Meanwhile, this PDF on commercial BioGas points out the relatively high temperatures (55 C or 131 F) required for the most efficient gas generation. [url=http://www.energymanager.eu/getResource/10018/biogas.pdf]www.energymanager.eu/getResource/10018/biogas.pdf
To tie two popular technologies together here, does anybody think a RMH could be utilized to speed up gas production?
I could also see how a heating and cooling cycle of an intermittent RMH might help to keep the soup mixed.
I thought biogas was interesting too.... till I read the part about daily attention (different site). I like to go on holidays or forget once in a while. Animals are the same, but it is more possible to get your neighbour to do your animals than your methane... unless they have a similar system.... Something to remember though for the time when nobody does holidays anymore cause there aint no gas for the truck.
Not saying it's a bad idea, it's a great idea if it can be fit with your life style and set up. I'm urban so no animals to produce feed(dog and family not included) and not enough veg matter to be workable. using the gas would mean adding a second kitchen at least at first as I don't think we would have enough gas to go bio only. Wood makes more sense to add to our heating and cooking.
Batch would be a great first try and would tell you if you want to deal with the problems. If you have a covered porch or patio and can put in a convertible BBQ (gas/propane) as an outdoor kitchen for trying it out it wouldn't matter if you only produced in summer. If that works out, then running part of the RMH exhaust might be something to try for the winter. Any recommendations I have heard are to run the digester at a distance from the house... another complication. Compost heating might make more sense.
If your doing a batch system instead of a continuous flow system, you only fill the digester tank about once a month. Also, as long as the tank is well insulated, one can use a fraction of the methane produced to maintain the optimal temps. For a convienient methane calculator, check out http://biorealis.com/wwwroot/digester_revised.html
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