Industrial flue gas carbon dioxide capture conversion method and application

Abstract

This application provides a method and application for capturing and converting carbon dioxide in industrial flue gas, relating to the field of carbon dioxide capture technology. The method includes the following steps: industrial flue gas is fed into the upper part of a cyclone separator, causing the flue gas flow to rotate downwards along the cylinder wall in the upper part of the cyclone separator; simultaneously, fresh air is fed into the lower part of the cyclone separator, causing the air flow to rotate downwards along the cylinder wall in the lower part of the cyclone separator; and the cyclone separator is cooled, allowing the industrial flue gas and air to react under conditions of temperature below 10°C and pressure not less than 0.12 MPa to generate a mixed acid containing carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas. The entire process is simple and rapid, effectively capturing carbon dioxide from industrial flue gas, with low cost, high safety and practical value, and can also be applied to flue gas purification and compound fertilizer preparation.

Description

Technical Field

[0001] This application relates to the field of carbon dioxide capture technology, and more specifically, to a method and application for capturing and converting carbon dioxide in industrial flue gas. Background Technology

[0002] Currently, common industrial methods for capturing carbon dioxide include chemical adsorption, physical adsorption, high-pressure liquefaction, and molecular sieve technology. For example, publication number CN114602294A discloses a two-phase absorbent for capturing CO2, which captures carbon dioxide through chemical adsorption; another example is authorization publication number CN214222307U, which discloses an integrated system for enriching and liquefying carbon dioxide in industrial waste gas, using high-pressure liquefaction to capture and store carbon dioxide.

[0003] In actual production, the adsorption process is complex, has poor stability and safety, and high-pressure liquefaction is prone to safety accidents such as leakage. It is also costly and difficult to promote and apply on a large scale in industry. Summary of the Invention

[0004] The purpose of this application is to provide a method for capturing and converting carbon dioxide in industrial flue gas. The entire process is simple and fast, and it can effectively capture carbon dioxide in industrial flue gas. It is low in cost, safe, and has high practical value.

[0005] Another objective of this application is to provide an application of an industrial flue gas carbon dioxide capture and conversion method in industrial flue gas purification.

[0006] Another objective of this application is to provide an application of an industrial flue gas carbon dioxide capture and conversion method in the preparation of compound fertilizer from industrial flue gas.

[0007] The technical problem solved by this application is achieved by the following technical solution.

[0008] In a first aspect, embodiments of this application provide a method for capturing and converting carbon dioxide in industrial flue gas, comprising the following steps: sending industrial flue gas into the upper part of a cyclone separator to cause the flue gas flow to rotate downward along the cylinder wall in the upper part of the cyclone separator; simultaneously sending fresh air into the lower part of the cyclone separator to cause the air flow to rotate downward along the cylinder wall in the lower part of the cyclone separator; and cooling the cyclone separator to allow the industrial flue gas and air to react under conditions of temperature less than 10°C and pressure not less than 0.12 MPa to generate a mixed acid including carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas.

[0009] Secondly, embodiments of this application provide an application of an industrial flue gas carbon dioxide capture and conversion method in industrial flue gas purification and treatment.

[0010] Thirdly, embodiments of this application provide an application of an industrial flue gas carbon dioxide capture and conversion method in the preparation of compound fertilizer from industrial flue gas.

[0011] Compared with the prior art, the embodiments of this application have at least the following advantages or beneficial effects:

[0012] Regarding the first aspect, embodiments of this application provide a method for capturing and converting carbon dioxide in industrial flue gas. Industrial flue gas is fed into the upper cylindrical part of a cyclone separator using a blower, nozzle, or other equipment. The industrial flue gas is pressurized and injected into the interior of the cyclone separator, causing the flue gas to form an airflow that rotates rapidly downwards along the side wall of the cyclone separator. Similarly, fresh air from the outside is fed into the lower conical part of the cyclone separator using an air compressor, nozzle, or other equipment. The fresh air is pressurized and injected into the interior of the cyclone separator, also causing the fresh air to form an airflow that rotates rapidly downwards along the side wall of the cyclone separator. During this process, the rotational speed of the airflow is greater than that of the flue gas flow. Under the action of the pressure difference, the flue gas flow at the upper part is dragged and accelerated downwards. Simultaneously, the cyclone separator is cooled, ultimately forming a wall-mounted "super-gravity centrifugal freezing pressure field" inside the cyclone separator, with a temperature less than 10°C and a pressure not less than 0.12 MPa. Under these conditions, moisture in the industrial flue gas condenses into droplets. The carbon monoxide and carbon dioxide in the flue gas, under the pressure and temperature provided by the "hypergravity centrifugal freezing pressure field," alter the chemical reaction pressure equilibrium parameters that would normally prevent a reaction, allowing the three to react rapidly to produce carbonic acid. Similarly, toxic substances in the industrial flue gas, such as nitric oxide, nitrogen dioxide, and sulfur dioxide, can also react to form corresponding acids. The relevant reactions are as follows:

[0013] 2CO + 2CO₂ + 4H₂O + O₂ → 4H₂CO₃

[0014] CO2 + H2O → H2CO3

[0015] 4NO + 2H₂O + 3O₂ → 4HNO₃

[0016] 4NO2 + 2H2O + O2 → 4HNO3

[0017] 2SO2 + 2H2O + O2 → 2H2SO4

[0018] The entire method is simple and can effectively capture carbon dioxide in industrial flue gas, while also purifying it. It is low-cost, economical, and environmentally friendly, with a safe and stable process and high practical value.

[0019] Regarding the second aspect, embodiments of this application provide an application of an industrial flue gas carbon dioxide capture and conversion method in industrial flue gas purification, which can repeatedly process industrial flue gas through multiple stages to achieve different capture and purification effects.

[0020] Regarding the third aspect, the application provides an application of an industrial flue gas carbon dioxide capture and conversion method in the preparation of compound fertilizer from industrial flue gas. During the treatment of industrial flue gas using this method, liquid nitrogen or ammonia can be appropriately introduced into the cyclone separator. Under the conditions provided by the "hypergravity centrifugal freezing pressure field," it can react with the obtained carbonic acid to generate ammonium bicarbonate compound fertilizer containing small amounts of ammonium nitrate and ammonium sulfate. After simple dehydration treatment, an agricultural compound fertilizer with an ammonium bicarbonate content of over 97% can be obtained. The relevant reactions are as follows:

[0021] H₂CO₃ + NH₃ → NH₄HCO₃

[0022] H₂SO₄ + 2NH₃ → (NH₄)₂SO₄

[0023] HNO3 + NH3 → NH4NO3 Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and therefore should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of the apparatus for realizing the industrial flue gas carbon dioxide capture and conversion method provided in this application.

[0026] Icons: 1. Shell; 11. Sealing baffle; 2. Cyclone tube; 21. Columnar tube; 22. Conical tube; 23. Cooling chamber; 3. First chamber; 4. Second chamber; 5. First airflow nozzle; 6. Second airflow nozzle; 7. Feeding pipe; 8. Collection pipe; 81. Exhaust pipe; 9. Collection box; 100. Circulating cooling device; 101. Inlet; 102. Outlet; 200. Medium and high pressure blower; 300. Air compressor. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0029] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0030] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0031] In the description of the embodiments of this application, it should be noted that if terms such as "upper," "lower," "inner," or "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0032] In the description of the embodiments of this application, "a plurality of" means at least two.

[0033] In the description of the embodiments of this application, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0034] Where there is no conflict, the embodiments and features described in this application can be combined with each other. The application will now be described in detail with reference to specific embodiments.

[0035] This application provides a method for capturing and converting carbon dioxide in industrial flue gas, comprising the following steps: sending industrial flue gas into the upper part of a cyclone separator to cause the flue gas flow to rotate downward along the cylinder wall in the upper part of the cyclone separator; simultaneously sending fresh air into the lower part of the cyclone separator to cause the air flow to rotate downward along the cylinder wall in the lower part of the cyclone separator; and cooling the cyclone separator to allow the industrial flue gas and air to react under conditions of temperature less than 10°C and pressure not less than 0.12 MPa to generate a mixed acid containing carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas.

[0036] In the above embodiments, industrial flue gas is fed into the upper cylindrical part of the cyclone separator using a blower, nozzle, or other equipment, and the industrial flue gas is pressurized and injected into the interior of the cyclone separator, causing the industrial flue gas to form an airflow that rotates downward at high speed along the side wall of the cyclone separator. Similarly, fresh air from the outside is fed into the lower conical part of the cyclone separator using an air compressor, nozzle, or other equipment, and the fresh air is pressurized and injected into the interior of the cyclone separator, also causing the fresh air to form an airflow that rotates downward at high speed along the side wall of the cyclone separator. During this process, the rotational speed of the airflow is greater than that of the flue gas flow. Under the action of the pressure difference, the flue gas flow at the top is dragged and accelerated downward to rotate. At the same time, the cyclone separator is cooled, and a wall-oriented "super-gravity centrifugal freezing pressure field" is finally formed inside the cyclone separator, with a temperature of less than 10°C and a pressure of not less than 0.12 MPa. Under these conditions, the moisture in the industrial flue gas condenses into droplets. The carbon monoxide and carbon dioxide in the flue gas react with the fresh air under the pressure and temperature provided by the "hypergravity centrifugal freezing pressure field," changing the chemical reaction pressure balance parameters that are not easily reacted under normal conditions, allowing the three to react rapidly to produce carbonic acid. Similarly, toxic substances such as nitric oxide, nitrogen dioxide, and sulfur dioxide contained in the industrial flue gas can also react to form corresponding acids.

[0037] The entire method is simple and can effectively capture carbon dioxide in industrial flue gas, while also purifying it. It is low-cost, economical, and environmentally friendly, with a safe and stable process and high practical value.

[0038] Furthermore, in some embodiments of this application, industrial flue gas is sent into the upper part of the cyclone separator by a medium- and high-pressure blower at a pressure of 4500 to 7500 Pa; and fresh air is sent into the lower part of the cyclone separator by an air compressor at a pressure of 0.6 to 0.8 MPa.

[0039] Furthermore, in some embodiments of this application, the tangential velocity of the flue gas flow during rotation is 14–40 m / s; the tangential velocity of the air flow during rotation is 60–150 m / s.

[0040] Furthermore, in some embodiments of this application, the cyclone is cooled by a cooling medium with a temperature of 5°C to -15°C.

[0041] In the above embodiments, by controlling conditions such as pressure, airflow velocity, and cooling temperature, a wall-oriented "super-gravity centrifugal freezing pressure field" can be formed inside the cyclone, which is more conducive to the reaction, improves the effect of carbon dioxide capture and conversion, and is more beneficial to industrial production.

[0042] Furthermore, in some embodiments of this application, it is implemented by the following device: including a housing 1, a cyclone 2 is disposed inside the housing 1, the bottom of the cyclone 2 is connected to the bottom of the housing 1; a cavity is formed between the cyclone 2 and the housing 1, a sealing baffle 11 is disposed in the cavity, the sealing baffle 11 is sleeved on the cyclone 2 and connected to the inner wall of the housing 1, the sealing baffle 11 divides the cavity into a first chamber 3 and a second chamber 4, the first chamber 3 is located above the second chamber 4; a cooling chamber 23 is disposed on the side wall of the cyclone 2, and a first spray assembly and a second spray assembly are also disposed on the side wall of the cyclone 2, the first spray assembly is located in the first chamber 3, and the second spray assembly is located in the second chamber 4.

[0043] In the above embodiments, during actual use, industrial flue gas is sent into the first chamber 3 inside the housing 1 via a blower or other equipment, and the flue gas is injected at high speed into the cyclone 2 via the first injection assembly, causing the flue gas to rotate downwards along the inner wall of the cyclone 2. During this process, the cooling chamber 23 is filled with a cooling medium, which can cool the rotating flue gas; at the same time, fresh air is sent into the second chamber 4, and the fresh air is injected at high speed into the lower part of the cyclone 2 via the second injection assembly, causing the fresh air to also rotate along the inner wall of the cyclone 2; at this time, the upper part of the conical cylinder is a high-speed downward rotating flue gas flow, and the lower part is a high-speed downward rotating air flow. Under the pressure difference generated by the high-speed air flow in the upper part, the high-speed air flow in the lower part will cause the upper flue gas to rotate downwards around the inner wall of the cyclone 2 more quickly. At the same time, under the action of the cooling medium in the cooling chamber 23, a wall-oriented "super-gravity centrifugal freezing pressure field" will eventually be formed inside the cyclone 2. Under these conditions, moisture in the industrial flue gas condenses into droplets. The carbon monoxide and carbon dioxide in the flue gas, under the pressure and temperature provided by the "hypergravity centrifugal freezing pressure field," alter the chemical reaction pressure balance parameters that would normally prevent a reaction, allowing the three to react rapidly to produce carbonic acid. Similarly, toxic substances such as nitric oxide, nitrogen dioxide, and sulfur dioxide in the industrial flue gas can also react to form corresponding acids. If liquid nitrogen or ammonia is appropriately introduced into the cyclone 2, under the conditions provided by the "hypergravity centrifugal freezing pressure field," it can react with the obtained carbonic acid to produce ammonium bicarbonate compound fertilizer containing small amounts of ammonium nitrate and ammonium sulfate. Simple dehydration treatment then yields an agricultural compound fertilizer with an ammonium bicarbonate content of over 97%.

[0044] The entire equipment has a simple structure and can purify flue gas while capturing carbon dioxide. It can also further convert the captured carbon dioxide into compound nitrogen fertilizer, realizing resource recycling and reuse. The entire process is safe, stable, simple, fast, highly stable, and low-cost. It features energy saving, emission reduction, economic and environmental protection, and resource conservation, making it highly practical.

[0045] Furthermore, in some embodiments of this application, the first injection assembly includes a plurality of first airflow nozzles 5, the second injection assembly includes a plurality of second airflow nozzles 6, the first airflow nozzles 5 and the second airflow nozzles 6 are both disposed through the side wall of the cyclone 2, the air inlet ends of the first airflow nozzles 5 and the second airflow nozzles 6 are both located in the cavity, and the air outlet ends are both located inside the cyclone 2 and are positioned lower than the air inlet ends.

[0046] In the above embodiment, the multiple first airflow nozzles 5 and multiple second airflow nozzles 6, which are inclined downwards toward the inside of the cyclone 2, can better achieve high-speed downward rotation of the airflow along the inner wall of the cyclone 2, resulting in better performance. The airflow velocity of the second nozzles is greater than that of the first airflow nozzles 5, so as to accelerate and drag the upward flue gas flow through the pressure difference.

[0047] Furthermore, in some embodiments of this application, the cyclone 2 includes a cylindrical tube 21 and a conical tube 22. The end of the conical tube 22 with a larger diameter is connected to the end of the cylindrical tube 21, and the end of the conical tube 22 with a smaller diameter is connected to the bottom of the housing 1 and communicates with the outside. The sealing baffle 11 is located between the cylindrical tube 21 and the conical tube 22. The cylindrical tube 21 is located in the first chamber 3, and the conical tube 22 is located in the second chamber 4.

[0048] In the above embodiments, this configuration makes the device structure more reasonable and helps to enhance the capture effect.

[0049] Furthermore, in some embodiments of this application, the above-mentioned device further includes a circulating cooling device 100, which is provided with an outlet 102 and an inlet 101. The outlet 102 is connected to the bottom of the cooling chamber 23 through a pipe, and the inlet 101 is connected to the top of the cooling chamber 23 through a pipe.

[0050] In the above embodiments, liquid nitrogen or ammonia can be added while fresh air is introduced into the second chamber 4 through the feeding pipe 7, so as to react the captured carbon dioxide into ammonium bicarbonate compound fertilizer and realize the reuse of resources.

[0051] This application also provides an application of an industrial flue gas carbon dioxide capture and conversion method in industrial flue gas purification.

[0052] This application also provides an application of an industrial flue gas carbon dioxide capture and conversion method in the preparation of compound fertilizer from industrial flue gas.

[0053] The features and performance of this application will be further described in detail below with reference to the embodiments.

[0054] Example 1

[0055] This embodiment provides a method for capturing and converting carbon dioxide in industrial flue gas, comprising the following steps: Industrial flue gas is fed into the upper part of a cyclone separator at a pressure of 4500 Pa using a medium-high pressure blower, causing the flue gas flow to rotate downwards along the cyclone wall at a tangential velocity of 14 m / s. Simultaneously, fresh air is fed into the lower part of the cyclone separator at a pressure of 0.6 MPa using an air compressor, causing the air flow to rotate downwards along the cyclone wall at a tangential velocity of 60 m / s. The cyclone separator is then cooled using a cooling medium at a temperature of 5°C, allowing the industrial flue gas and air to react under conditions of less than 10°C and a pressure not less than 0.12 MPa to generate a mixed acid containing carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas.

[0056] Example 2

[0057] This embodiment provides a method for capturing and converting carbon dioxide in industrial flue gas, comprising the following steps: Industrial flue gas is fed into the upper part of a cyclone separator at a pressure of 7500 Pa using a medium-high pressure blower, causing the flue gas flow to rotate downwards along the cyclone wall at a tangential velocity of 40 m / s. Simultaneously, fresh air is fed into the lower part of the cyclone separator at a pressure of 0.8 MPa using an air compressor, causing the air flow to rotate downwards along the cyclone wall at a tangential velocity of 150 m / s. The cyclone separator is then cooled using a cooling medium at a temperature of -15°C, allowing the industrial flue gas and air to react under conditions of less than 10°C and a pressure not less than 0.12 MPa to generate a mixed acid containing carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas.

[0058] Example 3

[0059] This embodiment provides a method for capturing and converting carbon dioxide in industrial flue gas, comprising the following steps: Industrial flue gas is fed into the upper part of a cyclone separator at a pressure of 6000 Pa using a medium-high pressure blower, causing the flue gas flow to rotate downwards along the cyclone wall at a tangential velocity of 30 m / s. Simultaneously, fresh air is fed into the lower part of the cyclone separator at a pressure of 0.8 MPa using an air compressor, causing the air flow to rotate downwards along the cyclone wall at a tangential velocity of 120 m / s. The cyclone separator is then cooled using a cooling medium at a temperature of -10°C, allowing the industrial flue gas and air to react under conditions of less than 10°C and a pressure not less than 0.12 MPa to generate a mixed acid containing carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas.

[0060] Example 4

[0061] Please refer to Figure 1 This embodiment provides a method for capturing and converting carbon dioxide in industrial flue gas, which is implemented through the following apparatus:

[0062] The device includes a housing 1, within which a cyclone 2 is disposed, the bottom of which is connected to the bottom of the housing 1; a cavity is formed between the cyclone 2 and the housing 1, and a sealing baffle 11 is disposed within the cavity, the sealing baffle 11 being sleeved on the cyclone 2 and connected to the inner wall of the housing 1, the sealing baffle 11 dividing the cavity into a first chamber 3 and a second chamber 4, the first chamber 3 being located above the second chamber 4; a cooling chamber 23 is disposed on the side wall of the cyclone 2, and a first spray assembly and a second spray assembly are also disposed on the side wall of the cyclone 2, the first spray assembly being located in the first chamber 3 and the second spray assembly being located in the second chamber 4.

[0063] The first injection assembly includes a plurality of first airflow nozzles 5, and the second injection assembly includes a plurality of second airflow nozzles 6. The first airflow nozzles 5 and the second airflow nozzles 6 are both disposed on the side wall of the cyclone 2. The air inlet ends of the first airflow nozzles 5 and the second airflow nozzles 6 are both located in the cavity, and the air outlet ends are both located inside the cyclone 2 and are positioned lower than the air inlet ends.

[0064] The aforementioned cyclone 2 includes a cylindrical tube 21 and a conical tube 22. The larger diameter end of the conical tube 22 is connected to the end of the cylindrical tube 21, and the smaller diameter end of the conical tube 22 is connected to the bottom of the housing 1 and communicates with the outside. The aforementioned sealing baffle 11 is located between the cylindrical tube 21 and the conical tube 22. The cylindrical tube 21 is located in the first chamber 3, and the conical tube 22 is located in the second chamber 4.

[0065] It also includes a circulating cooling device 100, which is provided with an outlet 102 and an inlet 101. The outlet 102 is connected to the bottom of the cooling chamber 23 through a pipe, and the inlet 101 is connected to the top of the cooling chamber 23 through a pipe.

[0066] The specific method is as follows: Industrial flue gas is introduced into the first chamber 3 at a pressure of 6000 Pa by a medium-high pressure blower 200, and then injected into the cyclone separator 2 through the first airflow nozzle 5 to form a flue gas flow. The flue gas then rotates downwards along the wall of the cyclone separator 2 at a tangential velocity of 30 m / s. Simultaneously, fresh air is introduced into the second chamber 4 at a pressure of 0.8 MPa by an air compressor 300, and then injected into the cyclone separator 2 through the second airflow nozzle 6 to form an airflow. 2. The lower part rotates downward along the cylinder wall at a tangential speed of 120 m / s; at the same time, the cooling medium at a temperature of -10℃ is introduced into the cooling chamber 23 through the outlet 102 by the above-mentioned circulating cooling device 100 to cool the cyclone cylinder 2, and the circulating medium in the cooling chamber 23 is recovered through the inlet 101; finally, the industrial flue gas reacts with air under the conditions of temperature less than 10℃ and pressure not less than 0.12 MPa to generate mixed acid including carbonic acid, which captures and converts carbon dioxide in the industrial flue gas.

[0067] Test case

[0068] The flue gas generated from tire burning was treated using an industrial flue gas carbon dioxide capture and conversion method provided in Example 4 of this application. Detailed state data changes before and after flue gas treatment were detected and recorded. Specific items and results are shown in Table 1.

[0069] Table 1

[0070]

[0071]

[0072] The results show that, by using the industrial flue gas carbon dioxide capture and conversion method provided in this application to treat tire combustion flue gas, the total amount of exhaust gas is reduced by 53.6%, water vapor is condensed into liquid water and recovered at 89.7%, CO2 is converted into H2CO3 at a rate as high as 66.5%, and SO2 is reduced by 53.6%. X 99.8% of H2SO4 was converted to NO. X It was converted to HNO3 at 81.2%, with a significant effect.

[0073] In summary, the embodiments of this application provide a method and application for capturing and converting carbon dioxide in industrial flue gas. This method uses a blower, nozzle, or other equipment to deliver industrial flue gas into the upper cylindrical part of a cyclone separator, pressurizing and injecting the flue gas into the interior of the cyclone separator, causing the flue gas to form an airflow that rotates downwards at high speed along the side wall of the cyclone separator. Similarly, an air compressor, nozzle, or other equipment is used to deliver fresh air from the outside into the lower conical part of the cyclone separator, pressurizing and injecting the fresh air into the interior of the cyclone separator, also causing the fresh air to form an airflow that rotates downwards at high speed along the side wall of the cyclone separator. During this process, the rotational speed of the airflow is greater than that of the flue gas flow. Under the action of the pressure difference, the flue gas flow at the upper part is dragged and accelerated downwards. Simultaneously, the cyclone separator is cooled, ultimately forming a wall-mounted "super-gravity centrifugal freezing pressure field" inside the cyclone separator, with a temperature less than 10°C and a pressure not less than 0.12 MPa. Under these conditions, moisture in the industrial flue gas condenses into droplets. The carbon monoxide and carbon dioxide in the flue gas react with those in the fresh air under the pressure and temperature provided by the "hypergravity centrifugal freezing pressure field," altering the chemical reaction pressure balance parameters that would normally prevent a reaction. This allows the three substances to react rapidly to produce carbonic acid. Similarly, toxic substances such as nitric oxide, nitrogen dioxide, and sulfur dioxide in the industrial flue gas can also react to form corresponding acids. The entire method is simple, effectively capturing and purifying carbon dioxide from industrial flue gas. It is low-cost, economical, and environmentally friendly, with a safe and stable process, high practical value, and can also be applied to industrial flue gas purification and the conversion of waste into compound fertilizers.

[0074] The above are merely preferred embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for capturing and converting carbon dioxide in industrial flue gas, characterized in that, It includes the following steps: industrial flue gas is sent into the upper part of the cyclone separator so that the flue gas flow rotates downward along the cylinder wall in the upper part of the cyclone separator; at the same time, fresh air is sent into the lower part of the cyclone separator so that the air flow rotates downward along the cylinder wall in the lower part of the cyclone separator; and the cyclone separator is cooled so that the industrial flue gas and air react under the conditions of temperature less than 10°C and pressure not less than 0.12MPa to generate mixed acid including carbonic acid, thereby capturing and converting carbon dioxide in the industrial flue gas. The method is implemented by the following device: a housing, in which a cyclone cylinder is disposed, the bottom of the cyclone cylinder being connected to the bottom of the housing; a cavity is formed between the cyclone cylinder and the housing, a sealing baffle is disposed within the cavity, the sealing baffle is sleeved on the cyclone cylinder and connected to the inner wall of the housing, the sealing baffle dividing the cavity into a first chamber and a second chamber, the first chamber being located above the second chamber; a cooling chamber is disposed on the side wall of the cyclone cylinder, and a first spray assembly and a second spray assembly are also disposed on the side wall of the cyclone cylinder, the first spray assembly being located in the first chamber and the second spray assembly being located in the second chamber.

2. The industrial flue gas carbon dioxide capture and conversion method according to claim 1, characterized in that, Industrial flue gas is fed into the upper part of the cyclone separator by a medium- and high-pressure blower at a pressure of 4500–7500 Pa; fresh air is fed into the lower part of the cyclone separator by an air compressor at a pressure of 0.6–0.8 MPa.

3. The industrial flue gas carbon dioxide capture and conversion method according to claim 1, characterized in that, The tangential velocity of the flue gas flow during rotation is 14–40 m / s; the tangential velocity of the air flow during rotation is 60–150 m / s.

4. The industrial flue gas carbon dioxide capture and conversion method according to claim 1, characterized in that, The cyclone is cooled by a cooling medium with a temperature of 5℃ to -15℃.

5. The industrial flue gas carbon dioxide capture and conversion method according to claim 1, characterized in that, The first injection assembly includes a plurality of first airflow nozzles, and the second injection assembly includes a plurality of second airflow nozzles. Both the first airflow nozzles and the second airflow nozzles are disposed through the side wall of the cyclone. The air inlet ends of both the first airflow nozzles and the second airflow nozzles are located inside the cavity, and the air outlet ends are located inside the cyclone and are positioned lower than the air inlet ends.

6. The industrial flue gas carbon dioxide capture and conversion method according to claim 1, characterized in that, The cyclone includes a cylindrical tube and a conical tube. The end of the conical tube with a larger diameter is connected to the end of the cylindrical tube, and the end of the conical tube with a smaller diameter is connected to the bottom of the shell and communicates with the outside. The sealing baffle is located between the cylindrical tube and the conical tube. The cylindrical tube is located in the first chamber, and the conical tube is located in the second chamber.

7. The industrial flue gas carbon dioxide capture and conversion method according to claim 1, characterized in that, The device also includes a circulating cooling device, which has an outlet and an inlet. The outlet is connected to the bottom of the cooling chamber via a pipe, and the inlet is connected to the top of the cooling chamber via a pipe.

8. The application of the industrial flue gas carbon dioxide capture and conversion method as described in any one of claims 1-7 in the purification and treatment of industrial flue gas.

9. The application of the industrial flue gas carbon dioxide capture and conversion method as described in any one of claims 1-7 in the preparation of compound fertilizer from industrial flue gas.

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