This paper describes a new development in the cyanidation of gold ores, which we expect will result in a major improvement in the way many gold ores are treated. The process has evolved through work at Hazen Research, Inc. for Kamyr, Inc. and in brief, the consists of utilizing oxygen rather than air in the … Read more
Because of the nature of the breakage in the Barmac vertical spindle impactor, the 80% reduction ratio is very small, so that when the energy efficiency is calculated by Bond’s method, it appears to be very low. However, the product size distribution contains a high proportion of fines. It is argued that the production of … Read more
An effective technique has been developed to elute ion exchange resins loaded in the carbonate leaching process for uranium recovery. The procedure involved elution with about 0.5 to 2 bed volume of 36.5 g/l. HCl, followed with 5 to 10 bed volume of acidic solution containing 3.65 g/l. HCl and 58.5 g/l. NaCl. This procedure … Read more
The flotation behaviors of pyrite and pyrrhotite in a Hallimond tube were correlated with the galvanic role they developed in two- and three-electrode combinations with mild steel under non-abrasive conditions. These correlations substantiated the hypothesis that a coating of iron hydroxides, originating from galvanic interactions, lowered the flotation responses of sulfide minerals. However, interactions between … Read more
This paper presents results of ongoing research to develop an in-situ leaching process for Michigan copper sulfide ores. The objectives of the work presented here were to determine if the copper sulfide was extractable by a bioleaching approach and to investigate how this process could be incorporated into an in-situ leaching operation. Laboratory Bioleaching Bacteria Selection … Read more
A selective dolomite flotation process has recently been developed at the University of Florida whereby a two stage conditioning technique is utilized to remove MgO impurities. Previous investigations have mainly involved studies on synthetic apatite/dolomite mixtures in a microflotation (Hallimond) cell. The collectors employed were of laboratory reagent grade and flotation was carried out in … Read more
The density of a Flocculant is usually evaluated by measuring its buoyant density while settling in a quiescent column. An equation of the general form (Matsumoto and Mori, 1975) is used to calculate the buoyant density (pa), from settling rate (U) and diameter of floc (Df). The constants Kf, α, β and γ depend on shape, porosity … Read more
The flotation of sylvite (KCl) and also some accessory minerals (e.g. kieserite, langbeinite) from crude potash salts are processes used to a large extent all over the world. These separations are made in brines which are in an approximate solubility equilibrium with the mineral phases of the crude potash salts and thus contain concentrations of … Read more
There was a continual increase in ball mill lubrication oil consumption. However, visual inspections could not confirm the presence of a trunnion oil seal leak. By the end of month it was assumed that the only possible place for this leak was at the outboard discharge trunnion seal so that oil was leaking into the … Read more
The Red Dog zinc/lead deposit in northwest Alaska is the second largest zinc deposit ever discovered. Being developed by Cominco Alaska with startup scheduled for early 1990, it will ultimately be the largest zinc mine in the Western World. Red Dog was discovered by a local bush pilot, Bob Baker, in 1968. The U.S. Geological … Read more