Detoxification method of chromium-containing slag entering metallurgical blast furnace by using coal spraying process form

A technology for harmless treatment and chromium slag, applied in the fields of iron and steel metallurgy and environmental protection, can solve the problems of falling molten iron production, secondary pollution, difficult popularization and application, etc., and achieve the effect of full recycling and less links.

Active Publication Date: 2010-07-14
CHONGQING ANGRUIYUE SCI & TECH
View PDF0 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Although there are many existing methods, either the detoxification is incomplete, easy to cause secondary pollution, or the cost is too high
[0003] Chinese patent literature discloses a "method for realizing the harmless recycling of chromium slag by blast furnace ironmaking process" (2007100569402). , the disadvantage of this method is that when the chromium slag is made into self-fluxing agglomeration, it is easy to cause secondary pollution
The disadvantage of this treatment process is that the chromium slag and adhesive are extruded into a block and directly enter the blast furnace. Its thermal strength technical index is difficult to meet the requirements of blast furnace smelting. The thermal strength technical index is poor, which will cause poor air permeability of the blast furnace material column. , a series of problems such as the increase of the coke ratio and the decrease of the output of molten iron, it is difficult to popularize and apply it in the metallurgical industry at present
At the same time, this technology is not guaranteed by reliable sealing and dust-free technology, which is easy to cause secondary pollution

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
  • Detoxification method of chromium-containing slag entering metallurgical blast furnace by using coal spraying process form
  • Detoxification method of chromium-containing slag entering metallurgical blast furnace by using coal spraying process form

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] 1. Raw material treatment: prepare the chromium slag in the slag yard of the chromium slag production plant, including drying and grinding. The moisture content of the chromium slag drying is less than 1-10%, and the required particle size for grinding is -200 mesh 20-80 %.

[0020] 2. Transport the dried and ground chromium slag to the coal injection system of the blast furnace with a sealed tank car, and then send it into the sealed bin of the blast furnace by pneumatic means, and then mix it into the coal mill in the coal injection system by the feeder according to the set metering Inside, in the coal mill 6, the chromium slag and coal powder are fully ground and mixed, and sent into the coal powder bin with dry compressed air, and then enter the mixer through the injection tank, and then the mixed Chromium slag and coal powder are sprayed into the hearth of the blast furnace through the spray gun 27 via compressed air; the proportion of chromium slag mixed into the ...

Embodiment 2

[0025] 1. Raw material treatment: Dry the chromium slag to make the water content less than 4%, and grind it finely to make the particle size -200 mesh more than 70%;

[0026] 2. Transport the dried and finely ground chromium slag to the coal injection system of the blast furnace with a sealed tank car, and send it to the sealed bin of the blast furnace by means of a pneumatic pump through a sealed pipeline, and then mix it into the coal injection system according to the set metering by the feeder In the coal mill in the system, in the coal mill 6, the chromium slag and coal powder are fully ground and mixed, and then sent into the coal powder bin with dry compressed air, and then enter the mixer through the injection tank , and then the mixed chromium slag and coal powder are sprayed into the hearth of the blast furnace through the spray gun 27 via compressed air; wherein the ratio of chromium slag mixed into the coal powder is 5% of the weight of the coal powder.

[0027] 3....

Embodiment 3

[0031] 1. Raw material treatment: Dry the chromium slag to make the water content less than 5%, and grind it finely to make the particle size -200 mesh more than 60%;

[0032] 2. The dried and ground chromium slag is transported to the coal injection system of the blast furnace by a sealed tank car, sent to the sealed bin of the blast furnace through a sealed pipeline by a pump, and then mixed into the grinding chamber in the coal injection system by the feeder according to the set metering. In the coal machine, in the coal mill 6, the chromium slag and coal powder are fully ground and mixed, and then sent into the coal powder bin with dry compressed air, and then enter the mixer through the injection tank, and then the mixed Uniform chromium slag and coal powder are sprayed into the hearth of the blast furnace through the spray gun 27 via compressed air; wherein the ratio of chromium slag mixed into the coal powder is 10% of the weight of the coal powder.

[0033] 3. Spray th...

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 provides a detoxification method of chromium-containing slag entering metallurgical blast furnace by using coal spraying process form. The method comprises the following steps: first drying and grinding the chromium-containing slag, then uniformly blending chromium-containing slag in an amount of 1 to 15 percent of the weight of coal powder into the coal powder, spraying the coal powder blended with the chromium-containing slag into a blast furnace cylinder from a blast furnace coal-spraying system, detoxifying the hexavalent chromium in the chromium-containing slag at the high temperature of the blast furnace under the reducing atmosphere, reducing the hexavalent chromium into trivalent chromium, and finally reducing the trivalent chromium into a chromium metal, wherein 92 to 98 percent of the chromium metal is melted into molten iron and 2 to 8 percent of the chromium metal enters the furnace slag; and meanwhile, reducing the iron oxide in the chromium-containing slag into iron metal for entering the molten iron. By utilizing the sealed blast furnace coal-spraying system to directly spray the chromium-containing slag into the blast furnace cylinder, the method has the advantages of few links, no pollution, thorough detoxification due to direct and full utilization of the high-temperature reducing atmosphere, full recycling and lowest cost compared with that of the conventional methods for treating chromium-containing slag.

Description

technical field [0001] The invention belongs to the technical fields of iron and steel metallurgy and environmental protection. Background technique [0002] At present, there are four methods for the harmless treatment of chromium slag: chemical method, physical / chemical method, melting method and solidification / stabilization method, among which the melting method is the most thorough. The melting method is a process of detoxifying hexavalent chromium by adding additives to toxic substances at high temperature. The smelting and harmless treatment technologies of chromium slag mainly include carbon reduction method, sintering method, dry reduction method and cyclone furnace sintering method. Although there are many existing methods, either the detoxification is incomplete, easily causing secondary pollution, or the cost is too high. [0003] Chinese patent literature discloses a "method for realizing the harmless recycling of chromium slag by blast furnace ironmaking proce...

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): C21B5/00A62D3/37A62D101/43
CPCY02P10/20
Inventor 李秉正邓勇
Owner CHONGQING ANGRUIYUE SCI & TECH
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