US2244429A

US2244429A - Amalgamator and concentrator

Info

Publication number: US2244429A
Application number: US332133A
Authority: US
Inventors: Clarence D Overton
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-04-29
Filing date: 1940-04-29
Publication date: 1941-06-03
Anticipated expiration: 1958-06-03

Description

June 3, 1941. Q Q QVERTQN V2,244,429

AMALGAMATOR AND CONCENTRATOR Filed' April 29, 1940 Patented llune 3, 1941 NiTED STATES PATENT ortica AMALGAMATOR AND fCONCENTR/ATOR Clarence D. Overton, Los Angeles, Calif.

Application April 29, 1940, Serial No. 332,133

3 Claims.

The present invention relates generally to a method and apparatus for recovering metallic gold from gold bearing ore, and more particularly to the amalgamation and concentration of free gold, with the object, among others, of accomplishing the same in a manner which will effectively do away with all danger of the flowering of the mercury and Waste thereof as well as of free gold.

It is well known in the practical art that anything in the way of methods, machines or apparatus for the above purpose, permitting or tending toward separation of the mercury into small particles, or flowering of the mercury as it is called, developes considerable loss in both mercury and gold. In small particles, the gold and mercury may iind their way into, and outflow with, the dross or tailings. It is one of the primary purposes of the present invention to eliminate this loss by the provision of a method and apparatus tending to keep the mercury together and prevent separation thereof, as well as insure intimate contact therewith, of every particle of free gold in the ore handled.

A further object of the invention is the provision of a method and apparatus according to which every portion or particle of the ore treated is forced to pass through a body of mercury at a time when both ore and mercury are similarly and powerfully acted upon to bring about their intimate churning or grinding together.

A further object of the invention is the maintenance of a body of mercury in a manner dennitely presenting an axial or central area substantially removed from the perimeter of the body, and the feeding of ore, containing free gold, into the said axial or central area of the maintained body of mercury and thereafter conlined, during forceful intermixing of the ore and mercury, against movement out of the mercury except in a direction radially of the mercury body from its said central area to its perimeter, and in this way carry on thorough, eicient amalgamation in a manner which is novel both as to the method as well as to the apparatus.

A still further object is the provision of an apparatus of the above character which may be made in various sizes having diierent capacities and which will be equally efcient in all such sizes. Y

A still further object of the invention is the provision of an apparatus in which successful amalgamation and concentration may be carried out with minimum power requirements, and with slow grinding of the ore and mercury in a more (Cl. R09 191) or less frictionless contact with the mixing, churning or grinding parts or elements.

While appreciating that my invention is readily adaptable to numerous modifications and changes, I will now describe the best mode so far devised by me for its practical success, the

description in detail referring to the accompanying drawing, illustrating the invention and forming a part of this specication. In the drawing,

Figure 1 is a side elevation of the apparatus of this invention.

Figure 2 is a top plan view thereof with the upper gears removed.

Figure 3 is a vertical, sectional View taken centrally therethrough on the line 3--3 of Figure l.

Figure 4 is a vertical, sectional view taken centrally therethrough along a line at right angles to the section of Figure 3, and,

Figure 5 is a horizontal sectional View taken substantially on line 5--5 of Figure l.

Referring now to the above figures of the drawing, I preferably utilize an upwardly opening, vertically cylindrical casing Il) within and upon the base of which there is disposed a stationary or bottom grinding plate Il. This plate as plainly seen extends across the full diameter of the casing base and is to be formed of a hard, wear-resisting material for a reason which will presently appear.

AThe upper face of the ybottom plate Il forms a horizontal flat surface on which a plurality of hard steel grinding balls I2 are disposed, preferably in number to substantially cover the surface and at the same time allow somewhat free movement of the balls for independent rotation on constantly varying axes under the effect of an upper grinding plate i3 overlying, and resting of its own weight evenly upon, the grinding balls I2.

The upper grinding plate I3 is of substantially reduced diameter with respect to the lower plate, and is supported in coaxial relation to the latter upon the lower end of its axially upstanding shaft I4, so that an annular, upwardly opening channel I5 is thus formed between the perimeter of the upper grinding plate I3 and the casing wall. This channel, it will be noted, forms and affords the only communication from the space between the plates Il and I3 into the casing I0 above the plate I3.

The shaft I4 is hollow and forms a feed tube downwardly through which the ore from the mill is constantly fed from the lower end of the y tube into the axial or central area of the space between the grinding plates II and I3, since the lower end of the feed tube opens downwardly through the upper plate I3 and, as plainly seen in Figures 3 and 4, extends below the plate I3 which it supports, in order to prevent crowding of the balls I2 below the feed tube where material is fed to the space between the plates I I and I3. Obviously the ore so fed into the space between the plates II and I3 is intimately intermixed with the mercury, maintained at a substantial level above the bottom plate I I.

The above action in the present apparatus means more than mere mixing of the ore and mercury. The freely revolving and rotating balls, which form an anti-friction supportfor the upper plate I3, actually grind the ore and mercury together slowly and thoroughly without danger of either getting away fromtheother'as long as they are in the space between the plates. In the course of the above action, the ore is of course prevented from movement out of the mercury in any direction except radially from the center to the perimeter of the plates II and I3, and it is along this path that the mixture slowly nds its way to the outer annular channel I5 where it moves upwardly into the casing above the upper plate I3.

It is plain that in the aboveoperation every particle of free gold will lbe brought into intimate contact with the mercury with which it amalgamates. Thus as the mixture rises through the channel I5 around plate I3 the heavier amalgam will separate from the dross or tailings, the former passing upwardly along the inner surface of the wall of casing IB for discharge through a side outlet or concentrate take-olf I6; The tailings, being somewhat lighter, rise upwardly along the upper conical cover II of plate I3 to finally discharge through a discharge nipple I8 in communication with a tailings discharge pipe I9, said nipple having its inner receiving end opening within the casing adjacent to the upper inner end of the cone I1.

'Ihe casing lil may have laterally outstanding flanges 2) at diametrically opposite points of its upper open end. 'I'o these flangesmay be bolted the end portions of a cross bar or bridge 2i. This bridge has an openingthrough which the hollow feed shaft I4 rises, andV forms a support for an upstanding bearing cage or cylinder 22- around shaft I4. In the cylinder 22 are upper and

lower bearings

23 and 24, in contactv with the shaft Ill at vertically spaced points of the latter.

Above the bearing cylinder 22, the shaft I4 is shown with a fixed gear 25 which may be of the bevel type to engage a similar gear 26 of reduced size, on a drive shaft 2'I extending from, and actuated by, any suitable source of power. However other types of gearing may be used, since the present apparatus lends itself to elcient operation with small power requirements.

The bridge 2| also serves as a support for rigidv pendant stirring arms 28 in series at opposite sides of the shaft I4, with their lower ends terminating near the surface of the cone I'I at several points thereof, so as to prevent the tailings from building up on the cone surface and in this manner insuring ready discharge of said tailings through the discharge pipe I9.

In order to maintain uniformfeed ofore into the space between the grinding plates as previ# ously mentioned, I preferably utilize, within the feed shaft I4, means which, inconnection'with' this rotating shaft, will control such feed and at the same time prevent clogging thereof.

For the above purpose I may employ a stationary, twisted or spiral feed strip or ribbon 29 within the feed shaft I4, which strip or ribbon may be secured in any suitable manner as by anchoring the lower end of the same to the bottom plate II. Any other suitable means may, however be used for this purpose, either stationary or movable of itself.

It is believed that, from the foregoing description, the advantages in operation of the present apparatus will be readily recognized. Every particle of free gold is forced into intimate contact with the mercury in an area in which ore and mercury are intermingled during slow rotation of the upper grinding disc or plate, and rotation and roaming of the grinding balls I2, well adapted to eiiicient functioning with low power demands and without danger of loss of free gold or through flowering of the mercury.

The apparatus of this invention economical in its manufacture as well as its use, and is not only capable of a long effective life, but is singularly free of parts likely to need frequent repair or replenishment, and is a fitting complement to the method it so well carries to effective conclusion.

Having thus fully described my invention, what I claim and desire to `secure by Letters'Patent is,

1. Incombination,` a casing, means forming a mercury space horizontally within the lower portion of the-casing including superimposed plates of whichy the upper plate is rotatable, with its perimeter spaced from the wall of the casing to form a mixture dischargechannel opening upwardly into they casing, balls freely disposed in said mercury space and upon which theupper plate rests, a hollow upright feed shaft rotating said upper plate and -opening downwardly therethrough into the center of the mercury space, an inverted cone atop the rotating upper plate having a wide lower end onsaid plate and having a narrow upper end closely surrounding the shaft at a point spaced vertically above the rotating plate, said casing havinga concentrate take-off through itswall above the-upper plate, and a tailings discharge member extending radially inwardly through the upper portionpoflthe wall of the casing andY having its inner receiving end opening'within the casing adjacent to the upper end of the cone where it surrounds the shaft.

2; In combination, acasing, means forming a mercury space horizontally within the lower portion of the casing including superimposed plates of which the upper plate is rotatable' with its perimeter spaced from the wall of the casing to forma circumferential mixture discharge `channel opening upwardly into the casing, balls freely disposed in said mercuryt space and upon which the rotatable plate rests, and a hollow upright feed shaft rotating said upper plate and opening downwardly therethrough with its lower end extending below the upper plate and projecting into -the center ofthe mercury space l to` prevent the balls from crowding inthe lower discharge end of the said feed shaft.

3. In combination, a casing,` means forminga mercury space horizontally within the lower portion of the casing including superimposed ,plates ofA which the upper plate is rotatable, with its perimeter spaced from the wall ofthe casing to form a mixture discharge channel opening upwardly intothe casing, balls freely disposed in said mercury space and upon Which the upper plate rests, a hollow upright feed shaft rotating said upper plate and opening downwardly therethrough into the center of the mercury space, a cone atop the rotating upper plate and around the shaft, said casing having a concentrate takeoff through its Wall above the upper plate, a tailings discharge member extending through the upper portion of the Wall of the Casing and having its inner receiving end opening Within the 10