Flotation of uranium ores
Tinker, Edward Brian
In the past few years the potential value of Northern Saskatchewan's low grade uraninite ores has increased greatly. In April of 1950 the value of acceptable uranium concentrates was raised from $2.75 per pound of U3O8 to a maximum of $6.00 per pound of U3O8 (1). With the present emphasis on the development of nuclear energy as a source of commercial power, the value of these ores may be expected to increase still further. In the present work an attempt has been made to apply froth flotations as a means of beneficiating one of these low grade ores. From a consideration of the literature, it appears that at the present time, leaching is the most effective method of extracting uranium from its ores. However, leaching methods would probably become uneconomical if the grade of the ore were much below 0.10% U3O8. Since the discovery of major deposits of uranium ores in Northern Saskatchewan attempts have been made at the University of Saskatchewan to beneficiate low grade uraninite ores by notation (1, 2, 3, 4). These attempts met with little success except under conditions where the cost would probably be prohibitive. Flotation is today the most popular method for beneficiating ores. The cost of notation of sulfide ores based on 1940 prices ranges from 6.5 cents to 75 cents per ton of ore treated (5, p. 12,-101).The popularity of notation is due in part to its low cost relative to many ore dressing procedures. However, in plants where tabling is used as a step prior to flotation, tabling costs seem to range from one third to one-half of the flotation cost(5). While successful tabling is dependent on a large difference in the densities of the minerals fed, separation by flotation is independent of density (6). In conducting the flotation research at the University of Saskatchewan, flotation has been regarded as a preliminary step to leaching. The emphasis has been on the achievement of high recoveries at the expense of concentrate grade. Much of the previous work at this university consisted of attempts to find a suitable collector for the uraninite in these ores. In the present work considerable attention has been directed towards the method of carrying out the flotation tests as well as to the search for a suitable collector. Several reagents have been found which seem to exhibit some degree of selectivity towards uraninite in the flotation process. In the present work the effect of variables such as pH, as well as the effect of the type of reagent used, have been investigated. As in the previous work, this investigation has been carried out with a view to obtaining high recoveries of uraninite in the concentrate. High concentrate grades have been of secondary interest. Numbers in brackets refer to bibliography.