Rheology of Polymer Solutions
Viscosity measurement represents one of the simplest experimental techniques for characterizing polymers. In general, the viscosity of a polymer solution depends on the molecular weight of the polymer and on the configuration of the molecules. For essentially linear polymers such as the polyacrylamide flocculants, coiling of the molecule in response to changes in its environment […]
Continuous Thickening Theory
In a continuous thickener the downward solids velocity with respect to the thickener wall is the sum of the settling velocity of the solids by gravity alone, Vi, plus the downward velocity caused by removal of the thickener underflow, U. The rate at which solids move downward by gravity alone is expressed as the product […]
Polymer Adsorption
Adsorption measurements on all the solids were carried out by the methods described above. Figure 2 shows a typical isotherm for the adsorption of polymer A on coal. The adsorption density rises monotonically until an apparent plateau is reached. For the case shown in Figure 2, the plateau occurs at an adsorption density of about […]
Assaying Reagents
It is essential for the assayer to be assured of the fact that his reagents are pure, or at least to know to what extent they are impure and what the impurity consists of. For this reason it is necessary to examine lots of reagents from time to time, as they come into the laboratory, […]
Cyanide Safety
Cyanide Training Proper care and handling of Sodium Cyanide Why the need for training? To help ensure that Team Members are not exposed to harmful concentrations of cyanide through proper handling procedures. To assist all Team Members in understanding how cyanide is used safely and the environment is protected. To ensure all Team Members are […]
Slope Stability Determination Methods
Methods suitable for slopes in soil like materials, where the strength of the material can be determined from testing small specimens of the material in a laboratory. Classical soil mechanics slope stability analysis and material strength testing methods are applicable. Methods suitable for slopes in hard jointed rock where the stability of the slopes is […]
Vacuum Induction Melting
The effect of fluoride inclusions on the properties of titanium produced from the Bureau of Mines developed induction slag melting process is of concern to the titanium industry. The objective of the research was to determine the effect of removing the nonconductive molten calcium fluoride (CaF2) slag used as an insulator between the titanium and […]
Electrowinning Mercury in Gold Pregnant Solution
Many gold-bearing ores in the Western United States also contain small amounts of mercury. The presence of mercury creates potential pollution and health hazards during several steps in gold processing. An investigation was undertaken by the Bureau of Mines to develop techniques for removing mercury from cyanide mill solutions by selective electrowinning to reduce the […]
Secondary Copper Converter Dust Metal Recovery using Ammoniacal Carbonate Leaching
Effective recycling or disposal of flue dusts is a continuing problem, particularly for secondary smelters treating low-grade Cu scrap. The Bureau of Mines investigated a variety of flue dust treatment approaches and demonstrated the technical feasibility of a bench-scale alkaline method that includes leaching, cementation, precipitation, and roasting. Flue dust was leached at room temperature […]
Manganese Ore Leaching by Dissolved Sulphur Dioxide
The Bureau of Mines conducted column-leaching tests on 25 domestic Mn ores to determine the feasibility of extracting Mn by in situ or heap leaching with dissolved sulfur dioxide (SO2) solutions. The ores tested were obtained from deposits in Arizona, Arkansas, California, Colorado, Maine, Minnesota, Nevada, and South Dakota. Dissolved SO2 was found to be […]