A smelting reduction vessel lance

Abstract

The application discloses a smelting reduction furnace spray gun, which is used for spraying solid furnace charges and belongs to the technical field of smelting reduction furnaces. The spray gun is a combined component, and from outside to inside, the spray gun is sequentially provided with a water-cooling jacket, a water-cooling sleeve and a core pipe. The core pipe is used for spraying solid raw materials into the smelting reduction furnace. The front end of the core pipe is the inlet of the solid raw materials, and the rear end of the core pipe is the outlet of the solid raw materials. The water-cooling sleeve and the core pipe are arranged to form an annular cavity. The front end of the annular cavity is provided with a water mist inlet, and the rear end of the annular cavity is provided with a water mist outlet. The rear end of the water-cooling sleeve extends out of the water-cooling jacket, and the rear end of the core pipe extends out of the water-cooling sleeve. The spray gun is installed on the side wall of the smelting reduction furnace, penetrates through the side wall and extends into the smelting reduction furnace in an oblique downward direction, and the outlet is located in the slag layer. The spray gun has the advantages that the spray gun head is cooled by water mist, the slag is condensed at the outlet of the spray gun, the length of the spray gun is effectively prolonged, the splashing of liquid slag iron particles into the blast furnace is improved, and the heat transfer efficiency is improved.

Description

Technical Field

[0001] This utility model relates to a molten reduction furnace spray gun, used for spraying solid raw materials, and belongs to the field of molten reduction technology. Background Technology

[0002] The melting reduction furnace mentioned is usually called Hismelt.

[0003] The molten reduction furnace directly uses iron ore powder and coal powder for ironmaking, eliminating the coking and sintering processes. In molten reduction ironmaking, the ore powder and coal powder are directly injected into the slag-iron molten pool, where a reduction reaction occurs, generating CO. The rising CO from the molten pool, along with the injected iron ore powder and coal powder carrier gas, carries the molten slag and iron droplets into the upper space, forming a "fountain" of slag-iron droplets. The rising CO gas and the hot air injected from the top hot air lance undergo a secondary combustion reaction, generating a large amount of heat. The heated "fountain" of slag-iron droplets carries the heat back to the molten pool.

[0004] Liquid slag and iron particles are sprayed from the molten pool into the upper combustion zone, where they are heated. The high-temperature liquid slag and iron particles carry the heat back to the molten pool. The deeper the spray gun is inserted into the molten pool, the higher the liquid slag and iron particles are sprayed, and the better the heat transfer efficiency. However, when the spray gun is inserted too deeply, the tip of the spray gun is closer to the molten iron layer, and the cooling water of the spray gun cannot guarantee sufficient cooling of the spray gun, which may cause the spray gun to burn out and leak water. Summary of the Invention

[0005] Technical problems to be solved

[0006] With a safe space between the nozzle and the molten iron layer, the nozzle outlet is extended to improve heat transfer efficiency.

[0007] Methods for solving technical problems

[0008] A molten reduction furnace spray gun is provided. The spray gun is an assembly consisting of, from the outside in, a water-cooled outer jacket, a water-cooled sleeve, and a core tube. The core tube is used to spray solid raw materials into the molten reduction furnace. The front end of the core tube is the inlet of the solid raw materials, and the rear end of the core tube is the outlet of the solid raw materials. An annular cavity is formed between the water-cooled sleeve and the core tube. The front end of the annular cavity has a water mist inlet, and the rear end of the annular cavity has a water mist outlet. The rear end of the water-cooled sleeve extends out of the water-cooled outer jacket, and the rear end of the core tube extends out of the water-cooled sleeve. The spray gun is installed on the side wall of the molten reduction furnace, and the spray gun penetrates the side wall and extends obliquely downward into the molten reduction furnace. The outlet is located within the slag layer.

[0009] Preferably, the core tube material is: wear-resistant alloy; or composite bimetal; or a steel tube lined with ceramic.

[0010] Preferably, the width of the annular cavity is 1 to 5 mm.

[0011] Preferably, the water mist inlet can also be vented with water mist and nitrogen gas, which are then sprayed out together from the rear end, cooling the rear end of the core tube.

[0012] Preferably, the water consumption for a single spray gun is 0.1~2 t / h.

[0013] Preferably, a solidified slag tube is formed at the rear end of the spray gun, extending the length of the spray gun. Water mist is sprayed out through a high-pressure water atomizing nozzle. The sprayed water mist and nitrogen gas are ejected from the rear end at a certain speed through the annular cavity. Due to the cooling effect of the water mist, the molten slag at the core tube outlet of the spray gun cools down and adheres to the spray gun head, forming a slag tube, which is equivalent to extending the spray gun, bringing the spray gun outlet closer to the molten iron layer, increasing the splash height of liquid slag-iron particles, and improving the heat transfer effect.

[0014] Preferably, the spray guns are evenly arranged around the furnace body of the molten reduction furnace, with a total of ≥2 spray guns; the spray guns are at an angle of 45-55° to the horizontal plane and extend into the slag layer; the lowest point of the spray gun is about 200mm (vertical distance) from the upper edge of the molten iron layer.

[0015] Preferably, the solid raw materials sprayed by the spray gun include iron ore powder, coal powder, solvent, etc., and the solvent is lime, dolomite, etc.; the iron ore powder includes all iron-containing materials.

[0016] Preferably, the gas used to propel the solid raw material through the spray gun is an inert gas. The inert gas includes nitrogen, CO2, coal gas, etc.

[0017] The advantages are: by cooling the spray gun head with water mist, the slag condenses at the spray gun outlet, which is equivalent to extending the spray gun length, improving the splashing of liquid slag and iron particles into the blast furnace, and improving the heat transfer efficiency. Attached Figure Description

[0018] Figure 1 A schematic diagram of a melting reduction furnace

[0019] Figure 2 A schematic diagram of a molten reduction furnace spray gun

[0020] Legend markings

[0021] 1. Spray gun; 2. Water-cooled jacket; 3. Water-cooled sleeve; 4. Core tube; 5. Annular cavity; 6. Solid raw material inlet; 7. Solid raw material outlet; 8. Water mist inlet; 9. Water mist outlet; 10. Molten iron layer; 11. Slag layer; 12. Slag tube; 13. Melting and reduction furnace Specific Implementation

[0022] Example 1

[0023] The following is an appendix Figure 1 , 2For reference, the implementation of this utility model patent is described in detail so that those skilled in the art can easily implement it. This utility model patent can be embodied in many different forms and is not limited to this description.

[0024] Oxygen-containing gas is injected from the top of the molten reduction furnace 13. Iron ore powder, coal powder, and solvent are injected from the side wall through the solid material spray gun 1. The solid material is sprayed into the slag layer 11 by the spray gun 1, and the solid material and conveying gas rush towards the molten iron layer 10 at high speed. The CO and H2 generated by the reaction in the molten pool, as well as the conveying gas, spray the liquid slag-iron particles in the molten pool into the upper space. In the upper space, CO and H2 burn with the oxygen-containing gas, and the heat generated by the combustion heats the slag-iron particles splashed into the upper space. The heated slag-iron particles carry the heat back to the molten pool. The reaction in the molten pool produces molten iron and slag. The slag is discharged through the slag outlet at regular intervals, and the molten iron is discharged through the fore-furnace at regular intervals or continuously. The waste gas generated by the molten reduction furnace 13 is used as fuel or reducing agent after waste heat utilization and dust removal purification.

[0025] The solid material spray gun 1 is an assembly consisting of, from the outside in, a water-cooled outer jacket 2, a water-cooled sleeve 3, and a core tube 4. The core tube is used to spray solid raw materials into the molten reduction furnace. The front end of the core tube 4 is the solid raw material inlet 6, and the rear end of the core tube is the solid material outlet 7. There is an annular cavity 5 between the water-cooled sleeve and the core tube. The front end of the annular cavity 5 has a water mist inlet 8, and the rear end of the annular cavity 5 has a water mist outlet 9. The rear end of the water-cooled sleeve 3 extends out of the water-cooled outer jacket 2, and the rear end of the core tube 4 extends out of the water-cooled sleeve 3. The spray gun is installed on the side wall of the molten reduction furnace 13, and the spray gun penetrates the side wall and extends obliquely downward into the molten reduction furnace 13. The outlet is located in the slag layer 11.

[0026] The inner side of the water-cooled jacket 2 is filled with refractory material; the front end of the water-cooled sleeve 3 is made of copper material, and the outer side of the water-cooled sleeve 3 is cast with concave and convex square grids, which is conducive to slag adhesion and reduces heat loss.

[0027] Iron ore powder, coal powder, lime and dolomite are transported in the core tube 4, which causes severe wear on the core tube. The core tube 4 is made of composite bimetal, with a steel pipe as the base and a wear-resistant layer of centrifugally cast nickel-chromium alloy.

[0028] Water mist is sprayed out through a high-pressure water atomizing nozzle and enters the annular cavity 5 through the water mist inlet 8. In order to increase the speed of the water mist at the water mist outlet 9 of the annular cavity 5, the width of the annular cavity 5 is selected to be 2mm.

[0029] Water mist inlet 8 can also be used to introduce water mist and nitrogen, which are then sprayed out together from water mist outlet 9 at the rear end.

[0030] The spray gun 1 has a solidified slag tube at its rear end, extending the length of the spray gun. The sprayed water mist and nitrogen gas are ejected from the water mist outlet 9 at the rear end through the annular cavity 5 at a certain speed. Due to the cooling effect of the water mist, the molten slag at the spray gun outlet cools down and adheres to the spray gun head, forming a slag tube 12, which is equivalent to an extended spray gun. This makes the spray gun outlet closer to the molten iron layer, increases the splash height of liquid slag-iron particles, improves the heat transfer effect, and increases the service life of the spray gun 1.

[0031] Iron ore powder, coal powder, lime and dolomite are sprayed into the slag layer 11 of the molten reduction furnace 13 through a spray gun 1 using nitrogen as a carrier.

[0032] Example 2

[0033] The difference from Example 1 is as follows:

[0034] Firstly, the width of the annular cavity 5 is selected to be 1mm; secondly, the core tube is made of steel pipe lined with ceramic.

Claims

1. A lance for a molten reduction furnace, characterized in that, The spray gun is an assembly consisting of, from the outside in, a water-cooled outer jacket, a water-cooled sleeve, and a core tube. The core tube is used to spray solid raw materials into the molten reduction furnace. The front end of the core tube is the inlet for the solid raw materials, and the rear end is the outlet. An annular cavity is formed between the water-cooled sleeve and the core tube. The front end of the annular cavity has a water mist inlet, and the rear end has a water mist outlet. The rear end of the water-cooled sleeve extends out of the water-cooled outer jacket, and the rear end of the core tube extends out of the water-cooled sleeve. The spray gun is installed on the side wall of the molten reduction furnace, and extends obliquely downwards through the side wall into the furnace, with the outlet located within the slag layer.

2. The molten reduction furnace spray gun as described in claim 1, characterized in that, The core tube material is: wear-resistant alloy; or composite bimetal; or a steel tube lined with ceramic.

3. The molten reduction furnace spray gun as described in claim 1, characterized in that, The width of the annular cavity is 1 to 5 mm.

4. The molten reduction furnace spray gun as described in claim 1, characterized in that, The water mist inlet can also be used to introduce water mist and nitrogen gas. The nitrogen gas and water mist are sprayed out together from the rear end, and the water mist cools the rear end of the core tube.

5. A molten reduction furnace spray gun as described in claim 1, 2, or 4, characterized in that, The rear end of the spray gun core tube forms a solidified slag tube, extending the length of the spray gun.

6. The molten reduction furnace spray gun as described in claim 1, characterized in that, The solid raw materials include iron ore powder, coal powder, and solvent.

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