Treatment system and method for converter gas for ironmaking in blast furnace

Abstract

A treatment system and treatment method for a converter gas for ironmaking in a blast furnace (9), which belong to the technical field of iron and steel smelting. The treatment system for a converter gas for ironmaking in a blast furnace (9) comprises a gas detection device (2), a heat storage and release furnace group (4), a gas storage device (6) and a pressurizing device (8), which are sequentially connected by a gas transmission line, and the treatment system for a converter gas for ironmaking in a blast furnace (9) further comprises a first dust removal apparatus (3). The treatment system for a converter gas for ironmaking in a blast furnace (9) comprising the gas storage device (6) can not only store the converter gas after heat release, but can also output the converter gas continuously and stably, thereby ensuring normal ironmaking in the blast furnace (9).

Description

Processing system and method for converter gas used in blast furnace ironmaking production

[0001] Related applications

[0002] This invention claims priority to the Chinese invention patent application with application number 202311577644.2, application date November 24, 2023, and invention name "Method for using converter gas for blast furnace ironmaking production", and quotes the contents disclosed in the above patent application as part of this application. Technical Field

[0003] The present invention relates to the technical field of steel smelting, and in particular to a system for processing converter gas for blast furnace ironmaking production, and a method for processing converter gas for blast furnace ironmaking production. Background Art

[0004] During the converter steelmaking process, the carbon in the molten iron reacts chemically with the oxygen blown in at high temperatures, generating a mixed gas of CO and CO2. Converter gas, a by-product of converter steelmaking, not only has a very high temperature (1400-1500°C), but also has a high CO content (45%-55%), making it highly valuable for utilization. The main components of converter gas are CO, CO2, O2, N2, Ar, and FeO, Fe2O3, CaO, SiO2, and other dust carried by the gas. The total dust content is 80g / Nm 3 -150g / Nm 3 , if discharged directly into the atmosphere, it will not only pollute the environment, but also lead to serious waste of energy.

[0005] As a secondary energy source, the recovery and utilization of converter gas is crucial for energy conservation, consumption reduction, and green development in steel companies. Traditionally, converter gas has been used directly in steelmaking, as a boiler fuel, in steel rolling mill heating furnaces and lime kilns, blended with blast furnace gas for gas-fired power generation, and purified as a raw material for chemical product production (such as CO, methanol, and ethanol through pressure swing adsorption purification). However, these utilization methods all suffer from low efficiency.

[0006] The traditional process of steel enterprises is to utilize converter gas by cooling and dust removal before power generation. In this process, a large amount of sensible heat of the converter gas is wasted, the utilization rate of the gas in the power generation process is low (30%-40%), and direct combustion will emit a large amount of carbon dioxide.

[0007] To recycle 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 carbon cycle-based blast furnace-converter steel production system includes a gas injection device, a blast furnace, a converter, a converter gas collection device, and gas treatment equipment. Converter steelmaking is intermittent, and this characteristic dictates that recyclable converter gas cannot be continuously supplied to the blast furnace. This carbon cycle-based blast furnace-converter steel production system fails to account for the intermittent nature of converter gas. If converter gas is intermittently injected into the blast furnace, it will seriously impact normal ironmaking in the blast furnace.

[0008] Application Contents

[0009] In order to solve the problem in the above-mentioned prior art that the use of converter gas for blast furnace ironmaking affects normal ironmaking due to intermittent use, the present invention provides a processing system and method for converter gas for blast furnace ironmaking production. The converter gas discharged from the converter alternately enters the first heat storage furnace and the second heat storage furnace to release heat, and the converter gas discharged from the gas storage device alternately enters the first heat storage furnace and the second heat storage furnace to absorb heat, thereby being able to continuously and stably output high-temperature converter gas to the blast furnace, ensuring the normal production of blast furnace ironmaking.

[0010] The technical solution adopted by the embodiment of the present invention to solve the technical problem is:

[0011] A converter gas processing system for blast furnace ironmaking production includes a gas detection device, a heat storage and heat release furnace group, a gas storage device, and a pressurizing device connected in sequence via a gas transmission pipeline. The converter gas processing system for blast furnace ironmaking production also includes a first dust removal device;

[0012] The gas detection device can detect the composition and content of the converter exhaust gas, and judge whether the converter exhaust gas meets the recovery conditions. If the converter exhaust gas does not meet the recovery conditions, it is dusty air; if the converter exhaust gas meets the recovery conditions, it is converter gas.

[0013] The first dust removal device is capable of performing dust removal on the dust-laden air;

[0014] The heat storage and release furnace group includes a first heat storage furnace and a second heat storage furnace. The converter gas can enter the first heat storage furnace or the second heat storage furnace to release heat. The first heat storage furnace and the second heat storage furnace can both store and release heat.

[0015] The gas storage device can store the converter gas after heat release, and can also transport the converter gas to the heat storage and heat release furnace group. When the converter gas enters the first heat storage furnace to release heat, the converter gas discharged from the gas storage device can enter the second heat storage furnace to absorb heat; when the converter gas enters the second heat storage furnace to release heat, the converter gas discharged from the gas storage device can enter the first heat storage furnace to absorb heat; the converter gas after heat absorption can enter the blast furnace;

[0016] The pressurizing device can pressurize the converter gas discharged from the gas storage device.

[0017] A method for processing converter gas for blast furnace ironmaking production, the method comprising the following steps in sequence:

[0018] Step 1: A gas detection device detects the composition and content of converter exhaust gas to determine whether the converter exhaust gas meets the recovery conditions. The converter exhaust gas that does not meet the recovery conditions is dust-laden air, and the converter exhaust gas that meets the recovery conditions is converter gas. A first dust removal device removes dust from the dust-laden air. The converter gas enters the first regenerative furnace of the regenerative furnace group to release heat, and the first regenerative furnace stores heat. The converter gas after heat release enters a gas storage device for storage. The gas storage device discharges the converter gas into the second regenerative furnace of the regenerative furnace group to absorb heat. The second regenerative furnace releases heat, and the converter gas after heat absorption enters a blast furnace. A pressurizing device pressurizes the converter gas discharged from the gas storage device.

[0019] Step 2: The gas detection device detects the composition and content of the converter exhaust gas to determine whether the converter exhaust gas meets the recovery conditions. The converter exhaust gas that does not meet the recovery conditions is dust-laden air, and the converter exhaust gas that meets the recovery conditions is converter gas. The first dust removal device removes dust from the dust-laden air. The converter gas enters the second regenerative furnace of the regenerative furnace group to release heat, and the second regenerative furnace stores heat. The converter gas after heat release enters the gas storage device for storage. The gas storage device discharges the converter gas into the first regenerative furnace of the regenerative furnace group to absorb heat. The first regenerative furnace releases heat, and the converter gas after heat absorption enters the blast furnace. The pressurizing device pressurizes the converter gas discharged from the gas storage device.

[0020] Step 3. Repeat steps 1 and 2 in sequence.

[0021] The beneficial effects of the embodiments of the present invention are:

[0022] 1. The converter gas processing system for blast furnace ironmaking production contains a gas storage device, which can not only store the converter gas after heat release, but also continuously and stably output the converter gas, ensuring the normal production of blast furnace ironmaking.

[0023] 2. It can efficiently store the heat of high-temperature, low-pressure, dusty 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, with a heat exchange efficiency of more than 90%.

[0024] 3. The technical solution of the present invention can directly inject a large amount of iron-containing dust in the converter gas into the blast furnace as ironmaking raw material, creating conditions for achieving zero solid waste emissions.

[0025] 4. Highly reducing converter gas can be injected into the blast furnace to reduce the coke ratio, which 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. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0027] FIG1 is a schematic diagram of a system for processing converter gas for blast furnace ironmaking production according to the present invention.

[0028] FIG2 is a schematic diagram of a heat storage and heat release furnace group.

[0029] FIG3 is a schematic diagram showing that the first heat storage furnace is in a heat storage state and the second heat storage furnace is in a heat release state.

[0030] FIG4 is a schematic diagram showing that the first heat storage furnace is in a heat releasing state and the second heat storage furnace is in a heat storing state.

[0031] FIG5 is a schematic diagram of a blast furnace.

[0032] FIG6 is a schematic diagram of a system for processing converter gas for blast furnace ironmaking production according to the present invention utilizing other combustible gas sources.

[0033] The following are the descriptions of the reference numerals:

[0034] 1. Converter; 2. Gas detection device; 3. First dust removal equipment; 4. Thermal storage and release furnace group; 5. Second dust removal equipment; 6. Gas storage device; 7. Purification and purification equipment; 8. Pressurization device; 9. Blast furnace; 10. Combustible gas source;

[0035] 41. First regenerative furnace; 42. Second regenerative furnace;

[0036] 91. Tuyere; 92. Lower entrance of furnace body; 93. Furnace body; 94. Furnace waist; 95. Furnace belly; 96. Furnace hearth. DETAILED DESCRIPTION

[0037] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0038] As shown in Figures 1 and 2, a system for processing converter gas for blast furnace ironmaking according to an embodiment of the present invention includes a gas detection device 2, a heat storage and release furnace group 4, a gas storage device 6, and a pressurizing device 8 connected in sequence by pipelines. The system for processing converter gas for blast furnace ironmaking also includes a first dust removal device 3;

[0039] The gas detection device 2 can detect the composition and content of the converter exhaust gas and determine whether the converter exhaust gas meets the recovery conditions. If the converter exhaust gas does not meet the recovery conditions, it is (low-temperature) dust-laden air. If the converter exhaust gas meets the recovery conditions, it is (high-temperature) converter gas.

[0040] The first dust removal device 3 is capable of performing dust removal on the dust-laden air;

[0041] The heat storage and release furnace group 4 includes at least a first heat storage furnace 41 and a second heat storage furnace 42 arranged in parallel. The converter gas after detection can enter the first heat storage furnace 41 or the second heat storage furnace 42 to release heat. The first heat storage furnace 41 and the second heat storage furnace 42 can both store and release heat. The heat storage and release furnace group 4 can also include more than three heat storage furnaces, and the heat storage furnaces are connected in parallel or in parallel.

[0042] The gas storage device 6 can store the converter gas after heat release, and can also transport the converter gas to the heat storage and 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; after absorbing heat, the converter gas can enter the blast furnace;

[0043] The pressurizing device 8 can pressurize the converter gas discharged from the gas storage device 6 .

[0044] In the processing system for converter gas used in blast furnace ironmaking production, the converter gas discharged from the converter 1 alternately enters the first regenerator 41 and the second regenerator 42 to release heat, and the converter gas discharged from the 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 the first regenerator 41 and the second regenerator 42 are alternately in a heat release state, thereby ensuring that the high-temperature converter gas is continuously and stably output from the blast furnace 9, thereby ensuring normal ironmaking production.

[0045] In this embodiment, the inlet of gas detection device 2 is connected to converter 1. Gas detection device 2 primarily detects the O2 or CO content in the converter exhaust gas to determine whether it meets recovery conditions. If the converter exhaust gas does not meet recovery conditions, it enters first dust removal equipment 3 for dust removal and discharge into the air. If it meets recovery conditions, it enters thermal storage and release furnace group 4 for recycling.

[0046] 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 regenerative furnace 41, or the inlet of the second regenerative furnace 42. The first dust removal device 3 mainly processes low-dust, low-temperature air. The first dust removal device 3 can use a coarse dust removal system such as a cyclone dust collector.

[0047] The production cycle of the converter 1 is usually about 30 minutes, and the discharge cycle of the converter gas is usually about 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 has 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 from the heat storage inlet to release heat and is discharged from the heat storage outlet of the first regenerator 41, the first regenerator 41 is in a heat storage state; when the converter gas enters the first regenerator 41 from the heat release inlet to absorb heat and is discharged from the heat release outlet of the first regenerator 41, 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.

[0048] The production cycle of the converter 1 is generally about 30 minutes, and the discharge cycle of the converter gas is generally about 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 has 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 from the heat storage inlet to release heat and is discharged from the heat storage outlet of the second regenerator 42, the second regenerator 42 is in a heat storage state; when the converter gas enters the second regenerator 42 from the heat release inlet to absorb heat and is discharged from the heat release outlet of the second regenerator 42, 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.

[0049] As shown in Figures 3 and 4, when the first regenerative furnace 41 is in the heat storage state, the second regenerative furnace 42 is in the heat release state; when the second regenerative furnace 42 is in the heat storage state, the first regenerative furnace 41 is in the heat release state. When the first regenerative furnace 41 is in the heat release state, the second regenerative furnace 42 is in the heat storage state or the heat preservation state; when the second regenerative furnace 42 is in the heat release state, the first regenerative furnace 41 is in the heat storage state or the heat preservation state.

[0050] The heat storage inlet and heat release outlet of the first regenerative furnace 41 can overlap, the heat storage outlet and heat release inlet of the first regenerative furnace 41 can overlap, the heat storage inlet and heat release outlet of the second regenerative furnace 42 can overlap, and the heat storage outlet and heat release inlet of the second regenerative furnace 42 can overlap. The heat storage inlet and heat release outlet of the first regenerative furnace 41 are both located at the top of the first regenerative furnace 41, the heat storage outlet and heat release inlet of the first regenerative furnace 41 are both located at the bottom of the first regenerative furnace 41, the heat storage inlet and heat release outlet of the second regenerative furnace 42 are also both located at the top of the second regenerative furnace 42, and the heat storage outlet and heat release inlet of the second regenerative furnace 42 are also both located at the bottom of the second regenerative furnace 42.

[0051] The first heat storage furnace 41 and the second heat storage furnace 42 can both adopt existing technology products, such as hot blast furnaces. A heat storage body is provided in the first heat storage furnace 41 and the second heat storage furnace 42. In the vertical direction, the heat storage body in the first heat storage furnace 41 is located in the middle, and the heat storage body in the second heat storage furnace 42 is also located in the middle. The heat storage body contains a through hole that runs through in the vertical direction. When the converter gas enters the first heat storage furnace 41 or the second heat storage furnace 42 to release heat, the converter gas passes through the through hole. The heat storage body can filter out the iron-containing dust in the converter gas and perform rough dust removal on the converter gas. When the converter gas enters the first heat storage furnace 41 or the second heat storage furnace 42 to release heat, the converter gas can take away the iron-containing dust in the heat storage body, creating conditions for achieving zero solid waste emissions.

[0052] When the first regenerator 41 is releasing heat, the heat release outlet of the first regenerator 41 communicates with the lower shaft inlet 92 or tuyere 91 of the blast furnace 9. When the second regenerator 42 is releasing heat, the heat release outlet of the second regenerator 42 communicates with the lower shaft inlet 92 or tuyere 91 of the blast furnace 9. The tuyere 91 is lower than the lower shaft inlet 92, as shown in FIG5 . The blast furnace 9 comprises a shaft 93, a waist 94, a belly 95, and a hearth 96, arranged in order from top to bottom. 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°C-950°C if injected from the lower shaft inlet 92, 1150°C-1250°C if injected from the tuyere 91), the heating devices are activated to heat the regenerator to ensure that the converter gas reaches the required blast furnace temperature. If the recovered converter gas heat isn't sufficient to reach the required temperature, the regenerator can be supplemented with heat by burning combustible gases. Combustible gases include, but are not limited to, blast furnace gas, converter gas, coke oven gas, and natural gas. When the regenerator receives high-temperature, low-pressure converter gas, it can utilize the space within the regenerator to install a coarse dust removal device, such as gravity or cyclone, to remove particulate matter from the converter gas to a certain extent.

[0053] The converter gas processing system for blast furnace ironmaking also includes a second dust removal device 5, located between the heat storage and release furnace group 4 and the gas storage device 6. The second dust removal device 5 is capable of removing dust from the converter gas after it has released heat in the heat storage and 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. The second dust removal device 5 performs fine dust removal on the dusty converter gas, and an electrostatic precipitator may be used to ensure that the treated converter gas meets the requirements of the compressor.

[0054] The pressurizing device 8 can be located upstream or downstream of the heat storage and heat release furnace group 4. Preferably, the pressurizing device 8 is located upstream of the heat storage and heat release furnace group 4, that is, the pressurizing device 8 is located between the heat storage and heat release furnace group 4 and the gas storage device 6. The gas storage device 6 is mainly used to store low-pressure pure converter gas at room temperature. A large gas tank can be used to avoid the impact of direct use of intermittent converter gas on the normal production of the blast furnace. 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 heat storage and heat release furnace 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 absorbing heat in the first regenerative furnace 41 or the second regenerative furnace 42 equal to the pressure in the blast furnace 9, thereby ensuring the normal production of blast furnace ironmaking.

[0055] The processing system for the converter gas used in blast furnace ironmaking production also includes a purification treatment device 7. The purification treatment device 7 is located between the pressurizing device 8 and the gas storage device 6. The purification treatment device 7 removes CO2, desulfurizes, dehydrates, deoxidizes and denitrifies the converter gas discharged from the gas storage device 6. The purification treatment device 7 includes but is not limited to dust removal, pressurization, desulfurization, deoxidation, dehydration, decarbonization, denitrification, and gas enrichment. The purification treatment device 7 can adopt existing technology products. In actual production, only certain processing links and devices can be used according to the specific composition of the converter gas. The order of each processing link and device can also be adjusted accordingly according to the specific processing technology of each link.

[0056] The following describes a method for processing converter gas for blast furnace ironmaking. The method employs the above-mentioned converter gas processing system for blast furnace ironmaking. The method comprises the following steps:

[0057] Step 1: The 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. The converter exhaust gas that does not meet the recovery conditions is dust-laden air, and the converter exhaust gas that meets the recovery conditions is converter gas. The first dust removal equipment 3 performs dust removal on the dust-laden air. The converter gas can enter the first regenerative furnace 41 of the regenerative heat release furnace group 4 to release heat, and the first regenerative heat release furnace 41 stores heat (i.e., is in a heat storage state). The converter gas after heat release enters the gas storage device 6 for storage, and the gas storage device 6 discharges the converter gas into the second regenerative heat release furnace 42 of the regenerative heat release furnace group 4 to absorb heat, and the second regenerative heat release furnace 42 releases heat (i.e., is in a heat release state). The pressurizing device 8 pressurizes the converter gas discharged from the gas storage device 6, as shown in FIG3 .

[0058] Step 2, the gas detection device 2 detects the composition and content of the converter exhaust gas, and determines whether the converter exhaust gas meets the recovery conditions. The converter exhaust gas that does not meet the recovery conditions is dust-laden air, and the converter exhaust gas that meets the recovery conditions is converter gas; the first dust removal equipment 3 performs dust removal on the dust-laden air; the converter gas can enter the second regenerative furnace 42 of the regenerative heat release furnace group 4 to release heat, and the second regenerative heat release furnace 42 stores heat (i.e., is in a heat storage state); the converter gas after heat release enters the gas storage device 6 for storage, and the gas storage device 6 discharges the converter gas into the first regenerative heat release furnace 41 of the regenerative heat release furnace group 4 to absorb heat, and the first regenerative heat release furnace 41 releases heat (i.e., is in a heat release state); the pressurizing device 8 pressurizes the converter gas discharged from the gas storage device 6, as shown in Figure 4;

[0059] Step 3. Repeat steps 1 and 2 in sequence.

[0060] In steps 1 and 2, gas detection device 2 primarily detects the O2 or CO content in the converter exhaust gas to determine whether it meets the recovery conditions. If the converter exhaust gas does not meet the recovery conditions, it enters first dust removal equipment 3, where it is removed and discharged into the air without being recycled. If the converter exhaust gas meets the recovery conditions, it enters thermal storage and release furnace group 4 for recycling.

[0061] For example, if the O2 content detected by gas detection device 2 is greater than 1% or the CO content is less than 10%, it indicates that the oxidation reaction between O2 and the high-temperature molten iron in converter 1 has essentially ended, and the converter exhaust gas does not meet the recovery conditions. At this time, the CO content in the exhaust gas is very low and has no recovery value, and its discharge into the air will cause little air pollution. If the O2 content detected by gas detection device 2 is ≤1% or the CO content is ≥10%, the converter exhaust gas meets the recovery conditions.

[0062] 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, and the first regenerator 41 and the second regenerator 42 are not connected to the converter 1. The converter exhaust gas enters the first dust removal device 3 instead of 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, and the first dust removal device 3 is not connected to the converter 1. The converter exhaust gas enters the first regenerator 41 or the second regenerator 42 instead of the first dust removal device 3.

[0063] In step 1, when the converter gas enters the first regenerative furnace 41 from the heat storage inlet of the first regenerative furnace 41 to release heat and is discharged from the heat storage outlet of the first regenerative furnace 41, the first regenerative furnace 41 stores heat; when the converter gas does not enter the first regenerative furnace 41, the first regenerative furnace 41 is in a heat preservation state; when the converter gas enters the second regenerative furnace 42 from the heat release inlet of the second regenerative furnace 42 to absorb heat and is discharged from the heat release outlet of the second regenerative furnace 42, the second regenerative furnace 42 releases heat, and the converter gas absorbs heat from the second regenerative furnace 42 and enters the blast furnace 9.

[0064] In step 1, when the converter gas (1400°C-1500°C) enters the first regenerator 41 from the regenerator inlet and releases heat, and is discharged from the regenerator outlet of the first regenerator 41, the regenerator in the first regenerator 41 stores heat. The regenerator can filter out iron-containing dust in the converter gas. The converter gas releases heat. After the heat release, the temperature of the converter gas is 100°C-150°C and the pressure is 4KPa-6KPa. When the converter gas enters the second regenerator 42 from the heat release inlet and absorbs heat, and is discharged from the heat release outlet of the second regenerator 42, the regenerator in the second regenerator 42 releases heat. The converter gas can then carry away the iron-containing dust in the regenerator and send it into the blast furnace 9.

[0065] In step 2, when the converter gas enters the second regenerative furnace 42 from the heat storage inlet of the second regenerative furnace 42 to release heat and is discharged from the heat storage outlet of the second regenerative furnace 42, the second regenerative furnace 42 stores heat; when the converter gas does not enter the second regenerative furnace 42, the second regenerative furnace 42 is in a heat preservation state; when the converter gas enters the first regenerative furnace 41 from the heat release inlet of the first regenerative furnace 41 to absorb heat and is discharged from the heat release outlet of the first regenerative furnace 41, the first regenerative furnace 41 releases heat, and the converter gas enters the blast furnace 9 after absorbing heat from the first regenerative furnace 41.

[0066] In step 2, when the converter gas (1400°C-1500°C) enters the second regenerator 42 from the regenerator inlet and releases heat and is discharged from the regenerator outlet of the second regenerator 42, the regenerator in the second regenerator 42 accumulates heat. The regenerator can filter out iron-containing dust in the converter gas. The converter gas releases heat. After heat release, the converter gas has a temperature of 100°C-150°C and a pressure of 4KPa-6KPa. When the converter gas enters the first regenerator 41 from the heat release inlet and absorbs heat and is discharged from the heat release outlet of the first regenerator 41, the regenerator in the first regenerator 41 releases heat. The converter gas can then carry away the iron-containing dust in the regenerator and send it into the blast furnace 9.

[0067] In step 1, when the heat stored in the heat storage body in the second heat storage furnace 42 is insufficient to heat the converter gas to the temperature required by the blast furnace 9 (850°C-950°C if injected from the lower inlet 92 of the furnace body, 1150°C-1250°C if injected from the tuyere 91), the heating device in the second heat storage furnace 42 is started to heat the heat storage body in the second heat storage furnace 42.

[0068] 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 (850°C-950°C if injected from the lower inlet 9 of the furnace body, 1150°C-1250°C if injected from the tuyere 91), the heating device in the first heat storage furnace 41 is started to heat the heat storage body in the first heat storage furnace 41.

[0069] In step 1 and step 2, the second dust removal device 5 is used to perform fine dust removal on the converter gas after heat release in the heat storage and heat release furnace group 4. After fine dust removal, clean converter gas (dust content less than 10mg / m3) with room temperature (about 70°C) and low pressure (3KPa-4KPa) is obtained. 3 After the fine dust removal treatment, the converter gas enters the gas storage device 6 for storage.

[0070] In step 1 and step 2, the converter gas discharged from the gas storage device 6 is subjected to treatments such as removal of CO2, desulfurization, dehydration, deoxidation and denitrification by using the purification treatment equipment 7 .

[0071] In steps 1 and 2, the pressurizing device 8 pressurizes the converter gas discharged from the gas storage device 6 before it enters the thermal storage and heat release furnace group 4. Preferably, the pressurizing device 8 pressurizes the converter gas discharged from the purification and treatment equipment 7 before it enters the thermal storage and heat release furnace group 4. The pressure of the pressurized converter gas is greater than the pressure within the blast furnace 9. For example, the pressure of the pressurized converter gas is at least 0.1 MPa higher than the pressure within the blast furnace 9 to ensure normal blast furnace ironmaking production.

[0072] The pressurizing device 8 can not only pressurize the converter gas discharged from the gas storage device 6 before entering the heat storage and 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 can contain decarbonized blast furnace gas, purified and reformed natural gas or coke oven gas, as shown in Figure 6.

[0073] The following briefly introduces the specific process of the method for treating converter gas for blast furnace ironmaking production, taking the production cycle of converter 1 as an example, which is usually about 30 minutes and the emission cycle of converter gas as a example, which is usually about 12 minutes.

[0074] 0 minutes - 12 minutes:

[0075] The converter 1 discharges gas, and the gas detection device 2 detects that the converter exhaust gas meets the recovery conditions. The converter 1 exhaust gas (converter gas) enters the first regenerative furnace 41 of the regenerative and heat-releasing furnace group 4 to release heat. The converter gas after heat release enters the second dust removal equipment 5 for fine dust removal. The converter gas after fine dust removal enters the gas storage device 6 for storage. The gas storage device 6 discharges the converter gas into the purification treatment equipment 7 for purification. The purified converter gas enters the pressurizing device 8 for pressurization. The pressurized converter gas enters the second regenerative furnace 42 of the regenerative and heat-releasing furnace group 4 to absorb heat. The converter gas after heat absorption enters the blast furnace 9.

[0076] 12 minutes - 30 minutes:

[0077] The converter 1 discharges gas, and the gas detection device 2 detects that the converter exhaust gas does not meet the recovery conditions. The converter 1 exhaust gas (dust-laden air) enters the first dust removal equipment 3 for dust removal and then is discharged into the air. The converter 1 exhaust gas (dust-laden air) does not enter the heat storage and release furnace group 4. The gas storage device 6 discharges the converter gas into the purification treatment equipment 7 for purification. The purified converter gas enters the pressurizing device 8 for pressurization. The pressurized converter gas enters the second heat storage furnace 42 of the heat storage and release furnace group 4 to absorb heat. The converter gas after heat absorption enters the blast furnace 9.

[0078] 30 minutes to 42 minutes:

[0079] The converter 1 discharges gas, and the gas detection device 2 detects that the converter exhaust gas meets the recovery conditions. The converter 1 exhaust gas (converter gas) enters the second regenerative furnace 42 of the regenerative and heat-releasing furnace group 4 to release heat. The converter gas after heat release enters the second dust removal equipment 5 for fine dust removal. The converter gas after fine dust removal enters the gas storage device 6 for storage. The gas storage device 6 discharges the converter gas into the purification treatment equipment 7 for purification. The purified converter gas enters the pressurizing device 8 for pressurization. The pressurized converter gas enters the first regenerative furnace 41 of the regenerative and heat-releasing furnace group 4 to absorb heat. The converter gas after heat absorption enters the blast furnace 9.

[0080] 42 minutes - 60 minutes:

[0081] The converter 1 discharges gas, and the gas detection device 2 detects that the converter exhaust gas does not meet the recovery conditions. The converter 1 exhaust gas (dust-laden air) enters the first dust removal equipment 3 for dust removal and then is discharged into the air. The converter 1 exhaust gas (dust-laden air) does not enter the heat storage and release furnace group 4. The gas storage device 6 discharges the converter gas into the purification treatment equipment 7 for purification. The purified converter gas enters the pressurizing device 8 for pressurization. The pressurized converter gas enters the first heat storage furnace 41 of the heat storage and release furnace group 4 to absorb heat. The converter gas after absorbing heat enters the blast furnace 9.

[0082] Repeat the process from 0 minutes to 60 minutes in sequence.

[0083] The present invention first analyzes the composition of the gas discharged from converter steelmaking and then performs treatment before injection into the blast furnace, which can greatly improve the efficiency of the treatment system.

[0084] The present invention can be provided with a heat storage furnace system, which can efficiently store the heat of the 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.

[0085] In the present invention, when the regenerative furnace is in the "regenerative" state, it has a certain coarse dust removal function for the high-temperature low-pressure converter gas, creating favorable conditions for improving the efficiency of subsequent fine dust removal.

[0086] When the regenerative furnace is in the "heat release" state, the low-temperature and high-pressure converter gas is heated and at the same time, the iron-containing dust intercepted during the "heat storage" is taken away, creating conditions for achieving zero solid waste emissions.

[0087] The regenerative furnace system mentioned in the technical solution of the present invention fully utilizes the periodicity of converter gas generated by converter steelmaking to achieve a reasonable decomposition of "heat storage" and "heat release" without affecting the normal production of blast furnace ironmaking.

[0088] The above description is merely a specific embodiment of the present invention and is not intended to limit 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 features, technical solutions, technical solutions, and embodiments of the present invention may be freely combined.

[0089] The above description is merely a specific embodiment of the present invention and is not intended to limit 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 of the present invention may be freely combined with each other, with each other's technical solutions, and with each other's technical solutions.

Claims

1. A system for processing converter gas for blast furnace ironmaking production, wherein: The processing system for converter gas used in blast furnace ironmaking production comprises a gas detection device (2), a heat storage and heat release furnace group (4), a gas storage device (6) and a pressurizing device (8) which are sequentially connected via a gas transmission pipeline, and the processing system for converter gas used in blast furnace ironmaking production also comprises a first dust removal device (3); The gas detection device (2) is capable of detecting the composition and content of the converter exhaust gas, and judging whether the converter exhaust gas meets the recovery conditions. If the converter exhaust gas does not meet the recovery conditions, it is dusty air; if the converter exhaust gas meets the recovery conditions, it is converter coal gas. The first dust removal device (3) is capable of performing dust removal treatment on the dust-laden air; The heat storage and heat release furnace group (4) comprises a first heat storage furnace (41) and a second heat storage furnace (42), the converter gas can enter the first heat storage furnace (41) or the second heat storage furnace (42) to release heat, and the first heat storage furnace (41) and the second heat storage furnace (42) can both store and release heat; The gas storage device (6) can store the converter gas after releasing heat, and the gas storage device (6) can also transport the converter gas to the heat storage and heat release furnace group (4). When the converter gas enters the first heat storage furnace (41) to release heat, the converter gas discharged from the gas storage device (6) can enter the second heat storage furnace (42) to absorb heat; when the converter gas enters the second heat storage furnace (42) to release heat, the converter gas discharged from the gas storage device (6) can enter the first heat storage furnace (41) to absorb heat; and the converter gas after absorbing heat can enter the blast furnace (9); The pressurizing device (8) is capable of pressurizing the converter gas discharged from the gas storage device (6).

2. The system for processing converter gas for blast furnace ironmaking production according to claim 1, wherein: The first regenerative furnace (41) comprises a regenerative inlet, a regenerative outlet, a heat release inlet and a heat release outlet. When the converter gas enters the first regenerative furnace (41) from the regenerative inlet to release heat and is discharged from the regenerative outlet of the first regenerative furnace (41), the first regenerative furnace (41) is in a regenerative state; when the converter gas enters the first regenerative furnace (41) from the heat release inlet to absorb heat and is discharged from the heat release outlet of the first regenerative furnace (41), the first regenerative furnace (41) is in a heat release state.

3. The system for processing converter gas for blast furnace ironmaking production according to claim 2, wherein: The second regenerative furnace (42) also comprises a regenerative inlet, a regenerative outlet, a heat release inlet and a heat release outlet. When the converter gas enters the second regenerative furnace (42) from the regenerative inlet to release heat and is discharged from the regenerative outlet of the second regenerative furnace (42), the second regenerative furnace (42) is in a regenerative state; when the converter gas enters the second regenerative furnace (42) from the heat release inlet to absorb heat and is discharged from the heat release outlet of the second regenerative furnace (42), the second regenerative furnace (42) is in a heat release state.

4. The system for processing converter gas for blast furnace ironmaking production according to claim 3, wherein: The heat storage inlet and heat release outlet of the first heat storage furnace (41) are both located at the upper part of the first heat storage furnace (41), and the heat storage outlet and heat release inlet of the first heat storage furnace (41) are both located at the lower part of the first heat storage furnace (41). The heat storage inlet and heat release outlet of the second heat storage furnace (42) are also located at the upper part of the second heat storage furnace (42), and the heat storage outlet and heat release inlet of the second heat storage furnace (42) are also located at the lower part of the second heat storage furnace (42). The first heat storage furnace (41) and the second heat storage furnace (42) are both provided with a heat storage body and a heating device, and the heat storage body contains a through hole that penetrates in the vertical direction.

5. The system for processing converter gas for blast furnace ironmaking production according to claim 3, wherein: When the first regenerative furnace (41) is in a heat releasing state, the heat releasing outlet of the first regenerative furnace (41) is connected to the lower inlet (92) or the tuyere (91) of the furnace body of the blast furnace (9); when the second regenerative furnace (42) is in a heat releasing state, the heat releasing outlet of the second regenerative furnace (42) is connected to the lower inlet (92) or the tuyere (91) of the furnace body of the blast furnace (9).

6. A method for treating converter gas for blast furnace ironmaking production, wherein: The method for treating converter gas for blast furnace ironmaking production comprises the following steps in sequence: Step 1, the gas detection device (2) detects the composition and content of the converter exhaust gas, and determines whether the converter exhaust gas meets the recovery conditions. The converter exhaust gas that does not meet the recovery conditions is dust-containing air, and the converter exhaust gas that meets the recovery conditions is converter gas; the first dust removal equipment (3) performs dust removal on the dust-containing air; the converter gas enters the first heat storage furnace (41) of the heat storage and heat release furnace group (4) to release heat, and the first heat storage furnace (41) stores heat; the converter gas after heat release enters the gas storage device (6) for storage, and the gas storage device (6) discharges the converter gas into the second heat storage furnace (42) of the heat storage and heat release furnace group (4) to absorb heat, and the second heat storage furnace (42) releases heat, and the converter gas after heat absorption enters the blast furnace (9); the pressurizing device (8) pressurizes the converter gas discharged from the gas storage device (6); Step 2, the 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. The converter exhaust gas that does not meet the recovery conditions is dust-containing air, and the converter exhaust gas that meets the recovery conditions is converter gas; the first dust removal device (3) performs dust removal on the dust-containing air; the converter gas enters the second heat storage furnace (42) of the heat storage and heat release furnace group (4) to release heat, and the second heat storage furnace (42) stores heat; the converter gas after heat release enters the gas storage device (6) for storage, and the gas storage device (6) discharges the converter gas into the first heat storage furnace (41) of the heat storage and heat release furnace group (4) to absorb heat, and the first heat storage furnace (41) releases heat. The converter gas after heat absorption enters the blast furnace (9); the pressurizing device (8) pressurizes the converter gas discharged from the gas storage device (6); Step 3. Repeat steps 1 and 2 in sequence.

7. The method for treating converter gas for blast furnace ironmaking according to claim 6, wherein: In step 1 and step 2, the gas detection device (2) determines whether the recovery conditions are met by detecting the content of O2 or CO in the converter exhaust gas; when the converter exhaust gas does not meet the recovery conditions, the converter exhaust gas enters the first dust removal equipment (3) for dust removal and then is discharged into the air; when the converter exhaust gas meets the recovery conditions, the converter exhaust gas enters the heat storage and heat release furnace group (4) for recovery and utilization.

8. The method for treating converter gas for blast furnace ironmaking production according to claim 6, wherein: In step 1 and step 2, when the gas detection device (2) detects that the O2 content in the converter exhaust gas is greater than 1% or the CO content is less than 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; In step 1 and step 2, when the converter exhaust gas meets the recovery conditions, the first regenerative furnace (41) or the second regenerative furnace (42) is connected to the converter (1), the first dust removal equipment (3) is not connected to the converter (1), and the converter exhaust gas enters the first regenerative furnace (41) or the second regenerative furnace (42) instead of the first dust removal equipment (3).

9. The method for treating converter gas for blast furnace ironmaking production according to claim 6, wherein: In step 1, when the converter gas enters the first regenerative furnace (41) to release heat, the regenerative body in the first regenerative furnace (41) stores heat and filters out iron-containing dust in the converter gas. When the converter gas enters the second regenerative furnace (42) to absorb heat, the converter gas takes away the iron-containing dust in the regenerative body in the second regenerative furnace (42) and sends it into the blast furnace (9). In step 2, when the converter gas enters the second regenerative furnace (42) to release heat, the regenerative body in the second regenerative furnace (42) stores heat and filters out iron-containing dust in the converter gas. When the converter gas enters the first regenerative furnace (41) to absorb heat, the converter gas takes away the iron-containing dust in the regenerative body in the first regenerative furnace (41) and sends it into the blast furnace (9).

10. The method for treating converter gas for blast furnace ironmaking production according to claim 6, wherein: In step 1, when the heat stored in the heat storage body in the second heat storage furnace (42) is insufficient to heat the converter gas to the temperature required by the blast furnace (9), the heating device in the second heat storage furnace (42) is started to heat the heat storage body in the second heat storage furnace (42); 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 started to heat the heat storage body in the first heat storage furnace (41).

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