Abschnitt 7.3 - 7.3 Removal of flour from the silo
The various methods for delivering flour from the silo into the bakery include vacuum, pneumatic and spiral conveyor systems. Regarding vacuum systems, the conveyed air is returned to the silo installation or chamber, so that the breathing air is not contaminated with flour dust.
Where pneumatic systems are used, they must be operated in such a way that they generate a minimal amount of dust. In these systems, the conveyed air leaves the flour scale through a filter cloth and enters the atmosphere in the bakery. Leaks in the installation or the filter cloth can increase the level of flour dust in the breathing zone close to the flour scale. Therefore the area above the flour scale has to be inspected and cleaned regularly. If leaks are detected, they must be eliminated immediately. Filter systems with automatic cleaning do not require a filter cloth.