New Tall Form Spray Dryer

‘Butter is back.’ Agri-Mark, the farmer-owned cooperative based in Andover, MA, needed to expand capacity. Consumer demands for butter left their West Springfield plant with a surfeit of skim milk, the by-product left behind after skimming cream from milk provided by local dairy farms. Expanding with a tall form spray dryer would allow Agri-Mark to turn greater amounts of the leftover skim milk into milk powder, which offers a longer product shelf life.

Dennis Group designed and built the necessary expansion adjacent to the existing plant: an RO, TVR finishing evaporator and tall form spray dryer to USDA standards for NFDM, MPC and buttermilk. Agri-Mark receives whole milk. Cream can be separated and pasteurized for butter production or loadout.  Whole milk, skim or buttermilk is then pasteurized and fed to an RO membrane system used to concentrate the single strength milk to approximately 32-33% solids. A falling film TVR evaporator further concentrates the milk to 47% solids. As the final stage, the product is concentrated to 97% solids using a vertical spray dryer with an indirect burner.

Multiple dryer technologies/geometries were evaluated in the design phase. The process included a final fluidized bed dryer with an equilibrating and cooling system. Overall powder capacity is approximately 4,000 LB/HR. With the expansion of the drying equipment, the plant’s capacity has grown from 1.6 million gallons of milk a week to the ability to take in 2.3 million gallons a week.