Equipment for extracting CO2 from dry quenching circulating gas and dry quenching system
By introducing a gas-to-gas heat exchanger, a desulfurization adsorption tower, and a pressure swing adsorption tower into the dry quenching system, and utilizing the adsorbent to selectively adsorb CO2, the problem of high CO2 emissions in the circulating gas was solved, achieving efficient CO2 extraction and increased coke production.
Patent Information
- Application Number
- CN202423227380.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-26
AI Technical Summary
In existing dry quenching systems, the CO2 emissions from the circulating gas are high and not effectively utilized, leading to environmental pollution and reduced coke production.
The equipment system consists of a gas-to-gas heat exchanger, a desulfurization adsorption tower, a blower, and a pressure swing adsorption tower. It extracts CO2 through gas heat exchange, desulfurization, and pressure swing adsorption. It uses adsorbents to selectively adsorb CO2, separates high-concentration CO2, and reduces the CO2 and water vapor content in the circulating gas.
It significantly reduced CO2 emissions from the dry quenching system, decreased coke burn-off rate, increased coke production, and reduced CO2 and water vapor content in the circulating gas.
Smart Images
Figure CN223818422U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model provides a kind of equipment for extracting CO2 from dry quenching circulating gas and dry quenching system belongs to chemical industry field. BACKGROUND
[0002] Dry quenching system is the device for extinguishing coke in coking enterprise, which is used to reduce the red coke (1000℃) to below 200℃ by inert gas, and recover the waste heat of red coke. In the dry quenching process, the red coke is loaded from the top of the dry quenching furnace, the low-temperature inert gas is blown into the red coke layer in the dry quenching furnace cooling chamber by the circulating fan, absorbs the heat of the red coke, and the cooled coke is discharged from the bottom of the dry quenching furnace. The high-temperature inert gas from the dry quenching furnace annular flue is exchanged by the dry quenching boiler, the boiler generates steam, and the cooled inert gas is blown into the dry quenching furnace by the circulating fan for recycling.
[0003] To reduce the existence of combustible gas (H2 and CO) in the circulating gas, the dry quenching system introduces air at the dry quenching furnace annular flue to burn off the combustible gas components. In this way, the amount of circulating gas will gradually increase. To ensure the overall balance of the system circulating gas amount, a circulating gas emission pipe is generally installed on the pipeline after the economizer, which emits 5-15% of the total amount of circulating gas. This part of the emission gas emitted to the atmosphere contains 10-18% of CO2, which is also a problem of CO2 emission in the dry quenching process. CO2 is a greenhouse gas. If the CO2 in the dry quenching circulating gas is used as a resource and the CO2 with high purity is extracted as a product, not only the CO2 emission of the dry quenching system is reduced, but also the CO2 product can be obtained.
[0004] After extracting CO2 from the dry quenching circulating gas, the N2 content in the remaining gas increases, and the CO2 content and moisture content decrease significantly. The return to the lower air inlet of the dry quenching furnace can reduce the CO2 and water content in the circulating gas, thereby reducing the carbon melting reaction and water gas reaction in the dry quenching furnace, reducing the coke burning loss rate in the dry quenching furnace, and improving the coke yield. UTILITY MODEL CONTENTS
[0005] Technical problem: In order to solve the defects of the prior art, the utility model provides a kind of equipment for extracting CO2 from dry quenching circulating gas.
[0006] Technical scheme: The utility model provides a kind of equipment for extracting CO2 from dry quenching circulating gas, which comprises a gas-gas heat exchanger, a desulfurization adsorption tower, a blower, and a pressure swing adsorption tower. The desulfurization adsorption tower, the blower, and the pressure swing adsorption tower are connected in sequence. The hot medium pipeline outlet of the gas-gas heat exchanger is connected with the desulfurization adsorption tower, the cold medium pipeline inlet is connected with the cold medium outlet of the pressure swing adsorption tower, and the hot medium pipeline and the cold medium pipeline exchange heat in the gas-gas heat exchanger.
[0007] As an improvement, a dust collector is also included, which is connected to the heat medium pipeline inlet of the gas-to-gas heat exchanger.
[0008] As another improvement, a regulating valve is also included, which is connected to the refrigerant pipe outlet of the gas-to-gas heat exchanger.
[0009] As another improvement, the pressure swing adsorption tower is divided into a high-pressure section and a low-pressure section; the high-pressure section is filled with adsorbent and connected to a blower, and a CO2 pipe is installed on the high-pressure section; the gas outlet of the low-pressure section is a residual gas pipe, which is connected to the refrigerant pipeline inlet of the gas-to-gas heat exchanger.
[0010] This utility model also provides a dry quenching coke system, including a dry quenching furnace, a dry quenching boiler, a blower, and an economizer connected in a ring in sequence. A circulating gas vent pipe is provided on the pipeline between the economizer and the dry quenching furnace. The system also includes a gas-to-gas heat exchanger, a desulfurization adsorption tower, a blower, and a pressure swing adsorption tower, which are connected in sequence. The inlet of the heat medium pipeline of the gas-to-gas heat exchanger is connected to the pipeline between the economizer and the circulating gas vent pipe, and the outlet of the heat medium pipeline is connected to the desulfurization adsorption tower. The inlet of the cold medium pipeline of the gas-to-gas heat exchanger is connected to the cold medium outlet of the pressure swing adsorption tower, and the outlet of the cold medium pipeline is connected to the pipeline between the circulating gas vent pipe and the dry quenching furnace. The heat medium pipeline and the cold medium pipeline exchange heat in the gas-to-gas heat exchanger.
[0011] As an improvement, a dust collector is also included, which is connected to the heat medium pipeline inlet of the gas-to-gas heat exchanger.
[0012] As another improvement, a regulating valve is also included, which is connected to the refrigerant pipe outlet of the gas-to-gas heat exchanger.
[0013] As another improvement, the pressure swing adsorption tower is divided into a high-pressure section and a low-pressure section; the high-pressure section is filled with adsorbent and connected to a blower, and a CO2 pipe is installed on the high-pressure section; the gas outlet of the low-pressure section is a residual gas pipe, which is connected to the refrigerant pipeline inlet of the gas-to-gas heat exchanger.
[0014] Beneficial effects: The equipment and process of this invention can significantly reduce the CO2 and water vapor content in the original circulating gas of dry quenching coke, reduce the carbon melting reaction and water-gas reaction in the high-temperature zone of the dry quenching furnace, and reduce the coke burn-off rate by 0.3%-0.7%. This increases coke production. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of a device for extracting CO2 from the circulating gas in a dry quenching coke cycle. Detailed Implementation
[0016] The present invention will be further described below.
[0017] The dry quenching system includes a dry quenching furnace 7, a dry quenching boiler 8, a blower 9, and an economizer 10 connected in a ring. A circulating gas vent pipe 11 is provided on the pipeline between the economizer 10 and the dry quenching furnace 7. The system also includes a dust collector 1, a gas-to-gas heat exchanger 2, a desulfurization adsorption tower 3, a blower 4, a pressure swing adsorption tower 5, and a regulating valve 6. The desulfurization adsorption tower 3, the blower 4, and the pressure swing adsorption tower 5 are connected in sequence. The dust collector 1 is connected to the pipeline between the economizer 10 and the circulating gas vent pipe 11. The inlet of the heat medium pipeline of the gas-to-gas heat exchanger 2 is connected to the dust collector 1, and the outlet of the heat medium pipeline is connected to the desulfurization adsorption tower 3. The inlet of the cold medium pipeline of the gas-to-gas heat exchanger 2 is connected to the cold medium outlet of the pressure swing adsorption tower 5, and the outlet of the cold medium pipeline is connected to the regulating valve 6. The regulating valve 6 is connected to the pipeline between the circulating gas vent pipe 11 and the dry quenching furnace 7. The heat medium pipeline and the cold medium pipeline exchange heat in the gas-to-gas heat exchanger 2. The pressure swing adsorption tower 5 is divided into a high-pressure section and a low-pressure section; the high-pressure section is filled with adsorbent and connected to the blower 4, and a CO2 pipe 51 is installed on the high-pressure section; the gas outlet of the low-pressure section is a residual gas pipe 52, which is connected to the refrigerant pipeline inlet of the gas-to-gas heat exchanger 2.
[0018] During operation, a portion of the circulating gas exiting the economizer 10 enters the heat medium pipeline of the gas-to-gas heat exchanger 2, where it exchanges heat with the gas in the coolant pipeline before entering the desulfurization adsorption tower 3 for desulfurization. The desulfurized gas is then pressurized by the blower 4 and enters the pressure swing adsorption tower 5, where CO2 is adsorbed by the adsorbent. The remaining gas enters the coolant pipeline of the gas-to-gas heat exchanger 2, where it exchanges heat with the gas in the heat medium pipeline before entering the dry quenching furnace 7. The CO2 adsorbed in the pressure swing adsorption tower 5 is then removed and separated to obtain a high concentration of CO2. 2， The process is as follows: The main components of the circulating gas are N2~80%, CO2~15%, CO~5%, and H2~1%. A pressure swing adsorption (PSA) tower 5 is filled with an adsorbent (such as a molecular sieve) with strong selective adsorption capacity for CO2. The outlet of PSA tower 5 is controlled by an electrically controlled valve according to a program. The high-pressure stage and the low-pressure stage are connected to either the CO2 pipe 51 or the residual gas pipe 52, respectively. In the high-pressure stage, i.e., the adsorption stage, the adsorbent selectively absorbs CO2, and the CO2 concentration in the outlet gas of PSA tower 5 decreases significantly, while other gas components are hardly absorbed by the adsorbent. The outlet gas flows through the residual gas pipe 52. In the low-pressure stage, i.e., the desorption stage, CO2 is desorbed from the adsorbent. During this stage, the CO2 concentration in the outlet gas of PSA tower 5 is very high, generally reaching over 90%. The output gas in this desorption stage is the CO2 extracted from the dry quenching circulating gas, and the outlet gas flows through the CO2 pipe 51.
[0019] The following provides a more detailed explanation of how the system works.
[0020] A portion of circulating gas is drawn from the economizer's circulating gas pipeline of the existing dry quenching system. This portion of gas has a temperature of 120-140℃ and a pressure of 3-6 kPa, containing 10-18% CO2. After dust removal by dust collector 1, it passes through gas-to-gas heat exchanger 2, where it exchanges heat with the low-temperature gas after CO2 removal, lowering the temperature to 30-50℃ before entering desulfurization adsorption tower 3. In desulfurization adsorption tower 3, the gas comes into full contact with the desulfurization adsorbent, and SO2 in the circulating gas is adsorbed and removed. The desulfurized gas is then blown through a blower... The gas is pressurized by the machine 4 and enters the pressure swing adsorption tower 5. In the pressure swing adsorption tower 5, CO2 is adsorbed and removed by the adsorbent, separating two gas streams: high-concentration CO2 (CO2 pipe 51) and residual gas (residual gas pipe 52). The high-concentration CO2 is output as product CO2, and the CO2 content in the residual gas is reduced to below 5%. After passing through the gas-to-gas heat exchanger 2, the residual gas is sent back to the dry quenching furnace circulating gas inlet pipe of the original dry quenching system through the regulating valve 6. After mixing with other circulating gases, it enters the dry quenching furnace to cool the coke.
[0021] Because the concentrations of CO2 and water vapor in the gas after CO2 removal are very low, the concentrations of CO2 and water vapor in the mixed circulating gas are reduced, thereby reducing the overall CO2 emissions of the dry quenching system. For a typical 140-ton / hour dry quenching unit, this can reduce CO2 emissions by 15,000 to 25,000 tons per year. This new process reduces the CO2 and water vapor content in the original circulating gas of the dry quenching furnace, which in turn reduces the carbon melting reaction and water-gas reaction in the high-temperature zone, lowering the coke burn-off rate by 0.3% to 0.7% and increasing coke production.
[0022] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.
Claims
1. A device for extracting CO2 from dry quenching circulating gas, characterized in that: The system includes a gas-to-gas heat exchanger (2), a desulfurization adsorption tower (3), a blower (4), and a pressure swing adsorption tower (5), which are connected in sequence. The outlet of the heat medium pipeline of the gas-to-gas heat exchanger (2) is connected to the desulfurization adsorption tower (3), and the inlet of the cold medium pipeline is connected to the cold medium outlet of the pressure swing adsorption tower (5). The heat medium pipeline and the cold medium pipeline exchange heat in the gas-to-gas heat exchanger (2).
2. The apparatus for extracting CO2 from dry quenching circulating gas according to claim 1, characterized in that: It also includes a dust collector (1), which is connected to the heat medium pipeline inlet of the gas-to-gas heat exchanger (2).
3. The apparatus for extracting CO2 from dry quenching circulating gas according to claim 1, characterized in that: It also includes a regulating valve (6), which is connected to the refrigerant pipeline outlet of the gas-to-gas heat exchanger (2).
4. The apparatus for extracting CO2 from dry quenching circulating gas according to claim 1, characterized in that: The pressure swing adsorption tower (5) is divided into a high-pressure section and a low-pressure section; the high-pressure section is filled with adsorbent and connected to a blower (4); a CO2 pipe (51) is installed on the high-pressure section; the gas outlet of the low-pressure section is a residual gas pipe (52), which is connected to the refrigerant pipe inlet of the gas-to-gas heat exchanger (2).
5. A dry quenching coke system, comprising a dry quenching furnace (7), a dry quenching boiler (8), a blower (9), and an economizer (10) connected in a ring in sequence, wherein a circulating gas venting pipe (11) is provided on the pipeline between the economizer (10) and the dry quenching furnace (7), characterized in that: It also includes a gas-to-gas heat exchanger (2), a desulfurization adsorption tower (3), a blower (4), and a pressure swing adsorption tower (5), which are connected in sequence; the inlet of the heat medium pipeline of the gas-to-gas heat exchanger (2) is connected to the pipeline between the economizer (10) and the circulating gas vent pipe (11), and the outlet of the heat medium pipeline is connected to the desulfurization adsorption tower (3); the inlet of the cold medium pipeline of the gas-to-gas heat exchanger (2) is connected to the cold medium outlet of the pressure swing adsorption tower (5), and the outlet of the cold medium pipeline is connected to the pipeline between the circulating gas vent pipe (11) and the dry quenching furnace (7); the heat medium pipeline and the cold medium pipeline exchange heat in the gas-to-gas heat exchanger (2).
6. A dry quenching system according to claim 5, characterized in that: It also includes a dust collector (1), which is connected to the heat medium pipeline inlet of the gas-to-gas heat exchanger (2).
7. A dry quenching system according to claim 5, characterized in that: It also includes a regulating valve (6), which is connected to the refrigerant pipeline outlet of the gas-to-gas heat exchanger (2).
8. A dry quenching system according to claim 5, characterized in that: The pressure swing adsorption tower (5) is divided into a high-pressure section and a low-pressure section; the high-pressure section is filled with adsorbent and connected to a blower (4); a CO2 pipe (51) is installed on the high-pressure section; the gas outlet of the low-pressure section is a residual gas pipe (52), which is connected to the refrigerant pipe inlet of the gas-to-gas heat exchanger (2).