US 2502704 A
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Description (OCR text may contain errors)
April1 9 1950 Q G. G. CHISHOLM 2,502,704
APPARATUS FOR CONCENTRATING ORES CENTRIFUGALLY Filed Sept. 15, 1947 v 2 Sheets-Sheet 1 G-G. CHISHOLM ATT'YS Apifl 4, 11.950 G. G. CHISHOLM 2,502,704
APPARATUSYFOR CONCENTRATING ORES CENTRIFUGALLY Filed Sept. 13, 1947 2 Sheets-Sheet 2 INVENTOR G. G CHISHOLM Patented Apr. 4, 1950 APPARATUS FOR CONCENTRATING ORES CENTRIFUGALLY Gilbert Gordon Chisholm, London, Ontario, Canada, assignor to Ferros Metals Research (30., Limited, Toronto, Ontario, Canada, a'company of Ontario Application September 13, 1947, Serial No. 773,887
2 Claims. (Cl. 233-27) This invention generally relates to a method for separating ore pulps into a concentrate and a tailing, and to an apparatus for accomplishing the method of the invention. More particularly, the invention discloses a method and apparatus for centrifugally concentrating low grade ores in a continuous manner.
Most of the readily accessible high-grade ironore deposits in North America have been depleted, and the tenor of iron-ores beneficiated has been continually decreasing. Such lowgrade deposits are now being worked that standard concentrating methods have been found wanting when applied to these ores, since substantial losses accompany the employment of these methods.
. It is therefore an object of the present invention to beneficiate low-grade iron ores with a minimum of loss of values.
Afurther object of the invention is to inexpensively and efliciently concentrate low-grade iron ores.
A further object of the invention is to continuously separate various ores into a concentrate and a tailing.
A further object of the invention is to provide an apparatus of simple construction adapted to concentrate ores through centrifugal action.
A still further object of the invention is to provide a centrifugal ore concentrator which is sturdy, durable, and economical of manufacture.
With these and other objects in view, the invention generally comprises continuously separating an ore pulp into a concentrate and a tailing by leading the pulp into a plurality of openended tubes angularly disposed on a rotating means, rotating said tubes at high speeds, continuously removing a tailing from the ends of the tubes, and continuously removing a concentrate from an area of the inner peripheral edges of the tubes.
Other objects of the invention will be apparent from a study of the following detailed specification taken in conjunction with the accompanying drawings.
In the drawings:
Figure l i a vertical section of an apparatus adapted to carry out the method of my invention,
Figure 2 is an enlarged vertical section of the concentrate withdrawal means, and
Figure 3 is a plan section of the concentrate withdrawal means.
Referring particularly to Figure l, numeral l represents a vertical spindle. A sleeve H is rotatably mounted on spindle ill by means of thrust bearings 62 and bushings l3 and 14. A drive pulley [5, adapted to receive a belt, is attached to sleeve ll, whereby the sleeve may be beltdriven. Two discs, or spiders l6 and Il attached to sleeve 9!, support a plurality of open-ended concentrating tubes l8 at an angle to the axis of spindle it). A feed distributor head I!) is fixedly mounted on the rotatable sleeve It and rotates therewith. Distributing tubes 20 connect distributor head IS with each of the concentrating tubes l8.
A cylindrical screen 2| may be mounted within each tube 18. Each tube I 8 is provided with a concentrate discharge slot 22 in the wall of the tube adjacent the outer end thereof. A spigot collar 23 is concentrically mounted on said tube in the area of slot 22. A discharge spout 2 extends from spigot'collar 23 and the latter i further provided with an orifice 25. A splitter 26 is disposed within tube 3 to direct the concentrate toward discharge spout 24. The positions of a splitter in the form of a deflector plate 26 and spout 2 3, relative to discharge slot 22, maybe varied by means of a stud 21, attached to the splitter and projecting through orifices 25 in spigot collar 23. The outer end of stud 21 is threaded and is provided with a nut 28, by means of which stud 21 may be clamped to spigot collar 24. A concentrate launder 29 is arranged below concentrate discharge spouts 24, and a tailings launder 30 is disposed below the outer ends of the tubes.
Tubes 18 have been shown in the drawing as straight in form. Actually, I prefer to use curved tubes angularly disposed on sleeve II, and I prefer to so curve the tubes that they approach the vertical at their outer ends. In this construction, concentrate discharge spout 24 extends outwardly substantially at right angles to spigot collar 23.
The method of operation is as follows. The machine is set in motion, causing the tubes I8 to revolve about the fixed spindle In. (With low grade iron ores, I prefer to use speeds somewhat i excess of 1000 revolutions per minute. Considerably greater or lesser speeds are employed, however, with other ores.) Comminuted ore, in the form of a liquid pulp, is fed into the distributor head l9, and is thrown by centrifugal force to the sides of the latter, and thence through distributor tubes 20 to concentrating tubes l8. As the pulp passes down the tubes l8 under the influences of gravity and of centrifugal force, particles of relatively high specific gravity tend to concentrate along the inner walls of tubes 18 through the screen 2|.) As the pulp approaches a i the outer ends of the tubes, the concentrating, or sorting through specific gravity differences, is completed. If a horizontal section is taken through the pulp mass at this time, the mass will be found to be in the form of a segment of a circle, the chord of said segment being substantially radially disposed with regard to said spindle; and if an analysis were made of the values of material constituting this segmental form, it would be found that the values were concentrated over the area of the segment remote from the spindle whereas the area nearest the spindle was substantially deplete of values. The downward travel of the pulp mass is interrupted by the splitter '26 which directs the enriched portion of the pulp to concentrate discharge slot 22, whence it is thrown through concentrate discharge spout 24 into concentrate launder 29. The depleted portion of the pulp passes by the splitter, and is thrown out of the ends of the tubes into tailings launder 30. The tailings may be dumped, or may be repassed through the same concentrator, or a similar one, in order to further clean the tailings.
Modifications of the method and of the apparatus will be apparent to persons of mechanical ability and persons familiar with the dressing of ores. It is therefore intended that the present disclosure should not be limited in any way other than that indicated by the scope of the following claims.
What I claim as my invention is:
1. Apparatus for continuously dressing an ore pulp into a concentrate and a tailing, comprising, a substantially vertical rotatable member, at least one tubular member mounted at an acute angle on said rotatable member and having an inner open end and an outer open end, means for feeding an ore pulp into the inner open end of said tubular member, a splitter in the form of a deflector plate mounted within said tubular member near its outer end, and extending only partially across the interior of said tubular member to allow passage of tailing and discharge of the same from the outer end of said tubular member, a discharge opening formed in the wall of said tubular member adjacent said deflector plate to accommodate concentrate deflected by said plate exteriorly of said tubular member, an
adjustable spigot collar in the form of a sleevelike member slidably mounted on said tubular member and having a discharge opening and a spout mounted thereon about the opening designed to register with the discharge opening in said tubular member, and means passing through said discharge opening for connecting said spigot collar to said deflector plate.
2. Apparatus as claimed in claim 1, in which the discharge opening extends circumferentially of the tubular member a radial dimension of substantially 180 degrees.
GILBERT GORDON CHISHOLM.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 730,114 Guttner June 2, 1903 935,311 Raist Sept. 28, 1909 943,083 Kuch Dec. 14, 1909 1,014,827 King Jan. 16, 1912 1,014,849 Richardson Jan. 16, 1912 1,111,600 Mauss Sept. 22, 1914 1,139,206 McGovern May 11, 1915 2,185,279 Strezynski Jan. 2, 1940