FEATURE
Flotation reagents in the
mineral processing industry
Flotation 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 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
14 www . fmdrc-Zambia . com