Method for recycling steel slag of LF (Low Frequency) furnace

A technology for furnace steel and steel slag, which is applied in the field of metallurgical industrial waste slag recycling, which can solve the problems of increasing the difficulty of desulfurization in the smelting process and reducing production efficiency, and achieves the effects of reducing energy consumption, reducing consumption, and simple process

Inactive Publication Date: 2011-10-05
NORTHEASTERN UNIV
View PDF2 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Continued use of these slags will inevitably increase the difficulty of

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for recycling steel slag of LF (Low Frequency) furnace

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] The LF steel slag obtained from the steel mill, after cooling, crushing, magnetic separation, and screening, chemical analysis shows that the composition is CaO 41%, Al 2 o 3 35%, MgO 10%, SiO 2 5%, S 0.8%, MnO+FeO 0.3%. In order to obtain the chemical composition CaO 42%, Al 2 o 3 36%, MgO 10%, SiO 2 5%, S<0.05%, MnO+FeO<0.5% pre-melted refining slag. After adding 3.5% limestone with a purity of 90% in an external way, heat the steel slag to 1300°C with air as the oxidizing gas and keep it warm for 2 hours to remove the sulfur in the slag to less than 0.05%, and then continue to heat up to make the slag composition uniform , the premelted refining slag whose composition fully meets the requirements can be obtained.

Embodiment 2

[0022] The LF steel slag obtained from the steel mill, after cooling, crushing, magnetic separation, and screening, chemical analysis shows that the composition is CaO 41%, Al 2 o 3 35%, MgO 12%, SiO 2 5%, S 0.8%, MnO+FeO 0.3%. To obtain the chemical composition CaO 41%, Al 2 o 3 35%, MgO 10%, SiO 2 6%, S<0.1%, MnO+FeO<0.5% pre-melted refining slag. After adding 50% lime containing 90% CaO and 5% magnesia containing 90% MgO and mixing them evenly, the steel slag is heated to 1250°C with air as the oxidizing gas and kept for 1 hour to remove the sulfur in the slag to less than 0.1%, and then continue to raise the temperature to make the composition of the slag uniform, and the premelted refining slag whose composition fully meets the requirements can be obtained.

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 relates to a method for recycling steel slag of an LF (Low Frequency) furnace. The technical scheme of the invention is as follow: the method comprises the following steps of: removing metallic iron contained in the steel slag through cooling, grinding, magnetic separation and screening processes by taking the steel slag of the LF furnace as raw materials; then mixing modifiers, i.e. sulfur-containing CaO-Al2O3-SiO2-MgO series LF steel slag, a right amount of lime, and the like, and then completely oxidizing sulfur contained in the CaO-Al2O3-SiO2-MgO series LF steel slag or oxidizing to a predetermined degree at certain temperature in an appropriate heating furnace to finally obtain premelting refining slag of the LF furnace, which has excellent property, so as to achieve the purpose of recycling the steel slag in an iron and steel industry. According to the method disclosed by the invention, the recycling of the LF steel slag is completely realized; the environmental problems caused by waste slag stacking are prevented; the consumption of the raw materials, i.e. the lime and the like, is reduced; heat in the production process of the premelting refining slag is effectively utilized; and energy consumption is reduced.

Description

technical field [0001] The invention relates to the recycling of metallurgical industry waste slag, in particular to a method for recycling LF furnace steel slag. Background technique [0002] LF refining furnace is the most widely used external refining equipment due to its advantages of simple equipment, low investment cost, flexible operation and good refining effect. Among them, refining slag is the technical means and necessary condition to realize the refining functions such as heat preservation, deoxidation, desulfurization and absorption of steel inclusions in LF furnace. For every 1 ton of molten steel refined, 20-50kg of refining slag needs to be consumed. According to my country's steel output of 626 million tons in 2010, if 1 / 2 of it uses the LF furnace refining process, at least 6.26 million tons of LF furnace steel slag will be produced. Therefore, the recycling of LF furnace steel slag is an important part of the development of circular economy in the iron an...

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
IPC IPC(8): C21C7/00C21B3/06
CPCY02W30/50
Inventor 戴文斌于景坤陈敏王新丽
Owner NORTHEASTERN UNIV
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