At Bougainville Copper Limited comparison testwork was conducted between "horizontal" cycloning and conventional vertical cycloning._x000D_
Horizontal cycloning reduces circulating load and allows increased ball mill throughput. Cyclone efficiency is the same or better as a result of the reduction of fines short-circuiting to the underflow. Operationally, horizontal cyclones are less likely to suffer from blocked spigots and high cyclone feed pump sump levels. Cyclone feed pumping power is reduced._x000D_
High horizontal cyclone underflow density provides the option to optimise grind by manipulating water addition to the ball mill feed.