Anearobic Digestion of Sawdust, Wood Chips

Asked March 15, 2013, 10:04 AM EDT

I am trying to get an opinion on the feasibility of using wood waste, obtainable as, or reduceable to, wood chips or sawdust, in an anaerobic digestion process, to produce methane or other gases to generate electricity.

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1 Response

Great question. My experience in this arena is limited but I would wonder if the wood material would have nutrient value ( think nitrogen) to interest microbes enough to break it down in a time frame or speed one would need to make it feasible. So my next questions is do you have a nutrient source( animal or treated human waste) that could provide an enticing menu for the beasts to do the conversion work you hope for? My knowledge of successful digesters revolve around milking operations where rich nutrient waste drives the system. The one you propose is high on the carbon source but limited on the nitrogen side. Successful wood only systems that I know of revolve around placing a heating coil within a wood pile and extracting excess heat as the composting process is ongoing.A system you propose would need the perfect anerobic microbe that could accomplish the breakdown...perhaps if it could get energy from hydrogen sulfides or another chemical energy source you might be in business. Still look at through puts and yield and you will answer the feasibility question largely on your own ( eg low nutrient material....larger vessel....break down in days,weeks rather than hours = low yield & low probability of feasibility) Therefore heat or nutrients would be needed to speed things up to create a solution rather than add another problem. Hope this helped a little. Next step would be to seek out an expert on biological and agricultural engineering side for a consult.