Using Flotation on Copper Sulfide Ores

Because of the distinctly different types of reagents used for the flotation of sulfide and non-sulfide minerals, it is convenient to consider these two groups of ores separately. The metal sulfides and native metals are substantially all floatable with xanthate and other similar collectors. The types of reagent combinations and some of the flow sheets used on the more common sulfide mineral ores are discussed in this section.

The largest flotation concentrators in the world are those treating copper ores. In may of these mills, the various copper sulfide minerals, as well as native copper and oxidized or specialty collectors. Such flotation is generally conducted in a pulp made alkaline with lime to a pH from 8.5 to 12.5.

Since the sulfide copper ores generally contain appreciable quantities of pyrite, the principal problem is to secure the differential flotation of the copper while preventing excessive iron flotation. The degree of iron depression accomplished will depend on the association of the copper and iron the ore. If there minerals are substantially liberated from each other at relatively coarse grind, a simple flow sheet, as shown in Figure 5 (a), may be satisfactory. This is the conventional and straight forward “rougher” flotation with single stage cleaning of the rougher concentrate.