Method and apparatus for dissolving nickel in molten zinc

• US 4,717,540 A
• Filed: 09/08/1986
• Issued: 01/05/1988
• Est. Priority Date: 09/08/1986
• Status: Expired due to Term

• Current Assignee: Teck Cominco Metals Ltd.
• Original Assignee: Cominco Ltd. (Sgl Carbon Se)
• Inventors: McRae, Dale L., Willans, Robert D. H., Mawer, Eric L.
• Primary Examiner(s): ROSENBERG, PETER
• Application Number:
  US06/904,536
• Time in Patent Office: 484 Days
• Field of Search: 75/61, 75/93 R, 420/590, 420/129
• US Class Current: 75/663
• CPC Class Codes: F27D 27/00 Stirring devices for molten material F27D3/14 takes precedence
• CPC Class Codes: F27D 3/0026 Introducing additives into the melt

Abstract

A rotatable device is suspended in a melt of zinc and the device is rotated to draw a vortex in the melt. The device comprises a hollow cylinder having an open top and a closed bottom. An array of openings in the cylinder side wall is adapted to allow zinc melt to pass through. Nickel is added in particulate form into the vortex in the device. The openings in the cylindrical wall are adapted to retain the nickel particulates in the device to be washed with molten zinc until the particulates are substantially dissolved. The temperature is kept at a minimal value, i.e., no superheat is required to dissolve the nickel homogeneously throughout the zinc melt. After the nickel is dissolved, the nickel-zinc melt is solidified in zinc slabs. The zinc slabs containing nickel have narrow standard deviations from their specification. The dissolving proceeds more efficiently with formation of less dross and less off-specification material, proceeds faster and in less time than heretofore possible, and allows production on a continuous basis.

Claims

1. A method for the dissolution of nickel in molten zinc which comprises the steps of establishing a melt of zinc in a vessel;

submerging a rotatable device in said melt;

said rotatable device consisting of a hollow cylinder having a side wall with an upper end and a lower end, said cylinder being open at the upper end and closed at the lower end, said side wall having an array of equispaced openings adapted to retain nickel added in particulate form in said device in said rotatable device and to allow said molten zinc to pass through said openings, and means attached to the bottom plate for rotation of the rotatable device;

rotating said rotatable device at a predetermined speed sufficient to draw at least a partial vortex in said melt of zinc and said rotatable device;

feeding nickel in particulate form into said vortex in an amount sufficient to provide a melt of desired composition of zinc containing dissolved nickel;

washing said nickel added in said device with said melt of zinc while rotating said device causing said molten zinc to flow into the top of said device and out through said openings;

said washing with molten zinc while rotating said device causing dissolution of said nickel in said rotatable device and formation of a melt of zinc containing said predetermined amount of nickel; and

withdrawing a melt of said desired composition from said vessel.

2. A method as claimed in claim 1, wherein said rotatable device has a diameter relative to the diameter of said vessel in the range of about 1.5:

1 to about 3.5;

1.

3. A method as claimed in claim 1, wherein said rotatable device is rotated at a predetermined speed in the range of about 100 to about 600 revolutions per minuted.

4. A method as claimed in claim 1, wherein, in addition to said predetermined amount of nickel, a predetermined amount of lead is dissolved in said melt, said predetermined amount of nickel and said predetermined amount of lead being sufficient to form a melt of predetermined composition containing nickel and lead dissolved in zinc.

5. A method as claimed in claim 1, wherein an inert gas is supplied in said vessel.

6. A method as claimed in claim 1, wherein said dissolution is carried out continuously by adding a measured amount of melt of zinc continuously to said vessel, adding nickel in particulate form continuously to the rotating, rotatable device at a predetermined rate sufficient to produce a zinc melt of the desired composition of nickel dissolved in zinc, continuously removing a volume of said zinc melt containing dissolved nickel from said vessel, and maintaining the level of melt in said vessel substantially constant, said zinc melt containing dissolved nickel removed from said vessel having a small standard deviation from composition specification.

7. A method as claimed in claim 1, wherein said zinc and said nickel form agglomerates and said agglomerates are retained in said device until substantially dissolved.

8. A method as claimed in claim 6, wherein in addition to said nickel, lead is continuously added to said vessel, and a melt of desired composition of nickel and lead dissolved in zinc is produced and is removed from said vessel.

9. A method as claimed in claim 6, wherein said zinc and said nickel form agglomerates and said agglomerates are retained in said device until substantially dissolved.

10. A method for dissolution of nickel in molten zinc which comprises the steps of establishing a melt of zinc in a vessel;

submerging a rotatable device in said melt;

said rotatable device comprising a hollow cylinder having a side wall with an upper end and a lower end, said cylinder being open at the upper end and closed at the lower end, said side wall having an array of equispaced openings adapted to allow said melt to pass through said openings, and said cylinder having a diameter relative to the diameter of the vessel in the range of about 1.5;

1 to about 3.5;

1;

rotating said cylinder at a predetermined speed in the range of about 100 to about 600 revolutions per minute sufficient to draw at least a partial vortex in said melt into said rotatable device, causing said melt to flow into the top of said device and out through said side wall openings;

adding a predetermined amount of nickel in particulate form in said rotatable device for the dissolution of said nickel in said molten zinc, said predetermined amount being sufficient to provide a melt of nickel and zinc of a desired composition; and

withdrawing said melt of desired composition from said vessel.

11. A method as claimed in claim 10, wherein, in addition to said predetermined amount of nickel, a predetermined amount of lead is dissolved in said melt, said predetermined amount of nickel and said predetermined amount of lead being sufficient to form a melt of predetermined composition containing nickel and lead dissolved in zinc.

12. A method as claimed in claim 10, wherein said dissolution is carried out continuously by adding a measured amount of melt of zinc continuously to said vessel;

adding nickel in particulate form continuously to the rotating, rotatable device at a predetermined rate sufficient to produce a melt of the desired composition of nickel dissolved in zinc;

continously removing a volume of said zinc melt containing dissolved nickel from said vessel; and

maintaining the level of melt in said vessel substantially constant, said zinc melt containing dissolved nickel removed from said vessel having a small standard deviation from composition specification.

13. A method as claimed in claim 12, wherein in addition to said nickel, lead is continuously added to said vessel, and a melt of desired composition of nickel and lead dissolved in zinc is produced and is removed from said vessel.