Chemistry of Slurry Rheology Control by Grinding Aids
Tests run on using organics to influence the fracture strength of solids gave an almost bewildering array of results on the four substrates. Two general classes of tests were carried out: 1) a procedure consisting of introducing a notch in a small rectangular sample, placing this sample in an environmentally controlled chamber for humidity, chemical […]
Flocculation & Lewis Acid-Base Theory
The use of synthetic polymers such as polyacrylamide and its derivatives to dewater mineral-processing waste streams has become commonplace. The use of polymers often solve many of the solid-liquid separation problems encountered by the industry. However, using polyacrylamides to dewater clay containing minerals such as montmorillonite and kaolin often produces a dewatered material containing a […]
Hydrocyclone Modelling Method
Mineral and chemical industries use the hydrocyclone for size classification as well as solid-liquid separation. The geometry of the device being very simple, a tangential involute section attached to a cylindrical section and a conical section attached to the other end of the cylinder, the device has found widespread use. Majority of the research papers […]
Agitative Agglomeration
Agitative agglomeration is the process of the consolidation of particles into larger shapes by means of agitation with a liquid. Most fine powders can readily be formed into granular masses by admixture with a liquid and by utilizing a suitable agitation method. Ideally, each particle should be coated with the liquid by stirring or moving […]
Thionocarbamates Collector & Sulfide Flotation & Adsorption
The mineral processing industry has recently shown an interest in developing new collectors that can be used for selective flotation at lower pH levels. The desired end result is to reduce lime consumption and to improve the efficiency of separation in the treatment of complex and low-grade ores (Nagaraj et al., 1986c). One such reagent, […]
SABC Grinding Circuit
Brief Geology in Relation to Work Index Variation To understand the need for a SABC Grinding Circuit it is pertinent to briefly describe the geology. Gold mineralisation at Kidston occurs in the marginal areas of an oval breccia pipe. Gold and silver are disseminated within the breccias and veins formed after brecciation. The ore is […]
Thickener Operation and Flocculant Application
At start-up, the relatively high level of feed solids, 17-20%, called for in design led to difficulties in achieving the degree of flocculation necessary to meet required settling rates. It was recognized that decreasing feed solids would improve thickener performance while reducing flocculant consumption (Figure 2). This was accomplished by recycling thickener overflow to the feed […]
Estimating Weak Rock Strength
Factors Controlling the Strength of Weak Rock Masses: For the purposes of this paper a weak rock mass is defined as any rock mass in which the effective shear strength parameters are less than: effective cohesion, c’ = 25 psi (0.2 Mpa) effective friction angle, ∅’ = 30° using the Mohr Coulomb failure criticism. This would […]
Kinetics of Sulfuric Acid Leaching of Brass
Effect of Temperature and Acid Concentration: The effect of temperature on the leaching behavior of copper and zinc is shown by the data in Figures 1 through 4. In these experiments, leaching solutions were well stirred at 550 rpm and open to air. “Fraction Extracted” refer to that portion of the total copper and zinc that […]
Carbon in Leach with Oxygen CILO Process for Gold Ores
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 […]