A counter-coupled flash smelting furnace and method

Abstract

The application discloses a reverse and direct coupling flash smelting furnace and method, and belongs to the technical field of metallurgy. The furnace body comprises a direct flow reaction zone, a reverse flow reaction zone and a molten pool zone. Larger particle size furnace charges enter the reaction from the reverse flow reaction zone, and smaller particle size furnace charges enter the reaction from the direct flow reaction zone. Reducing gas is introduced from the upper part of the direct flow reaction zone, and after the gas reacts with fine particles in the direct flow downward, the gas enters the reverse flow reaction zone to exchange heat with coarse particles in the reverse flow, and finally tail gas is discharged from the upper part of the reverse flow reaction zone. Molten materials are separated into molten iron and slag layers in the bottom molten pool and discharged respectively. The method couples the reverse flow and the direct flow, integrates the advantages of the two smelting modes, avoids the shortcomings of the two smelting modes, effectively improves the metal yield and the overall energy efficiency, and reduces the raw material grinding cost and the tail gas heat loss.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical technology, specifically relating to a reverse-coupling flash smelting furnace and method. Background Technology

[0002] Flash ironmaking is a cutting-edge technology in the metallurgical field. It involves mixing and contacting fine iron ore powder with reducing gas at high temperatures, completing the reduction reaction within seconds. Compared with traditional blast furnace processes, flash ironmaking has significant advantages such as high reaction efficiency, the ability to achieve low-carbon or even carbon-free smelting, strong raw material adaptability, and a short process flow.

[0003] In existing flash ironmaking processes, gas-solid contact reactions only have two modes: countercurrent and cocurrent. In cocurrent, the ore powder and reducing gas move downwards in the same direction. The advantage of this mode is that it eliminates the problem of finer particles escaping from the feed material at the inlet. However, its disadvantages include lower heat and mass transfer efficiency compared to countercurrent; high exhaust gas temperature leading to low thermal efficiency; and the need to accommodate finer particle sizes, increasing grinding costs. In contrast, countercurrent contact (ore powder downwards, reducing gas upwards) significantly improves mass and heat transfer efficiency and increases thermal efficiency. It also accommodates a wider range of material sizes, saving grinding costs. However, its disadvantage is that fine particles cannot be prevented from being carried away by the exhaust gas and entering the reaction zone, severely limiting metal yield.

[0004] Therefore, in order to solve the above-mentioned problems of the two contact methods of co-current and counter-current, and to give full play to their respective advantages, the present invention proposes a new technical solution. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a co-current and counter-current coupled flash smelting furnace and method. By setting up independent co-current and counter-current reaction zones, this invention allows mineral powders of different particle sizes to be reduced in the co-current and counter-current reaction zones respectively. This combines the advantages of high heat and mass transfer efficiency, good thermal energy utilization, and wide adaptability to particle size of counter-current reaction, with the advantages of co-current reaction in handling fine powders and preventing particle escape. This effectively improves metal yield and overall energy efficiency, while reducing raw material grinding costs and tail gas heat loss.

[0006] The technical problem to be solved by the present invention is achieved by the following technical solution: a countercurrent coupled flash smelting furnace, comprising a furnace body, wherein the furnace body comprises a molten pool zone disposed at the bottom of the cavity and a cocurrent reaction zone and a countercurrent 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. The top of the furnace body where the co-current reaction zone is located is provided with a first charge inlet, and the top of the furnace body where the counter-current reaction zone is located is provided with a second charge inlet; 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.

[0007] Preferably, the reducing agent supply unit of the present invention includes a reducing gas inlet and a gas heating unit, wherein the reducing gas inlet is disposed on the side wall of the smelting furnace body and the reducing gas inlet is connected to the gas heating unit; The gas heating unit is used to heat the reducing gas; the reducing gas is room temperature reducing gas or preheated reducing gas; Preferably, the gas heating unit is a combustion chamber or a plasma heating device; Preferably, the combustion chamber is a cavity protruding from the furnace body, with a combustion nozzle at one end along the axial direction of the combustion chamber and a reducing gas outlet at the other end, the reducing gas outlet being connected to a reducing gas inlet on the side wall of the furnace body; The combustion nozzle is equipped with a fuel inlet and an auxiliary combustion gas inlet; At least one reducing gas injection inlet is provided on the combustion end and / or side wall of the combustion chamber. The reducing gas injected through the reducing gas injection inlet flows closely against the circumferential side wall of the combustion chamber to form an air curtain. The fuel and combustion-supporting gas are burned in the chamber of the original gas heater to generate heat, which is used to heat the reducing gas. At the same time, the reducing gas forms an air curtain in the chamber of the original gas heater to cool down the combustion chamber and protect the inner wall of the combustion chamber. Preferably, the reducing gas injection inlet forms an angle with the axis of the combustion chamber to form a spiral gas curtain. After the reducing gas enters through the reducing gas injection inlet, it moves in a spiral shape close to the side wall of the combustion chamber, which increases the travel before entering the reducing gas inlet and helps to increase the temperature of the reducing gas. Alternatively, the reducing agent supply unit may include a reducing gas inlet and a supplementary heating gas inlet located on the side wall of the smelting furnace, or may include a reducing gas inlet and a supplementary heating gas production material supply device located on the side wall of the smelting furnace. The reducing gas inlet is used to supply ambient temperature reducing gas or preheated reducing gas, and the supplementary heating gas inlet or the supplementary heating gas production material supply device is used to provide heat. Alternatively, the reducing agent supply unit may include a composite spray gun containing carbon-containing fuel and oxygen-containing combustion-supporting gas installed on the side wall of the smelting furnace, which generates reducing hot flue gas through incomplete combustion inside the furnace. Preferably, the fuel is pulverized coal, coal gas, or natural gas, and the combustion-supporting gas is pure oxygen or oxygen-enriched gas.

[0008] Preferably, the present invention further includes a reducing agent replenishment unit and / or a heat replenishment unit; The reducing agent replenishment unit and the heating unit are located in the middle and / or lower part of the co-current reaction zone, or in the lower part of the counter-current reaction zone; The reducing agent replenishment unit is a reducing gas inlet or a composite spray gun containing carbon fuel and oxygen-containing combustion-supporting gas, used to replenish thermal reducing gas; The heating unit is a hot flue gas inlet or a feedstock supply device for heating gas production. Through this structure, reducing gas and / or heat can be supplemented, improving the efficiency of the reduction reaction. When the gas flow inside the furnace moves upwards, there may be insufficient heat or insufficient reducing gas. In such cases, it is necessary to supplement only heat or supplement only hot reducing gas. The hot flue gas inlet refers to hot carbon dioxide, which only supplements heat.

[0009] Preferably, the inlet end of the reducing gas inlet, or the inlet end of the plasma heating device or combustion chamber connected to the reducing gas inlet, is also connected to a reducing gas supply device. Preferably, the reducing gas supply device is one or a combination of a coal gasifier or coal-to-hydrogen device, an electrolytic hydrogen device, a coke oven gas-to-hydrogen device, a methanol-to-hydrogen device, and an ammonia-to-hydrogen device. The coal gasifier or coal-to-hydrogen device, the electrolytic hydrogen device, the coke oven gas-to-hydrogen device, the methanol-to-hydrogen device, and the ammonia-to-hydrogen device can employ existing technologies.

[0010] Preferably, the present invention provides a furnace body expansion section at a height close to the entrance of the softening and reduction zone in the furnace body where the co-current reaction zone and / or counter-current reaction zone are located; "close to the entrance of the softening and reduction zone" can be understood as "the boundary between the solid reduction zone and the softening and reduction zone"; Preferably, the maximum flow area of ​​the furnace body expansion section is 10% to 50% larger than that of the upper furnace body, and the expansion section extends into the liquid zone of the furnace charge. The furnace charge in the softening and reduction zone is in a softened state and has high viscosity. By setting the furnace body expansion section, the rising wind velocity of fine particles injected into the furnace area is reduced, and the molten material is prevented from sticking to the furnace wall.

[0011] Preferably, in this invention, the exhaust gas outlet is connected to the first dust collector, and the air outlet of the first dust collector is connected to the hot-side inlet of the heat exchange device. The hot-side outlet of the heat exchange device is connected in sequence to the carbon dioxide removal device and the dehydration device. The outlet of the dehydration device is connected to the inlet of the circulating fan. The outlet of the circulating fan is connected to the cold-side inlet of the heat exchange device. The cold-side outlet of the heat exchange device is connected to the inlet of the combustion chamber or the plasma heating device. The discharge ports of the first and second dust collectors are connected to the hopper of the material distribution device in the co-current reaction zone. Preferably, a sulfur dioxide removal device is provided between the hot-side outlet of the heat exchange device and the second dust collector; Preferably, a hydrogen conversion device is installed between the outlet of the second dust collector and the carbon dioxide removal device. The first dust collector can be a cyclone dust collector, a multi-tube dust collector, or a high-temperature ceramic dust collector, and the second dust collector can be a bag filter. The heat exchange device can recover and utilize the heat in the exhaust gas, while the external supply network and the hydrogen conversion device can recover and utilize the reducing gas in the exhaust gas. The hydrogen conversion device can prepare CO into hydrogen and send it back into the furnace to continue participating in the reaction, so as to make full use of the exhaust gas. Alternatively, after removing carbon dioxide, the carbon monoxide in the exhaust gas can be returned. The reduction potential of hydrogen to reduce iron is better than that of carbon monoxide.

[0012] Preferably, the present invention includes a gas-solid separation efficiency-enhancing device located at the lower part of the co-current reaction zone. This device comprises an annular baffle wall on the inner wall of the furnace body and a flow passage at the center of the annular baffle wall. The flow passage forms a throat structure, which increases the probability of collision and fusion of the softening charge particles. By increasing the size of the charge in the exhaust gas, the gas cannot carry the charge particles, promoting the separation of the reacting gas from the molten charge and facilitating the molten charge to fall into the molten pool, thus achieving the purpose of gas-solid separation.

[0013] Preferably, the furnace body of the smelting furnace of the present invention comprises a vertical furnace body; A vertical partition wall connected to the side wall of the furnace body is provided above the inner cavity of the vertical furnace body, dividing the space above the inner cavity of the furnace body into a co-current reaction zone and a counter-current reaction zone; The molten pool zone is located at the bottom of the vertical furnace body; Preferably, the vertical furnace body has a consistent shape from top to bottom, which can reduce the cost and difficulty of furnace construction.

[0014] Preferably, the furnace body of the present invention includes a first furnace body, a second furnace body, and a connecting pipe; The molten pool zone is located at the bottom of the first furnace body; The second furnace body is connected to the side wall of the first furnace body by a connecting pipe; by setting the co-current reaction zone and the counter-current reaction zone in the second furnace body and the first furnace body or the first furnace body and the second furnace body respectively, this structure occupies a smaller area compared with the furnace body structure with a horizontal molten pool. Preferably, the smelting furnace body includes one or more first furnace bodies and / or one or more second furnace bodies. By setting multiple first furnace bodies or multiple second furnace bodies, the corresponding furnace charge processing capacity can be increased.

[0015] Preferably, the furnace body of the present invention includes a third furnace body, a fourth furnace body, and a horizontal molten pool; The third and fourth furnace bodies are respectively located at both ends of the horizontal molten pool, and are connected to the horizontal molten pool. The countercurrent reaction zone and the cocurrent reaction zone are located within the third and fourth furnace bodies, respectively, or within the fourth and third furnace bodies, respectively.

[0016] Preferably, in this invention, the shape of the molten pool region is elongated in the horizontal direction to form an extended section, and an inlet for supplementary heating flue gas and / or thermal reducing gas is provided at the elongated end of the molten pool region; The tapping and slag outlets are located on the elongated end side of the molten pool zone. By setting the extension section and placing the tapping and slag outlets on the elongated end side of the molten pool zone, it is suitable for smelting iron ores with high viscosity, extending the flow distance of the molten material, and promoting the separation of molten iron from the slag layer. Furthermore, the inlet of supplemental heating flue gas and / or hot reducing gas is used to supplement heat to the molten pool, ensuring that the temperature of the molten iron is maintained above the preset temperature.

[0017] Preferably, the first and second furnace charge inlets are provided with multi-point material distribution devices, including multiple material distribution units disposed above the solid reduction zone. The material distribution units are respectively connected to the injection tank, the equalization tank, and the material distribution bin via material distribution pipes. The injection tank and / or the material distribution pipe are provided with a carrier gas inlet to inject the furnace charge into the flash blast furnace through the material distribution unit. Preferably, the furnace charge is a mixture of iron ore powder and flux; Preferably, the furnace charge further includes carbon powder or coal powder; Preferably, multiple charging units are evenly arranged within the cross-section of the furnace body. By setting multiple charging units above the solid reduction zone and introducing carrier gas into the carrier gas inlet, the furnace charge is evenly injected into the flash blast furnace through the charging units, thereby making full use of the internal space of the furnace body, achieving uniform charge distribution within the furnace, and ensuring sufficient reaction at all points on the same cross-section of the furnace body.

[0018] Preferably, the fabric distribution unit of the present invention is a steering wheel fabric distributor; the steering wheel fabric distributor includes a feed pipe, a main air supply pipe, and an air supply ring pipe; The feeding pipe is connected to the rear end of the material distribution pipe; the main air supply pipe enters the feeding pipe through an opening in the side wall of the feeding pipe and runs parallel to the feeding pipe, or the main air supply pipe is located outside the feeding pipe and runs downwards together with the feeding pipe; the air supply ring pipe is located at the end of the main air supply pipe, in the lower space of the feeding pipe, and multiple air jet holes are opened circumferentially on the pipe wall of the air supply ring pipe. By setting multiple material distribution points evenly distributed on the cross-section of the furnace, and combining them with a unique air supply pipe equipped with several air jet holes, a lateral component of the distributed airflow is generated. The lateral component of the airflow is used to change the falling situation of the ore powder, so that the iron ore powder has lateral displacement kinetic energy, and finally the ore powder is laterally dispersed during the falling process. This effectively overcomes the drawbacks of the traditional "central column" feeding method and realizes efficient mixing and heat exchange between the furnace charge and the reducing gas.

[0019] The design of the air supply ring pipe effectively avoids the limitation of existing technology where materials can only diffuse outward in a circumferential direction, and increases the uniform distribution of materials falling in the central area. At the same time, by changing the distribution air pressure and flow rate and designing the upper and lower jet holes, the furnace charge is forced to be further dispersed and its direction changed during the descent process, resulting in a more ideal material distribution effect. This can further improve the space utilization rate of the smelting furnace, reduce costs and increase efficiency.

[0020] Preferably, the material distribution unit of the present invention is a side-wind material distributor; the side-wind material distributor includes a nozzle disposed on the furnace top, the nozzle opening facing downward and inclined. A feeding channel is provided above the nozzle, and the feeding channel is connected to the material distribution pipe; The nozzle sidewall is provided with a material distribution air channel, and the outlet of the material distribution air channel is inclined towards the nozzle opening. By rationally distributing multiple nozzles on the furnace top and combining them with independent material distribution air channels, the furnace charge can be highly dispersed and uniformly distributed across the furnace cross-section, avoiding local accumulation and creating optimal initial conditions for efficient and uniform flash reaction.

[0021] Preferably, the fabric unit of the present invention is a U-shaped fabric distributor; the U-shaped fabric distributor includes a U-shaped tube connected to the fabric tube, the end of the U-shaped tube is bent upward to form a discharge port, and the discharge port is set vertically upward or inclined upward. Preferably, a ore baffle is installed on the charge injection path of the U-shaped tube outlet, and the ore baffle is fixedly installed inside the smelting furnace. By setting multiple charge distribution points evenly distributed on the cross-section of the furnace and combining them with a unique "upward injection" method, the charge is injected upward into the furnace in multiple streams under the action of the carrier gas. Natural dispersion is achieved by utilizing gravity and collision, effectively overcoming the drawbacks of the traditional "central column" type of charge feeding and realizing efficient mixing and heat exchange between the charge and the reducing gas.

[0022] By setting a baffle on the injection path of the discharge port, the upward-sprayed material flow actively impacts the baffle, forcing it to further disperse and change direction, resulting in a more ideal material distribution effect.

[0023] Preferably, the present invention further includes a furnace charge sorting device, wherein the furnace charge sorting device is an air classifier or a dry airflow screening device; The sorting device is connected to a main silo. The sorting device separates the furnace charge into two parts: a larger particle size and a smaller particle size. These parts are then sent to the corresponding silos in the countercurrent reaction zone and the cocurrent reaction zone, respectively, to improve smelting efficiency.

[0024] The present invention also discloses a reverse-coordinated flash smelting method, which uses the above-mentioned reverse-coordinated flash smelting furnace and includes the following steps: before feeding, the furnace charge is sorted into co-current reactant and counter-current reactant according to the particle size, the co-current reactant is fed into the co-current reaction zone from the first furnace charge inlet, and the counter-current reactant is fed into the counter-current reaction zone from the second furnace charge inlet; The reducing gas is introduced into the furnace from the upper part of the co-current reaction zone, or it is prepared in the upper part of the co-current reaction zone; The reducing gas and the co-current reactant move downwards in the co-current reaction zone and react and exchange heat. When they reach the lower part of the co-current reaction zone, the furnace charge falls into the molten pool zone in a molten state, while the reactant gas enters the lower part of the counter-current reaction zone from the lower part of the co-current reaction zone and moves upwards along the counter-current reaction zone, moving in the opposite direction to the counter-current reactant moving downwards in the counter-current reaction zone, and continues to react and exchange heat. After the countercurrent reactant reaches the lower part of the countercurrent reaction zone, it completes the reaction and falls into the molten pool zone in a molten state; the reduction tail gas is discharged through the tail gas outlet located at the upper part of the furnace body in the countercurrent reaction zone. Molten material falling into the molten pool zone melts and separates under the action of gravity, forming an iron layer and a slag layer, which are discharged from the furnace through the tapping port and slag port, respectively.

[0025] Preferably, the reducing gas is at least one or a combination of hydrogen, carbon monoxide, and methane. The reducing gas is heated using a plasma device to reach the temperature required for the reaction.

[0026] In a preferred embodiment of the present invention, pulverized coal and oxygen are injected into a co-current reaction zone to react, generating reducing gas CO and releasing heat.

[0027] Compared with the prior art, the beneficial effects of the present invention are: This invention includes a co-current reaction zone, a counter-current reaction zone, and a molten pool zone. Larger particle size charge enters the reaction zone from the counter-current reaction zone, while smaller particle size charge enters from the co-current reaction zone. Reducing gas is introduced from the top of the co-current reaction zone, reacts with the fine particles in a co-current flow, and then enters the counter-current reaction zone to react with the coarse particles in a counter-current heat exchange reaction. Finally, the exhaust gas is discharged 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 combines the advantages of both co-current and counter-current 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. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the co-current and counter-current coupled flash smelting furnace described in Example 1; Figure 2 This is a schematic diagram of the co-current and counter-current coupled flash smelting furnace described in Example 2; Figure 3 This is a schematic diagram of the co-current and counter-current coupled flash smelting furnace described in Example 3; Figure 4 This is a schematic diagram of a hydrogen production device. Figure 5 Schematic diagram of the steering wheel feeder Figure 1 ; Figure 6 This is a schematic diagram of the crosswind material distributor. Figure 7 This is a schematic diagram of the U-shaped fabric feeder. Figure 8 Schematic diagram of the reducing gas injection inlet in the combustion chamber Figure 1 ; Figure 9 Schematic diagram of the reducing gas injection inlet in the combustion chamber Figure 2 ; Figure 10 Schematic diagram of the reducing gas injection inlet in the combustion chamber Figure 3 ; Figure 11 Schematic diagram of the steering wheel fabric structure Figure 2 ; In the figure, 1 is the furnace body, 101 is the molten pool zone, 102 is the co-current reaction zone, 103 is the counter-current reaction zone, 1011 is the extension section, and 104 is the furnace body expansion section; 2. Iron tapping spout, 3. Slag tapping spout, 4. First furnace charge inlet, 5. Second furnace charge inlet, 6. Reducing agent supply unit, 7. Tail gas outlet; 8. Combustion chamber; 9. Reducing agent replenishment unit; 10. Reducing gas supply device; 11 First dust collector, 12 Heat exchanger, 13 Carbon dioxide removal device, 14 Hydrogen conversion device, 15 Annular baffle wall, 151 Flow passage; 100mm vertical furnace body, 200mm vertical partition wall; 300 First furnace body, 400 Second furnace body, 500 Connecting pipe; 600 third furnace body, 700 fourth furnace body, 800 horizontal molten pool; 16 Fabric unit, 17 Fabric tube, 18 Fabric bin; 1000 Steering wheel material feeder, 1001 Feed pipe, 1002 Main air supply pipe, 1003 Air supply ring pipe, 1004 Air jet hole; 2000 Side air distributor, 2001 Nozzle, 2002 Feed channel, 2003 Distribution air channel; 3000U-type material distributor, 3001U-type pipe, 3002 mineral material baffle, 3003 pipe dredging. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will now be clearly and completely described in conjunction with the accompanying drawings.

[0030] Example 1 like Figure 1 As shown in the figure, the co-current and counter-current coupled flash blast furnace described in this embodiment includes a vertical furnace body 100.

[0031] A vertical partition wall 200, connected to the side wall of the furnace body, is installed above the inner cavity of the vertical furnace body 100, dividing the upper smelting zone of the furnace body into a co-current reaction zone 102 and a counter-current reaction zone 103. A first charge inlet 4 is located at the top of the furnace body where the co-current reaction zone 102 is located, and a second charge inlet 5 is located at the top of the furnace body where the counter-current reaction zone 103 is located. Above the first charge inlet 4 and the second charge inlet 5, respectively, are silos. The two silos are connected to a charge 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 charge into two parts: a larger particle size and a smaller particle size, which are then fed into the corresponding silos of the counter-current reaction zone and the co-current reaction zone, respectively.

[0032] A reducing agent supply unit 6 is provided on the upper part of the furnace body where the co-current reaction zone 102 is located. In this embodiment, the reducing agent supply unit 6 includes a reducing gas inlet and a reducing gas and supplementary heating gas inlet. A tail gas outlet 7 is provided on the upper part of the furnace body where the counter-current reaction zone 103 is located.

[0033] The molten pool zone 101 is located at the bottom of the vertical furnace body 100. The upper part of the molten pool zone 101 is a slag layer, and the lower part is a molten iron layer. A slag outlet 3 is provided in the slag layer height range, and an iron outlet 2 is provided in the molten iron layer height range.

[0034] The vertical furnace body 100 has the same shape from top to bottom. For example, the vertical furnace body 100 is a cylindrical structure or a cubic structure.

[0035] Smaller-sized furnace charge is fed into the co-current reaction zone 102 through the first charge inlet 4 and moves downward within the co-current reaction zone 102. Larger-sized furnace charge is fed into the counter-current reaction zone 103 through the second charge inlet 5 and moves downward within the counter-current reaction zone 103.

[0036] In this embodiment, hydrogen is selected as the reducing gas. After being heated, the high-temperature hydrogen enters the vertical furnace 100 through the reducing gas inlet. In the co-current reaction zone 102, 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 102, causing it to fall into the molten pool zone 101 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 103.

[0037] High-temperature hydrogen gas enters the lower part of the countercurrent reaction zone 103 from the lower part of the cocurrent reaction zone 102. Within the countercurrent reaction zone 103, 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 countercurrent reaction zone 103, the reaction is complete, and it falls into the molten pool zone 101 in a molten state. The reaction gas tail gas is discharged from the furnace body through the tail gas outlet 7.

[0038] In this embodiment, a reducing gas inlet or a composite spray gun containing carbon-containing fuel and oxygen-containing combustion-supporting gas is provided at the lower part of the co-current reaction zone 102 as a reducing agent replenishment unit 9. The reducing gas inlet is used to introduce high-temperature reducing gas. The carbon-containing fuel used in the composite spray gun containing carbon-containing fuel and oxygen-containing combustion-supporting gas 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 in the furnace.

[0039] Example 2 like Figure 2 As shown in the figure, a co-current and counter-current coupled smelting furnace of this embodiment includes a furnace body 1 comprising a first furnace body 300, a second furnace body 400 and a connecting pipe 500.

[0040] The molten pool zone 101 is located at the bottom of the first furnace body 300, and the countercurrent reaction zone 103 is located at the top of the first furnace body 300.

[0041] The second furnace body 400 is connected to the first furnace body 300 by a connecting pipe 500.

[0042] The co-current reaction zone 102 is located within the second furnace body 400.

[0043] In this embodiment, the shape of the molten pool zone is consistent with the shape of the furnace body in the countercurrent reaction zone, and is an extension of it downwards; the lower opening of the furnace body in the cocurrent reaction zone is connected to the side wall of the furnace body in the countercurrent reaction zone; or, the shape of the molten pool zone is consistent with the shape of the furnace body in the cocurrent reaction zone, and is an extension of it downwards; the lower opening of the furnace body in the countercurrent reaction zone is connected to the side wall of the furnace body in the cocurrent reaction zone.

[0044] The smelting furnace body 1 includes one or more first furnace bodies 300 and one or more second furnace bodies 400. In this embodiment, there is one first furnace body 300 and one second furnace body 400.

[0045] The first furnace charge inlet 4 and the second furnace charge inlet 5 are equipped with a multi-point material distribution device, including multiple material distribution units 16 arranged above the solid reduction zone. The material distribution units are connected to the blowing tank, the equalizing tank and the material distribution bin 18 in sequence through the material distribution pipe 17.

[0046] The injection tank and / or the material distribution pipe are provided with a carrier gas inlet to inject the furnace charge into the flash furnace through the material distribution unit.

[0047] The furnace charge is a mixture of iron ore powder and flux.

[0048] The furnace charge also includes carbon powder or coal powder.

[0049] Multiple feeding units 16 are evenly arranged within the cross-section of the furnace body.

[0050] Specifically, the upper parts of the two furnace bodies are respectively equipped with a co-current zone silo and a counter-current zone silo to store smaller-diameter furnace materials and larger-diameter furnace materials.

[0051] The first furnace charge inlet 4 and the second furnace charge inlet 5 are equipped with a multi-point material distribution device, including multiple material distribution units 16 arranged above the solid reduction zone. The material distribution units are connected to the blowing tank, the equalizing tank and the material distribution bin 18 in sequence through the material distribution pipe 17.

[0052] The injection tank and / or the material distribution pipe are provided with a carrier gas inlet to inject the furnace charge into the flash furnace through the material distribution unit.

[0053] The furnace charge is a mixture of iron ore powder and flux.

[0054] The furnace charge also includes carbon powder or coal powder.

[0055] Multiple feeding units 16 are evenly arranged within the cross-section of the furnace body.

[0056] In this embodiment, the material distribution device at the first furnace material inlet 4 and the second furnace material inlet 5 is a material distribution pipe structure, which is used to send the furnace material in the material distribution bin into the furnace.

[0057] like Figure 5As shown, the fabric distribution unit is a steering wheel fabric distributor 1000; the steering wheel fabric distributor includes a feed pipe 1001, a main air supply pipe 1002, and an air supply ring pipe 1003.

[0058] The feeding pipe 1001 is connected to the rear end of the material distribution pipe 17; the air supply main pipe 1002 enters the feeding pipe through the opening in the side wall of the feeding pipe 1001 and runs in the same direction as the feeding pipe; the air supply ring pipe 1003 is located at the end of the air supply main pipe and in the lower space of the feeding pipe. The air supply ring pipe 1003 is horizontally arranged in the furnace body, and multiple air jet holes 1004 are opened circumferentially on the pipe wall of the air supply ring pipe 1003.

[0059] The jet nozzle 1004 can be disposed on the outer ring side wall of the air supply ring pipe 1003 or on the inner ring side wall of the air supply ring pipe 1003. The jet nozzle 1004 is disposed radially through the wall of the air supply ring pipe 1003 to provide lateral dispersing force for the furnace charge, thereby achieving the effect of dispersed material distribution.

[0060] To improve the uniformity of air distribution, multiple layers of annularly distributed jet holes 1004 can be provided on the air supply ring pipe 1003.

[0061] To improve fabric uniformity, in this embodiment, the air jet holes 1004 are evenly distributed in a ring along the circumference of the air supply ring pipe 1003.

[0062] like Figure 2 As shown, in this embodiment, a gas-solid separation efficiency-enhancing device is provided at the lower part of the co-current reaction zone 102. The gas-solid separation efficiency-enhancing device includes an annular baffle wall 15 disposed on the inner wall of the furnace body and a flow passage 151 disposed at the center of the annular baffle wall 15, forming a throat structure. Along the height direction of the furnace body where the counter-current reaction zone 103 is located, above the height at which the particles are in a softened state, a furnace body diameter expansion section 104 is provided. The furnace body diameter at the furnace body diameter expansion section 104 is larger than the furnace body diameter corresponding to the height at which the particles are in a solid state.

[0063] Additionally, a first dust collector 11 is included, with its inlet connected to the exhaust outlet 7. A material conveying device is located below the outlet of the first dust collector 11 and connected via a pipeline to the corresponding material distribution hopper 18 in the co-current reaction zone 102. The first dust collector 11 can be a gravity, cyclone, electrostatic precipitator, ceramic, or baghouse dust collector, used to capture smaller particle sizes of furnace materials escaping from the exhaust gas. In this embodiment, a ceramic dust collector is selected as the dust collection device.

[0064] High-temperature hydrogen gas first enters the co-current reaction zone 102 through the reducing gas inlet, moving downwards with the smaller particle size of the furnace charge. During this movement, the high-temperature hydrogen gas reacts with and exchanges heat with the furnace charge. After reaching the lower part of the furnace body, the furnace charge completes the reaction and becomes molten. Through the throat structure located at the lower part of the co-current reaction zone 102, the reaction gas is separated from the molten furnace charge. The molten furnace charge flows into the bottom molten pool zone 101.

[0065] The reactant gas and the newly added high-temperature hydrogen gas through the reducing gas and make-up heat gas inlets enter the lower part of the countercurrent reaction zone 103 from the lower part of the cocurrent reaction zone 102, moving in the opposite direction to the falling larger particle size furnace charge, and reacting and exchanging heat. An expansion section structure, namely the furnace body expansion section 104, is provided at the furnace height where the countercurrent reaction zone 103 is located to prevent the furnace charge, which is already in a softened state at this height, from contacting the furnace sidewall and sticking to it.

[0066] Larger particle size furnace charge melts and falls into the molten pool zone 101, where it melts and separates with the smaller particle size molten furnace charge, forming a slag layer and an iron layer, which are discharged through the slag outlet 3 and the iron outlet 2, respectively.

[0067] The reaction tail gas reaching the upper part of the countercurrent reaction zone is discharged from the furnace body through tail gas outlet 7 and enters the ceramic dust collector connected thereto. The escaped furnace material separated by the ceramic dust collector is sent through the pipeline to the material bin of the cocurrent reaction zone and enters the cocurrent reaction zone 102 for smelting.

[0068] Example 3 like Figure 3 As shown, in this embodiment, the forward and reverse coupled flash furnace includes a third furnace body 600, a fourth furnace body 700, and a horizontal molten pool 800.

[0069] The third furnace body 600 and the fourth furnace body 700 are respectively located at both ends of the horizontal molten pool 800. The third furnace body 600 and the fourth furnace body 700 are respectively connected to the horizontal molten pool 800. The third furnace body 600 and the fourth furnace body 700 are cylindrical furnace bodies. The lower part of the furnace body 600 where the co-current reaction zone 102 is located and the furnace body 700 where the counter-current reaction zone 103 is located are connected to the horizontal molten pool 800. The horizontal molten pool 800 is rectangular.

[0070] The lower part of the molten pool zone 101 is a layer of molten iron, and the upper part is a layer of slag. An iron tapping port 2 is provided in the direction of the height of the molten iron layer, and a slag tapping port 3 is provided in the direction of the height of the slag layer. The molten furnace charge that has completed the reaction in the co-current reaction zone 102 and the counter-current reaction zone 103 falls into the molten pool zone 101, where the final melting and separation is completed, resulting in a layer of molten iron and a layer of slag, which are then discharged from the furnace body separately.

[0071] In this embodiment, a co-current zone hopper is provided at the top of the furnace body where the co-current reaction zone 102 is located. Smaller particle size furnace charge from the hopper is sprayed into the co-current reaction zone through a spray gun to react with the high-temperature reducing gas in the co-current reaction zone 102. The molten furnace charge after the reaction is completed falls into the horizontal molten pool 800 below.

[0072] like Figure 6 As shown, the spray gun, i.e. the material distribution unit 16, is a side air material distributor 2000; the side air material distributor 2000 includes a nozzle 2001 disposed on the furnace body and furnace top, the nozzle opening facing downward and inclined.

[0073] A feeding channel 2002 is provided above the nozzle, and the feeding channel 2002 is connected to the material distribution pipe 17.

[0074] The nozzle sidewall is provided with a fabric air channel 2003, and the outlet of the fabric air channel is inclined toward the nozzle opening. The fabric air channel 2003 is connected to the fabric air system.

[0075] A countercurrent zone hopper is installed at the top of the furnace body where the countercurrent reaction zone 103 is located, such as... Figure 7 As shown, the furnace charge is evenly sprayed into the internal space of the countercurrent reaction zone 103 of the furnace body through the U-shaped distributor 3000. The furnace charge reacts and exchanges heat with the high-temperature reducing gas in the furnace, and the molten furnace charge that has completed the reaction falls into the horizontal molten pool 800 below.

[0076] like Figure 7 As shown, the fabric unit is a U-shaped fabric feeder 3000; the U-shaped fabric feeder 1000 includes a U-shaped tube 3001 connected to the fabric tube 17, the end of the U-shaped tube is bent upward to form a discharge port, and the discharge port is set vertically upward or inclined upward.

[0077] A ore baffle 3002 is installed on the charge injection path of the U-shaped tube 3001 outlet, and the ore baffle 3002 is fixedly installed inside the furnace body 1 of the smelting furnace.

[0078] To prevent blockages in individual distribution pipes, each distribution pipe is equipped with two venting air inlets. These inlets connect to venting pipe 3003, through which venting air is introduced. This allows for auxiliary gas supply during normal production and immediate purging and unblocking upon detection of a blockage. Flow and pressure gauges are installed on the venting air pipes for real-time monitoring and location of blocked sections.

[0079] In this embodiment, the lower part of the silo is connected to the equalizing tank via a valve, and the equalizing tank is connected to the injection tank via a valve located at its lower part. An air carrier pipe is installed on the injection tank, and the initial ends of multiple material distribution pipes are connected to the lower part of the injection tank.

[0080] A reducing gas inlet and a combustion chamber are provided on the upper side wall of the furnace body where the co-current reaction zone 102 is located. Pulverized coal and oxygen are incompletely combusted in the combustion chamber to generate high-temperature reducing flue gas, which provides heat and some reducing gas. Hydrogen obtained by dust removal and transformation of the tail gas in the furnace enters the furnace through the reducing gas inlet, comes into contact with the high-temperature flue gas to raise its temperature, and reacts and exchanges heat with the falling furnace charge at the same time.

[0081] In addition, the reducing agent supply unit 6 includes a reducing gas inlet, which can be directly connected to the combustion chamber 8. The combustion chamber 8 is a cavity protruding from the furnace body, with a combustion nozzle at one end along the axial direction and a reducing gas outlet at the other end, which is connected to the reducing gas inlet on the side wall of the furnace body. The combustion chamber 8 consists of a steel plate shell, an inner refractory lining, and water-cooled walls at higher temperatures.

[0082] The combustion nozzle is equipped with a fuel inlet and an auxiliary combustion gas inlet, which are connected to a fuel supply device 18 and an oxygen supply device 19, respectively. The fuel is pulverized coal, coal gas, or natural gas, and the auxiliary combustion gas is pure oxygen or oxygen-enriched gas.

[0083] like Figures 8-10 As shown, at least one reducing gas injection inlet is provided on the combustion end and / or side wall of the combustion chamber 8. The reducing gas injected through the reducing gas injection inlet flows closely to the circumferential side wall of the combustion chamber 8 to form an air curtain.

[0084] Specifically, such as Figure 8 As shown, when the reducing gas injection inlet is located on the inner wall of the combustion chamber, there are multiple reducing gas injection inlets. These multiple reducing gas injection inlets are arranged around the circumferential wall surface of the inner wall of the combustion chamber 8, so that the reducing gas to be heated injected forms a complete cooling air curtain on the inner wall of the combustion chamber 8.

[0085] like Figure 9 As shown, when the reducing gas injection inlet is located at the combustion end of the combustion chamber 8, there are multiple reducing gas injection inlets. These multiple reducing gas injection inlets are arranged around the combustion nozzle and distributed in a ring along the axis of the combustion chamber 8, so that the reducing gas to be heated ejected forms a complete cooling gas curtain on the inner wall of the combustion chamber 8.

[0086] like Figure 10 As shown, the reducing gas injection inlet forms an angle with the axis of the combustion chamber, creating a spiral cooling air curtain that increases the travel distance of the reducing gas within the combustion chamber.

[0087] The reducing gas inlet or the combustion chamber 8 connected to the reducing gas inlet is also connected to a reducing gas supply device 10.

[0088] The reducing gas supply device is one or a combination of a coal gasifier or coal-to-hydrogen device, an electrolytic hydrogen device, a coke oven gas-to-hydrogen device, a methanol-to-hydrogen device, and an ammonia-to-hydrogen device.

[0089] In this embodiment, a combustion chamber 8 is provided on the furnace sidewall at the lower part of the co-current reaction zone 102 and the counter-current reaction zone 103 as a reducing agent replenishment unit. The pulverized coal and oxygen are incompletely burned in the combustion chamber to generate high-temperature reducing flue gas, which replenishes the heat and reducing agent required for the reaction.

[0090] Figure 3 In the process, after dust removal, the exhaust gas undergoes a conversion process to convert carbon monoxide into hydrogen, which is then returned to the furnace. Hydrogen has a better reducing potential, making it preferable for reduction. The conversion process shown in the attached diagram includes hydrogen conversion, carbon dioxide removal, and dehydration (not shown in the diagram). For further explanation... Figure 4 Some aspects have been elaborated and illustrated in the attached diagram, and a solution for utilizing heat from exhaust gases has been added.

[0091] like Figure 4 As shown, the exhaust gas in the furnace is discharged from the furnace body through the exhaust gas outlet 7. The exhaust gas outlet is connected to the first dust collector 11, which collects the smaller particle size furnace material that escapes in the countercurrent reaction zone 103 and transports it to the cocurrent zone silo through the pipeline.

[0092] The air outlet of the first dust collector 11 is connected to the hot side inlet of the heat exchange device 12.

[0093] The hot side outlet of heat exchange device 12 is connected to carbon dioxide removal device 13 and dehydration device in sequence. The outlet of dehydration device is connected to the inlet of circulating fan. The outlet of circulating fan is connected to the cold side inlet of heat exchange device 12. The cold side outlet of heat exchange device 12 is connected to the inlet of combustion chamber 8 or plasma heating device.

[0094] The discharge ports of the first dust collector 10 and the second dust collector 13 are connected to the material hopper of the material distribution device in the co-current reaction zone 102.

[0095] A sulfur dioxide removal device is installed between the hot side outlet of the heat exchange device 12 and the second dust collector.

[0096] A hydrogen conversion device 14 is provided between the outlet of the second dust collector and the carbon dioxide removal device 13. The hydrogen conversion device 14 converts the remaining carbon monoxide in the tail gas into hydrogen. After the carbon dioxide removal device 13 removes the carbon dioxide in the gas, it is sent back into the furnace through the conveying pipeline route of the reducing gas inlet.

[0097] In this embodiment, the shape of the molten pool region 101 is elongated in the horizontal direction to form an extension section 1011, and a supplementary heating flue gas and / or thermal reducing gas inlet is provided at the elongated end of the molten pool region 101.

[0098] The tapping port 2 and the slag outlet 3 are located on the elongated end side of the molten pool zone 101.

[0099] Example 4 like Figure 11 As shown, the difference from Embodiment 1 is that the air supply main pipe 1002 is located outside the discharge pipe 1001 and runs downward together with the discharge pipe.

Claims

1. A reverse-coupling flash smelting furnace, characterized in that: The furnace body (1) includes a smelting furnace body (1), which includes a molten pool zone (101) located at the bottom of the cavity and a co-current reaction zone (102) and a counter-current reaction zone (103) located above the molten pool zone (101). The co-current reaction zone (102) and counter-current reaction zone (103) 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 area (101) is a molten iron layer, and the upper part of the molten pool area (101) is a slag layer. The sidewall of the molten pool area (101) is provided with an iron outlet (2) in the height range of the molten iron layer and a slag outlet (3) in the height range of the slag layer. The co-current reaction zone (102) and the counter-current reaction zone (103) are both independent vertical cavities, and the lower part of the co-current reaction zone (102) and the lower part of the counter-current reaction zone (103) are interconnected. The top of the furnace body where the co-current reaction zone (102) is located is provided with a first charge inlet (4), and the top of the furnace body where the counter-current reaction zone (103) is located is provided with a second charge inlet (5). A reducing agent supply unit (6) is provided on the upper part of the furnace body where the co-current reaction zone (102) is located. The reducing agent supply unit is used to provide the reducing gas and heat required for the reaction. The countercurrent reaction zone (103) is located on the upper part of the furnace body with an exhaust gas outlet (7).

2. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: The reducing agent supply unit (6) includes a reducing gas inlet and a gas heating unit. The reducing gas inlet is located on the side wall of the furnace body (1) of the smelting furnace and is connected to the gas heating unit. The gas heating unit is used to heat the reducing gas; Preferably, the gas heating unit is a combustion chamber (8) or a plasma heating device; Preferably, the combustion chamber (8) is a cavity protruding from the furnace body, with a combustion nozzle at one end of the combustion chamber along the axial direction and a reducing gas outlet at the other end, the reducing gas outlet being connected to the reducing gas inlet on the side wall of the furnace body; The combustion nozzle is equipped with a fuel inlet and an auxiliary combustion gas inlet; At least one reducing gas injection inlet is provided on the combustion end and / or side wall of the combustion chamber (8), and the reducing gas supplied by the reducing gas injection inlet flows closely against the circumferential side wall of the combustion chamber (8) to form an air curtain; Preferably, the reducing gas injection inlet forms an angle with the axis of the combustion chamber (8) to form a spiral gas curtain; The reducing agent supply unit (6) may include a reducing gas inlet and a supplementary heating gas inlet provided on the side wall of the smelting furnace body (1), or may include a reducing gas inlet and a supplementary heating gas raw material supply device provided on the side wall of the smelting furnace body (1). The reducing gas inlet is used to supply room temperature reducing gas or preheated reducing gas, and the supplementary heating gas inlet or supplementary heating gas raw material supply device is used to provide heat. Or the reducing agent supply unit (6) includes a composite spray gun containing carbon fuel and oxygen-containing combustion gas installed on the side wall of the smelting furnace body (1), which generates reducing hot flue gas through incomplete combustion in the furnace; Preferably, the carbon-containing fuel is pulverized coal, coal gas, or natural gas, and the oxygen-containing combustion-supporting gas is pure oxygen or oxygen-enriched gas.

3. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: It also includes a reducing agent replenishment unit (9) and / or a heat replenishment unit; The reducing agent replenishment unit (9) and the heating unit are located in the middle and / or lower part of the co-current reaction zone (102), or in the lower part of the counter-current reaction zone (103); The reducing agent replenishment unit (9) is a reducing gas inlet or a composite spray gun containing carbon fuel and oxygen-containing combustion-supporting gas; The heating unit is a hot flue gas inlet or a heating gas raw material supply device.

4. The reverse-coupling flash smelting furnace as described in claim 2, characterized in that: The inlet end of the reducing gas inlet, or the inlet end of the plasma heating device or combustion chamber (8) connected to the reducing gas inlet, is also connected to a reducing gas supply device (10). Preferably, the reducing gas supply device is one or a combination of a coal gasifier or coal-to-hydrogen device, an electrolytic hydrogen device, a coke oven gas-to-hydrogen device, a methanol-to-hydrogen device, and an ammonia-to-hydrogen device.

5. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: A furnace body expansion section (104) is provided at the height of the furnace body near the entrance to the softening and reduction zone where the co-current reaction zone (102) and / or counter-current reaction zone (103) are located. Preferably, the maximum flow area of ​​the furnace body expansion section (104) is 10% to 50% larger than the flow area of ​​the upper furnace body, and the expansion section extends to the liquid zone of the furnace charge.

6. The reverse-coupling flash smelting furnace as described in claim 2, characterized in that: The exhaust outlet (7) is connected to the first dust collector (11), and the air outlet of the first dust collector (11) is connected to the hot side inlet of the heat exchange device (12). The heat exchange device (12) has its hot side outlet connected to the carbon dioxide removal device (13) and the dehydration device in sequence. The dehydration device outlet is connected to the circulating fan inlet. The circulating fan outlet is connected to the cold side inlet of the heat exchange device (12). The heat exchange device (12) has its cold side outlet connected to the combustion chamber (8) or the plasma heating device inlet. The discharge ports of the first dust collector (10) and the second dust collector (13) are connected to the material hopper of the material distribution device in the co-current reaction zone (102); Preferably, a sulfur dioxide removal device is provided between the hot side outlet of the heat exchange device (12) and the second dust collector; Preferably, a hydrogen conversion device (14) is provided between the outlet of the second dust collector and the carbon dioxide removal device (13).

7. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: A gas-solid separation efficiency improvement device is provided at the lower part of the co-current reaction zone (102). The gas-solid separation efficiency improvement device includes an annular baffle (15) provided on the inner wall of the furnace body and a flow passage (151) provided at the center of the annular baffle (15).

8. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: The furnace body (1) of the smelting furnace includes a vertical furnace body (100). The vertical furnace body (100) has a vertical partition wall (200) connected to the side wall of the furnace body above the inner cavity, which divides the space above the inner cavity of the furnace body into a co-current reaction zone (102) and a counter-current reaction zone (103). The molten pool zone (101) is located at the bottom of the vertical furnace body (100); Preferably, the vertical furnace body (100) has the same shape on the top and bottom.

9. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: The furnace body (1) of the smelting furnace includes a first furnace body (300), a second furnace body (400) and a connecting pipe (500). The molten pool zone (101) is located at the bottom of the first furnace body (300); The second furnace body (400) is connected to the side wall of the first furnace body (300) by a connecting pipe (500); Preferably, the furnace body (1) of the smelting furnace includes one or more first furnace bodies (300) and / or one or more second furnace bodies (400).

10. The reverse-coupling flash smelting furnace as described in claim 1, characterized in that: The furnace body (1) of the smelting furnace includes a third furnace body (600), a fourth furnace body (700) and a horizontal molten pool (800). The third furnace body (600) and the fourth furnace body (700) are respectively located at both ends of the horizontal molten pool (800), and the third furnace body (600) and the fourth furnace body (700) are respectively connected to the horizontal molten pool (800).

11. The reverse-coupling flash furnace as described in claim 1, characterized in that: The shape of the molten pool region (101) is elongated in the horizontal direction to form an extension section (1011), and a supplementary heating flue gas and / or thermal reducing gas inlet is provided at the elongated end of the molten pool region (101); The tapping port (2) and slag outlet (3) are located on the elongated end side of the molten pool zone (101).

12. The reverse-coupling flash furnace as described in claim 1, characterized in that: The first furnace charge inlet (4) and the second furnace charge inlet (5) are equipped with a multi-point material distribution device, including multiple material distribution units (16) set above the solid reduction zone. The material distribution units are connected to the blowing tank, the equalizing tank and the material distribution bin (18) in sequence through the material distribution pipe (17). The injection tank and / or the material distribution pipe are provided with a carrier gas inlet to inject the furnace charge into the flash furnace through the material distribution unit. Preferably, the furnace charge is a mixture of iron ore powder and flux; Preferably, the furnace charge further includes carbon powder or coal powder; Preferably, multiple fabric units (16) are evenly arranged within the cross-section of the furnace body.

13. The reverse-coupling flash furnace as described in claim 12, characterized in that: The fabric distribution unit (16) is a steering wheel fabric distributor (1000); the steering wheel fabric distributor includes a feed pipe (1001), a main air supply pipe (1002) and an air supply ring pipe (1003). The feed pipe (1001) is connected to the rear end of the fabric distribution pipe (17); the air supply main pipe (1002) enters the feed pipe through the opening in the side wall of the feed pipe (1001) and runs in the same direction as the feed pipe, or the air supply main pipe (1002) is located outside the feed pipe (1001) and runs downward together with the feed pipe; the air supply ring pipe (1003) is located at the end of the air supply main pipe and in the lower space of the feed pipe, and multiple air jet holes (1004) are opened circumferentially on the pipe wall of the air supply ring pipe (1003).

14. The reverse-coupling flash furnace as described in claim 12, characterized in that: The material distribution unit (16) is a side air distributor (2000); the side air distributor (2000) includes a nozzle (2001) disposed on the furnace top of the furnace body, the nozzle opening is downward and inclined; A feeding channel (2002) is provided above the nozzle, and the feeding channel (2002) is connected to the material distribution pipe (17); The nozzle sidewall is provided with a fabric air channel (2003), and the outlet of the fabric air channel is inclined toward the nozzle opening.

15. The reverse-coupling flash furnace as described in claim 12, characterized in that: The fabric unit (16) is a U-shaped fabric feeder (3000); the U-shaped fabric feeder (3000) includes a U-shaped tube (3001) connected to the fabric tube (17), the end of the U-shaped tube is bent upward to form a discharge port, and the discharge port is set vertically upward or inclined upward. Preferably, a ore baffle (3002) is provided on the furnace charge injection path of the U-shaped tube outlet, and the ore baffle (3002) is fixedly installed inside the furnace body (1) of the smelting furnace.

16. The reverse-coupling flash furnace as described in claim 1, characterized in that: It also includes a furnace charge sorting device, which is an air classifier or a dry airflow screening device; The sorting device is connected to a main silo. The sorting device separates the furnace charge into two parts: a larger particle size and a smaller particle size, which are then sent to the corresponding silos in the countercurrent reaction zone and the cocurrent reaction zone, respectively.

17. A reverse-coupling flash smelting method, employing the reverse-coupling flash smelting furnace as described in any one of claims 1 to 16, characterized in that, The process includes the following steps: Before feeding, the furnace charge is sorted into co-current reactant and counter-current reactant according to the particle size. The co-current reactant is fed into the co-current reaction zone (102) from the first furnace charge inlet (4), and the counter-current reactant is fed into the counter-current reaction zone (103) from the second furnace charge inlet (5). The reducing gas is introduced into the furnace from the upper part of the co-current reaction zone (102), or is prepared in the upper part of the co-current reaction zone (102); The reducing gas and the co-current reactant move downwards in the co-current reaction zone (102) and react and exchange heat. When they reach the lower part of the co-current reaction zone (102), the furnace charge falls into the molten pool zone (101) in a molten state, while the reactant gas enters the lower part of the countercurrent reaction zone (103) from the lower part of the co-current reaction zone (102) and moves upwards along the countercurrent reaction zone (103), moving in the opposite direction to the countercurrent reactant moving downwards in the countercurrent reaction zone (103), and continues to react and exchange heat. After the countercurrent reaction material reaches the lower part of the countercurrent reaction zone (103), it completes the reaction and falls into the molten pool zone (101) in a molten state; the reduction tail gas is discharged through the tail gas outlet (7) set at the upper part of the furnace body of the countercurrent reaction zone (103); The molten material falling into the molten pool zone (101) melts and separates under the action of gravity, forming an iron layer and a slag layer, which are discharged from the furnace through the tapping port (2) and the slag tapping port (3), respectively.

18. The reverse-coupling flash smelting method as described in claim 17, characterized in that: The reducing gas is at least one or a combination of hydrogen, carbon monoxide, and methane. Preferably, a plasma device is used to heat the reducing gas to the temperature required for the reaction.

19. The reverse-coupling flash smelting method as described in claim 17, characterized in that: Powdered coal and oxygen are injected into the co-current reaction zone (102) to react, generating reducing gas CO and releasing heat.

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