Chinese dairy giant partners with GEA for state-of-the-art infant formula plant in NZ

Yashili is one of the ‘big three’ producers of infant milk formula for the domestic market in China. A longstanding importer of New Zealand milk powder, the company has recently completed a $200 million, 30,000 m² manufacturing plant in Pokeno, 50 km south of Auckland.

With a production capacity of over 50,000 tons/year, the plant will supply the rapidly growing Chinese market and is a showcase facility that places special focus on innovation and on the hygienic design of the process plant and buildings.

GEA was chosen as the main process contractor, providing all the key elements: from milk and ingredients reception, to powder production, to final packing into 25 kg bags.

Process overview

• Milk is received at the Pokeno site and pre-treated. Ingredients are added using high shear mixing under vacuum. Vegetable oils, dry dairy powders, carbohydrates, vitamins and minerals can then be added directly to fresh milk. The resulting formulations are cooled in batches.
• The batches are further concentrated by removal of water under vacuum, using GEA tubular falling film evaporators.
• The milk concentrate from the evaporators is spray-dried in a GEA MSD dryer to produce a dry powder.
• GEA Avapac technology is used to pack the powder into 25 kg bags.

Innovation

The plant includes a number of innovative technologies designed to enhance product quality and consistency, reduce noise pollution and minimise the use of water and energy:

• Operations on 24-hour basis. GEA has designed the plant with multiple feed lines and duplicate up-stream systems (such as for evaporation) to allow continuous, 24-hour operations of the dryer. This facility increases output, helps ensure product consistency and avoids product quality problems associated with start-up and shutdown procedures.
• Built-in flexibility. As well as making infant formula from liquid milk, the Yashili plant can reconstitute milk powders for introduction as ingredients. This allows greater product flexibility and more accurate management of the milk supply.
• Inlet-air dehumidification. The GEA dryer uses dehumidified air and is one of the first spray dryers in New Zealand to benefit from this feature. By dehumidifying the inlet air it is possible to compensate for changes in humidity throughout the day or year, thereby optimising dryer efficiency and avoiding upsets in the drying process. It also ensures a greater consistency in the properties of the final powder.
• Water recovery. The water treatment system uses reverse osmosis to process water evaporated from the milk, which converts it into high-quality water for re-use within the plant. This reduces water consumption and minimises disposal costs.
• Exhaust heat recovery. A variety of best-in-class energy recovery techniques is used to recover waste heat and return it to the process. The high dryer-exhaust temperatures associated with the production of infant formula makes heat recovery both practical and cost-effective.
• Reduced noise. Special care has been taken to reduce noise from the plant, owing to its location near residential areas and its 24-hour operation. The building has been designed to contain noise, including the attenuation of noise at ventilation and process exhaust openings. Equipment is also strategically selected and located to minimise overall noise levels from the site.
• Advanced process control. Legislators, retailers and insurers are placing increasingly stringent demands on the traceability of food products: in particular, food for infants and the newborn. To meet these demands, GEA has included modules from its OTAS software suite for higher-level supervisory control of the Yashili plant. These modules ensure transparency in the production sequence, effective use of resources and high product quality. The GEA OTAS Track & Trace module allows Yashili full and transparent traceability of raw material and ingredient inputs, throughout the process and into the final product.

In addition to process innovations, GEA took on responsibility for all process buildings. This took place in conjunction with its partners Ebert Construction Ltd for the building work and Silvester Clark Ltd for building design. This partnership ensured high-level optimisation of building space to fully match process needs.