Tertiary recycling, defined

Cone crushers are increasingly being used as secondary and tertiary crushers and are frequently operated in closed circuit (i.e. with over-sized particles being screened out and recycled to the crusher) to produce a well-defined top size, with minimum fines. They have similar reduction ratios to gyratory crushers (4 1 up to 6 1) and produce a more slabby product than impactors. 

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