Transport Processes and Separation Process Principles (Includes Unit Operations) Fourth Edition

14.5. MECHANICAL SIZE REDUCTION

14.5A. Introduction

Many solid materials occur in sizes that are too large to be used and must be reduced. Often the solids are reduced in size so that the separation of various ingredients can be carried out. In general, the terms crushing and grinding are used to signify the subdividing of large solid particles into smaller particles.

In the food-processing industry, a large number of food products are subjected to size reduction. Roller mills are used to grind wheat and rye to flour and to grind corn. Soybeans are rolled, pressed, and ground to produce oil and flour. Hammer mills are often used to produce potato flour, tapioca, and other flours. Sugar is ground to a finer product.

Grinding operations are very ...