High-speed iron red mud reactive distillation dealkalization carbon fixation and reduction ironmaking unit

Abstract

This invention provides a reactive distillation dealkali removal and carbon fixation device for high-speed ironmaking using red mud, mainly composed of reactive distillation dealkali removal and carbon fixation equipment, fluidized bed reduction reaction magnetic separation equipment, and Y-type gasification furnace in-situ reduction ironmaking equipment. The reactive distillation dealkali removal and carbon fixation equipment is a through-flow tray structure with 1-30 theoretical trays and a tray spacing of 250-900 mm. A red mud slurry distributor is installed at the top of the tower, and a mixed flue gas distributor is installed at the bottom of the tower. The top of the tower is the purified flue gas outlet, and the bottom of the tower is equipped with... There is a dealkali-fixed carbonized red mud outlet; in the fluidized drying-reduction reaction-magnetic separation equipment, the fluidized drying tower is a turbulent fluidized bed, the fluidized reduction reactor is a pulse riser pulverizing reactor, and the magnetic separation is a dry magnetic separator; the upper part of the Y-type flow bed gasification reduction blast furnace is a cylindrical gasification section, and the lower part is a cylindrical settling separator. The top of the gasification section is equipped with top nozzles and side nozzles, and the nozzles are distributed in an inverted Y-shaped structure. The bottom of the settling separator is equipped with a slag outlet, a molten iron outlet, and an emergency treatment outlet.

Description

Technical Field

[0001] This invention provides a device for reactive distillation, dealkali removal, carbon fixation, and reduction ironmaking of high-speed iron red mud, which belongs to the field of environmental protection. Background Technology

[0002] Red mud is a highly alkaline pollutant waste residue discharged during the extraction of alumina in the electrolytic aluminum industry. On average, 1.0 to 2.0 tons of red mud are generated for every ton of alumina produced. Resource utilization is an internationally recognized effective means of utilizing red mud. Although five major utilization technologies have been developed domestically and internationally, namely powder materials, element extraction, cementing materials, road materials, and building ceramics materials, they are all currently in the technological development stage and have not yet been commercialized.

[0003] The high-value utilization of ferrous red mud containing more than 30% iron oxide has been a persistent challenge, primarily due to its excessive sodium oxide content and high content of non-magnetic iron oxide. Red mud is a highly alkaline solid waste with a pH as high as 11-13. The alkaline substances in red mud are mainly of two types: soluble alkali (free alkali) and insoluble alkali (bound alkali). Free alkali mainly includes NaOH, Na₂CO₃, and NaHCO₃. 3、 Insoluble alkalis include NaAl(OH)4, Na2SiO3, etc., and include calcite, nepheline, hydrated garnet, sodalite, and tricalcium aluminate. Nepheline is the main alkali-containing substance, with sodium oxide (Na2O) being the main alkaline oxide in its chemical composition, accounting for up to 12.91%, mainly in the form of caustic soda, sodium aluminate, and sodium aluminosilicate. Soluble alkalis can be removed by CO2 or water washing at normal temperature and pressure, but this part accounts for a small proportion. Most of the alkalis are insoluble, especially in Bayer process red mud, where sodium silicate slag accounts for a large proportion, about 35-45%. The removal of this part of the alkali is one of the most difficult problems to solve globally and a key issue affecting the further large-scale utilization of red mud. In addition, the iron oxides contained in high-iron red mud include not only strongly magnetic magnetite (Fe3O4), but also non-magnetic or weakly magnetic needle-like iron oxide, sodium ferrite, and ferric hydroxide, which directly affect the magnetic separation effect and recovery rate. There is an urgent need for efficient, rapid, and low-cost reduction magnetization technology and equipment.

[0004] Electrolytic aluminum production is a high-energy-consuming and high-polluting industry, and is typically supported by large-scale thermal power plants. These plants process CO2 and SO2 from the flue gas. x and NO x Using acidic gases for red mud dealkali removal can achieve acid-base neutralization and waste-to-waste treatment, while efficiently and cost-effectively solving the two major challenges of red mud dealkali removal and flue gas decarbonization and ultra-low emissions. Alcoa in Western Australia has already extensively applied the CO2 method for dealkali removal, adding gaseous and liquid CO2 to thickened red mud slurry. The CO2 reacts with the alkaline components in the slurry to achieve dealkali removal. However, current methods using gas dispersion by introducing flue gas into the red mud slurry or red mud slurry spraying achieve dealkali removal rates of less than 50%. Furthermore, due to SO2...x Stronger acidity than CO2, it readily reacts with insoluble alkaline substances, significantly improving the dealkali removal rate. However, existing flue gas dealkali removal processes have not yet achieved staged utilization of flue gas, making insoluble alkaline substances a persistent problem in red mud dealkali removal. Therefore, there is an urgent need to develop multiphase flow reactive distillation dealkali removal and carbon fixation technology and equipment for high-speed iron red mud flue gas, as well as its reduction ironmaking process, to overcome the challenges posed by SO2. x This technology addresses industrial bottlenecks such as efficient CO2 utilization based on reactivity, slurry blockage, and efficient dispersion, mass transfer, and reaction, and constructs a high-value utilization industrial chain for high-iron red mud resources, providing a guarantee for the sustainable and high-quality development of the electrolytic aluminum industry. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies for the resource utilization of high-speed iron red mud by proposing a reactive distillation dealkalization, carbon fixation, and reduction ironmaking device for high-speed iron red mud. This device solves the problem of removing insoluble alkaline substances from red mud in a low-cost and efficient manner. At the same time, it solves the problem of high-value utilization of high-speed iron red mud resources by using fluidized bed drying, reduction magnetization, magnetic separation, and in-situ reduction ironmaking in a gas flow bed. In addition, it also realizes the efficient utilization of acidic gases in flue gas according to their reactivity, thus solving the problems of decarbonization and ultra-low emissions of combustion flue gas at high efficiency and low cost.

[0006] The technical solution of the present invention.

[0007] This invention provides a reactive distillation dealkali removal, carbon fixation, and reduction ironmaking device for high-iron red mud. It mainly consists of three processes: reactive distillation dealkali removal and carbon fixation, fluidized bed reduction and magnetic separation, and in-situ reduction ironmaking in a Y-type gasifier. The bottom of the reactive distillation column, connected to a filter press and a mixing mud pump, along with a water washing desalination tower and its brine return line, forms the reactive distillation dealkali removal and carbon fixation process. The high-iron red mud slurry treated by the reactive distillation column has a concentration of 5%-60% by mass, and the spray density within the tower is 5-120 m³ / s. 3 / (m 2•h), the counter-current upward soft water flow velocity in the water washing desalination tower is 0.001-1.5 m / s; the fluidized drying tower, through the top drying gas-solid separator and the bottom reduction tail gas pipeline and its combustion chamber, together with the fluidized reduction reactor and its magnetic separator, forms the fluidized reduction reaction magnetic separation process equipment. The fluidized drying temperature is 100~180℃, the reduction reaction temperature is 700-1300℃, and the purity of the magnetically separated iron ore powder is 40%-95%; the upper part of the Y-type flow bed gasification reduction ironmaking furnace is a cylindrical gasification section, and the lower part is a cylindrical settling separator. The top of the gasification section is equipped with top nozzles and side nozzles, and the nozzles are distributed in an inverted Y-shaped structure. The bottom of the settling separator is equipped with a slag outlet, an iron outlet, and an emergency treatment outlet; the reactive distillation dealkali and carbon fixation process equipment, through the dehydration filter at the bottom of the water washing desalination tower, together with the fluidized bed gas-solid separator, forms the fluidized bed magnetic separation process equipment. The fluidized bed drying tower of the magnetic separation equipment for the reduction reaction is connected to the flue gas distributor at the bottom of the water washing desalination tower through the top drying gas-solid separator; the fluidized bed reactor of the magnetic separation equipment for the reduction reaction is connected to the feed nozzles (top nozzle and side nozzle) of the Y-type fluidized bed gasification reduction blast furnace through the top reduction gas-solid separator, cooler and magnetic separator and its mixing bin; the Y-type fluidized bed gasification reduction blast furnace is connected to the bottom fluidized gas feed pipeline of the fluidized bed reactor of the magnetic separation equipment for the reduction reaction through the ironmaking tail gas outlet of the bottom settling separator, thus forming a circulation system of high-iron red mud reactive distillation dealkalization and carbon fixation and reduction ironmaking.

[0008] The reactive distillation column is a through-flow tray structure with 1-30 theoretical trays and a tray spacing of 250-900 mm. A red mud slurry distributor is installed at the top of the column, and a mixed flue gas distributor is installed at the bottom of the column. The top of the column is the purified flue gas outlet, and the bottom of the column is the dealkalized carbon-fixing red mud outlet.

[0009] The CO2 content in the combustion flue gas is 12%-25%, SO2 content is 25%. x Content ranges from 0-50000 ppm, NO x The content is 0-3000 ppm, and the flow velocity inside the flue gas tower is 0.5-3.0 m / s.

[0010] Water washing desalination towers can be cross-flow plate towers, packed towers, or empty towers.

[0011] The fluidized drying tower is a bubbling fluidized bed, a turbulent fluidized bed, or a riser conveying bed, and the fluidized reduction reactor is a pulse riser reactor, a riser conveying bed, a bubbling fluidized bed, or a turbulent fluidized bed.

[0012] The upper part of the Y-type fluidized bed gasification reduction blast furnace is a cylindrical gasification section, and the lower part is a cylindrical settling separator. The gasification section and settling separator have an inverted T-shaped structure. The gasification section adopts a water-cooled refractory lining layer, and the top is equipped with a downward spray nozzle. There are more than three side nozzles along the circumference in the upper middle part, and the nozzles are distributed in an inverted Y-shaped structure. The side nozzles have an angle of -15° to 15° with the horizontal direction and an angle of -5° to 75° with the radial direction. The settling separator adopts a heat-insulating lining and has a slag outlet, a siphon-type molten iron outlet, and an emergency treatment port at the bottom. The emergency treatment port at the bottom of the settling separator ensures venting in case of shutdown or emergency.

[0013] The oxidant in the Y-type fluidized bed gasification reduction blast furnace is a mixture of water vapor and oxygen, air or oxygen-enriched air with an oxygen content greater than 21%, wherein the volume content of water vapor is 0-40%.

[0014] The features of this invention will be described in detail with reference to the embodiments. Attached Figure Description

[0015] Appendix Figure 1 This is a schematic diagram of the present invention. (See attached diagram.) Figure 1 The drawing is defined as follows:

[0016] 1. Slurry pump 2. Flue gas distributor 3. Reactive distillation column 4. Filter press 5. Mixing slurry pump 6. Water washing and desalination tower 7. Soft water distributor 8. Dehydration filter press 9. Afterburner 10. Fluidized bed dryer 11. Drying gas-solid separator 12. Fluidized reduction reactor 13. Reduction reaction gas-solid separator 14. Cooler 15. Magnetic separator 16. Mixing bin 17. Y-type fluidized bed gasification reduction blast furnace 18. Settling separator 19. Top nozzle 20. Side nozzle 21. Ironmaking tail gas outlet 22. Iron tapping nozzle 23. Slag outlet 24. Emergency treatment port

[0017] A. Purified flue gas B. Washing brine C. Magnetic separation residue D. High-speed iron red mud E. Combustion flue gas F. Soft water G. Pulverized coal H. Air

[0018] The process features of the present invention will be described in detail below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0019] In this embodiment, the high-speed iron red mud reactive distillation dealkalization and carbon fixation and reduction ironmaking unit is mainly divided into three process equipment: reactive distillation dealkalization and carbon fixation, fluidized reduction reaction magnetic separation, and Y-type gasification furnace in-situ reduction ironmaking. The bottom of the reactive distillation tower (3) is connected to the water washing desalination tower (6) and its wash brine return line through a filter press (4) and a mixing mud pump (5) to form the reactive distillation dealkalization and carbon fixation process equipment. The high-speed iron red mud slurry treated by the reactive distillation tower (3) has a concentration of 5%-60% by mass and a spray density of 5-120 m³ / s in the tower.3 / (m 2 •h), the soft water flow velocity in the countercurrent upward of the water washing desalination tower (5) is 0.001-1.5 m / s; the fluidized drying tower (10) is connected to the fluidized reduction reactor (12) and its magnetic separator (15) through the top drying gas-solid separator (11) and the bottom reduction tail gas pipeline and its combustion chamber (9) to form the fluidized reduction reaction magnetic separation process equipment. The fluidized drying temperature is 100~180℃, the reduction reaction temperature is 700-1300℃, and the purity of the magnetically separated iron ore powder is 40%-95%; Y-type fluidized bed gasification reduction ironmaking The upper part of the furnace (17) is a cylindrical gasification section, and the lower part is a cylindrical settling separator (18). The top of the gasification section is equipped with a top nozzle (19) and a side nozzle (20), and the nozzles are distributed in an inverted Y-shaped structure. The bottom of the settling separator (18) is equipped with a slag outlet (23), an iron outlet (22), and an emergency treatment outlet (24). The reactive distillation dealkali and carbon fixation process equipment passes through the dehydration filter (8) at the bottom of the water washing desalination tower (6) and the fluidized reduction reactor. The fluidized drying tower (10) of the magnetic separation process equipment is connected to the flue gas distributor (2) at the bottom of the water washing desalination tower (6) through the top drying gas-solid separator (11); the fluidized reduction reactor (12) of the fluidized reduction process equipment is connected to the feed nozzle (top nozzle (19) and side nozzle (20) of the Y-type flow bed gasification reduction ironmaking furnace (17) through the top reduction reaction gas-solid separator (13), cooler (14) and magnetic separator (15) and its mixing bin (16); the Y-type flow bed gasification reduction ironmaking furnace (17) is connected to the bottom fluidized gas feed pipeline of the fluidized reduction reactor (12) of the fluidized reduction process equipment through the ironmaking tail gas outlet (21) of the bottom settling separator (18), thereby forming a circulating system of high-iron red mud reactive distillation dealkalization carbon fixation and reduction ironmaking.

[0020] The reactive distillation column (3) is a cross-flow structure without downcomers. A red mud slurry distributor is installed at the top of the column. The spacing between the cross-flow trays is 250-900 mm. A combustion flue gas distributor (2) is installed at the bottom of the column. The top of the column is the flue gas outlet, and the bottom of the column is the red mud slurry outlet. The CO2 content in the combustion flue gas is 12%-25%, SO2 content ... x Content ranges from 0-50000 ppm, NO x The content is 0-3000 ppm, and the flow rate of flue gas in the reactive distillation column (3) is 0.5-3.0 m / s.

[0021] The water washing desalination tower (6) is a through-flow plate tower, a packed tower or an empty tower; the fluidized drying tower (10) is a bubbling fluidized bed, a turbulent fluidized bed or a riser conveying bed; and the fluidized reduction reactor (12) is a pulse riser reactor, a riser conveying bed, a bubbling fluidized bed or a turbulent fluidized bed.

[0022] The upper part of the Y-type fluidized bed gasification reduction blast furnace (17) is a cylindrical gasification section, and the lower part is a cylindrical settling separator (18). The gasification section and the settling separator (18) are in an inverted T-shaped structure. The gasification section adopts a water-cooled wall refractory lining layer. A downward spray top nozzle (19) is provided at the top, and more than 3 side nozzles (20) are provided along the circumference in the upper middle part. The nozzles are distributed in an inverted Y-shaped structure. The side nozzles have an angle of -15° to 15° with the horizontal direction and an angle of -5° to 75° with the radial direction. The settling separator (18) adopts a heat-insulating lining. The bottom is provided with a slag outlet (23), a siphon-type iron tapping outlet (22), and an emergency treatment port (24). The top side is provided with an ironmaking tail gas outlet (21), and the emergency treatment port (24) is provided at the bottom of the settling separator to ensure that the gas is vented in case of shutdown or emergency.

[0023] The oxidant of the Y-type fluidized bed gasification reduction blast furnace (17) is a mixture of water vapor and oxygen, air or oxygen-enriched air with more than 21% oxygen, wherein the volume content of water vapor is 0-40%.

[0024] In specific operation, high-iron red mud D at 10-100℃ is sent to the top of the reactive distillation column (3) through a slurry pump (1), and comes into countercurrent contact with mixed flue gas at 30-180℃ introduced from the flue gas distributor (2) at the bottom of the column through a cross-flow tray or packing with 1-30 theoretical plates. The ratio of mixed flue gas to red mud slurry feed is 500~3000:1 (volume ratio). In the reactive distillation column (3), the acidic gases CO2, SOx and NOx in the flue gas react with Na2O, K2O and their alkaline salts in the slurry for efficient reactive distillation. SOx and NOx mainly react with insoluble alkaline substances in the lower part of the column, while CO2 mainly reacts with soluble alkaline substances in the upper part of the column, thereby reducing the pH value of the red mud slurry. The flue gas A is reduced from 11-14 to no more than 8. The purified flue gas A is discharged from the top of the reactive distillation tower (3). The de-alkali and carbon-fixing high-iron red mud slurry flows out from the bottom of the reactive distillation tower (3) and is desalinated by the filter press (4). The dehydrated high-iron red mud slurry is diluted again with some washing brine B and then pumped to the top of the water washing desalination tower (6) by the mixing mud pump (5). It is then washed and desalinated by countercurrent water washing with soft water introduced by the soft water distributor (7). Part of the washing brine B flowing out from the top of the water washing desalination tower (6) is used to dilute the dehydrated red mud slurry and part is mixed with the concentrated brine and sent back to the alumina extraction section. The desalinated red mud slurry flowing out from the bottom of the water washing desalination tower (6) is dehydrated by the dehydration filter press (8) and sent to the fluidized drying tower (10). The reduction tail gas is then added to the water washing desalination tower. After being supplemented by air H in the combustion chamber (9), the gas is also sent to the bottom of the fluidized drying tower (10) for fluidized heating and drying. The dried tail gas obtained by the drying gas-solid separator (11) at the top of the fluidized drying tower (10) is mixed with the combustion flue gas E and sent to the bottom of the reactive distillation tower (3). The dried desalted high-iron red mud obtained by gas-solid separation at the top of the fluidized drying tower (10) is sent to the fluidized reduction reactor (12) and undergoes a reduction magnetization reaction with the reduction ironmaking tail gas at 1300-1700℃. The reduction tail gas obtained by the reduction reaction gas-solid separator (13) at the top of the fluidized reduction reactor (12) is supplemented by combustion and used as the fluidized drying gas of the fluidized drying tower (10). The gas-solid separation at the top of the reduction fluidized reactor (13) is... After being cooled by the reduced red mud cooler (14), the refined iron ore powder is then magnetically separated and recovered by the magnetic separator (15). The refined iron ore powder and coal powder are mixed in the mixing bin (16) and then fed into the Y-type fluidized bed gasification reduction ironmaking furnace (17) with an oxidant. In-situ gasification reduction ironmaking is carried out at 1300-1700℃. The high-temperature molten iron, slag and reduction ironmaking tail gas flow downward into the settling separator (18) at the bottom of the Y-type fluidized bed gasification reduction ironmaking furnace (17). After settling and stratification, molten iron is obtained from the tapping iron outlet (22), slag is obtained from the slag outlet (23) and ironmaking tail gas is obtained from the ironmaking tail gas outlet (21). The ironmaking tail gas is sent back to the fluidized reduction reactor (12), and the molten iron and slag are discharged as products.

[0025] The operation of the Y-type fluidized bed gasification reduction ironmaking furnace (17) involves mixing fine iron ore powder and coal powder at a C:Fe2O3 ratio of 1:1.1-4.0 and feeding them into the mixing bin (16). The iron-coal powder mixture from the mixing bin (16) and the gasifying agent are injected into the gasification section through the top nozzle (19) and the radially inclined side nozzle (20) of the Y-type fluidized bed gasification reduction ironmaking furnace (17), and gasified and reduced at a temperature of 1300-1700℃. The top nozzle (19) and the side nozzle (20) generate multiple jets that collide with each other in the center of the furnace to form a Y-shaped rotating impact high-temperature reaction zone, which ignites each other and strengthens the gasification reduction reaction. The iron coke residue is thrown against the furnace wall of the gasification section and swirls downward. The iron coke residue remains in the gasification section. The reaction time is extended by more than 20 times, and a solidified slag layer is formed on the surface of the refractory layer of the water-cooled wall in the gasification section, so as to achieve slag resistance with slag. The tail gas of ironmaking, high-temperature molten iron and slag flow to the settling separator (18) through the outlet in the center of the conical head of the gasification section. The residual iron ore powder and carbon powder are kept warm and further undergo reduction reaction. The tail gas of ironmaking at 1300-1700℃ is discharged from the tail gas outlet (21) on the top side of the settling separator (18) and is drawn into the fluidized reduction reactor (12) for high-iron red mud reduction magnetization. After the high-temperature molten iron and slag settle and separate, the slag is discharged through the slag outlet, and the high-temperature molten iron is discharged through the siphon-type iron outlet (22) and can maintain a stable iron-slag interface height.

[0026] The reactive distillation dealkali removal, carbon fixation, and reduction ironmaking device for high-iron red mud provided by this invention achieves graded utilization of acidic gases in flue gas according to their reactivity through a reactive distillation tower. This efficiently and cost-effectively solves the problem of removing insoluble alkaline substances from high-iron red mud in a low-cost and efficient manner. The dealkali removal rate is increased from the usual 50% to 98%, and the carbon fixation amount is increased from less than 40 kg CO2 / ton of 30% red mud to more than 150 kg CO2 / ton of 30% red mud. After dealkali removal and carbon fixation, the high-iron red mud is reduced and magnetically separated by ironmaking tail gas and reduced in situ for ironmaking. The purity of iron ore powder is increased by more than 30%, the iron recovery rate is more than 99%, the energy consumption of ironmaking is reduced by more than 50%, and the cost is reduced by 500-1000 yuan / ton of iron, creating conditions for the high-value utilization of high-iron red mud resources.

Claims

1. A high-speed iron red mud reactive distillation dealkalization and carbon fixation and reduction ironmaking unit, characterized by: The high-speed iron red mud reactive distillation dealkalization, carbon fixation, and reduction ironmaking unit mainly consists of three processes: reactive distillation dealkalization and carbon fixation, fluidized bed reduction and magnetic separation, and Y-type gasification furnace in-situ reduction ironmaking. The bottom of the reactive distillation column, via a filter press and a mixing mud pump, connects to a water washing and desalination column and its brine return line, forming the reactive distillation dealkalization and carbon fixation process. The high-speed iron red mud slurry treated by the reactive distillation column has a mass concentration of 5%-60%, and the spray density inside the column is 5-120 m³ / s. 3 / (m 2 •h), the countercurrent upward flow velocity of soft water in the water washing desalination tower is 0.001-1.5m / s; the fluidized drying tower, through the top drying gas-solid separator and the bottom reduction tail gas pipeline and its combustion chamber, together with the fluidized reduction reactor and its magnetic separator, forms the fluidized reduction reaction magnetic separation process equipment. The fluidized drying temperature is 100~180℃, the reduction reaction temperature is 700-1300℃, and the purity of the refined iron ore powder from magnetic separation is 40%-95% (mass); the upper part of the Y-type fluidized bed gasification reduction ironmaking furnace is a cylindrical gasification section, and the lower part is a cylindrical settling separator. The top of the gasification section is equipped with top nozzles and side nozzles, and the nozzles are distributed in an inverted Y-shaped structure. The bottom of the settling separator is equipped with a slag outlet, an iron outlet, and an emergency treatment outlet; the reactive distillation dealkali and carbon fixation process The equipment is connected to the fluidized bed drying tower of the fluidized bed magnetic separation process through the dehydration filter at the bottom of the water washing desalination tower. The fluidized bed drying tower of the fluidized bed magnetic separation process is connected to the flue gas distributor at the bottom of the water washing desalination tower through the top drying gas-solid separator. The fluidized bed magnetic separation process fluidized bed reactor is connected to the top nozzle and side nozzle of the Y-type fluidized bed gasification reduction ironmaking furnace through the top reduction gas-solid separator, cooler, magnetic separator and its mixing bin. The Y-type fluidized bed gasification reduction ironmaking furnace is connected to the bottom fluidized bed gas feed pipeline of the fluidized bed magnetic separation process fluidized bed reactor through the ironmaking tail gas outlet of the bottom settling separator. Thus, a circulating system of high-iron red mud reactive distillation dealkalization and carbon fixation and reduction ironmaking is formed.

2. The high-iron red mud reactive distillation dealkali removal, carbon fixation, and reduction ironmaking apparatus according to claim 1, characterized in that... The reactive distillation column is a cross-flow structure without downcomers. A high-iron red mud slurry distributor is installed at the top of the column. The tray spacing of the cross-flow column is 250-900 mm. A mixed flue gas distributor is installed at the bottom of the column. The top of the column is the purified flue gas outlet, and the bottom of the column is the dealkalized and carbonized red mud slurry outlet.

3. The high-iron red mud reactive distillation dealkali removal, carbon fixation, and reduction ironmaking apparatus according to claim 1, characterized in that... The CO2 content in the combustion flue gas is 12%-25%, SO2 content is 25%. x Content ranges from 0-50000 ppm, NO x The content is 0-3000 ppm, and the flow velocity inside the flue gas tower is 0.5-3.0 m / s.

4. The high-iron red mud reactive distillation dealkali removal, carbon fixation, and reduction ironmaking apparatus according to claim 1, characterized in that... The water washing desalination tower can be a through-flow plate tower, a packed tower, or an empty tower; the fluidized drying tower can be a bubbling fluidized bed, a turbulent fluidized bed, or a riser conveying bed; and the fluidized reduction reactor can be a pulse riser reactor, a riser conveying bed, a bubbling fluidized bed, or a turbulent fluidized bed.

5. The high-iron red mud reactive distillation dealkali removal, carbon fixation, and reduction ironmaking apparatus according to claim 1, characterized in that... The upper part of the Y-type fluidized bed gasification reduction blast furnace is a cylindrical gasification section, and the lower part is a cylindrical settling separator. The gasification section and settling separator have an inverted T-shaped structure. The gasification section adopts a water-cooled refractory lining layer, and the top is equipped with a downward spray nozzle. There are more than three side nozzles along the circumference in the upper middle part, and the nozzles are distributed in an inverted Y-shaped structure. The side nozzles have an angle of -15° to 15° with the horizontal direction and an angle of -5° to 75° with the radial direction. The settling separator adopts a heat-insulating lining and has a slag outlet, a siphon-type molten iron outlet, and an emergency treatment port at the bottom. The emergency treatment port at the bottom of the settling separator ensures venting in case of shutdown or emergency.

6. The high-iron red mud reactive distillation dealkali removal, carbon fixation, and reduction ironmaking apparatus according to claim 1, characterized in that... The oxidant in the Y-type fluidized bed gasification reduction blast furnace is a mixture of water vapor and oxygen, air or oxygen-enriched air with an oxygen content greater than 21%, wherein the volume content of water vapor is 0-40%.

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