Non-disturbance furnace changing and pressure exhaust gas recycling device for hot blast stove

Abstract

The utility model provides an undisturbed furnace changing and pressure exhaust gas recycling device for hot-blast stoves, which comprises a plurality of hot-blast stoves, a plurality of groups of gas storage tanks and an air compressor, and blast furnaces, chimneys and air blowers are respectively arranged on the peripheral sides of the hot-blast stoves; the blast furnace, the chimney and the air blower are connected with all the hot-blast stoves through hot-air pipelines, smoke pipelines and cold-air pipelines; a combustion-supporting air header pipe is further arranged on one side of the cold air pipeline, and the air storage tanks are connected in series and connected with all the hot blast stoves through first pipelines. A second pipeline is connected with the cold air header pipe; a third pipeline is connected with the combustion-supporting air header pipe; the air compressor is connected with the multiple sets of air storage tanks through a fourth pipeline and used for inflating the air storage tanks. The blast furnace blower does not need to shunt air quantity and pressure in the hot-blast stove changing and pressurizing process, and waste gas released in the hot-blast stove air supply to combustion process can be recycled.

Description

Technical Field

[0001] The utility model relates to the technical field of hot blast stove supporting equipment for ironmaking blast furnaces, in particular to a hot blast stove non-disturbance furnace replacement and exhaust gas recovery device. Background Art

[0002] Hot blast furnaces are key components of the blast furnace ironmaking process. Their primary function is to continuously supply high-temperature hot air to the blast furnace. To ensure a stable supply of hot air, blast furnaces are typically equipped with three or four hot blast furnaces, alternating between combustion and heat storage and heating and blasting. When a hot blast furnace, after a period of air supply, fails to maintain the required air temperature, it must be replaced with another hot blast furnace operating on combustion and heat storage. The original hot blast furnace, meanwhile, switches to combustion and heat storage. Therefore, each hot blast furnace has three operating phases: combustion and heat storage, furnace stalling, and heat exchange and air supply. During a hot blast furnace (BF) heat-up / heat-down transition, the pressure inside the furnace approaches zero, leading to a significant pressure differential between the inside and outside. The hot blast furnace's air supply to the blast furnace must equalize the pressure within the furnace. Therefore, the furnace must be pressurized before air is delivered. The air volume required for the traditional hot blast furnace pressurization process comes from the cold air duct, which normally supplies air. During this period, the flow rate and pressure inside the blast furnace experience a step-like decrease. This reduces the actual air flow during the hot blast furnace change, causing fluctuations in furnace temperature and pressure. This is the reason for the pressure fluctuations during the hot blast furnace change. If the blast furnace does not operate smoothly, it can lead to further instability and even accidents. Therefore, to minimize fluctuations in air pressure and air volume, the hot blast furnace typically sends a signal to the blast furnace and energy management departments at the time of the change to obtain permission.

[0003] The main technical requirements for hot blast furnace replacement are: (1) small pressure fluctuation, fast speed, and no air leakage; (2) wind pressure fluctuation: less than 20kPa for large blast furnaces and less than 10kPa for small blast furnaces; (3) wind temperature fluctuation: wind temperature fluctuation is not more than 50℃.

[0004] In order to eliminate the fluctuation of blast furnace air supply pressure and flow during hot blast furnace replacement, the current mainstream mode of handling fluctuations in blast furnace hot blast furnace replacement in the ironmaking industry is to use cold air pressurization or fan constant pressure blasting. However, these methods have lags in the regulation of air pressure and air volume, and the air temperature, air pressure and flow entering the furnace fluctuate greatly, which will still affect the smooth operation and stability of the blast furnace. Utility Model Content

[0005] In order to solve the deficiencies in the prior art, the utility model provides a hot blast stove non-disturbance furnace changing and exhaust gas recovery device, which does not require the blast furnace blower to divert air volume and pressure during the hot blast stove furnace changing and pressurizing process, and can recover the exhaust gas released during the hot blast stove air supply to combustion process.

[0006] In order to achieve the above purpose, the specific solution adopted by the utility model is:

[0007] A device for undisturbed hot blast stove replacement and exhaust gas recovery, comprising several hot blast stoves, one of which is in a pressurized state, another in a exhaust state, and the remaining hot blast stoves in an air supply state; blast furnaces, chimneys, and blowers are respectively provided on the periphery of the hot blast stoves; the blast furnace is connected to all the hot blast stoves via a hot blast duct, the chimneys are connected to all the hot blast stoves via a flue gas duct, and the blowers are connected to all the hot blast stoves via a cold air duct; wherein the flue gas duct comprises a flue gas main pipe and several flue gas branch pipes, the flue gas main pipe is connected to the corresponding hot blast stoves via corresponding flue gas branch pipes; the cold air duct comprises a cold air main pipe and several cold air branch pipes, the cold air main pipe is connected to the corresponding hot blast stoves via corresponding cold air branch pipes; a combustion air main pipe is further provided on one side of the cold air main pipe; and further comprising:

[0008] Several groups of gas storage tanks are arranged in series and used as external gas sources. The gas storage tanks are connected to all hot blast furnaces through a first pipeline to provide exhaust gas recovery and pressurization functions for the hot blast furnaces; they are connected to the cold air main pipe through a second pipeline to supply cold air to the gas storage tanks; and they are connected to the combustion air main pipe through a third pipeline to supply oxygen-rich gas to the combustion air main pipe.

[0009] The air compressor is connected to a plurality of gas storage tanks through a fourth pipeline and is used for filling the gas storage tanks with air.

[0010] Furthermore, the first pipeline includes a first main pipe connecting a plurality of gas storage tanks, and a plurality of first branch pipes connected to the first main pipe at one end and to the flue gas branch pipe at the other end, and a shut-off valve is provided on the first main pipe and each first branch pipe;

[0011] The second pipeline includes a plurality of second branch pipes, one end of which is connected to the corresponding group of gas storage tanks and the other end is connected to the cold air main pipe, and each second branch pipe is provided with a stop valve and a pressure regulating valve;

[0012] The third pipeline includes a third main pipe connected to the combustion air main pipe, and a plurality of third branch pipes connected to the third main pipe at one end and connected to the corresponding group of gas storage tanks at the other end. Each third branch pipe is equipped with a stop valve, a pressure regulating valve and a check valve.

[0013] The fourth pipeline includes a fourth main pipe connected to the air compressor, and a plurality of fourth branch pipes, one end of which is connected to the fourth main pipe and the other end of which is connected to the corresponding group of air storage tanks.

[0014] Furthermore, a fifth pipeline is provided between any group of gas storage tanks and all hot blast furnaces, which can simultaneously deliver cold air and gas in the gas storage tanks to the hot blast furnaces.

[0015] Furthermore, the fifth pipeline includes a fifth main pipe connected to the gas storage tank, and a fifth branch pipe connected to the fifth main pipe at one end and connected to the corresponding cold air branch pipe at the other end. The fifth main pipe is provided with a shut-off valve, a pressure-stabilizing valve and a check valve, and each fifth branch pipe is provided with a shut-off valve.

[0016] Furthermore, each group of gas storage tanks includes two gas storage tanks, one of which is connected to the first pipeline and the second pipeline, and the other is connected to the third pipeline and the fourth pipeline.

[0017] Furthermore, a stop valve is provided between two adjacent groups of gas storage tanks.

[0018] Beneficial effects:

[0019] The utility model discloses a disturbance-free furnace exchange and pressure-exhaust gas recovery device for hot blast furnaces, comprising a plurality of hot blast furnaces, a plurality of gas storage tanks and air compressors, wherein one of the hot blast furnaces is used for pressurization (for the convenience of description, it is referred to as a pressurized hot blast furnace, and the pressurized hot blast furnace is a furnace that is about to perform combustion and heat storage), another hot blast furnace is used for pressure relief (for the convenience of description, it is referred to as a pressure relief hot blast furnace, and the pressure relief hot blast furnace is a furnace that switches from air supply to combustion), and the remaining hot blast furnaces are used for air supply (for the convenience of description, it is referred to as an air supply hot blast furnace, and the air supply hot blast furnace is a furnace that is performing heating and blasting). The pressurized hot blast furnace is pressurized by means of gas storage tanks and pressure relief hot blast furnaces, wherein the pressure relief hot blast furnace is charged with waste gas generated during combustion, and the high-pressure cold air in the furnace is heated by combustion and heat storage to form high-temperature and high-pressure hot air above 1200°C, which is sent into the blast furnace for smelting. During the firing and air supply cycle of multiple hot blast furnaces, high-pressure gas from the exhaust hot blast furnaces and air compressors is received through gas storage tanks, providing exhaust gas recovery and pressurization functions for the hot blast furnaces, and the two functions do not interfere with each other. During the hot blast furnace replacement and pressurization process, there is no need for the blast furnace blower to divert air volume and pressure. In addition, the exhaust gas released by the exhaust hot blast furnace can be recovered and used to re-pressurize the pressurized hot blast furnace. This completely eliminates the fluctuation of air supply pressure during the hot blast furnace replacement and recovers the hot blast furnace exhaust pressure, achieving the combined effect of stable pressure and reduced losses during the furnace replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the non-disturbance furnace replacement and exhaust gas recovery device for the hot blast furnace of the present invention.

[0021] Graphic markings: 1. First air storage tank, 2. Second air storage tank, 3. First stop valve, 4. Second stop valve, 5. Third air storage tank, 6. Fourth air storage tank, 7. Third stop valve, 8. Fourth pipeline, 9. Air compressor, 10. Fourth stop valve, 11. First pipeline, 12. Third pipeline, 13. Fifth stop valve, 14. First pressure-stabilizing valve, 15. Sixth stop valve, 16. Second pressure-stabilizing valve, 17. First check valve, 18. Seventh stop valve, 19. Second pressure-stabilizing valve, 20. Second check valve, 21. Eighth stop valve, 22. Third pressure-stabilizing valve, 23. Third check valve, 24. Ninth stop valve, 25. Fourth pressure-stabilizing valve, 26. Tenth stop valve, 27. Second pipeline, 28. Fifth pipeline, 29. Combustion air main , 30. Cold air main pipe, 31. Eleventh stop valve, 32. Twelfth stop valve, 33. Thirteenth stop valve, 34. Fourteenth stop valve, 35. Fifteenth stop valve, 36. Sixteenth stop valve, 37. Seventeenth stop valve, 38. Eighteenth stop valve, 39. Nineteenth stop valve, 40. Twentieth stop valve, 41. Twenty-first stop valve, 42. Twenty-second stop valve, 43. Twenty-third stop valve, 44. Twenty-fourth stop valve, 45. Twenty-fifth stop valve, 46. Twenty-sixth stop valve, 47. Chimney, 48. First air supply hot blast furnace, 49. Second air supply hot blast furnace, 50. Exhaust pressure hot blast furnace, 51. Pressurized hot blast furnace, 52. Blast furnace, 53. Flue gas branch pipe, 54. Cold air branch pipe, 55. Hot air duct DETAILED DESCRIPTION

[0022] The following will clearly and completely describe the technical solutions of the present invention in conjunction with specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0023] In the description of the present invention, it should be understood that the terms "upper" and "lower" etc. indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present invention.

[0024] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0025] The utility model provides a device for hot blast furnace non-disturbance furnace replacement and exhaust gas recovery, which includes several hot blast furnaces, air compressors and several groups of gas storage tanks. Figure 1 The specific structure of the utility model is elaborated in detail.

[0026] <Hot air furnace>

[0027] There are four hot blast furnaces, one of which is in a pressurized state and is about to perform combustion and heat storage. This furnace is called a pressurized hot blast furnace 51. Another hot blast furnace is in a depressurized state and is a furnace that switches from air supply to combustion. This furnace is called a depressurized hot blast furnace 50. The remaining two hot blast furnaces are in an air supply state, that is, furnaces that are currently supplying air. These two furnaces are called a first air supply hot blast furnace 48 and a second air supply hot blast furnace 49.

[0028] The four hot blast stoves have identical pipes around them, ensuring their functions can be switched according to actual circumstances. Specifically, the blast furnace 52 is connected to all the hot blast stoves via a hot blast duct 55, the chimney 47 is connected to all the hot blast stoves via a flue gas duct, and the blower (not shown) is connected to all the hot blast stoves via a cold air duct. The hot blast duct 55 includes a hot blast main pipe and hot blast branch pipes connecting each hot blast stove. The flue gas duct includes a flue gas main pipe and several flue gas branch pipes 53, which are connected to the hot blast stoves via the flue gas branch pipes 53. The cold air duct includes a cold air main pipe 30 and several cold air branch pipes 54, which are connected to the hot blast stoves via the cold air branch pipes 54. A combustion air main pipe 29 is also located on one side of the cold air main pipe 30.

[0029] Among them, each hot blast furnace is connected to two flue gas branch pipes, one of which is connected to both the chimney 47 and the first pipeline 11, and the other is only connected to the chimney 47 (this branch pipe is provided with a 20th stop valve 40 (corresponding to the charging and exhaust valve 51), a 22nd stop valve 42 (corresponding to the pressure-discharging hot blast furnace 50), a 24th stop valve 44 (corresponding to the second air supply hot blast furnace 49), and a 26th stop valve 46 (corresponding to the first air supply hot blast furnace 48)). Each cold air branch pipe 54 is provided with a stop valve. The stop valves related to the present invention introduced here are the 19th stop valve 39 (corresponding to the charging and exhaust valve 51), the 21st stop valve 41 (corresponding to the pressure-discharging hot blast furnace 50), the 23rd stop valve 43 (corresponding to the second air supply hot blast furnace 49), and the 25th stop valve 45 (corresponding to the first air supply hot blast furnace 48).

[0030] Specifically, the gas charged into the pressurized hot blast furnace 51 mainly comes from two aspects: on the one hand, the gas from the gas storage tank, and on the other hand, the exhaust gas from the pressure-discharging hot blast furnace 50 .

[0031] <Gas Tank>

[0032] Two sets of gas tanks are provided, serving as an external gas source for the pressurized hot blast furnace 51. These two sets are connected in series. The first set includes a first gas tank 1 and a second gas tank 2, while the second set includes a third gas tank 5 and a fourth gas tank 6. A second shut-off valve 4 is provided in the pipeline between the second and third gas tanks 2 and 5.

[0033] Taking the first gas storage tank 1 as an example, the gas filled into the first gas storage tank 1 mainly comes from the following aspects: (1) air compressor 9, which will be described in detail in the air compressor section below; (2) cold air main pipe 30, which is used to fill cold air into the first gas storage tank 1; (3) exhaust hot air furnace 50, which is used to fill exhaust gas into the first gas storage tank 1. It can be seen that the gas source of the gas storage tank is very wide and can provide sufficient gas source for each hot air furnace.

[0034] <Air compressor 9>

[0035] The air compressor 9 is connected to the air storage tank via a fourth pipeline 8 for filling the air storage tank. Specifically, the air compressor 9 is connected to the second air storage tank 2 in the first group of air storage tanks and the fourth air storage tank 6 in the second group of air storage tanks.

[0036] <First Pipeline 11>

[0037] The gas storage tank is connected to all the hot blast stoves through the first pipeline 11, providing waste gas recovery and pressurization functions for the hot blast stoves.

[0038] The first pipeline 11 includes a first main pipe connected at one end to the first gas storage tank 1 and at the other end to the fourth gas storage tank 6, and a plurality of first branch pipes connected at one end to the first main pipe and at the other end to corresponding hot blast furnaces. The first main pipe is equipped with two shut-off valves: a tenth shut-off valve 26 located adjacent to the first gas storage tank 1 and a fourth shut-off valve 10 located adjacent to the fourth gas storage tank 6. Each first branch pipe is equipped with a shut-off valve. The first branch pipe connected to the pressurized hot blast furnace 51 is equipped with an eighteenth shut-off valve 38, the first branch pipe connected to the pressure relief hot blast furnace 50 is equipped with a sixteenth shut-off valve 36, the first branch pipe connected to the second air supply hot blast furnace 49 is equipped with a fourteenth shut-off valve 34, and the first branch pipe connected to the first air supply hot blast furnace 48 is equipped with a twelfth shut-off valve 32.

[0039] <Second Pipeline 27>

[0040] The two groups of gas tanks are connected to the cold air main 30 via a second pipeline 27, which delivers cold air to the tanks. Second pipeline 27 comprises two second branch pipes, one end of which is connected to the corresponding group of gas tanks and the other end is connected to the cold air main 30. Each second branch pipe is equipped with a shutoff valve and a pressure-stabilizing valve. The second branch pipe connected to the first group of gas tanks is equipped with a ninth shutoff valve 24 and a fifth pressure-stabilizing valve 25. The second branch pipe connected to the second group of gas tanks is equipped with a fifth shutoff valve 13 and a first pressure-stabilizing valve 14.

[0041] <Third pipeline 12>

[0042] The two groups of gas storage tanks are connected to the combustion air main pipe 29 via a third pipeline 12, which delivers oxygen-enriched gas to the combustion air main pipe 29. The third pipeline 12 includes a third main pipe connected to the combustion air main pipe and two third branch pipes, one end of which is connected to the third main pipe and the other end is connected to the corresponding group of gas storage tanks. Each third branch pipe is equipped with a shutoff valve, a pressure-stabilizing valve, and a check valve. The third branch pipe connected to the first group of gas storage tanks is equipped with a seventh shutoff valve 18, a third pressure-stabilizing valve 19, and a second check valve 20. The third branch pipe connected to the second group of gas storage tanks is equipped with a sixth shutoff valve 15, a second pressure-stabilizing valve 16, and a first check valve 17.

[0043] <Fourth Pipeline 8>

[0044] The air compressor 9 is connected to the two groups of gas storage tanks through a fourth pipeline 8, wherein the fourth pipeline 8 includes a fourth main pipe connected to the air compressor 9 at one end, and two fourth branch pipes connected to the fourth main pipe at one end and the other end to the corresponding group of gas storage tanks. Each fourth branch pipe is provided with a stop valve, namely the first stop valve 3 (corresponding to the first group of gas storage tanks) and the third stop valve 7 (corresponding to the second group of gas storage tanks).

[0045] <Fifth Pipeline 28>

[0046] A fifth pipeline 28 is also installed between the first set of gas storage tanks and all hot blast furnaces, enabling the simultaneous delivery of cold air and gas from the gas storage tanks to the hot blast furnaces. Specifically, fifth pipeline 28 comprises a fifth main pipe connected to the first set of gas storage tanks and four fifth branch pipes, each connected to the fifth main pipe at one end and to corresponding cold air branch pipes 54 at the other end.

[0047] Among them, the fifth main pipe is provided with an eighth stop valve 21, a fourth pressure-stabilizing valve 22 and a third check valve 23, and each fifth branch pipe is provided with a stop valve, namely the seventeenth stop valve 37 (corresponding to the pressurized hot air furnace 51), the fifteenth stop valve 35 (corresponding to the pressure-discharging hot air furnace 50), the thirteenth stop valve 13 (corresponding to the second air supply hot air furnace 49) and the eleventh stop valve 31 (corresponding to the first air supply hot air furnace 48).

[0048] It should be noted that the device has multiple modes for exhaust gas recovery and disturbance-free furnace replacement. Figure 1 The use of the device is described in detail. Before use, all valves are in the closed state as an example.

[0049] In the case of exhaust gas recovery mode A, it operates as follows:

[0050] (1) Open the tenth stop valve 26 and the eighteenth stop valve 38, and the gas in the first group of gas storage tanks enters the pressurized hot air furnace 51. After the pressure is balanced, close the tenth stop valve 26, and the first group of gas storage tanks is in a low pressure state;

[0051] (2) Open the sixteenth stop valve 36, and the high-pressure gas in the pressure-discharging hot blast furnace 50 enters the pressure-charging hot blast furnace 51. After the pressure is balanced, close the sixteenth stop valve 36;

[0052] (3) Open the fourth stop valve 10, and the high-pressure gas in the second group of gas storage tanks enters the pressurized hot air furnace 51 until the pressure reaches the cold air pressure. Close the eighteenth stop valve 38 and the fourth stop valve 10, and the pressurization of the pressurized hot air furnace 51 is completed;

[0053] (4) Open the sixteenth stop valve 36 and the tenth stop valve 26, and the remaining medium and high pressure gas in the exhaust hot blast furnace 50 enters the first group of gas storage tanks. After the pressure is balanced, close the sixteenth stop valve 36 and the tenth stop valve 26;

[0054] (5) Open the twenty-second stop valve 42 to discharge the remaining low-pressure gas in the pressure-discharging hot blast furnace 50 into the chimney 47 through the flue gas branch pipe 53, and close the twenty-second stop valve 42 to complete the pressure relief of the pressure-discharging hot blast furnace 50.

[0055] In exhaust gas recovery mode B, when the blast furnace 52 uses oxygen-enriched blast, the exhaust gas not only contains high pressure energy but also high oxygen content. Mixing the exhaust gas with the combustion-supporting air helps to increase the combustion temperature. The operation of each component is as follows:

[0056] (1) Open the sixteenth stop valve 36 and the tenth stop valve 26, and the gas in the exhaust hot blast furnace 50 enters the first group of gas storage tanks. After the pressure is balanced, close the tenth stop valve 26;

[0057] (2) Open the fourth stop valve 10, and the gas in the exhaust hot blast furnace 50 enters the second group of gas storage tanks. After the pressure is balanced, close the sixteenth stop valve 36 and the fourth stop valve 10, and the exhaust gas recovery is completed;

[0058] (3) Open the twenty-second stop valve 42, and the remaining exhaust gas is discharged into the chimney 47 through the flue gas branch pipe 53, and the pressure relief of the hot air furnace 50 is completed;

[0059] (4) The seventh stop valve 18, the third pressure-stabilizing valve 19, the sixth stop valve 15 and the second pressure-stabilizing valve 16 are opened in sequence, and the oxygen-rich gas is mixed into the combustion air main pipe 12 and sent to the hot blast furnace for burning.

[0060] There are three main types of hot blast furnace pressure changes: conventional pressure change, pressure change with blower constant pressure plus air pressure change, and external air source pressure change. External air source pressure change can achieve disturbance-free furnace change. Among them, the working method of disturbance-free furnace change mode A is as follows:

[0061] (1) Open the third stop valve 7, start the air compressor 9, and charge the second group of gas storage tanks. When the pressure reaches the set pressure, stop the compressor and close the third stop valve 7 to complete the gas storage;

[0062] (2) Open the eighteenth stop valve 38 and the tenth stop valve 26, and the low-pressure gas stored in the first group of gas storage tanks enters the pressurized hot air furnace 51. When the pressure reaches equilibrium, close the tenth stop valve 26;

[0063] (3) Open the fourth stop valve 10, and the high-pressure gas in the second group of gas storage tanks enters the pressurized hot air furnace 51. When the pressure in the pressurized hot air furnace 51 is equal to the cold air pressure, close the eighteenth stop valve 38 and the fourth stop valve 10, and the pressurization of the pressurized hot air furnace 51 is completed.

[0064] The working method of the disturbance-free furnace change mode B is as follows:

[0065] (1) Open the ninth stop valve 24 and the fifth pressure-stabilizing valve 25, and use cold air to evenly and slowly pressurize the first group of gas storage tanks until the pressure in the gas storage tanks reaches the cold air pressure; close the ninth stop valve 24 and the fifth pressure-stabilizing valve 25, and the first group of gas storage tanks are pressurized with cold air to complete gas storage;

[0066] (2) Start the air compressor 9 and the first stop valve 3, and replenish the pressure of the first group of air storage tanks to reach the set pressure;

[0067] (3) The pressurized hot blast furnace 51 is pressurized using the gas stored in the first group of gas storage tanks. When the pressure in the pressurized hot blast furnace 51 reaches the cold air pressure, the pressurization is completed.

[0068] (4) Since the cold air takes a long time to store gas in the gas tank slowly, the pressure fluctuation of the cold air is minimized to the greatest extent.

[0069] In the above two disturbance-free furnace changing modes, the pressurized gas of the pressurized hot blast furnace 51 is entirely from the gas storage tank without diverting cold air, which does not cause hot blast pressure fluctuations and realizes disturbance-free furnace changing.

[0070] It should be noted that the cold air pressure stabilization mode can also be used for disturbance-free furnace replacement. Specifically, the working method of the cold air pressure stabilization mode is as follows:

[0071] (1) When the conventional charging and discharging method is used, the eighth stop valve 21 and the fourth pressure stabilizing valve 22 are opened, and the third check valve 23 only allows gas to flow out of the first group of gas storage tanks;

[0072] (2) Open the seventeenth stop valve 37 and the nineteenth stop valve 39. The gas in the first group of gas storage tanks and the cold air enter the pressurized hot air furnace 51 for pressurization at the same time. The gas storage tanks act as a pressure stabilizer to reduce the pressure fluctuation of the cold air.

[0073] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any equivalent changes or modifications made according to the essence of the present invention should be included in the scope of protection of the present invention.

Claims

1. A device for undisturbed hot blast stove replacement and exhaust gas recovery, comprising a plurality of hot blast stoves, one of which is in a pressurized state, another in a exhaust state, and the remaining hot blast stoves in an air supply state; blast furnaces, chimneys, and blowers are provided on the periphery of the hot blast stoves; the blast furnace is connected to all the hot blast stoves via a hot blast duct, the chimney is connected to all the hot blast stoves via a flue gas duct, and the blower is connected to all the hot blast stoves via a cold air duct; wherein, The flue gas duct includes a flue gas main pipe and several flue gas branches, and the flue gas main pipe is connected to the corresponding hot blast furnace through the corresponding flue gas branches; the cold air duct includes a cold air main pipe and several cold air branches, and the cold air main pipe is connected to the corresponding hot blast furnace through the corresponding cold air branches; a combustion air main pipe is also provided on one side of the cold air main pipe; the invention is characterized in that it also includes: Several groups of gas storage tanks are arranged in series and used as external gas sources. The gas storage tanks are connected to all hot blast furnaces through a first pipeline to provide exhaust gas recovery and pressurization functions for the hot blast furnaces; they are connected to the cold air main pipe through a second pipeline to supply cold air to the gas storage tanks; and they are connected to the combustion air main pipe through a third pipeline to supply oxygen-rich gas to the combustion air main pipe. The air compressor is connected to a plurality of gas storage tanks through a fourth pipeline and is used for filling the gas storage tanks with air.

2. The device for hot blast stove non-disturbance furnace replacement and exhaust gas recovery according to claim 1, characterized in that: The first pipeline includes a first main pipe connecting a plurality of gas storage tanks, and a plurality of first branch pipes connected to the first main pipe at one end and to the flue gas branch pipe at the other end, and a stop valve is provided on the first main pipe and each first branch pipe; The second pipeline includes a plurality of second branch pipes, one end of which is connected to the corresponding group of gas storage tanks and the other end is connected to the cold air main pipe, and each second branch pipe is provided with a stop valve and a pressure regulating valve; The third pipeline includes a third main pipe connected to the combustion air main pipe, and a plurality of third branch pipes connected to the third main pipe at one end and connected to the corresponding group of gas storage tanks at the other end. Each third branch pipe is equipped with a stop valve, a pressure regulating valve and a check valve. The fourth pipeline includes a fourth main pipe connected to the air compressor, and a plurality of fourth branch pipes, one end of which is connected to the fourth main pipe and the other end of which is connected to the corresponding group of air storage tanks.

3. The device for hot blast stove non-disturbance furnace replacement and exhaust gas recovery according to claim 2, characterized in that: A fifth pipeline is also provided between any group of gas storage tanks and all hot blast furnaces, which can simultaneously deliver cold air and gas in the gas storage tanks to the hot blast furnaces.

4. The device for hot blast stove non-disturbance furnace replacement and exhaust gas recovery according to claim 3, characterized in that: The fifth pipeline includes a fifth main pipe connected to the gas tank, and a fifth branch pipe connected to the fifth main pipe at one end and the corresponding cold air branch pipe at the other end. The fifth main pipe is provided with a shut-off valve, a pressure-stabilizing valve and a check valve, and each fifth branch pipe is provided with a shut-off valve.

5. The device for hot blast stove non-disturbance furnace replacement and exhaust gas recovery according to claim 1, characterized in that: Each group of gas storage tanks includes two gas storage tanks, one of which is connected to the first pipeline and the second pipeline, and the other is connected to the third pipeline and the fourth pipeline.

6. The device for hot blast stove non-disturbance furnace replacement and exhaust gas recovery according to claim 1, characterized in that: A stop valve is provided between two adjacent groups of gas storage tanks.

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