Blow-in air supply system and method for hydrogen-rich and carbon-rich circulating oxygen blast furnace

Abstract

The invention belongs to the technical field of blast furnace smelting, and particularly discloses a hydrogen-rich carbon circulating oxygen blast furnace blow-in air supply system and method.The system comprises a blast furnace, an air inlet header pipe, a smoke header pipe and a plurality of hot blast stoves, each hot blast stove communicates with a nitrogen inlet pipe and a cold air inlet pipe, and each hot blast stove is provided with an air outlet pipe; each air outlet pipe is communicated with an air outlet header pipe, the air outlet header pipe is communicated with a communicating bustle pipe, the high way is communicated with a plurality of air inlet branch pipes, the bustle pipe is communicated with the air inlet branch pipes, the air outlet header pipe is communicated with an air mixing pipe, the bottom of each hot blast stove is communicated with a smoke exhaust pipe, and each smoke exhaust pipe is communicated with a smoke header pipe. The flue gas header pipe is communicated with a flue gas branch pipe I, the flue gas branch pipe I is communicated with the blast furnace, the flue gas branch pipe I is communicated with a flue gas branch pipe II, the upper end of each hot blast stove is communicated with a flue gas inlet pipe, each flue gas inlet pipe is communicated with the flue gas branch pipe II, and the flue gas branch pipe I is provided with a circulating fan. Efficient temperature control and oxygen reduction are achieved, waste heat recycling is achieved, and safe, energy-saving and low-carbon blow-in is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of blast furnace smelting, and in particular to a hydrogen-rich carbon circulating oxygen blast furnace opening and air supply system and method. Background Art

[0002] my country's steel industry consumes a significant amount of coal resources, converting it into fuel in the form of coal gas. Traditional blast furnace ironmaking technology has achieved significant progress in production efficiency and energy utilization. Over 90% of the world's pig iron production is produced using this traditional blast furnace process. This process involves injecting hot air at 1000-1300°C (with an oxygen enrichment ratio below 10%) into the blast furnace through a hot blast furnace. The hot air then combusts with coke and injected pulverized coal in the tuyere's vortex zone, generating coal gas that moves upward and undergoes a complex heat exchange and reduction reaction with the descending ore, producing pig iron.

[0003] However, this heating method has the problem that the burning speed of the ignited wood is faster than that of the coke, and the volume decreases rapidly, causing the upper charge of the blast furnace to collapse quickly into the hearth, forming a low charge line, which will block the existing air flow channel, causing collapsed and suspended charge during the furnace opening process, affecting the process of rapid production at the furnace opening, consuming fuel and wasting time. Summary of the Invention

[0004] The purpose of the present invention is to provide a hydrogen-rich carbon circulating oxygen blast furnace opening air supply system and method to solve the problem that the oxygen content is too high when the blast furnace is opened and supplied with air, which causes the wood to burn too quickly, causing the furnace top charge to collapse quickly, forming air flow blockage, and thus affecting the furnace opening process.

[0005] In order to achieve the above-mentioned purpose, the basic scheme provided by the present invention is: a hydrogen-rich carbon cycle oxygen blast furnace opening and air supply system, comprising a blast furnace, an air inlet main pipe, a flue gas main pipe and a plurality of hot blast furnaces, each hot blast furnace is connected to a nitrogen inlet pipe and a cold air inlet pipe, each nitrogen inlet pipe is provided with a nitrogen inlet valve, each cold air inlet pipe is provided with a cold air inlet valve, each hot blast furnace is provided with an outlet pipe, each outlet pipe is provided with an outlet valve, each outlet pipe is respectively connected to the outlet main pipe, the outlet main pipe is provided with an air inlet valve, the outlet main pipe is connected to the surrounding pipe at one end away from the outlet pipe, and the high road is connected to a plurality of air inlets. The branch pipe and the surrounding pipe are connected with the air inlet branch pipe, the main air outlet pipe is connected with a mixing air pipe, and the mixing air pipe is provided with an air mixing valve. The bottom of each hot blast furnace is connected with a smoke exhaust pipe, and each smoke exhaust pipe is provided with a smoke exhaust valve. Each smoke exhaust pipe is connected with the flue gas main pipe. The flue gas main pipe is connected with a flue gas branch pipe 1, and the flue gas branch pipe 1 is connected with the blast furnace. The flue gas branch pipe 1 is provided with a smoke inlet valve 1, and the flue gas branch pipe 1 is connected with a flue gas branch pipe 2. The upper end of each hot blast furnace is connected with a smoke inlet pipe, and each smoke inlet pipe is connected with the flue gas branch pipe 2. Each smoke inlet pipe is provided with a smoke inlet valve 2, and the flue gas branch pipe 1 is provided with a circulating fan.

[0006] The working principle of the present invention is as follows: when the blast furnace is started, the air mixing valve is first opened to purge the blast furnace with nitrogen at room temperature to reduce the oxygen content in the blast furnace. When the oxygen content is less than 1%, the air mixing valve is closed, and the nitrogen inlet valve is opened to pass the nitrogen at room temperature into the hot blast furnace for heating. The heated hot nitrogen enters the gas outlet main pipe and enters the blast furnace through the air inlet branch pipe to perform high-temperature baking on the charge in the blast furnace. At the same time, the flue gas generated by the hot blast furnace when heating the nitrogen is discharged in two ways, one way enters the atmosphere and the other way enters the blast furnace for auxiliary baking. After the wood in the furnace is completely dry-distilled, the nitrogen inlet valve is closed, the cold air inlet valve is opened, and the hot blast furnace is used to heat the air. The heated air enters the blast furnace, and the charge starts to burn immediately. During the process, the oxygen content in the furnace is maintained at 20±1%. At the same time, the flue gas generated by the hot blast furnace when heating the air is discharged in two ways, one way enters the atmosphere and the other way enters the hot blast furnace for auxiliary heating. After the charge in the furnace drops rapidly, it means that the furnace start-up is completed, and normal load material can be added to the furnace to start smelting in the blast furnace.

[0007] The beneficial effects of the present invention are: this process significantly optimizes the efficiency and safety of blast furnace opening by scientifically controlling the gas medium and temperature changes. The initial nitrogen purge effectively reduces the oxygen content in the furnace to below 1%, avoiding the risk of combustible gas explosion; high-temperature nitrogen baking can quickly remove moisture from the charge, while preheating the furnace structure to reduce thermal stress damage; the hot blast furnace flue gas diversion design realizes the recycling of waste heat, which not only assists baking but also reduces energy consumption; after switching to hot air, the oxygen content is accurately maintained at 20±1%, ensuring that the charge is fully burned and avoids excessive oxidation, and the thermal efficiency is further enhanced in conjunction with flue gas recycling; the gas and temperature are dynamically controlled throughout the entire process, so that the charge distillation, combustion, and descent links are closely connected, shortening the furnace opening time by about 30%, and reducing fuel consumption by more than 15%, laying a high-efficiency, energy-saving, and low-emission process foundation for subsequent stable smelting.

[0008] Option 2, which is the preferred option of the basic option, is to install a gas analyzer on the blast furnace. The gas analyzer can monitor the oxygen content in the furnace in real time.

[0009] Option 3, which is the best option of Option 2, is to install a thermocouple on the blast furnace to monitor the temperature inside the furnace and the condition of the charge in real time.

[0010] Option 4, a preferred alternative to Option 3, uses a solenoid valve for the nitrogen inlet valve, while the cold air inlet valve, outlet valve, intake valve, air mixing valve, exhaust valve, smoke inlet valve 1, and smoke inlet valve 2 are all hydraulic valves. These valves, along with the gas analyzer, thermocouple, and circulating fan, are all electrically connected to a PLC controller. The PLC centrally controls the solenoid and hydraulic valves, and combines real-time data from the gas analyzer and thermocouple to achieve precise multi-valve linkage control. This significantly improves the safety, efficiency, and equipment stability of the blast furnace start-up process, while reducing manual operation errors and process risks caused by uncontrolled oxygen content and temperature.

[0011] Scheme 5: A method for opening and supplying air to a hydrogen-rich carbon circulating oxygen blast furnace. The specific steps for opening and supplying air to a blast furnace are as follows: S1: Place coke, wood, clean coke, empty coke and load charge into the blast furnace in sequence; S2: After the laying is completed, the air mixing valve and the air inlet valve are opened remotely to spray nitrogen at 25-30℃ into the blast furnace, and the nitrogen flow rate is reduced from 100m 3 / h gradually increase to 500m 3 / h, control the purge time to 10-30min; S3: Use a gas analyzer to detect the oxygen content in the blast furnace in real time. When the oxygen content is measured to be less than 0.8%, a detection signal is sent to the central control platform. After receiving the signal, the central control platform remotely closes the air mixing valve and the air inlet valve, and stops the nitrogen purge; S4: The nitrogen inlet valve is remotely opened through the central control platform to introduce nitrogen into the hot blast furnace, heating the nitrogen temperature from 25-30°C to 750-950°C. The air inlet valve is remotely opened through the central control platform to allow the heated hot nitrogen to enter the blast furnace. During the heating period, the flue gas generated in the hot blast furnace is discharged in two ways; S5: Increase the nitrogen flow rate from 200m 3 / h gradually increased to 1000m 3 / h, continuously inject the wood and starter charge in the blast furnace, and control the injection time to 4-8h. During the process, observe the wood distillation. After the wood is completely distilled, remotely close the air inlet valve and nitrogen inlet valve through the central control platform to stop the nitrogen supply; S6: The cold air inlet valve is remotely opened through the central control platform to introduce air into the hot blast furnace. The hot blast furnace heats the air to 1000±10℃. The air inlet valve is remotely opened through the central control platform to introduce the heated hot air into the blast furnace. The wood in the blast furnace begins to burn. The flue gas generated in the hot blast furnace during the heating period is discharged in two ways. S7: Increase the air volume from 300m 3 / h slowly increase to 1000m 3 / h, during the process, a gas analyzer is used to detect the oxygen content in the blast furnace, and dynamic regulation is performed to maintain the oxygen content at 20±1%; S8: Observe the downward movement of the top material line. If the top material line is moving downward steadily, proceed to the next step. If the top material line is not moving downward or is moving downward unsteadily, continue to slowly increase the air volume until the top material line is moving downward steadily, then proceed to the next step. S9: Rapidly increase the air volume to full air state, observe the charge situation in the blast furnace, and when the charge line on the top of the furnace drops rapidly, add normal load material, complete the blast furnace start-up work, and start blast furnace smelting operations.

[0012] When the furnace is opened, nitrogen is sent into the hot blast furnace, and when the temperature reaches above 1000°C, the blast furnace is fed to heat the charge. At the same time, the wood supporting the combustion in the hearth is subjected to oxygen-free dry distillation and carbonization to form charcoal. The wood that forms charcoal can quickly ignite coke after contact with air, and at the same time has a certain structural strength. In this process, harmful alkali metals such as potassium, sodium, zinc in the wood and moisture in the charge are quickly discharged out of the furnace through the high-temperature nitrogen; the full-wind state in step S9 is divided into two types. For a 400m³ blast furnace, the air volume in the full-wind state is 72,000-78,000 m³ / h, and for a 2500m³ blast furnace, the air volume in the full-wind state is 270,000-300,000 m³ / h. This method can be applied to both 400m³ and 2500m³ blast furnaces, and the air volume in the full-wind state also changes according to changes in the blast furnace.

[0013] Option 6, a preferred alternative to Option 5, involves splitting the exhaust gas into two routes in step S4: The hot nitrogen entering the blast furnace heats the charge, while the flue gas generated within the hot blast furnace is discharged into the atmosphere via the flue gas main. The flue gas from the hot blast furnace enters the flue gas main and then enters the blast furnace via flue gas branch pipe 1 to assist in baking. Reusing the waste flue gas from the hot blast furnace within the blast furnace, where it, along with the hot nitrogen, heats the charge and furnace walls, reduces nitrogen consumption and saves costs.

[0014] Option 7, a preferred alternative to Option 5, involves splitting the exhaust gas into two routes in step S6: Hot air entering the blast furnace is injected into the charge to aid combustion. The exhaust gas generated in the hot blast furnace is discharged into the atmosphere through the flue gas main pipe. The exhaust gas enters the flue gas main pipe and then enters the hot blast furnace through flue gas branch pipe 2 for auxiliary heating. The exhaust gas generated in the hot blast furnace is recycled back into the hot blast furnace to further heat the air, reducing energy consumption.

[0015] Option 8, a preferred alternative to Option 5, involves continuous system thermal tightening during the normal air supply in step S2 and the hot nitrogen bakeout and retort in step S5. This continuous thermal tightening effectively eliminates the risk of bolt loosening and gas leakage caused by thermal expansion under high-temperature conditions, ensuring system sealing and structural stability, reducing the frequency of unplanned maintenance shutdowns, and ensuring continuous and safe process operation.

[0016] Option 9, a preferred alternative to Option 6, requires the flue gas entering the blast furnace to have a temperature of 200-300°C and an oxygen content of less than 0.5%. Controlling the temperature and oxygen content of the incoming flue gas ensures sufficient combustion of the charge within the furnace and prevents excessive oxidation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a hydrogen-rich carbon circulating oxygen blast furnace opening and air supply system and method according to the present invention. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below through specific embodiments: The figure marks in the drawings of the specification include: 1. blast furnace, 2. exhaust main pipe, 3. flue gas main pipe, 4. hot blast furnace, 5. thermocouple, 6. nitrogen inlet pipe, 7. cold air inlet pipe, 8. nitrogen inlet valve, 9. cold air inlet valve, 10. exhaust pipe, 11. exhaust valve, 12. intake valve, 13. surrounding pipe, 14. air inlet branch pipe, 15. air mixing pipe, 16. air mixing valve, 17. smoke exhaust pipe, 18. smoke exhaust valve, 19. smoke branch pipe one, 20. smoke inlet valve one, 21. smoke branch pipe two, 22. smoke inlet pipe, 23. smoke inlet valve two, 24. circulating fan, 25. gas analyzer.

[0019] Example 1 like Figure 1 As shown: A hydrogen-rich carbon cycle oxygen blast furnace opening and air supply system, comprising a blast furnace 1, an outlet main pipe 2, a flue gas main pipe 3 and a plurality of hot blast furnaces 4, each hot blast furnace 4 is connected to a nitrogen inlet pipe 6 and a cold air inlet pipe 7, each nitrogen inlet pipe 6 is provided with a nitrogen inlet valve 8, each cold air inlet pipe 7 is provided with a cold air inlet valve 9, each hot blast furnace 4 is provided with an outlet pipe 10, each outlet pipe 10 is provided with an outlet valve 11, each outlet pipe 10 is connected to the ... nitrogen inlet valve 8, a nitrogen inlet valve 8, a cold air inlet valve 9, a nitrogen inlet valve 8, a cold air inlet valve 9, a nitrogen inlet valve 8, a cold air inlet valve 9, a nitrogen inlet valve 8, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 9, a cold air inlet valve 2 is connected, an air inlet valve 12 is provided on the air outlet main pipe 2, and the end of the air outlet main pipe 2 away from the air outlet pipe 10 is connected to the surrounding pipe 13. The blast furnace 1 is connected to a plurality of air inlet branches 14, and the surrounding pipes 13 are connected to the air inlet branches 14. The air outlet main pipe 2 is connected to a mixed air pipe 15, and the mixed air pipe 15 is provided with an air mixing valve 16. The bottom of each hot blast furnace 4 is connected to a smoke exhaust pipe 17, and each smoke exhaust pipe 17 is provided with a smoke exhaust valve 18. Each smoke exhaust pipe 17 is connected to the smoke main pipe 3. The flue gas main pipe 3 is connected with a flue gas branch pipe 19, which is connected to the blast furnace 1. The flue gas branch pipe 19 is provided with a smoke inlet valve 20. The flue gas branch pipe 19 is connected with a flue gas branch pipe 21. The upper end of each hot blast furnace 4 is connected with a smoke inlet pipe 22. Each smoke inlet pipe 22 is connected to the flue gas branch pipe 21. Each smoke inlet pipe 22 is provided with a smoke inlet valve 23. The flue gas branch pipe 19 is provided with a circulating fan 24. The blast furnace 1 is provided with a gas The analyzer 25 and the thermocouple 5, the nitrogen inlet valve 8 is a solenoid valve, the cold air inlet valve 9, the air outlet valve 11, the air inlet valve 12, the air mixing valve 16, the smoke exhaust valve 18, the smoke inlet valve 1 20, and the smoke inlet valve 2 23 are all hydraulic valves, and the nitrogen inlet valve 8, the cold air inlet valve 9, the air outlet valve 11, the air inlet valve 12, the air mixing valve 16, the smoke exhaust valve 18, the smoke inlet valve 1 20, the smoke inlet valve 2 23, the gas analyzer 25, the thermocouple 5, and the circulating fan 24 are all electrically connected to the PLC controller.

[0020] The implementation method of this embodiment is as follows: First, open the air mixing valve 16 to introduce room temperature nitrogen into the blast furnace 1 for purging. The gas analyzer 25 monitors the oxygen content in the furnace in real time. When the oxygen content drops below 1%, the PLC controller sends a signal to the central control platform. After receiving the signal, the central control platform closes the air mixing valve 16 and opens the nitrogen inlet valve 8 and the outlet valve 11 and inlet valve 12 of the hot blast furnace 4. After the nitrogen is heated in the hot blast furnace 4, it enters the blast furnace 1 through the outlet main pipe 2, the surrounding pipe 13 and the inlet branch pipe 14 to bake the furnace charge; at the same time, open the smoke exhaust valve 18 to remove the smoke generated by the hot blast furnace 4 through the circulating fan 24. Flue gas is split: one route enters the blast furnace 1 via flue gas branch pipe 19 to assist in baking, while the other route is discharged into the atmosphere via flue gas main pipe 3. Once the charge is dry distilled, the central control platform remotely closes nitrogen inlet valve 8 and opens cold air inlet valve 9, switching to hot air supply. Gas analyzer 25 dynamically adjusts air volume to maintain an oxygen concentration of 20±1% within the furnace. Flue gas is then split and recycled: one route enters the hot blast furnace 4 via flue gas branch pipe 21 to assist in heating, while the other route is discharged into the atmosphere via flue gas main pipe 3. When thermocouple 5 detects a rapid drop in charge, furnace start-up is determined to be complete and the smelting mode is switched on. The entire process is centrally controlled by a PLC controller, with all valves, sensors, and fans ensuring safe and efficient operation.

[0021] Example 2 A method for opening and supplying air to a hydrogen-rich carbon circulating oxygen blast furnace, wherein the specific steps for opening and supplying air to a blast furnace 1 are as follows: S1: Coke, wood, clean coke, empty coke, and load charge are placed in blast furnace 1 in sequence; S2: After the laying is completed, the air mixing valve 16 and the air inlet valve 12 are opened remotely to inject nitrogen at 25-30℃ into the blast furnace 1, and the nitrogen flow rate is reduced from 100m 3 / h gradually increase to 500m 3 / h, control the purge time to 10-30min, and continue to perform system hot tightening during the purge process; S3: The oxygen content in the blast furnace 1 is detected in real time using the gas analyzer 25. When the oxygen content is less than 0.8%, a detection signal is sent to the central control platform. After receiving the signal, the central control platform remotely closes the air mixing valve 16 and the air inlet valve 12 to stop the nitrogen purge. S4: The nitrogen inlet valve 8 is remotely opened through the central control platform to introduce nitrogen into the hot blast furnace 4, and the nitrogen temperature is heated from 25-30°C to 750-950°C. The air inlet valve 12 is remotely opened through the central control platform to allow the heated hot nitrogen to enter the blast furnace 1. During the heating period, the flue gas generated in the hot blast furnace 4 is discharged in two ways. The hot nitrogen entering the blast furnace 1 bakes the charge at high temperature. The flue gas generated in the hot blast furnace 4 is discharged into the atmosphere through the flue gas main pipe 3 in one way, and enters the flue gas main pipe 3 in the other way, and then enters the blast furnace 1 through the flue gas branch pipe 19 to assist in baking. The flue gas temperature is 200-300°C and the oxygen content is less than 0.5%; S5: Increase the nitrogen flow rate from 200m 3 / h gradually increased to 1000m 3 / h, continuously inject the wood and starter charge in the blast furnace 1, and control the injection time to 4-8h. Observe the wood distillation during the process. After the wood is completely distilled, remotely close the air inlet valve 12 and the nitrogen inlet valve 8 through the central control platform to stop the introduction of nitrogen. During the distillation process, continue to perform system thermal tightening; S6: The cold air inlet valve 9 is remotely opened through the central control platform to introduce air into the hot blast furnace 4. The hot blast furnace 4 heats the air to 1000±10℃. The air inlet valve 12 is remotely opened through the central control platform to introduce the heated hot air into the blast furnace 1. The wood in the blast furnace 1 begins to burn. During the heating period, the flue gas generated in the hot blast furnace 4 is discharged in two ways. The hot air entering the blast furnace 1 is sprayed on the charge to assist combustion. The flue gas generated in the hot blast furnace 4 is discharged into the atmosphere through the flue gas main pipe 3 on one side, and the other side enters the flue gas main pipe 3 and then enters the hot blast furnace 4 through the flue gas branch pipe 21 to assist heating. S7: Increase the hot air volume from 300m 3 / h slowly increase to 1000m 3 / h, during which the oxygen content in the blast furnace 1 is detected by a gas analyzer 25, and the oxygen content is dynamically controlled to maintain at 20±1%; S8: Observe the downward movement of the top material line. If the top material line is moving downward steadily, proceed to the next step. If the top material line is not moving downward or is moving downward unsteadily, continue to slowly increase the air volume until the top material line is moving downward steadily, then proceed to the next step. S9: Rapidly increase the air volume to full air state, observe the charge situation in blast furnace 1, and when the charge line on the top of the furnace drops rapidly, add normal load material, complete the opening of blast furnace 1, and start smelting operation of blast furnace 1.

[0022] The implementation method of this embodiment is as follows: When the 400m³ blast furnace is opened, first, nitrogen at 25°C is introduced into the blast furnace 1, and the nitrogen is gradually increased from 100m³ / h, and finally maintained at 500m³ / h, and purged for 25 minutes. The purged exhaust gas is discharged through the furnace top. When the oxygen content in the blast furnace 1 is detected to be 0.76%, the air mixing valve 16 is closed, and the nitrogen in the nitrogen inlet pipe 6 is introduced into the hot blast furnace 4 for heating. After heating to 700°C, it is introduced into the blast furnace 1 at 42,000m³ / h. The high-temperature nitrogen dry-distills the wood in the furnace and realizes the drying of the moisture of the opening charge. At the same time, a part of the flue gas generated in the hot blast furnace 4 enters the blast furnace for auxiliary baking. When the hot nitrogen is sprayed for 8 hours, it is observed that the furnace top charge line is steadily descending. At this time, the nitrogen inlet valve 8 and the air inlet valve 12 are closed to stop the nitrogen inlet valve 8 and the air inlet valve 12 ... Nitrogen is introduced into the furnace, followed by opening the cold air inlet valve 9 to allow air to flow into the hot blast furnace 4. The hot blast furnace 4 heats the air to 1000°C. During this process, a portion of the flue gas generated in the hot blast furnace 4 is returned to the hot blast furnace 4 for auxiliary heating. Hot air is then introduced into the blast furnace 1 at a rate of 300 m³ / h. The wood, formed into charcoal, immediately burns upon introduction of the hot air, igniting the coke and other furnace charges. The air volume is slowly increased to 1000 m³ / h to expedite the furnace start-up process. After about 10 minutes of hot air injection, the charge is observed to descend steadily. The air volume is then rapidly increased to 78,000 m³ / h, causing the charge to rapidly burn. The normal load (including sinter, pellets, coke, solvent, and auxiliary fuel) is then added, completing the blast furnace start-up and beginning the blast furnace steelmaking phase. This blast furnace start-up, from the initial start-up to the discharge of the first batch of molten iron and slag, took 12 hours, saving 6-8 hours compared to the original start-up method.

[0023] The above is only an embodiment of the present invention, and the common knowledge such as the specific structure and characteristics of the scheme is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A hydrogen-rich carbon cycle oxygen blast furnace opening and air supply system, characterized in that: The invention comprises a blast furnace (1), an exhaust main pipe (2), a flue gas main pipe (3) and a plurality of hot blast furnaces (4), each of the hot blast furnaces (4) is connected to a nitrogen inlet pipe (6) and a cold air inlet pipe (7), each of the nitrogen inlet pipe (6) is provided with a nitrogen inlet valve (8), each of the cold air inlet pipe (7) is provided with a cold air inlet valve (9), each of the hot blast furnaces (4) is provided with an exhaust pipe (10), each of the exhaust pipes (10) is provided with an exhaust valve (11), each of the exhaust pipes (10) is respectively connected to the exhaust main pipe (2), the exhaust main pipe (2) is provided with an exhaust valve (12), one end of the exhaust main pipe (2) away from the exhaust pipe (10) is connected to a surrounding pipe (13), the blast furnace (1) is connected to a plurality of air inlet branch pipes (14), the surrounding pipes (13) are connected to the air inlet branch pipe (14), the exhaust main pipe (2) is connected to a mixed gas outlet pipe (11), and the mixed gas outlet pipe (11) is connected to the mixed gas outlet pipe (11). The air duct (15) is provided with an air mixing valve (16) on the air mixing duct (15), the bottom of each hot blast furnace (4) is connected to a smoke exhaust pipe (17), each smoke exhaust pipe (17) is provided with a smoke exhaust valve (18), each smoke exhaust pipe (17) is connected to the flue gas main pipe (3), the flue gas main pipe (3) is connected to a smoke branch pipe 1 (19), the smoke branch pipe 1 (19) is connected to the blast furnace (1), the smoke branch pipe 1 (19) is provided with a smoke inlet valve 1 (20), the smoke branch pipe 1 (19) is connected to a smoke branch pipe 2 (21), the upper end of each hot blast furnace (4) is connected to a smoke inlet pipe (22), each smoke inlet pipe (22) is connected to the smoke branch pipe 2 (21), each smoke inlet pipe (22) is provided with a smoke inlet valve 2 (23), and the smoke branch pipe 1 (19) is provided with a circulating fan (24).

2. A hydrogen-rich carbon cycle oxygen blast furnace opening and air supply system according to claim 1, characterized in that: The blast furnace (1) is provided with a gas analyzer (25).

3. The hydrogen-rich carbon cycle oxygen blast furnace opening and air supply system according to claim 2 is characterized in that: The blast furnace (1) is provided with a thermocouple (5).

4. A hydrogen-rich carbon cycle oxygen blast furnace opening and air supply system according to claim 3, characterized in that: The nitrogen inlet valve (8) is a solenoid valve, and the cold air inlet valve (9), the air outlet valve (11), the air inlet valve (12), the air mixing valve (16), the smoke exhaust valve (18), the smoke inlet valve 1 (20), and the smoke inlet valve 2 (23) are all hydraulic valves. The nitrogen inlet valve (8), the cold air inlet valve (9), the air outlet valve (11), the air inlet valve (12), the air mixing valve (16), the smoke exhaust valve (18), the smoke inlet valve 1 (20), the smoke inlet valve 2 (23), the gas analyzer (25), the thermocouple (5), and the circulating fan (24) are all electrically connected to the PLC controller.

5. A method for opening and supplying air to a hydrogen-rich carbon cycle oxygen blast furnace, characterized in that: The specific steps of opening the blast furnace (1) and supplying air are as follows: S1: placing coke, wood, clean coke, empty coke, and load charge into the blast furnace (1) in sequence; S2: After the laying is completed, the air mixing valve (16) and the air inlet valve (12) are remotely opened to spray nitrogen at 25-30°C into the blast furnace (1), and the nitrogen flow rate is reduced from 100m 3 / h gradually increase to 500m 3 / h, control the purge time to 10-30min; S3: Using the gas analyzer (25) to detect the oxygen content in the blast furnace (1) in real time, and when the oxygen content is less than 0.8%, sending a detection signal to the central control platform, after the central control platform receives the signal, remotely closes the air mixing valve (16) and the air inlet valve (12), and stops nitrogen purge; S4: remotely opening the nitrogen inlet valve (8) through the central control platform, introducing nitrogen into the hot blast furnace (4), heating the nitrogen temperature from 25-30°C to 750-950°C, remotely opening the air inlet valve (12) through the central control platform, allowing the heated hot nitrogen to enter the blast furnace (1), and the flue gas generated in the hot blast furnace (4) during the heating period is discharged in two ways; S5: Increase the nitrogen flow rate from 200m 3 / h gradually increased to 1000m 3 / h, continuously spraying the wood and the starting charge in the blast furnace (1), controlling the spraying time to be 4-8h, observing the dry distillation of the wood during the process, and after the wood is completely dry distilled, remotely closing the air inlet valve (12) and the nitrogen inlet valve (8) through the central control platform to stop the introduction of nitrogen; S6: remotely opening the cold air inlet valve (9) through the central control platform to introduce air into the hot blast furnace (4), heating the air to 1000±10°C using the hot blast furnace (4), remotely opening the air inlet valve (12) through the central control platform to introduce the heated hot air into the blast furnace (1), and the wood in the blast furnace (1) begins to burn. During the heating period, the smoke generated in the hot blast furnace (4) is discharged in two ways; S7: Increase the hot air volume from 300m 3 / h slowly increase to 1000m 3 / h, during which the gas analyzer (25) is used to detect the oxygen content in the blast furnace (1), and the oxygen content is dynamically controlled to maintain at 20±1%; S8: Observe the downward movement of the top material line. If the top material line is moving downward steadily, proceed to the next step. If the top material line is not moving downward or is moving downward unsteadily, continue to slowly increase the air volume until the top material line is moving downward steadily, then proceed to the next step. S9: Rapidly increase the air volume to the full air state, observe the condition of the charge in the blast furnace (1), and when the charge line on the top of the furnace drops rapidly, add normal load charge, complete the opening of the blast furnace (1), and start the smelting operation of the blast furnace (1).

6. The method for opening and supplying air to a hydrogen-rich carbon cycle oxygen blast furnace according to claim 5, characterized in that: In step S4, the flue gas is discharged in two ways: the hot nitrogen gas entering the blast furnace (1) bakes the charge at high temperature, the flue gas generated in the hot blast furnace (4) is discharged into the atmosphere through the flue gas main pipe (3), and the other flue gas enters the flue gas main pipe (3) and then enters the blast furnace (1) through the flue gas branch pipe (19) for auxiliary baking.

7. The method for opening and supplying air to a hydrogen-rich carbon cycle oxygen blast furnace according to claim 5, characterized in that: In step S6, the flue gas is discharged in two ways: the hot air entering the blast furnace (1) is blown to the charge to assist combustion, the flue gas generated in the hot blast furnace (4) is discharged into the atmosphere through the flue gas main pipe (3), and the other flue gas enters the flue gas main pipe (3) and enters the hot blast furnace (4) through the second flue gas branch pipe (21) for auxiliary heating.

8. The method for opening and supplying air to a hydrogen-rich carbon cycle oxygen blast furnace according to claim 5, characterized in that: During the normal air supply in step S2 and the hot nitrogen baking and dry distillation in step S5, the system is continuously thermally tightened.

9. The method for opening and supplying air to a hydrogen-rich carbon cycle oxygen blast furnace according to claim 6, characterized in that: The flue gas entering the blast furnace (1) has a temperature of 200-300°C and an oxygen content of <0.5%.

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