I decided yesterday to follow some advice from "Uncle h" on the VOD and undertake a double or 2 stage glyc wash in an attempt to lower the amount of ASM I currently use. I never managed to use less than about 3.3-3.5lt to convert a 150lt batch.
My first wash was with the used glyc wash from 2 batches ago and I blended this for about an hour. Settled and drained I then added the unused and meth/catalyst rich glyc from my last batch. Uncle h has stated that he can get a pre conversion of between 10-25% using this method. Having performed a 10/90 I found a conversion of 0%....very disappointing.
I usually use 3lt (150 x 4 x 5) of ASM for stage 1 and typically get 10% unconverted, but this time decided on 2.3lt plus 18lt of methanol. The unconverted worked out at 20%.
Stage 2 shortfall worked out at 600ml of ASM plus 3lts of methanol. This went to full and instant 5/45.
Conclusion:
This method seems to work....a saving of approx 500ml of ASM. I can only assume that it would work better with a bigger pump or an eductor fitted to the plant. I'll be giving this method another go when I next make fuel.