Summary: | Includes bibliographical references. === The flotation process is used in extractive metallurgy to concentrate the mineral contents of ores by 'floating' the mineral particles out of an ore pulp with air bubbles. The pulp consists of finely ground ore, water and reagents, whose purpose is to make the mineral particles attach themselves to the air bubbles passing through the liquid. These bubbles reach the surface of the pulp and form a layer of froth, containing the ore concentrate, which is skimmed off for further processing. In order to optimise the process, it is necessary to have a reliable method o of monitoring liquid level in the flotation cell. The presence of the flotation froth complicates this measurement as it obscures the surface from visual observation and clogs conventional mechanical level measurement systems. The presence of air bubbles in the pulp and foam, makes acoustic systems equally unsuitable due to attenuation effects. The absence of a microwave system for level measurement in flotation cells led to the proposal of this thesis. It is therefore concerned with investigating the feasibility of using a microwave level measurement system for automatic liquid level control in flotation cells.
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