A blast furnace gas carbon capture pretreatment system and adsorption desorption method

Abstract

The present application relates to the technical field of blast furnace gas treatment, and discloses an adsorption and desorption method of a blast furnace gas carbon capture pretreatment system, comprising a tower body, the bottom and top of which are respectively provided with a first opening and a second opening; a heat exchange pipeline is arranged in the tower body, the heat exchange pipeline is connected with a gas inlet of a pressure swing adsorption mechanism in the blast furnace gas carbon capture pretreatment system or the first opening of another tower body, a treatment cavity is formed between the heat exchange pipeline and the inner side wall of the tower body, the treatment cavity is filled with an adsorbent, and the treatment cavity is connected with the first opening and the second opening; a gas distributor is connected with the heat exchange pipeline; the first opening is also used for being connected with a first gas outlet of the pressure swing adsorption mechanism; the second opening is used for being connected with a gas inlet of the pressure swing adsorption mechanism; and the adsorbent in the treatment cavity comprises a saturated state and a desorption state. The present application can efficiently utilize the heat of blast furnace gas, prevent waste of heat energy, and improve energy utilization efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of blast furnace gas treatment, in particular to a blast furnace gas carbon capture pretreatment system and adsorption and desorption method. BACKGROUND

[0002] The CO2 in the steel industry mainly comes from the emission of the gas in the blast furnace process. For every ton of pig iron produced, 1300-1600 m 3 of blast furnace gas is generated. The blast furnace gas mainly contains N2 (40-60%), CO2 (15-30%), CO (20-30%), H2 (1-3%), CH4 (0.2-0.5%), and other combustible gases, and O2 (0.2-0.4%), H2O (6-8%), H2S / COS (100-200 ppm), and other impurity gases. In addition, it also contains a certain pressure and temperature. The capture of CO2 from blast furnace gas can reduce the CO2 emission of steel production.

[0003] For the reduction of CO2 in the blast furnace process, the adsorption capture method is a promising carbon reduction technology. According to the process requirements, the application of the adsorption method at present mainly includes the combination of temperature swing adsorption and pressure swing adsorption. This technology uses the selective adsorption of adsorbents for the adsorption performance difference of different gases. The temperature swing adsorption method is usually used for the pretreatment of blast furnace gas to remove the impurity gases in the gas and reduce the influence of impurity gases on carbon capture, so as to ensure the efficient capture of CO2 by the subsequent carbon capture device. Then, the pressure swing adsorption method is used for the capture of CO2 in blast furnace gas to obtain high-concentration CO2 gas. The temperature of blast furnace gas is generally above 100℃, which is not conducive to gas adsorption. The cooling treatment will cause waste of heat, resulting in the inability to utilize the heat. SUMMARY

[0004] The purpose of the present application is to provide a blast furnace gas carbon capture pretreatment system and adsorption and desorption method, which aims to solve or improve at least one of the above technical problems.

[0005] To achieve the above purpose, the present application provides the following scheme: the present application provides an adsorption and desorption method of a blast furnace gas carbon capture pretreatment system, which comprises:

[0006] The adsorption and desorption mechanism comprises:

[0007] The tower body is provided with a first opening and a second opening at the bottom and the top, respectively;

[0008] A heat exchange pipeline is arranged in the tower body, the heat exchange pipeline is connected with the gas inlet of the pressure swing adsorption mechanism in the blast furnace gas carbon capture pretreatment system or the first opening of another tower body, a treatment cavity is formed between the heat exchange pipeline and the inner wall of the tower body, the treatment cavity is filled with an adsorbent, and the treatment cavity is connected with the first opening and the second opening;

[0009] A gas distributor is connected with the heat exchange pipeline;

[0010] The first opening is also connected with the first gas outlet of the pressure swing adsorption mechanism;

[0011] The second opening is connected with the gas inlet of the pressure swing adsorption mechanism;

[0012] The adsorbent in the treatment cavity includes a saturated state and a desorbed state;

[0013] The use method of the adsorption and desorption mechanism includes:

[0014] When the adsorbent in the treatment cavity is in the saturated state, the gas distributor introduces blast furnace gas into the heat exchange pipeline, so that the blast furnace gas exchanges heat with the adsorbent through the pipe wall of the heat exchange pipeline to form low-temperature gas, and at the same time, the adsorbent enters the desorbed state, the low-temperature gas is introduced into the pressure swing adsorption mechanism for CO2 adsorption and capture, or the low-temperature gas is introduced into the first opening of another tower body in the desorbed state;

[0015] When the adsorbent in the treatment cavity is in the desorbed state, the low-temperature gas in the heat exchange pipeline of another tower body enters the treatment cavity through the first opening to purge the adsorbent, and then enters the pressure swing adsorption mechanism through the second opening to perform CO2 adsorption and capture, or the concentrated gas that is not adsorbed in the pressure swing adsorption mechanism is introduced into the treatment cavity through the first opening to purge the adsorbent, and then enters the pressure swing adsorption mechanism through the second opening to perform CO2 adsorption and capture.

[0016] Optionally, the gas distributor includes a plurality of external pipelines and a plurality of internal pipelines connected with each other, the plurality of external pipelines are used to connect the blast furnace gas, and the plurality of internal pipelines are connected with the heat exchange pipeline.

[0017] Optionally, the heat exchange pipeline is a plurality of spiral columns, and the plurality of spiral columns are connected with the plurality of internal pipelines.

[0018] Optionally, the plurality of spiral columns are connected with each other.

[0019] Optionally, the plurality of spiral columns are vertically arranged side by side.

[0020] Optionally, the blast furnace gas flow direction in the internal pipeline is perpendicular to the blast furnace gas flow direction in the spiral column pipe.

[0021] The application further provides a blast furnace gas carbon capture pretreatment system, comprising:

[0022] A gas source;

[0023] The adsorption and desorption method of the blast furnace gas carbon capture pretreatment system, the heat exchange pipeline is connected with the gas source, and the gas source is used for conveying the blast furnace gas to the heat exchange pipeline.

[0024] A pressure swing adsorption mechanism is used for CO2 capture of the blast furnace gas, and high-concentration CO2 gas is obtained after adsorption, and concentrated gas is not adsorbed, the pressure swing adsorption mechanism is provided with a gas inlet and a first gas outlet;

[0025] The gas inlet is connected with the heat exchange pipeline or the second opening, the first gas outlet is connected with the first opening, and the first gas outlet is used for conveying the concentrated gas to the first opening.

[0026] Optionally, the pressure swing adsorption mechanism is further provided with a second gas outlet, and the second gas outlet is used for discharging the high-concentration CO2 gas.

[0027] Optionally, the system further comprises a gas storage tank, and the gas storage tank is connected with the second opening.

[0028] Optionally, the adsorption and desorption mechanism is multiple.

[0029] The application discloses the following technical effects: the adsorbent after adsorption is arranged in the treatment cavity, then the blast furnace gas is introduced into the heat exchange pipeline through the gas distributor, the heat exchange between the heat exchange pipeline and the adsorbent can make the impurity gas adsorbed on the adsorbent desorbed by heat, the regeneration of the adsorbent is completed, and the blast furnace gas after temperature reduction forms low-temperature gas, the low-temperature gas is introduced into the treatment cavity of the tower body after the impurities in the adsorbent are removed, and then the low-temperature gas is introduced into the pressure swing adsorption mechanism for adsorption treatment or directly introduced into the pressure swing adsorption mechanism for adsorption treatment, the concentrated gas not adsorbed is introduced into the treatment cavity through the first opening to blow the adsorbent in the desorption state, the impurity gas desorbed from the adsorbent is discharged through the second opening, the regeneration of the adsorbent is realized, the blast furnace gas temperature can be effectively reduced, the adsorbent after adsorption can be desorbed and regenerated, the blast furnace gas heat can be efficiently utilized, the waste of heat energy is prevented, and the energy utilization efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] The accompanying drawings, which form a part of this application, are included to provide a further understanding of the application and are incorporated in and constitute a part of this application. The embodiments of the application illustrated in the drawings are provided to explain the present application and are not meant to limit the present application. In the drawings:

[0031] Fig. 1 A schematic diagram of the adsorption and desorption mechanism of the present application;

[0032] Fig. 2 A schematic diagram of the blast furnace gas carbon capture pretreatment system of the present application;

[0033] Fig. 3 A schematic diagram of the plurality of adsorption and desorption mechanisms of the present application.

[0034] In the figure: 1, tower body; 11, first opening; 12, second opening; 13, heat exchange pipeline; 14, treatment cavity; 15, gas distributor; 151, external pipeline; 152, internal pipeline; 2, pressure swing adsorption mechanism; 3, gas source; 4, high concentration CO2 gas. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0036] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0037] Reference Figs. 1-3 The present application provides an adsorption and desorption method of a blast furnace gas carbon capture pretreatment system, comprising:

[0038] The adsorption and desorption mechanism comprises:

[0039] The tower body 1 is provided with a first opening 11 and a second opening 12 at the bottom and the top, respectively;

[0040] The heat exchange pipeline 13 is arranged in the tower body 1, and the heat exchange pipeline 13 is connected in communication with the gas inlet of the pressure swing adsorption mechanism 2 in the blast furnace gas carbon capture pretreatment system or the first opening 11 of another tower body 1. The treatment cavity 14 is formed between the heat exchange pipeline 13 and the inner wall of the tower body 1, the treatment cavity 14 is filled with an adsorbent, and the treatment cavity 14 is connected in communication with the first opening 11 and the second opening 12;

[0041] The gas distributor 15 is connected in communication with the heat exchange pipeline 13;

[0042] The first opening 11 is also used to communicate with the first gas outlet of the pressure swing adsorption mechanism 2.

[0043] The second opening 12 is used to communicate with the inlet gas of the pressure swing adsorption mechanism 2.

[0044] The adsorbent in the processing cavity 14 includes a saturated state and a desorbed state.

[0045] The method for using the adsorption and desorption mechanism includes:

[0046] When the adsorbent in the processing cavity 14 is in the saturated state, the gas distributor 15 passes the blast furnace gas into the heat exchange pipeline 13 to make the blast furnace gas exchange heat between the tube wall of the heat exchange pipeline 13 and the adsorbent to form low-temperature gas, and at the same time, the adsorbent enters the desorbed state, the low-temperature gas is passed into the pressure swing adsorption mechanism 2 to adsorb and capture CO2, or the low-temperature gas is passed into the first opening 11 of another tower body 1 in the desorbed state.

[0047] When the adsorbent in the processing cavity 14 is in the desorbed state, the low-temperature gas in the heat exchange pipeline 13 in another tower body 1 is passed into the processing cavity 14 through the first opening 11 to purge the adsorbent, and then is passed into the pressure swing adsorption mechanism 2 through the second opening 12 to adsorb and capture CO2, or the concentrated gas that is not adsorbed in the pressure swing adsorption mechanism 2 is passed into the processing cavity 14 through the first opening 11 to purge the adsorbent, and then is passed into the pressure swing adsorption mechanism 2 through the second opening 12 to adsorb and capture CO2.

[0048] By arranging the adsorbent that has completed adsorption in the processing cavity 14, and then passing the blast furnace gas into the heat exchange pipeline 13 through the gas distributor 15, the impurity gas adsorbed on the adsorbent can be desorbed by heat exchange between the heat exchange pipeline 13 and the adsorbent to regenerate the adsorbent, and at the same time, the blast furnace gas is reduced in temperature to form low-temperature gas, which is passed into the processing cavity 14 of the tower body 1 that has completed desorption to remove impurities from the adsorbent, and then is passed into the pressure swing adsorption mechanism 2 to be adsorbed and treated, or is directly passed into the pressure swing adsorption mechanism 2 to be adsorbed and treated, the concentrated gas that is not adsorbed is passed into the processing cavity 14 through the first opening to purge the adsorbent that is in the desorbed state, and the impurity gas desorbed from the adsorbent is carried out through the second opening 12 to realize the regeneration of the adsorbent, which can not only effectively reduce the temperature of the blast furnace gas, but also make the adsorbent that has completed adsorption desorb and regenerate, and effectively utilize the heat of the blast furnace gas, prevent the waste of heat energy, and improve the energy utilization efficiency.

[0049] Further, the adsorbent is the adsorbent containing impurities after temperature swing adsorption.

[0050] Further optimization scheme, the gas distributor 15 comprises a plurality of external pipelines 151 and a plurality of internal pipelines 152, the plurality of external pipelines 151 are used for communicating the blast furnace gas, and the plurality of internal pipelines 152 are communicated with the heat exchange pipeline 13.

[0051] Further optimization scheme, the heat exchange pipeline 13 is a plurality of spiral columns, the plurality of spiral columns are communicated with the plurality of internal pipelines 152. The plurality of spiral columns are communicated. The plurality of spiral columns are vertically arranged side by side. The blast furnace gas in the internal pipeline 152 flows in a direction perpendicular to the blast furnace gas in the spiral column.

[0052] The plurality of external pipelines 151 and the plurality of internal pipelines 152 and the plurality of spiral columns are matched to realize multi-point distribution of the gas, heat the adsorbent at different positions, can realize uniform heating of the adsorbent, prevent uneven heating of the adsorbent in the conventional heat regeneration process, and local temperature is too high or too low, lead to the situation that the adsorbent is not completely regenerated, and effectively reduce the volume and floor area of the whole device.

[0053] The application also provides a blast furnace gas carbon capture pretreatment system, comprising:

[0054] The gas source 3;

[0055] An adsorption and desorption mechanism of a blast furnace gas carbon capture pretreatment system, the heat exchange pipeline 13 is communicated with the gas source 3, and the gas source 3 is used for conveying the blast furnace gas to the heat exchange pipeline 13;

[0056] The pressure swing adsorption mechanism 2 is used for capturing CO2 in the blast furnace gas, and high-concentration CO2 gas 4 is obtained after adsorption, and the non-adsorbed is concentrated gas. The pressure swing adsorption mechanism is provided with an air inlet and a first gas outlet;

[0057] The air inlet is communicated with the heat exchange pipeline 13 or the second opening 12, the first gas outlet is communicated with the first opening 11, and the first gas outlet is used for conveying the concentrated gas to the first opening 11.

[0058] Further optimization scheme, the pressure swing adsorption mechanism 2 is further provided with a second gas outlet, and the second gas outlet is used for discharging the high-concentration CO2 gas 4.

[0059] Further optimization scheme, further comprising a gas storage tank, and the gas storage tank is communicated with the second opening 12.

[0060] The gas storage tank can be used for storing the gas with impurities discharged from the second opening 12.

[0061] Further optimization scheme, the adsorption and desorption mechanism is a plurality of, and the plurality of adsorption and desorption mechanisms can be alternately operated, so that the blast furnace gas carbon capture pretreatment system maintains good working efficiency.

[0062] This embodiment is illustrated by taking steel blast furnace gas as the raw gas for CO2 capture. The composition of the raw gas is shown in Table 1.

[0063] Table 1

[0064]

[0065] The blast furnace gas is cooled to a temperature of 40°C, and then enters the pressure swing adsorption mechanism 2 for CO2 capture. Finally, high-concentration CO2 gas 4 is obtained.

[0066] The composition of the obtained high-concentration CO2 gas 4 is shown in Table 2.

[0067] Table 2

[0068]

[0069] Further, the composition of the blast furnace gas raw gas is the same, the blast furnace gas temperature is 120°C, and the blast furnace gas temperature after cooling is 60°C. The blast furnace gas enters the pressure swing adsorption mechanism 2 for CO2 capture, and finally high-concentration CO2 gas 4 is obtained.

[0070] The composition of the obtained high-concentration CO2 gas 4 is shown in Table 3.

[0071] Table 3

[0072]

[0073] Comparative Example 1

[0074] The composition of the blast furnace gas raw gas is the same, the blast furnace gas temperature is 120°C, and the blast furnace gas directly enters the pressure swing adsorption mechanism 2 for CO2 capture without cooling. Finally, high-concentration CO2 gas 4 is obtained.

[0075] The composition of the obtained high-concentration CO2 gas 4 is shown in Table 4.

[0076] Table 4

[0077]

[0078] In this comparative example, the blast furnace gas is not cooled, resulting in a too high temperature for pressure swing adsorption, and the CO2 adsorption effect is not good. The purity of the product gas of CO2 obtained is only 60.2%, indicating that it is necessary to cool the blast furnace gas.

[0079] In the description of the present application, it needs to be understood that the terms "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0080] The above-described embodiments are only to describe the preferred modes of the present application, and not to limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope determined by the claims of the present application.

Claims

1. An adsorption and desorption method for a blast furnace gas carbon capture and pretreatment system, characterized in that, include: The adsorption and desorption mechanism includes: The tower body (1) has a first opening (11) and a second opening (12) at its bottom and top, respectively. A heat exchange pipeline (13) is installed inside the tower body (1). The heat exchange pipeline (13) is connected to the air inlet of the pressure swing adsorption mechanism (2) in the blast furnace gas carbon capture pretreatment system or the first opening (11) of another tower body (1). A treatment cavity (14) is formed between the heat exchange pipeline (13) and the inner wall of the tower body (1). The treatment cavity (14) is filled with adsorbent. The treatment cavity (14) is connected to the first opening (11) and the second opening (12). Gas distributor (15) is connected to the heat exchange pipeline (13); The first opening (11) is also used to communicate with the first outlet of the pressure swing adsorption mechanism (2); The second opening (12) is used to connect with the inlet gas of the pressure swing adsorption mechanism (2); The adsorbent in the processing chamber (14) includes a saturated state and a desorption state; The method of using the adsorption and desorption mechanism includes: When the adsorbent in the processing chamber (14) is saturated, the gas distributor (15) introduces blast furnace gas into the heat exchange pipeline (13) so that the blast furnace gas exchanges heat with the adsorbent through the pipe wall of the heat exchange pipeline (13) to form low-temperature gas. At the same time, the adsorbent enters the desorption state. The low-temperature gas is introduced into the pressure swing adsorption mechanism (2) for CO2 adsorption and capture, or the low-temperature gas is introduced into the first opening (11) of another tower body (1) in the desorption state. When the adsorbent in the processing chamber (14) is in a desorption state, the low-temperature coal gas in the heat exchange pipeline (13) in another tower body (1) enters the processing chamber (14) through the first opening (11) to purge the adsorbent and then enters the pressure swing adsorption mechanism (2) through the second opening (12) to adsorb and capture CO2. Alternatively, the concentrated coal gas that has not been adsorbed in the pressure swing adsorption mechanism (2) is introduced into the processing chamber (14) through the first opening (11) to purge the adsorbent and then enters the pressure swing adsorption mechanism (2) through the second opening (12) to adsorb and capture CO2.

2. The adsorption and desorption method for a blast furnace gas carbon capture and pretreatment system according to claim 1, characterized in that: The gas distributor (15) includes multiple external pipes (151) and multiple internal pipes (152) connected to each other. The multiple external pipes (151) are used to connect to the blast furnace gas, and the multiple internal pipes (152) are connected to the heat exchange pipes (13).

3. The adsorption and desorption method for a blast furnace gas carbon capture and pretreatment system according to claim 2, characterized in that: The heat exchange pipeline (13) consists of multiple spiral tubes, which are connected to multiple internal pipelines (152).

4. The adsorption and desorption method for a blast furnace gas carbon capture and pretreatment system according to claim 3, characterized in that: Multiple spiral tubes are connected together.

5. The adsorption and desorption method for a blast furnace gas carbon capture and pretreatment system according to claim 3, characterized in that: Multiple spiral tubes are arranged vertically side by side.

6. The adsorption and desorption method for a blast furnace gas carbon capture and pretreatment system according to claim 3, characterized in that: The direction of blast furnace gas flow in the internal pipeline (152) is perpendicular to the direction of blast furnace gas flow in the spiral tube.

7. A blast furnace gas carbon capture and pretreatment system, characterized in that, include: Gas source (3); The adsorption and desorption method of the carbon capture pretreatment system for blast furnace gas according to any one of claims 1-6, wherein the heat exchange pipeline (13) is connected to the gas source (3), and the gas source (3) is used to supply the blast furnace gas to the heat exchange pipeline (13); Pressure swing adsorption mechanism (2) is used to capture CO2 in the blast furnace gas. After adsorption, high-concentration CO2 gas (4) is obtained, and the unadsorbed gas is concentrated gas. The pressure swing adsorption mechanism is provided with an inlet and a first outlet. The air inlet is connected to the heat exchange pipeline (13) or the second opening (12), and the first air outlet is connected to the first opening (11). The first air outlet is used to deliver the concentrated coal gas to the first opening (11).

8. A blast furnace gas carbon capture and pretreatment system according to claim 7, characterized in that: The pressure swing adsorption mechanism (2) is also provided with a second gas outlet, which is used to discharge the high concentration CO2 gas (4).

9. A blast furnace gas carbon capture and pretreatment system according to claim 7, characterized in that: It also includes a gas storage tank, which is connected to the second opening (12).

10. A blast furnace gas carbon capture and pretreatment system according to claim 7, characterized in that: The adsorption and desorption mechanism comprises multiple components.

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