A roof / bottom combined blowing system and method for a non-vacuum induction furnace

Abstract

The application discloses a top / bottom composite blowing system and method for a non-vacuum induction furnace, wherein a hydrogen conveying and adjusting gas path is communicated with an argon conveying and adjusting gas path, and then communicated with a hydrogen-argon mixed conveying and adjusting gas path, and the hydrogen-argon mixed conveying and adjusting gas path is communicated with a top blowing oxygen lance; a carbon dioxide conveying and adjusting gas path is communicated with the argon conveying and adjusting gas path, and then communicated with a carbon dioxide-argon mixed conveying and adjusting gas path, and the carbon dioxide-argon mixed conveying and adjusting gas path is communicated with a bottom of the non-vacuum induction furnace; and a control system is used to control the opening and closing of the hydrogen conveying and adjusting gas path, the carbon dioxide conveying and adjusting gas path, the argon conveying and adjusting gas path, the hydrogen-argon mixed conveying and adjusting gas path and the carbon dioxide-argon mixed conveying and adjusting gas path. The application reduces carbon emission per ton of steel, reduces the content of inclusions in the steel, improves the quality of carbon-containing steel materials, improves the steelmaking logistics level and reduces the smelting cost per ton of steel.

Description

Technical Field

[0001] This invention relates to iron and steel metallurgical technology, and more specifically, to a furnace top / bottom combined blowing system and method for non-vacuum induction furnaces. Background Technology

[0002] Traditional induction furnaces filter the exhaust gases from smelting before releasing them into the atmosphere. These gases contain a certain amount of carbon-containing greenhouse gases, causing environmental pollution. Furthermore, traditional induction furnace deoxidation methods employ precipitation deoxidation and diffusion deoxidation using deoxidizing alloy blocks (granules) and powders. Precipitation deoxidation is fast but produces many inclusions, while diffusion deoxidation produces fewer inclusions but is slower. These two methods are no longer adequate for the increasingly stringent requirements on the comprehensive performance of steel, especially regarding inclusions. Therefore, finding a denitrification, deoxidation, and carbon-enhancing technology that can reduce carbon emissions, remove oxygen from molten steel, and avoid secondary pollution of the steel has been a long-standing goal for metallurgists. Summary of the Invention

[0003] In view of the above-mentioned defects in the prior art, the purpose of this invention is to provide a furnace top / bottom combined blowing system and method for non-vacuum induction furnaces, which solves the drawbacks of existing deoxidation methods, reduces carbon emissions per ton of steel, reduces the content of inclusions in steel, improves the quality of carbon steel, improves the steelmaking logistics level, and reduces the smelting cost per ton of steel.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] On the one hand, a furnace top / bottom combined blowing system for a non-vacuum induction furnace includes a hydrogen delivery and regulating gas path, a carbon dioxide delivery and regulating gas path, an argon delivery and regulating gas path, a hydrogen-argon mixed delivery and regulating gas path, a carbon dioxide-argon mixed delivery and regulating gas path, and a control system.

[0006] The hydrogen delivery and regulating gas path is connected to the argon delivery and regulating gas path, and is further connected to the hydrogen-argon mixed delivery and regulating gas path, which is connected to the top-blown oxygen lance.

[0007] The carbon dioxide delivery and regulating gas path is connected to the argon delivery and regulating gas path, and then connected to the carbon dioxide-argon mixed delivery and regulating gas path. The carbon dioxide-argon mixed delivery and regulating gas path is connected to the furnace bottom of the non-vacuum induction furnace.

[0008] The control system is used to control the opening and closing of the hydrogen delivery and regulation gas path, the carbon dioxide delivery and regulation gas path, the argon delivery and regulation gas path, the hydrogen-argon mixed delivery and regulation gas path, and the carbon dioxide-argon mixed delivery and regulation gas path.

[0009] Preferably, the hydrogen delivery and regulating gas path includes a hydrogen source and a first manual ball valve, a second manual ball valve, a first one-way check valve, a first fast electromagnetic shut-off valve, a first pressure transmitter, a first mass flow meter, a first flow regulating valve, and a first check valve that are sequentially connected to the hydrogen source.

[0010] The second manual ball valve is equipped with a first pointer-type pressure gauge.

[0011] Preferably, the carbon dioxide delivery and regulating gas path includes a carbon dioxide gas source and a third manual ball valve, a fourth manual ball valve, a second one-way check valve, a second fast electromagnetic shut-off valve, a second pressure transmitter, a second mass flow meter, a second flow regulating valve, and a second check valve that are sequentially connected to the carbon dioxide gas source.

[0012] The fourth manual ball valve is equipped with a second pointer-type pressure gauge.

[0013] Preferably, the argon gas delivery and regulation path includes an argon gas source, a fifth manual ball valve and a sixth manual ball valve connected in sequence to the argon gas source, and a top blowing path and a bottom blowing path connected to the sixth manual ball valve.

[0014] The sixth manual ball valve is equipped with a third pointer-type pressure gauge.

[0015] Preferably, the top-blowing air path includes a third fast electromagnetic shut-off valve, a third pressure transmitter, a third mass flow meter, a third flow regulating valve, and a third check valve connected in sequence.

[0016] Preferably, the bottom blowing air path includes a fourth fast electromagnetic shut-off valve, a fourth pressure transmitter, a fourth mass flow meter, a fourth flow regulating valve, and a fourth check valve connected in sequence.

[0017] Preferably, the hydrogen-argon mixed delivery and regulating gas path includes a hydrogen-argon mixing package connected to the first check valve and the third check valve, and a seventh manual ball valve, a fifth check valve, a fifth fast electromagnetic shut-off valve, an eighth manual ball valve and a first anti-backfire valve connected in sequence to the hydrogen-argon mixing package.

[0018] The first backfire prevention valve is connected to the top-blown oxygen lance.

[0019] Preferably, the carbon dioxide-argon gas mixing and regulating gas path includes a carbon dioxide-argon gas mixing package connected to the second check valve and the fourth check valve, and a ninth manual ball valve, a sixth check valve, a sixth fast electromagnetic shut-off valve, a tenth manual ball valve and a second backfire prevention valve connected in sequence to the carbon dioxide-argon gas mixing package.

[0020] The second backfire prevention valve is connected to the bottom of the non-vacuum induction furnace via a bottom-blowing element.

[0021] Preferably, the hydrogen-argon mixed gas delivery and regulating gas path is provided with a compressed air delivery and regulating gas path;

[0022] The compressed air delivery and regulating circuit includes a compressed air source, and an eleventh manual ball valve, a twelfth manual ball valve, a seventh fast electromagnetic shut-off valve, and a third one-way check valve that are sequentially connected to the compressed air source.

[0023] The third one-way check valve is sequentially connected to the fifth fast electromagnetic shut-off valve, the eighth manual ball valve, and the first anti-backfire valve;

[0024] The twelfth manual ball valve is equipped with a fourth pointer-type pressure gauge.

[0025] Preferably, the carbon dioxide-argon gas mixing and regulating gas path is provided with a compressed air supply and regulating gas path;

[0026] The compressed air delivery and regulating circuit includes a compressed air source, and an eleventh manual ball valve, a twelfth manual ball valve, a seventh fast electromagnetic shut-off valve, and a third one-way check valve that are sequentially connected to the compressed air source.

[0027] The third one-way check valve is sequentially connected to the sixth fast electromagnetic shut-off valve, the tenth manual ball valve, and the second anti-backfire valve;

[0028] The twelfth manual ball valve is equipped with a fourth pointer-type pressure gauge.

[0029] Preferably, it also includes a gas leak detection alarm device for detecting gas leaks.

[0030] Preferably, it also includes top-blown replacement / purge air passages and bottom-blown replacement / purge air passages;

[0031] The top-blown displacement / purge gas path is connected to the hydrogen delivery and regulating gas path and the argon delivery and regulating gas path;

[0032] The bottom-blowing replacement / purge gas path is connected to the carbon dioxide delivery and regulating gas path and the argon delivery and regulating gas path.

[0033] On the other hand, a top / bottom combined blowing method for a non-vacuum induction furnace achieves the following process through the aforementioned top / bottom combined blowing system for a non-vacuum induction furnace:

[0034] The first manual ball valve, the second manual ball valve, the first one-way check valve, the first fast electromagnetic shut-off valve, the first pressure transmitter, the first mass flow meter, the first flow regulating valve, and the first check valve are opened in sequence to allow hydrogen to enter the hydrogen-argon mixture package.

[0035] The third manual ball valve, the fourth manual ball valve, the second one-way check valve, the second fast electromagnetic shut-off valve, the second pressure transmitter, the second mass flow meter, the second flow regulating valve, and the second check valve are opened in sequence to allow carbon dioxide to enter the carbon dioxide-argon mixture package.

[0036] Open the fifth manual ball valve and the sixth manual ball valve in sequence, as well as the top blowing gas path and the bottom blowing gas path, so that argon gas enters the hydrogen-argon mixture and the carbon dioxide-argon mixture respectively;

[0037] The seventh manual ball valve, the fifth check valve, the fifth fast electromagnetic shut-off valve, the eighth manual ball valve, and the first anti-backfire valve are opened in sequence, so that the hydrogen-argon mixture in the hydrogen-argon mixture package is blown into the molten steel from the top of the non-vacuum induction furnace through the top-blown oxygen lance.

[0038] The ninth manual ball valve, the sixth check valve, the sixth fast electromagnetic shut-off valve, the tenth manual ball valve, and the second anti-backfire valve are opened in sequence, so that the carbon dioxide-argon mixture in the carbon dioxide-argon mixture package is blown into the molten steel from the bottom of the non-vacuum induction furnace through the bottom blowing element.

[0039] The gas supply intensity of the top-blown oxygen lance and the bottom-blown element are both 100-500 L / t·min, and the gas pressure is both 0.1-1.0 MPa;

[0040] The mixing gas ratio of the top-blown oxygen lance and the bottom-blown element is (0-100%) / (100-0%).

[0041] This invention provides a top / bottom combined blowing system and method for non-vacuum induction furnaces. Utilizing two gases—a hydrogen-containing gas and a carbon-containing gas—the system blows these gases into molten steel to achieve denitrification, deoxidation, and carbonization. The carbon-containing gas reacts with the hydrogen-containing gas in the molten steel to produce solid carbon and water vapor, effectively treating smelting waste gas and adding carbon without polluting the molten steel. The hydrogen-containing gas reacts with oxygen in the molten steel to produce water vapor, which, being gaseous, escapes from the molten steel without contaminating it. Some unreacted carbon-containing gas and water vapor rise to the surface, carrying nitrogen bubbles in the molten steel to the surface, thus achieving denitrification. Therefore, using hydrogen and carbon dioxide gases for denitrification, deoxidation, and carbonization of molten steel is an effective method for producing clean, high-quality carbon steel. In addition, using hydrogen-containing and carbon-containing gases for denitrification, deoxidation, and carbon enrichment has several advantages: first, it reduces the total carbon emissions per ton of steel and the amount of carbon alloys used; second, the products of denitrification, deoxidation, and carbon enrichment do not pollute the molten steel, reducing the content of inclusions in the steel and improving the quality of carbon steel; and third, the cost of hydrogen-containing gases is much lower than the cost of deoxidizing alloys, so the cost per ton of steel will be greatly reduced by using hydrogen-containing gases for deoxidation. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the frame of the furnace top / bottom composite blowing system of the present invention;

[0043] Figure 2 This is a schematic diagram of the gas path of the furnace top / bottom combined blowing system of the present invention;

[0044] Figure 3 This is a schematic diagram of the bottom blowing element being integrated in the furnace top / bottom combined blowing system of the present invention;

[0045] Figure 4 This is a schematic diagram of the bottom blowing element in the furnace top / bottom composite blowing system of the present invention, which adopts a split type. In this diagram, (a) is a special bottom blowing element brick, (b) is a slit with a thickness of 0.3 mm, (c) is a slit with a thickness of 0.4 mm, and (d) is a slit with a thickness of 0.4 mm.

[0046] Figure 5 This is a schematic diagram of the top-blown oxygen lance in the furnace top / bottom combined blowing system of the present invention. Detailed Implementation

[0047] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0048] Combination Figure 1As shown, the present invention provides a furnace top / bottom combined blowing system for a non-vacuum induction furnace, comprising a hydrogen delivery and regulating gas path 10, a carbon dioxide delivery and regulating gas path 20, an argon delivery and regulating gas path 30, a hydrogen-argon mixed delivery and regulating gas path 40, a carbon dioxide-argon mixed delivery and regulating gas path 50, and a control system.

[0049] The hydrogen delivery and regulating gas path 10 is connected to the argon delivery and regulating gas path 30, and then connected to the hydrogen-argon mixed delivery and regulating gas path 40. The hydrogen-argon mixed delivery and regulating gas path is connected to the top-blown oxygen lance 100.

[0050] The carbon dioxide conveying and regulating gas path 20 is connected to the argon conveying and regulating gas path 30, and then connected to the carbon dioxide-argon mixed conveying and regulating gas path 50. The carbon dioxide-argon mixed conveying and regulating gas path 50 is connected to the furnace bottom of the non-vacuum induction furnace 200.

[0051] Based on a full consideration of the characteristics of steelmaking deoxidation technology, and combined with the characteristics of hydrogen-containing gas, reasonable technical parameters were determined, and gas regulation and control for denitrification, deoxidation, and carbonization of molten steel were designed and manufactured for non-vacuum induction furnaces, including top blowing of hydrogen-containing gas or hydrogen-argon mixture and bottom blowing of carbon dioxide-carbon dioxide-argon mixture.

[0052] The control system is used to control the opening and closing of the hydrogen delivery and regulation gas path 10, the carbon dioxide delivery and regulation gas path 20, the argon delivery and regulation gas path 30, the hydrogen-argon mixed delivery and regulation gas path 40, and the carbon dioxide-argon mixed delivery and regulation gas path 50.

[0053] The control system consists of a PLC, a touch screen (for operation and monitoring), power supply and distribution, a gas leak alarm controller, data signal acquisition, and actuators. When the system is in operation, first close the main power circuit breaker QF0 to connect the main power supply, and the power indicator light will illuminate. Close QF2 to power on the PLC and touch screen. Close circuit breakers QF2-QF4 (emergency stop in reset state) to ensure normal power supply to the DC control and actuators, and normal connection of the control circuit. During this process, the PLC, touch screen, and alarm system automatically start and perform self-test scans. After completion, the system enters standby mode.

[0054] The control system's operation panel features a power indicator, an emergency stop button (with key reset and locking function), and an operation display touchscreen. Normal operation is performed via the touchscreen.

[0055] The control system consists of three parts: process data setting, pre-operation pipeline purging, and jet purging operation. It supports manual intervention in any state and has a one-key reset function, which means that pressing the master reset button will shut down all solenoid valves.

[0056] The furnace top / bottom combined blowing system of the present invention also includes a top blowing replacement / purge gas path 60 and a bottom blowing replacement / purge gas path 70.

[0057] The top-blown replacement / purge gas path 60 is connected to the hydrogen delivery and regulating gas path 10 and the argon delivery and regulating gas path 30.

[0058] The bottom-blowing replacement / purge gas path 70 is connected to the carbon dioxide delivery and regulating gas path 20 and the argon delivery and regulating gas path 30.

[0059] Combination Figure 1 and Figure 2 As shown, the hydrogen delivery and regulating gas path 10 includes a hydrogen source 101 and a first manual ball valve 102, a second manual ball valve 103, a first one-way check valve 104, a first fast electromagnetic shut-off valve 105, a first pressure transmitter 106, a first mass flow meter 107, a first flow regulating valve 108, and a first check valve 109 connected in sequence to the hydrogen source 101; the second manual ball valve 103 is equipped with a first pointer-type pressure gauge 110.

[0060] The carbon dioxide delivery and regulating gas path 20 includes a carbon dioxide gas source 201 and a third manual ball valve 202, a fourth manual ball valve 203, a second one-way check valve 204, a second fast electromagnetic shut-off valve 205, a second pressure transmitter 206, a second mass flow meter 207, a second flow regulating valve 208, and a second check valve 209 connected in sequence to the carbon dioxide gas source 201; the fourth manual ball valve 203 is equipped with a second pointer-type pressure gauge 210.

[0061] The argon gas delivery and regulation circuit 30 includes an argon gas source 301, a fifth manual ball valve 302 and a sixth manual ball valve 303 connected in sequence to the argon gas source 301, and a top blowing circuit and a bottom blowing circuit connected to the sixth manual ball valve 303; the sixth manual ball valve 303 is equipped with a third pointer pressure gauge 304.

[0062] The top-blowing air path includes a third fast electromagnetic shut-off valve 305, a third pressure transmitter 306, a third mass flow meter 307, a third flow regulating valve 308, and a third check valve 309 connected in sequence.

[0063] The bottom blowing air path includes a fourth fast electromagnetic shut-off valve 310, a fourth pressure transmitter 311, a fourth mass flow meter 312, a fourth flow regulating valve 313, and a fourth check valve 314 connected in sequence.

[0064] The hydrogen-argon mixed gas delivery and regulating gas path 40 includes a hydrogen-argon mixing package 401 connected to a first check valve 109 and a third check valve 309, and a seventh manual ball valve 402, a fifth check valve 403, a fifth fast electromagnetic shut-off valve 404, an eighth manual ball valve 405 and a first anti-backfire valve 406 connected in sequence to the hydrogen-argon mixing package 401; the first anti-backfire valve 406 is connected to a top-blown oxygen lance 100, which blows the mixed gas into the molten steel from the top of the non-vacuum induction furnace 200.

[0065] The carbon dioxide-argon gas mixing and regulating gas path 50 includes a carbon dioxide-argon gas mixing package 501 connected to the second check valve 209 and the fourth check valve 314, and a ninth manual ball valve 502, a sixth check valve 503, a sixth fast electromagnetic shut-off valve 504, a tenth manual ball valve 505 and a second anti-backfire valve 506 connected in sequence to the carbon dioxide-argon gas mixing package 501; the second anti-backfire valve 506 is connected to the bottom of the non-vacuum induction furnace 200 through the bottom blowing element 300, and the mixed gas is blown into the molten steel from the bottom of the non-vacuum induction furnace 200.

[0066] Compressed air supply and regulation channels 80 are provided on the hydrogen-argon mixed gas supply and regulation channel 40 and the carbon dioxide-argon mixed gas supply and regulation channel 50.

[0067] The compressed air delivery and regulating circuit 80 includes a compressed air source 1, and an eleventh manual ball valve 2, a twelfth manual ball valve 3, a seventh fast electromagnetic shut-off valve 4, and a third one-way check valve 5 connected in sequence to the compressed air source 1; the twelfth manual ball valve 3 is equipped with a fourth pointer-type pressure gauge 6.

[0068] The third one-way check valve 5 is connected in sequence to the fifth fast electromagnetic shut-off valve 404, the eighth manual ball valve 405 and the first backfire prevention valve 406 to form a top-blowing gas path.

[0069] The third one-way check valve 5 is then connected in sequence to the sixth fast electromagnetic shut-off valve 504, the tenth manual ball valve 505, and the second backfire prevention valve 506 to form a bottom blowing air path.

[0070] The function of the compressed air delivery and regulating air path 80 is to clear the blockage of the top-blowing oxygen lance 100 or the bottom-blowing element 300 by compressed air should a blockage occur during the test.

[0071] For safety, the furnace top / bottom combined blowing system of the present invention also includes a gas leak detection alarm device 400 for detecting gas leaks. Once a gas leak occurs, the gas leak detection alarm device 400 will issue an alarm.

[0072] Combination Figure 3 and Figure 4As shown, there are two types of bottom blowing elements 300, one of which is an integrated bottom blowing element (such as...). Figure 3 As shown), the first type is made of high-temperature resistant, non-magnetic stainless steel, with a slit-type nozzle for the bottom blowing element, encased in chromium corundum castable; the second type is a split-type bottom blowing element (such as...). Figure 4 As shown), the blow nozzle is a slit type, the bottom blowing element is made of chromium corundum, high-temperature resistant non-magnetic stainless steel, and the bottom blowing element brick is made of chromium corundum castable.

[0073] Combination Figure 5 As shown, the top-blown oxygen lance 100 is made of non-magnetic stainless steel tube 7 and encased in corundum castable 8.

[0074] The present invention also provides a furnace top / bottom combined blowing method for non-vacuum induction furnaces, wherein the following processes are achieved through the furnace top / bottom combined blowing system of the present invention for non-vacuum induction furnaces:

[0075] The first manual ball valve 102, the second manual ball valve 103, the first one-way check valve 104, the first fast electromagnetic shut-off valve 105, the first pressure transmitter 106, the first mass flow meter 107, the first flow regulating valve 108, and the first check valve 109 are opened in sequence to allow hydrogen to enter the hydrogen-argon mixture package 401.

[0076] Open the third manual ball valve 202, the fourth manual ball valve 203, the second one-way check valve 204, the second fast electromagnetic shut-off valve 205, the second pressure transmitter 206, the second mass flow meter 207, the second flow regulating valve 208, and the second check valve 209 in sequence to allow carbon dioxide to enter the carbon dioxide-argon mixture package 501.

[0077] Open the fifth manual ball valve 302 and the sixth manual ball valve 303 in sequence, as well as the top blowing gas path and the bottom blowing gas path, so that argon gas enters the hydrogen-argon mixture package 401 and the carbon dioxide-argon mixture package 501 respectively.

[0078] The seventh manual ball valve 402, the fifth check valve 403, the fifth quick electromagnetic shut-off valve 404, the eighth manual ball valve 405, and the first anti-backfire valve 406 are opened in sequence, so that the hydrogen-argon mixture in the hydrogen-argon mixture package 401 is blown into the molten steel from the top of the non-vacuum induction furnace 200 through the top-blown oxygen lance 100.

[0079] The ninth manual ball valve 502, the sixth check valve 503, the sixth fast electromagnetic shut-off valve 504, the tenth manual ball valve 505, and the second anti-backfire valve 506 are opened in sequence, so that the carbon dioxide-argon mixture in the carbon dioxide-argon mixture package 501 is blown into the molten steel from the bottom of the non-vacuum induction furnace 200 through the bottom blowing element 300.

[0080] Since hydrogen and carbon-containing gases are flammable and hazardous gases, an argon gas system is used to purge and replace the gases remaining in the pipeline through top-blowing replacement / purging gas path 60 and bottom-blowing replacement / purging gas path 70. This prevents the oxygen in the air remaining in the pipeline from interfering with the experimental results and causing an explosion. Details are as follows:

[0081] Before the experiment, close the valves of hydrogen source 101 and carbon dioxide source 201, and then sequentially open the following valves: fifth manual ball valve 302, sixth manual ball valve 303, eighth quick-acting electromagnetic shut-off valve 601, seventh check valve 602, first pressure transmitter 106, first mass flow meter 107, first flow regulating valve 108, first check valve 109, hydrogen-argon mixing tank 401, seventh manual ball valve 402, fifth check valve 403, fifth quick-acting electromagnetic shut-off valve 404, eighth manual ball valve 405, first backfire prevention valve 406, and top-blown oxygen lance 100.

[0082] Then, sequentially open the ninth fast electromagnetic shut-off valve 701, the eighth check valve 702, the second pressure transmitter 206, the second mass flow meter 207, the second flow regulating valve 208, the second check valve 209, the carbon dioxide-argon mixture 501, the ninth manual ball valve 502, the sixth check valve 503, the sixth fast electromagnetic shut-off valve 504, the tenth manual ball valve 505, the second backfire prevention valve 506, and the bottom blowing element 300.

[0083] After cleaning and replacement, close the corresponding valves to ensure that no air remains in the pipeline.

[0084] Similarly, the argon gas pipeline needs to be cleaned and purged before the experiment, and the operation steps are the same as those for cleaning the hydrogen and carbon dioxide gas pipelines.

[0085] In the furnace top / bottom combined blowing method of the present invention, the gas supply intensity of the top blowing oxygen lance 100 and the bottom blowing element 300 are both 100 to 500 L / t·min, and the gas pressure is both 0.1 to 1.0 MPa.

[0086] The mixed gas ratio of the top-blown oxygen lance 100 and the bottom-blown element 300 is (0-100%) / (100-0%).

[0087] The ratio of argon to hydrogen is dynamically adjusted based on different oxygen contents; when the oxygen content is high, the proportion of hydrogen in the argon and hydrogen mixture is high.

[0088] The oxygen content is dynamically adjusted by varying the ratio of argon and carbon dioxide. When the oxygen content is high, the ratio of carbon dioxide in argon and carbon dioxide is low.

[0089] The gas pressure varies depending on the furnace condition. This invention uses a 200Kg non-vacuum induction furnace, and the gas pressure is set to 0.2MPa. Fine adjustments are required depending on the amount of gas added.

[0090] The top of the non-vacuum induction furnace 200 is equipped with an argon seal to ensure that the pressure inside the furnace is slightly positive.

[0091] The experimental procedure is as follows:

[0092] I. Preparatory Work

[0093] 1. Power on the jetting system: Confirm that all solenoid valves are in the "closed" state and that all manual valves are in the "closed" state.

[0094] 2. Open the manual valve of the hydrogen cylinder and adjust the pressure at the outlet to 0.2 MPa.

[0095] 3. Open the manual valve of the carbon dioxide cylinder and adjust the pressure at the outlet to 0.2 MPa.

[0096] 4. Open the first manual ball valve 102 in the gas distribution cabinet.

[0097] 5. Open the fifth manual ball valve 302 in the gas distribution cabinet and adjust the outlet pressure to 0.15-0.2MPa.

[0098] 6. Open the eleventh manual ball valve 2 in the gas distribution cabinet.

[0099] 7. Open the hydrogen-argon mixture package 401, the carbon dioxide-argon mixture package 501, the seventh manual ball valve 402, and the ninth manual ball valve 502.

[0100] 8. Confirm that the gas leak detection alarm device 400 is working properly and there is no alarm.

[0101] II. Pipeline Purging

[0102] 1. Select "Setup Screen" in the system operation screen.

[0103] 2. Set the ratio of argon to hydrogen to 100:0.

[0104] 3. Set the ratio of argon to carbon dioxide to 100:0.

[0105] 4. Set the mixed gas flow rate to 50.

[0106] 5. Select "Purge Pipeline Screen".

[0107] 6. Press “Purge Start”: Confirm that the eighth fast electromagnetic shut-off valve 601, the third fast electromagnetic shut-off valve 305, the ninth fast electromagnetic shut-off valve 701, the fourth fast electromagnetic shut-off valve 310, and the sixth fast electromagnetic shut-off valve 504 are open.

[0108] 7. Open the eighth manual ball valve 405 and the tenth manual ball valve 505 next to the furnace.

[0109] 8. Confirm that the top-blown oxygen lance 100 and the bottom-blown element 300 are emitting air.

[0110] 9. After 3 minutes, close the eighth manual ball valve 405 and the tenth manual ball valve 505 next to the furnace.

[0111] 10. Press the "Purge End" button.

[0112] III. Steelmaking Operations

[0113] 1. Load the materials, turn on the power to heat up, install an argon seal on the furnace opening and introduce argon gas.

[0114] 2. Turn on the bottom blowing system, set the argon / carbon dioxide ratio to 100:0, and adjust the pressure to 0.1 MPa. This is to prevent clogging of the bottom blowing components during the steelmaking process.

[0115] 3. Open the tenth manual ball valve 505 next to the furnace.

[0116] 4. Melt and heat to the required process temperature of 1580℃~1610℃.

[0117] 5. Temperature measurement to determine oxygen content (250-350 ppm); sampling to determine nitrogen content (150-250 ppm); sampling to determine carbon content (30-70 ppm).

[0118] 6. Set the insulation power.

[0119] IV. One-button blowing

[0120] 1. Enter the "Setup Screen"

[0121] ① Set the mixture ratio based on the measured oxygen content.

[0122] ② Set the hydrogen and argon pressures according to the amount of main raw materials loaded.

[0123] ③ Set the mixed gas flow rate according to the loading amount.

[0124] ④ Set the blowing time based on the measured oxygen content.

[0125] 2. Press "Start Purge" to confirm that the first fast electromagnetic shut-off valve 105, the fifth fast electromagnetic shut-off valve 404, the third fast electromagnetic shut-off valve 305, the second fast electromagnetic shut-off valve 205, the sixth fast electromagnetic shut-off valve 504, and the fourth fast electromagnetic shut-off valve 310 are open, and the eighth fast electromagnetic shut-off valve 601 and the ninth fast electromagnetic shut-off valve 701 are closed. The purging time countdown will then begin.

[0126] ① Slowly open the eighth manual ball valve 405 and the tenth manual ball valve 505 next to the furnace to the appropriate opening degree, confirm that the nozzle of the top-blown oxygen lance 100 is flaming, and confirm that there are bubbles rising out of the molten steel.

[0127] ② Lower the top-blown oxygen lance 100mm into the molten steel, inserting it to a depth of 100-400mm from the bottom of the furnace.

[0128] ③ Confirm that the flow rate and pressure are normal.

[0129] ④ When the countdown reaches zero, confirm that the eighth fast electromagnetic shut-off valve 601 and the ninth fast electromagnetic shut-off valve 701 are open, and the first fast electromagnetic shut-off valve 105 and the second fast electromagnetic shut-off valve 205 are closed.

[0130] ⑤ Purge argon gas for 2-5 minutes to empty the hydrogen gas in the storage tank and pipeline.

[0131] ⑥ Close the eighth manual ball valve 405 and the tenth manual ball valve 505 near the furnace.

[0132] ⑦ Temperature measurement and oxygen determination sampling.

[0133] 3. End

[0134] The results of hydrogen injection experiments in a non-vacuum induction furnace for deoxidation, denitrogenation, and carbon enrichment of molten steel are shown in Table 1 below.

[0135] Table 1

[0136]

[0137] In conjunction with the present invention, the following three embodiments are given.

[0138] Ensure consistent furnace conditions throughout the entire injection process.

[0139] Example 1

[0140] The initial oxygen content was 327.2 ppm, the initial nitrogen content was 189.5 ppm, the initial carbon content was 39.1 ppm, the molten steel temperature was 1587℃, and the loading amount was 170 kg.

[0141] Preliminary pipeline purging: Set the argon / hydrogen and argon / carbon dioxide ratios to 100 / 0, pressure to 0.2 MPa, and flow rate to 100 L / min. Open the furnace-side manual valve and press the one-button purging button. After purging for 2 minutes, close the furnace-side manual valve, and then close the one-button purging button.

[0142] Load the fuel, install the argon seal, power on and heat up. After a certain amount of molten pool forms at the bottom, set the bottom blowing mixture ratio to argon / carbon dioxide 100 / 0, flow rate to 5L / min, pressure to 0.1MPa, and blowing time to 30 minutes. Press the one-button blowing button and slowly open the furnace-side manual valve, adjusting the opening degree according to the churning situation until fully open. After all the fuel has melted, close the furnace-side manual valve and turn off the one-button blowing. Measure the temperature and oxygen content, and adjust the temperature to 1590℃±10℃.

[0143] Process parameters are set as follows: Argon and hydrogen pressure: 0.2 MPa; Argon and carbon dioxide pressure: 0.2 MPa; Mixed gas flow rate: 15 L / min; Injection time: 8 minutes; The mixing ratio is dynamically adjusted during the injection process. Initially, the argon / hydrogen ratio is 10% / 90%, and the argon / carbon dioxide ratio is 95% / 5%. After 3 minutes of injection, the argon / hydrogen ratio is adjusted to 30% / 70%, and the argon / carbon dioxide ratio to 70% / 30%. After 6 minutes of injection, the argon / hydrogen ratio is adjusted to 50% / 50%, and the argon / carbon dioxide ratio to 50% / 50%. After 7 minutes of injection, the argon / hydrogen ratio is adjusted to 70% / 30%, and the argon / carbon dioxide ratio to 30% / 70%.

[0144] After slowly lowering the top-blowing lance to the molten steel surface, press the one-button injection button and slowly open the manual valve next to the furnace. Confirm that the top lance is igniting and that bubbles are rising to the surface of the molten steel. Then lower the top lance to a position 100-400mm from the furnace bottom, adjusting the opening according to the churning situation until it is fully open. After the injection is complete, blow argon gas for 5 minutes while simultaneously raising the top-blowing lance to its upper limit. After the argon purging is complete, measure the temperature, take a sample to determine the oxygen content, adjust the composition and temperature, tap the steel, and the process is complete.

[0145] Example 2

[0146] The initial oxygen content was 338.5 ppm, the initial nitrogen content was 224.2 ppm, the initial carbon content was 45.8 ppm, the molten steel temperature was 1602℃, and the loading amount was 150 kg.

[0147] Preliminary pipeline purging: Set the argon / hydrogen and argon / carbon dioxide ratios to 100 / 0, pressure to 0.2 MPa, and flow rate to 100 L / min. Open the furnace-side manual valve and press the one-button purging button. After purging for 2 minutes, close the furnace-side manual valve, and then close the one-button purging button.

[0148] Load the fuel, install the argon seal, power on and heat up. After a certain amount of molten pool forms at the bottom, set the bottom blowing mixture ratio to argon / carbon dioxide 100 / 0, flow rate to 5L / min, pressure to 0.1MPa, and blowing time to 30 minutes. Press the one-button blowing button and slowly open the furnace-side manual valve, adjusting the opening degree according to the churning situation until fully open. After all the fuel has melted, close the furnace-side manual valve and turn off the one-button blowing. Measure the temperature and oxygen content, and adjust the temperature to 1600℃±10℃.

[0149] Process parameters are set as follows: Argon and hydrogen pressure: 0.2 MPa; Argon and carbon dioxide pressure: 0.2 MPa; Mixed gas flow rate: 13 L / min; Injection time: 8 minutes; The mixing ratio is dynamically adjusted during the injection process. Initially, the argon / hydrogen ratio is 10% / 90%, and the argon / carbon dioxide ratio is 95% / 5%. After 3 minutes of injection, the argon / hydrogen ratio is adjusted to 30% / 70%, and the argon / carbon dioxide ratio to 70% / 30%. After 6 minutes of injection, the argon / hydrogen ratio is adjusted to 50% / 50%, and the argon / carbon dioxide ratio to 50% / 50%. After 7 minutes of injection, the argon / hydrogen ratio is adjusted to 70% / 30%, and the argon / carbon dioxide ratio to 30% / 70%.

[0150] After slowly lowering the top-blowing lance to the molten steel surface, press the one-button injection button and slowly open the manual valve next to the furnace. Confirm that the top lance is igniting and that bubbles are rising to the surface of the molten steel. Then lower the top lance to a position 100-400mm from the furnace bottom, adjusting the opening according to the churning situation until it is fully open. After the injection is complete, blow argon gas for 5 minutes while simultaneously raising the top-blowing lance to its upper limit. After the argon purging is complete, measure the temperature, take a sample to determine the oxygen content, adjust the composition and temperature, tap the steel, and the process is complete.

[0151] Example 3

[0152] The initial oxygen content was 285.4 ppm, the initial nitrogen content was 261.8 ppm, the initial carbon content was 52.5 ppm, the molten steel temperature was 1601℃, and the loading amount was 200 kg.

[0153] Preliminary pipeline purging: Set the argon / hydrogen and argon / carbon dioxide ratios to 100 / 0, pressure to 0.2 MPa, and flow rate to 100 L / min. Open the furnace-side manual valve and press the one-button purging button. After purging for 2 minutes, close the furnace-side manual valve, and then close the one-button purging button.

[0154] Load the fuel, install the argon seal, power on and heat up. After a certain amount of molten pool forms at the bottom, set the bottom blowing mixture ratio to argon / carbon dioxide 100 / 0, flow rate to 5L / min, pressure to 0.1MPa, and blowing time to 30 minutes. Press the one-button blowing button and slowly open the furnace-side manual valve, adjusting the opening degree according to the churning situation until fully open. After all the fuel has melted, close the furnace-side manual valve and turn off the one-button blowing. Measure the temperature and oxygen content, and adjust the temperature to 1600℃±10℃.

[0155] Process parameters are set as follows: Argon and hydrogen pressure: 0.2 MPa; Argon and carbon dioxide pressure: 0.2 MPa; Mixed gas flow rate: 16 L / min; Injection time: 8 minutes; The mixing ratio is dynamically adjusted during the injection process. Initially, the argon / hydrogen ratio is 10% / 90%, and the argon / carbon dioxide ratio is 95% / 5%. After 3 minutes of injection, the argon / hydrogen ratio is adjusted to 30% / 70%, and the argon / carbon dioxide ratio to 70% / 30%. After 6 minutes of injection, the argon / hydrogen ratio is adjusted to 50% / 50%, and the argon / carbon dioxide ratio to 50% / 50%. After 7 minutes of injection, the argon / hydrogen ratio is adjusted to 70% / 30%, and the argon / carbon dioxide ratio to 30% / 70%.

[0156] After slowly lowering the top-blowing lance to the molten steel surface, press the one-button injection button and slowly open the manual valve next to the furnace. Confirm that the top lance is igniting and that bubbles are rising to the surface of the molten steel. Then lower the top lance to a position 100-400mm from the furnace bottom, adjusting the opening according to the churning situation until it is fully open. After the injection is complete, blow argon gas for 5 minutes while simultaneously raising the top-blowing lance to its upper limit. After the argon purging is complete, measure the temperature, take a sample to determine the oxygen content, adjust the composition and temperature, tap the steel, and the process is complete.

[0157] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A top / bottom combined blowing system for a non-vacuum induction furnace, characterized in that: This includes hydrogen transport and regulation gas paths, carbon dioxide transport and regulation gas paths, argon transport and regulation gas paths, hydrogen-argon mixed transport and regulation gas paths, carbon dioxide-argon mixed transport and regulation gas paths, and control systems; The hydrogen delivery and regulating gas path is connected to the argon delivery and regulating gas path, and is further connected to the hydrogen-argon mixed delivery and regulating gas path, which is connected to the top-blown oxygen lance. The carbon dioxide delivery and regulating gas path is connected to the argon delivery and regulating gas path, and then connected to the carbon dioxide-argon mixed delivery and regulating gas path. The carbon dioxide-argon mixed delivery and regulating gas path is connected to the furnace bottom of the non-vacuum induction furnace. The control system is used to control the opening and closing of the hydrogen delivery and regulation gas path, the carbon dioxide delivery and regulation gas path, the argon delivery and regulation gas path, the hydrogen-argon mixed delivery and regulation gas path, and the carbon dioxide-argon mixed delivery and regulation gas path.

2. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 1, characterized in that: The hydrogen delivery and regulation circuit includes a hydrogen source and a first manual ball valve, a second manual ball valve, a first one-way check valve, a first fast electromagnetic shut-off valve, a first pressure transmitter, a first mass flow meter, a first flow regulating valve, and a first check valve that are sequentially connected to the hydrogen source. The second manual ball valve is equipped with a first pointer-type pressure gauge.

3. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 2, characterized in that: The carbon dioxide delivery and regulating gas path includes a carbon dioxide gas source and a third manual ball valve, a fourth manual ball valve, a second one-way check valve, a second fast electromagnetic shut-off valve, a second pressure transmitter, a second mass flow meter, a second flow regulating valve, and a second check valve that are sequentially connected to the carbon dioxide gas source. The fourth manual ball valve is equipped with a second pointer-type pressure gauge.

4. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 3, characterized in that: The argon gas delivery and regulation circuit includes an argon gas source, a fifth manual ball valve and a sixth manual ball valve connected in sequence to the argon gas source, and a top blowing circuit and a bottom blowing circuit connected to the sixth manual ball valve. The sixth manual ball valve is equipped with a third pointer-type pressure gauge.

5. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 4, characterized in that: The top-blowing air path includes a third fast electromagnetic shut-off valve, a third pressure transmitter, a third mass flow meter, a third flow regulating valve, and a third check valve connected in sequence.

6. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 5, characterized in that: The bottom blowing air path includes a fourth fast electromagnetic shut-off valve, a fourth pressure transmitter, a fourth mass flow meter, a fourth flow regulating valve, and a fourth check valve connected in sequence.

7. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 6, characterized in that: The hydrogen-argon mixed delivery and regulating gas path includes a hydrogen-argon mixing package connected to the first check valve and the third check valve, and a seventh manual ball valve, a fifth check valve, a fifth fast electromagnetic shut-off valve, an eighth manual ball valve and a first anti-backfire valve connected in sequence to the hydrogen-argon mixing package. The first backfire prevention valve is connected to the top-blown oxygen lance.

8. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 7, characterized in that: The carbon dioxide-argon gas mixing and regulating gas path includes a carbon dioxide-argon gas mixing package connected to the second check valve and the fourth check valve, and a ninth manual ball valve, a sixth check valve, a sixth fast electromagnetic shut-off valve, a tenth manual ball valve and a second backfire prevention valve connected in sequence to the carbon dioxide-argon gas mixing package. The second backfire prevention valve is connected to the bottom of the non-vacuum induction furnace via a bottom-blowing element.

9. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 7, characterized in that: The hydrogen-argon mixed gas delivery and regulating gas path is equipped with a compressed air delivery and regulating gas path; The compressed air delivery and regulating circuit includes a compressed air source, and an eleventh manual ball valve, a twelfth manual ball valve, a seventh fast electromagnetic shut-off valve, and a third one-way check valve that are sequentially connected to the compressed air source. The third one-way check valve is sequentially connected to the fifth fast electromagnetic shut-off valve, the eighth manual ball valve, and the first anti-backfire valve; The twelfth manual ball valve is equipped with a fourth pointer-type pressure gauge.

10. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 8, characterized in that: The carbon dioxide-argon gas mixing and regulating gas path is equipped with a compressed air conveying and regulating gas path; The compressed air delivery and regulating circuit includes a compressed air source, and an eleventh manual ball valve, a twelfth manual ball valve, a seventh fast electromagnetic shut-off valve, and a third one-way check valve that are sequentially connected to the compressed air source. The third one-way check valve is sequentially connected to the sixth fast electromagnetic shut-off valve, the tenth manual ball valve, and the second anti-backfire valve; The twelfth manual ball valve is equipped with a fourth pointer-type pressure gauge.

11. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 1, characterized in that: It also includes a gas leak detection alarm device for detecting gas leaks.

12. The furnace top / bottom combined blowing system for a non-vacuum induction furnace according to claim 1, characterized in that: It also includes top-blowing replacement / purge air paths and bottom-blowing replacement / purge air paths; The top-blown displacement / purge gas path is connected to the hydrogen delivery and regulating gas path and the argon delivery and regulating gas path; The bottom-blowing replacement / purge gas path is connected to the carbon dioxide delivery and regulating gas path and the argon delivery and regulating gas path.

13. A method for combined top / bottom blowing in a non-vacuum induction furnace, characterized in that, The following process is achieved using the top / bottom combined blowing system for a non-vacuum induction furnace as described in claim 8: The first manual ball valve, the second manual ball valve, the first one-way check valve, the first fast electromagnetic shut-off valve, the first pressure transmitter, the first mass flow meter, the first flow regulating valve, and the first check valve are opened in sequence to allow hydrogen to enter the hydrogen-argon mixture package. The third manual ball valve, the fourth manual ball valve, the second one-way check valve, the second fast electromagnetic shut-off valve, the second pressure transmitter, the second mass flow meter, the second flow regulating valve, and the second check valve are opened in sequence to allow carbon dioxide to enter the carbon dioxide-argon mixture package. Open the fifth manual ball valve and the sixth manual ball valve in sequence, as well as the top blowing gas path and the bottom blowing gas path, so that argon gas enters the hydrogen-argon mixture and the carbon dioxide-argon mixture respectively; The seventh manual ball valve, the fifth check valve, the fifth fast electromagnetic shut-off valve, the eighth manual ball valve, and the first anti-backfire valve are opened in sequence, so that the hydrogen-argon mixture in the hydrogen-argon mixture package is blown into the molten steel from the top of the non-vacuum induction furnace through the top-blown oxygen lance. The ninth manual ball valve, the sixth check valve, the sixth fast electromagnetic shut-off valve, the tenth manual ball valve, and the second anti-backfire valve are opened in sequence, so that the carbon dioxide-argon mixture in the carbon dioxide-argon mixture package is blown into the molten steel from the bottom of the non-vacuum induction furnace through the bottom blowing element.

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