CN-122012855-A - LF refining method for non-thermal state casting surplus recovery heat

Abstract

The invention discloses an LF refining method for recycling hot surplus heat, which comprises the following steps of crushing 80-ferrovanadium smelting lean slag, drying, conveying the lean slag to an LF refining high-level bin for standby through a feeding belt, adding a proper amount of 80-ferrovanadium smelting lean slag into the high-level bin for auxiliary slagging after adding a conventional slagging material in the LF refining process, and obtaining qualified molten steel through subsequent LF refining desulfurization, temperature adjustment and fine adjustment. The invention effectively solves the problems of difficult slag formation, high slag formation cost and low desulfurization efficiency of the heat without thermal state casting surplus recovery in the LF refining process, and simultaneously realizes the recovery and utilization of 80 ferrovanadium smelting lean slag and reduces the resource waste.

Inventors

• YU HAI
• ZHANG MINGBO
• FANG MING
• GAO JIANGUO
• SONG HUIQIANG
• BAO QINGFENG
• XIN LI
• ZHANG ZIJIAN

Assignees

• 承德钒钛新材料有限公司
• 承德钢铁集团有限公司
• 河钢股份有限公司承德分公司

Dates

Publication Date

20260512

Application Date

20260107

Claims (8)

1. 1. An LF refining method for an unheated surplus recovery heat, comprising the steps of: And in the LF refining treatment process, adding a proper amount of 80 ferrovanadium smelting lean slag into a high-level feed bin for auxiliary slagging after adding a conventional slagging material, and obtaining qualified molten steel through subsequent LF refining desulfurization, temperature adjustment and fine adjustment.
2. 2. The LF refining method for an unheated surplus recovery heat according to claim 1, characterized in that the 80-ferrovanadium smelting lean slag single furnace is added in a total amount of 800-1100kg.
3. 3. An LF refining method for an unheated surplus recovery heat according to claim 1, characterized in that the maximum diameter of the 80 vanadium iron smelting lean slag after crushing is <10cm.
4. 4. The LF refining method for the unheated surplus recovery heat according to claim 1, wherein the 80-vanadium iron smelting lean slag comprises CaO% and SiO 2 %<3%、MgO%>10%、P%<1%、S%<1%、Al 2 O 3 % and 40% by mass.
5. 5. An LF refining method for an unheated residual recovery heat from a furnace according to claim 1, characterized in that the 80 vanadium iron smelting lean slag is added within 60 seconds after the addition of conventional slag forming material.
6. 6. The LF refining method for the unheated state casting and recycling heat is characterized in that 80 vanadium iron smelting lean slag is added twice, wherein 70% -80% of the total amount is added for the first time, and 20% -30% of the total amount is added for the second time.
7. 7. An LF refining method for an unheated residual recovery heat from a furnace according to claim 1, characterized in that the single batch addition of 80 ferrovanadium lean slag is not more than 70% of the single batch addition of conventional slag making material.
8. 8. The LF refining method for the non-thermal casting and recycling heat according to claim 1, wherein the end point components and the percentage content of the qualified molten steel are less than or equal to 0.05% C, less than or equal to 0.015% S, and the balance is iron and other unavoidable elements.

Description

LF refining method for non-thermal state casting surplus recovery heat Technical Field The invention belongs to the field of LF refining steelmaking, and particularly relates to an LF refining method for recovering heat without hot casting. Background The hot casting surplus generated by continuous casting cannot be recovered by 100% under the influence of factors such as production rhythm, matching degree of continuous casting pulling speed and converter tapping time, ladle hot repair treatment efficiency and the like. For the heat without hot casting recovery, a series of problems of large consumption of slag forming materials, low slag forming speed, long refining period and the like often occur in the LF refining process, and a modifier with higher cost is needed to be added as an auxiliary slag forming raw material, so that the slag forming cost is increased. The 80 ferrovanadium smelting lean slag is a byproduct in the production process of a vanadium plant, and is mostly used for marketing or consignment processing, so that resource waste and cost increase are caused. Disclosure of Invention The invention aims to provide an LF refining method for recycling the surplus heat of a non-thermal state, which utilizes 80 vanadium iron to smelt lean slag as an auxiliary raw material to improve LF refining slag forming efficiency, reduce slag forming material consumption, shorten refining period and save production cost. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: An LF refining method for an unheated surplus recovery heat, comprising the steps of: And in the LF refining treatment process, adding a proper amount of 80 ferrovanadium smelting lean slag into a high-level feed bin for auxiliary slagging after adding a conventional slagging material, and obtaining qualified molten steel through subsequent LF refining desulfurization, temperature adjustment and fine adjustment. Further, the total adding amount of the 80 vanadium iron smelting lean slag single furnace is 800-1100kg. Further, the maximum diameter of the broken 80-vanadium ferroalloy lean slag is less than 10cm. Further, the 80 vanadium iron smelting lean slag disclosed by the invention comprises the components of CaO% >5% and SiO 2%<3%、MgO%>10%、P%<1%、S%<1%、Al2O3% by mass. Further, the 80 vanadium iron smelting lean slag is added within 60 seconds after the conventional slag forming material is added. Further, the 80 vanadium iron smelting lean slag is added twice, wherein the total amount of the 80 vanadium iron smelting lean slag is 70-80% of the total amount of the first addition, and the total amount of the second addition is 20-30%. Further, the total addition amount of the 80 vanadium iron smelting lean slag in a single batch is not more than 70% of the total addition amount of the conventional slag making material in a single batch. Further, the end point component and the percentage content of the qualified molten steel are that C is less than or equal to 0.05 percent, S is less than or equal to 0.015 percent, and the balance is iron and other unavoidable elements. The technical scheme of the invention is as follows: The 80 ferrovanadium smelting lean slag can provide a large amount of Al 2O3,Al2O3 for slag, form a low-melting-point slag system with CaO and SiO 2 in the slag, and the low-melting-point slag system can improve the fluidity of the slag and inhibit the formation of high-melting-point and high-viscosity calcium silicate minerals. The high-fluidity slag can also provide favorable dynamic conditions for desulfurization, and the 80 vanadium iron smelting lean slag has more excellent effect of the modifier at low price, thereby achieving the purpose of reducing production cost. The beneficial effects of adopting above-mentioned technical scheme to produce lie in: The method effectively solves the problems of difficult slag formation, high slag formation cost and low desulfurization efficiency of the heat-state casting surplus recovery heat in the LF refining process, realizes the recovery and utilization of 80 ferrovanadium smelting lean slag, and reduces the resource waste. Detailed Description The present invention will be described in further detail with reference to examples. The method of the invention mainly aims at optimizing and controlling the adding proportion and the adding time of LF refining slag-making materials without hot casting and recycling heat, and the LF refining treatment is specifically as follows: (1) LF refining slag-making material adding proportion and adding time And conveying the crushed and dried 80-vanadium iron smelting lean slag to an LF refining high-level bin for standby through a feeding belt. The conventional slag making materials in the LF refining process are added in 2-3 batches according to the condition of molten steel, the slag making materials in the LF refining process mainly are small-particle lime, and an aluminum deoxidizer is selec