As a though to cost savings. Has anyone tried a PG/PGA 50/50 heat extraction or a 25PG/75PGA extraction? I was thinking of trying a 25PG/75PGA extraction. I figure after a 75% reduction you would have a 75% reduced PG extract while saving 25% on your PGA bill. Any thoughts?
My only concern would be how well the sediment and oils would settle during the cold freeze.
I've read the process on recovering the alcohol but as of yet I'm not ready to make the purchases required to do this as far as finances go.
Thus far I've done 8 extractions and they all turned out great. Thank you all for the support and knowledge you've provided.
I've experimented extensively with PGA/PG solvent blends at various mix ratios for both hot and cold extractions. Personally, I observed no benefits from doing so but YMMV. You can't freeze filter PG, so any oil, wax and resin leeched during the extraction process stays in the extract rendering it as gunky as a traditional NET. I don't know at what mix ratio PG would negate PGA's freeze filtering attributes, perhaps a small percentage would have minimal impact.
For the "ultimate" cost savings when using PGA (
Ethanol), the reduction should be made by vacuum distilling the extract where you recover the PGA that is removed and can re-use it again and again. Because of Ethanol's low boiling point (
173F), vacuum distillation is easily achieved by heating the extract to 140F and applying a light vacuum. Vacuum distillation provides a second benefit, it purifies/concentrates the ethanol. If I lived in a country where the strongest alcohol legally available was 100 proof Vodka (~50% ethanol, ~50% water), vacuum distillation can convert it to 95% ethanol, like the PGA we use. The process is known as "fractional distillation", an intimidating technical term for a process that's quite easy to accomplish. A crock pot, two modified canning jars, a $22 vacuum pump and a $30 Liebig condenser is basically all you need.