Modular shaft furnace system and method for indirect reduction of vanadium titano-magnetite with titanium hydride

Abstract

The application discloses a kind of modular vertical furnace system and method for indirectly reducing vanadium-titanium iron concentrate titanium hydride, and relates to the field of metallurgy, including reaction blast furnace and annular arrangement solid-phase hydrogen storage device, is connected to form integrated hydrogen supply system by hydrogen gas intercommunication device.Connect vanadium-titanium iron concentrate pellets and titanium hydride in vertical furnace and hydrogen storage tank respectively, first hydrogen storage tank is heated to 400-500 DEG C by independent temperature control system to make titanium hydride decompose and release hydrogen, then vertical furnace is heated to 800-1100 DEG C to carry out reduction reaction.Hydrogen released is uniformly injected into reaction zone and ore by annular gas inlet cavity to carry out reduction reaction, and metal iron powder and titanium-containing tailings are obtained by cooling, crushing and magnetic separation after reaction.The application uses solid hydrogen source to avoid gas hydrogen transportation risk, and modular design breaks through the limit of induction heating penetration depth, hydrogen utilization rate of the system reaches more than 84%, iron metallization rate is more than 90%, and green and efficient smelting of vanadium-titanium iron concentrate is realized.

Description

Technical Field

[0001] This invention relates to the field of metallurgical technology, specifically to a modular vertical shaft furnace system and method for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate. Background Technology

[0002] In the smelting of vanadium-titanium iron concentrate, the traditional blast furnace-converter process suffers from low titanium resource utilization, high carbon emissions, and the introduction of impurities due to the use of carbon-based reducing agents. To address these challenges, hydrogen-based reduction technology has received widespread attention as a low-carbon smelting pathway. For example, direct reduction using hydrogen-rich gas in a hydrogen-based shaft furnace, combined with electric furnace smelting, has achieved relatively high-efficiency separation of titanium and carbon emission reduction targets. However, such gaseous hydrogen reduction methods still face inherent difficulties such as high safety risks associated with hydrogen storage and transportation, and complex reaction kinetic control. Existing technologies have also explored processes for direct hydrogen reduction of vanadium-titanium iron concentrate after crushing, but these still rely on external hydrogen sources, and the subsequent fine treatment of the smelting slag for efficient separation of vanadium and titanium is quite complex. Therefore, developing a new method that can avoid the risks of gaseous hydrogen transportation, simplify the process, and achieve more efficient and clean separation of iron, vanadium, and titanium in vanadium-titanium iron concentrate has become an urgent technical problem to be solved in this field.

[0003] Chinese patent CN120119055A discloses an externally heated vertical furnace reaction system for the direct hydrogen reduction of vanadium-titanium iron concentrate. This patent innovatively proposes a method for the direct hydrogen reduction process of vanadium-titanium iron concentrate and the realization of multi-stage gas-phase reforming and recycling of furnace gas, recovering and reusing hydrogen and carbon monoxide gases from the furnace gas tail gas, greatly improving the utilization rate of hydrogen and other gases. However, the method employed in this patent has the problems of easy leakage of hydrogen and other gases, leading to safety issues, and the introduction of other impurities and the generation of harmful gases. Summary of the Invention

[0004] The main objective of this invention is to provide a modular vertical shaft furnace system and method for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate, in order to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides a modular vertical shaft furnace system for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate, comprising: The reaction blast furnace has a preheating section, a reaction section, a cooling section and a discharge section arranged from top to bottom inside. The reaction blast furnace is equipped with a first heating element located in the preheating section and the reaction section. A solid-phase hydrogen storage assembly includes a solid-phase hydrogen storage element arranged circumferentially outside a reaction blast furnace and a second heating element disposed inside the solid-phase hydrogen storage element. The solid-phase hydrogen storage element is provided with a hydrogen gas communication element that communicates with the reaction section. The first heating element and the second heating element are respectively electrically connected to an external temperature control element. The external temperature control element controls the first heating element to heat the solid-phase hydrogen storage element so that the solid-phase hydrogen storage element decomposes into hydrogen gas, which is then transported to the reaction section along the hydrogen gas communication element. The external temperature control element controls the second heating element to heat the materials in the reaction section.

[0006] As a further improvement of the present invention, the temperature control range of the solid-phase hydrogen storage device is 400-500℃, and the temperature control range of the reaction section of the reaction furnace is 800-1100℃.

[0007] As a further improvement of the present invention, the solid-phase hydrogen storage component includes a hydrogen storage tank, an inert permeable filler and a solid-phase hydrogen storage material filled in the hydrogen storage tank, and valves and gas phase sealing ports are provided at the upper and lower ends of the hydrogen storage tank, with the inert permeable filler located in the middle part of the hydrogen storage tank.

[0008] As a further improvement of the present invention, the solid-phase hydrogen storage material is titanium hydride powder or particles, and the inert permeable filler is mixed or layered, wherein the inert permeable filler is zirconia ceramic microspheres.

[0009] As a further improvement of the present invention, the hydrogen communication component includes a hydrogen manifold, and an annular gas inlet chamber communicating with the hydrogen manifold is provided between the heating and storage device and the outer wall of the reaction blast furnace. The annular gas inlet chamber is arranged around the lower part of the reaction section, and the cavity of the annular gas inlet chamber is provided with multiple radially distributed ports along the circumference for uniformly injecting hydrogen into the reaction blast furnace.

[0010] As a further improvement of the present invention, the outer wall of the reaction blast furnace is provided with a circulating furnace gas pipeline, a condenser is provided on the circulating furnace gas pipeline, and a pressure gauge and a valve, a first gas phase conversion device and a dust collector are sequentially provided between the circulating furnace gas pipeline and the condenser. The outlet of the dust collector is connected to the inlet on one side of the condenser. The condenser is provided with an internal baffle. A pressure gauge is provided above the condenser. A condensate outlet is provided below the condenser. A condenser outlet is provided on the other side of the condenser. The condenser outlet is connected to a pressure gauge and a one-way valve. A second gas phase conversion device is provided between the condenser and the reaction blast furnace. The outlet of the second gas phase conversion device is connected to the inlet of the annular gas inlet chamber. A gas flow meter and a temperature sensor are provided between them.

[0011] As a further improvement of the present invention, a stable hydrogen source interface is provided on one side of the barometer and the one-way valve.

[0012] As a further improvement of the present invention, the outer wall of the reaction blast furnace is provided with a composite layered cooling structure outer wall; the cooling structure outer wall includes, from the inside to the outside, a high thermal conductivity inner lining layer in close contact with the furnace wall, a cooling layer with built-in cooling channels, and an outer protective layer.

[0013] As a further improvement of the present invention, the volume ratio of the reaction blast furnace to the solid-phase hydrogen storage device is 1:0.15 to 1:0.2.

[0014] The indirect reduction method of vanadium-titanium iron concentrate with titanium hydride according to the present invention includes the following steps: Vanadium-titanium iron concentrate was prepared into oxide pellets, and titanium hydride and inert permeable filler were packed into a solid-phase hydrogen storage device. The oxidized pellets are added to the preheating section of the vertical furnace for preheating; The solid-phase hydrogen storage device is heated to 400-500℃ by independent control, causing titanium hydride to decompose and release hydrogen gas; Simultaneously, the vertical furnace reaction section is heated to 800-1100℃; The released hydrogen gas is injected into the reaction section through a hydrogen interconnection device to carry out a reduction reaction with the preheated oxidized pellets for 1-3 hours. The reaction product is cooled in the cooling section and discharged through the outlet. It is then crushed, ground and separated by magnetic separation to obtain metallic iron powder and titanium-containing tailings.

[0015] The beneficial effects of this invention are: This invention adopts a modular ring-integrated hydrogen supply system design. Titanium hydride and vanadium-titanium iron concentrate are placed in the blast furnace body and multiple titanium hydride storage tanks, respectively. During the reaction, the solid phase materials are completely separated, and the products after the reaction can be collected separately. This fundamentally solves the problem of iron-titanium alloy formation under mixed charging, simplifies the subsequent separation process, and reduces processing costs.

[0016] This invention employs an independent temperature control system in the heating method, which can precisely control the titanium hydride decomposition temperature between 400-500℃ and the reduction reaction temperature between 800-1100℃, ensuring that the titanium hydride decomposition rate matches the reduction reaction requirements and avoiding waste of reducing agent or incomplete reaction. Hydrogen gas is directly introduced into the main reaction zone of the blast furnace through a hydrogen interconnection device, achieving a hydrogen utilization rate of over 85% and shortening the reduction reaction time by more than 30%.

[0017] This invention uses titanium hydride as a reducing agent. The residual metallic titanium in the sub-furnace is combined with the titanium-containing tailings from the mother furnace product separation, and then regenerated through hydrogenation to produce titanium hydride, which is then returned to the system for recycling. Compared to traditional single-use carbon-based or hydrogen-based reducing agents, the reducing agent consumption cost is reduced by more than 60%, significantly improving economic efficiency. Furthermore, the reduction product is water, with no carbon dioxide emissions, aligning with the direction of green metallurgy development. The entire process achieves a closed-loop cycle of titanium, resulting in high resource utilization and environmental friendliness.

[0018] This invention performs solid-state reduction at a medium-low temperature of 800-1100℃, far lower than the 1500℃ high temperature of traditional blast furnaces, and avoids the high energy consumption in the molten state, improving thermal energy utilization by more than 25%. Furthermore, independent heating via mother and daughter furnaces allows for precise energy supply according to the reaction stage, preventing energy waste. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a modular vertical furnace system for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to the present invention. Figure 2 This is a schematic diagram of the hydrogen communication component of a modular vertical furnace system for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to the present invention. Figure 3 This is a schematic diagram of the overall structure of a solid-phase hydrogen storage device in a modular vertical furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to the present invention. Figure 4 This is a schematic diagram of a single structure of a solid-phase hydrogen storage device for a modular vertical furnace system that indirectly reduces titanium hydride from vanadium-titanium iron concentrate according to the present invention. Explanation of reference numerals in the attached figures: 1. Feeder; 2. Feed hopper; 3. Blast furnace; 301. Preheating section; 302. Reaction section; 303. Cooling section; 304. Discharge section; 4. Heating and storage device; 5. Hydrogen connection component; 6. Cooling structure outer wall; 7. Discharge port; 8. Pressure gauge and valve; 9. First gas phase conversion device; 10. Circulating furnace gas pipeline; 11. Dust collector; 12. Condenser inlet; 13. Internal baffle; 14. Second pressure gauge; 15. Condensate outlet; 16. Condenser outlet; 17. Pressure gauge and one-way valve; 18. Stable hydrogen source interface; 19. Second gas phase conversion device; 20. Gas flow meter and temperature sensor; 21. Solid phase hydrogen storage device; 22. Valve and gas phase sealing port; 23. Solid phase hydrogen storage material; 24. Inert permeable filling material. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the described embodiments are merely some, not all, of the embodiments of this invention. Unless otherwise specified, the embodiments and features described in this application can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0021] In one embodiment, see Figure 1 The present invention discloses a modular vertical furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate, comprising a reaction blast furnace 3 and a solid-phase hydrogen storage component.

[0022] The blast furnace 3 is equipped with a preheating section 301, a reaction section 302, a cooling section 303, and a discharge section 304 arranged sequentially from top to bottom. The blast furnace 3 is equipped with a first heating element located at the preheating section 301 and the reaction section 302. The solid-phase hydrogen storage assembly includes a solid-phase hydrogen storage element arranged circumferentially outside the blast furnace 3 and a second heating element arranged inside the solid-phase hydrogen storage element. The solid-phase hydrogen storage element is equipped with a hydrogen gas communication element 5 that communicates with the reaction section 302. The first heating element and the second heating element are electrically connected to an external temperature control element. The external temperature control element controls the first heating element to heat the solid-phase hydrogen storage element so that the solid-phase hydrogen storage element decomposes into hydrogen gas, which is then transported to the reaction section 302 along the hydrogen gas communication element 5. The external temperature control element controls the second heating element to heat the material in the reaction section 302.

[0023] The first heating element can be selected from different heating methods such as induction heating and resistance heating. However, when using induction heating, more than 40wt% of direct reduced iron products (reduction degree greater than 90%) or metallic iron powder must be mixed in during the initial feeding to ensure that the material heats up quickly during the external heating process. No addition is required after continuous production.

[0024] The second heating element can be selected from different heating methods such as induction heating and resistance heating, just like the first heating element.

[0025] Combination Figure 1 The top of the reaction blast furnace 3 is equipped with a feeder 1 and a feeding bin 2 that are connected to the preheating section 301. The outlet of the feeder 1 is connected to the feeding end of the feeding bin 2. The connection method is flange connection, and the sealing is graphite gasket or metal spiral wound gasket. A level gauge or level switch can be installed at the interface between the feeder 1 and the feeding bin 2 to monitor the level.

[0026] The reactor blast furnace is a vertical furnace with a pressure ranging from atmospheric pressure to 1.5 MPa. The middle section of the outer wall of the reaction blast furnace 3 is connected to a heating and storage device 4, which forms an integrated heating and storage unit with a heating and storage structure. The heating and storage device 4 has space for the installation of a solid-phase hydrogen storage device 21. The core of this unit consists of a hydrogen storage tank, an internal or external heating system, and supporting and mass transfer components.

[0027] The middle section of the vertical shaft furnace's outer wall contains a connected, heavy-duty annular plate or shell, which serves as the main load-bearing structure for the entire unit, supporting the weight of all hydrogen storage tanks and auxiliary components. Each solid-phase hydrogen storage tank corresponds to an independent mounting base with a slot or clamp. This base is typically made of a heat-resistant alloy (such as 310S) and matches the shape of the tank to achieve precise positioning and mechanical fixation.

[0028] The cooling section 303 is externally equipped with a cooling structure outer wall 6, which is a composite layered design. From the inside out, it includes: an inner lining layer, which is in close contact with the outer wall of the blast furnace 3 and is made of a high thermal conductivity and high temperature resistant material to ensure efficient heat removal; a cooling flow channel layer, which has grooves with specific patterns, such as serpentine patterns, machined on the outer wall substrate, and together with the external cooling shell, forms a closed cooling circuit. The cooling medium flows in this circuit to remove heat; and the outermost layer is a protective material covering the cooling shell, used to physically protect the inner material.

[0029] The outer wall of the cooling structure 6 adopts a composite layered design, which aims to achieve efficient thermal management and structural protection for the reaction blast furnace 3; the inner lining layer is closely attached to the outer wall of the blast furnace and is made of high thermal conductivity and high temperature resistant material to ensure efficient heat dissipation; a gradient transition layer can be formed between this layer and the blast furnace wall through a thermal spraying process to reduce contact thermal resistance and prevent local overheating.

[0030] After the cooling section 303, there is a discharge port 7 for discharging the reduced material. The size of the discharge port 7 is determined according to the processing capacity and material flowability, and is usually a round or square opening. A discharge valve is installed at the discharge port 7. The discharge valve is a star feed valve, a slide gate valve or a rotary valve, selected according to the material characteristics and sealing requirements.

[0031] In a preferred embodiment, the serpentine (reciprocating) flow channel is composed of multiple axially extending parallel grooves machined on the substrate of the outer wall 6 of the cooling structure, and circumferentially extending connecting grooves connecting the ends of these parallel grooves, which are alternately connected. The cooling medium flows repeatedly in the axial direction in this closed loop, and its flow path covers the entire wall area to be cooled.

[0032] In a preferred embodiment, the cooling medium is preferably water, more preferably treated deionized water or circulating cooling water with added corrosion inhibitors and scale inhibitors.

[0033] In a preferred embodiment, the high thermal conductivity and high temperature resistant material is preferably graphite or other high temperature resistant materials with excellent thermal conductivity and thermal stability.

[0034] The preheating section 301 has a height that accounts for 1 / 3–1 / 2 of the total height of the reaction blast furnace 3, and its diameter is 1.2–1.5 times the diameter of the furnace belly. The hydrogen injection pressure is maintained at 0.2–0.5 MPa to ensure that the gas flow penetrates the material layer. The refractory lining thickness is 200–400 mm, and the heat-absorbing guide plate is made of heat-resistant alloy (such as 310S stainless steel) with a through hole diameter of 5–15 mm.

[0035] In the preferred embodiment, the system pressure originates primarily from the thermal decomposition reaction of the solid-phase hydrogen storage material 23 within the solid-phase hydrogen storage device 21. The independent temperature control system precisely controls the reaction temperature of the solid-phase hydrogen storage device 21 within a set range of 400-500°C. At this temperature, the rate of hydrogen production from the decomposition of titanium hydride is controllable and stable. The gas accumulation generated in the closed or semi-closed container constitutes the initial pressure source required by the system. By adjusting the heating power, the gas production rate can be directly and linearly controlled, thus establishing a foundation for pressure stability.

[0036] In the preferred embodiment, the feeder 1 can be a rotary feeder valve or a screw feeder, and the feed hopper 2 can be a combination design of an upper cylinder and a lower cone hopper. The cone angle of the cone hopper is optimized, and the half cone angle of the cone hopper must be greater than the angle of repose of the material by more than 10-15 degrees to ensure that the material slides down smoothly by gravity and prevents bridging or arching.

[0037] In the preferred embodiment, the outer wall of the reaction blast furnace 3 adopts a composite layered design, which includes a refractory lining, a cooling layer, a pressure-bearing shell, and an insulation layer from the inside out. The main body of the outer wall of the reaction blast furnace 3 is a cylindrical structure, with the top connected to the furnace throat and the bottom fixed to the hearth flange. Multiple hydrogen injection ports are opened circumferentially on the middle section side wall. The middle section outer wall is connected to the titanium hydride storage tank through a ring-shaped pipeline to form an integrated hydrogen supply system.

[0038] Further, see Figure 1 , 3 4. The solid-phase hydrogen storage device includes a hydrogen storage tank, an inert permeable filler 24 filled in the hydrogen storage tank, and a solid-phase hydrogen storage material 23. The upper and lower ends of the hydrogen storage tank are equipped with valves and gas phase sealing ports 22. The inert permeable filler 24 is located in the middle part of the hydrogen storage tank and is used to improve the heat transfer performance of the bed, maintain the unobstructed gas passage, and prevent the hydrogen storage material from pulverizing and agglomerating. There are gaps between the inert permeable fillers 24 to be filled with solid-phase hydrogen storage material 23 (such as titanium hydride powder or granules) for storing the hydrogen required for the reaction. A barometer is provided on the outside of the device to monitor the internal gas pressure.

[0039] In the preferred embodiment, the valve adopts a lift-type ball valve or a cone plug valve structure; the gas phase seal port is a precision-machined interface at the valve inlet end, and its core feature is the integration of multiple sealing structures.

[0040] In a preferred embodiment, the inert and breathable filler 24 is made of an inert material with high hardness and high chemical stability; the material is zirconia (ZrO2) ceramic microspheres.

[0041] In the preferred embodiment, the solid-phase hydrogen storage material 23 is primarily titanium hydride (TiH2) powder or particles; its theoretical basis is that titanium hydride decomposes to release hydrogen gas upon heating, with the reaction formula being TiH2→ Ti + H2↑. This material exhibits high volumetric hydrogen storage density and excellent thermal stability in solid-state hydrogen storage applications. Compared to other materials, titanium hydride has a relatively high decomposition temperature, making it highly suitable for coupling with high-temperature industrial processes such as blast furnaces, facilitating the utilization of waste heat from the process.

[0042] Further, see Figure 1 , 2 The hydrogen connection component 5 includes a hydrogen manifold. An annular inlet chamber connected to the hydrogen manifold is provided between the heating and storage device 4 and the outer wall of the blast furnace 3. The annular inlet chamber is used to provide space for the flow of reducing gas. The annular inlet chamber is designed as a closed loop around the reactor or main pipeline. The cross-sectional area of ​​the chamber can be adjusted circumferentially. At the same time, the chamber is provided with multiple radially distributed ports circumferentially to uniformly introduce the gas into the subsequent reaction area or merge with other pipelines.

[0043] In one embodiment, see Figure 1 A furnace gas circulation system is also provided. A circulating furnace gas pipeline 10 is installed on the outer wall of the reaction blast furnace 3. A condenser is installed on the circulating furnace gas pipeline 10. The circulating furnace gas pipeline 10 is located in the upper middle part of the furnace body and exits from the furnace body. Between the circulating furnace gas pipeline 10 and the condenser, a pressure gauge and valve 8, a first gas phase conversion device 9, and a dust collector 11 are sequentially installed. The pressure gauge and valve 8 are used to control and regulate the gas pressure and flow rate in the pipeline. The first gas phase conversion device 9 is used for gas phase conversion, converting the added carbon powder and water vapor present in the furnace gas into hydrogen and reducing carbon monoxide. The dust collector 11 captures dust particles in the furnace gas, achieving gas purification or dust recovery. The outlet of the dust collector 11 is connected to the condenser inlet 12. The condenser has an internal baffle 13 to change the fluid flow path, enhance heat transfer efficiency, and support the heat exchange tube bundle. Above the condenser... A second pressure gauge 14 is provided to monitor the internal pressure of the condenser; a condensate outlet 15 is provided below the condenser to discharge condensate; a condenser outlet 16 is provided on the other side of the condenser, and the condenser outlet 16 is connected to a pressure gauge and a one-way valve 17 to monitor and control the output gas pressure and flow rate of the condenser; a stable hydrogen source interface 18 is provided on one side of the pressure gauge and the one-way valve for connecting a stable hydrogen source in special circumstances; a second gas phase conversion device 19 is provided after the stable hydrogen source branch merges with the main gas collecting pipeline for gas phase conversion, which converts the residual water vapor back into hydrogen and reducing carbon monoxide to ensure that the gas is dry and free of water vapor; the outlet of the second gas phase conversion device 19 is connected to the inlet of the annular gas inlet chamber, and a gas flow meter and a temperature sensor 20 are provided between them to monitor the temperature and flow rate of the gas entering the furnace.

[0044] The barometer and valve unit 8 comprises several barometers and several valves, forming an integrated pressure monitoring and regulation unit. This unit monitors pressure changes within pipelines or containers in real time and controls the opening and closing of valves accordingly, aiming to achieve dynamic balance and safe control of the internal pressure of the system.

[0045] In the preferred embodiment, the first gas phase conversion device 9 and the second gas phase conversion device 19 include a cylindrical reactor body that is resistant to high temperature and high pressure. The reactor body is provided with a gas inlet, a gas outlet, a catalyst loading / maintenance port, and necessary monitoring instrument interfaces. The gas inlet is connected to the pipeline after the circulating furnace gas pipeline 10 and / or the supplementary hydrogen pipeline merge, and the gas outlet is connected to the purification and conveying system leading to the blast furnace.

[0046] In the preferred embodiment, the circulating gas pipeline 10 connects the gas outlet at the top of the blast furnace 3 with the gas inlet ring pipe at the bottom of the furnace body, forming a closed gas circulation path. To achieve flexible layout, the pipeline can be laid three-dimensionally according to the site space, and some sections can extend along the outer wall of the existing reaction tower or dust removal equipment, utilizing the support structure of the main equipment.

[0047] The dust collector 11 can preferably be a combined design that integrates cyclone separation and filtration dust removal. For example, it can include a cyclone dust collector 11 as a primary treatment and a bag filter dust collection assembly as a fine treatment.

[0048] In the preferred embodiment, the body of the stable hydrogen source interface 18 is typically made of a hydrogen-compatible metal material such as stainless steel, and is equipped with a quick-connect coupling or flange connection as standard. For example, a quick-connect coupling for hydrogen conforming to GB / T 26779-2011 or other applicable standards can be selected to ensure quick and airtight connection and disconnection with the external hydrogen source pipeline. A one-way valve can be integrated inside the interface to prevent hydrogen backflow.

[0049] In a preferred embodiment, the gas flow meter and temperature sensor 20 may be gas flow fiber optic grating sensors or other flow meters, and the temperature sensor may be chip-type integrated or other temperature sensors.

[0050] In this embodiment, vanadium-titanium iron concentrate is crushed and ground to a particle size of ≤0.074mm accounting for more than 80%, and then pressed into pellets; titanium hydride powder is prepared separately with a particle size of 1-100μm and a purity of ≥98%; the two materials are stored separately for later use.

[0051] The prepared vanadium-titanium iron concentrate is placed in a hopper. Titanium hydride powder or granules are then filled into a cylindrical hydrogen storage tank. The hydrogen storage tank is connected to the blast furnace via a hydrogen connection pipe, but the solid materials remain physically separated. The hydrogen storage tank is heated to 400-500℃ at a heating rate of 5-15℃ / min and held for 0.5-1 hour to allow the titanium hydride in the tank to fully decompose. The released hydrogen enters the reaction zone through the connection pipe. Subsequently, the blast furnace is heated to 800-1100℃ and held for 1-3 hours to allow the hydrogen to react with the vanadium-titanium iron concentrate to produce metallic iron and titanium oxides.

[0052] In an optional implementation, the system adopts a modular reactor design, consisting of a reaction blast furnace 3 and multiple titanium hydride hydrogen storage tank decomposition reactors; these hydrogen storage tank reactors are arranged in a ring array around the reaction blast furnace 3, forming an integrated hydrogen supply system.

[0053] In an optional embodiment, the reaction blast furnace 3 is connected to multiple titanium hydride hydrogen storage tanks via a hydrogen connecting pipe. Valves or baffles are provided at both ends of the hydrogen connecting pipe to control the gas flow.

[0054] In an optional implementation, the hydrogen connector is made of high-temperature resistant stainless steel or nickel-based alloy, capable of withstanding operating temperatures of 300-1100°C.

[0055] In an optional embodiment, the main body of the reaction blast furnace 3 and the multiple titanium hydride hydrogen storage tanks are respectively equipped with independent heating systems, temperature control systems and pressure monitoring systems. The heating of the main body of the reaction blast furnace 3 and the multiple titanium hydride hydrogen storage tanks adopts an independent temperature control system. The sub-furnace is first heated to 400-500℃ to decompose titanium hydride, and the main furnace is simultaneously or slightly heated to 800-1100℃ to carry out the reduction reaction.

[0056] In an optional embodiment, the top of the blast furnace body is integrated with an exhaust port, a feed port, a discharge port, and a pressure regulating device; the titanium hydride storage tank adopts a detachable modular structure and is connected to the gas supply system through a standardized interface.

[0057] In an optional embodiment, the hydrogen manifold is provided with an equal number of gas flow channels as the number of titanium hydride storage tanks. The channel diameter is 50-200 mm, and the length is determined according to the furnace body spacing. Porous baffles or gas distributors can be installed in the channels to improve hydrogen distribution.

[0058] In an optional embodiment, the volume ratio of the reaction blast furnace 3 to the plurality of titanium hydride hydrogen storage tanks is 1:0.15 to 1:0.2, determined according to the stoichiometric ratio of titanium hydride to ore.

[0059] After the reaction is completed, the reduction products in the reaction blast furnace 3 are cooled to room temperature, crushed and ground to a particle size ≤0.074mm, and then separated by magnetic separation to obtain metallic iron powder and titanium-containing tailings; the metallic titanium or unreacted titanium hydride remaining in the sub-furnace is collected separately.

[0060] This invention also provides a modular induction heating vertical furnace reaction method for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate, which employs the aforementioned modular induction heating vertical furnace reaction system and proceeds according to the following steps: Step 1: The solid hydrogen storage material 23, preferably titanium hydride (TiH2) powder or granules, is mixed with the inert permeable filler 24 in a predetermined ratio or layered and filled into multiple solid hydrogen storage devices 21. After sealing, it is connected to the valve through pipes to form a modular hydrogen supply array arranged in a ring around the main body of the blast furnace shaft furnace.

[0061] The vanadium in the vanadium-titanium iron concentrate (the particle size of the vanadium-titanium iron concentrate before pelletizing is ≤0.074mm), 0%~6% (such as 0%, 1%, 2%, 3%, 4%, 5% or 6% etc.) of the vanadium-titanium iron concentrate pellet material, and the direct reduced iron product or metallic iron powder with a reduction degree greater than 90% added as needed (the amount added during the first start-up shall not be less than 40wt% of the total material) are mixed evenly and prepared through the feed hopper 2 and the feeder 1.

[0062] Step 2: Start the first heating element in the heating storage device 4 to preheat the preheating section 301 and reaction section 302 of the vertical furnace of the reaction blast furnace 3; if induction heating is used, the premixed metal components in the furnace charge are used as induction heating elements to quickly raise the furnace temperature to the predetermined range.

[0063] The second heating element inside the solid-phase hydrogen storage device 21 is activated, causing the internal titanium hydride material to slowly heat up to the temperature range where hydrogen begins to be released. The pressure change inside the tank is monitored using a barometer.

[0064] Once the temperature of the preheating section 301 of the reaction blast furnace 3 reaches the set value, for example, above 600°C, the feeder 1 is started to add the mixed furnace charge from the feed bin 2 into the reaction blast furnace 3 at a controllable rate.

[0065] Step 3: The furnace charge moves downward in the reaction blast furnace 3, passing through the preheating section 301 and the reaction section 302 in sequence; in the reaction section 302, the furnace charge is heated to the high temperature required for the reduction reaction, for example, 1100℃-1300℃.

[0066] The heating power of the solid-phase hydrogen storage device 21 is synchronously controlled to decompose titanium hydride and release hydrogen. The released hydrogen is controlled by valves and gas phase seals, transported through hydrogen pipelines, and merged with the circulating coal gas from the circulating furnace gas pipeline 10 before or inside the first gas phase conversion device 9.

[0067] The combined gases enter the first gas phase conversion device 9, where, under the action of a catalyst, the water vapor and carbonaceous components (from coke gasification or circulating coal gas) in the gas are mainly converted into hydrogen and carbon monoxide, thereby achieving the regulation and enrichment of the reducing gas components.

[0068] After conversion and purification (dust removal by dust collector 11 and moisture removal by condenser), the high-temperature reducing gas is metered and monitored by gas flow meter and temperature sensor 20, and is evenly injected into the lower part of the reaction section 302 of the reaction furnace 3 through the annular gas inlet and its radial distribution port, where it undergoes a countercurrent gas-solid reduction reaction with the downward moving vanadium-titanium iron concentrate.

[0069] Step 4: The high-temperature top gas generated by the reaction is discharged from the top of the reaction blast furnace 3, and a portion of it is drawn out as circulating gas through the circulating furnace gas pipeline 10; the amount of circulating gas is controlled by a pressure gauge and valves.

[0070] The extracted circulating coal gas undergoes gas phase conversion, dust removal, condensation and dehydration processes in sequence, mixes with fresh hydrogen supplied by the solid phase hydrogen storage device 21, and re-enters the annular inlet chamber to achieve the recycling of reducing gas.

[0071] The system monitors gas flow, temperature, and pressure at key nodes in real time using gas flow meters, temperature sensors 20, pressure gauges, and a total gas flow meter. By adjusting feed rate, heating power, and gas valve opening, the system maintains stable operation under optimized process parameters. When needed, an external hydrogen source can be quickly connected via a stable hydrogen source interface 18 for supplementation or adjustment.

[0072] Step 5: The metallized charge that has been reduced enters the cooling section 303 at the bottom of the reaction blast furnace 3 and is cooled by the cooling medium on the outer wall 6 of the cooling structure.

[0073] The cooled product is discharged from the system in a controlled manner through outlet 7, completing the smelting process.

[0074] Example 1 The main body of the reaction blast furnace 3 was hoisted to the predetermined position and the foundation was fixed. The furnace body adopts a composite layered outer wall design, which includes a refractory lining, a cooling channel layer, and a protective layer from the inside out. Multiple solid-phase hydrogen storage devices 21 are arranged in a ring array around the main body of the blast furnace shaft. Each hydrogen storage tank is independently fixed by a bracket and connected to the main hydrogen supply pipeline through a pipe with a gas phase sealing port. This arrangement aims to shorten the hydrogen supply path and utilize the waste heat of the furnace body.

[0075] Connect the outlet of the feed hopper 2 to the inlet of the feeder 1 via a flange, and use graphite gaskets or metal spiral wound gaskets to ensure a seal; the outlet of the feeder 1 is connected to the feed port at the top of the preheating section 301 of the reaction blast furnace 3, and a material level monitoring device is installed.

[0076] One end of the circulating furnace gas pipeline 10 is connected to the gas outlet at the top of the reaction blast furnace 3, and the other end is connected in sequence to the first gas phase conversion device 9, the dust collector 11 and the condenser; the condenser outlet 16 is connected to the annular gas inlet chamber through a pipeline. The annular gas inlet chamber is arranged around the lower part of the reaction section 302 of the reaction blast furnace 3. The chamber is provided with multiple radially distributed ports around its circumference to ensure that the reducing gas is uniformly injected into the furnace; the stable hydrogen source interface 18 serves as a backup gas source interface and is connected in parallel to the main hydrogen supply pipeline through a pipeline with a one-way valve.

[0077] The signal cables of each barometer, gas flow meter, and temperature sensor 20, as well as the control cables of each valve actuator, are laid together in the central control room and connected to the PLC to complete the hardware connection of the entire detection and control system.

[0078] Step 1 selects vanadium-titanium magnetite concentrate with a chemical composition of 55wt% TFe, 12wt% TiO2, and 0.8wt% V2O5. After pelletizing, the pellet size is 10-15mm and the compressive strength is ≥2000N / pelle.

[0079] Titanium hydride (TiH2) powder (particle size 0.1–0.5 mm) and zirconia ceramic microspheres (particle size 0.6–0.8 mm) were mixed at a mass ratio of 7:3 and packed into the solid-phase hydrogen storage device 21.

[0080] Step 2: Pellets are added into the reaction blast furnace 3 at a rate of 0.5t / h via feeder 1; the preheating section 301 is heated to 800℃ by induction heating (residence time 15min) to evaporate the moisture from the pellets and preheat them.

[0081] Step 3: Start the heating system of solid-phase hydrogen storage device 21 to decompose titanium hydride at 400°C and release hydrogen gas. The hydrogen gas is injected into reaction section 302 through an annular inlet chamber at a pressure of 0.3 MPa.

[0082] In step four, the temperature of reaction section 302 is maintained at 1000℃, the reduction time is 2h, and the total hydrogen flow rate is calculated according to the formula 0.45×100x×(60 / t0) (x=55, t0=120min). The actual hydrogen supply is 1400L / kg ore.

[0083] Actual results: The iron metallization rate of the reduced pellets reached 86%, and titanium was mainly enriched in the slag phase in the form of TiO2. Through the reforming of the circulating furnace gas by the first gas phase conversion device 9 and the second gas phase conversion device 19, the hydrogen utilization rate was increased to 84%, and the carbon emissions were reduced by 70% compared with the traditional carbon reduction process.

[0084] Example 2 The difference between this embodiment and Embodiment 1 is that the effective volume is increased to 15m³. 3 Six hydrogen storage tanks (each with a volume of 1.2 m³) are arranged in a ring around the blast furnace.

[0085] The selected vanadium-titanium iron concentrate pellets have the following chemical composition: 56wt% TFe, 12.5wt% TiO2, and 0.8wt% V2O5. The pellet size is 10–15 mm, and the compressive strength is ≥2000 N / pellet.

[0086] Other operating steps are the same as in Example 1. Actual results: the iron metallization rate of the reduced pellets reached 88%, and the hydrogen utilization rate was 85%.

[0087] The first gas phase conversion device 9 and the second gas phase conversion device 19 convert residual water vapor and carbon powder into reducing gas, reducing coke consumption by 30%; the composite layer design of the outer wall 6 of the cooling structure ensures that the furnace wall temperature gradient is ≤5℃, avoiding local overheating.

[0088] Example 3 The difference between this embodiment and embodiment 2 is that when the hydrogen production rate of the hydrogen storage tank decreases by 20% due to fatigue of the solid hydrogen storage material 23, the system maintains stability through the following measures: backup hydrogen source access: open the stable hydrogen source interface 18 and supplement external hydrogen to 25% of the total flow rate.

[0089] Enhanced gas-phase reforming: The amount of carbon powder added to the second gas-phase conversion device 19 is increased to maintain the H2 / CO ratio at 2.5:1, ensuring a stable reducing atmosphere. The temperature of reaction section 302 is increased by 50°C through an induction heating system to compensate for the reduction kinetic delay caused by insufficient hydrogen.

[0090] Actual results: Metallization rate fluctuation <4%, and the system recovered to the set process parameters within 30 minutes.

[0091] Example 4 The difference between this embodiment and Embodiment 2 is that when the barometer detects that the pressure inside the hydrogen storage tank is stable and no longer rising, it indicates that the titanium hydride has been fully decomposed and the solid products inside the tank are mainly metallic titanium. After heating is stopped and the tank is cooled down, the hydrogen storage tank can be opened for residue inspection or subsequent processing.

[0092] The dehydrogenated titanium metal residue is retained in a hydrogen storage tank or collected and transferred to a specialized hydrogenation reaction device. Under certain temperature (e.g., 400-600℃) and hydrogen pressure (e.g., 0.1-1.0 MPa), titanium and hydrogen re-react to generate titanium hydride (Ti + H2). TiH2).

[0093] Actual results: Titanium hydride has a hydrogen repetition rate of over 92% and a metallization rate fluctuation of <2%.

[0094] This invention significantly improves production scale through modular vertical furnace integrated control and effectively enhances hydrogen utilization and reduction efficiency by applying furnace gas reforming and gas purification technologies. Specifically, the beneficial effects of this invention include at least the following aspects: By modularly arranging multiple induction-heated vertical shaft furnaces in a compact, honeycomb-like configuration and supplementing them with a central integrated control system, a highly integrated reactor array is constructed. This design physically overcomes the limitation of a single induction heating device on the depth of ore heating penetration, and through the scale-addition effect, the overall processing capacity of the system is increased by orders of magnitude. Taking four sets of honeycomb modular vertical shaft furnaces (a total of 24 furnace units) as an example, its annual processing capacity of vanadium-titanium iron concentrate can reach approximately 100,000 tons, providing an efficient equipment foundation for the industrial application of hydrogen-based smelting of vanadium-titanium magnetite.

[0095] The system combines the modular hydrogen supply of the solid-phase hydrogen storage device 21, the recovery of circulating furnace gas, and the reforming functions of the first gas phase conversion device 9 and the second gas phase conversion device 19. It can not only supply high-purity hydrogen on demand and stably, but also catalytically reform the circulating furnace gas generated by the process, converting components such as CO2 and H2O into effective reducing gases (H2 and CO), and purifying them through dust collection, condensation and other steps. This closed-loop design greatly improves the utilization efficiency of hydrogen and carbon elements, reduces the consumption of reducing agent, and ensures the stability and optimization of the reducing gas composition, thereby strengthening the reduction process of vanadium-titanium iron concentrate.

[0096] The modular solid-phase hydrogen storage device 21 and the reaction blast furnace 3 are designed as a single unit, supporting online isolation, maintenance, or replacement of some units without affecting the operation of the entire system, ensuring the continuity and safety of production. The integrated control system can precisely control the parameters of the entire process, such as feeding, heating, gas supply, and cooling, so that the system operates under optimal conditions. At the same time, this design makes full use of the waste heat and by-product gases from the reaction, significantly reducing energy and material consumption, and combining good operational flexibility with outstanding economic benefits, providing a competitive technical solution for green and low-carbon metallurgy.

[0097] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A modular vertical shaft furnace system for the indirect reduction of titanium hydride from vanadium-titanium iron concentrate, characterized in that, include: The reaction blast furnace (3) has a preheating section (301), a reaction section (302), a cooling section (303) and a discharge section (304) arranged from top to bottom inside. The reaction blast furnace (3) is equipped with a first heating element located in the preheating section (301) and the reaction section (302). The solid-phase hydrogen storage assembly includes a solid-phase hydrogen storage element arranged circumferentially outside the reaction blast furnace (3) and a second heating element arranged inside the solid-phase hydrogen storage element. The solid-phase hydrogen storage element is provided with a hydrogen gas communication element (5) that communicates with the reaction section (302). The first heating element and the second heating element are respectively electrically connected to an external temperature control element. The external temperature control element controls the first heating element to heat the solid-phase hydrogen storage element so that the solid-phase hydrogen storage element decomposes into hydrogen gas and is transported to the reaction section (302) along the hydrogen gas communication element (5). The external temperature control element controls the second heating element to heat the material in the reaction section (302).

2. The modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 1, characterized in that: The temperature control range of the solid-phase hydrogen storage device (21) is 400-500℃, and the temperature control range of the reaction section (302) of the reaction furnace (3) is 800-1100℃.

3. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 2, characterized in that: The solid-phase hydrogen storage component includes a hydrogen storage tank, an inert permeable filler (24) filled in the hydrogen storage tank, and a solid-phase hydrogen storage material (23). The upper and lower ends of the hydrogen storage tank are equipped with valves and gas phase sealing ports, and the inert permeable filler (24) is located in the middle part of the hydrogen storage tank.

4. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 3, characterized in that: The solid-phase hydrogen storage material (23) is titanium hydride powder or particles, and the inert permeable filler (24) is mixed or layered, and the inert permeable filler (24) is zirconia ceramic microspheres.

5. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 4, characterized in that: The hydrogen communication component (5) includes a hydrogen connection pipe. An annular gas inlet chamber connected to the hydrogen connection pipe is provided between the heating and storage device (4) and the outer wall of the reaction blast furnace (3). The annular gas inlet chamber is arranged around the lower part of the reaction section (302). The cavity of the annular gas inlet chamber is provided with multiple radially distributed ports along the circumference for uniformly injecting hydrogen into the reaction blast furnace (3).

6. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 5, characterized in that: The outer wall of the reaction blast furnace (3) is provided with a circulating furnace gas pipeline (10), and a condenser is provided on the circulating furnace gas pipeline (10). Between the circulating furnace gas pipeline (10) and the condenser, a pressure gauge and a valve (8), a first gas phase conversion device (9), and a dust collector (11) are provided in sequence. The outlet of the dust collector (11) is connected to the inlet on one side of the condenser. An internal baffle (13) is provided inside the condenser. A pressure gauge is provided above the condenser. A condensate outlet (15) is provided below the condenser. A condenser outlet (16) is provided on the other side of the condenser. A pressure gauge and a one-way valve are connected to the condenser outlet (16). A second gas phase conversion device (19) is provided between the condenser and the reaction blast furnace (3). The outlet of the second gas phase conversion device (19) is connected to the inlet of the annular gas inlet chamber. A gas flow meter and a temperature sensor (20) are provided between them.

7. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 6, characterized in that: The barometer and one-way valve are equipped with a stable hydrogen source interface (18).

8. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 7, characterized in that: The outer wall of the reaction blast furnace (3) is provided with a composite layered cooling structure outer wall (6); the cooling structure outer wall (6) includes, from the inside to the outside, a high thermal conductivity inner lining layer that is in close contact with the furnace wall, a cooling layer with built-in cooling channels, and an outer protective layer.

9. A modular vertical shaft furnace system for indirect reduction of titanium hydride from vanadium-titanium iron concentrate according to claim 8, characterized in that: The volume ratio of the reaction blast furnace (3) to the solid-phase hydrogen storage device (21) is 1:0.15 to 1:0.

2.

10. The indirect reduction method of titanium hydride from vanadium-titanium iron concentrate according to any one of claims 1-9, comprising the following steps: Vanadium-titanium iron concentrate was prepared into oxide pellets, and titanium hydride and inert permeable filler (24) were loaded into a solid-phase hydrogen storage device (21). The oxidized pellets are added to the preheating section (301) of the vertical furnace for preheating; The solid-phase hydrogen storage device (21) is heated independently to 400-500°C, causing titanium hydride to decompose and release hydrogen. Simultaneously, the vertical furnace reaction section (302) is heated to 800-1100℃; The released hydrogen gas is injected into the reaction section (302) through the hydrogen gas connection device to carry out a reduction reaction with the preheated oxidized pellets for 1-3 hours; The product after reaction is cooled in the cooling section (303) and discharged through the outlet (7). It is then crushed, ground and separated by magnetic separation to obtain metallic iron powder and titanium-containing tailings.

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