Solids

Solids are particles whose shape and volume are fixed, unaffected by the space available to them, and which tend to resist forces that would alter their shape. In food the category spans powders, granules, crystals, and whole pieces such as fruits and grains. Handling solids in plants means managing flow, segregation, and dust: equipment such as cyclones separates food powders from air streams by spinning the mixture so particles are flung to the chamber walls and drop out, while the cleaned air exits centrally. Preventing caking, moisture uptake, dust explosions, and cross-contamination between batches are the everyday engineering concerns of solids handling.