IM 2019 IM May 19 | Page 19

MINERAL SEPARATION The air-pulsed alljig ® machines are physically stable in operation, allowing an optimum jigging stroke with minimum energy consumption, allmineral says The mineral separation company said it would supply two F/R type, single cut, side pulsed alljig ® units with enhanced shaft system and one M(UB) type, 2 cut, under pulsed alljig ® . The latter incorporated the company’s “state-of-the-art poppet valve system that significantly reduces air consumption”, allmineral said. “The M(UB) unit will furthermore be fitted with the allscan ® chamber monitoring system for the grains graded by density. The jigs end up separating the lighter yield from the heavier ore in the stratified material bed. “The air-pulsed alljig ® machines are physically stable in operation, allowing an optimum jigging stroke with minimum energy consumption,” the company said. “The jigging motion used to separate the particles is wear- free and induced by air, allowing the stroke motion (frequency, amplitude and shape) to be adjusted within a wide range of operating parameters. “Sensors are used on alljig ® systems to enhanced operation,” it said. Assembly and erection on site is expected this month. The patented alljig ® process sees feed material initially fluidised with pulsed water, with automatically monitor and control the discharge, with their signals captured and processed electronically. This allows the volume of heavy product fed into the jigging machine to be discharged with precision.” Round or rectangle? In density separation, Kwatani custom designs and manufactures a range of vibrating equipment to meet many feeding and screening requirements. Its individual machines can weigh less than a tonne or up to as much as 50 t and handle throughputs of 7,000 t/h of heavy metal ores. The South Africa-based company has a materials testing laboratory to assist with the selection of separation equipment. Here, materials are analysed, and tests conducted under simulated production conditions to help determine the appropriate machine size, optimum screen openings and machine settings for any given application. Kwatani has a number of rectangular and round separators suited to specific processing applications. The former has a horizontal gyratory motion that sifts, rather than forces material through the screen. This gentle action minimises screen tears from foreign objects, according to the company. Its round separators, meanwhile, feature a broad range of wet or dry, fine or coarse, heavy or light products and can be built up with as many as four screen decks for simultaneous separation into five fractions. Kwatani’s vibrating screens and feeders are continuing to find a market in the mining industry, with several orders recently secured MAY 2019 | International Mining 17