Dephosphorization method of converter oxygen tapping

A converter and dephosphorization technology, applied in the metallurgical field, can solve the problems of large temperature drop of dephosphorization hot metal, increased steelmaking cost, small reaction interface, etc., and achieves the effect of improving dephosphorization efficiency, low cost and improving dephosphorization effect.

Active Publication Date: 2016-11-16
TANGSHAN STAINLESS STEEL +1
View PDF4 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The temperature drop of dephosphorized molten iron in ladle or torpedo tank is large, the reaction interface is small, the ratio of scrap steel is low (≤5%), and equipment investment is required; the dual process of two converters requires redundant converters for dephosphorization; increase the alkalinity And reduce the tapping temperature to increase the cost of steelmaking

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] The dephosphorization of the converter ladle adopts the following specific process steps.

[0036] 100 tons of converter conventional smelting; converter end point [C] 0.035%, [O] 650ppm, [P] content 0.015%, molten iron temperature [T] 1705 ℃. The weight ratio of the slag components at the end of the converter: CaO 55%, MgO 12%, SiO 2 17%, Al 2 o 3 1%, FeO 15%.

[0037] The converter is tapped with oxygen. When tapping 30%, add lime 2kg / ton steel, fluorite 0.2kg / ton steel, and add modifier 0.8kg / ton steel after tapping. After the steel tapping is completed, the strong stirring gas volume is 12L / min, and the ladle is dephosphorized by stirring for 3 minutes; the mass composition of the modifier is: CaO 20%, MgO 5%, SiO 2 5%, Al 2 o 3 20%, Al 50%.

[0038] The composition of ladle slag after tapping is 40% CaO, 6% MgO, SiO 2 12%, Al 2 o 3 37%, FeO 5%.

[0039] After the ladle is dephosphorized, the [P] content is reduced from 0.015% to 0.011%.

Embodiment 2

[0041] The method for suppressing slag in the converter adopts the following specific process steps.

[0042] 100 tons of converter conventional smelting; converter end point [C] 0.035%, [O] 600ppm, [P] content 0.015%, molten iron temperature [T] 1685 ℃. The weight ratio of the slag components at the end of the converter: CaO 51%, MgO 8%, SiO 2 17%, Al 2 o 3 3%, FeO 21%.

[0043] The converter is tapped with oxygen. When tapping 50%, add lime 4kg / ton steel, fluorite 0.4kg / ton steel, add modifier 0.8kg / ton steel after tapping, strong stirring gas volume 10L / min after tapping, Stir for 3 minutes for ladle dephosphorization. The mass composition of the modifier is: CaO 30%, MgO 2%, SiO 2 3%, Al 2 o 3 20%, Al 45%.

[0044] The composition of ladle slag after tapping is 30% CaO, 12% MgO, SiO 2 7%, Al 2 o 3 40%, FeO 11%.

[0045] After the ladle is dephosphorized, the [P] content is reduced from 0.015% to 0.009%.

Embodiment 3

[0047] The method for suppressing slag in the converter adopts the following specific process steps.

[0048] Conventional smelting in a 100-ton converter; converter endpoint [C] 0.035%, [O] 600ppm, [P] content 0.013%, molten iron temperature [T] 1685°C. The weight ratio of the slag components at the end of the converter: CaO 45%, MgO 12%, SiO 2 17%, Al 2 o 3 5%, FeO 21%.

[0049] When tapping 30% of the steel, add lime 4kg / ton steel, fluorite 0.4kg / ton steel, add 1.2kg / ton steel modifying agent when tapping 80%, strong stirring gas volume 8L / min after tapping , stirring for 3 minutes for ladle dephosphorization. The mass composition of the modifier is: CaO 25%, MgO 3%, SiO 2 2%, Al 2 o 3 20%, Al 50%.

[0050] The composition of ladle slag after tapping is 40% CaO, 10% MgO, SiO 2 6%, Al 2 o 3 35%, FeO 9%.

[0051] After the ladle is dephosphorized, the [P] content is reduced from 0.013% to 0.009%.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a dephosphorization method of converter oxygen tapping. The method is characterized in that after converter smelting is finished, oxygen tapping is carried out, in the tapping process, lime, fluorite and a modifier are added, and after tapping is finished, steel ladle dephosphorization is carried out through stirring. On the premise that the technology path is not changed, the dephosphorization capacity of steel ladle slag is utilized fully, the dephosphorization efficiency of a production line is improved by 2% to 4%, the dephosphorization effect of the converter-RH technology is stably improved, the converter dephosphorization pressure is reduced, the component judgment drop caused by phosphorus content standard exceeding of a steel ladle is avoided, the cost is low, and the efficiency is high.

Description

technical field [0001] The invention relates to a converter dephosphorization method, in particular to a converter dephosphorization method for tapping steel with oxygen, and belongs to the technical field of metallurgy. Background technique [0002] As the market demand for high-grade high-quality steel increases, low-phosphorus steel and ultra-low-phosphorus steel, as an indispensable part of the pure steel production process, have received more and more attention. Adopting new technologies and processes to reduce phosphorus in steel as much as possible Content has become the main research direction of many iron and steel enterprises. [0003] The phosphorus content of domestic blast furnace hot metal is concentrated between 0.120% and 0.130%. Steel types such as IF steel require the tapping temperature to be higher than 1670°C, and the phosphorus content of the finished product is less than 0.012% or even 0.010%. Dephosphorization efficiency requires >90% or even high...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C21C7/064
CPCC21C7/0645
Inventor 周泉林李阳李朋王肖周航邢金栋刘海波赵铁成李杨尹宽张红娟
Owner TANGSHAN STAINLESS STEEL
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products