scope:

These 3-A Accepted Practices shall pertain to the sanitary aspects of equipment for spray drying milk and milk products, and include all equipment necessary for spray drying milk and milk products beginning with the discharge of the final pump which delivers the liquid product to the atomizers and terminates at the point the finished product leaves the system for conveying either to the packaging system or to bulk storage. The drying system may include but shall not be limited to the equipment used for moving and cleaning air, heating and/or cooling air, fluid product handling, fluid product heating, fluid product atomizing, gas injection into the product, atomized product dispersion into the heated air, dry ingredient introduction into the process air or product, product reintroduction, agglomeration, dry or partially dry product retention, additional product drying, separating dry product from the air, exhausting the air, dry product cooling and/or conveying, dry product sifting and classifying, dry product particle size reduction, metallic particle detection and separation, internal vibration, air locks, fire suppression appurtenances, pressure relief (explosion venting), product sampling, heat recovery, permanently installed mechanical cleaning devices, instrument sensor fittings, observation ports and any other equipment that may become a part of the spray drying system for handling processing air or product.

Pneumatic and/or mechanical conveyors which are an integral part of a spray drying system are subject to the same material, fabrication, design, and processing air requirements of 3-A Sanitary Standards for Pneumatic Conveyors for Dry Milk and Dry Milk Products, Number 39- and 3-A Sanitary Standards for Mechanical Conveyors for Dry Milk and Dry Milk Products, Number 41- both of which apply to such conveyors that are not an integral part of a dryer system.

In order to conform to these 3-A Accepted Practices, spray drying system components shall conform to the following criteria for design, material, fabrication, air supply and the applicable documents referenced herein.¹

¹ Use current revisions or editions of all referenced documents cited herein.