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CN-122012830-A - Method for reducing and eliminating center accumulation of blast furnace smelting hearth of high-titanium vanadium titano-magnetite

CN122012830ACN 122012830 ACN122012830 ACN 122012830ACN-122012830-A

Abstract

The invention provides a method for reducing and eliminating the accumulation of the center of a blast furnace smelting hearth of high-titanium vanadium titano-magnetite, which is characterized in that a titanium-free metallized pre-reduced pellet is added to the center of the blast furnace during material distribution, and the metallized pre-reduced pellet comprises the following components ：TFe75~90%,C：2~4%,P：0.005%,S：0.004%,SiO 2 ：2.5~4.5%,Al 2 O 3 ：2.2~4%,MgO：0.5~1.2%,CaO：0.2~0.8%,Mn：0.05~0.15%. in percentage by mass.

Inventors

  • JIANG SHENG
  • ZHANG LILI
  • LING XINKE
  • Pu Shuiqiang

Assignees

  • 攀钢集团攀枝花钢铁研究院有限公司

Dates

Publication Date
20260512
Application Date
20260324

Claims (10)

  1. 1. A method for reducing and eliminating the center accumulation of a blast furnace smelting hearth of high-titanium vanadium titano-magnetite is characterized in that when the material is distributed, independently adding a titanium-free metallized pre-reduced pellet into the center of the blast furnace; The metallized pre-reduced pellet comprises the following components in percentage by mass: TFe75~90%,C：2~4%,P：0.005%,S：0.004%,SiO 2 ：2.5~4.5%,Al 2 O 3 ：2.2~4%,MgO：0.5~1.2%,CaO：0.2~0.8%,Mn：0.05~0.15%.
  2. 2. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium type vanadium titano-magnetite according to claim 1, wherein the content of TiO 2 of smelting slag of the high titanium type vanadium titano-magnetite is 20-25%.
  3. 3. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium type vanadium titano-magnetite according to claim 1, wherein the metallization ratio of the metallized pre-reduced pellet is 75-95%.
  4. 4. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium type vanadium titano-magnetite according to claim 1, wherein the distribution angle of the metallized pre-reduced pellet is 10-28 °.
  5. 5. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium type vanadium titano-magnetite according to claim 1, wherein the addition mode of the metallized pre-reduced pellets is that each batch of the metallized pre-reduced pellets are added during blast furnace feeding, and the addition amount of the metallized pre-reduced pellets is 1-20% of the batch weight.
  6. 6. The method for reducing and eliminating the center stack of the blast furnace smelting hearth of the high titanium vanadium titano-magnetite according to claim 1, wherein the center stack of the blast furnace smelting hearth of the high titanium vanadium titano-magnetite is determined according to the Ti, si content and the matching degree of the air quantity and the air pressure, and the stack degree is divided into general stack, medium stack and serious stack.
  7. 7. The method for reducing and eliminating the center stack of a blast furnace smelting hearth of high titanium vanadium titano-magnetite according to claim 6, wherein the difference between the mass fraction of Ti and the mass fraction of Si in molten iron is a%, the air quantity is b m 3 /min, and the air pressure is c kPa; When a is more than or equal to-0.08 and less than or equal to 0, and when b is more than or equal to-10 and less than or equal to-5, the stacking is common; when a is more than or equal to-0.08 and less than or equal to-0, and b is more than or equal to-60 and less than or equal to-10 multiplied by c < -10 >, the pile is medium; when a is more than or equal to-0.08 and less than or equal to-0, and b is more than or equal to-100 and less than or equal to-10 multiplied by c < -60 >, the accumulation is serious.
  8. 8. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium vanadium titano-magnetite according to claim 6 or 7, wherein the distribution angle of the metallized pre-reduced pellets is 20-28 ° in a general stack state, 15-20 ° in a medium stack state, and 10-15 ° in a severe stack state.
  9. 9. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium vanadium titano-magnetite according to claim 6 or 7, wherein the addition amount of the metallized pre-reduced pellet is 1-8% of the batch weight in a general stack state, 8-13% of the batch weight in a medium stack state, and 13-20% of the batch weight in a serious stack state.
  10. 10. The method for reducing and eliminating center stack of blast furnace smelting hearth of high titanium type vanadium titano-magnetite according to claim 1, wherein the metallized pre-reduced pellets are continuously added for 2-7 days.

Description

Method for reducing and eliminating center accumulation of blast furnace smelting hearth of high-titanium vanadium titano-magnetite Technical Field The invention belongs to the technical field of ferrous metallurgy, and particularly relates to a method for reducing and eliminating center accumulation of a blast furnace smelting hearth of high-titanium vanadium titano-magnetite. Background The Pan steel belongs to high titanium type vanadium titano-magnetite blast furnace smelting, and the content of TiO 2 in blast furnace slag is up to 20-25%. In the smelting process, tiO 2 in the slag is easy to be reduced to generate high-melting-point phases such as TiC, tiN, solid solution Ti (C, N) thereof and the like, so that the slag is sticky, if the slag cannot be discharged in time, the high-melting-point substances are accumulated in the center of a hearth to form sticky mixture, and are accumulated in the center of the hearth to form hearth accumulation, so that abnormal temperature field and airflow distribution in the hearth are caused, slag iron is not separated, and normal smelting of the blast furnace is seriously influenced. The center of the hearth is the place which is most difficult to reach by high-temperature gas flow, so that the center accumulation of the hearth is most easy to form in the blast furnace smelting process. Aiming at the problems, a plurality of methods are explored in practice by iron and steel enterprises, such as a method for evaluating the residual slag and iron in the hearth by using a model so as to ensure the normal operation of the hearth, the application of heat transfer boundary inverse solution in the corrosion diagnosis of the hearth of the blast furnace, the technical thought of managing the working state of the hearth of the blast furnace by using a mathematical model, and the accumulation and stability of the hearth are ensured by constructing the mathematical model. Some enterprises evaluate the hearth accumulation of the blast furnace from the water temperature difference and the heat load, but the methods are to perform accumulation monitoring on the hearth, in the aspect of eliminating the hearth accumulation, fluorite, scrap steel and the like are mainly added, the fluorite adding mode can improve the content of CaF 2 in the slag, reduce the viscosity of the slag and improve the fluidity of the slag, so that the hearth accumulation is gradually eliminated, but the fluorite enters the furnace and is discharged along with the slag, and larger environmental pollution is caused. Disclosure of Invention The invention aims to provide a method for reducing and eliminating the center accumulation of a high-titanium vanadium titano-magnetite blast furnace smelting hearth, which not only solves the technical problem of rapidly reducing and eliminating the center accumulation of the hearth, but also can improve the yield and smelting strength of the blast furnace and reduce the pig iron cost. The invention provides a method for reducing and eliminating the accumulation of the center of a blast furnace smelting hearth of high titanium type vanadium titano-magnetite, wherein during material distribution, a titanium-free metallized pre-reduced pellet is independently added into the center of the blast furnace; The metallized pre-reduced pellet comprises the following components in percentage by mass: TFe75~90%,C：2~4%,P：0.005%,S：0.004%,SiO2：2.5~4.5%,Al2O3：2.2~4%,MgO：0.5~1.2%,CaO：0.2~0.8%,Mn：0.05~0.15%. Preferably, the TiO 2 content of the smelting slag of the high-titanium vanadium titano-magnetite is 20-25%. Preferably, the metallization ratio of the metallized pre-reduced pellets is 75-95%. Preferably, the distribution angle of the metallized pre-reduced pellets is 10-28 degrees. Preferably, the addition mode of the metallized pre-reduction pellets is that each batch of pellets are added during blast furnace feeding, and the addition amount of the metallized pre-reduction pellets is 1-20% of the batch weight of the material. Preferably, the degree of accumulation of the center of the blast furnace smelting hearth of the high titanium type vanadium titano-magnetite is determined according to the Ti and Si content and the air quantity and air pressure matching degree, and the degree of accumulation is divided into general accumulation, medium accumulation and serious accumulation. Preferably, the difference between the mass fraction of Ti and the mass fraction of Si in molten iron is a%, the air quantity is b m 3/min, and the air pressure is c kPa; When a is more than or equal to-0.08 and less than or equal to 0, and when b is more than or equal to-10 and less than or equal to-5, the stacking is common; when a is more than or equal to-0.08 and less than or equal to-0, and b is more than or equal to-60 and less than or equal to-10 multiplied by c < -10 >, the pile is medium; when a is more than or equal to-0.08 and less than or equal to-0, and b is more than or equal to-100 and le