Method for preparing direct reduced iron from low-grade high-phosphorus high-silicon iron ore

A technology for reducing iron and lean iron ore, which is applied in furnaces, furnace types, fluidized bed furnaces, etc., can solve the problems of complex embedded particle size, unreported and applied, high phosphorus content, etc., achieving remarkable technical and economic effects, The effect of solving the contradiction between supply and demand of iron ore resources and high iron recovery rate

Inactive Publication Date: 2010-10-20
KUNMING IRON & STEEL HLDG CO LTD
View PDF1 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, for the difficult-to-separate low-grade ores with complex components, extremely fine embedded particle size, and high phosphorus content, it is impossible to separate them with the above-mentioned prior art.
Many domestic units have conducted various studies on low-grade refractory iron ore, and the final products are mostly metallized agglomerates, in which elements such as sulfur (S) and phosphorus (P) have not decreased much; in addition, some units have been in In the laboratory, chemical agents are used to dephosphorize it, but it is only limited to the laboratory stage, and there are no follow-up reports and applications

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 preparing direct reduced iron from low-grade high-phosphorus high-silicon iron ore
  • Method for preparing direct reduced iron from low-grade high-phosphorus high-silicon iron ore

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] The composition of the raw iron ore used is: TFe: 47.24%, P: 0.907%, SiO 2 : 16.78%.

[0020] Go through the following steps:

[0021] 1. After the above raw ore is crushed by conventional crushing equipment until the particle size is less than 15mm, dephosphorize the crushed ore with coal powder reducing agent and sodium carbonate according to the mass ratio of ore: reducing agent: dephosphorizing agent = 100:30:25 When the RQ-35-2 rotary kiln is heated to 1000°C, add it into the rotary kiln, and roast it for 18 hours at this temperature and the rotary kiln speed is 3r / min to obtain loose primary direct reduced iron. ;

[0022] 2. Make the loose primary direct reduced iron in step 1 into pulp with a mass concentration of 67%, send it to a conventional grinding machine for grinding for 3 minutes, and the grinding fineness is: -0.074mm (200 mesh) accounting for 70%; Coarse magnetic separation is carried out under the condition of a magnetic field strength of 110kA / m (...

Embodiment 2

[0025] The original ore composition of the oxide ore used is: TFe: 45.62%, P: 0.91%, SiO 2 : 16.78%.

[0026] Go through the following steps:

[0027] 1. After the above raw ore is crushed by conventional crushing equipment until the particle size is less than 15mm, dephosphorize the crushed ore with lignite powder reducing agent and sodium sulfate according to the mass ratio of ore: reducing agent: dephosphorizing agent = 100:45:50 Mix the agent evenly, pack it in tanks, put it into a tunnel kiln with a size of 2.6×3.0×120 meters, and roast it for 50 hours at a temperature of 1150°C, and the high-temperature reduction time is 24 hours to obtain roasted ore, roasted ore The composition is: TFe: 40.23%, P: 0.76%, SiO 2 : 18.52%, MFe: 36.56%;

[0028] 2. Prepare the roasted ore from step 1 into a slurry with a mass concentration of 50%, grind it in a conventional ball mill for 20 minutes, and magnetically separate it in a conventional magnetic separator with a magnetic field ...

Embodiment 3

[0031] The raw ore composition of the oxide ore used is: TFe: 47.24%, P: 0.907%, SiO 2 : 16.78%.

[0032] Go through the following steps:

[0033] 1. After the above raw ore is crushed by conventional crushing equipment until the particle size is less than 15mm, dephosphorize the crushed ore with coke powder reducing agent and calcium bicarbonate according to the mass ratio of ore: reducing agent: dephosphorizing agent = 100:38:30 The phosphorus agent is mixed evenly, packed in tanks, put into a tunnel kiln with a size of 2.2×2.6×100 meters, and roasted for 50 hours at a temperature of 1200°C, and the high-temperature reduction time is 20 hours to obtain roasted ore. The composition is: TFe: 31.75%, P: 0.74%, SiO 2 : 19.82%, MFe: 25.78%;

[0034] 2. Make the roasted ore in step 1 into pulp with a mass concentration of 50%, grind it with a conventional baseball mill for 10 minutes, and magnetically separate it with a conventional drum magnetic separator with a magnetic field...

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 method for preparing direct reduced iron from low-grade high-phosphorus high-silicon iron ore. The method comprises the following steps of: uniformly mixing the low-grade high-phosphorus high-silicon refractory iron ore serving as a raw material, a reducing agent and a dephosphorizing agent in a mass ratio of 100:30-45:25-50, reducing and roasting the mixture for 18 to 24 hours; separating impurities such as phosphorus, SiO2 and the like from the ore by conventional grinding and magnetic separation; briquetting direct reduced iron powder obtained by magnetic separation, and feeding briquette serving as a steel-making raw material instead of steel scrap into a steel-making furnace, so that the low-grade high-phosphorus high-silicon iron ore with complex mineral composition, various tightly symbiotic minerals and low disseminated grain size is comprehensively utilized. The method has the advantages of small investment and simple process by saving equipment and processes with high energy consumption and heavy pollution such as ore dressing, sintering, palletizing, coking and the like, no waste discharge, no environmental pollution, high recovery rate of the iron from the ore, and remarkable phosphorus and silicon removing effect by comprehensively utilizing phosphorus-containing and silicon-containing gangue and recovering valuable elements therein.

Description

technical field [0001] The present invention relates to a production method of direct reduced iron, especially a method for reducing, roasting and magnetically separating low-grade, high-phosphorus, high-silicon, and poor iron ore, simultaneously dephosphorizing and desiliconizing, and obtaining direct reduced iron, which belongs to ore separation Metallurgical combined technical field. Background technique [0002] Due to the development of the world economy, the demand for mineral resources in various countries is increasing day by day. However, resource minerals are showing a decreasing trend, and the price of ore is rising year by year. Among my country's proven iron ore resources, low-grade and difficult-to-smelt iron ores are widely distributed and have large reserves of about 10 billion tons, which have great potential for development. Due to the complex mineral composition of this kind of mineral resources, and the close symbiosis of various minerals, the embedded ...

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): C21B13/00
Inventor 张竹明王化军罗明发叶亚雄孙体昌栗伟雷云唐美锡官金莲
Owner KUNMING IRON & STEEL HLDG 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

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