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Old 10-03-2008, 10:18 AM   #25 (permalink)
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Originally Posted by rmay635703 View Post
Sadly most farmers aren't that modern.


In terms of ethanol we should take the old slow method of malting, natural enzymes/yeast and WAITING. You can usually get away with not heating the mix in the summer months if you are willing to wait. We should not use fossil fuels to heat or distil. Sun dried Algae would make a great "heat" source burnt straight due to its oil content or any other biomass.
Maybe Colorado farmers are at the cutting edge, then.

It's the heat to distill that really takes up energy. Water and ethanol make a mixture that's hard to distill, and only so much energy can be reclaimed by heat exchange between incoming and outgoing product streams.

I think the sun-dried algae idea sounds pretty good. I wonder how long it would take at the typical relative humidity in the midwest? Maybe they could spin dry the algae first in a centrifuge.

I've read about experiments to replace distillation with other processes like reverse osmosis and zeolite filtration, but no one has claimed any commercial applications so far.

I was reading about a higher temperature, catalyst based, biomass to alcohol conversion that looks promising. I'll see if I can find the reference.

An advantage to using bacteria rather than yeast is that tailored bacteria can produce butanol instead of ethanol. Since butanol is only mildly soluble in water, it simply floats to the top. I wonder is a tailored yeast could go from sugars to butanol?
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