Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Finished pellet and preparation method thereof

A technology for pelletizing and finished products, which is applied in the field of finished pellets and its preparation, can solve the problems of high FeO content, high wet return rate, poor quality of green pellets, etc., to reduce FeO content, increase specific surface area, and improve uniformity sexual effect

Active Publication Date: 2021-02-05
SHOUGANG JINGTANG IRON & STEEL CO LTD
View PDF4 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Generally, the binder used in the production of acid pellets is bentonite, subject to the restriction of high reduction expansion rate, some companies can only use calcium-based bentonite, which can reduce the reduction expansion rate of pellets, but calcium The water absorption rate and other indicators of base bentonite are far lower than those of sodium base bentonite, so the quality of raw pellets is poor, the material layer of the roaster has poor air permeability, and the pellets are not fully roasted. , the number of drops is low, and the wet return rate is high, which restricts the increase of production capacity

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
  • Finished pellet and preparation method thereof
  • Finished pellet and preparation method thereof
  • Finished pellet and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0037] According to another typical embodiment of the present invention, a method for preparing finished pellets is provided, such as figure 1 shown, including:

[0038] S1, after mixing iron ore powder with slaked lime and calcium-based bentonite, a mixture is obtained;

[0039] S2. Putting the mixture into pellets to obtain raw pellets;

[0040] S3. Sieving the green balls to obtain sieved green balls;

[0041] S4. Roasting the sieved green pellets to obtain finished pellets.

[0042] By adding a small amount of slaked lime, the specific surface area of ​​the mixture can be increased, thereby improving the drop strength of the green balls and the uniformity of particle size. The improvement of the quality of the green pellets is beneficial to reduce the damage of the belt transportation and the powder entering the roasting machine, improve the circulation of the hot air flow in the material layer, and provide sufficient oxidizing atmosphere for the pellets during the roas...

Embodiment 1

[0053] Mix iron ore powder, calcium-based bentonite, and slaked lime in a mass ratio of 97:2.8:0.2 to form a mineral powder mixture, and then add an appropriate amount of water to mix evenly to adjust the water content of the mineral powder mixture to 8.0%. For example, 485 tons of iron ore powder, 14 tons of calcium-based bentonite, and 1 ton of slaked lime are added per hour to mix the ore powder mixture evenly.

[0054] The mineral powder mixture is pelletized in the disc pelletizer for 10 minutes. After the pelletizing is completed, the qualified balls with a particle size of 8-16mm are sieved with a roller screen and put into the roaster. material belt. The green balls with qualified particle size are roasted through a belt roaster: the green balls are first air-dried at a temperature of 320°C for 4 minutes, then air-dried at a temperature of 350°C for 4 minutes, and then dried at a temperature of 500°C-1000°C (according to a certain temperature gradient) Heating) Prehea...

Embodiment 2

[0056] Mix iron ore powder, calcium-based bentonite, and slaked lime in a mass ratio of 97:2.6:0.4 to form a mineral powder mixture, and then add an appropriate amount of water to mix evenly to adjust the water content of the mineral powder mixture to 8.5%. For example, 485 tons of iron ore powder, 13 tons of calcium-based bentonite, and 2 tons of slaked lime are added per hour to mix the ore powder mixture evenly.

[0057] The mineral powder mixture is pelletized in the disc pelletizer for 11 minutes. After the pelletizing is completed, the qualified balls with a particle size of 8-16mm are sieved with a roller screen and put into the roaster. The raw pellets smaller than 8mm and larger than 16mm are returned to the mix material belt. The green balls with qualified particle size are roasted through a belt roaster: the green balls are first air-dried at a temperature of 330°C for 5 minutes, then air-dried at a temperature of 360°C for 5 minutes, and then dried at a temperature...

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
water absorptionaaaaaaaaaa
Login to View More

Abstract

The invention discloses a finished pellet. The finished pellet comprises, by mass: 96.5%-98.4% of iron ore powder, 0.1%-0.5% of slaked lime and 1.5%-3% of calcium bentonite, and the mass fraction of Ca(OH)2 in the slaked lime is more than 88%. The invention also discloses a preparation method of the finished pellet. The preparation method comprises the steps of uniformly mixing the proportioned iron ore powder with the slaked lime and the calcium bentonite to obtain a mixture; and carrying out pelletizing, screening and roasting on the mixture to obtain the finished pellet. According to the finished pellet and the preparation method thereof, through adding the small amount of slaked lime, the specific surface area of the mixture can be improved, the falling strength and granularity uniformity of green pellets are further improved, and the quality of the green pellets is improved; the improvement of the quality of the green pellets is beneficial to the improvement of the circulation ofthe hot gas flow in a material layer, and sufficient oxidizing atmosphere is provided for the pellets in the roasting process, so that the content of FeO in the finished pellets is reduced; and the small amount of slaked lime plays a role of sulfur fixation, and the influence of the combination of sulfur and oxygen on the oxidation of ferrous iron is reduced.

Description

technical field [0001] The invention relates to the technical field of pellet preparation, in particular to a finished pellet and a preparation method thereof. Background technique [0002] Magnetite pellets are used as raw materials for blast furnace smelting, and their quality has an important impact on the blast furnace smelting process and economy. Jingtang Company 5500m 3 Large blast furnaces have high smelting intensity and require higher quality pellets. FeO content is one of the important quality indicators of pellets and has an important impact on blast furnace smelting. It is generally believed that every 1% decrease in the FeO content of the pellets corresponds to a 1% decrease in the coke ratio of the blast furnace. Reducing the FeO content is beneficial to the indirect reaction of the blast furnace and improves economic benefits. [0003] The pellet production process is a comprehensive process. There are many factors that affect the FeO content of the finish...

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): C22B1/243C22B1/02
CPCC22B1/243C22B1/2406C22B1/02
Inventor 王凯李建华耿朝阳刘文旺高宝奎李铮周志伟沈建庭郝建钊赵宏森张春猛康胜辉吴峰川孙宝家康海军青格勒
Owner SHOUGANG JINGTANG IRON & STEEL CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products