Bulk storage silo for Westland Dairy

Westland Dairy has engaged Mercer Stainless to build a new bulk storage silo for raw milk. The silo has a working capacity of 300 m³.

With increasing demand across the world, Westland Dairy required additional storage for raw milk to even out delivery for processing. The new silo required ø 4500 mm dome base which is self-supporting and manufactured out of 10 mm 304-grade stainless steel to ensure the raw milk was held in a hygienic and sanitised condition.

Having an overall height of just less than 23 m, the silo features a fully automated spray ball clean-in-place unit which cleans the silo, vent and overflow once empty, ensuring the silo is clean for the next fill. This is accessed by the incorporated platforms and access ladders which are designed as an integral part of the silo. The access ladder also provides access to the manway approximately half way up the silo, which allows access to the agitators that are located there and at ground level.

The silo was insulated using 50 mm polystyrene skin and then cooled using a 60 kW refrigeration unit fitted to the bottom strake. After vacuum testing, the refrigeration dimple pads were charged with nitrogen and are capable of cooling 150 m³ of milk by 1°C every six hours.