Tetra Pak Bulkpak 600 Postgasser - Heat Sealer for bulk bags

To reduce or eliminate product deterioration and prolong the shelf life of fat-containing dairy powders, it is important to close bulk bags immediately after filling to minimise exposure of the powder to atmospheric air. Historically known as Bulkpak 600, the Postgasser - Heat Sealer by Tetra Pak is designed for powder deaeration and replacement of ambient air with an inert gas, followed by hygienic closing of the bulk bags.

The Bulkpak 600 comprises a single station capable of handling a wide range of plastic liners suitable for modified atmosphere packaging (MAP) and heat sealing. To minimise exposure of the powder surface to atmospheric air, the heat sealer would be usually located in the immediate vicinity of a filling station.

The filled bulk bag is conveyed to the Bulkpak 600, where the operator puts the plastic bag liner onto the heat sealer bars and secures both ends of the liner with the assistance of pneumatic bag grippers. Once the cycle has been initiated by the operator, postgasser probes go down into the powder and replace ambient air with an inert gas, such as nitrogen.

This achieves residual oxygen levels typically under 3% after seven days from closing. Optionally, the operator can perform selected stages of the cycle, such as only deaeration or only heat sealing. All stages of the cycle are timed and automated. An extensive range of testing and indication features provide the operator with comprehensive feedback on process flow at each step of the cycle.