Hydrocyclone is a device to classify/separate or sort particles in a liquid suspension. The simple form is a cone, apex down, fed tangentially at the base. There are two exits on the axis the larger exit is on the base and a smaller exit is at the apex. Internally centrifugal force is countered by the resistance of the liquid, with the effect that larger or denser particles are transported to the wall and eventually exit at the apex with a limited amount of liquid, whilst the finer or less dense particles, remain in the liquid and exit at the base through a tube extending into the body of the cyclone.