the closed shell 3 is also arc-shaped, the solid amine particles discharge pipe 301 is in the lowest arc-shaped, carbon dioxide containing gas from the gas into the pipe 303 into the bottom of the closed shell 3, in order to ensure the effect of reaction and adsorption, the gas into the pipe 303 is generally open in the middle of the solid amine particles discharge pipe 301 side, and in the process of rising in the closed shell 3 with the flow from top to bottom of the solid amine particles reaction, then from the gas discharge pipe 304 at the top of the closed shell 3 discharge, the gas discharge pipe 304 is in the highest arc-shaped at the top of the closed shell 3, so as to facilitate the automatic discharge of the gas after adsorption, the closed shell 3 is provided with a plurality of buffering members 4 which can vibrate up and down, the buffering member 4 is light enough in weight, thin enough in thickness, these buffering members 4 divide the space in the closed shell 3 into a plurality of chambers 305, these chambers 305 are distributed from top to bottom along the inside of the closed shell 3, the height of each chamber 305 can be adjusted and set according to actual needs, the surface of each buffering member 4 has a through hole 401 which communicates the two chambers 305 on both sides, as shown in Figure 6 The diameter of the through hole 401 is generally 4-6 times the diameter of the solid amine particles, a large number of solid amine particles will rub and slow down when passing through, thereby reducing the passing speed; the solid amine particles flow through and fill each chamber 305 in turn during the flow from top to bottom, rub and touch the buffering member 4 to roll over, change the flow state and reduce the flow speed, so that the solid amine particles can fully absorb carbon dioxide.

[0063] In this embodiment, the buffering member 4 can be a net-like structure woven by elastic metal wires, the edge of the net-like structure is directly or through the elastic member 406 fixed on the side wall of the closed shell 3, as shown in Figure 7 The elastic member 406 is a spring, and the installation position of the spring is higher than the height of the buffering member 4, so as to hang up the buffering member 4.

[0064] In this embodiment, the buffering member 4 can be a plate-like member with a large number of through holes 401 on the surface, the plate-like member is light enough in weight and thin enough in thickness, and the edge thereof is fixed on the side wall of the closed shell 3 through the elastic member 406, as shown in Figure 7As shown, the elastic member 406 is a spring, and the mounting position of the spring is higher than the height of the buffer member 4, thereby lifting the buffer member 4.

[0065] Embodiment 6

[0066] This embodiment is an improved scheme based on embodiment 5, and the main structure is the same as that of embodiment 5, and the improvement lies in that, as shown in Figure 8 As shown, the middle part of the closed shell 3 is provided with a spiral metal wire 403 in the height direction thereof, the spiral metal wire 403 is spirally downward, the middle area of each buffer member 4 is fixedly connected with the spiral metal wire 403, the top end of the spiral metal wire 403 is connected with a vibrating plate 402, the vibrating plate 402 is light enough in weight and thin enough in thickness, the vibrating plate 402 is suspended at the outlet end of the solid amine particle injection pipe 302 through a metal wire 404, and when the solid amine particle injection pipe 302 intermittently discharges the solid amine particles, the vibrating plate 402 is impacted by the solid amine particles to vibrate itself, and the vibration is transmitted to each buffer member 4 through the spiral metal wire 403; the preferred suspension position of the metal wire 404 is at the lower end position of the gas discharge pipe 304.

[0067] Embodiment 7

[0068] This embodiment is another preferred scheme of the carbon dioxide adsorption device based on embodiment 2, and the main structure is the same as that of embodiment 2, and the improvement lies in that: the carbon dioxide adsorption device comprises at least one group of solid amine adsorption carbon dioxide units, each group of solid amine adsorption carbon dioxide units comprises a closed shell 3 extending in the height direction, as shown in Figure 9As shown, the closed shell 3 is generally cylindrical, of course, it can also be made into other shapes with horizontal section being rectangular, regular polygon, as long as it has a certain height, meets the solid amine particles flowing out from top to bottom for a certain time, the solid amine particles enter from the solid amine particle injection pipe 302 at the top of the closed shell 3, the top of the closed shell 3 is generally arc-shaped, at this time, the solid amine particle injection pipe 302 is generally at the side of the arc shape, generally horizontally or slightly inclined downward to inject solid amine particles into the top of the closed shell 3, the solid amine particles flow from top to bottom by gravity, and are discharged from the solid amine particle discharge pipe 301 at the bottom of the closed shell 3, the bottom of the closed shell 3 is also arc-shaped, and the solid amine particle discharge pipe 301 is at the lowest point of the arc shape, the gas containing carbon dioxide enters from the gas inlet pipe 303 at the bottom of the closed shell 3, in order to ensure the effect of reaction and adsorption, the gas inlet pipe 303 is generally opened at the side of the middle part of the solid amine particle discharge pipe 301, and reacts with the solid amine particles flowing from top to bottom during the rising process in the closed shell 3, and then is discharged from the gas discharge pipe 304 at the top of the closed shell 3, the gas discharge pipe 304 is at the highest point of the arc shape at the top of the closed shell 3, so as to facilitate the automatic discharge of the adsorbed gas, a plurality of buffer members 4 capable of vibrating up and down under the blowing of the gas are arranged in the closed shell 3, the buffer members 4 are light in weight and thin in thickness, these buffer members 4 divide the space in the closed shell 3 into a plurality of chambers 305, these chambers 305 are distributed from top to bottom inside the closed shell 3, the buffer members 4 include upper convex pieces 405 and lower concave pieces 408 which are alternately distributed along the height direction, the distance between the upper convex pieces 405 and the lower concave pieces 408 (i.e. the height of the chamber 305) is adjusted and set according to actual needs, the alternately distributed means that, as shown in the figure, Figure 10As shown, from top to bottom in the height direction, the first is the upper convex piece 405, the second is the lower concave piece 408, the third is still the upper convex piece 405, and the fourth is the lower concave piece 408. Arranged in this order, the bottom one is preferably the lower concave piece 408. The shapes of the upper convex piece 405 and the lower concave piece 408 are preferably conical, and the cone top angle is generally 140-170°. The upper convex piece 405 is a plate-shaped structure with a high center and a low edge. It is light enough in weight and thin enough in thickness. A flow channel 407 is formed between the edge of the upper convex piece 405 and the inner wall of the closed shell 3. The width of the flow channel 407 is generally 5-10 times the diameter of the solid amine particles. The upper convex piece 405 is fixed to the side wall of the closed shell 3 by a plurality of elastic members 406, so that it can vibrate up and down when subjected to force. The elastic members 406 are springs, and the installation position of the springs is higher than the height of the upper convex piece 405, so that the upper convex piece 405 is suspended. The number of elastic members 406 is generally 3 or 4, and they are evenly distributed. The lower concave piece 408 is a plate-shaped structure with a low center and a high edge. It is light enough in weight and thin enough in thickness. The edge of the lower concave piece 408 is connected to the inner wall of the closed shell 3. The connection between the edge of the lower concave piece 408 and the inner wall of the closed shell 3 can be welding or movable connection through elastic material. The center has a central passage 409 that connects the adjacent chambers 305 on the upper and lower sides. The central passage 409 is generally circular, and its diameter is generally 5-10 times the diameter of the solid amine particles. The flow channel 407 and the central passage 409 make the solid amine particles and the gas react in a baffle form. During the downward flow of the solid amine particles, they flow through and fill each chamber 305 in turn. During the impact on the surface of the upper convex piece 405 and the flow along the surface, the solid amine particles roll due to friction and contact, change their flow state, and reduce their flow speed, so that the solid amine particles can fully absorb carbon dioxide.

[0069] In this embodiment, the upper surfaces of the upper convex piece 405 and the lower concave piece 408 can be smooth planes, or can have a plurality of arc-shaped protrusions distributed thereon. The arc-shaped protrusions are used to increase the roughness of the upper surfaces of the upper convex piece 405 and the lower concave piece 408, so as to slow down the flow speed of the solid amine particles. The maximum height of the arc-shaped protrusions is generally not more than 1 / 5 of the diameter of the solid amine particles.

[0070] In this embodiment, the upper convex piece 405 and the lower concave piece 408 can be complete plate-shaped pieces, or can have a plurality of through holes 401 densely distributed thereon. The diameter of the through holes 401 is generally 4-6 times the diameter of the solid amine particles. A large number of solid amine particles will rub and slow down when passing through the through holes 401, thereby reducing the passing speed.

[0071] Embodiment 8

[0072] This embodiment is an improved scheme based on embodiment 7. The main structure is the same as that of embodiment 7. The improvement lies in that: Figure 11As shown, the middle part of the closed shell 3 is provided with a spiral wire 403 along its height direction, the spiral wire 403 passes through the central passage 409 of the lower concave part 408 and is fixedly connected with the top highest point of each upper convex part 405, and the top highest point of the upper convex part 405 is offset from the center position, at this time, all the upper convex parts 405 form an eccentric conical shape with the top highest point not on the same vertical axis, like Figure 12 As shown, the top end of the spiral wire 403 is connected with a vibrating plate 402, the vibrating plate 402 is light enough in weight and thin enough in thickness, the vibrating plate 402 is suspended at the outlet end of the solid amine particle injection pipe 302 through the metal wire 404, and when the solid amine particle injection pipe 302 intermittently discharges the solid amine particles, the solid amine particles impact on the surface of the vibrating plate 402 to make the vibrating plate 402 vibrate, and the vibrating plate 402 transmits the vibration to each upper convex part 405 through the spiral wire 403.

[0073] Example 9

[0074] This embodiment is an improvement on the carbon dioxide adsorption device in example 5, example 6, example 7 and example 8, the core of which is to compound multiple groups of solid amine adsorption carbon dioxide units in example 5, example 6, example 7 or example 8 to improve the adsorption efficiency, and the specific structure is as follows Figure 13As shown, it comprises a closed shell 5, the shell 5 is internally a cavity structure, the shell 5 is generally cylindrical, rectangular or regular polygon structure, a plurality of solid amine adsorption carbon dioxide units in embodiments 5, 6, 7 or 8 are vertically arranged in the shell 5 along its height direction, and cooling channels 505 are formed between the solid amine adsorption carbon dioxide units, a plurality of horizontal fixing members are generally arranged in the shell 5, which are used to fix the solid amine adsorption carbon dioxide units to the inner wall of the shell 5 and fix adjacent solid amine adsorption carbon dioxide units, the bottom and one side of the top of the shell 5 are respectively provided with a water injection pipe 503 for injecting cooling water into the shell 5 and an overflow pipe 504 for automatically discharging cooling water in the shell 5 by overflow, the cooling water enters the shell 5 from the water injection pipe 503 at the bottom and fills the cooling channels 505, with the water level rising, the outer walls of all solid amine adsorption carbon dioxide units are covered and cooled, providing a low-temperature environment for the solid amine adsorption carbon dioxide, and finally flowing out from the overflow pipe 504 at the top, the top of the shell 5 is provided with a gas gathering cavity 7, which is a circular cone with a wide bottom and a narrow top, and an open exhaust port 701 at the top, the gas gathering cavity 7 is communicated with the gas discharge pipe 304 of each solid amine adsorption carbon dioxide unit and discharges through the exhaust port 701 at the top; the bottom of the shell 5 is provided with a solid amine particle gathering cavity 6, which is an inverted circular cone with a wide top and a narrow bottom, and a discharge port 601 is arranged at the lowest part of the bottom, the solid amine particle gathering cavity 6 is communicated with the solid amine particle discharge pipe 301 of each solid amine adsorption carbon dioxide unit and discharges through the discharge port 601 at the bottom; the gas inlet pipe 303 of all solid amine adsorption carbon dioxide units is communicated with a gas inlet main pipe 501, the gas inlet main pipe 501 is communicated with a gas source after extending out of the shell 5, and the solid amine particle injection pipe 302 of all solid amine adsorption carbon dioxide units is communicated with a feeding main pipe 502, the feeding main pipe 502 is communicated with a solid amine particle storage bin after extending out of the shell 5.

Claims

1. A system for recovering carbon dioxide from flue gas, comprising a filtering and impurity removing device, a waste heat desorption device, a desulfurization and denitrification device, a preheating device, a carbon dioxide adsorption device, and a carbon dioxide desorption device, wherein, The high-temperature flue gas first passes through a filtering and impurity removing device to remove solid particle impurities contained therein, the impurity-removed flue gas releases heat in a waste heat resolution device, then passes through a desulfurization and denitration device to remove sulfur oxides and nitrogen oxides, the clean flue gas releases heat again in a preheating device, and finally enters a carbon dioxide adsorption device to react with solid amine particles, characterized in that: the solid amine particles that have adsorbed carbon dioxide first absorb heat in the preheating device, then are sent into the waste heat resolution device to be heated again, and finally are heated directly by high-temperature water vapor in the carbon dioxide resolution device, the solid amine particles after resolution of carbon dioxide are cooled by a particle cooling device and then are sent into the carbon dioxide adsorption device again. The carbon dioxide adsorption device comprises at least one set of solid amine carbon dioxide adsorption units, each set of solid amine carbon dioxide adsorption units comprises a closed shell (3) extending in the height direction, solid amine particles enter from a solid amine particle injection pipe (302) at the top of the closed shell (3), flow from top to bottom by gravity, and are discharged from a solid amine particle discharge pipe (301) at the bottom of the closed shell (3), carbon dioxide-containing gas enters from a gas inlet pipe (303) at the bottom of the closed shell (3), reacts with the solid amine particles flowing from top to bottom in the closed shell (3) during the upward process, and is then discharged from a gas discharge pipe (304) at the top of the closed shell (3), a plurality of buffer members (4) capable of vibrating up and down are arranged in the closed shell (3), the buffer members (4) divide the space in the closed shell (3) into a plurality of chambers (305), each buffer member (4) comprises upper convex pieces (405) and lower concave pieces (408) alternatingly distributed in the height direction, wherein the upper convex piece (405) is a plate-shaped structure with a high center and a low edge, a flow channel (407) is formed between the edge of the upper convex piece (405) and the inner wall of the closed shell (3), and the upper convex piece (405) is fixed to the side wall of the closed shell (3) by a plurality of elastic members (406), so as to vibrate up and down when subjected to force; the lower concave piece (408) is a plate-shaped structure with a low center and a high edge, the edge of the lower concave piece (408) is connected with the inner wall of the closed shell (3), and the center has a center passage (409) communicating with the adjacent chambers (305) on the upper side and the lower side thereof; the flow channel (407) and the center passage (409) enable the solid amine particles and the gas to react in a baffle form, in the process of flowing from top to bottom, the solid amine particles flow through and fill each chamber (305) in turn, and tumble due to friction and collision in the process of impacting the surface of the upper convex piece (405) and flowing along the surface.

2. A system for recovering carbon dioxide from a flue gas according to claim 1, characterized in that: The waste heat resolution device and the preheating device have the same structure, comprising a shell (1) having a carbon dioxide discharge pipe (107) and a first solid amine particle outlet (108) at the top and the bottom, respectively, and a solid amine particle inlet pipe (109) arranged at one side of the carbon dioxide discharge pipe (107); the inside of the shell (1) is provided with a plurality of partition pipe layers (103), which divide the shell (1) into a plurality of heat exchange chambers (106) from top to bottom, each of the partition pipe layers (103) is a layered structure formed by bending a flue gas pipe and having a gap (1010), and the adjacent two heat exchange chambers (106) are communicated through the gap (1010); after the solid amine particles enter the shell (1) from the solid amine particle inlet pipe (109), they are heated by heat exchange with the flue gas flowing in the partition pipe layers (103) in the process of passing through the heat exchange chambers (106) in turn, and finally discharged from the first solid amine particle outlet (108); the carbon dioxide gas resolved by the heating of the solid amine particles is discharged from the carbon dioxide discharge pipe (107) and collected; an air inlet distribution pipe (102) having an air inlet pipe interface (101) and an air outlet gathering pipe (104) having an air outlet pipe interface (105) are symmetrically arranged outside the shell (1), respectively; one end of all the flue gas pipes forming the partition pipe layers (103) is communicated with the air inlet distribution pipe (102), and the other end is communicated with the air outlet gathering pipe (104).

3. A system for recovering carbon dioxide from a flue gas according to claim 1, characterized in that: The carbon dioxide resolution device comprises a cylinder (2), a gas outlet (203) and a solid amine particle inlet (201) are arranged at the top of the cylinder (2), a second solid amine particle outlet (202) and a high-temperature vapor inlet pipe (204) are arranged at the bottom of the cylinder (2), a plurality of partition cylinders (206) having two open ends and being concentric with the cylinder (2) are arranged in the inside of the cylinder (2), the partition cylinders (206) divide the inside of the cylinder (2) into a plurality of annular channels (207), the solid amine particles discharged from the solid amine particle inlet (201) flow along the annular channels (207) from top to bottom, in the process, a half-round diverging head (205) is arranged at one end of the cylinder (2) at the high-temperature vapor inlet pipe (204), the diverging head (205) uniformly sprays high-temperature vapor to the bottom of all the annular channels (207), and heats the solid amine particles in the process of rising along the annular channels (207), the resolved carbon dioxide and water vapor are discharged from the gas outlet (203), and the solid amine particles are discharged from the second solid amine particle outlet (202).

4. A system for recovering carbon dioxide from a flue gas according to claim 1, characterized in that: The upper surfaces of the upper convex piece (405) and the lower concave piece (408) are distributed with a plurality of arc-shaped protrusions.

5. A system for recovering carbon dioxide from a flue gas according to claim 1, characterized in that: The upper convex piece (405) and the lower concave piece (408) are densely covered with through holes (401).

6. A system for recovering carbon dioxide from a flue gas according to claim 1, characterized in that: Said closed shell (3) is provided with a spiral metal wire (403) along its height direction, the spiral metal wire (403) passes through the central passage (409) of the lower concave part (408), and is fixedly connected with the top highest point of each upper convex part (405), and makes the top highest point of the upper convex part (405) deviate from the central position, the top end of the spiral metal wire (403) is connected with a vibrating plate (402), the vibrating plate (402) is suspended at the outlet end of the solid amine particle injection pipe (302) through the metal wire (404), and when the solid amine particles are intermittently discharged, the vibrating plate (402) is impacted on the surface, so that the vibration is transmitted to each upper convex part (405) through the spiral metal wire (403).

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