CN101270399A

CN101270399A - Method for producing metallic iron grain with iron containing waste slag dust

Info

Publication number: CN101270399A
Application number: CNA2008100475607A
Authority: CN
Inventors: 薛正良; 杨叠; 张海峰
Original assignee: Wuhan University of Science and Engineering WUSE
Current assignee: Wuhan University of Science and Engineering WUSE
Priority date: 2008-04-30
Filing date: 2008-04-30
Publication date: 2008-09-24

Abstract

The invention particularly relates to a production method of metal iron particles by utilizing the waste slag and dust of containing iron. The technical proposal is adopted as follows: firstly 55 to 75 weight percent of converter dust, 10 to 25 weight percent of blast furnace dust or pyrite cinder and 12 to 20 weight percent of coal powder are well-mixed; secondly the mixture is self-reduced about 10 to 15 minutes in a rotary hearth furnace under the condition of 1300 to 1380 DEG C after briquetting, palletizing and drying; finally the reduction product is discharged, carried out the separation of iron particle and dreg after water quenching. The metal contains more than 95 percent of iron, the iron yield reaches over 92 percent, the dimensions of metal iron particles mainly distribute between 5 to 35 milimeters, and more than 90 percent of sulfur and more than 20 percent of phosphorus in raw material can be removed. Therefore, the production method of metal iron particles by utilizing the waste slag and dust of containing iron has the advantages of the simple process, the low requirement on quality of raw material, the low energy consumption, the low production cost, the high iron yield, and removing part of sulfur and phosphorus in raw material.

Description

A kind of method with producing metallic iron grain with iron containing waste slag dust

Technical field

The invention belongs to metal abrasive grit production technical field.Be specifically related to a kind of method with producing metallic iron grain with iron containing waste slag dust.

Background technology

As far back as the seventies in 20th century, international metal recovery company (Inmetco) has invented with valuable element Ni and Cr in the carbonaceous pelletizing direct-reduction process recovery stainless steel plant secondary dust, be called Inmetco method (PargeterJ K, MacDongall J A.Ironmaking Using the Inmetco Process and RelatedTechnologies, 44 ^ThIronmaking Proceeding Conferenec.Detroit, ISS USA, 1985:275～285).U.S. Midrex company is applied to this method the direct reduction of powdered iron ore carbonaceous pelletizing, be used to produce direct-reduced iron, and this method called Fastmet method (Winston L.Tennies, JamesA.Lepinski, John T.Kopfle.The Midrex Fastmet Process a Simple, EconomicIronmaking Option, MPT.1991,14 (2): 36～42).These two kinds of technologies are reduction apparatus with annular rotary hearth furnace all, and the product that obtains all is the sponge iron that slag iron is regardless of.The third generation ironmaking technology (ITmk3) of Japan Kobe Iron And Steel Company invention is with interior coal blending pelletizing quick autoreduction under 1400～1450 ℃ of high temperature in rotary hearth furnace, can directly obtain and the isolating iron particle of bits, but this method can't be handled low-grade iron ore and iron slag and dust (I.Kobayashi et al..A new process to produced iron directly fromfine ore and coal, I﹠amp; M, Sept.2001:19～22).

Summary of the invention

The purpose of this invention is to provide a kind of technology simple, to raw materials quality require low, energy consumption is low, production cost is low, the recovery rate height of iron, can remove the sulphur in the raw material, the method with producing metallic iron grain with iron containing waste slag dust of phosphorus.

For achieving the above object, the technical solution adopted in the present invention is: earlier be that 55～75% converter stove dirt, 10～25% blast furnace dust or sulfate slag, 12～20% coal dust are that raw material carries out mixing with the quality percentage composition; Again through briquetting or after making ball, drying, under 1300～1380 ℃ condition, autoreduction 10～15min in rotary hearth furnace; Then reduzate is drawn off, after shrend, carry out separating of abrasive grit and bits, promptly produce the metal abrasive grit.

The technical program to the requirement of raw material is:

Converter stove dirt: TFe 〉=55wt%, granularity＜1mm;

Blast furnace dust: TFe 〉=50wt%, granularity＜1mm;

Sulfate slag: TFe 〉=48wt%, granularity＜1mm;

Coal dust: fixed carbon 〉=75wt%, volatile matter≤10wt%, granularity＜0.1mm.

Owing to adopting technique scheme, the present invention produces iron granule with joining carbon agglomerate high temperature autoreduction in converter stove dirt and blast furnace dust or the sulfate slag composition, has the advantages that technology is simple, low to the raw materials quality requirement, energy consumption is low, production cost is low; The iron particle size of being produced mainly is distributed between 5～35mm, and the recovery rate of iron reaches more than 92%, and can remove sulphur more than 90% and 20% above phosphorus in the raw material.

Embodiment

Only the invention will be further described below in conjunction with embodiment, rather than limiting the scope of the invention.

Embodiment 1

A kind of method with producing metallic iron grain with iron containing waste slag dust: with converter stove dirt, blast furnace dust is powder-material, and reductive agent is a coal dust; Be that raw material carries out mixing with the converter stove dirt of 65～75wt%, the blast furnace dust of 10～20wt%, the coal dust of 12～15wt% earlier; Again after briquetting, drying, adopt producer gas to do fuel, under 1300～1350 ℃ condition in rotary hearth furnace autoreduction 10～15min; Then reduzate is drawn off back quenching in water, the metal abrasive grit is separated with bits by magnet.Separating obtained product is the metal abrasive grit of containing metal iron 〉=95%, and the iron particle size mainly is distributed between 5～35mm.

The requirement of 1 pair of raw material of present embodiment is:

Converter stove dirt: TFe 〉=55wt%, granularity＜1mm;

Blast furnace dust: TFe 〉=50wt%, granularity＜1mm;

Embodiment 2

A kind of method with producing metallic iron grain with iron containing waste slag dust: with converter stove dirt, sulfate slag is powder-material, and reductive agent is a coal dust, is that raw material carries out mixing with the converter stove dirt of 65～75wt%, the sulfate slag of 10～18wt%, the coal dust of 15～18wt% earlier; Again after briquetting, drying, adopt natural gas to do fuel, under 1350～1380 ℃ condition in rotary hearth furnace autoreduction 10～15min; Then reduzate is drawn off the back in water quenching, by magnet the metal abrasive grit is separated with bits.Separating obtained product is the metal abrasive grit of containing metal iron 〉=95%, and the iron particle size mainly is distributed between 5～35mm.

The requirement of 2 pairs of raw materials of present embodiment is:

Converter stove dirt: TFe 〉=58wt%, granularity＜1mm;

Sulfate slag: TFe 〉=48wt%, granularity＜1mm;

Embodiment 3

A kind of method with producing metallic iron grain with iron containing waste slag dust: with converter stove dirt, blast furnace dust is powder-material, reductive agent is a coal dust, is that raw material carries out mixing with the converter stove dirt of 55～65wt%, the blast furnace dust of 20～25wt%, the coal dust of 15～20wt% earlier; Again after making ball, drying, adopt producer gas to do fuel, under 1300～1350 ℃ condition in rotary hearth furnace autoreduction 10～15min; Then reduzate is drawn off back quenching in water, the metal abrasive grit is separated with bits by magnet.Separating obtained product is the metal abrasive grit of containing metal iron 〉=95%, and the iron particle size mainly is distributed between 5～35mm.

The requirement of 3 pairs of raw materials of present embodiment is:

Converter stove dirt: TFe 〉=55wt%, granularity＜0.1mm;

Blast furnace dust: TFe 〉=50wt%, granularity＜0.1mm;

This embodiment is produced iron granule with joining carbon agglomerate high temperature autoreduction in converter stove dirt and blast furnace dust or the sulfate slag composition, has the advantages that technology is simple, low to the raw materials quality requirement, energy consumption is low, production cost is low; The iron particle size of being produced mainly is distributed between 5～35mm, and the recovery rate of iron can reach more than 95%, can remove sulphur more than 90% and 20% above phosphorus in the raw material.

Claims

1, a kind of method with producing metallic iron grain with iron containing waste slag dust is characterized in that being earlier 55～75% converter stove dirt, 10～25% blast furnace dust or sulfate slag, 12～20% coal blending with the quality percentage composition; Again through briquetting or after making ball, drying, under 1300～1380 ℃ condition, autoreduction 10～15min in rotary hearth furnace; Then reduzate is drawn off, after shrend, carry out separating of abrasive grit and bits.

2, the method for producing metallic iron grain with iron containing waste slag dust according to claim 1 is characterized in that:

Converter stove dirt: TFe 〉=55wt%, granularity＜1mm;

Blast furnace dust: TFe 〉=50wt%, granularity＜1mm;

Sulfate slag: TFe 〉=48wt%, granularity＜1mm;