WO2010087711A1 - Method for casting molten electrolyte - Google Patents

Method for casting molten electrolyte Download PDF

Info

Publication number
WO2010087711A1
WO2010087711A1 PCT/NO2010/000017 NO2010000017W WO2010087711A1 WO 2010087711 A1 WO2010087711 A1 WO 2010087711A1 NO 2010000017 W NO2010000017 W NO 2010000017W WO 2010087711 A1 WO2010087711 A1 WO 2010087711A1
Authority
WO
WIPO (PCT)
Prior art keywords
molten electrolyte
electrolyte
drum
solidified
particles
Prior art date
Application number
PCT/NO2010/000017
Other languages
French (fr)
Inventor
Arnt Tellef Olsen
Original Assignee
Alcoa Norway Ans
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 Alcoa Norway Ans filed Critical Alcoa Norway Ans
Publication of WO2010087711A1 publication Critical patent/WO2010087711A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C3/00—Electrolytic production, recovery or refining of metals by electrolysis of melts
    • C25C3/06—Electrolytic production, recovery or refining of metals by electrolysis of melts of aluminium
    • 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
    • F27B7/16—Rotary-drum furnaces, i.e. horizontal or slightly inclined with means for agitating or moving the charge the means being fixed relatively to the drum, e.g. composite means
    • F27B7/161—Rotary-drum furnaces, i.e. horizontal or slightly inclined with means for agitating or moving the charge the means being fixed relatively to the drum, e.g. composite means the means comprising projections jutting out from the wall
    • F27B7/162—Rotary-drum furnaces, i.e. horizontal or slightly inclined with means for agitating or moving the charge the means being fixed relatively to the drum, e.g. composite means the means comprising projections jutting out from the wall the projections consisting of separate lifting elements, e.g. lifting shovels
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B21/00—Obtaining aluminium
    • C22B21/0084—Obtaining aluminium melting and handling molten aluminium
    • C22B21/0092—Remelting scrap, skimmings or any secondary source aluminium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/20—Recycling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/25—Process efficiency

Definitions

  • the present invention relates to a method for casting cryolite-based electrolyte tapped from electrolytic cells for production of aluminium.
  • the present invention thus relates to a method for casting of molten electrolyte tapped from electrolytic cells for production of aluminium which method is characterized in that the molten electrolyte is continuously supplied to an inlet opening in one end of a rotating drum that is partly filled with particulate solid electrolyte whereby molten electrolyte solidifies in the form of particles and that the particles continuously are discharged from the other end of the rotating drum through a discharge opening which is at a lower level than the opening for supply of molten electrolyte.
  • the movement of the solidified particles in the drum by means of longitudinal lifting blades on the inside of the drum.
  • the size of the produced particles is decided by the rotational velocity of the drum and the amount of molten electrolyte that is supplied to the drum.
  • fluorine- and dust containing off-gas are sucked from the drum during the casting process.
  • Figure 1 shows a horizontal cut through a rotating drum that is used by the method of the present invention
  • Figure 2 shows a vertical cut along l-l in Figure 1.
  • FIG. 1 and 2 there are shown a rotating drum 1 resting on rotatable rollers 2.
  • the drum 1 has in one of its ends an inlet opening 3 for molten electrolyte and has in its other end an discharge opening 4 for solidified particulate electrolyte where the discharge opening 4 is at a lower level that the inlet opening 3.
  • the drum 1 is equipped with a suction arrangement 5 for removing gases and dust from the drum 1.
  • the drum 1 is further on its inside preferably equipped with longitudinal lifting blades 6 in order to secure movement of the solidified particles in the drum 1.
  • the drum 1 When carrying out the method of the present invention, the drum 1 is first filled with particulate solidified electrolyte up to a level not exceeding the discharge opening 4. The drum 1 is thereafter rotated and molten electrolyte is continuously supplied to the drum 1 via the inlet opening 3. The molten electrolyte will be distributed in the voids between the already solidified electrolyte particles and will solidify to particles that are automatically discharged through the discharge opening 4.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Electrolytic Production Of Metals (AREA)

Abstract

The present invention relates to a method for casting of molten electrolyte tapped from electrolytic cells for production of aluminium. Molten electrolyte is continuously supplied to one end of a rotating drum which is partly filled with particulate solidified electrolyte whereby the molten electrolyte solidifies in the form of particles. The solidified particles are continuously discharged through a discharge opening in the other end of the drum, said discharge opening being at a lower level that the inlet opening for molten electrolyte.

Description

Title of Invention
Method for casting molten electrolyte.
Technical field
The present invention relates to a method for casting cryolite-based electrolyte tapped from electrolytic cells for production of aluminium.
Background technology
By electrolytic production of aluminium in Hall-Heroult electrolytic cells it is used a cryolite-based molten electrolyte. During operation of such electrolytic cells the amount of electrolyte will vary. In order to obtain a good operation it is desirable to maintain a stable level of electrolyte and metal in the electrolytic cells. Surplus of electrolyte is tapped as molten electrolyte from the cells. If there at the same time is not a need to supply molten electrolyte to other electrolytic cells, the molten electrolyte must be cast for later melting and use.
Conventionally casting is done by pouring the molten electrolyte into containers. When the electrolyte is solidified it is removed from the containers and subjected to course crushing and thereafter to further crushing for example in a jaw crusher. The crushed product is a mixture of different particle sizes from coarse to fines that are stored for later use.
This conventional method for casting molten electrolyte into blocks followed by crushing of the blocks has some disadvantages. During the casting process fluorine-containing gases evolves. These gases constitute a health hazard. During the crushing it is generated a lot of dust which also represent a health hazard. In addition this method for casting and crushing is relatively work intensive and time consuming.
It therefore exists a need to provide a method for casting molten electrolyte tapped from electrolytic cells for production of aluminium where the disadvantages of the existing casting process are overcome. Description of the invention
The present invention thus relates to a method for casting of molten electrolyte tapped from electrolytic cells for production of aluminium which method is characterized in that the molten electrolyte is continuously supplied to an inlet opening in one end of a rotating drum that is partly filled with particulate solid electrolyte whereby molten electrolyte solidifies in the form of particles and that the particles continuously are discharged from the other end of the rotating drum through a discharge opening which is at a lower level than the opening for supply of molten electrolyte.
According to another preferred embodiment the movement of the solidified particles in the drum by means of longitudinal lifting blades on the inside of the drum.
The size of the produced particles is decided by the rotational velocity of the drum and the amount of molten electrolyte that is supplied to the drum.
According to a preferred embodiment fluorine- and dust containing off-gas are sucked from the drum during the casting process.
By the present invention it is obtained a solidified electrolyte in particulate form as the molten electrolyte supplied to the rotating drum is broken down and distributed by the particulate solid electrolyte that is moving in the rotating drum. Crushing of solidified blocks is thus not necessary. The process is further carried out in a closed system whereby the working environment is substantially improved.
Short description of the drawings
Figure 1 shows a horizontal cut through a rotating drum that is used by the method of the present invention, and
Figure 2 shows a vertical cut along l-l in Figure 1.
Detailed description of the invention
In Figure 1 and 2 there are shown a rotating drum 1 resting on rotatable rollers 2. The drum 1 has in one of its ends an inlet opening 3 for molten electrolyte and has in its other end an discharge opening 4 for solidified particulate electrolyte where the discharge opening 4 is at a lower level that the inlet opening 3. The drum 1 is equipped with a suction arrangement 5 for removing gases and dust from the drum 1. The drum 1 is further on its inside preferably equipped with longitudinal lifting blades 6 in order to secure movement of the solidified particles in the drum 1.
When carrying out the method of the present invention, the drum 1 is first filled with particulate solidified electrolyte up to a level not exceeding the discharge opening 4. The drum 1 is thereafter rotated and molten electrolyte is continuously supplied to the drum 1 via the inlet opening 3. The molten electrolyte will be distributed in the voids between the already solidified electrolyte particles and will solidify to particles that are automatically discharged through the discharge opening 4.

Claims

Claims
1. Method for casting of molten electrolyte tapped from electrolytic cells for production of aluminium, c h a ra cte r i ze d i n that the molten electrolyte is continuously supplied to one end of a rotating drum which is partly filled with particulate solidified electrolyte, whereby the molten electrolyte solidifies in the form of particles and that the solidified particles are continuously discharged through a discharge opening in the other end of the drum, said discharge opening being at a lower level that the inlet opening for molten electrolyte.
2. Method according to claim 1, c h a ra cte r i ze d i n that the movement of the solidified particles are increased by means of longitudinal lifting blades arranged on the inside of the drum.
3. Method according to claim 1, characterized in that fluorine- and dust containing gas is sucked off from the drum during the casting process.
PCT/NO2010/000017 2009-02-02 2010-01-18 Method for casting molten electrolyte WO2010087711A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO20090518 2009-02-02
NO20090518A NO20090518L (en) 2009-02-02 2009-02-02 Procedure for Stopping Liquid Electrolyte

Publications (1)

Publication Number Publication Date
WO2010087711A1 true WO2010087711A1 (en) 2010-08-05

Family

ID=42395802

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO2010/000017 WO2010087711A1 (en) 2009-02-02 2010-01-18 Method for casting molten electrolyte

Country Status (2)

Country Link
NO (1) NO20090518L (en)
WO (1) WO2010087711A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110252084A (en) * 2014-06-09 2019-09-20 贝克特尔矿业金属股份有限公司 Integrated gas processing

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4512695A (en) * 1981-07-23 1985-04-23 Aluminium Pechiney Apparatus for separating electrolysis bath residues on precalcined anodes
US4637591A (en) * 1984-06-22 1987-01-20 Mcmahon J Philip Dross cooler and processor
DE4227263A1 (en) * 1992-08-18 1994-02-24 Westfalia Becorit Ind Tech Cleaning of anode stubs in rotary drum - esp. to recover stubs and deposit material for reuse in electrolytic aluminium@ prodn.

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4512695A (en) * 1981-07-23 1985-04-23 Aluminium Pechiney Apparatus for separating electrolysis bath residues on precalcined anodes
US4637591A (en) * 1984-06-22 1987-01-20 Mcmahon J Philip Dross cooler and processor
DE4227263A1 (en) * 1992-08-18 1994-02-24 Westfalia Becorit Ind Tech Cleaning of anode stubs in rotary drum - esp. to recover stubs and deposit material for reuse in electrolytic aluminium@ prodn.

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110252084A (en) * 2014-06-09 2019-09-20 贝克特尔矿业金属股份有限公司 Integrated gas processing

Also Published As

Publication number Publication date
NO20090518L (en) 2010-08-03

Similar Documents

Publication Publication Date Title
EP1913166B1 (en) Method for recycling scrap containing aluminium-lithium-type alloys
JP5454747B1 (en) Grinding material for shot blasting and its manufacturing method
JP5215168B2 (en) Method and apparatus for secondary refining slag regeneration and recycling in steelmaking process by electric arc furnace
CN204449198U (en) A kind of casting sand retracting device
CN108179443B (en) The extremely upper insulation material multiple stage crushing of aluminium electroloysis removes iron and charging process
CN203003053U (en) Automatic sand screening system
JP4087000B2 (en) Ladle and ladle lining method
US10702874B2 (en) Apparatus for recycling waste raw material
WO2010087711A1 (en) Method for casting molten electrolyte
WO2002022900A2 (en) Process and rotary device for adding particulate solid material and gas to molten metal bath
CN110643757A (en) Hot-state casting residue treatment system
CN116254422B (en) Pretreatment and smelting regeneration method for waste aluminum
JP2000073109A (en) Production of granular body of magnesium or magnesium alloy
CN115725846B (en) Recycling method of waste building aluminum profile aluminum alloy
WO2022044931A1 (en) Atomization device, manufacturing method of metal powder, and manufacturing method of valuable metal
EP2599884A1 (en) A briquette and a method of manufacturing same, in particular suitable for inductive melting
CN208980783U (en) A kind of thick lithium impurity removing equipment of lithium metal
JP2022039952A (en) Atomization apparatus, method of producing metal powder, and method of producing valuable metal
KR101668579B1 (en) Method for manufacturing aluminum ingot from aluminum dross
CN103212716A (en) Method of preparing metal zinc powder
JP3568469B2 (en) Aluminum dross processing equipment
CN210215501U (en) Slag remover crushing and blowing device
KR101280384B1 (en) Method for removing molten metal in slag pot
JP2009074135A (en) Briquette and method for production thereof
AU2022397819A1 (en) Storage-stable spent potlining material, method for the production thereof, and use of the same as fuel

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: 10736081

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

32PN Ep: public notification in the ep bulletin as address of the adressee cannot be established

Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A, DATED 04-11-2011)

122 Ep: pct application non-entry in european phase

Ref document number: 10736081

Country of ref document: EP

Kind code of ref document: A1