GEA Niro's Lactose Production Process

GEA Niro and it's affiliated companies in the GEA Group offer a wide range of technologies for the refining of whey into lactose powder. Niro's process engineering expertise in delivering production plants for dairy makes us perfectly suited to be your technology partner for Lactose production. Our focus is always on delivering a technologically superior solution for the lowest capital and operating cost.

The dry solids in whey are mainly lactose, proteins and minerals. The different compounds are used as ingredients in Infant Formula, health products, functional foods and pharmaceuticals. Lactose is the largest portion of the whey solids and can be easily separated and refined.

Lactose processing involves Evaporation, Crystallization, Mechanical Separation, further purification and Drying in a specially designed Niro Fluid Bed Dryer.

Niro Lactose Dryers

The first step in refining Lactose is to have either whole whey or whey permeate from Ultrafiltration concentrated in an evaporator or in combination with RO Filtration and evaporator and fed into crystallization tanks where a very controlled cooling regimen is employed to develop lactose crystals at a maximum yield.

Prior to the Evaporation step, it is possible to precipitate the calcium from the whey or permeate and harvest it both as a nutritional supplement product stream and to increase the run times of the Lactose Production Line.

Whey or whey permeate concentrate from the crystallization tanks is then passed through a decanter, where the main portion of the lactose crystals is separated. The crystals are then washed in order to remove residuals of mother liquor, after which it is dried in a specially designed Niro fluid bed. The fluid bed is divided into three sections. The first section is a stationary back-mix bed into which the wet crystals with 8% moisture are fed by a rotating disc. To avoid lump formations this section is equipped with a rotating rake. From the back-mix section the powder enters the plug-flow fluid bed section for the final drying. Hot air of about 210°C is used for the drying.

The average crystal size (200-250μ) is of importance for the fluidization velocity that can be used. Crystal size influences the performance of the fluid bed, as smaller crystals would require lower fluidization velocity, or too large of a carry-over of product to the bag filter would be the result. A Pre-crystallization step of 48 hours is used to "grow" the size of lactose crystals.

From the second drying section the powder enters the cooling section which like the last drying section is designed as a plug-flow fluid bed. The air used for cooling should be dehumidified. All the exhaust air is passed through a bag filter for separation of fines, which are returned to the back-mix section. Lactose produced this way is termed crude lactose. A more refined type pharmaceutical lactose - is produced by redissolving the washed crystals from above mentioned decanter and then crystallizing a second time by cooling followed by another decanting/washing prior to the final fluid bed drying.

The drying air that exhausts from the fluid bed will be drawn through one Niro Bagfilter to be exhausted from the plant and will meet the most stringent environmental standards.

The Lactose powder exiting the fluid bed dryer is very often classified with different crystal sizes. Milling of the powder after the fluid bed and final sifting is often required.

Finally, the finished lactose powder, either milled or course, can be conveyed to storage Silos and packaged into 50lb/25kg bags using our line of Avalon (now GEA Avapac) Packaging Equipment or packaged into Bulk Bags.

Niro can supply a complete Lactose Process solution for your production plant including integral CIP capability and Process Control Systems to provide exact control of all operations. Our project service expertise includes Project Management, Custom Equipment Engineering and Design, Equipment Manufacturing and Delivery, Installation and Commissioning and a full line of After-Market Service Programs.