Show jones belmont flotation on machine achane BY MALCOM H CARPENTER the jones belmont flotation machine was designed by mr A H jones during the time he was superintendent of mills for the tonopah belmont development company where its development and commercial use proved to be of economic value the machine is now being placed on the market for general use by the chas butters company ltd who have opened an office in salt lake city utah and also a completely equipped laboratory and testing plant and is in position to work out the treatment of ores by flotation or by other methods this work is under the direction of mr jones who recently moved to salt lake city utah the establishment of an office and testing plant in salt lake city by such a well UL 7 z po r 4 jones belmont flotation machine known firm together with the fact that the jones belmont flotation cell is attracting the serious consideration of mining men makes it of interest to learn the distinctive features of the machine in this article no comparison is made with other machines it is intended only to give what upon investigation vesti gation seems to be distinctive first a short description of the different parts of the machine is given with their individual function in the flotation of ore second a description of the operation of the machine description of the machine the machine consists of a hollow cylindrical tank 5 feet in diameter 18 inches high resting on an inverted truncated cone with sides at 60 degrees slope the dis metallurgical engineer salt lake T utah tance between the two bases of the cone is 40 inches the diameter of the smaller base is 18 inches concentric with this cone is an inner cone leaving an annular space of 4 inches between its sides and the sides of the outer cone also a space at the bottom of 5 inches the center of this inner cone is a cylindrical barrel 18 inches in diameter and 36 inches high the annular space between the cones is open into this barrel at the bottom this barrel is the agitation or mixing chamber of the machine and contains four baffles which extend up one half the distance of the barrel and out into the mixing I 1 chamber 2 inches they are spaced equidistance equi distance over the larger base of the inner cone from the outer edge of the mixing chamber to the annular space between the cones is a fabric blanket or apron called the air mats the space formed around the mixing chamber in the inner cone underneath these air mats is the air receiver or distributor tri butor of the machine to this is connected an air pipe from the compressor concentric but above the mixing cell is a second cylindrical barrel of 21 inches diameter so spaced that the opening between the top of the impeller barrel and its bottom forms a discharge space to deliver pulp over the blanket around the outside of the upper tank is a circular concentrate cen launder 8 inches across the bottom of which slopes both ways from a given point to the discharge point over the top of the upper tank is a bridge this bridge goes across the machine and carries the driving t mechanism for the impeller shaft the impeller shaft extends down through the center of the machine the lower end is supported by a step bearing water lubricated under pressure to prevent the entrance of grit on this shaft are mounted two sets of agitator arms one set is at the bottom of the agitation chamber the other set is just above the baffles in the agitation chamber in the driving mechanism use has been made of roller bearings completely enclosed in an oil casing which allows for the partial submerging of the gears in oil the machine is provided with a feed pipe which connects into the annular space near the bottom or vertex of the cone the discharge pipe leaves the machines at a point near the level of the air mat the discharge through this pipe is taken care of by a float valve operation of the machine it is assumed for the purpose of discussing the operation of the machine that the ore has previously been prepared for flotation the feed enters the machine through the feed pipe and is agitated by the impellers a and nd baffles the impellers act as a pump this throws the pulp out with a perceptible swirling lint motion over the air mats in very nearly a horizontal plane there are then two forces working at almost right angles to one another separating this feed the resultant effect is a spreading out of the feed in a fan shape the heavier particles being thrown by centrifugal force the farthest es an and are par partially la y separated d from the slime by this action the air finishes this separation and raises the particles into the froth zone this then tends to put the particles that are to enter the froth zone zon there with a minimum effort the remainder of the feed goes over the outer edge of the air mat into the annular space the swirling motion gravity and the suction of the impellers draw it rapidly to the agitation chamber where it is again agitated and thrown out over the air mat the swirling motion allows a very uniform cut of the pulp to be made into the tailings discharge pipe and this allows by means of the float valve a constant uniform level to be maintained in the froth zone the separation of the sulphides sulp hides or values of the ore from the gangue in this machine is accomplished dished in a constant uniform manner mechanically making a very satisfactory demonstration of the theory of the mechanical separation of the sulphides sulp hides from the gangue the impellers throw the feed out in thin layers forcing the same through the pulp in the upper chamber this action produces an excellent condition for a small amount of air to adhere to each oiled particle the swirling motion is only slightly pe perceptible at the top of the concentrate froth allowing a uniform distribution of the concentrate froth around and over the outer edge of the tank into the circular launder the automatically controlled discharge valve maintains a constant pulp level allowing a uniform discharge of concentrate cen equal to the amount being formed the average distance the froth hasto has to travel is short so it is not necessary for the froth to support itself for any distance this permits of a minimum amount of reagents the application of the air uniformly through the segregated feed causes a rapid separation of the mineral bearing particles from ane gangue of the ore it can be seen from this description of operation that there is no chance of gradual classification of the ore during its circulation in the machine the reported slight wear on the impeller blades can be accounted account bd for by the slow speed of this appliance and while the feed is delivered directly over the air mats the resulting direction of travel from the centrifugal tri fugal force of the impellers and the air force through the mats causes the feed to ride above the mats not on them therefore the scouring of the fabric of the air mats is slight |