A system for producing sponge iron by coupling a gasification furnace with a gas-based shaft furnace
By using a gasifier-gas-based vertical furnace coupling system and high-temperature desulfurization and decarbonization technology, the problems of high desulfurization energy consumption and low energy utilization efficiency in the production of sponge iron in dry coal powder gasification vertical furnaces have been solved, achieving more efficient and cleaner sponge iron production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- CHANGZHENG ENG
- Filing Date
- 2025-05-26
- Publication Date
- 2026-07-14
AI Technical Summary
In the existing method of producing sponge iron using dry pulverized coal gasification shaft furnace, the desulfurization process is energy-intensive, costly, and prone to secondary pollution. The single utilization method of shaft furnace gas leads to low energy efficiency and limits economic benefits.
The system adopts a gasifier and gas-based vertical furnace coupling system. Through coal pretreatment, syngas mixing, dust removal, desulfurization and decarbonization devices, the mixed gas is treated at high temperature using high-temperature desulfurizing and decarbonizing agents, achieving one-step dust removal and efficient desulfurization and decarbonization, reducing equipment investment and heat loss.
It improves the cleanliness and efficiency of sponge iron production, reduces costs, achieves more efficient energy utilization and reduces secondary pollution, thus achieving the goal of clean production with low energy consumption.
Smart Images
Figure CN224494235U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of coal gasification technology, and in particular to a system for producing sponge iron by coupling a gasifier and a gas-based vertical furnace. Background Technology
[0002] Sponge iron is an indispensable impurity diluent in electric arc furnace (EAF) steelmaking for producing pure and high-quality steel, and it is also the best coolant in converter steelmaking. Global production of sponge iron and hot-pressed sponge iron briquettes is approaching 60 million tons per year. Most of the world's sponge iron is produced using gas-based vertical shaft furnaces, with a small amount produced directly in coal-fired rotary kilns. The mainstream technology for sponge iron production is vertical shaft furnace gas-based reduction, using natural gas as fuel. Due to the scarcity of natural gas resources, sponge iron production in China has not developed as expected, with output currently only reaching 600,000-800,000 tons per year.
[0003] In existing technologies, a method for producing sponge iron using dry coal powder gasification vertical furnaces has emerged, overcoming the limitations of natural gas production in gas-based methods. This method also enables large-scale production, achieving the goals of low-energy-consumption clean production and CO2 emission reduction.
[0004] However, the existing method of producing sponge iron by dry coal gasification shaft furnace usually adopts wet desulfurization in the desulfurization process, which has problems such as high energy consumption, high cost and easy generation of secondary pollution. Moreover, the utilization of shaft furnace gas is relatively simple, which does not fully realize its potential as an energy source, thus limiting the efficient use of energy and the economic benefits of the system.
[0005] Therefore, a new technological solution is urgently needed to address the problems of low energy efficiency, high desulfurization costs, and secondary pollution in existing technologies, and to achieve cleaner and more efficient sponge iron production. Utility Model Content
[0006] The purpose of this invention is to provide a system for producing sponge iron by coupling a gasifier and a gas-based vertical furnace, so as to overcome or at least mitigate at least one of the above-mentioned defects of the prior art.
[0007] To achieve the above objectives, this utility model provides a system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace, characterized in that it includes a coal pretreatment device 1, a conveying device 2, a gasifier 3, a dust collector 4, a high-temperature desulfurization device 5, a high-temperature decarburization device 6, and a gas-based vertical shaft furnace 7; wherein...
[0008] Coal pretreatment unit 1 pretreatments the received raw coal;
[0009] Gasifier 3 is connected to conveying device 2 and mixer. It receives raw coal processed by coal pretreatment device 1 through conveying device 2, reacts to obtain syngas, and outputs the syngas to the mixer. The syngas includes hydrogen and carbon monoxide.
[0010] The mixer is also connected to the gas-based vertical shaft furnace 7, receives the top gas generated by the gas-based vertical shaft furnace 7, mixes the top gas with syngas to obtain a mixed gas, and outputs the mixed gas to the dust collector 4; wherein, the temperature of the syngas is 1200℃-1360℃, and the temperature of the mixed gas is 1120℃-1280℃.
[0011] Dust collector 4 is connected to the mixer, receives the mixed gas output from the mixer, performs dust removal on the mixed gas, and outputs the dust-removed mixed gas to the high-temperature desulfurization device 5; the temperature of the dust-removed mixed gas is 1070℃-1230℃;
[0012] The high-temperature desulfurization device 5 is connected to the dust collector 4 and the high-temperature decarbonization device 6. It uses a high-temperature desulfurizing agent to perform desulfurization treatment on the mixed gas after dust removal, reducing the H2S content in the mixed gas, and outputting the desulfurized mixed gas to the high-temperature decarbonization device 6.
[0013] The high-temperature decarbonization device 6 is connected to the high-temperature desulfurization device 5 and the gas-based vertical furnace 7. It performs decarbonization treatment on the desulfurized mixed gas to reduce the CO2 content in the mixed gas and outputs the decarbonized mixed gas to the gas-based vertical furnace 7. The temperature of the decarbonized mixed gas is 920℃-1080℃.
[0014] The gas-based vertical shaft furnace 7 contains iron ore and / or oxide pellets, and receives the decarburized mixed gas input from the high-temperature decarburization device 6, which reacts to produce sponge iron and the furnace top gas.
[0015] Preferably, the high-temperature decarbonization device 6 is also connected to the conveying device 2 for outputting the decarbonized CO2 into the conveying device 2;
[0016] The conveying device 2 uses CO2 to feed the raw coal processed by the coal pretreatment device 1 into the gasifier 3.
[0017] Preferably, the operating pressure for preparing syngas in gasifier 3 is 2.0 MPa-6.5 MPa.
[0018] Preferably, the high-temperature desulfurization device 5 uses a desulfurizing agent to perform the desulfurization operation, and the ambient temperature is 1020℃-1180℃. The desulfurizing agent includes metal oxide and / or composite metal oxide adsorbent particles.
[0019] Preferably, the metal oxide includes at least one of iron oxide, zinc oxide, copper oxide, calcium oxide, and cerium oxide, and the composite metal oxide includes at least one of iron-calcium, copper-manganese, zinc ferrite, and zinc titanate metal oxides.
[0020] Preferably, the high-temperature decarbonization device 6 uses a decarbonization agent to perform the decarbonization operation, thereby achieving CO2 desorption and capture. The ambient temperature is 970℃-1130℃, and the decarbonization agent includes CaO-based and / or Li4SiO4-based adsorbent particles.
[0021] Preferably, the operating pressure inside the gas-based vertical shaft furnace 7 is 1.7MPa-6.2MPa.
[0022] Preferably, the carbon-containing raw materials include coal, biomass, and / or waste.
[0023] Preferably, the dust collector 4 includes a cyclone dust collector.
[0024] This utility model has the following advantages due to the adoption of the above technical solution:
[0025] In this invention, the top gas from the vertical shaft furnace is mixed with the syngas from the gasifier, and dust is removed in one step, reducing heat loss and equipment investment. Furthermore, this invention uses the top gas from the vertical shaft furnace to cool the syngas from the gasifier. The cooled mixture, at a high temperature, undergoes desulfurization using metal oxide and / or composite metal oxide adsorbent particles, and decarbonization using a decarbonizing agent. No additional cooling equipment is required, reducing costs, improving efficiency and energy utilization, and achieving cleaner and more efficient sponge iron production. Attached Figure Description
[0026] Figure 1 This is a schematic diagram of a system for producing sponge iron by coupling a gasifier and a gas-based vertical furnace, as provided in Embodiment 1 of this utility model. Detailed Implementation
[0027] In the accompanying drawings, the same or similar reference numerals are used to denote the same or similar elements or elements having the same or similar functions. The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.
[0028] In the description of this utility model, the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this utility model.
[0029] Where there is no conflict, the technical features of the various embodiments and implementations of this utility model can be combined with each other, and are not limited to the embodiments or implementations in which the technical feature is located.
[0030] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that the technical solution and design principle of the present invention will be described in detail below with reference to only one optimized technical solution, but the protection scope of the present invention is not limited thereto.
[0031] The following terms are used in this document, and their meanings are explained below for ease of understanding. Those skilled in the art should understand that the following terms may have other names, but without departing from their meanings, any other names should be considered consistent with the terms listed herein.
[0032] Example 1
[0033] Embodiment 1 of this utility model provides a system for producing sponge iron by coupling a gasifier and a gas-based vertical furnace. Figure 1 A schematic diagram of the system structure is shown. For example... Figure 1 As shown, the system includes a coal pretreatment unit 1, a conveying unit 2, a gasifier 3, a dust collector 4, a high-temperature desulfurization unit 5, a high-temperature decarbonization unit 6, and a gas-based vertical shaft furnace 7. Among them:
[0034] The coal pretreatment unit 1 pretreatments the received raw coal. Carbonaceous raw materials include coal, biomass, and / or waste, among other carbonaceous substances. This pretreatment includes pulverization pretreatment, which involves grinding the raw coal to obtain coal powder. In a preferred embodiment, this pretreatment includes slurry pretreatment, for example, mixing coal powder, water, and additives to form a coal slurry.
[0035] The conveying device 2 transports the raw coal processed by the coal pretreatment device 1 to the gasifier 3. The conveying device 2 can be a chain conveyor, a pneumatic conveying system, a high-pressure pump, or other similar devices. In a preferred embodiment, the conveying device 2 is a pneumatic conveying system, and the processed raw coal can be transported using CO2 obtained from the high-temperature decarbonization device 6. Initially, the conveying device 2 needs to provide gas for transporting the raw coal; after normal operation, it only needs to utilize the CO2 provided by the high-temperature decarbonization device 6 to perform the transport, eliminating the need for additional gas to transport the raw coal.
[0036] The gasifier 3 is connected to the conveying device 2 and the mixer. The conveying device 2 receives raw coal processed by the coal pretreatment device 1, reacts it to produce syngas, and outputs the syngas to the mixer. The syngas contains hydrogen and carbon monoxide. The preferred operating pressure for syngas production in the gasifier 3 is 2.0 MPa-6.5 MPa. The temperature of the syngas is 1200℃-1360℃. The slag from the reaction in the gasifier 3 is discharged through a valve at the bottom of the gasifier.
[0037] The mixer is also connected to the gas-based vertical shaft furnace 7, receiving the top gas generated by the furnace 7, mixing the top gas with syngas to obtain a mixed gas, and outputting the mixed gas to the dust collector 4; wherein the temperature of the syngas is 1200℃-1360℃, and the temperature of the mixed gas is 1120℃-1280℃. The mixer is a three-way pipe that receives the syngas from the gasifier 3 and the top gas from the gas-based vertical shaft furnace 7, mixes them, and then transmits them to the dust collector 4. This mixer can also be other independent equipment, for example, it may include a mixing section and an output section. After receiving the syngas from the gasifier 3 and the top gas from the gas-based vertical shaft furnace 7, the two gases are first mixed in the mixing section. After detecting that the mixing process is complete, the mixed gas is then transmitted to the dust collector 4 through the output section. The mixing process includes, for example, detecting the temperature of the mixed gas and adjusting the input of the syngas and top gas according to the temperature range; for example, if the temperature of the mixed gas is low, the input of the top gas is reduced, and if the temperature is high, the input of the top gas is increased.
[0038] Dust collector 4 is connected to a mixer, receives the mixed gas output from the mixer, performs dust removal on the mixed gas, and outputs the dust-removed mixed gas to the high-temperature desulfurization unit 5; the temperature of the dust-removed mixed gas is 1070℃-1230℃. Dust collector 4 includes a cyclone dust collector, but other dust removal devices may also be used. The dust content of the dust-removed mixed gas is no greater than 100g / m³. 3 .
[0039] A high-temperature desulfurization unit 5 is connected to a dust collector 4 and a high-temperature decarbonization unit 6. It uses a high-temperature desulfurizing agent to desulfurize the mixed gas after dust removal, reducing the H2S content in the mixed gas, and then outputs the desulfurized mixed gas to the high-temperature decarbonization unit 6. The high-temperature desulfurization unit 5 performs the desulfurization operation using a desulfurizing agent at an ambient temperature of 1020℃-1180℃. The desulfurizing agent includes metal oxides and / or composite metal oxide adsorbent particles. The metal oxides include at least one of iron oxide, zinc oxide, copper oxide, calcium oxide, and cerium oxide, and the composite metal oxides include at least one of iron-calcium, copper-manganese, zinc ferrite, and zinc titanate metal oxides.
[0040] The high-temperature decarbonization unit 6 is connected to the high-temperature desulfurization unit 5 and the gas-based vertical shaft furnace 7. It performs decarbonization treatment on the desulfurized mixed gas, reducing the CO2 content in the mixed gas, and outputs the decarbonized mixed gas to the gas-based vertical shaft furnace 7. The temperature of the decarbonized mixed gas is 920℃-1080℃. The high-temperature decarbonization unit 6 uses a decarbonizing agent to perform the decarbonization operation, achieving CO2 desorption and capture. The ambient temperature is 970℃-1130℃. The decarbonizing agent includes CaO-based and / or Li4SiO4-based adsorbent particles. The high-temperature decarbonization unit 6 is also connected to the conveying device 2, which outputs the decarbonized CO2 into the conveying device 2. The conveying device 2 uses the CO2 to feed the raw coal processed by the coal pretreatment unit 1 into the gasifier 3. The remaining high-concentration CO2 obtained from decarbonization can be captured, reducing carbon emissions from the entire process system.
[0041] The gas-based shaft furnace 7 contains iron ore and / or oxide pellets, and receives the decarburized mixed gas from the high-temperature decarburization device 6, reacting to produce sponge iron and the furnace top gas. The operating pressure inside the gas-based shaft furnace 7 is 1.7 MPa–6.2 MPa.
[0042] By employing the system provided in this embodiment, the top gas from the vertical shaft furnace is mixed with the syngas from the gasifier, and dust is removed in one step, reducing heat loss and equipment investment. Furthermore, this invention utilizes the top gas from the vertical shaft furnace to cool the syngas from the gasifier. The cooled mixture, at a high temperature, undergoes desulfurization using metal oxide and / or composite metal oxide adsorbent particles, and decarbonization using a decarbonizing agent. No additional cooling equipment is required, reducing costs, improving efficiency and energy utilization, and achieving cleaner and more efficient sponge iron production.
[0043] Example 2
[0044] Embodiment 2 of this utility model provides a system for producing sponge iron by coupling a gasifier and a gas-based vertical furnace, see reference. Figure 1 As shown, it includes a coal pretreatment device 1, a conveying device 2, a gasifier 3, a dust collector 4, a high-temperature desulfurization device 5, a high-temperature decarbonization device 6, and a gas-based vertical shaft furnace 7.
[0045] Pretreatment device 1 performs powdering or pulping pretreatment on carbon-containing raw materials.
[0046] The conveying device 2 delivers the pretreated carbon-containing raw material to the gasifier 3.
[0047] The carbon-containing raw material in gasifier 3 reacts with water vapor and oxygen to produce syngas H2+CO, and the output syngas temperature is 1200℃-1360℃.
[0048] The mixer receives syngas and circulating gas generated by the gas-based vertical furnace 7, and uses the circulating gas to mix and cool the syngas to obtain a mixed gas at a temperature of 1100℃-1200℃.
[0049] Dust collector 4 performs cyclone dust removal on the mixed gas, and the dust content of the mixed gas after dust removal is no more than 100g / m³. 3 .
[0050] The high-temperature desulfurization unit 5 receives the mixed gas after dust removal by the dust collector 4, removes H2S from the mixed gas, recovers sulfur, and then removes CO2 through the high-temperature decarbonization unit 6. Part of the CO2 is recycled to the conveying device 2 and re-enters the gasifier 3 to suppress the generation of CO2 during the gasification process, while the other part of the high-concentration CO2 is captured to reduce the carbon emissions of the entire process system. The temperature of the mixed gas after decarbonization is 920℃-1080℃.
[0051] The gas-based vertical shaft furnace 7 receives the mixed gas after desulfurization and decarburization treatment, and uses the mixed gas to react with the input iron ore and / or oxide pellets to obtain sponge iron products and recycled gas.
[0052] By employing the system provided in this embodiment, the top gas from the vertical shaft furnace is mixed with the syngas from the gasifier, and dust is removed in one step, reducing heat loss and equipment investment. Furthermore, this invention utilizes the top gas from the vertical shaft furnace to cool the syngas from the gasifier. The cooled mixture, at a high temperature, undergoes desulfurization using metal oxide and / or composite metal oxide adsorbent particles, and decarbonization using a decarbonizing agent. No additional cooling equipment is required, reducing costs, improving efficiency and energy utilization, and achieving cleaner and more efficient sponge iron production.
[0053] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Those skilled in the art should understand that modifications can be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.
Claims
1. A system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace, characterized in that, It includes a coal pretreatment device (1), a conveying device (2), a gasifier (3), a dust collector (4), a high-temperature desulfurization device (5), a high-temperature decarbonization device (6), and a gas-based vertical shaft furnace (7); characterized in that: The coal pretreatment unit (1) pretreatments the received raw coal; The gasifier (3) is connected to the conveying device (2) and the mixer. The conveying device (2) receives the raw coal processed by the coal pretreatment device (1), reacts to obtain syngas, and outputs the syngas to the mixer. The syngas includes hydrogen and carbon monoxide. The mixer is also connected to a gas-based vertical furnace (7), receives the top gas generated by the gas-based vertical furnace (7), mixes the top gas with syngas to obtain a mixed gas, and outputs the mixed gas to the dust collector (4); wherein, the temperature of the syngas is 1200℃-1360℃, and the temperature of the mixed gas is 1120℃-1280℃. The dust collector (4) is connected to the mixer, receives the mixed gas output by the mixer, performs dust removal on the mixed gas, and outputs the dust-removed mixed gas to the high-temperature desulfurization device (5); the temperature of the dust-removed mixed gas is 1070℃-1230℃. The high-temperature desulfurization device (5) is connected to the dust collector (4) and the high-temperature decarbonization device (6). It uses a high-temperature desulfurizing agent to perform desulfurization treatment on the mixed gas after dust removal, reducing the H2S content in the mixed gas, and outputting the desulfurized mixed gas to the high-temperature decarbonization device (6). The high-temperature decarbonization device (6) is connected to the high-temperature desulfurization device (5) and the gas-based vertical furnace (7). It performs decarbonization treatment on the desulfurized mixed gas to reduce the CO2 content in the mixed gas and outputs the decarbonized mixed gas to the gas-based vertical furnace (7). The temperature of the decarbonized mixed gas is 920℃-1080℃. The gas-based vertical shaft furnace (7) contains iron ore and / or oxide pellets, and receives the decarbonized mixed gas input from the high-temperature decarbonization device (6), which reacts to produce sponge iron and the furnace top gas.
2. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to claim 1, characterized in that, The high-temperature decarbonization device (6) is also connected to the conveying device (2) for outputting the decarbonized CO2 into the conveying device (2); The conveying device (2) uses CO2 to feed the raw coal processed by the coal pretreatment device (1) into the gasifier (3).
3. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to claim 1, characterized in that, The operating pressure for preparing syngas in the gasifier (3) is 2.0 MPa-6.5 MPa.
4. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to any one of claims 1-3, characterized in that, The high-temperature desulfurization device (5) uses a desulfurizing agent to perform desulfurization operation at an ambient temperature of 1020℃-1180℃. The desulfurizing agent includes metal oxide and / or composite metal oxide adsorbent particles.
5. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to claim 4, characterized in that, The metal oxide includes at least one of iron oxide, zinc oxide, copper oxide, calcium oxide, and cerium oxide, and the composite metal oxide includes at least one of iron-calcium, copper-manganese, zinc ferrite, and zinc titanate metal oxides.
6. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to any one of claims 1-3, characterized in that, The high-temperature decarbonization device (6) uses a decarbonization agent to perform decarbonization operation, thereby achieving CO2 desorption and capture. The ambient temperature is 970℃-1130℃. The decarbonization agent includes CaO-based and / or Li4SiO4-based adsorbent particles.
7. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to claim 1, characterized in that, The operating pressure inside the gas-based vertical furnace (7) is 1.7MPa-6.2MPa.
8. The system for producing sponge iron by coupling a gasifier and a gas-based vertical shaft furnace according to claim 1, characterized in that, Dust collectors (4) include cyclone dust collectors.