Please note: Do this at your own risk. Do not leave unattended while boiling water in a PC (not your computer)
Buy two pressure cookers
(store the pot of one; you can use it later) Keep one top in original condition for cooking
your pot roast. With the other lid, drill and tap for a 1/8 NPT for a 1/4" x 1/8" tube/MIP brass angle valve (drill hole at least 2" from any other hole). Add 4' - 1/4" ID x 7/16” OD crush-resistant, high temp. silicone tubing. Add 4' 1/4" soft (annealed) copper tubing (coiled 3" dia. use 24OZ beer
can to wrap[drink beer
later]) leave approx 1 foot straight to collector (beer can after you drink the beer). (By the way clamp everything) Add water to the pot, add heat to the pot and presto (no pun intended) you have fresh water from turds or even brine. There's no need to cool the condenser coil, but you can put it in a bucket of cold water if you like (makes things go faster). Remember, water flows downhill (unless you live on a boat), so put the collector on the sole. Optional safety
would be to add chlorine or iodine; amounts vary depending on manufacturers of these product, so follow their instructions.
Do not boil dry, you'll have to throw it away (the pot not the boat).