WO2021106008A1 - Réacteur à contre-courant - Google Patents

Réacteur à contre-courant Download PDF

Info

Publication number
WO2021106008A1
WO2021106008A1 PCT/IN2020/050517 IN2020050517W WO2021106008A1 WO 2021106008 A1 WO2021106008 A1 WO 2021106008A1 IN 2020050517 W IN2020050517 W IN 2020050517W WO 2021106008 A1 WO2021106008 A1 WO 2021106008A1
Authority
WO
WIPO (PCT)
Prior art keywords
reactor
rotary kiln
powder
input
countercurrent
Prior art date
Application number
PCT/IN2020/050517
Other languages
English (en)
Inventor
Narendra DHOKEY
Sameer Shinde
Original Assignee
Dhokey Narendra
Sameer Shinde
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dhokey Narendra, Sameer Shinde filed Critical Dhokey Narendra
Publication of WO2021106008A1 publication Critical patent/WO2021106008A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B7/00—Rotary-drum furnaces, i.e. horizontal or slightly inclined
    • F27B7/12—Rotary-drum furnaces, i.e. horizontal or slightly inclined tiltable
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F3/00—Manufacture of workpieces or articles from metallic powder characterised by the manner of compacting or sintering; Apparatus specially adapted therefor ; Presses and furnaces
    • B22F3/003—Apparatus, e.g. furnaces
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F9/00—Making metallic powder or suspensions thereof
    • B22F9/16—Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
    • B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B7/00—Rotary-drum furnaces, i.e. horizontal or slightly inclined
    • F27B7/02—Rotary-drum furnaces, i.e. horizontal or slightly inclined of multiple-chamber or multiple-drum type
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F27—FURNACES; KILNS; OVENS; RETORTS
    • F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
    • F27B7/00—Rotary-drum furnaces, i.e. horizontal or slightly inclined
    • F27B7/14—Rotary-drum furnaces, i.e. horizontal or slightly inclined with means for agitating or moving the charge

Definitions

  • This invention relates to the field of metallurgy.
  • this invention relates to the field of powder metallurgy.
  • this invention relates to a rotary kiln based process for powder metallurgy processes.
  • this invention relates to a countercurrent reactor.
  • Figure 1 illustrates a flow diagram of the Pyron process.
  • mill scale In the Pyron process (100), mill scale (raw material, 12) is basically obtained from steel mills which produce sheets, rods, wires, plates and pipes.
  • the mill scale mainly consists of Fe 3 O4, and also contains oxides of tramp elements normally associated with steel, especially Si, Mn and Cr in the form of very finely dispersed oxides; which are difficult to reduce.
  • the mill scale is cleaned (14) dried and ground up (16, 18) to a desired particle size in a continuous ball mill.
  • Oxidation (22) of the mill scale at 870 to 980 °C converts Fe O and Fe 3 0 4 to ferric oxide (Fe 2 0 3 ). This process is essential to ensure uniform properties of Pyron-iron Powder.
  • Reduction (24) of ferric oxide by hydrogen is done in an electric furnace (30 - 40 meter long) at 980°C . (continuous belt furnace). Hydrogen is supplied by NH 3 cracking plant and reduction is done at 980°C.
  • the reduction product is ground and mechanically densified (26, 28) to make it suitable for production of structural parts.
  • This process
  • Reference numeral 32 refers to storage.
  • Reference numeral 34 refers to a step of blending.
  • Reference numeral 36 refers to packaged final product.
  • the total time a car is present in the kiln is 68h.
  • Gas burners heat the 150m tunnel at a temperature of 1200-1260°C and remaining length is cooled by air circulation. Within the hot zone, several chemical reactions occur and metallic iron is formed in the form of sponge cake.
  • the Hoganas process utilizes mixing of magnetite ore with carbon and lime, long processing time of 60 hrs plus and ceramic tubes are used to store raw material for processing.
  • An object of the invention is to provide a ‘green’ technological process.
  • Another object of the invention is to improve production.
  • a countercurrent reactor for powder metallurgy processes comprising a rotary kiln with variable angle, said rotary kiln being provided on a bed configured with a movable mechanism, at its second end, in order to provide said variable angle to said rotary kiln; thereby making flow of input powder, from its first end, to be gravity fed in order to achieve controlled angled flow rate for said input powder.
  • said movable mechanism is selected from a group of mechanisms consisting of a hydraulically movable mechanism, pneumatically movable mechanism, and mechanically movable mechanism.
  • said reactor comprises an input for flow of gases at said first end.
  • said reactor comprising an input for flow of gases at said first end, in that, said gas being selected from a group of gases consisting of Hydrogen gas, Nitrogen gas, Argon gas, and Oxygen gas.
  • said reactor is an angularly displaceable reactor.
  • said reactor comprises baffles located inside a chamber of said reactor so that input powder does not slide, instead travels through a reaction zone, configured by said chamber, by tumbling; thereby avoiding agglomerated sliding.
  • said rotary kiln comprises insulation at its either end.
  • two separate rotary kilns are placed in series, spaced apart by a conveyor belt, there between, so that after oxidation, reduction can be carried out.
  • two separate rotary kilns are placed in series, spaced apart by a conveyor belt, there between, characterised in that, a first rotary kiln being configured to provide a first step of oxidation, of said input powder in order to obtain oxidized powder, and a second rotary kiln, in series with the first rotary kiln, being configured to provide a second step of reduction on received oxidized powder from said first rotary kiln in order to obtain a reduced powder.
  • FIG. 1 illustrates a flow diagram of the Pyron process.
  • Figure 2 illustrates a process of a countercurrent reactor of this invention
  • Figure 3 illustrates a setup of a countercurrent reactor of this invention
  • Figure 4 illustrates a graph according to a non-limiting exemplary embodiment of the countercurrent reactor of this invention.
  • FIG. 2 illustrates a process (200) of this invention.
  • Figure 3 illustrates a setup (300) of this invention.
  • a rotary kiln (300) with variable angle there is provided a rotary kiln (300) with variable angle.
  • Rotary kiln angle can be changed as per requirement.
  • a bed (301) is provided on which the rotary kiln (300) is placed. This bed is supported by a hydraulic / pneumatic / mechanical arrangement (302) at its one end in order to provide this variable angle.
  • Input is provided at one end (304) and flow of gases is provided at the other end (306).
  • this flow of gas is Oxygen gas.
  • this flow of gas is Hydrogen / Nitrogen gas.
  • the rotary kiln is angularly displaceable (308). This is provided so that all the internal particles, being subject to oxidation and / or reduction, rotates / angularly displaces; thereby, allowing opportunity for each particle from all sides to interact with gases. Furthermore, it provides enhanced particle - gas interaction, hence improved productivity.
  • the rotary kiln comprises baffles (310) located inside the chamber so that so that powder does not slide; this avoids agglomerated sliding
  • the rotary kiln comprises insulation (312) at its either end.
  • a rotary kiln process is devised in which charge is fed from one end and reactive gases entered from opposite end.
  • oxidation reaction is carried out in rotary kiln process in which Fe20 3 is obtained with more than 95% purity and, secondly, reduction is carried out by hydrogen with nitrogen as carrier gas. This gives rise to iron powder purity more than 98%.
  • both the stages can be carried out in the rotary kiln process or it can be decentralized wherein oxidation in performed in a first kiln and reduction is performed in a second kiln. Both these kilns can be kept in series.
  • the same rotary kiln process can be used for oxidation and then for reduction.
  • process completes either in one step or both processes can be carried out in separate rotary kilns and the same can be placed in series, by placing a conveyor belt (318), there between, so that after oxidation, reduction can be carried out.
  • mill scale is milled to powder size of 100 micron.
  • the powdered output is oxidized, in a first kiln of the rotary kiln (50), at a temperature of 1100°C.
  • a third step (206) the oxidized output is reduced, in a second kiln of the rotary kiln (50) at a temperature of 875°C.
  • the resultant powder can be compacted to pellets and then it can be melted to make ingots.
  • input is Fe 3 0 4
  • input is Fe 2 0 3 which is actually an intermittent product obtain at the end of 1 t step.
  • Two-directional input is provided (one input being material and one input being gas)
  • the countercurrent reactor of this invention for Mill scale was used for the processes of oxidation and reduction.
  • Figure 4 illustrates a graph according to this non-limiting exemplary embodiment, in which the following was observed:
  • the TECHNICAL ADVANCEMENT of this invention lies in the provisioning of a rotary kiln with variable angle.
  • the rotary kiln comprises at least two kilns for series-processing or simultaneous-processing. This same rotary kiln process can be used for oxidation and then for reduction. In both these cases, process completes in one step. Or both processes can be carried out in separate rotary kiln and same can be placed in series, so that after oxidation, reduction can be carried out. This is a green technology and no use of carbon.
  • Purity of Fe203 is more than 95 % as intermediate product. Purity of reduced iron powder gives purity of more than 98% depending upon the origin of mill scale.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Muffle Furnaces And Rotary Kilns (AREA)

Abstract

L'invention concerne un réacteur à contre-courant pour des procédés de métallurgie des poudres, ledit réacteur comprenant un four rotatif (300) à angle variable, ledit four rotatif (300) étant ménagé sur un lit (301) configuré avec un mécanisme mobile (302), au niveau de sa seconde extrémité (304), afin de fournir ledit angle variable audit four rotatif (300), ce qui amène un écoulement de poudre d'entrée, à partir de sa première extrémité (306), à être alimenté par gravité afin d'obtenir un débit d'écoulement à angle régulé pour ladite poudre d'entrée.
PCT/IN2020/050517 2019-11-28 2020-06-11 Réacteur à contre-courant WO2021106008A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN201921048998 2019-11-28
IN201921048998 2019-11-28

Publications (1)

Publication Number Publication Date
WO2021106008A1 true WO2021106008A1 (fr) 2021-06-03

Family

ID=76130129

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IN2020/050517 WO2021106008A1 (fr) 2019-11-28 2020-06-11 Réacteur à contre-courant

Country Status (1)

Country Link
WO (1) WO2021106008A1 (fr)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2230142A (en) * 1939-10-24 1941-01-28 Gen Refractories Co Rotary kiln lining
US4995809A (en) * 1988-11-05 1991-02-26 Kloeckner-Humboldt-Deutz Aktiengesellschaft Baffles for tube coolers, rotary tubular kilns or the like

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2230142A (en) * 1939-10-24 1941-01-28 Gen Refractories Co Rotary kiln lining
US4995809A (en) * 1988-11-05 1991-02-26 Kloeckner-Humboldt-Deutz Aktiengesellschaft Baffles for tube coolers, rotary tubular kilns or the like

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
HEWITT, GEOFFREY FREDERICK: "A-to-Z Guide to Thermodynamics, Heat and Mass Transfer, and Fluids Engineering : AtoZ", 1 January 2006, BEGELLHOUSE, US, ISBN: 978-0-8493-9356-3, article SHIRES J. L.: "KILNS : AtoZ", XP055832249, DOI: 10.1615/AtoZ.k.kilns *

Similar Documents

Publication Publication Date Title
RU2435868C1 (ru) Способ получения брикетированного восстановленного железа и способ получения чугуна
WO2010117008A1 (fr) Procede pour la production de fer metallique
JP5059379B2 (ja) 高炉装入原料用ホットブリケットアイアンおよびその製造方法
US3753682A (en) Ported rotary kiln process for direct reduction of oxides of metallic minerals
CN102994680A (zh) 一种生产直接还原铁的可控气氛转底炉工艺
CN107779536A (zh) 一种直接还原铁生产方法及装置
CN103993163A (zh) 一种铁矿石带式焙烧机-回转窑直接还原生产铁粉系统及工艺
WO2013011521A1 (fr) Procédé de réduction directe d'agglomérés composites des fines de minerai de chromite oxydé dans un four tunnel utilisant un agent réducteur carboné pour la production d'agglomérés / de produit de chromite réduit applicable dans la production de ferrochrome ou de charge-chrome
WO2021106008A1 (fr) Réacteur à contre-courant
US20050193862A1 (en) Process for producing sponge iron and reduced iron powder sponge iron and charging apparatus
US4747872A (en) Process and apparatus for producing high purity iron
CN102181776A (zh) 一种还原球团法生产高品位镍及不锈钢的工艺方法和装置
CN114395697A (zh) 一种还原脱锌工艺碳减排的方法
KR20230159407A (ko) 금속 산화물 재료 환원 수단
KR100402167B1 (ko) 이동형 노상로의 조업방법
JP3732024B2 (ja) 還元鉄ペレットの製造方法
CN109402317A (zh) 高效能金属氧化物碳热还原生产金属的方法及其使用的多孔料饼
JP2000034526A (ja) 還元鉄ペレットの製造方法
KR101714995B1 (ko) 환원철의 제조 방법 및 제조 설비
JP2001040426A (ja) マンガン鉱石予備還元品の製造方法
JP2020056052A (ja) 酸化鉱石の製錬方法
CN115216572B (zh) 一种铁氧化物直接还原的方法和系统及其用途
JP7211178B2 (ja) ニッケル酸化鉱石の製錬方法
JP2010255075A (ja) 還元鉄成形体の製造方法、及び銑鉄の製造方法
JP2024010513A (ja) ニッケル酸化鉱石の製錬方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20894427

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20894427

Country of ref document: EP

Kind code of ref document: A1