Side-blown smelting furnace and smelting method

Abstract

The invention discloses a side-blown smelting furnace and a smelting method, and belongs to the technical field of side-blown smelting. The side-blown smelting furnace comprises a furnace body, wherein the furnace body comprises a furnace bottom, a straight section furnace wall, an expanded section furnace wall connected with the top of the straight section furnace wall and a furnace top from bottom to top; the furnace bottom, the straight section furnace wall, the expanded section furnace wall and the furnace top form a hearth; the furnace bottom and the straight section furnace wall form a molten pool area and a splashing area; at least one gun base water jacket is arranged on the straight section furnace wall, a raw material spray gun is installed on the gun base water jacket, the axis of the raw material spray gun is arranged in the horizontal or nearly horizontal direction, and a nozzle of the raw material spray gun extends into and faces the molten pool area. The raw materials are directly horizontally or nearly horizontally side-blown and sprayed into the molten pool, so that the problems of high smoke dust rate and unreasonable heat energy utilization in smelting of various raw materials are solved, and high-efficiency, low-consumption and stable reinforced smelting is realized.

Description

Technical Field

[0001] This application belongs to the field of side-blown smelting technology, and specifically relates to a side-blown smelting furnace and smelting method. Background Technology

[0002] In the non-ferrous metallurgical industry, side-blown smelting is a modern intensified smelting process. The smelting equipment is known in the industry as a side-blown furnace, applicable to the smelting of various metals such as copper, lead, zinc, nickel, and solid waste. Based on the tuyer structure and heating method, side-blown furnaces can be divided into bubbling-type side-blown furnaces and submerged combustion-type side-blown furnaces. Bubbling-type side-blown furnaces only supply air or oxygen-enriched air to the tuyeres, and the heat balance of the molten pool relies on the self-heating of the raw material reaction or the blending of raw materials with coal. Submerged combustion-type side-blown furnaces, in addition to supplying air or oxygen-enriched air, also supply gaseous fuel, liquid fuel, or solid fuel to the tuyeres, and the heat balance of the molten pool relies on the heat released by fuel combustion. In this case, the tuyeres are generally called lances. Both types of side-blown furnaces have their own characteristics and are currently widely used. Bubbling-type side-blown furnaces are more suitable for sulfide concentrates that can undergo self-heating reactions, while submerged combustion-type side-blown furnaces are more suitable for oxide concentrates or solid waste raw materials that do not generate heat.

[0003] Currently, whether it's a bubbling or submerged combustion side-blown furnace, the main feeding method is through the top feed port. During the feeding process, fine powder in the raw materials is carried away by the upward-flowing flue gas, resulting in dust accumulation and increasing the dust concentration. Therefore, the designed flue gas velocity is generally not allowed to exceed 6 m / s. On the other hand, some self-heating raw materials have the characteristic of being easily volatile when heated, such as antimony sulfide concentrate and zinc sulfide concentrate. These materials will volatilize to a considerable extent during the feeding process in the furnace. These volatilized sulfides then undergo secondary combustion with oxygen in the flue gas or leaked air, heating the upper space of the furnace. However, the amount of raw material received by the molten pool in the lower part of the furnace is reduced, resulting in a decrease in the exothermic oxidation reaction in the molten pool. This leads to insufficient heat and a situation where the furnace is prone to freezing, forcing the furnace to supplement submerged combustion in the molten pool to maintain thermal balance. This obviously results in the unreasonable utilization of heat.

[0004] For example, patent publication number CN103924101A discloses a method and apparatus for producing crude antimony trioxide by oxygen-enriched side-blown volatile molten pool smelting. This method uses antimony-containing materials as raw materials, anthracite, coke, natural gas, or coal gas as supplementary fuels, iron ore and lime as fluxes, and oxygen-enriched air is blown in. After the raw materials are metered, they enter the furnace to react and produce high-temperature flue gas and melt. After the high-temperature flue gas is condensed and dust collected, it is sent to the acid production system to produce acid. The dust obtained from condensation is crude antimony trioxide product and sent to the next process. The high-temperature melt is discharged separately after settling and stratifying in the hearth. The slag can be directly discarded after water quenching. The small amount of antimony matte and crude antimony produced are returned for processing, and the precious antimony is sent to the next process for gold extraction. This method has the following drawbacks: (1) The furnace top material is dropped by belt conveyor. During the dropping process, the fine powder in the raw material will be carried away by the upward-flowing flue gas, thus forming dust and increasing the dust rate. In order to suppress this situation, adding water to the raw material for granulation is an inevitable choice. However, the water added to the raw materials is heated to about 1250°C in the furnace and becomes water vapor, which greatly increases energy consumption; moreover, a considerable proportion of the prepared granules will be broken during the transfer process, which will not actually help to reduce the dust rate. (2) On the other hand, antimony sulfide concentrate has a strong characteristic of volatilization when heated. During the process of feeding into the furnace, about 80-90% of the antimony sulfide will volatilize when heated. The volatilized antimony sulfide will then undergo secondary combustion with oxygen in the flue gas or leaking air, heating the upper space of the furnace. However, the molten pool in the lower part of the furnace only receives 10-20% of the antimony sulfide. The oxidation exothermic reaction in the molten pool is reduced, resulting in insufficient heat and easy to cause the furnace to freeze. To a certain extent, it is necessary to add fuel to the molten pool and rely on submerged combustion to maintain the thermal balance. Obviously, this results in unreasonable use of heat and increased energy consumption.

[0005] Therefore, there is an urgent need in this field for a new side-blown smelting technology that can effectively reduce dust levels, improve thermal energy utilization efficiency, reduce energy consumption, and ensure long-term stable operation of equipment. Summary of the Invention

[0006] To address the aforementioned problems, the main objective of this application is to provide a side-blown smelting furnace and smelting method, which aims to solve the problems of high dust rate and unreasonable heat energy utilization in the smelting of various raw materials by directly horizontally or near-horizontally side-blowing the raw materials into the molten pool, thereby achieving efficient, low-consumption, and stable intensified smelting.

[0007] To achieve the above objectives, one aspect of this application provides a side-blown smelting furnace, comprising a furnace body, the furnace body including, from bottom to top, a furnace bottom, a straight furnace wall, an enlarged furnace wall connected to the top of the straight furnace wall, and a furnace top; the furnace bottom, the straight furnace wall, the enlarged furnace wall, and the furnace top constitute a furnace chamber; the furnace bottom and the straight furnace wall constitute a molten pool area and a splashing area; at least one lance holder water jacket is provided on the straight furnace wall, and a raw material spray gun is installed on the lance holder water jacket, the axis of the raw material spray gun is arranged in a horizontal or near-horizontal direction, and its nozzle extends into and faces the molten pool area.

[0008] Furthermore, the raw material spray gun has a dual-channel structure, including a raw material channel located in the center and an oxygen-enriched air channel located in the outer layer.

[0009] Furthermore, the raw material spray gun has a three-channel structure, including a raw material channel in the center, an oxygen-enriched air channel in the next outermost layer, and a fuel channel in the outermost layer.

[0010] Furthermore, the furnace bottom, from the outside to the inside, includes a steel plate, a clay brick or high-alumina brick pad layer, a ramming material leveling layer, and an anti-arch brick; the furnace top, from the outside to the inside, includes a water jacket and refractory castable; the straight section furnace wall, from the outside to the inside, includes a steel plate, a water jacket, and a refractory material layer; and the enlarged section furnace wall, from the outside to the inside, includes a steel plate and a refractory brick layer.

[0011] Furthermore, the top view projection surface of the side-blown melting furnace is square, circular, or oblong.

[0012] Furthermore, the height of the furnace is 5-8m, and the height of the molten pool zone and the splash zone is 3-5m.

[0013] Furthermore, the raw material spray gun is located at the lower part of the molten pool zone, with a height difference of 600-1500mm from the static liquid surface of the molten pool zone.

[0014] Furthermore, the gun holder water jacket is a cast copper water jacket structure with embedded pipe, and the thickness of the slag layer formed on the hot surface of the gun holder water jacket is 5-10mm.

[0015] On the other hand, this application provides a method for smelting using the aforementioned side-blown smelting furnace, comprising the following steps: The finely ground raw materials are mixed with the carrying gas and injected horizontally or nearly horizontally into the molten pool zone through a raw material spray gun set on the wall of the straight section furnace. Oxygen-enriched air and optional fuel are injected into the molten pool zone through the raw material spray gun, so that the raw materials complete the melting reaction in the flow field of the molten pool.

[0016] Furthermore, the raw materials are selected from volatile, self-heating materials or heat-consuming materials.

[0017] Furthermore, the volatile, self-heating material includes one or more of antimony sulfide concentrate, zinc sulfide concentrate, lead sulfide concentrate, copper sulfide concentrate, or nickel sulfide concentrate.

[0018] Furthermore, the rate at which the raw material is injected into a single nozzle of the raw material spray gun is 0.25-25 t / h.

[0019] Furthermore, the oxygen-enriched air is injected into the molten pool at a speed of 150-300 m / s.

[0020] Compared with the prior art, this application has the following beneficial effects: 1. Significantly reduced dust rate: The raw materials are directly injected into the depth of the molten pool through horizontal or near-horizontal side blowing. The fine powder is captured by the melt, which fundamentally avoids being carried by the flue gas, resulting in a significant reduction in dust rate.

[0021] 2. High efficiency and rational utilization of thermal energy: Volatile and self-heating components react in the molten pool with very low volatilization loss. The oxidation heat of the raw materials themselves can be fully utilized, which can reduce the consumption of auxiliary fuels and even achieve self-heating balance.

[0022] 3. Significantly improved bed capacity: Due to the low dust content, the flue gas design velocity can be increased to over 12m / s, significantly enhancing the processing capacity of smelting furnaces of the same size.

[0023] 4. Long equipment life and reliable operation: The water jacket of the gun holder provides ultimate protection for the spray gun, with a life of 6-12 months. The regular flow field formed by horizontal side blowing improves safety.

[0024] 5. Wide range of applications: The side-blown smelting furnace and smelting method of this application are not only suitable for self-heating raw materials such as antimony sulfide, zinc, lead, copper, and nickel, but can also process heat-consuming raw materials such as laterite and red mud by switching the three-channel spray gun to add fuel, making it highly versatile.

[0025] Other features and effects of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing this application. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 A schematic diagram of the structure of a side-blown melting furnace according to one embodiment of this application is shown.

[0028] The above-mentioned attached figures include the following reference numerals: 1. Furnace bottom, 2. Straight section furnace wall, 3. Enlarged section furnace wall, 4. Furnace top, 5. Gun holder water jacket, 6. Raw material spray gun, 7. Furnace chamber, 8. Side-blown molten pool flow field. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0030] To achieve the above objectives, a first aspect of the embodiments of this application provides a side-blown melting furnace, such as... Figure 1 As shown, the furnace includes a furnace body, which comprises a furnace bottom 1, a straight furnace wall 2, an enlarged furnace wall 3 connected to the top of the straight furnace wall 2, and a furnace top 4 from bottom to top. The furnace bottom 1, the straight furnace wall 2, the enlarged furnace wall 3, and the furnace top 4 constitute the furnace chamber 7. The furnace bottom 1 and the straight furnace wall 2 constitute the molten pool area and the splashing area. At least one gun holder water jacket 5 is provided on the straight furnace wall 2. A raw material spray gun 6 is installed on the gun holder water jacket 5. The axis of the raw material spray gun 6 is arranged in a horizontal or near-horizontal direction, and its nozzle extends into and faces the molten pool area.

[0031] The side-blown smelting furnace of this application sets the raw material spray gun in a horizontal or near-horizontal direction on the straight section of the furnace wall and extends directly into the molten pool. On the one hand, the fine powder can be captured by the strongly stirred molten pool, avoiding the fine powder being carried by the rising flue gas and reducing the dust rate. On the other hand, horizontal blowing can form a regular and stable vortex flow field in the molten pool. Compared with oblique top blowing, it prolongs the residence time and movement path of the raw material in the molten pool, making the smelting reaction more complete.

[0032] Furthermore, by changing the top-feeding method to side-blown injection from the molten pool, the design velocity of the flue gas can be increased, for example, from no more than 6 m / s to over 12 m / s. This allows a smelting furnace of the same area to process more raw materials, thus significantly increasing the design bed capacity. Additionally, this application includes a water jacket for the lance holder, protecting the raw material lance and extending its service life. The side-blown molten pool will have a splash height. The furnace bottom and the straight section furnace wall define the molten pool area and splash zone, while the enlarged section furnace wall and the furnace top define the upper furnace area. The reaction flue gas undergoes secondary combustion here before being discharged from the flue gas outlet at the furnace top.

[0033] In one optional embodiment of this application, the raw material spray gun has a dual-channel structure, including a raw material channel in the center and an oxygen-enriched air channel in the outer layer. For self-heating raw materials that are volatile and self-heating, the raw material spray gun adopts a dual-channel structure, spraying in the raw material and oxygen-enriched air respectively.

[0034] In one optional embodiment of this application, the raw material spray gun has a three-channel structure, including a raw material channel at the center, an oxygen-enriched air channel at the next outermost layer, and a fuel channel at the outermost layer. For heat-consuming raw materials, a three-channel structure is adopted to spray in the raw material, oxygen-enriched air, and fuel respectively.

[0035] In some preferred embodiments of this application, the furnace bottom, from the outside in, includes a steel plate, a clay brick or high-alumina brick pad layer, a ramming material leveling layer, and inverted arch bricks. The furnace top, from the outside in, includes a water jacket and refractory castable. The straight section furnace wall, from the outside in, includes a steel plate, a water jacket, and a refractory layer. The enlarged section furnace wall, from the outside in, includes a steel plate and a refractory brick layer.

[0036] In some optional embodiments of this application, the top view projection surface of the side-blown melting furnace is square, circular, or oblong.

[0037] In some preferred embodiments of this application, the height of the furnace is 5-8m, and the height of the molten pool zone and the splash zone is 3-5m. By reasonably setting the height of the side-blown smelting furnace, splashes can be effectively accommodated to reduce adhesion at the feed inlet, and more space can be created for the secondary combustion of combustible components in the flue gas. The heights of the molten pool zone and the splash zone take into account both physical protection and sufficient reaction of raw materials.

[0038] In a preferred embodiment of this application, the raw material spray gun is located at the lower part of the molten pool zone, with a height difference of 600-1500 mm from the static liquid surface of the molten pool zone. Extensive research has shown that a raw material spray gun at this location is more conducive to forming an ideal vortex flow field, prolonging the reaction time, and also avoiding excessive splashing of the reacting melt. A height difference greater than 1500 mm or less than 600 mm will lead to severe splashing; furthermore, a too-small height difference will reduce the utilization rate of the spraying medium.

[0039] In a preferred embodiment of this application, the gun holder water jacket is a cast copper water jacket structure with embedded tubes, and the slag layer formed on the hot surface of the gun holder water jacket has a thickness of 5-10 mm. By fully enclosing and protecting the raw material lance with the gun holder water jacket, the lance body is isolated from the high-temperature furnace and melt, with only the nozzle exposed, greatly reducing lance burn-out and erosion wear. The water-cooling structure maintains a relatively low temperature zone on the hot surface of the gun holder water jacket, which is a prerequisite for the formation and stabilization of the slag layer. The slag layer further insulates the heat and protects the water jacket body.

[0040] A second aspect of the embodiments of this application provides a method for smelting using the above-described side-blown smelting furnace, comprising the following steps: The finely ground raw materials are mixed with the carrying gas and injected horizontally or nearly horizontally into the molten pool zone through a raw material spray gun set on the wall of the straight section furnace. Oxygen-enriched air and optional fuel are injected into the molten pool zone through the raw material spray gun, so that the raw materials complete the melting reaction in the flow field of the molten pool.

[0041] This application involves directly horizontally or nearly horizontally blowing raw materials into the molten pool. The raw materials can be instantly heated and undergo a process reaction. The gas expands violently and rises, causing the melt to form a vortex-shaped side-blown molten pool flow field. This flow field prolongs the residence time of the raw materials in the molten pool, making the reaction more complete.

[0042] In one optional embodiment of this application, the raw material is a volatile, self-heating material, which may be selected from one or more of antimony sulfide concentrate, zinc sulfide concentrate, lead sulfide concentrate, copper sulfide concentrate, or nickel sulfide concentrate. The volatile, self-heating material can maintain the thermal balance of the molten pool through its own exothermic oxidation reaction. By directly injecting the volatile, self-heating material into the molten pool using the above-described smelting method, volatilization loss is greatly suppressed, and the raw material and its reaction heat are concentrated in the molten pool, significantly improving the thermal balance of the molten pool and reducing the need for external fuel replenishment.

[0043] In one optional embodiment of this application, the raw material is a heat-consuming material, including but not limited to laterite, red mud, vanadium-titanium magnetite, iron-containing waste slag, copper / lead / zinc / nickel / tin / antimony oxide ores, secondary copper-containing waste materials (copper slag, electroplating sludge, etc.), secondary lead-containing waste materials (lead slag, battery lead paste, etc.), secondary zinc-containing waste materials (zinc leaching slag, etc.), secondary nickel-containing waste materials (nickel slag, etc.), and secondary rare and precious waste materials (anode mud, antimony slag, etc.). This method is applicable not only to volatile, self-heating raw materials but also to heat-consuming raw materials. When heat-consuming raw materials are selected, fuel is injected into the molten pool through a raw material spray gun, and the heat released by fuel combustion is used to maintain the thermal balance of the molten pool. Compared with the existing furnace top charging port feeding method, the above smelting method can reduce the dust rate and improve the designed bed capacity.

[0044] In some preferred embodiments of this application, the rate at which the raw material is injected into the molten pool by a single nozzle of the raw material spray gun is 0.25-25 t / h; the oxygen-enriched air is injected into the molten pool at a rate of 150-300 m / s. The raw material can be carried by nitrogen or air during the spray gun transport, and either dilute phase transport or dense phase transport can be used. Specifically, the gas-solid ratio for dilute phase transport is 1 Mm. 3 1-15kg, gas-solid ratio for dense phase transport is 1Mm 3 : 16-40kg.

[0045] 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.

[0046] Example 1 A side-blown melting furnace, the structure of which is referenced Figure 1 The furnace body includes a furnace bottom 1, a straight section furnace wall 2, an enlarged section furnace wall 3 connected to the top of the straight section furnace wall 2, and a furnace top 4. The furnace bottom 1, from the outside in, is composed of steel plates, a high-alumina brick pad layer, a ramming material leveling layer, and double-layered anti-arch bricks, with a total thickness of 1500mm. The straight section furnace wall 2, from the outside in, is composed of steel plates, a water jacket, and a refractory layer, with a total thickness of 500mm. The enlarged section furnace wall 3, from the outside in, is composed of steel plates and a refractory brick layer, with a total thickness of 400mm. The furnace top 4, from the outside in, is composed of a water jacket and refractory castable, with a total thickness of 380mm. A lance holder water jacket 5 is installed on the straight section furnace wall 2 and is a cast copper water jacket structure with embedded pipes. The raw material spray lance 6 is installed on the lance holder water jacket 5 and has a dual-channel structure, including a raw material channel in the center and an oxygen-enriched air channel in the outer layer. The central channel injects finely ground antimony sulfide concentrate, flux, and nitrogen-carrying gas, while the outer channel injects oxygen-enriched air. The top-view projection of the side-blown melting furnace is circular, with an inner diameter of φ1600mm in the straight section and an area of ​​2m². 2 The furnace is equipped with three raw material spray guns. The furnace chamber 7 is formed by the furnace bottom 1, the straight section furnace wall 2, the enlarged section furnace wall 3, and the furnace top 4. The furnace bottom 1 and the straight section furnace wall 2 define the molten pool and the splash zone. The raw material spray gun 6 is located in the lower part of the molten pool zone, with a height difference of 900mm from the static liquid surface. The straight section furnace wall 2 has a height of 3000mm, sufficient to cover the splash height of the side-blown molten pool. The enlarged section furnace wall 3 and the furnace top 4 define the upper part of the furnace chamber 7, with a height of 3650mm.

[0047] A method for smelting antimony sulfide concentrate, implemented using the side-blown smelting furnace of this embodiment, includes the following steps: A single raw material spray gun horizontally delivers 1000 kg / h of finely ground antimony sulfide concentrate and 120 kg / h of lime, carrying 200 Nm³ of nitrogen. 3 / h, dilute phase is transported to the interior of the molten pool zone, while simultaneously, oxygen-enriched air with an oxygen volume concentration of 80% is injected into the molten pool at a speed of 200m / s through the outer channel of the raw material spray gun. After the dual-channel spray gun injects the raw materials required for the reaction into the molten pool, the raw materials are instantly heated and undergo melting, oxidation, slagging, and other process reactions. The furnace temperature reaches 1300℃, and the gas expands and rises violently, driving the melt to form a... Figure 1 The side-blown molten pool flow field 8 shown is a vortex-shaped flow field. This vortex-shaped flow field prolongs the residence time of the raw material in the molten pool, allowing the oxidation reaction to occur fully. The lance holder water jacket is supplied with 4t / h of circulating cooling water, providing sufficient cooling intensity to ensure that slag can be deposited on its hot surface by 5-10mm. After secondary combustion in the upper furnace zone, the reaction flue gas is discharged from the flue gas outlet at the top of the furnace.

[0048] Compared to existing smelting methods that involve charging antimony sulfide concentrate from the furnace top, the antimony sulfide concentrate smelting method of this embodiment can avoid the situation where 80-90% of the antimony sulfide concentrate volatilizes in the furnace, thereby making full use of the calorific value of the antimony sulfide concentrate itself, reducing energy consumption by 50-60%, with significant energy-saving effect. In addition, it also reduces the dust rate and improves the design bed capacity.

[0049] Example 2 A side-blown melting furnace, the structure of which is referenced Figure 1 The furnace body includes a furnace bottom 1, a straight section furnace wall 2, an enlarged section furnace wall 3 connected to the top of the straight section furnace wall 2, and a furnace top 4. The furnace bottom 1, from the outside in, is composed of steel plates, a high-alumina brick pad layer, a ramming material leveling layer, and double-layered anti-arch bricks, with a total thickness of 1500mm. The straight section furnace wall 2, from the outside in, is composed of steel plates, a water jacket, and a refractory layer, with a total thickness of 500mm. The enlarged section furnace wall 3, from the outside in, is composed of steel plates and a refractory brick layer, with a total thickness of 400mm. The furnace top 4, from the outside in, is composed of a water jacket and refractory castable, with a total thickness of 380mm. A lance holder water jacket 5 is installed on the straight section furnace wall 2 and is a cast copper water jacket structure with embedded pipes. The raw material spray lance 6 is installed on the lance holder water jacket 5 and has a three-channel structure, including a raw material channel in the center, an oxygen-enriched air channel in the second outermost layer, and a natural gas channel in the outermost layer. The central channel injects finely ground laterite ore and nitrogen-carrying gas; the secondary outer channel injects oxygen-enriched air; and the outermost channel injects natural gas. The side-blown smelting furnace has a circular top-view projection, with a straight section inner diameter of φ1600mm and an area of ​​2m². 2 The furnace is equipped with three raw material spray guns. The furnace bottom 1 and the straight section furnace wall 2 define the molten pool and splash zone. The raw material spray gun 6 is located in the lower part of the molten pool zone, with a height difference of 900mm from the static liquid surface. The straight section furnace wall 2 is 3000mm high, sufficient to cover the splash height of the side-blown molten pool. The enlarged section furnace wall 3 and the furnace top 4 define the upper furnace area, with a height of 3650mm.

[0050] A method for smelting laterite ore, implemented using the side-blown smelting furnace of this embodiment, includes the following steps: A single raw material spray gun horizontally delivers 1500 kg / h of finely ground and blended laterite ore, carrying 200 Nm³ of nitrogen. 3 / h, the dilute phase is transported to the interior of the molten pool. The secondary outer channel of the raw material lance injects oxygen-enriched air (80% oxygen volume concentration) into the molten pool at a speed of 200 m / s, while the outer channel injects natural gas into the molten pool at a speed of 200 m / s. After the three-channel lance injects the raw materials required for the reaction into the molten pool, the natural gas burns to generate heat, which supplies the laterite ore for melting, reduction, and slagging reactions. The furnace temperature reaches 1450℃, and the gas expands violently and rises, driving the melt to form... Figure 1The side-blown molten pool flow field 8 shown is a vortex-shaped flow field. This vortex-shaped flow field prolongs the residence time of the raw material in the molten pool, allowing the reduction reaction to occur fully. The lance holder water jacket is supplied with 4t / h of circulating cooling water, providing sufficient cooling intensity to ensure that slag can be deposited on its hot surface by 5-10mm. After secondary combustion in the upper furnace zone, the reaction flue gas is discharged from the flue gas outlet at the top of the furnace.

[0051] Compared to existing smelting methods for laterite ore by top-feeding, the smelting method for laterite ore in this embodiment significantly reduces dust emissions, improves the design bed capacity, and eliminates the need for adding water to the raw materials for granulation.

[0052] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A side-blown smelting furnace, characterized in that, The furnace includes a furnace body, which comprises, from bottom to top, a furnace bottom, a straight furnace wall, an enlarged furnace wall connected to the top of the straight furnace wall, and a furnace top; the furnace bottom, the straight furnace wall, the enlarged furnace wall, and the furnace top constitute the furnace chamber; the furnace bottom and the straight furnace wall constitute a molten pool area and a splashing area; at least one lance holder water jacket is provided on the straight furnace wall, and a raw material spray gun is installed on the lance holder water jacket, the axis of the raw material spray gun is arranged in a horizontal or near-horizontal direction, and its nozzle extends into and faces the molten pool area.

2. The side-blown smelting furnace according to claim 1, characterized in that, The raw material spray gun has a dual-channel structure, including a raw material channel in the center and an oxygen-enriched air channel in the outer layer.

3. The side-blown smelting furnace according to claim 1, characterized in that, The raw material spray gun has a three-channel structure, including a raw material channel in the center, an oxygen-enriched air channel in the next outermost layer, and a fuel channel in the outermost layer.

4. The side-blown smelting furnace according to claim 1, characterized in that, The furnace bottom, from the outside in, includes a steel plate, a clay brick or high-alumina brick pad, a ramming material leveling layer, and an inverted arch brick; the furnace top, from the outside in, includes a water jacket and refractory castable; the straight section furnace wall, from the outside in, includes a steel plate, a water jacket, and a refractory material layer; the enlarged section furnace wall, from the outside in, includes a steel plate and a refractory brick layer.

5. The side-blown smelting furnace according to claim 1, characterized in that, The top-view projection of the side-blown melting furnace is square, circular, or oblong.

6. The side-blown smelting furnace according to claim 1, characterized in that, The height of the furnace chamber is 5-8m, and the height of the molten pool zone and the splash zone is 3-5m.

7. The side-blown smelting furnace according to claim 1, characterized in that, The raw material spray gun is located at the lower part of the molten pool zone, with a height difference of 600-1500mm from the static liquid surface of the molten pool zone; the gun holder water jacket is a buried pipe cast copper water jacket structure, and the slag layer formed on the hot surface of the gun holder water jacket has a thickness of 5-10mm.

8. A method for smelting using a side-blown smelting furnace as described in any one of claims 1 to 7, characterized in that, Includes the following steps: The finely ground raw materials are mixed with the carrying gas and injected horizontally or nearly horizontally into the molten pool zone through a raw material spray gun set on the wall of the straight section furnace. Oxygen-enriched air and optional fuel are injected into the molten pool zone through the raw material spray gun, so that the raw materials complete the melting reaction in the flow field of the molten pool.

9. The method according to claim 8, characterized in that, The raw materials are selected from volatile, self-heating or heat-consuming raw materials; the volatile, self-heating raw materials include one or more of antimony sulfide concentrate, zinc sulfide concentrate, lead sulfide concentrate, copper sulfide concentrate or nickel sulfide concentrate.

10. The method according to claim 8, characterized in that, The rate at which the raw material is injected into the molten pool by a single nozzle of the raw material spray gun is 0.25-25 t / h; the oxygen-enriched air is injected into the molten pool at a speed of 150-300 m / s.

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