Method for using converter gas for blast furnace iron production

Abstract

The application discloses a method for using converter gas for blast furnace iron-making production, and belongs to the technical field of steel smelting. In order to solve the problem that the discontinuity of using converter gas for blast furnace iron-making affects normal iron-making, the method comprises the following steps: the converter gas discharged from a converter (1) is alternately input into a first regenerative furnace (41) and a second regenerative furnace (42) to release heat, and the converter gas discharged from a gas storage device (6) is alternately input into the first regenerative furnace (41) and the second regenerative furnace (42) to absorb heat, so that high-temperature converter gas can be continuously and stably output to a blast furnace, and normal production of the blast furnace iron-making is ensured.

Description

Technical Field

[0001] This invention relates to the field of iron and steel smelting technology, specifically a method for using converter gas in blast furnace ironmaking. Background Technology

[0002] During the converter steelmaking process, carbon in the molten iron reacts chemically with the blown-in oxygen at high temperatures, producing a mixture of CO and CO2. Converter gas, a byproduct of converter steelmaking, not only has a very high temperature (1400℃-1500℃) but also a high CO content (45%-55%), making it highly valuable. The main components of converter gas are CO, CO2, O2, N2, and Ar, as well as dust carried by the gas, such as FeO, Fe2O3, CaO, and SiO2, with a total dust content of 80 g / Nm³. 3 -150g / Nm 3 If emitted directly into the atmosphere, it will not only pollute the environment but also lead to serious energy waste.

[0003] As a secondary energy source, converter gas is of paramount importance for energy conservation, emission reduction, and green development in my country's steel industry through its recovery and utilization. Traditional main uses of converter gas include: direct use in steelmaking, as boiler fuel, as fuel for rolling mill heating furnaces or lime kilns, blending with blast furnace gas for gas-fired power generation, and purification as a raw material for chemical production (pressure swing adsorption purification to produce CO, methanol, and ethanol). However, all these utilization methods suffer from low efficiency.

[0004] Traditional steelmaking processes utilize converter gas by cooling and dust removal before power generation. However, this process wastes a significant amount of sensible heat from the converter gas, resulting in low gas utilization (30%-40%) during power generation. Furthermore, direct combustion of the gas emits large amounts of carbon dioxide.

[0005] To recover and utilize converter gas, Chinese utility model patent CN215924990U, published on March 1, 2022, discloses a "Blast Furnace-Converter Steel Production System Based on Carbon Cycle." This system includes a gas injection device, a blast furnace, a converter, a converter gas collection device, and gas treatment equipment. Converter steelmaking is intermittent, meaning that recoverable converter gas cannot be continuously supplied to the blast furnace. The carbon cycle-based blast furnace-converter steel production system does not consider this intermittent nature. Intermittently injecting converter gas into the blast furnace would severely impact normal ironmaking operations. Summary of the Invention

[0006] To address the problem in the prior art where the intermittent use of converter gas in blast furnace ironmaking affects normal ironmaking production, this invention provides a method for using converter gas in blast furnace ironmaking. The converter gas discharged from the converter alternately enters a first regenerator and a second regenerator to release heat, while the converter gas discharged from the gas storage device alternately enters the first regenerator and the second regenerator to absorb heat. This ensures a continuous and stable supply of high-temperature converter gas to the blast furnace, guaranteeing normal blast furnace ironmaking production.

[0007] The technical solution adopted by the embodiments of the present invention to solve its technical problem is as follows:

[0008] A method for using converter gas in blast furnace ironmaking, wherein the method for processing converter gas in blast furnace ironmaking includes the following steps in sequence:

[0009] Step 1: A gas detection device detects the composition and content of the gas discharged from the converter to determine whether the gas meets the recovery conditions. If the gas does not meet the recovery conditions, it is dust-laden air; if it does meet the recovery conditions, it is converter gas. A first dust removal device removes dust from the dust-laden air. The converter gas enters the first regenerator of the regenerator group to release heat, and the first regenerator stores heat. The released heat from the regenerator enters a gas storage device for storage. The gas storage device discharges the converter gas into the second regenerator of the regenerator group to absorb heat, and the second regenerator releases heat. The absorbed heat from the second regenerator enters the blast furnace. A pressurization device pressurizes the converter gas discharged from the gas storage device.

[0010] Step 2: The gas detection device detects the composition and content of the gas discharged from the converter to determine whether the gas meets the recovery conditions. If the gas does not meet the recovery conditions, the gas discharged from the converter is dust-laden air; if it meets the recovery conditions, the gas discharged from the converter is converter gas. The first dust removal device removes dust from the dust-laden air. The converter gas enters the second regenerator of the regenerator group to release heat, and the second regenerator stores heat. The heated converter gas enters the gas storage device for storage. The gas storage device discharges the converter gas into the first regenerator of the regenerator group to absorb heat, and the first regenerator releases heat. The heated converter gas then enters the blast furnace. The pressurization device pressurizes the converter gas discharged from the gas storage device.

[0011] Step 3: Repeat steps 1 and 2 in sequence.

[0012] The beneficial effects of the embodiments of the present invention are:

[0013] 1. The method for using converter gas in blast furnace ironmaking includes a gas storage device, which can not only store the converted converter gas after heat release, but also continuously and stably output converter gas, ensuring the normal production of blast furnace ironmaking.

[0014] 2. It can efficiently store the heat of high-temperature, low-pressure dust-laden converter gas. After the converter gas is pressurized, most of the heat is returned to the converter gas, making it convenient to inject it into the blast furnace. The heat exchange efficiency reaches more than 90%.

[0015] 3. The technical solution of this invention can directly inject iron-containing dust from a large amount of converter gas into the blast furnace as a raw material for ironmaking, creating conditions for achieving zero solid waste emissions.

[0016] 4. High-reducing converter gas can be injected into the blast furnace to reduce the coke ratio. This not only makes full use of its large amount of sensible heat, but also has significant social benefits in reducing the coke ratio of blast furnace production and thus reducing carbon emissions from blast furnace production. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0018] Figure 1 This is a schematic diagram of the converter gas processing system described in this invention for use in blast furnace ironmaking.

[0019] Figure 2 This is a schematic diagram of a regenerative heat release furnace group.

[0020] Figure 3 This is a schematic diagram showing the first regenerator in a heat storage state and the second regenerator in a heat release state.

[0021] Figure 4 This is a schematic diagram showing the first regenerator in a heat release state and the second regenerator in a heat storage state.

[0022] Figure 5 This is a schematic diagram of a blast furnace.

[0023] Figure 6 This is a schematic diagram of the converter gas treatment system for blast furnace ironmaking production described in this invention, which utilizes other combustible gas sources.

[0024] The annotations in the attached figures are explained as follows:

[0025] 1. Converter; 2. Gas detection device; 3. First dust removal equipment; 4. Regenerative and exothermic furnace group; 5. Second dust removal equipment; 6. Gas storage device; 7. Purification and treatment equipment; 8. Pressurization device; 9. Blast furnace; 10. Combustible gas source;

[0026] 41. First regenerator; 42. Second regenerator;

[0027] 91. Tubular outlet; 92. Lower inlet of furnace body; 93. Furnace body; 94. Furnace waist; 95. Furnace belly; 96. Furnace cylinder. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] like Figures 1 to 2 As shown in the figure, the converter gas treatment system for blast furnace ironmaking production according to an embodiment of the present invention includes a gas detection device 2, a regenerative heat release furnace group 4, a gas storage device 6 and a pressurization device 8 connected in sequence by pipelines. The converter gas treatment system for blast furnace ironmaking production also includes a first dust removal device 3.

[0030] The gas detection device 2 can detect the composition and content of the gas discharged from the converter and determine whether the gas discharged from the converter meets the recovery conditions. If the gas discharged from the converter does not meet the recovery conditions, it is (low-temperature) dusty air. If the gas discharged from the converter meets the recovery conditions, it is (high-temperature) converter gas.

[0031] The first dust removal device 3 is capable of removing dust from the dust-laden air;

[0032] The heat storage and heat release furnace group 4 contains at least a first heat storage furnace 41 and a second heat storage furnace 42 arranged in parallel. The detected converter gas can enter the first heat storage furnace 41 or the second heat storage furnace 42 to release heat. Both the first heat storage furnace 41 and the second heat storage furnace 42 can store and release heat. The heat storage and heat release furnace group 4 may also contain more than three heat storage furnaces, which are connected in parallel or in parallel relationship.

[0033] The gas storage device 6 can store the converter gas after it has released heat. The gas storage device 6 can also supply the converter gas to the regenerative heat release furnace group 4. When the converter gas enters the first regenerative furnace 41 to release heat, the converter gas discharged from the gas storage device 6 can enter the second regenerative furnace 42 to absorb heat. When the converter gas enters the second regenerative furnace 42 to release heat, the converter gas discharged from the gas storage device 6 can enter the first regenerative furnace 41 to absorb heat. The converter gas after absorbing heat can enter the blast furnace.

[0034] The pressurizing device 8 can pressurize the converter gas discharged from the gas storage device 6.

[0035] In the converter gas treatment system for blast furnace ironmaking, the converter gas discharged from converter 1 alternately enters the first regenerator 41 and the second regenerator 42 to release heat, and the converter gas discharged from gas storage device 6 alternately enters the first regenerator 41 and the second regenerator 42 to absorb heat. The first regenerator 41 and the second regenerator 42 are alternately in a heat storage state and an heat release state, thereby ensuring a continuous and stable output of high-temperature converter gas to blast furnace 9 and guaranteeing normal ironmaking production.

[0036] In this embodiment, the inlet of the gas detection device 2 is connected to the converter 1. The gas detection device 2 mainly determines whether the gas meets the recovery conditions by detecting the O2 or CO content in the gas discharged from the converter. When the gas discharged from the converter does not meet the recovery conditions, the gas enters the first dust removal device 3, and is discharged into the air after dust removal. When the gas discharged from the converter meets the recovery conditions, the gas enters the regenerative heat recovery furnace group 4 for recycling.

[0037] The outlet of the gas detection device 2 can be connected to the inlet of the first dust removal device 3, the inlet of the first regenerator 41, or the inlet of the second regenerator 42. The first dust removal device 3 mainly processes low-temperature air with low dust content, and the first dust removal device 3 can adopt a coarse dust removal system such as a cyclone dust collector.

[0038] The production cycle of converter 1 is typically around 30 minutes, and the exhaust cycle of converter gas is typically around 12 minutes. The first regenerator 41 can be in a heat storage state, a heat preservation state, and a heat release state. The first regenerator 41 includes a heat storage inlet, a heat storage outlet, a heat release inlet, and a heat release outlet. When the converter gas enters the first regenerator 41 through its heat storage inlet and releases heat, and exits through its heat storage outlet, the first regenerator 41 is in a heat storage state. When the converter gas enters the first regenerator 41 through its heat release inlet and absorbs heat, and exits through its heat release outlet, the first regenerator 41 is in a heat release state. When the converter gas does not enter the first regenerator 41, the first regenerator 41 is in a heat preservation state.

[0039] The production cycle of converter 1 is typically around 30 minutes, and the exhaust cycle of converter gas is typically around 12 minutes. The second regenerator 42 can be in a heat storage state, a heat preservation state, and a heat release state. The second regenerator 42 also includes a heat storage inlet, a heat storage outlet, a heat release inlet, and a heat release outlet. When the converter gas enters the second regenerator 42 through its heat storage inlet and releases heat, and exits through its heat storage outlet, the second regenerator 42 is in a heat storage state. When the converter gas enters the second regenerator 42 through its heat release inlet and absorbs heat, and exits through its heat release outlet, the second regenerator 42 is in a heat release state. When the converter gas does not enter the second regenerator 42, the second regenerator 42 is in a heat preservation state.

[0040] like Figure 3 and Figure 4 As shown, when the first regenerator 41 is in a heat storage state, the second regenerator 42 is in a heat release state; when the second regenerator 42 is in a heat storage state, the first regenerator 41 is in a heat release state. When the first regenerator 41 is in a heat release state, the second regenerator 42 is in a heat storage state or a heat preservation state; when the second regenerator 42 is in a heat release state, the first regenerator 41 is in a heat storage state or a heat preservation state.

[0041] The heat storage inlet and heat release outlet of the first regenerator 41 can coincide, as can the heat storage outlet and heat release inlet of the first regenerator 41. The heat storage inlet and heat release outlet of the second regenerator 42 can coincide, as can the heat storage outlet and heat release inlet of the second regenerator 42. The heat storage inlet and heat release outlet of the first regenerator 41 are both located at the upper part of the first regenerator 41, and the heat storage outlet and heat release inlet of the first regenerator 41 are both located at the lower part of the first regenerator 41. The heat storage inlet and heat release outlet of the second regenerator 42 are also both located at the upper part of the second regenerator 42, and the heat storage outlet and heat release inlet of the second regenerator 42 are also both located at the lower part of the second regenerator 42.

[0042] Both the first regenerator 41 and the second regenerator 42 can be existing technologies, such as hot blast stoves. Both regenerators 41 and 42 contain a heat storage body, with the heat storage body in the center of both furnaces vertically. Each heat storage body contains vertically penetrating through-holes. During the heat release process of the converter gas entering the first regenerator 41 or the second regenerator 42, the gas passes through these through-holes, allowing the heat storage body to filter out iron-containing dust, thus performing coarse dust removal. Furthermore, during the heat release process of the converter gas entering the first regenerator 41 or the second regenerator 42, the gas can further carry away the iron-containing dust from the heat storage body, creating conditions for achieving zero solid waste emissions.

[0043] When the first regenerator 41 is in a heat release state, its heat release outlet is connected to the lower inlet 92 or tuyeres 91 of the blast furnace 9; when the second regenerator 42 is in a heat release state, its heat release outlet is connected to the lower inlet 92 or tuyeres 91 of the blast furnace 9, with the tuyeres 91 being lower than the lower inlet 92. Figure 5 As shown, the blast furnace 9 comprises, from top to bottom, a furnace body 93, a furnace waist 94, a furnace belly 95, and a hearth 96. Both the first regenerator 41 and the second regenerator 42 are equipped with heating devices. When the heat stored in the regenerator is insufficient to heat the converter gas to the required blast furnace temperature (850℃-950℃ if injected from the lower inlet 92, or 1150℃-1250℃ if injected from the tuyeres 91), the heating devices are activated to heat the regenerator, ensuring the converter gas reaches the required blast furnace temperature. If the recovered heat from the converter gas is insufficient to reach the required temperature, the regenerator can be supplemented by burning combustible gas. Combustible gas is not limited to blast furnace gas, converter gas, coke oven gas, or natural gas. When the regenerator receives high-temperature, low-pressure converter gas, a gravity or cyclone dust removal device can be installed within the regenerator to remove particulate matter from the converter gas to a certain extent.

[0044] The converter gas treatment system for blast furnace ironmaking also includes a second dust removal device 5, located between the regenerative heat release furnace group 4 and the gas storage device 6. The second dust removal device 5 removes dust from the converter gas after it has released heat in the regenerative heat release furnace group 4. The converter gas treated by the second dust removal device 5 can then enter the first regenerative furnace 41 or the second regenerative furnace 42 to absorb heat. For fine dust removal of the dust-laden converter gas, the second dust removal device 5 can use an electrostatic precipitator to ensure that the treated converter gas meets the requirements of the compressor.

[0045] The pressurizing device 8 can be located upstream or downstream of the regenerative heat exchanger group 4. Preferably, the pressurizing device 8 is located upstream of the regenerative heat exchanger group 4, that is, between the regenerative heat exchanger group 4 and the gas storage device 6. The gas storage device 6 is mainly used to store ambient temperature, low pressure, clean converter gas. A large gas holder can be selected to avoid the impact on normal blast furnace production caused by the direct use of intermittent converter gas. The volume of the gas storage device 6 can be determined according to project requirements, for example, the volume of the gas storage device 6 can be 30,000 cubic meters to 150,000 cubic meters. The pressurizing device 8 can pressurize the converter gas discharged from the gas storage device 6 and then enter the regenerative heat exchanger group 4 (the first regenerative furnace 41 or the second regenerative furnace 42). The converter gas absorbs heat in the first regenerative furnace 41 or the second regenerative furnace 42 and then enters the blast furnace 9 for use in blast furnace ironmaking. The function of the pressurizing device 8 is to make the pressure of the converter gas after heat absorption in the first regenerator 41 or the second regenerator 42 equal to the pressure inside the blast furnace 9, so as to ensure the normal production of blast furnace ironmaking.

[0046] The converter gas treatment system for blast furnace ironmaking also includes a purification and treatment device 7, located between the pressurization device 8 and the gas storage device 6. The purification and treatment device 7 treats the converter gas discharged from the gas storage device 6 to remove CO2, desulfurize, dehydrate, deoxygenate, and denitrify. The purification and treatment device 7 includes, but is not limited to, dust removal, pressurization, desulfurization, deoxygenation, dehydration, decarbonization, denitrification, and gas enrichment. The purification and treatment device 7 can utilize existing technology. In actual production, only certain treatment stages and devices can be used depending on the specific composition of the converter gas, or the order of the treatment stages and devices can be adjusted according to the specific treatment technologies used in each stage.

[0047] The following describes a method for using converter gas in blast furnace ironmaking. This method employs the aforementioned converter gas treatment system for blast furnace ironmaking and includes the following steps:

[0048] Step 1: Gas detection device 2 detects the composition and content of the converter exhaust gas to determine whether the converter exhaust gas meets the recovery conditions. Gas that does not meet the recovery conditions is dust-laden air; gas that meets the recovery conditions is converter gas. First dust removal device 3 removes dust from the dust-laden air. The converter gas can enter the first regenerator 41 of the regenerator group 4 to release heat, and the first regenerator 41 stores heat (i.e., is in a heat storage state). The released converter gas enters the gas storage device 6 for storage. The gas storage device 6 discharges the converter gas into the second regenerator 42 of the regenerator group 4 to absorb heat, and the second regenerator 42 releases heat (i.e., is in a heat release state). Pressurization device 8 pressurizes the converter gas discharged from the gas storage device 6, such as... Figure 3 As shown;

[0049] Step 2: Gas detection device 2 detects the composition and content of the converter exhaust gas to determine whether the converter exhaust gas meets the recovery conditions. Gas that does not meet the recovery conditions is dust-laden air; gas that meets the recovery conditions is converter gas. First dust removal device 3 removes dust from the dust-laden air. The converter gas can enter the second regenerator 42 of the regenerator group 4 to release heat, and the second regenerator 42 stores heat (i.e., is in a heat storage state). The released converter gas enters the gas storage device 6 for storage. The gas storage device 6 discharges the converter gas into the first regenerator 41 of the regenerator group 4 to absorb heat, and the first regenerator 41 releases heat (i.e., is in a heat release state). Pressurization device 8 pressurizes the converter gas discharged from the gas storage device 6, such as... Figure 4 As shown;

[0050] Step 3: Repeat steps 1 and 2 in sequence.

[0051] In steps 1 and 2, the gas detection device 2 primarily determines whether the gas meets the recovery conditions by detecting the O2 or CO content in the converter exhaust gas. When the converter exhaust gas does not meet the recovery conditions, it enters the first dust removal device 3, where it is discharged into the air after dust removal and is not recycled. When the converter exhaust gas meets the recovery conditions, it enters the regenerative heat recovery furnace group 4 for recycling.

[0052] For example, if gas detection device 2 detects that the O2 content in the gas is >1% or the CO content is <10%, it indicates that the oxidation reaction between O2 and the high-temperature molten iron in converter 1 is basically complete, and the gas discharged from the converter does not meet the recovery conditions. At this time, the CO content in the discharged gas is very low and has no recovery value, and its emission into the air will not cause significant air pollution. If gas detection device 2 detects that the O2 content in the gas is ≤1% or the CO content is ≥10%, the gas discharged from the converter meets the recovery conditions.

[0053] In steps 1 and 2, when the converter exhaust gas does not meet the recovery conditions, the inlet end of the first dust removal device 3 is connected to the converter 1, while the first regenerator 41 and the second regenerator 42 are not connected to the converter 1. The converter exhaust gas then enters the first dust removal device 3, but not the first regenerator 41 or the second regenerator 42. When the converter exhaust gas meets the recovery conditions, the first regenerator 41 or the second regenerator 42 is connected to the converter 1, while the first dust removal device 3 is not connected to the converter 1. The converter exhaust gas then enters the first regenerator 41 or the second regenerator 42, but not the first dust removal device 3.

[0054] In step 1, when the converter gas enters the first regenerator 41 from the regenerator inlet and releases heat, and exits from the regenerator outlet, the first regenerator 41 stores heat; when the converter gas does not enter the first regenerator 41, the first regenerator 41 is in a heat preservation state; when the converter gas enters the second regenerator 42 from the heat release inlet and absorbs heat, and exits from the heat release outlet, the second regenerator 42 releases heat, and the converter gas enters the blast furnace 9 after absorbing heat from the second regenerator 42.

[0055] In step 1, when the converter gas (1400℃-1500℃) enters the first regenerator 41 through its heat inlet and releases heat, and exits through its heat outlet, the heat storage body within the first regenerator 41 stores heat. This heat storage body can filter out iron-containing dust from the converter gas. The converter gas releases heat, and the temperature of the released converter gas is 100℃-150℃, and the pressure is 4KPa-6KPa. When the converter gas enters the second regenerator 42 through its heat release inlet and absorbs heat, and exits through its heat release outlet, the heat storage body within the second regenerator 42 releases heat. The converter gas can then carry away the iron-containing dust from the heat storage body and send it into the blast furnace 9.

[0056] In step 2, when the converter gas enters the second regenerator 42 from the regenerator inlet and releases heat, and exits from the regenerator outlet, the second regenerator 42 stores heat; when the converter gas does not enter the second regenerator 42, the second regenerator 42 is in a heat preservation state; when the converter gas enters the first regenerator 41 from the heat release inlet and absorbs heat, and exits from the heat release outlet, the first regenerator 41 releases heat, and the converter gas enters the blast furnace 9 after absorbing heat from the first regenerator 41.

[0057] In step 2, when the converter gas (1400℃-1500℃) enters the second regenerator 42 through its heat inlet and releases heat, and exits through its heat outlet, the heat storage body within the second regenerator 42 stores heat. This heat storage body can filter out iron-containing dust from the converter gas. The converter gas releases heat, and the temperature of the released converter gas is 100℃-150℃, and the pressure is 4KPa-6KPa. When the converter gas enters the first regenerator 41 through its heat release inlet and absorbs heat, and exits through its heat release outlet, the heat storage body within the first regenerator 41 releases heat. The converter gas can then carry away the iron-containing dust from the heat storage body and send it into the blast furnace 9.

[0058] In step 1, when the heat stored in the regenerator in the second regenerator 42 is insufficient to heat the converter gas to the temperature required by the blast furnace 9 (if the temperature is 850℃-950℃ if injected from the lower inlet 92 of the furnace body, or 1150℃-1250℃ if injected from the tuyeres 91), the heating device in the second regenerator 42 is activated to heat the regenerator in the second regenerator 42.

[0059] In step 2, when the heat stored in the heat storage body in the first heat storage furnace 41 is insufficient to heat the converter gas to the temperature required by the blast furnace 9 (if the temperature is 850℃-950℃ if it is injected from the lower inlet 9 of the furnace body, or 1150℃-1250℃ if it is injected from the tuyeres 91), the heating device in the first heat storage furnace 41 is activated to heat the heat storage body in the first heat storage furnace 41.

[0060] In steps 1 and 2, a second dust removal device 5 is used to perform fine dust removal treatment on the converter gas after heat release in the regenerative heat exchanger group 4. After fine dust removal treatment, clean converter gas with a dust content of less than 10 mg / m³ is obtained at room temperature (approximately 70°C) and low pressure (3KPa-4KPa). 3 After the fine dust removal treatment, the converter gas enters the gas storage device 6 for storage.

[0061] In steps 1 and 2, the converter gas discharged from the gas storage device 6 is treated with purification equipment 7 to remove CO2, desulfurize, dehydrate, deoxygenate and denitrify.

[0062] In steps 1 and 2, the pressurizing device 8 pressurizes the converter gas discharged from the gas storage device 6 before it enters the regenerative heat exchanger group 4. Preferably, the pressurizing device 8 pressurizes the converter gas discharged from the purification and treatment equipment 7 before it enters the regenerative heat exchanger group 4. The pressure of the pressurized converter gas is made greater than the pressure inside the blast furnace 9, for example, at least 0.1 MPa higher than the pressure inside the blast furnace 9, to ensure normal production of blast furnace ironmaking.

[0063] The pressurizing device 8 can not only pressurize the converter gas discharged from the gas storage device 6 before it enters the regenerative heat release furnace group 4, but also pressurize other combustible gas sources 10. The outlet end of the combustible gas source 10 is connected to the inlet end of the pressurizing device 8. The combustible gas source 10 may contain decarbonized blast furnace gas, purified and reformed natural gas, or coke oven gas, such as... Figure 6 As shown.

[0064] The following is a brief introduction to the specific process of using converter gas in blast furnace ironmaking, taking the production cycle of converter 1 as usually around 30 minutes and the emission cycle of converter gas as usually around 12 minutes as an example.

[0065] 0 minutes - 12 minutes:

[0066] Converter 1 discharges gas, and gas detection device 2 detects that the discharged gas meets the recovery conditions. The discharged gas (converter gas) enters the first regenerator 41 of the regenerator group 4 for heat release. The discharged gas then enters the second dust removal device 5 for fine dust removal. The finely dust-removed gas then enters the gas storage device 6 for storage. The gas storage device 6 discharges the gas into the purification treatment device 7 for further purification. The purified gas then enters the pressurizing device 8 for pressurization. The pressurized gas then enters the second regenerator 42 of the regenerator group 4 for heat absorption. The heat-absorbed gas then enters the blast furnace 9.

[0067] 12-30 minutes:

[0068] The gas discharged from converter 1 does not meet the recovery conditions if the gas detection device 2 detects that the gas discharged from converter 1 does not meet the recovery conditions. The gas discharged from converter 1 (dust-containing air) enters the first dust removal device 3 for dust removal and is then discharged into the air. The gas discharged from converter 1 (dust-containing air) does not enter the regenerative heat exchange furnace group 4. The gas storage device 6 discharges the converter gas into the purification treatment device 7 for purification. The purified converter gas enters the pressurization device 8 for pressurization. The pressurized converter gas enters the second regenerative furnace 42 of the regenerative heat exchange furnace group 4 for heat absorption. The heat-absorbed converter gas enters the blast furnace 9.

[0069] 30-42 minutes:

[0070] Gas is discharged from converter 1. Gas detection device 2 detects that the discharged gas from converter meets the recovery conditions. The discharged gas (converter gas) from converter 1 enters the second regenerator 42 of the regenerator group 4 for heat release. The discharged gas then enters the second dust removal device 5 for fine dust removal. The finely dust-removed gas then enters the gas storage device 6 for storage. The gas storage device 6 discharges the gas into the purification treatment device 7 for further purification. The purified gas then enters the pressurizing device 8 for pressurization. The pressurized gas then enters the first regenerator 41 of the regenerator group 4 for heat absorption. The heat-absorbed gas then enters the blast furnace 9.

[0071] 42-60 minutes:

[0072] Gas is discharged from converter 1. Gas detection device 2 detects that the gas discharged from converter 1 does not meet the recovery conditions. The gas discharged from converter 1 (dust-containing air) enters the first dust removal device 3 for dust removal and is then discharged into the air. The gas discharged from converter 1 (dust-containing air) does not enter the regenerative heat exchange furnace group 4. The gas storage device 6 discharges the converter gas into the purification treatment device 7 for purification. The purified converter gas enters the pressurization device 8 for pressurization. The pressurized converter gas enters the first regenerative furnace 41 of the regenerative heat exchange furnace group 4 for heat absorption. The heat-absorbed converter gas enters the blast furnace 9.

[0073] Repeat the process from 0 minutes to 60 minutes continuously.

[0074] This invention first analyzes the composition of the gas discharged from the converter steelmaking process, and then performs pre-injection treatment before the blast furnace, which can significantly improve the efficiency of the treatment system.

[0075] This invention can be equipped with a regenerator system, which can efficiently store the heat of high-temperature, low-pressure dust-containing converter gas. After the converter gas is pressurized, most of the heat is returned to the converter gas, making it convenient to inject it into the blast furnace.

[0076] In this invention, when the regenerator is in the "heat storage" state, it has a certain coarse dust removal function for high-temperature and low-pressure converter gas, creating favorable conditions for improving the efficiency of subsequent fine dust removal.

[0077] When the regenerator is in the "heat release" state, the low-temperature high-pressure converter gas is heated and the iron-containing dust trapped during the "heat storage" process is also carried away, creating conditions for achieving zero solid waste discharge.

[0078] The regenerator system mentioned in the technical solution of this invention makes full use of the periodicity of converter gas generated in converter steelmaking to achieve a reasonable decomposition of "heat storage" and "heat release" without affecting the normal production of blast furnace ironmaking.

[0079] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, substitutions of equivalent components, or equivalent changes and modifications made within the scope of protection of the present invention, should still fall within the scope of the present invention. Furthermore, the technical features, technical solutions, and embodiments of the present invention can be freely combined and used.

Claims

1. A method for using converter gas in blast furnace ironmaking, characterized in that, The method for using converter gas in blast furnace ironmaking production includes the following steps in sequence: Step 1: The gas detection device (2) detects the composition and content of the gas discharged from the converter and determines whether the gas discharged from the converter meets the recovery conditions. If the gas discharged from the converter does not meet the recovery conditions, it is dusty air; if the gas discharged from the converter meets the recovery conditions, it is converter gas. The first dust removal device (3) removes dust from the dusty air. The converter gas enters the first regenerator (41) of the regenerator group (4) to release heat, and the first regenerator (41) stores heat. The converted gas after heat release enters the gas storage device (6) for storage. The gas storage device (6) discharges the converted gas into the second regenerator (42) of the regenerator group (4) to absorb heat. The second regenerator (42) releases heat, and the converted gas after heat absorption enters the blast furnace (9). The pressurizing device (8) pressurizes the converted gas discharged from the gas storage device (6). Step 2: The gas detection device (2) detects the composition and content of the gas discharged from the converter and determines whether the gas discharged from the converter meets the recovery conditions. If the gas discharged from the converter does not meet the recovery conditions, it is dusty air; if the gas discharged from the converter meets the recovery conditions, it is converter gas. The first dust removal device (3) removes dust from the dusty air. The converter gas enters the second regenerator (42) of the regenerator group (4) to release heat, and the second regenerator (42) stores heat. The converted gas after heat release enters the gas storage device (6) for storage. The gas storage device (6) discharges the converted gas into the first regenerator (41) of the regenerator group (4) to absorb heat. The first regenerator (41) releases heat, and the converted gas after heat absorption enters the blast furnace (9). The pressurizing device (8) pressurizes the converted gas discharged from the gas storage device (6). Step 3: Repeat steps 1 and 2 in sequence; In steps 1 and 2, the gas detection device (2) determines whether the gas meets the recycling conditions by detecting the content of O2 or CO in the gas discharged from the converter; when the gas discharged from the converter does not meet the recycling conditions, the gas discharged from the converter enters the first dust removal device (3) for dust removal and is then discharged into the air; when the gas discharged from the converter meets the recycling conditions, the gas discharged from the converter enters the regenerative heat release furnace group (4) for recycling. In step 1, when the converter gas enters the first regenerator (41) to release heat, the heat storage body in the first regenerator (41) stores heat and filters out the iron-containing dust in the converter gas. When the converter gas enters the second regenerator (42) to absorb heat, the converter gas carries away the iron-containing dust in the heat storage body in the second regenerator (42) and sends it into the blast furnace (9). In step 2, when the converter gas enters the second regenerator (42) to release heat, the heat storage body in the second regenerator (42) stores heat and filters out the iron-containing dust in the converter gas. When the converter gas enters the first regenerator (41) to absorb heat, the converter gas carries away the iron-containing dust in the heat storage body in the first regenerator (41) and sends it into the blast furnace (9).

2. The method for using converter gas in blast furnace ironmaking according to claim 1, characterized in that, In steps 1 and 2, when the gas detection device (2) detects that the O2 content in the converter exhaust gas is >1% or the CO content is <10%, the converter exhaust gas does not meet the recovery conditions; when the gas detection device (2) detects that the O2 content in the converter exhaust gas is ≤1% or the CO content is ≥10%, the converter exhaust gas meets the recovery conditions.

3. The method for using converter gas in blast furnace ironmaking according to claim 1, characterized in that, In steps 1 and 2, when the gas discharged from the converter meets the recovery conditions, the first regenerator (41) or the second regenerator (42) is connected to the converter (1), and the first dust removal device (3) is not connected to the converter (1). The gas discharged from the converter enters the first regenerator (41) or the second regenerator (42) instead of the first dust removal device (3).

4. The method for using converter gas in blast furnace ironmaking according to claim 1, characterized in that, In step 1, when the heat stored in the regenerator in the second regenerator (42) is insufficient to heat the converter gas to the temperature required by the blast furnace (9), the heating device in the second regenerator (42) is activated to heat the regenerator in the second regenerator (42).

5. The method for using converter gas in blast furnace ironmaking according to claim 1, characterized in that, In step 2, when the heat stored in the heat storage body in the first heat storage furnace (41) is insufficient to heat the converter gas to the temperature required by the blast furnace (9), the heating device in the first heat storage furnace (41) is activated to heat the heat storage body in the first heat storage furnace (41).

6. The method for using converter gas in blast furnace ironmaking according to claim 1, characterized in that, In steps 1 and 2, a second dust removal device (5) is used to perform fine dust removal on the converter gas after it has been heated in the regenerative heat release furnace group (4). After the fine dust removal, the converter gas enters the gas storage device (6) for storage.

7. The method for using converter gas in blast furnace ironmaking according to claim 1, characterized in that, In steps 1 and 2, the purification and treatment equipment (7) is used to remove CO2, desulfurize, dehydrate, deoxygenate and denitrify the converter gas discharged from the gas storage device (6), and the pressurization device (8) pressurizes the converter gas discharged from the purification and treatment equipment (7) before it enters the regenerative heat release furnace group (4).

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