A method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace

Abstract

The present invention belongs to the field of copper smelting in Ausmelt furnaces, and particularly relates to a method for injecting carbon-rich wind-borne semi-coke into an Ausmelt furnace. Aiming at the problems in the prior art, such as large fly ash content in the central coal gun injection, too fast reaction speed, resulting in large temperature gradient in the molten bath, high viscosity of the molten slag, and slag surge causing gun jamming, etc., the present invention uses semi-coke to replace a part of pulverized coal, and at the same time uses a mixture of CO and CO2 instead of air to inject semi-coke and pulverized coal, so that the temperature difference between the center and the side wall of the molten bath is 70°C to 150°C, the average content of Fe3O4 in the molten slag is 6.5% to 10%, and the average viscosity of the molten slag is 0.5 to 1.0 Pa·s, significantly improving the production situation.

Description

Technical Field

[0001] The invention belongs to the field of copper smelting of an Ausmelt furnace, and in particular relates to a method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace. Background Art

[0002] The core of Ausmelt technology is the spray gun technology, which consists of four specially designed concentric sleeves: the innermost layer is pulverized coal and air (coal-carrying air); the second layer is oxygen; the third layer is air (spray gun air); the outermost layer is sleeve air (sleeve air) to protect the third sleeve wall, and also to assist the combustion of sulfur and other combustible components (mainly CO) in the combustion flue gas generated by smelting in the furnace. During operation, the spray gun is inserted from the top of the furnace into the melt in the vertically placed cylindrical furnace, and air (or oxygen-enriched air) and fuel (oil, natural gas or pulverized coal) are sprayed into the melt from the end of the spray gun, creating a violently churning molten pool surface in the furnace, and the charge is directly added to the churning molten pool from the top feeding port.

[0003] The large pieces of raw coal piled in the coal storage bin are transported to the hammer crusher through the conveyor belt for crushing. After crushing, the coal with a particle size of 30mm is screened through the vibrating screen, and the coal with a particle size of less than or equal to 10mm is sent to the vertical mill through the conveyor belt and the weighing coal feeder. Under the suction force of the centrifugal fan, the hot air in the combustion chamber is drawn into the rotating vertical mill. At this time, the coal with moisture and the hot air undergo a strong heat exchange to obtain dried and ground pulverized coal. The pulverized coal is sent to the bag dust collector for separation and collection under the action of the centrifugal fan. The pulverized coal in the ash hopper of the bag dust collector is collected into the pulverized coal bin through a screw conveyor, and then transported to the pulverized coal bin on the side of the Australian furnace and the fuming furnace through a bin pump. The other part of the pulverized coal is sent to the combustion chamber through a primary fan.

[0004] The processing of pulverized coal is also relatively complicated. It is necessary to control the water content in the pulverized coal. Otherwise, when the water content is greater than 7%, it is very easy to cause the spray gun to be blocked and affect the combustion efficiency. In addition, the pulverized coal itself contains a high ash content, which will increase the slag volume. The main component of the ash is SiO 2 (10%~60%)、Al 2 O 3 (5%~35%), Fe 2 O 3 (4%~25%) and CaO (5%~40%) are not conducive to the flow and separation of slag metal in the molten pool, and will also increase the pressure of the spray gun and the risk of slag surge in the molten gun, as well as the difficulty of slag discharge at the weir, which seriously affects production. Therefore, the pulverized coal needs to be fully burned in the furnace to ensure a sufficiently high temperature in the furnace, but it is necessary to pay attention to cleaning the agglomeration and blockage of the burner outlet, and to prevent the occurrence of malignant accidents such as fire or explosion of pulverized coal and pulverized coal bunker.

[0005] During the smelting process of copper smelting in the Ausmelt furnace, the wetted and mixed materials are added to the molten pool from the top feed port of the furnace, and the fuel (pulverized coal) and combustion air are sprayed in through the spray gun inserted into the molten pool. Pulverized coal is used as both fuel and reducing agent. The furnace temperature is the fundamental guarantee for the normal operation of smelting, but the pulverized coal is extremely fine in particle size, and it is very easy to get blocked when flowing with the coal injection wind in the coal gun, resulting in poor feeding, which is easy to cause excessive pressure, leading to dust explosion and other serious problems that endanger production and personal safety, while reducing the blast speed cannot meet the needs of production intensity. The fast combustion speed of pulverized coal leads to uneven heat transfer in the molten pool. The temperature of the molten pool near the spray gun is high, and the temperature of the molten pool near the furnace wall is low, thus generating a large temperature gradient. The large temperature gradient leads to untimely and inaccurate feedback on the actual temperature of the furnace body, extremely high requirements for operation, low tolerance for production operation, and frequent production accidents that fail to meet production standards. The operation requirement of Ausmelt furnace is a small temperature gradient, that is, the temperature distribution is uniform. A large temperature gradient can easily deteriorate the slag phase composition, making the slag fluidity worse, thus producing foamy slag, slag surge and other phenomena, damaging the furnace lining and spray gun.

[0006] On the other hand, it is necessary to control the Fe content in the slag. 3 O 4 The content of Fe is lower than 15%, and the temperature gradient is large, which is not conducive to the Fe 3 O 4 The reduction process. The grade of copper matte produced by Ausmelt smelting furnace is about 60%, and the removal rate of iron and sulfur is high. FeS in the ore will be oxidized to FeO and Fe 3 O 4 , while Fe 3 O 4 The higher the content, the worse the fluidity of the slag. In a strong oxidizing atmosphere, part of the iron is oxidized to Fe 3 O 4 , Fe 3 O 4 It will deteriorate the properties of the slag, affect the clarification and separation of the slag and the copper matte, and form a furnace agglomerate when deposited at the bottom of the furnace. 3 O 4 The formation of Fe is inevitable. In order to further reduce the Fe 3 O 4 Content, Fe 3 O 4 The pulverized coal is used as a fuel and also as a reducing agent to control the overoxidation of FeO in the slag and reduce Fe 3 O 4 Reduced to FeO, pulverized coal and Fe 3 O 4 The following reaction occurs: 2Fe 3 O4 +C=6FeO+CO 2 However, the reaction speed of pulverized coal is too fast and the reactivity of pulverized coal is too active, which will cause the Fe 3 O 4 Rapidly reduce and reduce its concentration to make it compatible with the Fe in the molten pool slag near the furnace wall. 3 O 4 The existence of concentration gradients also leads to a gradient deterioration in the viscosity of the slag, which makes it extremely difficult to control the oxygen potential in the molten pool and the degree of deterioration of the slag viscosity, resulting in large production fluctuations and difficult operations. Therefore, reducing the temperature gradient, reasonably controlling the melt temperature, and reducing the harm of sticky slag are key issues in production operations. Summary of the invention

[0007] In order to solve the above problems, the present invention provides a method for injecting blue coke carried by carbon-rich wind in an Ausmelt furnace. The top-blowing lance is composed of four layers of concentric sleeves. The innermost central coal lance injects pulverized coal and air, the second layer of oxygen lance injects oxygen, the third layer injects air to form lance wind, and the outermost layer injects air to form sleeve wind. The pulverized coal in the innermost layer of the top-blowing lance is replaced by blue coke, and the injection air in the innermost layer of the top-blowing lance is replaced by carbon-rich gas; the carbon-rich gas includes CO and CO 2 The mixed gas is formed, and the carbon-rich gas is used as a carrier gas and is sprayed into the furnace through a spray gun together with the semi-coke and pulverized coal;

[0008] Preferably, the CO accounts for 40% to 50% of the carbon-rich gas. 2 It accounts for 50% to 60% of the carbon-rich gas; at this time, the semi-coke replaces 40% to 60% (mass percentage) of the pulverized coal; the particle size of the semi-coke is 6mm to 13mm.

[0009] Taking the total amount of charge added per unit time as 150t / h~180t / h as a reference, the top-blowing lance parameters for each ton of charge (i.e. ore + auxiliary materials) are set as follows: the carbon-rich gas back pressure of the innermost center coal gun of the top-blowing lance is 20kPa~30kPa, and the carbon-rich gas supply intensity is 400Nm 3 / (t·h)~500Nm 3 / (t·h); oxygen back pressure of the second layer oxygen gun is 78kPa~90kPa, oxygen supply intensity is 25000Nm 3 / (t·h)~27000Nm 3 / (t·h); The third layer of spray gun wind (air) back pressure is 68kPa~78kPa, and the air supply intensity is 13500Nm 3 / (t·h)~15000Nm 3 / (t·h); the outermost sleeve wind (air) back pressure is 47kPa~52kPa, and the air supply intensity is 7000Nm 3 / (t·h)~7400Nm 3 / (t·h).

[0010] The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace of the present invention comprises the following main steps:

[0011] (1) The semi-coke particles and pulverized coal are mixed through the feeding system and then enter the spray gun through the silo valve;

[0012] (2) copper ore and auxiliary materials are fed into the molten pool, the spray gun is lowered to the specified production height, and the carbon-rich gas pressure of the innermost center coal gun of the spray gun is adjusted to spray, and the semi-coke particles, pulverized coal and carbon-rich gas are sprayed into the melt;

[0013] (3) When the copper matte grade reaches 58%~62%, record the center temperature and side wall temperature of the molten pool and take slag samples for analysis.

[0014] The present invention uses CO 2 The mixed gas of CO and CO is used as "coal-carrying air" instead of air, which has the following advantages: (1) CO 2 The oxidizing rate is higher than O 2 Weak, can weaken O to some extent 2 Strong oxidation effect on the molten pool to prevent excessive conversion of FeO in the molten pool into Fe 3 O 4 ; (2) CO can further 3 O 4 Reduction to reduce its content; (3) CO 2 The molecular diffusion ability of CO is strong, and the stirring effect is stronger than that of air, which helps to speed up the reaction of the molten pool and make the matte-forming reaction and Fe 3 O 4 The redox reaction of CO is more complete; (4) 2 It helps to control the temperature gradient of the molten pool and prevent overheating, thereby reducing volatile metal dust in the fume and reducing copper loss.

[0015] In addition to using the pure CO 2 In addition to the mixed gas of CO and carbon-rich gas, the vented gas can also be used as the carrier gas for injection. The vented gas comes from the steelmaking converter and refers to the by-product gas whose quality does not meet the enterprise's recycling standards. Generally, the CO 2 It has high CO content (25%~45%), low CO content (10%~30%), and physical heat of 400℃~1000℃, which can reduce fuel costs. It is a low-cost, high-quality coal-carrying air alternative.

[0016] The present invention uses granular blue coke to partially replace pulverized coal, which has the following advantages: (1) it will not cause clogging of the spray gun; (2) the combustion speed is slow, which avoids excessive local temperature and is conducive to uniform temperature distribution in the molten pool; (3) the existence time in the molten pool is prolonged, the duration of the reduction reaction is prolonged, and compared with lump coal, it is more evenly dispersed in the molten pool, which helps to uniformly and continuously control the Fe content in the molten pool. 3 O 4 The content is at a low level; (4) The ash content is low and will not increase the amount of slag; (5) The price of lignite is half of that of coal, which reduces costs.

[0017] Raw coal is coal mined from mines, with a larger particle size, generally 50mm~300mm. Powdered coal is coal that has been crushed and processed, with a smaller particle size, generally 0.1mm~6mm. The particle size of granular coal is 6mm~13mm. Coal with a particle size greater than 13mm, which is obtained by falling or crushing raw coal with uneven particle size by a large-scale jaw crusher, is called lump coal. Semi-coke (also known as semi-coke, coke powder) has a block structure and is made from clean coal blocks. The particle size is generally between 10mm~80mm. It has the characteristics of "three highs and four lows", such as high fixed carbon, high specific resistivity, high chemical activity, low ash content, low aluminum, low matte, and low phosphorus, but its strength and crushing resistance are relatively poor. The market price is much lower than that of general coke, and is currently only about half of the price of coking coal. Coke has high strength, low ash content, large particle size, and strong reactivity. However, the price of metallurgical coke is higher than that of raw coal. Therefore, a certain proportion of metallurgical coke can be selected as an alternative raw material for the combination of lignite / raw coal.

[0018] The method of the present invention can control the slow and long-term oxidation process of FeO in the melt by the reducing agent, while retaining a portion of Fe 3 O 4 Slag forming reaction occurs (3Fe 3 O 4 +FeS+5SiO 2 =5(2FeO·SiO 2 )+SO 2 ), rather than completely and quickly removing Fe 3 O 4 The presence of slag significantly improves the fluidity of the slag. After the carbon-rich wind-carried blue charcoal injection method of the present invention is adopted, the temperature difference between the center temperature and the side wall temperature of the molten pool is 70°C to 150°C, and the Fe 3 O 4 The average content is 6.5%~10%, the concentration difference between the center and the side wall is 3%~5%, and the average viscosity of the slag is 0.5Pa·s~1.0Pa·s. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1It is a schematic diagram of the structure of the Ausmelt furnace spray gun in the present invention. DETAILED DESCRIPTION

[0020] The technical scheme of the present invention is clearly and completely described below in conjunction with the embodiments and the accompanying drawings. It should be pointed out that the embodiments described in the present invention are only used to further explain and illustrate, rather than to limit the scope of application. Based on the present invention, all other schemes obtained by those skilled in the art without making creative work belong to the protection scope of the present invention.

[0021] The basic process of copper smelting in the Ausmelt furnace in the embodiment is as follows:

[0022] (1) The ore used in the embodiment is copper sulfide ore, and the main components and contents of the ore are Cu: 22%~25%, S: 26%~31%, Fe: 25%~30%, SiO 2 :5%~7%, CaO:1.5%~3%. The ore is fed into the furnace through the feeding port on one side of the Ausmelt furnace spray gun via a conveyor belt, and the feeding speed is 150t / h~180t / h. Lump coal with a particle size of 30mm~200mm (of which 40mm~100mm accounts for 90%) is fed into the furnace through a conveyor belt, and the lump coal consumption is 1t / h~3t / h. River sand with a particle size of 1mm~3mm (as flux, SiO 2 The content is more than 97%) and is added to the furnace through a conveyor belt. The flux addition rate is 10t / h~20t / h. Lump coal, flux and ore are added to the furnace separately without premixing.

[0023] The specific dosage of each material in the embodiments and comparative examples is as follows: 155 t / h of mineral material, 1.5 t / h of lump coal, and 14 t / h of river sand.

[0024] (2) After lowering the top-blowing spray gun to below the slag surface, there is no need to wait for the raw materials to melt. The top-blowing spray gun can be directly immersed in the molten pool, and the tuyere pressure of the top-blowing spray gun can be adjusted to spray the molten pool.

[0025] In order to further highlight the effect of bottom blowing, the conditions of the top blowing gun in each embodiment and comparative example are the same. The entire charging and blowing process is continuous. The top blowing gun parameters corresponding to each ton of furnace charge (ore + auxiliary materials) are as follows:

[0026] The carbon-rich gas back pressure of the innermost center coal gun is 25kPa, and the carbon-rich gas supply intensity is 450Nm 3 / (t·h); oxygen back pressure of the second layer oxygen gun is 85kPa, oxygen supply intensity is 26000Nm 3 / (t·h); The third layer of spray gun wind (air) back pressure is 75kPa, and the spray gun wind supply intensity is 14000Nm 3 / (t·h); the outermost sleeve wind (air) back pressure is 50kPa, and the sleeve wind supply strength is 7200Nm 3 / (t·h).

[0027] If there is no special explanation, the particle size of the blue charcoal used in the present invention is 6mm~13mm, and the particle size of the pulverized coal is 0.1mm~6mm. When blue charcoal is not used as a substitute and only pulverized coal is sprayed, the amount of pulverized coal in the central coal gun corresponding to each ton of copper concentrate ore powder (i.e., ore material, excluding auxiliary materials) is 15kg~25kg; in the embodiment, when blue charcoal is not used as a substitute and only pulverized coal is sprayed in the central coal gun, the specific amount of pulverized coal is 2.5t / h (16kg pulverized coal per ton of ore material).

[0028] (3) When the copper matte grade reaches 58%, record the center temperature and side wall temperature of the molten pool, release a portion of the copper matte and slag through the weir to enter the subsequent process, so that the molten pool height is maintained at about 2000mm, and take slag samples and copper matte for analysis. The slag viscosity is tested in accordance with the YB / T 185-2017 standard.

[0029] The Ausmelt furnace spray gun structure of the present invention is as follows: Figure 1 shown.

[0030] The above basic process is only an example of the copper smelting related process of the carbon-rich wind-borne blue charcoal injection method in the embodiment of the present invention, and does not limit the basic process applicable to the injection method of the present invention. In production practice, various parameters can be adjusted as needed.

[0031] Example 1: 50% of pulverized coal is replaced by semi-coke, and CO in the carbon-rich air of the central coal gun is 2 Content 60%, CO content 40%.

[0032] (1) There was no sudden increase in coal gun pressure during the injection process, and the injection was smooth;

[0033] (2) The center temperature of the molten pool is 1325°C, the side wall temperature is 1177°C, and the temperature difference between the center and the side wall is about 148°C;

[0034] (3) Average Fe content of slag 3 O 4 The content is 9.8%, the concentration difference between the center and the side wall is about 5.0%, and the viscosity of the slag is about 0.95 Pa·s.

[0035] Example 2: 50% of pulverized coal is replaced by semi-coke, and CO in the carbon-rich air of the central coal gun is 2 Content 55%, CO content 45%.

[0036] (1) The spraying process is smooth without blockage;

[0037] (2) The center temperature of the molten pool is 1315°C, the side wall temperature is 1192°C, and the temperature difference between the center and the side wall is about 123°C;

[0038] (3) Average Fe content of slag 3 O 4 The content is 8.9%, the concentration difference is about 4.7%, and the viscosity drops to 0.86Pa·s.

[0039] Example 3: 50% of pulverized coal is replaced by semi-coke, and CO in the carbon-rich air of the central coal gun is 2 Content 50%, CO content 50%.

[0040] (1) The spraying process is smooth without blockage;

[0041] (2) The center temperature of the molten pool is 1295°C, the side wall temperature is 1212°C, and the temperature difference between the center and the side wall is about 83°C;

[0042] (3) Average Fe content of slag 3 O 4 The content is 7.6%, the concentration difference is about 4.1%, and the viscosity drops to 0.65 Pa·s.

[0043] Example 4 The carbon-rich air of the central coal gun is 50% CO + 50% CO 2 Under the conditions of , the proportion of lignite replacing pulverized coal is reduced to 40%.

[0044] (1) The injection process is smooth and there is no abnormality in the coal gun pressure;

[0045] (2) The center temperature of the molten pool is 1310°C, the side wall temperature is 1203°C, and the temperature difference between the center and the side wall is 107°C;

[0046] (3) Fe in slag 3 O 4 The average content is 9.3%, the concentration difference between the center and the side wall is 4.8%, and the viscosity further drops to 0.78 Pa·s.

[0047] Example 5 The carbon-rich air of the central coal gun is 50% CO + 50% CO 2 Under the conditions of 2017-08-08, the proportion of lignite replacing pulverized coal increased to 60%.

[0048] (1) There was no blockage during the injection process and the coal gun pressure was stable;

[0049] (2) The center temperature of the molten pool is 1290°C, the side wall temperature is 1219°C, and the temperature difference between the center and the side wall is reduced to 71°C;

[0050] (3) Fe in slag 3 O 4 The average content is 6.5%, the concentration difference between the center and the side wall is 3.8%, and the viscosity is reduced to 0.5 Pa·s.

[0051] Comparative Example 1

[0052] The blue coke replaces 50% of the pulverized coal, and the blue coke particle size is 0.1 mm to 6 mm; ordinary air is used as the carrier gas of the central coal gun. The remaining steps are the same as those in Example 1.

[0053] (1) Use semi-coke with a particle size of 0.1 mm to 6 mm for injection. Since the particle size is too small, semi-coke and pulverized coal are easy to aggregate during the injection process, resulting in reduced injection efficiency;

[0054] (2) The coal gun pressure increased abnormally during the injection process, indicating that blockage occurred, affecting the continuity and uniformity of the injection;

[0055] (3) The center temperature of the molten pool is 1340°C, the side wall temperature is 1135°C, and the temperature difference between the center and the side wall is 205°C;

[0056] (4) Fe in slag 3 O 4 The average content is 17.2%, the center-side wall concentration difference is 8.0%, and the viscosity is 1.28 Pa·s.

[0057] Comparative Example 2

[0058] The blue carbon replaces 50% of the pulverized coal, and the blue carbon particle size is 13 mm to 50 mm. Ordinary air is used as the carrier gas. The remaining steps are the same as those in Example 1.

[0059] (1) Using semi-coke with a particle size of 13 mm to 50 mm for spraying, the semi-coke cannot be effectively sprayed into the molten pool due to its large particle size, resulting in poor spraying effect;

[0060] (2) During the injection process, the coal gun pressure was continuously high, and blockages occurred multiple times during the injection process, which seriously affected the injection efficiency;

[0061] (3) The center temperature of the molten pool is 1266°C, the side wall temperature is 1105°C, and the temperature difference between the center and the side wall is 161°C;

[0062] (4) Fe in slag 3 O 4 The average content is 19.0%, the center-side wall concentration difference is 10.5%, and the viscosity is 1.35 Pa·s.

[0063] Comparative Example 3

[0064] The central coal gun only sprays pulverized coal, does not use blue coal as a substitute, and uses ordinary air as a carrier gas. The remaining steps are the same as those in Example 1.

[0065] (1) The pulverized coal has a small particle size, high ash content, and fast reaction speed, which leads to high temperature in the center of the molten pool and uneven heat transfer. Ordinary air is used as the coal-carrying air for injection. The air contains about 21% oxygen, which is not conducive to the reduction reaction.

[0066] (2) The center temperature of the molten pool is 1360°C, the side wall temperature is 1120°C, and the temperature difference between the center and the side wall is 240°C;

[0067] (3) Fe in slag 3 O 4 The average content is 14.7%, the center-side wall concentration difference is 7.7%, and the viscosity is 1.38 Pa·s.

[0068] Comparative Example 4

[0069] The central coal gun only sprays pulverized coal, and does not use semi-coke as a substitute. The central coal gun contains CO 2 The content is 60%, and the CO content is 40%. The remaining steps are the same as in Example 1.

[0070] (1) Pulverized coal has small particle size, high ash content and fast reaction speed. Carbon-rich air is used as coal-carrying air for injection. 2 The reaction is endothermic, the temperature in the center of the molten pool is high and the heat transfer is uneven;

[0071] (2) The center temperature of the molten pool is 1347°C, the side wall temperature is 1152°C, and the temperature difference between the center and the side wall is 195°C;

[0072] (3) Fe in slag 3 O 4 The average content is 13.6%, the center-side wall concentration difference is 6.8%, and the viscosity is 1.19 Pa·s.

[0073] The following conclusions can be drawn from the above embodiments and comparative examples:

[0074] (1) It can be seen from Examples 1 to 3 that when the amount of blue coke replacing pulverized coal is the same, the higher the CO content in the carbon-rich gas, the lower the temperature difference between the center and side walls of the molten pool, and the slag viscosity and Fe 3 O 4 The average concentration and the center-side wall concentration difference are also lower.

[0075] (2) It can be seen from Examples 3 to 5 that when the amount of CO in the carbon-rich gas is the same, the higher the proportion of blue coke replacing pulverized coal, the lower the temperature difference between the center and side walls of the molten pool, and the slag viscosity and Fe 3 O 4 The average concentration and the center-side wall concentration difference are also lower.

[0076] (3) It can be seen from comparative examples 1 to 4 that when air or carbon-rich wind is used as the carrier gas, only pulverized coal is blown, or the particle size of the semi-coke replacing pulverized coal is small or large, the blowing effect is not ideal.

Claims

1. A method for spraying blue carbon with carbon-rich air in an Ausmelt furnace, wherein the top-blowing lance is composed of four layers of concentric sleeves, the innermost central coal lance sprays pulverized coal and air, the second layer oxygen lance sprays oxygen, the third layer sprays air to form lance wind, and the outermost layer sprays air to form sleeve wind, characterized in that: The innermost layer of the pulverized coal in the top-blowing lance is replaced by semi-coke, and the innermost layer of the injection air in the top-blowing lance is replaced by carbon-rich gas; the carbon-rich gas includes a mixed gas composed of CO and CO2, and the carbon-rich gas is used as a carrier gas to be injected into the furnace through the lance together with the semi-coke and pulverized coal; The CO accounts for 40% to 50% of the carbon-rich gas, and the CO2 accounts for 50% to 60% of the carbon-rich gas; the lignite replaces 40% to 60% of the pulverized coal; the particle size of the lignite is greater than 6 mm and less than 13 mm, and the particle size of the pulverized coal is 0.1 mm to 6 mm.

2. The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace according to claim 1, characterized in that: The top-blowing lance parameters corresponding to each ton of charge are as follows: the carbon-rich gas back pressure of the innermost center coal gun of the top-blowing lance is 20kPa~30kPa, and the carbon-rich gas supply intensity is 400Nm 3 / (t·h)~500Nm 3 / (t·h).

3. The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace according to claim 1, characterized in that: The oxygen back pressure of the second oxygen lance of the top-blowing spray gun is 78kPa~90kPa, and the oxygen supply intensity is 25000Nm 3 / (t·h)~27000Nm 3 / (t·h).

4. The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace according to claim 1, characterized in that: The third layer of top-blowing spray gun has a back pressure of 68kPa~78kPa and a gas supply intensity of 13500Nm 3 / (t·h)~15000Nm 3 / (t·h).

5. The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace according to claim 1, characterized in that: The wind back pressure of the outermost sleeve of the top-blowing spray gun is 47kPa~52kPa, and the air supply intensity is 7000Nm 3 / (t·h)~7400Nm 3 / (t·h).

6. The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace according to claim 1, characterized in that: The following steps are involved: (1) Mix the semi-coke and pulverized coal and send them into the top-blowing lance; (2) copper ore and auxiliary materials are fed into the molten pool, and after the top-blowing lance is lowered to the specified production height, the pressure of the carbon-rich gas in the innermost center coal lance of the lance is adjusted for spraying, and the semi-coke, pulverized coal and carbon-rich gas are sprayed into the molten pool; (3) When the copper matte grade reaches 58%~62%, record the center temperature and side wall temperature of the molten pool and take slag samples for analysis.

7. The method for injecting carbon-rich wind-borne semi-coke in an Ausmelt furnace according to claim 2, characterized in that: The furnace charge includes mineral material, coal and sand; the feeding speed is 150t / h~180t / h for mineral material, 1t / h~3t / h for coal and 10t / h~20t / h for sand.

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