Alright, just got all the parts for my BD processor today and im working on trying to get a dry wash system going. Ive been reading about people using wood chips and would like some more info on this method. Does any hardwood work? Does it remove the methanol or will i have to demeth? How much wood chips would i need to filter 40 gallons of BD? What rate does the wood chip method efficently wash at? Looking forward to good smelling exhaust!!
There's currently an active thread on drywashing with wood chips, and tons more information. Quite a few members there are leaders in homebrewed bio and the site has some of the latest advancements around. I wish to stop water washing and would like to go to a wood chip system, but I have a lot more research to do.
Wood chips work great but will not clean to astm. Wood chips work best for soap. You will need to demeth. The best way would be to use a 55 gallon drum almost full because wood will float. in flow on top out in the botom. Any hard wood will work. They say oak is very good. You will also need to get the sap out before using them. Fill your drum with methanol and let sit for a day. Drain and do again. You can still use the methanol for reactions. You will need to air dry the chips or run BD through untill free of methanol. I cannot remember the flow rate but it is slow. 5-10 gph. I still would use a resin for the final polish to get the glycerin. Most the soap will be in the wood so the resin will last longer.