US2626052A - Flotation machine - Google Patents

Description

Jan. 20, 1953 R. CARBONNIER 2,626,052

' FLOTATION MACHINE Filed Dec. 9, 1948 Patented Jan. 20, 1953 UNITED STATES PATENT OFFICE Application December 9, 1948, Serial No. 64,315 In France April 11, 1947 2 Claims. 1

My invention relates to improvements in flotation machines intended for the extraction of certain ore components and its chief object consists in improving such machines particularly with a view to more rapidly exhausting the pulp undergoing treatment and increasing the useful amount of material extracted.

According to a primary object of the invention, the mixture of pulp and air or like fluid, stirred by a rotary member is projected by said rotary member on to a, blading provided with means for adjusting the angular setting of its blades in order to damp more or less the speed of the jet of the projected mixture. The turbulence thus produced generates a very fine atomization of the air or gas contained in the mixture.

This arrangement is conveniently arranged at the lower part of the machine tank and a perforated partition or hood mounted above it stops the bubbles that are too large and allows only the passage towards the surface of the liquid in the tank of fine bubbles providing for the formation of a rich froth.

The flow of air or gases fed to the stirring or centrifuging arrangement is mixed before entering said arrangement with the liquid from the tank that is sucked by said arrangement through ports provided in the air or gas feed-pipe.

Other objects and advantages of the invention will'be apparent during the course of the following description. In the accompanying drawing forming a part of this application and in which like numerals are employed to designate like parts throughout the same,

Fig. 1 is a vertical cross-sectional view of a preferred embodiment of the invention.

Fig. 2 is a horizontal cross-section through line IIII of Fig. 1, the central zone of said figure showing partial cross sections at three different levels.

The pulp constituted by a mixture of water and of ore is fed into the tank I of the machine in the usual manner, for instance through a pipe la. At the same time, air or another gasiform fluid, under atmospheric pres-sure or under any other pressure as may be required for the treatment of the ore, is fed into the central tube 2 as disclosed hereinafter. The pulp and air (or like fluid) reach an impeller 3 having a vertical axis and rotatingly driven by a pulley '4. This ation thereof on to the fins 5. This mixture containing large bubbles of air or of aeriform fluid is directed at a high speed on to the blades 1 of a blading, said blades assuming a suitable adjustable angular setting and being arranged symmetrically and regularly aboutimpeller 3.

The turbulence produced by the suitable angular setting of the blades 1 provides a very fine atomization of the air or aeriform fluid contained in the mixture and an intimate intermixture between the emulsified air or like bubbles and the finest particles of ore.

The adjustable blades 1 are carried by the diaphragm 8 by means of vertical spindles 9 which are further used for their control. The diaphragm 8 is provided with ports 10 distributed regularly along a circumference around impeller 3, said ports being adapted to increase the turbulence. The angular setting of the movable blades 1 is controlled by a handwheel II, the spindle of which carries a threaded rod l2 driving longitudinally a nut 13 controlling the rod l4 bolted to the ring 15 so as to impart to the latter a rotary movement round the central axis of the machine. During this movement, the ring I 5 carries along with it through projections IS the levers l1, keyed to the spindles 9; this produces a rocking of the movable blades I through the desired angle round their spindles 9. This rocking may be effected either in the direction of rotation of the impeller 3 or, if required, in the opposite direction in a manner such that the movable blades have a tendency to damp to a more or less considerable extent the absolute speed of the mixture subjected to centrifugal action in the impeller 3. The turbulence may thus be adjusted according to the treatment required by the ore.

' The motion of the air or like fluid'towards impeller 3 is enhanced by the displacement of the liquid and pulp flowing in the central tube 2 through the ports l8 thereof. These ports I 8 are located inside the tank at a level such that they collect the pulp containing non-flotated mixtures. This pulp is thus again admixed with the air or the like fluid at the same time as the fresh pulp entering the tank through pipe la, the mixture being performed as disclosed hereinabove through atomization on the fins 56 and on the adjustable blades 1.

The proportions of the mixture are adjusted by the control throttle l9 that is also provided with openings 20; aid throttle is rotatably mounted on the tube 2 so as to cause the ports 20 to register to a varying extent with the ports l8 in the tube 2 in order to adjust as required the cross-sectional area of the opening through which the pulp is to flow. This motion is controlled by the handwheel 2|, the spindle of which is threaded at 22 and constrains the nut 23 to assume a longitudinal displacement, said nut controlling the lever 24, fast with the throttle [9 which is made to rotate around the tube 2.

Radial vanes 25 arranged on the under surface of impeller 3 exert a sweeping influence on the tank bottom for preventing sanding or setting of heavier particles of the pulp, thus keeping this bottom clear of settled solids.

A stationary hood of perforated sheet metal covers the whole agitation device and allows for each kind of ore the bubble size to be adjusted 50 as to form the froth having the most favorable constitution for enriching purposes. This hood may be carried for instance by means of bolts 21 on cross members 28 that are themselves secured to the tank of the machine. Only those bubbles that are smaller than the openings in said hood may rise inside the tank to the surface of the liquid which is roughly level with an overflow spout 29.

Paddles 30 the height of which is adjustable are mounted on pivoted links 31 secured to two endless chains 32. These chains are carried along by rollers 33 keyed respectively to the main shaft 34 driven in its turn by the pulley 35 and to the auxiliary shaft 36 driven by the chain or belt 31 actuated by said pulley 35. These paddles 30 have during their operative stroke, a horizontal outward motion having a sweeping efiect' -asr regards froth produced by the flotation and. thus discharged from the machine. Their action. is of particular efiiciency in the case of compact froth that is diflicultv to collect as may be the case for various ores.

When a special gas is used for flotation purposes instead of atmospheric air, the upper end of the tube 2 is closed fluid tightly by means of a supple rubber diaphragm 38 carrying a stumng box 39 surrounding thevertical shaft of the impeller 3. The admission of gas is then performed through the lateral pipe opening 40.

The above described arrangement ensures a high speed of extraction and a very high yield for the machine.

It is to be understood that the form of the invention herewith shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

What I claim is:

1. In a flotation machine, a rotary shaft; an

impeller fixed to said shaft and provided with a plurality of generally L-shaped vanes in substantial radial arrangement, each vane including an upper part substantially parallel to the axis of said shaft and a lower part substantially perpendicular thereto; a plurality of pivotal blades arranged around said impeller on a level with said lower parts of said vanes, each blade being associated with a pivot substantially parallel to the axis of said shaft; and means connected to said pivots accessible externally of the machine for controlling simultaneously the angular setting of said blades with respect to radial planes.

2. In a flotation machine, a rotary shaft; an impeller fixed to said shaft and provided with a plurality of generally L-shaped vanes in substantial radial arrangement, each vane including an upper part substantially parallel to the axis of said shaft and a lower part substantially perpendicular thereto; a plurality of pivotal blades arranged around said impeller on a level with the lower parts of said vanes, each blade being associated with a, pivot substantially parallel to the axis of said shaft; means connected to said pivots accessible externally of the machine for controlling simultaneously the angular setting of said blades with respect to radial planes; and a discharging device cooperating with an outlet orifice at the top part of the machine, and comprising an endless conveyor extending horizontally from said outlet inwards of said machine, said conveyor being provided with a plurality of paddles adapted to effect sweeping action to Wards said outlet.

ROBERT CARBONNIER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,517,900 Gay Dec. 2, 1924 1,788,361 Sturtevant Jan. 6, 1931 2,190,852 Tucker Feb. 20, 1940 2,226,170 Lasseter Dec. 24, 1940 2,243,309 Daman May 2'7, 1941 2,269,583 Dromgold Jan. 13, 1942 2,337,806 Fahrenwald Dec. 28, 1943 2,393,976 Damon et al Feb. 5, 1946 FOREIGN PATENTS Number Country Date 443,616 Germany May 3, 1927 886,733 France July 12, 1943

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