Pumping transfers the ore and concentrate slurries from one phase to another in the concentration plant. The sludge is pumped by horizontal or vertical centrifugal pumps.

Outokumpu’s old concentration plant, which began operations in 1928, was built on a steep slope. The concentration plant on the slope took advantage of natural height differences so that the ore lifted from the mine flowed from one process to another by its own weight. It was intended to reduce the need for pumping.