FEATURE
Flotation reagents in the mineral processing industry
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lotation is the most flexible and adaptable mineral beneficiation technique. Mineral separation by flotation works on physicochemical surface properties of valuable and unwanted gangue minerals. It is being continuously modified for low-grade complex sulfide ores like lead-zinc, leadzinc-copper, nickel-platinum-gold, tin, fluorite, phosphate, fine coal and iron ore at a lower cost with better recovery. The processes are known as froth and column flotation. Froth flotation Froth flotation process produces froth of selective mineral agglomerates and separates them from other associated metallic components and gangue minerals. The physicochemical surface properties of optimum fine size fraction make some specific minerals hydrophobic. The particles turn into water repellent by coming in contact with moving air bubbles in the presence
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of certain reagents. The forth portion moves up leaving other metallic minerals and gangue (tailing) below, stabilizes for a while and collects as concentrate for further cleaning. The mineralized concentrate stabilizes for a while at the top of the cell, overflows and moves to cleaner, filter and dryer in sequence to form mature salable product. The concentrate is the raw material for extracting metals by smelting and electro and chemical refining. There are three main types of reagents used in flotation, namely, collectors, frothers and regulators. Each individual set of reagents plays a specific role in mineral processing. Collectors, also known as “promoters�, are organic compounds which make the surface of certain selected minerals water repellent. These reagents are added to the pulp in the conditioner tank and ball mill. The mineral surface
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