Mineral processing: flotation, physical separations, environmental

点击翻译按钮获取中文摘要

Society has always needed mineral resources, both as commodities themselves, such as talc, and as sources of metals such as nickel. The extraction of minerals involves size reduction of mined rock (ore) and separation of minerals, together known as 'mineral processing'. Given Canada's abundant natural resources, mineral processing is practiced on a huge scale, billions of tons of ore annually, and thus process improvements can realize large benefits, economic and environmental. The importance to Canada is recognized in the series of industry-sponsored grants starting in 1991 of which this is the latest. There are seven companies supporting this grant directed at improvements in aspects of mineral processing: flotation, physical separations and environmental. Flotation is a mineral separation process that relies on creating large numbers (swarms) of small bubbles (ca. 1 mm) to collect ('float') selected mineral particles suspended in water. Swarm properties are controlled by chemicals, deliberately added in the case of frothers or naturally occurring, as in processing oil sands. The action of these chemicals, still not understood which hampers their effective use, is a focus of this grant. Our sustained emphasis on bubble swarm properties has realized important benefits and the current studies hold additional promise. Physical separations refer to processes that exploit mineral properties such as magnetism and density. A new tool to track particles in real time in separation devices is revealing insights that will lead to enhanced performance. The group is the only one in Canada with this technology. Trying to reduce water usage dry physical separations are emphasized. Last, but never least, the environment topics cover metal recovery from dilute effluents, and safe transport of sulphide mineral products which can spontaneously heat. The group has unique facilities for the study of spontaneous heating which are routinely accessed by the sponsors.