Hey all you chemists of the STMB. I know if I have an Idea usually a few dozen smarter people have already had it and discounted it.
That said, I know that one of the reasons ethenol is not viable as a fuel is that it takes more energy to make it than it provides. Then it hit me, alcohol freezes at a lower temp than water does and corn is generally grown in areas that freeze pretty hard in the winter.
My idea is; ferment the corn sludge in the summer when it is nice and warm, then when winter comes let it freeze up and scoop the slush into a coffee filter like contraption. Gravity and winter do your work for free.
Your statement above is probably true (do a search for “ethanol” here on SDMB in teh last month for some more good threads on that topic with cites to recent research).
But the “more energy to make” agrument is based on the total lifecycle, from the diesel used to drive the tractor to plow the field before planting the corn all theway through to the diesel used to drag the finished ethanol to the gas station. By “make” they don’t mean just the distillation process.
So even if you invent a process that made the distillation very efficient or even net energy-positive, you might still only be improving 5 or 10% of the total process efficiency.
Another problem: how free of water can you get the stuff at natural temperatures? 80 proof applejack may be possible, but that’s still about 60% water. You’d have to get it as near the alcohol freezing point as possible. (A very cursory google shows me a figure of -117C). That would be very energy intensive.