Method for manufacturing additives and method for refining molten steel using the same

An additive preparation and additive technology, which is applied in the field of additive preparation and molten iron refining, can solve the problems of sulfur increase and high content, and achieve the effects of improving dephosphorization rate and desulfurization rate, improving refining rate, and reducing sludge landfill

Inactive Publication Date: 2019-07-09
POHANG IRON & STEEL CO LTD
View PDF6 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the high content of sulfur (S) contained in the sludge, there has been a problem of increasing sulfur (S) in molten iron

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 manufacturing additives and method for refining molten steel using the same
  • Method for manufacturing additives and method for refining molten steel using the same
  • Method for manufacturing additives and method for refining molten steel using the same

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0037] The invention relates to an additive preparation method for reusing sludge generated in a steelmaking process. More specifically, the present invention provides a method for preparing an additive. The additive is prepared by reusing steelmaking sludge. Adding the additive during refining can prevent the increase of sulfur (S) in molten iron, and is harmful to the environment. friendly.

[0038] figure 1 is a flowchart illustrating an additive preparation method according to an embodiment of the present invention. figure 2 is a block diagram showing an additive preparation apparatus according to an embodiment of the present invention. image 3 is a block diagram showing an additive preparation apparatus according to a first modification of the embodiment. Figure 4 is a block diagram showing an additive preparation apparatus according to a second modification of the embodiment.

[0039] The additive preparation method according to the embodiment of the present inven...

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 manufacturing additives and a method for refining molten steel using the same. The method for manufacturing the additives according to embodiment includes a stepof recovering sulfuric acid (H2SO4) after a pickling process of a steel plate; a step of recovering an acid mixture containing hydrofluoric acid (HF) and nitric acid (HNO3) after a pickling process ofa steel plate. A step of preparing a first additive includes a step of neutralizing the sulfuric acid. A step of preparing a second additive includes a step of neutralizing the acid mixture besides the sulfuric acid. According to embodiments, sludge prepared from the waste acid mixture is free of S (sulfur) and can be used for manufacturing any one of a slag former, a dephosphorization agent anda desulfurizing agent during refining in a steelmaking process, namely, even if sludge prepared by reutilization of waste acid is utilized as an additive, sulfur (S) in molten iron will not increase.

Description

technical field [0001] The invention relates to a method for preparing an additive and a method for refining molten iron using the method. More specifically, the present invention relates to a method for preparing an additive capable of reusing steelmaking sludge and a method for refining molten iron using the method. Background technique [0002] The production of steel, especially stainless steel, involves annealing and pickling processes. Annealing is a heat treatment operation to recrystallize the microstructure of steel and improve ductility. After annealing, an oxide layer forms on the surface of the steel, and directly below this oxide layer a chromium-depleted layer forms. The oxide layer and the chromium-depleted layer thus formed are removed by a subsequent operation descaling process. [0003] The descaling process to remove oxide and chromium-depleted layers is a pickling process used to remove unwanted metal deposits on the steel surface after annealing. Gen...

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): C21C1/02C21C7/064C21C7/076
CPCC21C1/025C21C7/0645C21C7/076Y02P10/20C23G1/36
Inventor 金完伊南在祐宋浚旻
Owner POHANG IRON & STEEL CO LTD
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