CN-121975985-A - Smelting reduction smelting furnace

CN121975985ACN 121975985 ACN121975985 ACN 121975985ACN-121975985-A

Abstract

The invention belongs to the field of smelting reduction iron making, in particular to a smelting reduction furnace, compared with the prior art, the technical proposal of the invention has the advantages that oxygen is directly sprayed into a slag layer, in order to prevent the oxygen sprayed into the slag layer from contacting with the molten iron layer below the molten bath slag layer, the molten iron is reoxidized, the spraying position of the oxygen is arranged at the upper part of the slag layer, and the thickness of the slag layer is kept to be 1000mm-1500mm below the spraying point of the oxygen. The smelting reduction smelting furnace of the invention carries out combustion reaction on CO and H 2 generated by the reaction of oxygen in the slag layer and the molten pool and coal dust sprayed into the molten pool, and the generated heat is directly absorbed by the slag layer, thereby effectively improving the heat efficiency and the production efficiency of iron-containing materials and reducing the unit consumption of pig iron coal dust by 30kg.

Inventors

YAO CHAOSHENG
YU GUOHUA
JIA LIJUN
ZHAO SHIJIE
GUO CHUNLEI

Assignees

山东省冶金设计院股份有限公司

Dates

Publication Date: 20260505
Application Date: 20260310

Claims (10)

1. A smelting reduction furnace for producing molten iron from iron-bearing material using a molten bath-based smelting process, the smelting reduction furnace comprising: The smelting furnace main body (1) comprises a side wall (11) of the smelting furnace main body, a molten pool (12) for containing molten iron and slag and a gas space (13) positioned above the molten pool (12), wherein a molten iron layer (100) and a slag layer (200) are arranged in the molten pool (12); The material spray gun (2) is inserted into the slag layer (200) and is used for spraying materials containing iron materials and carbon materials, wherein the number of the material spray gun (2) is at least 2; The first oxygen-containing gas spray gun (3) is inserted into the upper part of the slag layer (200), and the thickness of the slag layer is kept 1000mm-1500mm below an oxygen spraying point and is used for spraying oxygen-containing gas, wherein the number of the first oxygen-containing gas spray gun is 2-30; a gas outlet (4) which is arranged above the smelting furnace main body (1) and communicated with the gas space (13) and is used for promoting the gas to flow out of the gas space (13); A forehearth (5) connected to the molten bath (12) for tapping molten iron from the molten bath (12) during a smelting operation; A slag tap (6) provided on the smelting furnace body (1) for tapping slag from the bath (12) during a smelting operation.
2. The smelting furnace according to claim 1, characterized in that a second oxygen-containing gas lance (7) is provided, the second oxygen-containing gas lance (7) extending downwardly through the top or side wall opening of the main furnace body (1) and injecting oxygen-containing gas into the gas space (13) above the molten bath (12); The second oxygen-containing gas spray gun (7) has at least one branch.
3. The smelting furnace for smelting reduction according to claim 1, wherein the number of the first oxygen-containing gas injection lances (3) is 12 to 30 and is uniformly distributed around the axis of the main body (1) of the smelting furnace.
4. The smelting furnace according to claim 2, wherein the second oxygen-containing gas lance (7) injects oxygen-enriched hot air into the main body (1) of the smelting furnace.
5. The smelting furnace according to claim 1, wherein the first oxygen-containing gas lance (3) injects oxygen-containing gas and pulverized coal simultaneously.
6. The smelting furnace for smelting reduction according to claim 1 or 5, wherein the first oxygen-containing gas lance (3) is inserted from a side wall (11) of the main body of the smelting furnace corresponding to the position of the slag layer (200) and has an included angle of-10 DEG to +30 DEG with the horizontal plane.
7. The smelting furnace according to claim 1 or 5, wherein the first oxygen-containing gas lance (3) is inserted obliquely downward from a side wall (11) of the furnace body corresponding to the gas space (13), and an outlet of the first oxygen-containing gas lance (3) is in the slag layer (200).
8. The smelting furnace according to claim 1, wherein the outlet of the first oxygen-containing gas lance (3) is located below the slag notch (6) and has a vertical height from the slag notch of 500mm to 1500mm.
9. The smelting furnace for smelting reduction according to claim 1, wherein the material spray gun (2) penetrates through the opening of the side wall (11) of the main body of the smelting furnace and is inclined downwards, and the included angle between the material spray gun and the central line of the main body (1) of the smelting furnace is 30-60 degrees.
10. The smelting furnace according to claim 1, wherein the side wall (11) of the main body of the smelting furnace comprises an upper cylindrical section (111), a transition section (112) and a lower cylindrical section (113) which are sequentially arranged from top to bottom, and the diameter of the lower cylindrical section (113) is larger than that of the upper cylindrical section (111); preferably, the outlet of the forehearth (5) highly meets the working pressure requirement of the smelting reduction furnace, and the forehearth (5) is a siphon tapping device.

Description

Smelting reduction smelting furnace Technical Field The invention belongs to the field of smelting reduction iron making, and particularly relates to a smelting reduction furnace. Background The smelting reduction smelting furnace can directly adopt iron ore powder and coal dust for iron making. In the prior art, for example, chinese patent document CN118773390A, CN111635972a, iron ore powder and coal powder are sprayed into a slag iron bath, a reduction reaction occurs in the bath, oxygen-containing gas is sprayed into a space above the bath of the smelting furnace from the upper part of the smelting furnace, CO and H 2 generated by the reduction reaction of the bath are sprayed into the space above the bath, CO and H 2 are combusted with oxygen in the space above the bath of the smelting furnace to release heat and exchange heat with a slag iron drop fountain formed when CO and H 2 are sprayed from the bath. When the heated slag iron drops down, heat is brought back to the molten pool, which is a source of heat for the molten pool. The heat exchange mode has the defects that the heating temperature rise of each droplet in the upper space is only 3-10 ℃ and the heat efficiency is low. No solution is given in the existing disclosures for the drawbacks of the prior art. Disclosure of Invention In order to solve the technical problems, the invention provides a smelting furnace for smelting reduction, which directly enables CO and H 2 generated by the reaction of oxygen in a slag layer and a molten pool and coal dust sprayed into the molten pool by the material spray gun to perform combustion reaction by directly inserting the material spray gun and the first oxygen-containing gas spray gun into the slag layer at the same time, so that heat generated by the reaction is directly absorbed by the slag layer, the rate thermal efficiency is effectively improved, and the energy consumption of heat supply of the smelting reduction reaction is reduced. The technical problem to be solved by the invention is realized by adopting the following technical scheme that a smelting reduction smelting furnace is used for producing molten iron from iron-containing materials by using a smelting process based on a molten pool, and comprises the following steps: The smelting furnace main body comprises a side wall of the smelting furnace main body, a molten pool for accommodating molten iron and slag and a gas space positioned above the molten pool, wherein a molten iron layer and a slag layer are arranged in the molten pool; the material spray gun is inserted into the slag layer and is used for spraying materials containing iron materials and carbon materials, wherein the number of the material spray gun is at least 2; The first oxygen-containing gas spray gun is inserted into the upper part of the slag layer, and the thickness of the slag layer of 1000mm-1500mm is kept below an oxygen spraying point and is used for spraying oxygen-containing gas, wherein the number of the first oxygen-containing gas spray gun is 2-30; the gas outlet is arranged above the smelting furnace main body and communicated with the gas space and is used for promoting gas to flow out of the gas space; A forehearth connected to the molten bath for discharging molten iron from the molten bath during a smelting operation; a slag tap, provided on the main body of the smelting furnace, for discharging slag from the molten bath during a smelting operation. Preferably, the invention is also provided with a second oxygen-containing gas spray gun which extends downwards through the top or side wall opening of the smelting furnace main body and sprays oxygen-containing gas into the gas space above the molten pool; The second oxygen-containing gas spray gun has at least one branch. Because the residual CO and H 2 still exist and are sprayed out of the molten pool and form a slag iron drop fountain, in order to efficiently utilize the residual CO and H 2, oxygen-containing gas is sprayed into a gas space above the molten pool through a second oxygen-containing gas spray gun, and heat generated by burning the gas space with CO and H 2 can be further used as the supplement of the heat of the molten pool. According to the invention, the number of the first oxygen-containing gas spray guns is 12-30, and the first oxygen-containing gas spray guns are uniformly distributed around the axis of the main body of the smelting furnace, so that the spraying uniformity of the oxygen-containing gas is improved, and the slag layer can be heated more uniformly. In the invention, preferably, the second oxygen-containing gas spray gun sprays oxygen-enriched hot air into the smelting furnace main body so as to enhance the heating effect. In the invention, preferably, the first oxygen-containing gas spray gun sprays oxygen-containing gas and coal dust at the same time so as to improve combustion efficiency. In the invention, preferably, the first oxygen-containing gas spray gun is inserte