Electric smelting furnace with suspension side-blown and method for smelting iron-based minerals

Abstract

The present application provides a kind of suspension side-blown electric heat smelting furnace and iron-based mineral smelting method.The suspension side-blown electric heat smelting furnace includes integrated suspension reaction tower and sedimentation tank, the top of suspension reaction tower has the entrance of to-be-smelted mineral material, and the top and / or side are also provided with a plurality of first spray guns, the first spray gun is independently connected with at least one of reducing agent supply unit, fuel supply unit or oxygen-containing gas supply unit, and suspension reaction tower is used for making to-be-smelted mineral material to carry out suspension smelting reaction;Sedimentation tank has horizontal structure, along the length direction of sedimentation tank, sedimentation tank includes side-blown area and electric heating area which are communicated, the top of side-blown area is directly communicated with the bottom of suspension reaction tower;Side wall of side-blown area is provided with a plurality of second spray guns, and electric heating area is provided with heating electrode.The present application solves the problems of energy quality imbalance, high iron content in slag and low reaction efficiency in the current flash smelting process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metallurgy, in particular to a suspension side-blown electric heat smelting furnace and a smelting method of iron-based minerals. BACKGROUND

[0002] At present, in the non-ferrous and ferrous metallurgical industry, suspension / rotary suspension smelting belongs to modern intensified smelting process, and the smelting equipment thereof is called flash smelting furnace (or rotary suspension furnace) in the industry, which can be applied to the smelting of iron, copper, nickel, lead, solid waste and other metals.

[0003] Taking iron smelting as an example, iron smelting process can be divided into two categories: blast furnace iron smelting and non-blast furnace iron smelting, among which blast furnace iron smelting accounts for the main part, and non-blast furnace iron smelting mainly includes direct reduction and smelting reduction technologies. Direct reduction processes include rotary kiln-electric furnace, rotary hearth-electric furnace and shaft furnace-electric furnace, etc. Smelting reduction processes include HIsmelt, Corex and Finex, etc. The steel production process in China mainly adopts the long process of coking-sintering-blast furnace-converter, and the iron smelting process based on coking-sintering-blast furnace accounts for 60% of the total energy consumption, and the production cost accounts for 70% of the cost per ton of steel, and the pollutant emission accounts for 90% of the total amount. Therefore, the blast furnace iron smelting process has problems such as long process, high energy consumption and serious pollution, and is strongly dependent on metallurgical coke. The development of non-blast furnace iron smelting technology is mainly due to the long process of blast furnace smelting process, the use of sinter or pellet and coke in the smelting process, the shortage of coking coal resources, and the high energy consumption and serious pollution of coking process.

[0004] Direct use of fine ore can save the balling process and the corresponding energy consumption, and reduce environmental pollution. The particle size of fine ore is small, and the specific surface area is large. In the reduction process, fine ore can be more fully contacted with reducing gas, thereby intensifying the mass and heat transfer process between iron oxide and gas, thereby greatly improving the reduction kinetics conditions and improving production efficiency, and fundamentally solving the problems of high energy consumption and serious environmental pollution in production process. Based on this background, the flash smelting furnace emerged as the times require. For example:

[0005] A flash smelting furnace with a side-blown bath section is disclosed in Chinese patent application No. 201610280696.7, which comprises a reaction tower, at least one bath is arranged at the lower part of the reaction tower, each bath is provided with a side-blown bath section with an inner width less than 3 meters, a side-blown arrangement is arranged at the side of the side-blown bath section, a slag discharge port is arranged at the end of the side-blown bath section, and the side-blown bath section is located between the slag discharge port and the reaction tower; the flash smelting furnace further comprises an ascending flue which is connected with the reaction tower through the bath. The flash smelting furnace is provided with the side-blown bath section with an inner width less than 3 meters, so that each part of the bath can be directly affected by the side blowing, especially the central part can be blown through, the side blowing supplies heat to the bath, the bath forms a liquid melt environment with good fluidity, thereby realizing the functions of slag making, sedimentation and discharge of slag and metal, etc. Meanwhile, the side blowing arrangement can also provide reducing agent for the bath to complete the reduction of the remaining metal oxide in the slag layer, thereby improving the recovery rate of the metal.

[0006] A flash smelting method of iron is disclosed in Chinese patent application No. 201210179226.3, in which powdered dry iron ore with a large specific surface area is directly injected into a hot reaction tower space through a nozzle arranged at the top of the reaction tower together with fuel and oxygen at a high speed in a floating state, and is rapidly heated to about 1200℃, during which the high-valence iron oxides in the iron ore are partially reduced to low-valence iron oxides and part of metallic iron, and then falls into a bath in the lower part of the reaction tower. There is a layer of about 1550℃ hot coke or other carbon filter layer in the upper part of the bath, and a side-blown nozzle for pulverized coal or other reducing agent is arranged on the side wall of the filter layer of the bath, and high-temperature or normal-temperature oxygen-enriched air is used. The low-valence iron oxides are further reduced to metallic iron in the filter layer. The generated metallic iron and slag are layered in the bath and are continuously or periodically discharged. The generated flue gas is discharged after being combusted in a waste heat boiler and dedusted, or is sent to a hot blast furnace as fuel.

[0007] A dry and reduction-granulation flash iron smelting device and method are disclosed in Chinese patent application No. 201410163342.5, in which the wet concentrate in a pre-reduction drying tower is dried and pre-reduced by using the high-temperature flue gas generated in a reduction tower, and then the dry concentrate discharged from the pre-reduction drying tower is directly conveyed into the reduction tower for reduction. In this way, the high-temperature flue gas can be reused, and energy loss and environmental pollution caused by direct discharge of the high-temperature flue gas can be avoided, thereby significantly improving energy reuse, avoiding energy loss and environmental pollution caused by direct discharge of the high-temperature flue gas, and significantly improving energy utilization rate and iron smelting efficiency.

[0008] The double-tower flash iron-making furnace and the iron-making method disclosed in the Chinese patent application No. 201410163977.5 include: a furnace bottom, the furnace bottom defines a molten pool inside; a first reduction tower, the first reduction tower defines a first tower cavity inside; a second reduction tower, the second reduction tower defines a second tower cavity inside; the lower ends of the first reduction tower and the second reduction tower are connected with the furnace bottom; a partition wall is arranged in the second tower cavity and divides the second tower cavity into an ascending flue and a reduction channel; the first tower cavity is communicated with the lower end of the ascending flue, and the upper end of the ascending flue is communicated with the upper end of the reduction channel. The double-tower flash iron-making furnace has the advantages of low investment, high capacity and energy saving. The iron-making method includes: spraying dry concentrate, fuel including coke, pulverized coal and oxygen into the first tower cavity through a concentrate nozzle; adding dry concentrate and flux into the reduction channel through a feeding port; and reducing the dry concentrate in the reduction channel by the flue gas in the first tower cavity. The method has high efficiency and low cost.

[0009] The traditional flash furnace includes three parts, a reaction tower, a settling tank and an ascending flue. In the specific smelting process, the dry powder mixture with water content less than 0.3% and the reaction gas are sprayed into the reaction tower at high speed through the nozzle. Due to the huge specific surface area advantage of the powder material, the physical and chemical reactions of the mixture, such as heating, melting, oxidation / reduction and slagging, occur rapidly, and the formed superheated melt falls into the settling tank to continue the physical and chemical reactions which are not completed in the reaction tower, and separates into metal products and slag. The flue gas and smoke generated in the reaction process are discharged through the ascending flue. However, for the traditional flash furnace, the chemical kinetics condition in the settling tank is poor, the molten pool is calm and has no agitation, so the speed of the continued physical and chemical reactions is very slow. This makes the slag discharged from the settling tank contain a relatively high amount of valuable metals. With the continuous production of various production plants, the amount of valuable metals in the slag is gradually increasing, resulting in a huge waste of resources. In addition, more importantly, when processing iron-based minerals, there are problems such as mismatch of energy and quality, low reduction rate and high iron content in the slag.

[0010] In addition, the poor chemical kinetics condition makes it easy for high-melting-point substances to deposit in the settling tank to form a furnace knot, which in turn reduces the volume of the settling tank, which in turn further worsens the depletion and settlement of valuable metals. After the formation of the furnace knot, there is no effective means to eliminate it. The furnace knot around the metal discharge port makes it difficult to burn the hole, and the discharge of the slag needs to be more frequent, increasing the pressure of the on-site operation.

[0011] Therefore, the present application is proposed. SUMMARY

[0012] The main purpose of the present application is to provide a suspension side-blown electric heating smelting furnace and a smelting method of iron-based minerals, to solve the problems of energy and quality imbalance, high iron content in the slag and low reaction efficiency in the smelting process of the flash furnace in the prior art.

[0013] To achieve the above object, according to one aspect of the present application, a suspension side-blown electric smelting furnace is provided, which comprises a suspension reaction tower and a settling tank arranged integrally, and further comprises a reducing agent supply unit, a fuel supply unit and an oxygen-containing gas supply unit; wherein: the top of the suspension reaction tower is provided with a raw material injection port, and the top and / or side thereof is further provided with a plurality of first injection lances, each of which is independently connected to at least one of the reducing agent supply unit, the fuel supply unit or the oxygen-containing gas supply unit, and the suspension reaction tower is used for carrying out a suspension smelting reaction on the raw material; the settling tank has a horizontal structure, and along the length direction of the settling tank, the settling tank comprises a side-blown zone and an electric heating zone which are connected in series, and the top of the side-blown zone is directly connected to the bottom of the suspension reaction tower; a plurality of second injection lances are arranged on the side wall of the side-blown zone, and the electric heating zone is provided with heating electrodes; each of the second injection lances is independently connected to at least one of the reducing agent supply unit, the fuel supply unit and the oxygen-containing gas supply unit.

[0014] Further, the suspension reaction tower is sequentially divided into a preheating zone, a reduction zone and a melting zone from top to bottom, and the plurality of first injection lances comprise at least three groups, each group of first injection lances comprises at least two first injection lances, and at least one group of first injection lances is arranged in each of the preheating zone, the reduction zone and the melting zone.

[0015] Further, the first injection lances arranged in the preheating zone are connected to the fuel supply unit and the oxygen-containing gas supply unit; wherein, the first injection lances arranged in the preheating zone are double-channel injection lances, the inner channel of which is connected to the oxygen-containing gas supply unit, and the outer channel of which is connected to the fuel supply unit; or, the first injection lances arranged in the preheating zone are single-channel injection lances, a part of which is connected to the oxygen-containing gas supply unit, and the other part of which is connected to the fuel supply unit; a part of the first injection lances arranged in the reduction zone are single-channel injection lances and are connected to the reducing agent supply unit, and the other part thereof are double-channel injection lances, the inner channel of which is connected to the oxygen-containing gas supply unit, and the outer channel of which is connected to the fuel supply unit; or, the first injection lances arranged in the reduction zone are triple-channel injection lances, the inner channel of which is connected to the reducing agent supply unit, the middle channel of which is connected to the oxygen-containing gas supply unit, and the outer channel of which is connected to the reducing agent supply unit or the fuel supply unit; a part of the first injection lances arranged in the melting zone are single-channel injection lances and are connected to the reducing agent supply unit, and the other part thereof are double-channel injection lances, the inner channel of which is connected to the oxygen-containing gas supply unit, and the outer channel of which is connected to the fuel supply unit; or, the first injection lances arranged in the melting zone are triple-channel injection lances, the inner channel of which is connected to the reducing agent supply unit, the middle channel of which is connected to the oxygen-containing gas supply unit, and the outer channel of which is connected to the reducing agent supply unit or the fuel supply unit.

[0016] Further, the suspension side-blown electric smelting furnace further comprises an updraft flue arranged at the top of the side-blown zone and communicated with the side-blown zone, and the updraft flue is arranged at the end of the side-blown zone close to the electric heating zone, and the suspension reaction tower is arranged at the end of the side-blown zone away from the electric heating zone.

[0017] Further, the updraft flue is also integrally arranged with the settling tank, and the side wall of the updraft flue close to the electric heating zone extends into the settling tank to form a partition wall between the side-blown zone and the electric heating zone.

[0018] Further, each of the second lances is independently connected with at least one of the reducing agent supply unit, the fuel supply unit and the oxygen-containing gas supply unit.

[0019] Further, the second lances are three-channel integrated lances, the inner channel of which is connected with the reducing agent supply unit, the middle channel of which is connected with the oxygen-containing gas supply unit, and the outer channel of which is connected with the reducing agent supply unit or the fuel supply unit; or, part of the second lances are single-channel lances connected with the reducing agent supply unit, and the other part of the second lances are double-channel lances, the inner channel of which is connected with the oxygen-containing gas supply unit, and the outer channel of which is connected with the reducing agent supply unit or the fuel supply unit.

[0020] Further, the top of the side-blown zone is further provided with a plurality of heat supplement burners.

[0021] Further, along the length direction of the settling tank, the length ratio of the side-blown zone to the electric heating zone is 0.5-3:1; and / or, the bottom wall of the side-blown zone is flush with the bottom wall of the electric heating zone, or the bottom wall of the electric heating zone is lower than the bottom wall of the side-blown zone; and the top height of the side-blown zone is higher than the top height of the electric heating zone.

[0022] According to another aspect of the present application, there is also provided a smelting method of iron-based minerals, which smelts the iron-based minerals by using the above-mentioned suspension side-blown electric smelting furnace, and the smelting method comprises the following steps: iron-based minerals and flux are sprayed into the suspension reaction tower from the top of the tower through the smelting material spraying inlet with compressed air or inert gas as the carrier, and at least one of reducing agent, fuel or oxygen-containing gas is sprayed into the suspension reaction tower through the first lance to make the iron-based minerals perform a suspension smelting reaction; the smelting melt obtained by the suspension smelting reaction directly falls into the side-blown zone of the settling tank through the bottom of the suspension reaction tower, and at least one of reducing agent, fuel or oxygen-containing gas is further sprayed into the slag layer of the side-blown zone through the second lance to make the smelting melt perform a bath smelting reaction; the smelting product obtained by the bath smelting reaction enters the electric heating zone of the settling tank, and performs electric heating reduction under the heating of the heating electrode to obtain molten iron and slag.

[0023] Further, the suspension reaction tower is sequentially divided into a preheating zone, a reduction zone and a melting zone from top to bottom, and during the suspension smelting reaction process, the temperature of the preheating zone is controlled to be 600-1000℃, the temperature of the reduction zone is controlled to be 1000-1450℃, and the temperature of the melting zone is controlled to be 1450-1650℃; preferably, fuel and oxygen-containing gas are sprayed into the preheating zone through the first lance arranged in the preheating zone to control the temperature of the preheating zone; fuel, oxygen-containing gas and reducing agent are sprayed into the reduction zone through the first lance arranged in the reduction zone to control the temperature of the reduction zone and make the iron-based mineral undergo preliminary suspension smelting reaction; fuel, oxygen-containing gas and reducing agent are sprayed into the melting zone through the first lance arranged in the melting zone to control the temperature of the melting zone, make the iron-based mineral undergo further suspension smelting reaction, and make the obtained smelting product melt to form a smelting melt.

[0024] Further, during the bath smelting reaction process, the temperature of the side-blown zone is controlled to be 1550-1650℃; preferably, the second lance is a three-channel integrated lance, reducing agent is sprayed into the slag layer of the side-blown zone through the inner channel of the second lance, oxygen-containing gas is sprayed into the slag layer of the side-blown zone through the middle channel of the second lance, and reducing agent or fuel is sprayed into the slag layer of the side-blown zone through the outer channel of the second lance; or, among the plurality of second lances, part of them are single-channel lances for spraying reducing agent into the slag layer of the side-blown zone, and the other part of them are double-channel lances, oxygen-containing gas is sprayed into the slag layer of the side-blown zone through the inner channel of the double-channel lances, and reducing agent or fuel is sprayed into the slag layer of the side-blown zone through the outer channel of the double-channel lances; preferably, the side-blown zone is heated by the heat-supply burner to maintain the temperature of the side-blown zone; preferably, during the bath smelting reaction process, coke is added into the bath.

[0025] Further, during the electrothermal reduction process, the temperature of the electrothermal zone is controlled to be 1550-1780℃; preferably, during the electrothermal reduction process, blocky reducing agent is added into the electrothermal zone through the reducing agent feeding port at the top of the electrothermal zone, or reducing agent is sprayed into the electrothermal zone through the third lance.

[0026] Further, the blocky reducing agent is one or more of blocky coal, coke, petroleum coke, silicon-manganese, silicon-iron, manganese-iron; the sprayed reducing agent is one or more of pulverized coal, coke powder, petroleum coke powder, graphite powder, natural gas, coal gas, coal gas, hydrogen; the fuel is one or more of natural gas, heavy oil, coal powder, coal gas, coal gas, hydrogen, coke powder, gasoline; the oxygen-containing gas is oxygen-enriched air or oxygen; the iron-based mineral is one or more of iron concentrate, vanadium-titanium magnetite, sea sand ore, high-phosphorus iron ore, laterite nickel ore, iron-containing solid waste, preferably the iron-containing solid waste is one or more of red mud, copper smelting slag, copper lean slag; the flux is calcareous flux, preferably unslaked lime and / or limestone; preferably, the iron-based mineral and the flux are proportioned according to the binary basicity CaO / SiO2=0.5-1.5.

[0027] Further, before the iron-based minerals and flux are sprayed through the smelting material spraying inlet, the smelting method further comprises: dehydrating the iron-based minerals and flux, respectively, to a water content of less than 1wt%; and grinding the dehydrated iron-based minerals and flux to a particle size of less than 150μm.

[0028] The suspension side-blown electric heat smelting furnace provided by the present application effectively solves the problems of energy quality imbalance, high iron content in slag, and low reaction efficiency in the current flash furnace smelting process by organically combining the suspension smelting technology, the side-blown bath smelting technology, and the electric heat temperature-raising settling technology. BRIEF DESCRIPTION OF DRAWINGS

[0029] The accompanying drawings, which form a part of the present application, are intended to provide further understanding of the present application, and are used to interpret the illustrative embodiments of the present application and their descriptions, and do not constitute improper limitations to the present application. In the drawings:

[0030] Figure 1 Fig. 1 shows a structure schematic diagram of a suspension side-blown electric heat smelting furnace according to an embodiment of the present application.

[0031] In the above drawings, the following reference signs are used:

[0032] 10, suspension reaction tower; 101, smelting material spraying inlet; 102, first spraying gun; 11, preheating zone; 12, reduction zone; 13, melting zone; 20, settling tank; 21, side-blown zone; 22, electric heat zone; 201, second spraying gun; 202, heating electrode; 203, heat supplement burner; 204, smoke outlet; 205, metal discharge outlet; 206, upper slag outlet; 207, lower slag outlet; 30, upward flue. DETAILED DESCRIPTION

[0033] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0034] As described in the background section, the current flash furnace smelting process has the problems of insufficient smelting, high valuable metal content in slag, and resource waste. In order to solve the above problems, the present application provides a suspension side-blown electric heat smelting furnace, as shown in Figure 1As shown, the smelting furnace comprises a suspension reaction tower 10 and a settling tank 20 arranged integrally, and further comprises a reducing agent supply unit, a fuel supply unit and an oxygen-containing gas supply unit; wherein: the top of the suspension reaction tower 10 is provided with a smelting ore material injection port 101, and the top and / or side thereof is further provided with a plurality of first injection guns 102, each of which is independently connected to at least one of the reducing agent supply unit, the fuel supply unit or the oxygen-containing gas supply unit, and the suspension reaction tower 10 is used for smelting reaction of the smelting ore material in a suspension state; the settling tank 20 has a horizontal structure, and along the length direction of the settling tank 20, the settling tank 20 comprises a side-blown area 21 and an electric heating area 22 connected in series, and the top of the side-blown area 21 is directly connected to the bottom of the suspension reaction tower 10; a plurality of second injection guns 201 are arranged on the side wall of the side-blown area 21, and the electric heating area 22 is provided with heating electrodes 202; each of the second injection guns 201 is independently connected to at least one of the reducing agent supply unit, the fuel supply unit and the oxygen-containing gas.

[0035] In actual operation, the smelting ore material can be injected into the suspension reaction tower 10 in a dispersed state through the smelting ore material injection port 101, and the top and / or side of the suspension reaction tower 10 is further provided with a plurality of first injection guns 102, which can inject reducing agent, fuel and oxygen-containing gas into different areas to realize temperature and atmosphere control of the material in different areas, thereby realizing suspension smelting reaction in the suspension reaction tower 10, preliminary reduction of the metal in the ore material and melting of the material. The smelting melt produced in the suspension reaction tower 10 directly falls into the side-blown area 21, and since the second injection guns 201 are arranged in this area, one or more of reducing agent, fuel and oxygen-containing gas can be further injected into the slag layer of the molten pool to utilize the excellent metallurgical dynamic conditions of the molten pool smelting to efficiently reduce the valuable metals in the slag layer while supplementing heat. The good metallurgical dynamic conditions also effectively alleviate the deposition of high-melting-point substances to form a furnace bond, thereby protecting the volume of the settling tank and further protecting the enrichment and settlement of the valuable metals, and the on-site operation pressure is small, which is easier to implement. The smelting products produced in the side-blown area 21 further enter the electric heating area 22, and the heating electrodes can further provide the heat required for reaction and temperature increase. Moreover, the electric heating area molten pool is easy to supplement heat, relatively calm and weakly stirred, which can further efficiently settle the valuable metals physically lost in the slag layer, and further reduce the valuable metals in the slag to realize deep recovery.

[0036] Therefore, the suspension side-blown electric heating smelting furnace combines the suspension smelting technology, the side-blown molten pool smelting technology and the electric heating temperature increase and settlement technology, and effectively solves the problems of energy and quality imbalance, high iron content in slag and low reaction efficiency in the current flash smelting process. The suspension side-blown electric heating smelting furnace can not only process sulfide ore materials, but also process oxide ore materials.

[0037] In a preferred embodiment, the suspension reaction tower 10 is divided into a preheating zone 11, a reduction zone 12, and a melting zone 13 from top to bottom. The plurality of first spray guns 102 include at least three groups, with each group comprising at least two first spray guns 102. At least one group of first spray guns 102 is provided in each of the preheating zone 11, reduction zone 12, and melting zone 13. Thus, after the ore to be smelted enters the suspension reaction tower 10 in a dispersed state, it is first preheated in the preheating zone 11, then initially reduced in the reduction zone 12, and finally melted in the melting zone 13 to form a melt. In specific implementation, the injected material of the first spray gun 102 can be adjusted according to the function of different areas. Preferably, the first spray gun 102 located in the preheating zone 11 is connected to the fuel supply unit and the oxygen-containing gas supply unit; wherein, the first spray gun 102 located in the preheating zone 11 is a dual-channel spray gun, with its inner channel connected to the oxygen-containing gas supply unit and its outer channel connected to the fuel supply unit; or, the first spray gun 102 located in the preheating zone 11 is a single-channel spray gun, with one part connected to the oxygen-containing gas supply unit and the other part connected to the fuel supply unit; thus, the preheating function is achieved; in the reduction zone 12, a part of the first spray gun 102 is a single-channel spray gun connected to the reducing agent supply unit, and the other part is a dual-channel spray gun, with its inner channel connected to the oxygen-containing gas supply unit and its outer channel connected to the fuel supply unit; or... The first spray gun 102 in the reduction zone 12 is a three-channel spray gun, with its inner channel connected to the reducing agent supply unit, the middle channel connected to the oxygen-containing gas supply unit, and the outer channel connected to either the reducing agent supply unit or the fuel supply unit. This achieves preliminary reduction of the preheated material and provides supplementary heating for the preliminary reduction process, resulting in more complete reduction. In the melting zone 13, part of the first spray gun 102 is a single-channel spray gun connected to the reducing agent supply unit, while another part is a dual-channel spray gun, with its inner channel connected to the oxygen-containing gas supply unit and its outer channel connected to the fuel supply unit. Alternatively, the first spray gun 102 in the melting zone 13 can be a three-channel spray gun, with its inner channel connected to the reducing agent supply unit, the middle channel connected to the oxygen-containing gas supply unit, and the outer channel connected to either the reducing agent supply unit or the fuel supply unit. This melts the pre-reduced material and further deepens the reduction process, thus better promoting the reduction and recovery of valuable metals.

[0038] Preferably, such as Figure 1 As shown, the suspended side-blown electric heating smelting furnace also includes an ascending flue 30, which is located at the top of and connected to the side-blown zone 21. The ascending flue 30 is located at the end of the side-blown zone 21 closer to the electric heating zone 22, while the suspended reaction tower 10 is located at the end of the side-blown zone 21 farther from the electric heating zone 22. In this way, the molten metal can fall into the side-blown zone 21 from the end away from the electric heating zone 22, and the flue gas can be discharged from the other end, which is more conducive to the full smelting of the molten pool.

[0039] More preferably, the updraft flue 30 is also integrally arranged with the settling tank 20, and the side wall of the updraft flue 30 near the electric heating zone 22 extends into the settling tank 20 to form a partition wall between the side-blown zone 21 and the electric heating zone 22. A communication passage is arranged between the partition wall and the bottom wall of the settling tank to facilitate the flow of smelting products into the electric heating zone 22.

[0040] In a preferred embodiment, the second lances 201 are each independently connected to at least one of the reducing agent supply unit, the fuel supply unit, and the oxygen-containing gas supply unit. One or more of the reducing agent, the fuel, and the oxygen-containing gas can be selectively injected through the second lances 201 to provide the kinetic conditions and the required atmosphere for the smelting of the molten bath. In a specific lance arrangement, the second lances 201 are three-channel integrated lances, the inner channel of which is connected to the reducing agent supply unit, the middle channel is connected to the oxygen-containing gas supply unit, and the outer channel is connected to the reducing agent supply unit or the fuel supply unit; alternatively, some of the second lances 201 are single-channel lances connected to the reducing agent supply unit, and the others are double-channel lances, the inner channel of which is connected to the oxygen-containing gas supply unit, and the outer channel is connected to the reducing agent supply unit or the fuel supply unit.

[0041] In order to further supplement heat to the smelting reaction process of the molten bath, a plurality of heat supplement burners 203 are arranged at the top of the side-blown zone 21. Such an arrangement facilitates the more complete reduction and recovery of valuable metals, while reducing the viscosity of the slag layer, making it easier for the metals to settle and separate.

[0042] In order to further balance the time length of the smelting and electric heating settling, and to promote the settling and separation of the metal and slag layers on the basis of ensuring efficient reduction of the smelting, in a preferred embodiment, the ratio of the length of the side-blown zone 21 to the length of the electric heating zone 22 along the length direction of the settling tank 20 is 0.5-3:1. In addition, preferably, the bottom wall of the side-blown zone 21 is flush with the bottom wall of the electric heating zone 22, or the bottom wall of the electric heating zone 22 is lower than the bottom wall of the side-blown zone 21; the top height of the side-blown zone 21 is higher than the top height of the electric heating zone 22. The higher top of the side-blown zone 21 is to accommodate the higher splashes in this section. The lower top of the electric heating zone 22 can improve the efficiency of heat energy utilization and reduce construction investment. In actual arrangement, the bottom wall of the electric heating zone 22 is preferably lower than the bottom wall of the side-blown zone 21 to facilitate the flow of the melt, and the height difference is preferably controlled within the range of 100-500 mm. The connecting structure between the two zones includes but is not limited to a step structure or a slope structure.

[0043] In a preferred embodiment, the top of the electric heating zone 22 is further provided with a reducing agent feeding port or a third lance connected with a reducing agent supply unit; the top of the electric heating zone 22 is further provided with a smoke outlet 204, the bottom is further provided with a metal discharge port 205, the side is further provided with an upper slag outlet 206 and a lower slag outlet 207 (the height of the upper slag outlet 206 is higher than that of the lower slag outlet 207). In this way, the reducing agent can be further added in the electric heating zone to further promote the electric heating reduction of the slag layer, and finally the metal layer and the slag layer are formed, the metal layer can be discharged through the metal discharge port 205, and the slag can be discharged through the upper slag outlet 206 or the lower slag outlet 207, and in actual operation, the upper and lower slag outlets can be selected according to the liquid level in the furnace.

[0044] The above-mentioned suspension side-blown electric heating smelting furnace provided by the present application can be applied to the smelting of oxide and sulfide minerals, such as the smelting of various metal ore materials of iron, copper, nickel, lead, solid waste, etc.

[0045] According to another aspect of the present application, a smelting method of iron-based minerals is also provided, which smelts the iron-based minerals by using the above-mentioned suspension side-blown electric heating smelting furnace, and the smelting method comprises the following steps: iron-based minerals and flux are sprayed into the top of the suspension reaction tower 10 through the ore material spraying port 101 by taking compressed air or inert gas as the carrier, and at least one of reducing agent, fuel or oxygen-containing gas is sprayed into the suspension reaction tower 10 through the first lance 102 to make the iron-based minerals perform a suspension smelting reaction; the smelting melt obtained by the suspension smelting reaction directly falls into the side-blown zone 21 of the settling tank 20 through the bottom of the suspension reaction tower 10, and at least one of reducing agent, fuel or oxygen-containing gas is further sprayed into the slag layer of the side-blown zone 21 through the second lance 201 to make the smelting melt perform a bath smelting reaction; the smelting product obtained by the bath smelting reaction enters the electric heating zone 22 of the settling tank 20, and performs electric heating reduction under the heating of the heating electrode 202 to obtain molten iron and slag.

[0046] As described above, in actual operation, compressed air or inert gas (such as nitrogen) can spray the iron-based minerals and fluxes into the suspension reaction tower 10 through the material injection port 101 and present a dispersed state. The top and / or side of the suspension reaction tower 10 is also provided with a plurality of first lances 102, which can spray the reducing agent, fuel and oxygen-containing gas into different areas to control the temperature and atmosphere of the material in different areas, so as to realize the suspension smelting reaction in the suspension reaction tower 10, and realize the preliminary reduction of iron and other valuable metals in the material and the melting of the material. In the first stage of the suspension smelting process, the reduction rate of iron can reach more than 45%. The smelting melt produced in the suspension reaction tower 10 directly falls into the side-blown area 21, and since the second lance 201 is arranged in this area, one or more of the reducing agent, fuel and oxygen-containing gas can be further sprayed into the slag layer of the molten pool to efficiently reduce the valuable metals in the slag layer by taking advantage of the excellent metallurgical dynamic conditions of the molten pool smelting while supplementing heat. The good metallurgical dynamic conditions also effectively alleviate the deposition of high-melting-point substances to form a furnace clinker, protect the sedimentation tank volume, and further protect the enrichment and sedimentation of valuable metals, and the on-site operation pressure is small, which is easier to implement. By using the side-blown molten pool smelting, the reduction rate of iron can reach more than 90%. The smelting product produced in the side-blown area 21 further enters the electric heating area 22, and the heating electrode can further provide the heat required for the reaction and temperature rise. And by taking advantage of the easy, relatively calm and weak stirring characteristics of the electric heating area molten pool, the valuable metals lost in the slag layer can be further efficiently settled, and the valuable metals in the slag can be further reduced to achieve their deep recovery, the reduction rate of iron can reach more than 99%, and finally the molten iron and the slag with very low valuable metal content are obtained.

[0047] The suspension side-blown electric heating smelting furnace combines the suspension smelting technology, the side-blown molten pool smelting technology and the electric heating temperature-raising and sedimentation technology organically, and directly uses the powdery material. The reduction process has the chemical kinetic advantages of large gas-solid contact area, rapid mass and heat transfer, and fast reaction speed. The reaction speed is fast and the thermal intensity is high in the molten pool smelting process, and the kinetic conditions are good. The valuable metals can be deeply recovered in the electric heating area, and the economy is good. Therefore, the iron-based minerals can be efficiently, short-process, low-cost and environmentally friendly smelted, the metal and the slag are fully separated, and the problems of insufficient smelting, too high valuable metal content in the slag and resource waste in the current flash smelting process are effectively solved.

[0048] In a preferred embodiment, the suspension reaction tower 10 is divided into a preheating zone 11, a reduction zone 12 and a melting zone 13 from top to bottom, and during the suspension smelting reaction process, the temperature of the preheating zone 11 is controlled to be 600-1000°C, the temperature of the reduction zone 12 is controlled to be 1000-1450°C, and the temperature of the melting zone 13 is controlled to be 1450-1650°C. During the falling process of the iron-based minerals and fluxes in the hearth of the suspension reaction tower 10, they pass through the three zones, i.e. the preheating zone, the reduction zone and the melting zone, and are heated by the high-temperature reducing gas and rapidly reduced in a few seconds of falling time, and then drop into the molten pool. Controlling the temperature of each zone within the above range is beneficial to fully complete the preliminary reduction and melting, and also has a better promoting effect on the iron reduction separation of the entire iron-based minerals.

[0049] Preferably, the fuel and the oxygen-containing gas are injected into the preheating zone 11 through the first lance 102 arranged in the preheating zone 11 to control the temperature of the preheating zone 11; the fuel, the oxygen-containing gas and the reducing agent are injected into the reduction zone 12 through the first lance 102 arranged in the reduction zone 12 to control the temperature of the reduction zone 12 and make the iron-based minerals perform the preliminary suspension smelting reaction; and the fuel, the oxygen-containing gas and the reducing agent are injected into the melting zone 13 through the first lance 102 arranged in the melting zone 13 to control the temperature of the melting zone 13, make the iron-based minerals perform the further suspension smelting reaction, and make the obtained smelting product melt to form a smelting melt. In this way, the fuel injected into the preheating zone can promote the rapid preheating of the iron-based minerals and fluxes, and then the subsequent entering into the reduction zone can perform the preliminary reduction under the fuel supplement heating effect of the reducing agent, and finally after the further deep reduction and melting of the melt into the melt, it directly falls into the settling tank. Specifically, the first lance 102 arranged in the preheating zone 11 can be arranged at the top and / or side of the suspension reaction tower 10, and the first lances 102 of the other two zones can be arranged at the side of the suspension reaction tower 10.

[0050] In order to make the molten pool smelting process more efficient and further improve the iron reduction rate, in a preferred embodiment, the temperature of the side-blown zone 21 is controlled to be 1550-1650°C during the molten pool smelting reaction process;

[0051] Preferably, the second lance 201 is a three-channel integrated lance, through the inner channel of which a reducing agent is sprayed into the slag layer of the side-blown zone 21, through the middle channel of which an oxygen-containing gas is sprayed into the slag layer of the side-blown zone 21, and through the outer channel of which a reducing agent or fuel is sprayed into the slag layer of the side-blown zone 21; or, among the plurality of second lances 201, part of them are single-channel lances for spraying a reducing agent into the slag layer of the side-blown zone 21, and the other part of them are double-channel lances, through the inner channel of which an oxygen-containing gas is sprayed into the slag layer of the side-blown zone 21, and through the outer channel of which a reducing agent or fuel is sprayed into the slag layer of the side-blown zone 21. Preferably, the side-blown zone 21 is heated by the heat-supply burner 203 to maintain the temperature of the side-blown zone 21. The second lances are arranged in the slag layer so that the combustion and reduction occur in the molten slag, which improves the heat utilization rate and can cause the stirring heat transfer rate of the molten bath to increase, and also can achieve the reduction of most of the iron and heat supply for the endothermic reduction, without causing the molten iron at the bottom to be re-rolled into the slag. Preferably, during the smelting reaction of the molten bath, coke is added to the molten bath so that the material is carburized during the penetration process. The coke is added on one hand to further reduce the iron oxides, and on the other hand to serve as a carburizing agent so that the molten iron reduced by the suspension tower passes through the coke layer, the carbon content of the molten iron is increased, and the melting point is lowered, which is beneficial to the subsequent operation and composition requirements. In the specific adding process, the coke can be added through the ore injection inlet 101 above the suspension reaction tower, or can also be injected from the side-blown zone 21 of the settling tank 20. The amount of coke added can be adjusted according to the carbon content of the molten iron, and is preferably about 4%.

[0052] In a preferred embodiment, during the electrothermal reduction, the temperature of the electrothermal zone 22 is controlled to be 1550-1780°C; preferably, during the electrothermal reduction, blocky reducing agents are added to the electrothermal zone 22 through the reducing agent feeding port at the top of the electrothermal zone 22, or reducing agents are sprayed into the electrothermal zone 22 through the third lance. The electrothermal settling is carried out at the above-mentioned temperature, which has a better settling efficiency, and further adding of reducing agents can deepen the electrothermal reduction, thereby improving the reduction rate of iron. In the specific implementation process, the blocky reducing agents are added to the slag layer through the reducing agent feeding port, or the reducing agents are sprayed into the slag layer through the third lance with inert gas as the carrier, which can send the reducing agents into the slag layer to achieve the deep reduction of the valuable metal oxides such as iron in the slag and the static settling of the inclusions in the slag, and obtain the molten iron.

[0053] Preferably, the lump reducing agent is one or more of lump coal, coke, petroleum coke, silicon-manganese, silicon-iron, manganese-iron; the injected reducing agent is one or more of powdered reducing agent and / or gaseous reducing agent, preferably one or more of powdered coal, coke powder, petroleum coke powder, graphite powder, natural gas, coal gas, coal gas, hydrogen; the fuel is one or more of natural gas, heavy oil, coal powder, coal gas, coal gas, hydrogen, coke powder, gasoline; the oxygen-containing gas is oxygen-enriched air (oxygen concentration of 40-100%) or oxygen; the iron-based mineral is one or more of iron concentrate, vanadium-titanium magnetite, sea sand ore, high-phosphorus iron ore, laterite nickel ore (with iron ore), and iron-containing solid waste, preferably one or more of red mud, copper smelting slag, copper lean slag; the flux is a calcareous flux, preferably quicklime and / or limestone.

[0054] If the above materials are gaseous, they can be directly injected through the corresponding lance; if the above materials are powdered solid, the specific injection form not mentioned above can be injected through the injection of inert gas such as nitrogen, argon, etc. as a carrier gas. This is understood by those skilled in the art, and will not be described here.

[0055] In a preferred embodiment, the batching process is according to the following principle: the iron-based mineral and the flux are batched according to a binary basicity CaO / SiO2=0.5-1.5, i.e. the weight of CaO in the flux / the SiO2 content in the mineral material=0.5-1.5. According to the above batching method, it is more conducive to the separation of metal and slag, and the melting point of the material is relatively low, thus being conducive to energy saving and improving the reduction effect.

[0056] In actual smelting process, in order to further improve the smelting efficiency in the suspension reaction tower, in a preferred embodiment, before the iron-based mineral and the flux are injected through the smelting mineral material injection port 101, the smelting method further comprises: the iron-based mineral and the flux are both subjected to dehydration treatment, and the water content is less than 1wt%; the dehydrated iron-based mineral and the flux are both subjected to fine grinding, and the particle size is less than 150μm.

[0057] The flue gas produced in the smelting process usually has a temperature of 1400-1700℃, which can be sequentially subjected to secondary combustion to remove entrained CO, H2, etc. combustible gas, waste heat boiler to recover waste heat for power generation, purification treatment (dust removal, desulfurization), etc., i.e. up to standard emission, and the collected flue dust can be returned to the batching stage.

[0058] In summary, the iron-based mineral treated by the method provided by the present application has the following beneficial effects:

[0059] 1. The process can be widely applied to iron concentrate, vanadium-titanium magnetite, sea sand ore, high-phosphorus iron ore, laterite nickel ore, etc., and can also be applied to iron-containing solid waste such as red mud, copper smelting slag, copper lean slag, etc., and has strong adaptability to raw materials; the technology does not need a sintering process with a balling machine, shortens the process flow, and has a high recovery rate of valuable elements.

[0060] 2. This invention is a new, efficient, short-process ironmaking technology that integrates suspension smelting, molten pool smelting, and electrothermal reduction technologies. The first stage is the suspension smelting zone, which features good kinetic conditions and fast reduction speed; the second stage is the side-blown molten pool smelting reduction zone, which has high thermal efficiency, strong agitation capacity, and fast reaction speed; the third stage is the electrothermal reduction zone, which can deeply reduce residual valuable elements and complete the settling of metals in the slag, thereby improving the metal recovery rate.

[0061] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0062] Example 1:

[0063] This embodiment adopts Figure 1 The process for treating iron-based minerals (high-phosphate ore, whose composition and content are shown in the table below) using a suspended side-blown electric heating furnace is as follows:

[0064] Table 1

[0065] Component TFe P CaO SiO2 MgO wt% 46.65 0.81 5.52 10.02 0.76 Component Al2O3 Fe2O3 P2O5 wt% 5.97 64.34 1.90

[0066] Using the aforementioned high-phosphate ore as raw material and quicklime as flux, both materials are dehydrated to 0.5% and ground to a particle size of 75 micrometers. The flux ratio is adjusted according to the binary basicity (CaO content in flux / SiO2 content in material), with the binary basicity CaO / SiO2 = 0.8. The raw materials are premixed according to the binary basicity scheme and then injected into the suspension reactor tower via nozzles using compressed air, resulting in a dispersed distribution. Within the suspension reactor tower, the materials pass through a preheating zone, a reduction zone, and a melting zone, at temperatures of 800℃, 1300℃, and 1550℃, respectively. In the preheating zone, oxygen-enriched air (70% oxygen concentration) and natural gas are injected through the lances. In the reduction and melting zones, oxygen-enriched air (70% oxygen concentration), natural gas, and pulverized coal are injected. The smelting melt exiting the suspension reactor tower (with a reduction rate of 60% for iron oxides to metal) falls in liquid form into the side-blown zone for side-blown smelting. The temperature in this zone is controlled at 1580℃. An integrated spray gun is used: the spray gun sprays oxygen-rich (80% oxygen concentration), fuel (coal powder), and reducing agent (coal powder) to achieve 95% reduction of metal oxides in iron-containing materials. The slag and molten iron produced in the side-blowing zone enter the electrothermal reduction section. The reducing agent can be added by feeding the reducing agent (lump coal) from the top of the furnace. Ultimately, the deep reduction of valuable metal oxides such as iron in the slag and the static sedimentation of metal inclusions in the slag are achieved to obtain molten iron. The operating temperature of the electrothermal reduction section is 1600℃, the iron reduction rate is 98.5%, the recovery rate is 97%, the flue gas temperature is 1580℃, and the molten iron and slag are discharged periodically.

[0067] Example 2:

[0068] This example uses Figure 1 An iron-based mineral (vanadium-titanium magnetite, whose components and contents are shown in the following table) was treated by a suspension side-blown electrothermal smelting furnace as shown in

[0069] Table 2

[0070] Component TFe [V2O5] TiO2 CaO SiO2 MgO wt% 55.08 1.74 13.78 0.07 1.46 1.00 Component Al2O3 Fe2O3 [P2O5] FeO wt% 3.83 69.6 0.3 8.24

[0071] Vanadium-titanium magnetite was used as raw material, and limestone was used as flux. Both were dehydrated to 0.4% and ground to 95 microns. The flux ratio was adjusted according to the binary basicity (CaO content in the flux / SiO2 content in the material), and the binary basicity CaO / SiO2 was adjusted to 0.8. The raw materials were premixed according to the binary basicity scheme and then sprayed into the suspension reaction tower through the nozzle, and were dispersedly distributed. They passed through the preheating zone, the reduction zone, and the melting zone in the suspension reaction tower, and the temperatures were 900°C, 1350°C, and 1500°C, respectively. Oxygen-rich (80% oxygen concentration) and coal powder were sprayed in the preheating zone, and oxygen-rich (70% oxygen concentration), coal powder, and hydrogen were sprayed in the reduction zone and the melting zone. The smelting melt (the reduction rate of iron oxides to metal was controlled at 50%) from the suspension reaction tower fell into the side-blown zone in a liquid form for side-blown bath smelting. The temperature in this zone was controlled at 1550°C, and the spray gun was a split type spray gun. One spray gun sprayed coal powder with nitrogen as the carrier gas, and the other spray gun was a double-channel spray gun that sprayed oxygen-rich (oxygen concentration 60%) and natural gas to achieve 95% reduction of metal oxides in the iron-containing material. The slag and molten iron generated in the side-blown zone entered the electrothermal reduction section, and the reduction agent was added in the form of top charging. Finally, deep reduction of iron and other valuable metal oxides in the slag and static settling of the inclusions in the slag were achieved, and molten iron was obtained. The operating temperature in the electrothermal reduction section was 1650°C, the reduction rate of iron was 99%, the recovery rate was 95.5%, the flue gas temperature was 1600°C, and the molten iron and slag were discharged regularly.

[0072] Example 3:

[0073] This example uses Figure 1 An iron-based mineral (vanadium-titanium magnetite, whose components and contents are shown in the following table) was treated by a suspension side-blown electrothermal smelting furnace as shown in

[0074] Table 3

[0075] Component TFe FeO MgO CaO SiO2 Al2O3 wt% 65.27 18.36 0.17 0.06 4.86 0.39

[0076] Iron ore concentrate as raw material, lime as flux, dehydrated to 0.2%, particle size ground to 100 microns; the flux ratio according to the binary basicity (CaO content in the flux / SiO2 content in the material), adjust the binary basicity CaO / SiO2=1.0. The raw material into the furnace is pre-mixed according to the binary basicity scheme and sprayed into the suspension reaction tower through the nozzle, which is dispersedly distributed. In the suspension reaction tower, it passes through the preheating zone, the reduction zone and the melting zone respectively, the temperatures are 700℃, 1350℃ and 1600℃ respectively, the preheating area sprays oxygen-rich (80% concentration oxygen) and coal gas, the reduction zone and the melting zone spray oxygen-rich (80% concentration oxygen), hydrogen and coal powder. The smelting melt (the reduction rate of iron oxide to metal is controlled at 70%) from the suspension reaction tower falls to the side-blown area in liquid form for side-blown bath smelting. The temperature in this area is controlled at 1650℃, and the integrated lance is selected for the lance: the lance sprays oxygen-rich (oxygen concentration 80%), fuel (natural gas) and reducing agent (hydrogen), achieving 93% reduction of metal oxides in the iron-containing material; the slag and molten iron produced in the side-blown area enter the electric heating reduction section, and the reducing agent is added by adding block coal at the top of the furnace, finally realizing deep reduction of iron and other valuable metal oxides in the slag and static settling of inclusions in the slag, obtaining molten iron; the operating temperature of the electric heating reduction section is 1650℃, the reduction rate of iron is 99%, the recovery rate is 97%, the flue gas temperature is 1600℃, and the molten iron and slag are discharged regularly.

[0077] Example 4:

[0078] This example uses Figure 1 The suspension side-blown electric smelting furnace shown in the figure processes iron-based minerals (red mud, its components and contents are shown in the table below), and the specific process is as follows:

[0079] Table 4

[0080] Component TFe Na2O TiO2 CaO SiO2 MgO wt% 46.77 1.02 5.35 0.19 1.93 0.14 Component Al2O3 S P FeO K2O wt% 12.45 0.03 0.06 0.38 0.05

[0081] The red mud is used as raw material, and the limestone is used as flux. Both are dehydrated to 0.2%, and the particle size is ground to 65 microns. The flux is mixed according to the binary basicity (CaO content in the flux / SiO2 content in the material), and the binary basicity CaO / SiO2 is adjusted to 0.8. The raw material is pre-mixed according to the binary basicity scheme, and then sprayed into the suspension reaction tower through the nozzle, and is dispersedly distributed. In the suspension reaction tower, it passes through the preheating zone, the reduction zone and the melting zone, respectively, and the temperatures are 900℃, 1350℃ and 1500℃, respectively. In the preheating zone, the oxygen-rich (80% concentration of oxygen) and the coal gas are sprayed by the spray gun. In the reduction zone and the melting zone, the oxygen-rich (70% concentration of oxygen), the heavy oil and the coal powder are sprayed. The smelting melt (the reduction rate of the reduction of the iron oxide into the metal is controlled to 80%) from the suspension reaction tower falls into the side-blown zone in a liquid form to carry out the side-blown bath smelting. The temperature in the zone is controlled to 1550℃, and the split-type spray gun is selected: one spray gun sprays the hydrogen gas; and one spray gun is a double-channel spray gun, which sprays the oxygen-rich (60% concentration of oxygen) and the natural gas, so that the 95% reduction of the metal oxide in the iron-containing material is realized. The slag and the molten iron generated in the side-blown zone enter the electric heating reduction section, and the reduction agent is added in the form of the block coal added from the top of the furnace, so that the deep reduction of the iron oxide and the static settlement of the inclusion metal in the slag are finally realized, and the molten iron is obtained. The operating temperature of the electric heating reduction section is 1650℃, the reduction rate of the iron is 99%, the recovery rate is 94%, the flue gas temperature is 1600℃, and the molten iron and the slag are discharged regularly.

[0082] Comparative Example 1

[0083] On the basis of Example 1, the side-blown spray gun in the side-blown zone is cancelled, and the others remain the same as in Example 1. The final reduction rate of the iron is 80%, and the recovery rate is 78%.

[0084] Comparative Example 2

[0085] On the basis of Example 1, the heating electrode of the electric heating zone and the reduction agent added in the electric heating zone are cancelled, and only the settlement treatment is carried out. The final reduction rate of the iron is 93%, and the recovery rate is 90%.

[0086] The above only describes the preferred embodiments of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A suspended side-blown electric heating smelting furnace, characterized in that, The system includes an integrated suspension reaction tower (10) and sedimentation tank (20), as well as a reducing agent supply unit, a fuel supply unit, and an oxygen-containing gas supply unit; wherein: The suspension reaction tower (10) has a ore injection inlet (101) at the top and a plurality of first spray guns (102) on the top and / or sides. Each of the first spray guns (102) is independently connected to at least one of the reducing agent supply unit, the fuel supply unit, or the oxygen-containing gas supply unit. The suspension reaction tower (10) is used to carry out a suspension smelting reaction on the ore to be smelted. The suspension reaction tower (10) is divided into a preheating zone (11), a reduction zone (12), and a melting zone (13) from top to bottom. The plurality of first spray guns (102) includes at least three groups. Each group of first spray guns (102) includes at least two first spray guns (102). The preheating zone (11), the reduction zone (12), and the melting zone (13) are each provided with at least one group of first spray guns (102). A portion of the first spray guns (102) provided in the reduction zone (12) are single-channel spray guns and are connected to the reducing agent supply unit. Another part is a dual-channel spray gun, with its inner channel connected to the oxygen-containing gas supply unit and its outer channel connected to the fuel supply unit; or, the first spray gun (102) set in the reduction zone (12) is a three-channel spray gun, with its inner channel connected to the reducing agent supply unit, its middle channel connected to the oxygen-containing gas supply unit, and its outer channel connected to the reducing agent supply unit or the fuel supply unit; a part of the first spray gun (102) set in the melting zone (13) is a single-channel spray gun and connected to the reducing agent supply unit, and another part is a dual-channel spray gun, with its inner channel connected to the oxygen-containing gas supply unit and its outer channel connected to the fuel supply unit; or, the first spray gun (102) set in the melting zone (13) is a three-channel spray gun, with its inner channel connected to the reducing agent supply unit, its middle channel connected to the oxygen-containing gas supply unit, and its outer channel connected to the reducing agent supply unit or the fuel supply unit; The sedimentation tank (20) has a horizontal structure. Along the length of the sedimentation tank (20), the sedimentation tank (20) includes a connected side blowing zone (21) and an electric heating zone (22). The top of the side blowing zone (21) is directly connected to the bottom of the suspension reaction tower (10). A plurality of second spray guns (201) are provided on the side wall of the side blowing zone (21), and heating electrodes (202) are provided in the electric heating zone (22). Each of the second spray guns (201) is independently connected to at least one of the reducing agent supply unit, the fuel supply unit, and the oxygen-containing gas.

2. The suspended side-blown electric heating smelting furnace according to claim 1, characterized in that, The first spray gun (102) disposed in the preheating zone (11) is connected to the fuel supply unit and the oxygen-containing gas supply unit; wherein, the first spray gun (102) disposed in the preheating zone (11) is a dual-channel spray gun, the inner channel of which is connected to the oxygen-containing gas supply unit and the outer channel of which is connected to the fuel supply unit; or, the first spray gun (102) disposed in the preheating zone (11) is a single-channel spray gun, one part of which is connected to the oxygen-containing gas supply unit and the other part of which is connected to the fuel supply unit.

3. The suspended side-blown electrothermal smelting furnace according to claim 1 or 2, characterized in that, The suspended side-blown electric heating smelting furnace also includes an ascending flue (30), which is located at the top of the side-blown zone (21) and connected thereto. The ascending flue (30) is located at one end of the side-blown zone (21) near the electric heating zone (22), and the suspended reaction tower (10) is located at one end of the side-blown zone (21) away from the electric heating zone (22).

4. The suspended side-blown electrothermal smelting furnace according to claim 3, characterized in that, The rising flue (30) and the sedimentation tank (20) are also integrated, and the side wall of the rising flue (30) near the electric heating zone (22) extends into the sedimentation tank (20) to form a partition wall between the side blowing zone (21) and the electric heating zone (22).

5. The suspension side-blown electric heating smelting furnace according to claim 1 or 2, characterized in that, Each of the second spray guns (201) is independently connected to at least one of the reducing agent supply unit, the fuel supply unit and the oxygen-containing gas supply unit.

6. The suspension side-blown electric heating smelting furnace according to claim 5, characterized in that, The second spray gun (201) is a three-channel integrated spray gun, with its inner channel connected to the reducing agent supply unit, its middle channel connected to the oxygen-containing gas supply unit, and its outer channel connected to either the reducing agent supply unit or the fuel supply unit; or, Of the multiple second spray guns (201), some are single-channel spray guns connected to the reducing agent supply unit, and others are dual-channel spray guns, with the inner channel connected to the oxygen-containing gas supply unit and the outer channel connected to the reducing agent supply unit or the fuel supply unit.

7. The suspended side-blown electric heating smelting furnace according to claim 5, characterized in that, The top of the side-blowing zone (21) is also provided with multiple heat-replenishing burners (203).

8. The suspended side-blown electrothermal smelting furnace according to claim 1 or 2, characterized in that, Along the length of the sedimentation tank (20), the ratio of the length of the side blowing zone (21) to the length of the electric heating zone (22) is 0.5 to 3:

1.

9. The suspended side-blown electric heating smelting furnace according to claim 8, characterized in that, The side-blowing area (21) is flush with the bottom wall of the electric heating area (22), or the bottom wall of the electric heating area (22) is lower than the bottom wall of the side-blowing area (21); the top height of the side-blowing area (21) is higher than the top height of the electric heating area (22).

10. A method for smelting iron-based minerals, characterized in that, The iron-based mineral is smelted using a suspension side-blown electric heating furnace as described in any one of claims 1 to 9, the smelting method comprising the following steps: Using compressed air or inert gas as a carrier, iron-based minerals and flux are injected from the top of the suspension reaction tower (10) through the ore injection port (101). At the same time, at least one of a reducing agent, fuel or oxygen-containing gas is injected into the suspension reaction tower (10) through the first spray gun (102) so that the iron-based minerals undergo a suspension smelting reaction. The smelting melt obtained by the suspension smelting reaction falls directly from the bottom of the suspension reaction tower (10) into the side blowing zone (21) of the settling tank (20). At least one of the reducing agent, the fuel or the oxygen-containing gas is further sprayed into the slag layer of the side blowing zone (21) through the second spray gun (201) so that the smelting melt undergoes a molten pool smelting reaction. The smelting products obtained from the molten pool smelting reaction enter the electrothermal zone (22) of the sedimentation tank (20) and undergo electrothermal reduction under the heating of the heating electrode (202) to obtain molten iron and slag.

11. The smelting method for iron-based minerals according to claim 10, characterized in that, The suspension reaction tower (10) is divided into a preheating zone (11), a reduction zone (12) and a melting zone (13) from top to bottom. During the suspension smelting reaction, the temperature of the preheating zone (11) is controlled at 600~1000℃, the temperature of the reduction zone (12) is controlled at 1000~1450℃, and the temperature of the melting zone (13) is controlled at 1450~1650℃.

12. The smelting method for iron-based minerals according to claim 11, characterized in that, The temperature of the preheating zone (11) is controlled by spraying the fuel and the oxygen-containing gas into the preheating zone (11) through the first spray gun (102) located therein; the temperature of the reduction zone (12) is controlled by spraying the fuel, the oxygen-containing gas and the reducing agent into the reduction zone (12) through the first spray gun (102) located therein, and the iron-based mineral undergoes the initial suspension smelting reaction; the temperature of the melting zone (13) is controlled by spraying the fuel, the oxygen-containing gas and the reducing agent into the melting zone (13) through the first spray gun (102) located therein, and the iron-based mineral undergoes the further suspension smelting reaction, and the resulting smelting product is melted to form the smelting melt.

13. The method for smelting iron-based minerals according to any one of claims 10 to 12, characterized in that, During the molten pool smelting reaction, the temperature of the side-blowing zone (21) is controlled at 1550~1650℃.

14. The smelting method for iron-based minerals according to claim 13, characterized in that, The second spray gun (201) is a three-channel integrated spray gun. It sprays the reducing agent into the slag layer of the side-blowing zone (21) through its inner channel, sprays the oxygen-containing gas into the slag layer of the side-blowing zone (21) through its middle channel, and sprays the reducing agent or the fuel into the slag layer of the side-blowing zone (21) through its outer channel. Alternatively, among the multiple second spray guns (201), some are single-channel spray guns used to spray the reducing agent into the slag layer of the side-blowing zone (21), and others are dual-channel spray guns. They spray the oxygen-containing gas into the slag layer of the side-blowing zone (21) through their inner channel and spray the reducing agent or the fuel into the slag layer of the side-blowing zone (21) through their outer channel. The side-blowing zone (21) is supplemented with heat by a supplementary heating burner (203) to maintain the temperature of the side-blowing zone (21); During the smelting reaction in the molten pool, coke is added to the molten pool.

15. The method for smelting iron-based minerals according to any one of claims 10 to 12, characterized in that, During the electrothermal reduction process, the temperature of the electrothermal zone (22) is controlled to be 1550~1780℃; During the electrothermal reduction process, block-shaped reducing agent is added to the electrothermal zone (22) through the reducing agent feeding port at the top, or the reducing agent is sprayed into the zone through the third spray gun.

16. The smelting method for iron-based minerals according to claim 15, characterized in that, The block reducing agent is one or more of the following: blocky coal, coke, petroleum coke, ferrosilicon, ferromanganese, and ferromanganese. The reducing agent sprayed is a powdered reducing agent and / or a gaseous reducing agent; The fuel is one or more of the following: natural gas, heavy oil, pulverized coal, coal gas, coal-to-gas, hydrogen, coke powder, and gasoline; The oxygen-containing gas is oxygen-enriched air or oxygen; The iron-based minerals are one or more of the following: iron concentrate, vanadium-titanium magnetite, sea sand, high-phosphorus iron ore, laterite nickel ore, and iron-containing solid waste. The flux is a calcium-based flux.

17. The smelting method for iron-based minerals according to claim 16, characterized in that, The reducing agent injected is one or more of pulverized coal, coke powder, petroleum coke powder, graphite powder, natural gas, coal gas, coal gas, and hydrogen; the iron-containing solid waste is one or more of red mud, copper smelting slag, and copper depletion slag; the flux is quicklime and / or limestone; the iron-based minerals and the flux are mixed according to a binary basicity of CaO / SiO2 = 0.5~1.

5.

18. The smelting method for iron-based minerals according to claim 16, characterized in that, Before injecting the iron-based mineral and the flux through the ore injection port (101), the smelting method further includes: dehydrating both the iron-based mineral and the flux until the water content is less than 1 wt%; and grinding both the dehydrated iron-based mineral and the flux until the particle size is less than 150 μm.

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