Originally By Tony Ackland

## Column Height properties in Reflux Still's

So, put these together to work out your still performance;

• Determine the HETP for the packing you are using, then
• Work out for the height of packing you have, how many Ideal Plates you have, then
• Look up the purity expected for that number of plates.

SS = Stainless Steel Wool Scrubbers, RR6 = 6mm Ceramic Raschig Rings,
RR13 = 13mm Ceramic Raschig Rings, M = 10mm Marbles

But what diameter should the column be ? This needs to be worked out from the amount of heat you are putting in. The more heat, the more vapour you generate. If the vapour rate is too great, then instead of having your refluxing liquid flowing down the column, it will be blown out the top. You also need to consider how much space the packing is taking up too. The following diagram is based on the calculations - unfortunately the sizes are about 50% smaller than what appears the actual limit, so scale up the calculated result if you plan on following them.