Dairy & Beveragesfor heat and moisture sensitive powders.

Spray-dried dairy powders sit close to a physical edge. Lactose in an amorphous state has a glass transition that falls sharply as the powder picks up moisture, so a small rise in ambient humidity can turn a free-flowing powder sticky. Once it is sticky it plates onto pipe walls and vessel surfaces, builds up, bakes, and eventually releases as a discoloured lump that shows up as a scorched particle at final inspection. The engineering answer is to keep the powder cold and dry in transit: dehumidified conveying air, insulation or lagging where lines pass through hot areas, no dead legs where material can sit, and routes short enough that residence time stays low.

The second constraint is particle integrity. Instant powders are agglomerated deliberately — the loose, porous cluster is what makes them wet out and dissolve instead of floating as a raft. A high-velocity dilute-phase line grinds those clusters back to fines, and the customer finds out at the point of use, not on the QC bench. Dense phase moving material as slow slugs, generous long-radius bends, and controlled acceleration at the pickup point all protect the structure that was expensive to create in the dryer.

Infant formula raises the bar again on segregation and traceability. Minor ingredients — vitamins, minerals, trace nutrients — are dosed in small masses against tight tolerance, so weighing resolution and dosing repeatability matter more than throughput, and the whole batch record has to reconcile. Cleaning is validated rather than visual, and the line is designed so a wet-cleaned section can be dried completely before powder returns, because residual moisture in a dairy line is a microbiological problem as well as a flow problem.

Around all of that sits ordinary bulk handling: road tanker or bulker intake, silo storage with the right discharge aid for a cohesive powder, sieving and grading before and after processing, and dust collection that keeps a fine, light, valuable powder out of the building. Milk powder is expensive enough that collected fines are worth recovering into the process rather than discarding — provided the recovery route is as hygienic as the main line.