Powder Technology, Vol.208, No.2, 378-382, 2011
Dry particle high coating of biopowders: An energy approach
The general aim of this paper is to study the coating strength of different composite powders with an experimental approach based on mixing energy descriptors derived from linear velocity at the end of paddles. The chosen system is Cellets particles coated with Talc particles, with two size ratios: 7 and 22. The studied processes are Nara Hybridizer NHS-0, 1 litre Hosokawa Cyclomix, Turbula mixer and finally "Basic Mixing". The developed energy analysis leads to quantitative comparison of the equipment and helps to show the specific dry coating improvement in term of coating strength compared to the simple ordered mixing phenomenon. According to the chosen energy descriptors, in accordance with the litterature, the Hybridizer is the higher energy system and leads with the chosen operating conditions to the stronger coating. If we compare the other processes, the increase of mixing energy always leads to an increase of coating strength as soon as breakage is avoided. This can be possible by choosing the adapted operating parameters in each system. (C) 2010 Elsevier B.V. All rights reserved.