A single- or multicore spiral separator in the bypass separates anything round from anything non-round. The spiral separator operates by gravity and requires no power or maintenance.
View of material flow: Material is loaded into the hopper at the top of the spiral separator. The material then flows over a cone and divides the material evenly onto the inner flights. With increasing speed the round material will separate and roll off the inner flights onto a larger outer flight and then exits a side discharge chute at the bottom and drops into another elevator.
The non-round material on the inner flights will exit a centre discharge chute at the bottom. This material is collected as waste.