Re: thumper distance to boiler
Ok, personally I think there's better ways of making booze than using thumpers. But if you want to go "traditional" for the sake of the experience (it's a part of the hobby that can be enjoyable) then check this out...
regards HarrySomeone else wrote:Many traditional Caribian potstills use the double thumper setup.
I've reasoned that they were left full from the previous run, and so should be full of mostly rum oil laden tails.
so I figure that modifying my still with this in mind should yield a better rum. Not sure what effect this will have on Grain spirits though, but I'm eager to give it a try.
something like this
I don't know if you've ever seen my sketch from several years back...
This shows the same as your pic, but gives the vital clues you need for processing.
First, the naming of the fractions (Jamaicans call them differently to us)...
High Wines = Heads
Low Wines = Tails
Seconds = Hearts
The feed pipes from the still and each thumper are submerged in liquid in the thumpers. This means that all the copper parts are pressure vessels. There is pressure in the system (due to the thumper liquid contents) right up to the final thumper exit. At this point there is no pressure into the condenser.
Water is plumbed to the condenser, the green shell & tube designed tank after the last thumper. Water is also plumbed to the red (rum), yellow (heads) & green (tails) receivers) and added as required to make up the ratios or percentages as indicated in the sketch. The sight guages and drain cocks on the receivers allow for accurate measurements and determining strengths.
Product flow exiting the condenser can be diverted to any of the receiver tanks via valves atop the receivers joined to the condenser exit line. All cuts are determined by the temperature of the vapors exiting the last thumper (see the dial-type pyrometer (aka thermometer)).
Preparing to Run:
Before a run, the thumpers are charged via the hand-pumps you see on the high wines & low wines receivers, enough water having been previously added to make up the ratios I show above; 50:50 low wines:water in the 1st thumper, 75:25 high wines:water in the 2nd thumper. Then the valves between the feints tanks and the thumpers are closed off.
Molasses beer of 8 to 10% is charged to the still. The still is fired (direct or steam. This one was probably direct fired in a brick kiln base). The beer charge is brought to boil and gives off steam. The steam is led through the two thumpers to the condenser where it is cooled and reverts to liquid.
The first runnings of the condenser (high wines or heads) are diverted to the now empty high wines tank. When the hearts (the "seconds") begin to run (determined by the pyrometer), they are diverted to the Rum receiver. At the onset of tails (pyrometer again), the flow is diverted to the empty low wines tank. High and low wines are kept for the next run. Then once again they are mixed with water to charge the thumpers for the new run.
(NOTE: Rafael Arroyo used a method whereby the tails were split again into 2 fractions. First fraction (cardboard taste) was discarded. Second fraction (rum oils, below 40%) was sent to the low wines tank.)
After a run, the spent thumper contents are drained to waste (see the grey drain valves at the base of the thumpers in your pic). The Rum is adjusted with water to the correct strength (85% a/v) and the keg/s are filled.
It's complicated, but it works. It's the difference between good rums and the insipid light stuff most hobbyists complain they are getting. Recycling the aromatics and congeners is the key.
You can find further info on Rum styles etc. in my folder...http://www.artisan-distiller.net/photoalbum/main.php?cmd=album&var1=Harrys_odds_and_ends/&var2=0
I hope you find this useful.