Ethanol-corn vs sawgrass

[IndyIan]

My main worry about bio fuels is that the micro nutrient cycle is being ignored. Copper, Iron, Selenium, etc are elements that are necessary for healthy plants and animals.
Eventually someone will figure out a way to convert cellulose to some sort of fuel and then any plant is fair game. If you mow things down for long enough and cart it all away eventually nothing will grow and we'll have bigger problems than figuring out how to drive around.

Corn is terrible for this and chemical fertillizers can mask the problem for a while but eventually the soil will be depleted.

Maybe the production of alcohol is so pure that it contains only carbon, hydrogen, and oxygen? Then the rest of the elements are salvagable and can be used for fertilizer again? I don't hear much about this but every farmer knows a field or two where someone grew corn for too many years and basically made it useless even with the standard fertillizers
Ian.

[Unforgiven]

Very true point on how a field can be burned out on a crop. I remember my paternal grandfather giving me that little instruction long ago which explained to me why he rotated fields to lay "fallow" as the term is used. Almost tempted to look into his old farm and see if the merits of raising sawgrass would be worth the effort...

[jim-frank]

Originally Posted by Unforgiven

Very true point on how a field can be burned out on a crop.

Modern farmers are quite aware of the need to rotate crops to avoid depletion of various nutrients.

I wonder how a cycle of [corn/sugar beets/something else] would work. Sugar beets are a good source of directly fermentable sugars, and the waste can be fed to animals or composted back into fertilizer.

There are lots of paths to any given end. It's mainly a matter of getting the government regulators cut out of the loop, and letting the farmers and ethanol producers decide for themselves what is the most economical and profitable route to take.

[rmay635703]

Originally Posted by jim-frank

Modern farmers are quite aware of the need to rotate crops to avoid depletion of various nutrients.

There are lots of paths to any given end. It's mainly a matter of getting the government regulators cut out of the loop, and letting the farmers and ethanol producers decide for themselves what is the most economical and profitable route to take.

Sadly most farmers aren't that modern. My relatives have been growing soy and corn only for over 25 years (my great uncle for 60yrs), no rotation to anything else. Current "hybrids" are designed to grow on water and nitrogen like a hydroponic. Our government stated that soil was devoid of mineral content in the 40's and warned of huge health effects from heart disease to anurism. Sadly they quit caring shortly after.

What is really needed in many parts of our country is a broad spectrum mineral based "Fertilizer" of some sort, best source would be ocean water if you could take out the sodium salt, though some studies say our soil needs some salt and in many areas there isn't even enough sodium content in the soil for it to be healthy. It would take many years though to start undoing the damage we have already done in our attempts to sterilize the soil.

We should also stop the practise of growing corn, the type of corn we grow is nutritionally devoid and not fit for human consumption without processing. Going to a traditional crop rotation with a variety of food crops would help break our dependance on foreign vegetables and fruits since we no longer grow much in the way of vegetables in mass.

We should also move from Beef to goats, sheep, deer, chickens, turkeys, pigs, etc. As they are all more efficient at converting food into meat and in some cases milk. Not that beef is bad just that it should not be our only real meat choice.

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. No one seems much interested though in making a REAL green ethanol solution however as it means slower production or a larger footprint. Also waste foods should be used for ethanol or methane production, not viable food stores.

This all seems like common sense but when a lobby is involved nothing ever makes sense.

[jim-frank]

Originally Posted by rmay635703

Sadly most farmers aren't that modern.

/snip/

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?

[jamesqf]

Originally Posted by jim-frank

Maybe Colorado farmers are at the cutting edge, then.

Crop rotation is hardly cutting edge, considering that it was used in the Middle Ages: Farming in the Middle Ages

Or instead of a monoculture of any plant, consider mixed prairie. The plants are mostly perennials, so you just mow it now & then.

It's the heat to distill that really takes up energy.

So use the waste heat from your local power plant.

[jim-frank]

Crop rotation is hardly cutting edge, considering that it was used in the Middle Ages:

I was trying to be gentle.

The waste heat from power plants is only relevant if you have a large steam driven power station in your ethanol plant's back yard.

Around here, the nearest large (coal fired) power plant is about 300 miles away. Everything local is hydroelectric except for some standby and emergency plants.