Hello,

my name is Arne Lüken and I am studying process engineering in Hamburg Germany. In line with my studies I am working on a research about the phenomena of scale formation which occurs while transporting fluorated or secondary alumina with pneumatic dense phase conveying systems. Secondary Alumina originates in the dry scrubbing process, where fresh Alumina is used to adsorb the emissions from the off-gases of the electrolytic cells. For now it seems like the principle occurrence of scale formation is independent from the geographical location and the dense phase conveying system itself, whereat it does differ in speed of growth. Furthermore it seems that the Alumina itself is not the initiator of the problem, rather the fine dust or particle emissions seem to provoke the build up. Another interesting fact is that the incrustations increase at places of high turbulences (for example at bows and primary at the end of the conveying pipe due to higher velocities). Since this is a very particular problem I found it very hard to find any kind of literature or previous researches about this problem. Therefore I would be very pleased about any kind of information or knowledge like: Hints, Literature, Links, Contacts, Ideas, or Researches

(for example composition of the emissions, composition of the scale formation, or specifications of primary or secondary alumina, fundamentals about fouling or scaling build up etc.).

Thanks in advance for any leads.

Best regards

Arne Lüken ■