bluc wrote:Probably a dumb question but what is spp?
Not a silly question at all, SPP spiral prismatic packing is used in a reflux still in place of the stainless steel pot scrubbers commonly used by home distillers. It is like thousands of very tiny stainless springs about 5mm x 4mm with almost square corners rather than a continuous spiral.
It when used correctly far more efficient than scrubbers. End result is much much faster takeoff still at 95%+ purity. I can get 100ml in 4 minutes easily, more of a slow stream than a drip
It's harder to get hold of or make so it's often very expensive, mine came from Poland.
The application it was developed for was heavy water production by the Soviet Union during the cold war but since the size and shape has been perfected for alcohol distilling. Will try to find some good links to information about it.