GB471683A - Improvements relating to froth flotation cells - Google Patents

Abstract

471,683. Flotation apparatus. CALLOW, J. M. (General Engineering Co., Inc.) March 6, 1936, No. 6829. [Class 82 (ii)] A froth flotation cell comprises a rotating gas disseminating device, e.g. a disc, means to introduce gas into the pulp at a point below the device, and baffles arranged so as to extend into but only partly to bridge the space between the cell walls and the edge of the device. The baffles are preferably mounted on or formed integral with supports disposed on the bottom of the cell or liners for the cell walls. The combined liners or base supports and baffles may be made in sections which may interlock. Fig. 2 shows a tank divided by partitions 5 into a plurality of cells 7, 8, 9, 10, each comprising an air-distributer 24 and a rotating disc 23. The baffles 30 are radially arranged at the ends of the tank and are perpendicular to the walls along the sides. In an alternative arrangement the baffles are radially disposed round the disc in each cell. Figs. 4, 5 and 5a show various arrangements of combined baffles 30 and wall liners 35, these being made either in fiat sections 33 or corner sections 32. The space between the corner sections and the cell walls is preferably filled in with triangularly shaped blocks 37, e.g. of wood, the upper surfaces of which are sloped towards the corners. The end liners are cut away as shown at 13 and 14, Fig. 5, to allow entry and exit of the pulp. The combined supports and baffles may be made of wood, welded or cast metal, moulded plastic material, &c. The air distributer may, as shown in Fig. 7, comprise a body portion 40, which fits into a hole in the cell bottom and is secured by a flange 41, and a member 42 with recess which is covered by a perforated medium 44 such as canvas or rubber. Alternatively, a hole in the cell bottom may be covered with the perforated medium and a manifold secured to the underside, or the air may be supplied by a pipe passing through the cell bottom, the top of the pipe being provided with a flap valve. In the form shown in Fig. 9, the air is supplied by a pipe 54 to a member 53 which is provided with bearings and stuffing boxes and in which is mounted the rotating shaft 20, which is hollow and has an aperture 55 to admit the air, and carries on its lower end the gas disseminating disc 23. The disc, which may be either blank or perforated, has a central aperture so that the air passes to its underside. The disc may be of rubber reinforced with a flexible medium such as canvas or, as shown in Fig. 10 may, when the air is supplied through the shaft be formed as a flat member with a recess 57 in its under portion which is covered by a perforated medium 57<1> of rubber or canvas secured by a grid or spider 58. The air passes through a hole 59 and through the perforated medium into the pulp.