A multi-point distribution device and method for a flash reduction iron / steel furnace and a smelting furnace

Abstract

The present application belongs to the field of metallurgy, and particularly relates to a multi-point distribution device and method for a flash reduction iron / steel furnace and a smelting furnace. The distribution device comprises a stock bin, a pressure equalizing tank, a blowing tank, a plurality of material conveying pipes and nozzles. The stock bin is connected to the pressure equalizing tank through a valve, and the pressure equalizing tank is connected to the blowing tank through a valve. The blowing tank is a hollow cavity, and the blowing tank is connected to the initial ends of the plurality of material conveying pipes. The terminal ends of the material conveying pipes are connected to the nozzles. A carrier gas pipe is connected to the blowing tank. The present application can realize high dispersion and uniform distribution of the furnace charge on the cross section of the furnace hearth by rational distribution of the plurality of nozzles on the furnace wall and in combination with an independent material distribution air system, thereby avoiding local accumulation and creating optimal initial conditions for efficient and uniform flash reaction.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical technology, specifically relating to a multi-point charging device and method for flash reduction ironmaking / steelmaking furnaces and a smelting furnace. Background Technology

[0002] In non-blast furnace ironmaking, especially in flash ironmaking, good charge distribution means higher reaction efficiency and better utilization of furnace space. In co-current flash smelting, the material immediately enters the high-temperature zone or combustion zone after entering the furnace space, and traditional charge distribution mechanisms are difficult to adapt to such a harsh high-temperature erosion environment. Iron ore powder has a high density, the reduction reaction is a strongly endothermic process, and the molten iron product is extremely prone to adhering to and forming nodules with refractory materials.

[0003] While mature concentrate nozzles used in copper flash smelting can resist erosion through special design, their complex structure and relatively fixed material coverage area make them unsuitable for various furnace types and production capacities. Existing center-jet charging nozzles based on copper smelting designs (such as CN220335266U and CN101809175A) exhibit several incompatibilities when directly applied to iron ore powder: First, high-density iron ore powder has high inertia, making it difficult to be effectively dispersed by the airflow, resulting in uneven mixing of the material and the reducing gas flow, leading to low reaction rates and reduction efficiency. Second, the concentrated material flow and high localized heat load make it highly susceptible to premature molten iron formation due to improper temperature control, leading to fatal "nodulation" phenomena near the nozzle or on the reaction tower wall, seriously threatening production continuity and safety. Furthermore, these charging nozzles have complex structures, resulting in high manufacturing and maintenance costs. They are also primarily suitable for atmospheric pressure environments and cannot meet the operating requirements of high-pressure flash iron / steelmaking furnaces.

[0004] Therefore, a feeding device is needed that can feed material at multiple points, flexibly adapt to different furnace types with different production capacities, and has a simple structure and is resistant to ablation. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a flash reduction iron / steelmaking furnace charging device and method, as well as a smelting furnace. This invention enables multi-point charging, flexibly adapting to different furnace types with varying production capacities, and possesses advantages such as simple structure and resistance to ablation.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A multi-point charging device for a flash reduction ironmaking / steelmaking furnace includes a silo, a pressure equalization tank, a spray tank, several conveying pipes, and nozzles. The silo is connected to the pressure equalization tank via a valve, and the pressure equalization tank is connected to the spray tank via a valve. The spray tank is a hollow cavity. The spray tank is connected to the initial ends of several conveying pipes, and the ends of the conveying pipes are connected to nozzles. The nozzles are installed on the furnace wall at the top of the smelting furnace, and a carrier gas pipe is connected to the spray tank.

[0007] The nozzle includes a nozzle body and a charge channel that runs through the nozzle body. The two ends of the charge channel are the nozzle inlet and the nozzle outlet, respectively, and the nozzle outlet faces the interior space of the furnace.

[0008] The silo, serving as a storage unit for furnace charge, is connected to a pressure equalization tank via a valve for supplying charge to the pressure equalization tank. The pressure equalization tank is connected to a jetting tank via another valve; its main function is to balance pressure and ensure that high-pressure gas does not backflow into the silo when charge is added to the jetting tank. The jetting tank is a hollow, pressure-bearing cavity that serves as a temporary storage and fluidization container for the furnace charge before it is transported by carrier gas. It is connected to a carrier gas pipe for introducing high-pressure carrier gas. The initial ends of the multiple conveying pipes are all connected to the jetting tank, used to divert and transport the furnace charge within the jetting tank to various distribution points. The ends of the conveying pipes are connected to nozzles embedded in the furnace wall. The nozzle inlets are located on the outer side of the furnace wall and connected to the conveying pipes, while the nozzle outlets are located on the inner side of the furnace wall, pointing towards the reaction space inside the furnace. During operation, high-pressure carrier gas enters the jetting tank, fluidizing the furnace charge within and carrying it into each conveying pipe. Finally, the charge is injected at high speed into the furnace from each nozzle, achieving multi-point, dispersed initial distribution of the charge.

[0009] Preferably, the charging device includes a charging air system comprising at least one charging air duct connected to the charge channel of the nozzle. The charging air duct inlet is located outside the furnace wall or outside the nozzle body and is connected to the charging air supply system; the charging air duct outlet is located on the side wall of the charge channel, near the nozzle outlet. Importantly, the orientation of this outlet is carefully designed so that the ejected high-speed charging air can directly impact the charge jet within the charging air duct. This high-speed airflow can further disperse any agglomerated charge and impart additional kinetic energy and directionality to the charge particles, resulting in a more dispersed and uniform distribution within the furnace.

[0010] Furthermore, to adapt to the harsh working conditions of high temperature and charge scouring inside the furnace, the nozzle is preferably made of high-temperature resistant and wear-resistant industrial ceramic material. In addition, the nozzle outlet and the material distribution air channel outlet can be designed into different shapes according to process requirements, such as circular, flat slit, or porous shapes, to control the jet shape and diffusion angle.

[0011] Furthermore, to achieve precise control of the flow field within the furnace, the distribution of the multiple nozzles on the furnace wall and the installation angle of the nozzles are arranged and set according to preset material distribution requirements. Even further, the installation angle of each nozzle or the direction of its ejected gas-material jet can be configured to a specific direction, allowing multiple jets to intersect and overlap within the furnace space, thereby forming an ideal and uniform material distribution and flow field across the entire furnace cross-section.

[0012] Furthermore, to enable immediate cessation of feeding, this invention incorporates a self-locking section or a shut-off valve on the feeding pipe. The self-locking section can be a horizontal pipe, an inclined pipe with an angle greater than the material's natural angle of repose to the horizontal plane, or an S-shaped bend. The principle is that when the carrier gas supply stops, the remaining furnace material within the self-locking section, under the combined action of gravity and potential furnace pressure, will accumulate and become jammed within the pipe, forming a natural "material seal," thus effectively stopping the feeding. The shut-off valve provides an option for active control.

[0013] Furthermore, to improve equipment lifespan and cope with the severe wear of the pipeline caused by high-speed gas-solid two-phase flow, the inner wall of the conveying pipe can be lined with a ceramic wear-resistant lining, such as high-alumina ceramic or silicon carbide ceramic.

[0014] Furthermore, to improve the flowability of materials within the injection tank and conveying pipe, and to prevent bridging and blockage at the bottom of the tank, the pipe inlet, or within the pipe, one or more air inlets for introducing loosening gas can be provided at the bottom of the injection tank and / or on the conveying pipe. Introducing a small amount of loosening gas can keep the material in a loose state, ensuring smooth discharge.

[0015] Furthermore, the carrier gas may contain one or more combinations of reducing gases (such as hydrogen and carbon monoxide), carbon dioxide, and inert gases (such as nitrogen and argon). For example, in the hydrogen metallurgical flash ironmaking process, pressurized hydrogen is preferably used as the carrier gas, as it serves as both a transport medium and a reducing agent and energy carrier.

[0016] Furthermore, to achieve precise material balance control and automated operation, weighing devices (such as electronic scales or pressure sensors) and / or level detection devices (such as radar level gauges or hammer level gauges) can be installed on the blowing tank and / or equalizing tank. By monitoring the weight or level of the material in the tank in real time, the feeding rate and total feeding amount can be precisely controlled.

[0017] This invention also provides a method for multi-point charging in a flash reduction ironmaking / steelmaking furnace using the aforementioned multi-point charging device. The core of this method is as follows: First, the furnace charge is loaded into the silo, and through the balancing effect of the equalizing tank, the furnace charge is safely transferred to the injection tank; then, high-pressure carrier gas is introduced into the injection tank to fluidize the furnace charge; under the action of pressure difference, the fluidized furnace charge is evenly distributed into multiple conveying pipes; finally, the furnace charge is injected into the smelting furnace in the form of a high-speed jet through the nozzles at the end of each conveying pipe, achieving the effect of evenly distributing the furnace charge into the furnace from multiple spatial points.

[0018] In a preferred embodiment, the method further includes simultaneously ejecting a high-speed airflow from the material distribution channel when the charge is ejected from the nozzle. This airflow impacts and shears the main material jet, further dispersing it into a finer particle cloud, thereby enhancing the initial mixing effect between the charge and the reacting gases in the furnace.

[0019] Furthermore, the carrier gas in this method can be selected according to different smelting processes. In the hydrogen reduction flash ironmaking process, pressurized hydrogen is preferred as the carrier gas to simultaneously perform multiple functions of transporting, reducing, and providing energy.

[0020] Finally, the method also includes a step for precisely controlling the start and stop of feeding. When it is necessary to stop feeding, the shut-off valve on the feed pipe can be closed manually, or the carrier gas delivery can be stopped and the self-locking structure (such as the self-locking section) on the feed pipe can be used to naturally lock the furnace charge in the pipeline, thereby reliably preventing the backflow of high-temperature gas in the furnace and ensuring system safety and the flexibility of production operation.

[0021] When the fabric tube becomes blocked, unblocking air is introduced through the unblocking air inlet to clear the blockage. The unblocking air is one or more of a reducing gas, an inert gas, or carbon dioxide gas; preferably, the unblocking air is hydrogen; more preferably, the unblocking air is pressurized gas.

[0022] The present invention also provides a co-current flash furnace, including at least one set of the above-mentioned material distribution device disposed on the furnace top; The co-current flash furnace includes a main furnace reaction zone, an auxiliary furnace reaction zone, and a molten pool zone. The molten pool zone is located at the lower part of the furnace body. The main furnace reaction zone and the auxiliary furnace reaction zone are located above the molten pool zone, and the lower end of the auxiliary furnace reaction zone is directly connected to the lower end of the main furnace reaction zone. The main furnace reaction zone is divided into a solid reduction zone, a soft melting reduction zone, and a liquid zone from top to bottom; The auxiliary furnace reaction zone is provided with a gas-solid two-phase outlet at the top, and at least one auxiliary furnace feed nozzle is provided in the lower part of the auxiliary furnace reaction zone. The molten pool zone includes a slag layer and a molten iron layer; the sidewall of the molten pool zone is provided with a slag outlet and an iron outlet, and the molten pool zone is used to accommodate the slag and iron coming from the main furnace reaction zone and to perform slag and iron separation.

[0023] In this invention, the lower end of the auxiliary furnace reaction zone is directly connected to the lower end of the main furnace reaction zone. At least one auxiliary furnace feed nozzle is provided in the lower part of the auxiliary furnace reaction zone to inject ore powder into the zone. A gas-solid two-phase outlet is provided at the top of the auxiliary furnace reaction zone to discharge the pre-reduced flue gas. The auxiliary furnace reaction zone utilizes the high-temperature furnace gas discharged from the main furnace reaction zone to pre-reduce the ore. The pre-reduced ore is then discharged from the auxiliary furnace reaction zone with the gas flow.

[0024] By placing the auxiliary furnace feed nozzle in the lower part of the auxiliary furnace reaction zone, the high-temperature furnace gas rising from the main furnace reaction zone pre-reduces the ore, extending the effective residence time of the ore powder in the reduction zone. Compared with the existing technology where the airflow direction is the same as the falling direction of the ore powder, in this scheme, the ore powder enters from the lower part of the auxiliary furnace reaction zone, forming a reasonable flow match with the rising airflow in the main furnace reaction zone. This effectively extends the residence time of ore powder of various particle sizes in the pre-reduction zone, avoiding the problem of insufficient reduction caused by the accelerated settling of coarse particles and the rapid escape of fine particles with the airflow, and enhancing the gas-solid contact efficiency.

[0025] The auxiliary furnace reaction zone (pre-reduction zone) and the main furnace reaction zone (final reduction zone) are spatially connected, which also realizes the cascade utilization of thermal energy and improves the heat utilization efficiency of the flash process.

[0026] Meanwhile, the lower end of the auxiliary furnace reaction zone is directly connected to the lower end of the main furnace reaction zone, forming an integrated and compact layout that significantly reduces the equipment footprint and lowers equipment investment costs. This integrated structure is suitable for new projects and is also convenient for low-cost retrofitting of existing blast furnaces—for existing blast furnace workshops, the original furnace structure can be directly utilized, and flash ironmaking can be achieved by adding auxiliary furnaces or internal partitions, without the need for large-scale site expansion.

[0027] The present invention also provides a counter-current flash furnace, including at least one set of the above-mentioned material feeding device disposed on the furnace top; the counter-current flash furnace includes a furnace body; The furnace body consists of, from top to bottom, an air-classified material distribution zone, a solid reduction zone, a softening reduction zone, a molten liquid zone, and a molten pool zone; The lower part of the molten pool area is a layer of molten iron, and the upper part is a layer of slag. The furnace wall corresponding to the molten iron layer is provided with an iron tapping port, and the furnace wall corresponding to the slag layer is provided with a slag tapping port. The air-separated fabric area is equipped with an exhaust gas outlet; Fine material injection ports are provided on the furnace sidewalls corresponding to the upper part of the molten liquid zone and / or the lower part of the softening reduction zone. The carrier gas injected into the fine material injection ports is one or a combination of reducing gas, carbon dioxide, and system exhaust gas. A reducing gas inlet is provided near the molten liquid zone and / or the fine material injection inlet, which is used to provide the reducing gas and heat required for the reaction.

[0028] As the furnace charge passes through the solid reduction zone, the softening reduction zone, and the liquid zone in sequence, it transforms from a solid state into a softening state and then into a liquid state, respectively.

[0029] Preferably, in this invention, the part of the solid reduction zone near the point where it enters the softening reduction zone is provided with a sudden change section in the inner diameter of the furnace shell; the rate of change of the furnace diameter suddenly increases, and then may gradually decrease.

[0030] Preferably, the maximum flow area at the abrupt change section of the furnace shell diameter is 10% to 50% larger than the cross-section of the furnace body above it. The expanded flow area section extends to the molten liquid zone. The furnace charge in the softening and reduction zone is in a softened state and has high viscosity. By setting the furnace body diameter expansion section, the rising wind speed of the fine particles injected into the furnace area is reduced, and the molten material is prevented from sticking to the furnace wall.

[0031] This counter-current flash furnace improves the heat exchange and reaction efficiency between the reducing gas and the furnace charge through counter-current smelting, thereby reducing smelting costs. Furthermore, by employing a fine material injection device in the softening zone or molten liquid zone of the furnace body, smaller particles that cannot be fed into the furnace in counter-current mode are injected into this area for reaction and fall into the molten pool. This solves the problem of low smelting efficiency caused by the escape of smaller particles during counter-current smelting.

[0032] The present invention also provides a reverse-current coupled flash smelting furnace, including at least one set of the above-mentioned material distribution device arranged on the furnace top; the furnace body of the reverse-current coupled flash smelting furnace includes a molten pool zone arranged at the bottom of the cavity and a co-current reaction zone and a counter-current reaction zone located above the molten pool zone; The co-current reaction zone and the counter-current reaction zone are divided into a solid reduction zone, a soft melting reduction zone and a liquid zone from top to bottom according to the state of the furnace charge; The lower part of the molten pool zone is a layer of molten iron, and the upper part of the molten pool zone is a layer of slag. The sidewall of the molten pool zone is provided with an iron outlet in the height range of the molten iron layer and a slag outlet in the height range of the slag layer. The co-current reaction zone and the counter-current reaction zone are both independent vertical cavities, and the lower parts of the co-current reaction zone and the lower parts of the counter-current reaction zone are interconnected. A material distribution device is provided at the top of the furnace body where the co-current reaction zone is located and / or at the top of the furnace body where the counter-current reaction zone is located; A reducing agent supply unit is provided on the upper part of the furnace body where the co-current reaction zone is located. The reducing agent supply unit is used to provide the reducing gas and heat required for the reaction. The countercurrent reaction zone is located at the top of the furnace body, where an exhaust gas outlet is provided. As the furnace charge passes through the solid reduction zone, the softening reduction zone, and the liquid zone in sequence, it transforms from a solid state to a softening state and then to a liquid state, respectively.

[0033] This invention relates to a coupled co-current and counter-current flash smelting furnace, comprising a co-current reaction zone, a counter-current reaction zone, and a molten pool zone. Larger particle sizes of the charge enter the reaction zone from the counter-current zone, while smaller particle sizes enter from the co-current zone. Reducing gas is introduced from the top of the co-current reaction zone, reacting with the fine particles in a co-current flow. The gas then enters the counter-current reaction zone to react with the coarse particles in a counter-current heat exchange reaction. Finally, the exhaust gas exits from the top of the counter-current reaction zone. The molten material separates into molten iron and slag in the bottom molten pool zone and is discharged separately. This invention, through the coupling of co-current and counter-current processes, combines the advantages of both smelting methods while avoiding their respective disadvantages, effectively improving metal yield and overall energy efficiency, while reducing raw material grinding costs and exhaust gas heat loss.

[0034] Beneficial effects of the present invention Compared with the prior art, the present invention has the following significant advantages: Significantly improved material uniformity: Through the rational distribution of multiple nozzles on the furnace wall, combined with an independent material distribution air system, highly dispersed and uniformly distributed charge across the furnace cross-section can be achieved, avoiding localized accumulation and creating optimal initial conditions for efficient and uniform flash reaction. High system safety and reliability: By installing self-locking sections or shut-off valves on the feed pipes, the technical challenge of backflow of high-pressure, high-temperature gas inside the furnace is effectively solved, ensuring equipment and production safety.

[0035] Long service life: The conveying pipe is lined with ceramic wear-resistant material and the nozzle is made of industrial ceramic material, which significantly improves the erosion and wear resistance of key components of the equipment, extends the overall service life of the equipment, and reduces maintenance costs.

[0036] Precise control and easy automation: By setting up weighing devices and material level detection devices, the feeding process can be monitored and accurately measured in real time, providing a foundation for achieving fully automatic and intelligent smelting control.

[0037] Effectively prevents blockages: By setting air inlets at the bottom of the spray tank and on the conveying pipe, the flowability of materials is improved, effectively preventing material bridging and pipe blockage, and ensuring smooth and stable conveying process. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of the flash ironmaking fabrication device described in Example 1.

[0039] Figure 2 This is a schematic diagram of the nozzle structure of the flash ironmaking fabrication device described in Example 2.

[0040] Figure 3 This is a schematic diagram of the structure of the flash ironmaking fabrication device described in Example 3.

[0041] Figure 4This is a top view schematic diagram of the flash ironmaking fabrication device described in Example 3.

[0042] Figure 5 This is a schematic diagram of the co-current flash furnace described in Example 4.

[0043] Figure 6 This is a schematic diagram of the countercurrent flash furnace described in Example 5.

[0044] Figure 7 This is a schematic diagram of the forward and reverse coupled flash furnace described in Example 6.

[0045] Figure label: 1-Binding silo; 2-Valve; 3-Equalizing tank; 4-Pulse jet tank; 5-Raw material inlet; 6-Carrier gas inlet; 7-Conveying pipe; 8-Nozzle; 801-Nozzle inlet; 802-Nozzle outlet; 803-Charge material channel; 9-Burning air system; 901-Burning air channel inlet; 902-Burning air channel; 903-Burning air channel outlet; 10-Furnace wall; 11-Air venting; 12-Self-locking structure; 13-Weighing device; 14-Slag outlet; 15-Iron outlet; 16-Furnace body; 17-Reducing gas inlet; 18-Tail gas outlet; 100-Burning device; 1000-First furnace body; 1001-Second furnace body; 1002-Main furnace reaction zone; 1003-Auxiliary furnace reaction zone; 1004-Carbonizer spray gun; 1005-Gas-solid two-phase outlet; 1006-Auxiliary furnace feed spray gun; 1007-Gas-solid separation efficiency improvement device; 1008-Flow passage.

[0046] 101-Air-selected fabric zone; 102-Solid reduction zone; 103-Softening reduction zone; 104-Melted liquid zone; 105-Melted pool zone; 2000-Fine material injection inlet.

[0047] 3000 - Vertical partition wall; 3001 - Co-current reaction zone; 3002 - Countercurrent reaction zone; 3003 - Reducing agent replenishment unit. Detailed Implementation

[0048] Example 1 like Figure 1As shown, a flash reduction iron / steelmaking furnace charging device is provided. This device includes a silo 1 for storing furnace charge, with a raw material inlet 5 at the top connected to an upstream conveying system. The bottom outlet of the silo 1 is sealed to the top inlet of a pressure equalization tank 3 via a valve 2. The bottom outlet of the pressure equalization tank 3 is connected to the top inlet of a purging tank 4 via another valve 2. The purging tank 4 is a high-pressure, hollow, sealed cavity and is the core unit for fluidizing and conveying the furnace charge. A carrier gas inlet 6 is provided on the upper sidewall or top of the purging tank 4 for introducing high-pressure carrier gas, preferably high-pressure hydrogen in this embodiment. Multiple feed pipes 7 are uniformly connected to the initial ends of the lower part of the purging tank 4. The end of each feed pipe 7 is sealed to a nozzle 8 located within the furnace wall 10 at the top of the smelting furnace. The nozzle 8 includes a nozzle body and a charge channel penetrating the nozzle body. The two ends of the charge channel are the nozzle inlet and the nozzle outlet, respectively, with the nozzle outlet facing the interior space of the furnace.

[0049] During operation, the furnace charge enters the atmospheric pressure silo 1 through the raw material inlet 5. Before charging, valve 2 between silo 1 and pressure equalization tank 3 is first opened, allowing the furnace charge to fall into pressure equalization tank 3 by gravity. This valve is then closed, and valve 2 between pressure equalization tank 3 and injection tank 4 is opened, allowing the furnace charge to fall smoothly and quickly into injection tank 4 under the influence of pressure difference and gravity. This pressure equalization process effectively prevents gas in the high-pressure injection tank 4 from backflowing into the atmospheric pressure silo 1 during charging, ensuring system safety and stability.

[0050] After the charging is completed, the valve between the two tanks is closed. Then, high-pressure hydrogen is introduced into the injection tank 4 through the carrier gas inlet 6. Simultaneously, if the injection tank 4 is equipped with a fluidizing device at its bottom (not shown in the figure; the fluidizing device can be one or more air inlets, or a wind cap similar to that used in a fluidized bed can be added to the air inlet to further enhance the fluidization effect. It is generally located at the bottom of the injection tank, near the interface between the injection tank and the conveying pipe.), a small amount of fluidizing gas is introduced to fluidize the furnace charge inside the tank, giving it good fluidity similar to a fluid. Driven by the high pressure inside the tank, the carrier gas carries the fluidized furnace charge and is evenly pressed into each of the connected conveying pipes 7. The furnace charge is conveyed through the conveying pipes 7 to each nozzle 8 and injected into the furnace. Multiple nozzles 8 are evenly distributed on the circumference of the furnace top. The furnace charge ejected from the nozzles 8 falls evenly and dispersedly within the furnace space, rapidly contacting, exchanging heat with, and undergoing a reduction reaction in a suspended state with the hot reducing gas (such as hydrogen).

[0051] Example 2 Based on Example 1, this embodiment adds a fabric air system 9 to optimize the fabric effect and improves the nozzle structure.

[0052] like Figure 2As shown, the core of the charging air system 9 is at least one charging air channel 902 connected to the charge channel 803 of the nozzle 8. The charging air channel inlet 901 is located outside the nozzle body and is connected to an independent, adjustable pressure and flow charging air supply system via a pipe. The charging air channel 902 is integrated with the nozzle 8 and passes through the inside of the nozzle. The charging air channel outlet 903 is located on the side wall of the charge channel, close to the nozzle outlet 802. This design allows the charging air ejected from the charging air channel outlet 903 to be directed towards the main charge jet, enabling the high-speed charging air to impact and disperse the charge. Simultaneously, the charge channel 803 opposite the charging air channel outlet 903 is designed in an arc shape, further enhancing the dispersion effect of the charge after impact by making the charge channel at the nozzle outlet end in the direction of the charging air impact arc.

[0053] Example 3 like Figure 3 , Figure 4 As shown, this embodiment is a multi-point charging device for a flash blast furnace. The silo 1 is used to store furnace charge, and a raw material inlet 5 is provided at the top of the silo 1. The lower part of the silo 1 is connected to a pressure equalization tank 3 via a valve 2. The lower part of the pressure equalization tank 3 is connected to a injection tank 4 via a valve 2. The pressure equalization tank 3 delivers the furnace charge from the atmospheric pressure silo 1 into the high-pressure injection tank 4. A weighing device 13 is provided on the pressure equalization tank 3 to accurately control the total feed rate. A carrier gas inlet 6 is provided on the injection tank 4 to provide high-pressure carrier gas to spray the material out of the injection tank 4. The lower part of the injection tank 4 is connected to the initial ends of several conveying pipes 7, and the ends of the conveying pipes 7 are connected to nozzles 8. The discharge pipes 7 are used to deliver the fluidized furnace charge in the injection tank to the nozzles 8.

[0054] A ventilation inlet 11 is provided on the conveying pipe 7 to allow ventilation and prevent blockage inside the pipe, which would affect the material distribution rate and effect. A self-locking structure 12 is also provided on the conveying pipe 7. This self-locking structure is L-shaped or L-like, and the self-locking section is a horizontal pipe. When the air supply to the injection tank 4 stops, the furnace charge loses its power source, and the feeding automatically stops at the self-locking structure 12 due to the material's angle. The self-locking structure 2 enables the function of stopping the feeding at any time during the smelting process.

[0055] Several nozzles 8 are evenly distributed on the top wall of the smelting furnace, such as Figure 4 As shown, this achieves uniform distribution of the furnace charge within the furnace body. The nozzle 8 is embedded in the top wall of the smelting furnace. The nozzle inlet 801 is located on the outer side of the top wall of the smelting furnace, and the nozzle outlet 802 is located on the inner side of the top wall of the smelting furnace. A charging air channel 902 is also provided on the nozzle 8, and the outlet 903 of the charging air channel is located on the path of the furnace charge movement at the nozzle outlet 802. Figure 2As shown. By setting the feeding air, the high-speed feeding air can directly impact the furnace charge jet ejected from the nozzle, giving the furnace charge particles additional kinetic energy and directionality, making them more dispersed and uniformly distributed in the furnace.

[0056] When the multi-point feeding device is in operation, the furnace charge enters the silo 1 through the raw material inlet 5 for storage. By controlling the opening and closing of the valve 2, a certain amount of furnace charge is sent from the silo 1 into the equalizing tank 3, and weighed by the weighing device 13 to obtain the weight information of the furnace charge entering the furnace. The furnace charge enters the injection tank 4 through the opening and closing of the valve located at the bottom of the equalizing tank 3. High-pressure hydrogen gas is introduced into the injection tank through the carrier gas inlet 6, and the furnace charge is sent through the conveying pipe 7 to the nozzle 8 and injected into the furnace.

[0057] Example 4 A type of co-current flash furnace, such as Figure 5 As shown, the furnace top is equipped with the material feeding device 100 described in Embodiment 1, and the furnace body 16 includes a first furnace body 1000 and a second furnace body 1001. The upper part of the first furnace body 1000 is provided with a reducing gas inlet 17.

[0058] The lower end of the second furnace body 1001 is connected to the side wall of the first furnace body 1000. Specifically, the lower end of the second furnace body 1001 is inclined downwards and connected to the side wall of the first furnace body 1000. The main furnace reaction zone 1002 and the molten pool zone 105 are arranged from top to bottom within the first furnace body 1000. A carbon raiser spray gun 1004 is inserted into the slag layer of the molten pool zone 105. The auxiliary furnace reaction zone 1003 is located within the second furnace body 1001. The top of the auxiliary furnace reaction zone 1003 is provided with a gas-solid two-phase outlet 1005, which can be connected to a dust collector to recover powder materials.

[0059] A gas-solid separation efficiency improvement device 1007 is installed on the lower side wall of the main furnace reaction zone 1002. The gas-solid separation efficiency improvement device 1007 includes an annular baffle wall installed on the inner wall of the furnace body and a flow passage 1008 located at the center of the annular baffle wall. At the flow passage 1008, the flow area of ​​the furnace cavity is reduced, and the area is 5% to 50% of the inner diameter area of ​​the main furnace reaction zone 1002.

[0060] The auxiliary furnace reaction zone is directly connected to the main furnace reaction zone. The connection point is located in the lower part of the main furnace reaction zone. At least one auxiliary furnace feed nozzle 1006 is provided in the lower part of the auxiliary furnace reaction zone, and a gas-solid two-phase outlet is provided at the top. The furnace gas in the main furnace reaction zone is used to pre-reduce the ore.

[0061] Example 5 A type of counter-current flash furnace, such as Figure 6As shown, the furnace top is equipped with the material distribution device 100 described in Example 1. The internal space of the furnace body 16 is divided from top to bottom into an air-classifying material distribution zone 101, a solid reduction zone 102, a softening reduction zone 103, a molten liquid zone 104, and a molten pool zone 105. The molten pool zone at the bottom is divided into a slag layer and a molten iron layer. A slag outlet 14 is provided in the slag layer height direction, and an iron outlet 15 is provided in the molten iron layer height direction.

[0062] A reducing gas inlet 17 is provided at the lower part of the molten liquid zone 104 and / or near the fine material injection inlet 2000. The reducing gas inlet 17 is used to provide the reducing gas and heat required for the reaction. The reducing gas inlet is located on the side wall of the furnace body 16.

[0063] The furnace charge enters the flash furnace through the charge inlet of the charging device 100 and moves downwards. The high-temperature reducing gas is hydrogen, which enters the furnace body through the reducing gas inlet and moves upwards. The high-temperature hydrogen moves in the opposite direction to the furnace charge, and a reaction and heat exchange occur during the movement.

[0064] Fine particles enter the furnace body through the fine material inlet 2000 and rapidly react with high-temperature hydrogen in the molten liquid zone 104 or the softening reduction zone 103. They are also agglomerated by collisions with the falling furnace charge, which is already in a softened or molten state, and fall together into the bottom molten pool zone 105. The exhaust gas from the reaction is discharged from the furnace body 16 through the exhaust gas outlet 18.

[0065] Example 6 A type of forward and reverse coupled flash smelting furnace, such as Figure 7 As shown, the smelting furnace body 16 is a vertical furnace body. A vertical partition wall 3000, connected to the side wall of the furnace body, is installed above the inner cavity of the vertical furnace body, dividing the upper smelting zone of the furnace body 16 into a co-current reaction zone 3001 and a counter-current reaction zone 3002. A material distribution device 100 is installed at the top of both the co-current reaction zone 3001 and the counter-current reaction zone 3002. The material distribution device 100 is connected to a furnace material sorting device, which is either an air classifier or a dry airflow screening device. A main silo is connected before the sorting device. The sorting device separates the furnace material into two parts: a larger particle size and a smaller particle size, which are then fed into the corresponding material distribution devices 100 in the counter-current reaction zone 3002 and the co-current reaction zone 3001, respectively.

[0066] A reducing agent supply unit is provided on the upper part of the furnace body where the co-current reaction zone 3001 is located. In this embodiment, the reducing agent supply unit includes a reducing gas inlet 17 and a reducing gas and supplementary heating gas inlet. A tail gas outlet 18 is provided on the upper part of the furnace body where the counter-current reaction zone 3002 is located.

[0067] The molten pool zone 105 is located at the bottom of the vertical furnace body. The upper part of the molten pool zone 105 is a slag layer, and the lower part is a molten iron layer. A slag outlet 14 is provided in the slag layer height range, and an iron outlet 15 is provided in the molten iron layer height range.

[0068] The vertical furnace body has the same shape from top to bottom; for example, the vertical furnace body is a cylindrical structure or a cubic structure.

[0069] Smaller particle sizes of the furnace charge are fed into the co-current reaction zone 3001, where they move downwards. Larger particle sizes of the furnace charge are fed into the counter-current reaction zone 3002, where they move downwards.

[0070] In this embodiment, hydrogen is selected as the reducing gas. After being heated, the high-temperature hydrogen enters the vertical furnace through the reducing gas inlet. In the co-current reaction zone 3001, the high-temperature hydrogen and the smaller particle size furnace charge move downwards in the same direction, reacting and exchanging heat simultaneously. High-temperature hydrogen is introduced through the reducing gas and supplementary heating gas inlets to further melt the smaller particle size furnace charge that has already undergone reaction at the lower part of the co-current reaction zone 3001, causing it to fall into the molten pool zone 105 below. At the same time, sufficient heat and reducing gas are supplied to ensure that the reducing gas reaches the reaction in the counter-current reaction zone 3002.

[0071] High-temperature hydrogen gas enters the lower part of the co-current reaction zone 3001 and then the lower part of the counter-current reaction zone 3002. Within the counter-current reaction zone 3002, it moves upwards, moving counter-currently to the larger-diameter furnace charge moving downwards, simultaneously undergoing reaction and heat exchange. When the larger-diameter furnace charge reaches the lower part of the counter-current reaction zone 3002, the reaction is complete, and it falls into the molten pool zone 105 in a molten state. The reaction gas tail gas is discharged from the furnace body through the tail gas outlet 18.

[0072] In this embodiment, a reducing agent replenishment unit 3003 is provided at the lower part of the co-current reaction zone 3001, including a reducing gas inlet or a composite spray gun containing carbon-containing fuel and oxygen-containing combustion-supporting gas. The reducing gas inlet is used to introduce high-temperature reducing gas. The carbon-containing fuel used in the composite spray gun is pulverized coal, coal gas, or natural gas, and the oxygen-containing combustion-supporting gas is pure oxygen or oxygen-enriched gas, used to prepare high-temperature reducing gas through reaction in the furnace.

Claims

1. A multi-point charging device for a flash reduction ironmaking / steelmaking furnace, characterized in that, It includes a silo, a pressure equalization tank, a spray tank, several conveying pipes, and nozzles; the silo is connected to the pressure equalization tank via a valve, the pressure equalization tank is connected to the spray tank via a valve, the spray tank is a hollow cavity, the spray tank is connected to the initial end of several conveying pipes, and the end of the conveying pipes is connected to the nozzles; a carrier gas pipe is connected to the spray tank.

2. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, The nozzle includes a nozzle body and a charge channel that runs through the nozzle body. The two ends of the charge channel are the nozzle inlet and the nozzle outlet, respectively.

3. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 2, characterized in that, The material distribution device also includes a material distribution air system, which includes at least one material distribution air channel connected to the charge channel of the nozzle. The inlet of the material distribution air channel is located outside the furnace wall or outside the nozzle body and is connected to the material distribution air supply system. Its outlet is located on the side wall of the charge channel, close to the nozzle outlet, and the orientation of the outlet is such that the material distribution air impacts the charge ejected from the nozzle.

4. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, The nozzle is made of industrial ceramic material, and the nozzle outlet and the fabric air duct outlet can be of any shape.

5. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, The distribution of the nozzles on the furnace wall and the installation angle of the nozzles are determined according to the material feeding requirements.

6. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, The conveying pipe is equipped with a self-locking section or a shut-off valve. The self-locking section is a horizontal pipe, or a pipe that forms an angle with the ground greater than the natural stacking angle of the material, or an S-shaped pipe.

7. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, The inner wall of the conveying pipe is lined with a ceramic wear-resistant liner.

8. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, One or more air inlets are provided at the bottom of the spray tank and / or on the conveying pipe.

9. The multi-point charging device for flash reduction ironmaking / steelmaking furnaces as described in claim 1, characterized in that, Weighing devices and / or material level detection devices are installed on the spray tank and / or equalizing tank.

10. A multi-point charging method for flash reduction ironmaking / steelmaking furnaces, characterized in that, Using the multi-point material distribution device according to any one of claims 1-9, the furnace charge in the injection tank is transported to the smelting furnace through multiple conveying pipes and corresponding nozzles by carrier gas, so as to achieve uniform distribution of the furnace charge into the furnace from multiple nozzles.

11. The multi-point charging method for flash reduction ironmaking / steelmaking furnaces as described in claim 10, characterized in that, When the furnace charge is ejected through the nozzle, a high-speed airflow is ejected through the material distribution air channel located near the nozzle, which impacts and further disperses the furnace charge.

12. The multi-point charging method for flash reduction ironmaking / steelmaking furnaces as described in claim 10, characterized in that, The carrier gas is one or more of a reducing gas, an inert gas, or carbon dioxide gas; preferably, the carrier gas is hydrogen; more preferably, the carrier gas is a pressurized carrier gas.

13. The multi-point charging method for flash reduction ironmaking / steelmaking furnaces as described in claim 10, characterized in that, The feeding can be stopped immediately by a self-locking structure or shut-off valve installed on the feeding pipe; when the feeding pipe is blocked, unclogged gas is introduced through the unclogged gas inlet; the unclogged gas is one or more of a reducing gas, an inert gas or carbon dioxide gas, preferably hydrogen; more preferably, the unclogged gas is pressurized gas.

14. A co-current flash furnace, characterized in that, Includes at least one set of material distribution device as described in any one of claims 1 to 9, disposed on the top of the furnace; The co-current flash furnace includes a main furnace reaction zone, an auxiliary furnace reaction zone, and a molten pool zone. The molten pool zone is located at the lower part of the furnace body. The main furnace reaction zone and the auxiliary furnace reaction zone are located above the molten pool zone, and the lower end of the auxiliary furnace reaction zone is directly connected to the lower end of the main furnace reaction zone. The main furnace reaction zone is divided into a solid reduction zone, a soft melting reduction zone, and a liquid zone from top to bottom; The auxiliary furnace reaction zone is provided with a gas-solid two-phase outlet at the top, and at least one auxiliary furnace feed nozzle is provided in the lower part of the auxiliary furnace reaction zone. The molten pool zone includes a slag layer and a molten iron layer; the sidewall of the molten pool zone is provided with a slag outlet and an iron outlet, and the molten pool zone is used to accommodate the slag and iron coming from the main furnace reaction zone and to perform slag and iron separation.

15. A countercurrent flash furnace, characterized in that, Includes at least one set of material distribution device as described in any one of claims 1 to 9, disposed on the top of the furnace; The countercurrent flash furnace is divided into four zones from top to bottom: an air-classified material distribution zone, a solid reduction zone, a softening reduction zone, a molten liquid zone, and a molten pool zone. The lower part of the molten pool area is a layer of molten iron, and the upper part is a layer of slag. The furnace wall corresponding to the molten iron layer is provided with an iron tapping port, and the furnace wall corresponding to the slag layer is provided with a slag tapping port. The air-separated fabric area is equipped with an exhaust gas outlet; Fine material injection inlets are provided on the furnace sidewalls corresponding to the upper part of the molten liquid zone and / or the lower part of the softening and reduction zone. A reducing gas inlet is provided near the molten liquid zone and / or the fine material injection inlet.

16. A forward and reverse coupled flash smelting furnace, characterized in that, Includes at least one set of material distribution device as described in any one of claims 1 to 9, disposed on the top of the furnace; The furnace body of the reverse-coupling flash smelting furnace includes a molten pool zone located at the bottom of the cavity and a co-current reaction zone and a counter-current reaction zone located above the molten pool zone; The co-current reaction zone and the counter-current reaction zone are divided into a solid reduction zone, a soft melting reduction zone and a liquid zone from top to bottom according to the state of the furnace charge; The lower part of the molten pool zone is a layer of molten iron, and the upper part of the molten pool zone is a layer of slag. The sidewall of the molten pool zone is provided with an iron outlet in the height range of the molten iron layer and a slag outlet in the height range of the slag layer. The co-current reaction zone and the counter-current reaction zone are both independent vertical cavities, and the lower parts of the co-current reaction zone and the lower parts of the counter-current reaction zone are interconnected. A material distribution device is provided at the top of the furnace body where the co-current reaction zone is located and / or at the top of the furnace body where the counter-current reaction zone is located; A reducing agent supply unit is provided on the upper part of the furnace body where the co-current reaction zone is located, and a tail gas outlet is provided on the upper part of the furnace body where the counter-current reaction zone is located.

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