A method of slagging with raw dolomite and magnesium in converter reblowing

A raw dolomite and converter technology, applied in the direction of manufacturing converters, etc., can solve the problems that the determination of the substitution amount is difficult to control, the speed of slag formation is affected, and the heat of the converter is insufficient, so as to stabilize the converter process operation, save energy, and feed materials. Manage simple effects

Inactive Publication Date: 2015-11-18
武汉钢铁有限公司
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] It is believed that adding raw dolomite directly to converter slagging will have two problems: one is that raw dolomite needs to be decomposed first and then participate in the reaction, which affects the speed of slagging; the other is that the decomposition reaction absorbs heat and has a high cooling effect , it will cause insufficient heat in the converter, which is not conducive to slag melting, and it is easy to cause splashing
[0005] At present, limestone is used instead of active lime to make slag, but the total amount of active lime added to a furnace of steel in the normal process usually reaches 40-60kg / t. If limestone is used instead of active lime, the amount added will increase, which is easy to cause splashing. The limestone part is used Substituting active lime, the determination of the replacement amount and the difficulty in controlling the temperature

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

[0026] Implementation conditions of this example: 200t converter, molten iron temperature 1300°C, molten iron silicon content 0.3%; according to the type of steel implemented, the tapping temperature is set at 1660°C, after calculation including scrap steel, the molten steel temperature can reach 1690°C , the temperature margin is 30°C; the content of MgO in the slag is required to be 7%, and the single slag method is used for smelting.

[0027] This embodiment uses raw dolomite to join the method for magnesium slagging, its steps:

[0028] 1) During the dephosphorization and desiliconization of 200-ton converter reblowing, add raw dolomite with a particle size of 5-20mm according to 20kg / ton of steel to meet the requirements of magnesium;

[0029] Since the single slag method is adopted, 20kg / ton of steel raw dolomite is added at one time; scrap steel is added at 140kg / ton of steel; since the temperature of molten steel is 30°C richer than the set temperature of tapping, it i...

Embodiment 2

[0033] Implementation conditions of this example: 250t converter, molten iron temperature 1305°C, molten iron silicon content 0.35%; according to the type of steel implemented, the tapping temperature is set at 1670°C, after calculation including scrap steel, the molten steel temperature can reach 1680°C , the temperature margin is 10°C; the content of MgO in the slag is required to be 6%, and the double slag method is used for smelting.

[0034] This embodiment uses raw dolomite to join the method for magnesium slagging, its steps:

[0035] 1) During dephosphorization and desiliconization of 250-ton converter reblowing, add raw dolomite with a particle size of 5-20mm and 29kg / ton of steel;

[0036] Since the double slag method is adopted, the raw dolomite is added in two times: at the same time as the re-blowing and opening blowing, 70% of the weight of the raw dolomite should be added according to the ton of steel, that is, 20.6kg / ton of steel is added. At the same time of ...

Embodiment 3

[0042] Implementation conditions of this example: 250t converter, molten iron temperature 1305°C, molten iron silicon content 0.3%; according to the type of steel to be implemented, the tapping temperature is set at 1675°C, after calculation including scrap steel, the molten steel temperature can reach 1666°C , the temperature is 9°C lower; the content of MgO in the slag is required to be 7%, and the single slag method is used for smelting.

[0043] This embodiment uses raw dolomite to join the method for magnesium slagging, its steps:

[0044] 1) During the dephosphorization and desiliconization period of the 250-ton converter reblowing, add raw dolomite with a particle size of 5~20mm and 31kg / ton of steel; according to the principle that the added raw dolomite should not exceed 30kg / ton of steel, Therefore, the excess part is converted into light-burned briquettes to meet the requirement that the Mg content in the slag is 7%;

[0045] Since the single slag method is adopted...

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

PropertyMeasurementUnit
particle sizeaaaaaaaaaa
Login to view more

Abstract

The invention discloses a magnesium-matched slag-making method using raw dolomite in converter combined blowing. The method comprises the following steps: adding raw dolomite with the particle size of 5-20mm according to 10-30kg / ton of steel during phosphorus and silicon removal of converter combined blowing; completely adding the raw dolomite at one time when a single slag process is adopted; adding the raw dolomite for two times when a double slag process is adopted; adding steel scrap according to 135-150kg / ton of steel; performing a follow-up process according to the regular procedure. According to the invention, the raw dolomite is directly added for making slag at the earlier stage of performing oxygen top-bottom combined blowing during converter smelting, so that the energy consumption of the process can be reduced, the problem that splash is caused by plenty of added cooling agents under the condition that the converter steel-making temperature is in surplus can be effectively controlled; moreover, the amount of steel scrap can be reduced, and the production cost is reduced.

Description

technical field [0001] The invention relates to a method for making slag in molten steel smelting, in particular to a method for making slag by mixing raw dolomite with magnesium in reblowing of a converter. Background technique [0002] Oxygen top-bottom combined blowing converter is a process of forced oxygen supply, removal of impurity elements through oxidation reaction, and heat release of oxidation reaction to increase the temperature of molten steel. Dolomite, magnesium agent, etc. are used for slagging operation. Generally, converters use light-burned dolomite as the main raw material for slagging. Raw dolomite is the raw material for producing light-burned dolomite for converters. It is mainly composed of calcium-magnesium carbonate rocks, and its decomposition reaction is nCaMg(CO 3 ) 2 =MgO+nCaO+(n+1)CO 2 , Light-burned dolomite is obtained by calcining and decomposing raw dolomite at nearly 1000 ° C. Light-burned dolomite has high porosity and chemical activit...

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 Patents(China)
IPC IPC(8): C21C5/36
Inventor 杨文军李海洋彭琦宋泽啓孔勇江沈武邓品团崔辉彭长波林利平卢凯
Owner 武汉钢铁有限公司
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap