Recycling system for carbon dioxide in baking soda carbonization tower process tail gas

Abstract

A system for recycling carbon dioxide in process tail gas of a baking soda carbonization tower comprises a separation and purification subsystem which can be used for separating and purifying carbon dioxide in tail gas discharged by the carbonization tower and generating gas with the carbon dioxide concentration of 35%-65% for recycling; and the compression subsystem is used for compressing the tail gas so as to provide kinetic energy for separation and purification of the tail gas, is arranged at the process upstream of the separation and purification subsystem and is connected with the separation and purification subsystem. The system provided by the invention can be used for carrying out multiple process operations such as air induction, heat exchange, pretreatment, compression, purification, preheating and returning to the carbonization tower on the discharged tail gas, and the purified tail gas can be used as raw material gas. According to the invention, purification, concentration, purification and reutilization of tail gas are realized, and addition of carbon dioxide gas as a carbonization reaction raw material can be reduced, so that the productivity of upstream calcined limestone is saved, energy consumption is reduced, tail gas emission is reduced, and environmental pollution and resource waste are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field related to industrial tail gas treatment, and more specifically, particularly relates to a system for recovering and utilizing carbon dioxide in tail gas from a baking soda carbonization tower process. Background Art

[0002] Baking soda is a refined product in the production of soda ash. Currently, the production process of baking soda includes a carbonization reaction process, and the carbonization of baking soda uses kiln gas, that is, 40% concentration of carbon dioxide, to carbonize and make alkali. The content (concentration) of carbon dioxide in the tail gas produced after the carbonization of baking soda is generally 12%-20%, or even higher, which results in the effective utilization rate of kiln gas being only about 60%, which is undoubtedly a loss for the production consumption of baking soda.

[0003] In addition, in the prior art, the tail gas generated after the carbonization of baking soda will be directly discharged into the chimney, which contains carbon dioxide at a concentration of up to 12%-20%, which not only pollutes the environment but also causes a waste of resources. Summary of the invention

[0004] 1. Technical issues

[0005] In summary, how to effectively recycle and utilize the carbon dioxide generated by the baking soda carbonization process to solve problems such as resource waste and environmental pollution has become an urgent problem to be solved by technical personnel in this field.

[0006] (II) Technical solution

[0007] The present invention provides a system for recovering and utilizing carbon dioxide in tail gas from a baking soda carbonization tower process. In the present invention, the system for recovering and utilizing carbon dioxide in tail gas from a baking soda carbonization tower process comprises:

[0008] A separation and purification subsystem for PSA purification of tail gas, through which the carbon dioxide in the tail gas discharged from the carbonization tower can be separated and purified, and a gas with a carbon dioxide concentration of 35%-65% can be generated for reuse;

[0009] A compression subsystem for compressing tail gas to provide kinetic energy for separation and purification of tail gas, wherein the compression subsystem is arranged upstream of the separation and purification subsystem and connected to the separation and purification subsystem.

[0010] Preferably, the carbon dioxide recovery and utilization system in the baking soda carbonization tower process tail gas provided by the present invention also includes a pretreatment subsystem, which pretreats the tail gas discharged from the carbonization tower, and the pretreatment includes particulate impurity separation, gas water washing and water separation.

[0011] Preferably, in the carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process provided by the present invention, the pretreatment subsystem includes an impurity absorption device for washing the tail gas with water and removing water-soluble impurities in the tail gas by water washing; the pretreatment subsystem includes a cyclone separator for cyclone separation of particulate impurities and water droplets in the tail gas by cyclone separation; the pretreatment subsystem includes a drying device for drying the tail gas; the impurity absorption device, the cyclone separator and the drying device are connected in sequence.

[0012] Preferably, in the carbon dioxide recovery and utilization system in the baking soda carbonization tower process tail gas provided by the present invention, the impurity absorption equipment includes a vertically arranged tank structure, the top of the tank structure is used to discharge the treated gas, a spray pipe is arranged inside the tank structure, a gas inlet is arranged on the side wall of the tank structure, the gas inlet is arranged close to the lower end of the tank structure, the spray pipe is arranged close to the upper end of the tank structure, and the impurity absorption equipment discharge pipe is arranged at the bottom end of the tank structure.

[0013] Preferably, in the carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process provided by the present invention, the pretreatment subsystem also includes an absorbent circulation device and a deposited alkali solution recovery device for treating the separated substances produced by the tail gas pretreatment; the impurity absorption equipment discharge pipe is connected to the deposited alkali solution recovery device, and the absorbent circulation device is connected to the deposited alkali solution recovery device to provide power for alkali solution recovery.

[0014] Preferably, in the carbon dioxide recovery and utilization system in the baking soda carbonization tower process tail gas provided by the present invention, the cyclone separator is connected to the drying device, and the compression subsystem is arranged between the cyclone separator and the drying device; the drying device is a cold dryer or a dryer.

[0015] Preferably, in the carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process provided by the present invention, a vacuum pump is connected to the separation and purification subsystem, and a product gas holding tank is connected through the vacuum pump.

[0016] Preferably, the carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process provided by the present invention also includes a heat exchange subsystem, which includes a main heat exchanger, a tail gas heat exchange unit and a compressor heat exchange unit. The tail gas heat exchange unit is arranged on the tail gas discharge port of the carbonization tower, and is used to cool the high-temperature tail gas discharged from the carbonization tower and recover the tail gas heat energy. The compressor heat exchange unit is arranged at the exhaust port of the compressor, and is used to cool the high-temperature compressed gas output by the compressor and recover the compressed gas heat energy. The tail gas heat exchange unit and the compressor heat exchange unit are both connected to the main heat exchanger and are used to transport the absorbed heat energy to the main heat exchanger; the main heat exchanger is provided with a heat absorption pipeline, and the main heat exchanger preheats the treated high carbon dioxide concentration gas and can return the heat absorption pipeline to the carbonization tower for reuse.

[0017] Preferably, the carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process provided by the present invention also includes an induced draft subsystem, the induced draft subsystem includes a blower, the blower is connected to the tail gas discharge port of the carbonization tower, a buffer tank is connected to the air outlet of the blower, the buffer tank is connected to the pretreatment subsystem, and a buffer tank discharge outlet is arranged at the bottom of the buffer tank.

[0018] Preferably, the carbon dioxide recovery and utilization system in the baking soda carbonization tower process tail gas provided by the present invention also includes a control subsystem, the control subsystem includes a controller and a solenoid valve, the controller is controlled and connected with each subsystem and the solenoid valve in the system, and the solenoid valve is arranged on the connecting pipeline between the equipment in each subsystem; the separation and purification subsystem includes multiple (two or more) PSA separation and purification units.

[0019] (III) Beneficial effects

[0020] As can be seen from the above, the present invention provides a carbon dioxide recovery and utilization system in the tail gas of a baking soda carbonization tower process. In the present invention, the system includes: a separation and purification subsystem for PSA purification of tail gas, through which the carbon dioxide in the tail gas discharged from the carbonization tower can be separated and purified, and a gas with a carbon dioxide concentration of 35%-65% can be generated for reuse; a compression subsystem for compressing the tail gas to provide kinetic energy for the separation and purification of the tail gas, the compression subsystem is arranged at the process upstream of the separation and purification subsystem and connected to the separation and purification subsystem. In order to solve the many problems existing in the emission of tail gas with high carbon dioxide content, the present invention provides a carbon dioxide recovery and utilization system in the tail gas of a baking soda carbonization tower process. Through the above structural design, the system provided by the present invention can perform multiple process operations such as induced draft-heat exchange-pretreatment-compression-purification on the discharged tail gas and then return it to the carbonization tower, so that the purified tail gas (with a higher carbon dioxide concentration in the gas, the concentration is close to 40%) can be used as raw gas. Through the overall design of the system, the present invention realizes the concentration, purification and reuse of tail gas. The present invention can reduce the addition of carbon dioxide gas as a raw material for the carbonization reaction, thereby saving the production capacity of upstream calcined limestone, saving energy consumption, reducing tail gas emissions, and reducing environmental pollution and waste of resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The present invention is a simplified schematic diagram of the structure of a system for recovering and utilizing carbon dioxide in the tail gas of a baking soda carbonization tower process in one embodiment of the present invention.

[0022] exist Figure 1 In the figure, the corresponding relationship between the component names and the reference numerals is as follows:

[0023] Compression subsystem 1, impurity absorption equipment 2, cyclone separator 3, drying device 4, spray pipe 5, impurity absorption equipment drain pipe 6, absorbent circulation device 7, sedimentation alkali solution recovery device 8, vacuum pump 9, product gas holding tank 10, main heat exchanger 11, blower 12, buffer tank 13, PSA separation and purification unit 14. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0025] In addition, in the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, it can be a fixed connection or a detachable connection; it can be directly connected or indirectly connected through an intermediate component. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0026] Please refer to Figure 1 , Figure 1 The present invention is a simplified schematic diagram of the structure of a system for recovering and utilizing carbon dioxide in the tail gas of a baking soda carbonization tower process in one embodiment of the present invention.

[0027] The present invention provides a system for recovering and utilizing carbon dioxide in tail gas from a baking soda carbonization tower process. In the present invention, the system for recovering and utilizing carbon dioxide in tail gas from a baking soda carbonization tower process mainly comprises: 1. a separation and purification subsystem for performing PSA purification on tail gas, through which the carbon dioxide in the tail gas discharged from the carbonization tower can be separated and purified, and a gas with a carbon dioxide concentration of 35%-65% can be generated for reuse; 2. a compression subsystem 1 for compressing the tail gas to provide kinetic energy for the separation and purification of the tail gas, wherein the compression subsystem 1 is arranged at the process upstream of the separation and purification subsystem and is connected to the separation and purification subsystem.

[0028] The carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process provided by the present invention specifically includes a compression subsystem 1, an impurity absorption device 2, a cyclone separator 3, a drying device 4, a spray pipe 5, an impurity absorption device drain pipe 6, an absorbent circulation device 7, a sedimentation alkali solution recovery device 8, a vacuum pump 9, a product gas holding tank 10, a main heat exchanger (optional) 11, a blower (optional) 12, a buffer tank 13, and a PSA separation and purification unit 14. Among them, the impurity absorption device 2 can also use other purification equipment, the cyclone separator 3 is an optional device, the structural form of the drying device 4 is optional, the product gas holding tank 10 is an optional device, and the main heat exchanger 11 and the blower 12 are both optional devices. The above optional devices can be replaced or cancelled under different working conditions, and the same recycling effect can be achieved.

[0029] The separation and purification subsystem is a PSA separation and purification device, which can effectively separate nitrogen, oxygen and carbon dioxide in the gas. The separation and purification subsystem of the present invention is mainly used to separate and purify the tail gas (the tail gas discharged by the carbonization tower), thereby increasing the concentration of carbon dioxide in the tail gas (from a concentration of about 12% to a concentration of 35%-65%), and other gases can be directly discharged. The compression subsystem 1 is arranged at the upstream end of the separation and purification subsystem, and can compress the gas, thereby providing kinetic energy for the gas to enter the separation and purification subsystem for separation.

[0030] In a specific embodiment of the present invention, the separation and purification subsystem includes a plurality of PSA separation and purification units 14. The present invention adopts the PSA separation and purification equipment in the prior art as the PSA separation and purification unit 14. The present invention does not make structural improvements to the PSA separation and purification unit, but applies the traditional PSA separation and purification equipment used to prepare nitrogen as a gas processing unit in the present invention to treat the tail gas so as to increase the concentration of carbon dioxide in the gas. This is a new application of the PSA separation and purification equipment. In the present invention, the specific structure of each PSA separation and purification unit 14 is not limited by the present invention, as long as it can process the gas and separate nitrogen and oxygen. In the present invention, a plurality of PSA separation and purification units 14 can be connected in series or in parallel.

[0031] The present invention processes the tail gas discharged from the carbonization tower, so the present invention also sets up an induced draft subsystem, which includes a blower 12, and the blower 12 is connected to the tail gas discharge port of the carbonization tower, and a buffer tank 13 is connected to the air outlet of the blower 12. The blower 12 provides kinetic energy to the tail gas, thereby inputting the tail gas into the buffer tank 13, and the buffer tank 13 temporarily stores the tail gas, that is, it can provide stable gas to the downstream, and can also process the gas in advance (for example, it can make the tail gas have a micro-pressure, and the impurities in the tail gas can be settled by standing still). The buffer tank 13 is connected to the pretreatment subsystem, and a buffer tank discharge port is set at the bottom of the buffer tank 13, which is used to discharge the impurities accumulated at the bottom of the inner side of the buffer tank 13 at any time.

[0032] It should be noted that the present invention is provided with a sewage pipeline and a sewage pool, and each device in the system that needs to discharge sewage can be connected to the sewage pipeline and then discharged into the sewage pool for centralized treatment.

[0033] In order to ensure the stable and safe operation of the separation and purification subsystem, the present invention also provides the following subsystem for pre-processing the separation and purification subsystem:

[0034] 1. Preprocessing subsystem.

[0035] The pretreatment subsystem is arranged at the upstream end of the separation and purification subsystem, and the pretreatment subsystem pretreats the tail gas discharged from the carbonization tower, and the pretreatment includes separation of particulate impurities, gas water washing and water separation.

[0036] Specifically, the pretreatment subsystem includes an impurity absorption device 2 (i.e., an absorption purification tower), which is used to wash the tail gas with water and remove water-soluble impurities in the tail gas by water washing; the pretreatment subsystem includes a cyclone separator 3, which is used to cyclone separate the particulate impurities and water droplets in the tail gas by cyclone separation; the pretreatment subsystem includes a drying device 4, which is used to dry the tail gas. Among them, the impurity absorption device 2, the cyclone separator 3 and the drying device 4 are connected in sequence. Further, the impurity absorption device 2 includes a vertically arranged tank structure, the top of the tank structure is used to discharge the treated gas, a spray pipe 5 is arranged inside the tank structure, a gas inlet is arranged on the side wall of the tank structure, the gas inlet is arranged near the lower end of the tank structure, the spray pipe 5 is arranged near the upper end of the tank structure, and the impurity absorption device sewage pipe 6 is arranged at the bottom of the tank structure. Furthermore, the pretreatment subsystem also includes an absorbent circulation device 7 and a deposited alkali solution recovery device 8 for treating the separated substances generated by the tail gas pretreatment; the impurity absorption equipment sewage pipe 6 is connected to the deposited alkali solution recovery device 8, and the absorbent circulation device 7 is connected to the deposited alkali solution recovery device 8 to provide power for alkali solution recovery. The cyclone separator 3 is connected to the drying device 4, and the compression subsystem 1 is arranged between the cyclone separator 3 and the drying device 4. In the present invention, the drying device 4 is a cold dryer, and of course other gas drying devices that can be used in industrial production are also used in the present invention.

[0037] The above-mentioned deposition alkali solution specifically refers to sodium carbonate, sodium bicarbonate or sodium sulfate deposition solution.

[0038] 2. Product gas holding tank 10.

[0039] The product gas holding tank 10 is arranged at the downstream end of the separation and purification subsystem, and is used for buffering and temporarily storing the product gas with high carbon dioxide concentration. Specifically, the separation and purification subsystem is connected with a vacuum pump 9, and the product gas holding tank 10 is connected through the vacuum pump 9.

[0040] 3. Other auxiliary subsystems.

[0041] Other auxiliary subsystems include heat exchange subsystem and control subsystem.

[0042] Specifically, the heat exchange subsystem includes a main heat exchanger 11, an exhaust gas heat exchange unit and a compressor heat exchange unit. The exhaust gas heat exchange unit is arranged on the exhaust gas discharge port of the carbonization tower, and is used to cool the high-temperature exhaust gas discharged from the carbonization tower and recover the exhaust gas heat energy. The compressor heat exchange unit is arranged at the exhaust port of the compressor, and is used to cool the high-temperature compressed gas output by the compressor and recover the compressed gas heat energy. The exhaust gas heat exchange unit and the compressor heat exchange unit are both connected to the main heat exchanger 11, and are used to transport the absorbed heat energy to the main heat exchanger 11; the main heat exchanger 11 is provided with a heat absorption pipeline, and the main heat exchanger 11 preheats the treated high carbon dioxide concentration gas and can return the heat absorption pipeline to the carbonization tower for reuse. The present invention uses a pipeline to transport the high-temperature exhaust gas. The exhaust gas heat exchange unit can be arranged on the outer surface of the pipeline, or it can be arranged inside the pipeline, so as to be able to exchange heat with the high-temperature exhaust gas. The heat exchange principle of the compressor heat exchange unit is the same as above, so as to be able to exchange heat with the compressed high-temperature exhaust gas. The exhaust gas heat exchange unit and the compressor heat exchange unit both use water as a heat energy carrier. After absorbing heat, the water is heated up and transported to the main heat exchanger 11, and then the gas (product gas) is preheated in the main heat exchanger 11. After releasing heat, the water is cooled down and transported to the exhaust gas heat exchange unit and the compressor heat exchange unit again to absorb heat.

[0043] Specifically, the control subsystem includes a controller and a solenoid valve. The controller is connected to each subsystem and the solenoid valve in the system. The solenoid valve is arranged on the connecting pipeline between the devices in each subsystem. The solenoid valve is arranged on the pipeline of the present invention (the pipeline for transporting gas). The controller is connected to the solenoid valve through a signal line, and each solenoid valve can be controlled to realize the conduction and cutoff of the pipeline.

[0044] From the above, it can be seen that the present invention provides a system for recovering and utilizing carbon dioxide in the tail gas of a baking soda carbonization tower process. In the present invention, the system includes: a separation and purification subsystem for PSA purification of the tail gas, through which the carbon dioxide in the tail gas discharged from the carbonization tower can be separated and purified, and a gas with a carbon dioxide concentration of 35%-65% (the concentration range is 35%-65% and can be used, and the optimal concentration is 40%-50%) is generated for reuse; a compression subsystem 1 for compressing the tail gas to provide kinetic energy for the separation and purification of the tail gas, the compression subsystem 1 is arranged at the process upstream of the separation and purification subsystem and is connected to the separation and purification subsystem.

[0045] In order to solve the many problems existing in the emission of high carbon dioxide content tail gas, the present invention provides a carbon dioxide recovery and utilization system in the tail gas of a baking soda carbonization tower process. Through the above structural design, the system provided by the present invention can perform multiple process operations such as induced draft-heat exchange-pretreatment-compression-purification on the discharged tail gas and then return it to the carbonization tower, so that the purified tail gas (with a higher carbon dioxide concentration in the gas, the concentration is close to 40%) can be used as raw gas. Through the overall design of the system, the present invention realizes the concentration, purification and reuse of tail gas. The present invention can reduce the addition of carbon dioxide gas, the raw material of the carbonization reaction, thereby saving the production capacity of the upstream calcined limestone, saving energy consumption, reducing tail gas emissions, and reducing environmental pollution and waste of resources.

[0046] The invention provides a system for recovering and utilizing carbon dioxide in tail gas from a baking soda carbonization tower process. In the system, the invention can purify, recover and recycle carbon dioxide in the tail gas after a baking soda carbonization reaction. The invention belongs to the technical field of industrial tail gas purification and separation and resource recycling.

[0047] The present invention provides a system for recovering and utilizing carbon dioxide in tail gas of a baking soda carbonization tower process. The system comprises six major parts: an induced draft subsystem, a heat exchange subsystem, a pretreatment subsystem, a compression subsystem 1, a separation and purification subsystem, and a control subsystem. Among them, the induced draft subsystem provides power for the tail gas of the carbonization tower, specifically including an induced draft fan, and the tail gas of the carbonization tower can be transported to the lower level (utilizing the system's process downstream equipment, namely the heat exchange subsystem) through the induced draft fan; the heat exchange subsystem is used to recover the heat energy in the tail gas and the waste heat of the compressor, and can preheat the purified carbon dioxide gas. The heat exchange subsystem consists of two parts: tail gas heat exchange and compressor heat exchange; the pretreatment subsystem provides a clean gas source for the lower-level separation and purification subsystem. In the present invention, the pretreatment subsystem includes an impurity absorption device 2 (used to absorb impurities in the tail gas, mainly water-soluble impurities), a cyclone separator 3 (which can perform cyclone separation on particulate impurities, water droplets, etc. in the tail gas), a drying device 4 (to dry the tail gas, so that the compressed gas becomes a dry gas), an absorbent circulation device 7, and a deposited alkali solution recovery device 8 (the absorbent circulation device 7 and the deposited alkali solution recovery device 8 are separated from the tail gas circulation loop The tail gas pretreatment equipment is used in conjunction with other components in the pretreatment subsystem, and is mainly used to process the separation substances produced by the tail gas pretreatment, such as the absorbent particles produced when the tail gas is recovered, the alkali solution generated by the tail gas washing, etc.); the compression subsystem 1 can pressurize the exhaust gas to 2-3 MPa. The compression subsystem 1 is composed of an industrial gas compressor to provide kinetic energy for gas separation; the separation and purification subsystem is the core of the entire tail gas recovery and treatment process, and is composed of an adsorption tower, an adsorbent, a buffer tank 13, a vacuum pump 9, etc., which can separate carbon dioxide and other gases such as nitrogen. The main component of the gas at the top of the tower is nitrogen, which can be returned to the chimney for direct discharge, and the bottom of the tower is discharged to obtain carbon dioxide with a concentration of about 35%-65%. This part of the gas is returned to the carbonization tower through a pipeline to mix with the raw gas inlet pipeline and then enters the carbonization tower to participate in the carbonization reaction; the control system includes control structures such as valve PLC and solenoid valves, which can control the start and close and operation of the recovery process.

[0048] The function of the heat exchange subsystem in the present invention is as follows: since the temperature of the exhaust gas discharged from the carbonization tower is between 90-110°C, and it needs to be cooled to below 40°C before entering the separation and purification subsystem, the heat exchange subsystem (exhaust gas heat exchange) is set in the present invention to cool the exhaust gas discharged from the carbonization tower, and at the same time, heat energy is recovered from the exhaust gas discharged from the carbonization tower, and the recovered heat energy can be used to preheat the purified gas; in addition, the compressor will generate heat when in operation, and the compressed gas will also heat up. The exhaust temperature of the compressed exhaust gas output by the compressor is between 110-120°C, and the high-temperature compression position output by the compressor needs to be further dried by a cold dryer. Therefore, the heat exchange subsystem (compressor heat exchange) is set in the present invention to recover heat energy from the compressed exhaust gas, and the recovered heat energy can be used to preheat the purified gas. By setting the heat exchange subsystem, the loss of heat energy of the carbonization tower reaction caused by emissions can be saved, thereby saving energy and reducing consumption.

[0049] The main functions of the present invention include: 1. Recycling the carbon dioxide from the exhaust gas; 2. Designing an alkali solution recovery system to reuse resources and reduce waste; 3. Designing a waste heat utilization system in the process to reduce energy consumption.

[0050] The purpose of the pretreatment subsystem of the present invention is as follows: the tail gas discharged from the carbonization tower contains impurities such as sodium carbonate, sodium bicarbonate, sulfide, nitrogen oxides, etc. If it directly enters the separation and purification subsystem without treatment, it will cause problems such as decreased adsorption separation efficiency or even failure, affecting the service life of the core adsorbent of the separation system and causing an increase in operation and maintenance costs.

[0051] It is known from common technical knowledge that the present invention can be implemented by other embodiments that do not deviate from its spirit or essential features. Therefore, the above disclosed embodiments are only illustrative in all respects and are not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are included in the present invention.

Claims

1. A system for recycling carbon dioxide in tail gas from a baking soda carbonization tower process, characterized in that: include: A separation and purification subsystem for PSA purification of tail gas, through which the carbon dioxide in the tail gas discharged from the carbonization tower can be separated and purified, and a gas with a carbon dioxide concentration of 35%-65% can be generated for reuse; A compression subsystem (1) is used for compressing tail gas to provide kinetic energy for separation and purification of the tail gas, wherein the compression subsystem is arranged upstream of the separation and purification subsystem and connected to the separation and purification subsystem.

2. The carbon dioxide recovery and utilization system in the process tail gas of the baking soda carbonization tower according to claim 1, characterized in that: The invention also comprises a pretreatment subsystem, which is used to pretreat the tail gas discharged from the carbonization tower, wherein the pretreatment includes separation of particulate matter, aerosol, impurities, gas water washing and water separation.

3. The carbon dioxide recovery and utilization system in the baking soda carbonization tower process tail gas according to claim 2, characterized in that: The pretreatment subsystem comprises an impurity absorption device (2) for washing the tail gas with water and removing water-soluble impurities in the tail gas by water washing; The pretreatment subsystem comprises a cyclone separator (3) for cyclone separation of particulate impurities and water droplets in the tail gas; The pretreatment subsystem comprises a drying device (4) for drying the tail gas; The impurity absorption device, the cyclone separator and the drying device are connected in sequence.

4. The carbon dioxide recovery and utilization system in the process tail gas of the baking soda carbonization tower according to claim 3 is characterized in that: The impurity absorption device comprises a vertically arranged tank structure, the top of the tank structure discharges purified gas and enters the downstream, a spray pipe (5) is arranged inside the tank structure, a gas inlet is arranged on the side wall of the tank structure, the gas inlet is arranged close to the lower end of the tank structure, the spray pipe is arranged close to the upper end of the tank structure, and an impurity absorption device sewage pipe (6) is arranged at the bottom end of the tank structure.

5. The carbon dioxide recovery and utilization system in the process tail gas of the baking soda carbonization tower according to claim 4 is characterized in that: The pretreatment subsystem also includes an absorbent circulation device (7) for treating the separated substances generated by the tail gas pretreatment and a sediment alkali solution recovery device (8); The impurity absorption equipment sewage pipe is connected to the sediment alkali solution recovery device, and the absorbent circulation device is connected to the sediment alkali solution recovery device to provide power for alkali solution recovery.

6. The carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process according to claim 5, characterized in that: The cyclone separator is connected to the drying device, and the compression subsystem is arranged between the cyclone separator and the drying device; The drying device is a cold dryer or a dryer.

7. The carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process according to claim 1 is characterized in that: A vacuum pump (9) is connected to the separation and purification subsystem, and a product gas holding tank (10) is connected via the vacuum pump.

8. The carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process according to claim 1 is characterized in that: The heat exchange subsystem includes a main heat exchanger (11), an exhaust gas heat exchange unit and a compressor heat exchange unit. The exhaust gas heat exchange unit is arranged at the exhaust gas discharge port of the carbonization tower and is used to cool the high-temperature exhaust gas discharged from the carbonization tower and recover the exhaust gas heat energy. The compressor heat exchange unit is arranged at the exhaust port of the compressor and is used to cool the high-temperature compressed gas output by the compressor and recover the compressed gas heat energy. The exhaust gas heat exchange unit and the compressor heat exchange unit are both connected to the main heat exchanger and are used to transport the absorbed heat energy to the main heat exchanger. The main heat exchanger is provided with a heat absorption pipeline, and the treated high carbon dioxide concentration gas is preheated by the main heat exchanger and can be returned to the carbonization tower through the heat absorption pipeline for reuse.

9. The carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process according to claim 1, characterized in that: The invention also comprises an induced draft subsystem, wherein the induced draft subsystem comprises a blower (12), wherein the blower is connected to the tail gas discharge port of the carbonization tower, and a buffer tank (13) is connected to the air outlet of the blower, wherein the buffer tank is connected to the pretreatment subsystem, and a buffer tank sewage outlet is arranged at the bottom of the buffer tank.

10. The carbon dioxide recovery and utilization system in the tail gas of the baking soda carbonization tower process according to claim 1 is characterized in that: It also includes a control subsystem, which includes a controller and a solenoid valve. The controller is controlled and connected with each subsystem and the solenoid valve in the system, and the solenoid valve is arranged on the connecting pipeline between the devices in each subsystem; The separation and purification subsystem includes a plurality of PSA separation and purification units (14).

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