[Gasification] Path from Biomass to Ethanol by way of Ethane.

[Mark Ludlow]

Dan,

Converting a crystalline, linear polysaccharide such as cellulose into food
that the yeast Saccharomyces cerevisiae can convert to ethanol and CO2 is
tough. Even Ma Nature has not figured out this problem, at least in the more
successful way that she has employed photosynthesis to split oxygen from
hydrogen in water. All bio-schemes I am aware of require virtually as much
energy to reduce cellulose biomass to particles small enough to provide
sufficient surface area for the de-polymerizing enzymes to work, as is
recoverable in output energy. We all know that fungi are quite efficient at
breaking down woody biomass (and wooden boats, fence posts, etc.), but not
in a manner that lends itself to practical energy production. Even corn
conversion to ethanol requires an amylase to reduce the branched-chain, corn
starch into a simple sugar usable by Saccharomyces cerevisiae.

Anaerobic digestion favoring methanogenic bacteria requires a fairly
specific environment and still needs lots of comminution of feedstock (read:
chewing of cud), unless we hire some herbivores to do it for us and harvest
their reduced-quality end-product (manure).

I think gasification is the logical reduction method for every feedstock
that cannot be efficiently bio-converted or bio-digested. In a perfect
world, the sludge from methane-producing digesters would be used as a soil
amendment to assist in the growing more corn or other relatively-easily
convertible feedstock. Bio-sludge (there may be an image problem with this
name!) is everything remaining after fermentation or digestion with the
intention of recovering inflammable liquids or gases. All other woody
materials would be targeted toward gasification, until that point in our
scientific evolution that efficient enzyme-mediated bioconversion would
become net-energy competitive (don't hold your breath).

With respect to gasification, much discussion on this List is dear to my
heart: how to "get off the grid" and reduce exposure during the inevitable
crunch coming when the manure hits the ventilator and cheap, energy-dense
oil is priced by the gram, not barrel. However, civilization on Earth will
little benefit from a further segregation of humanity into those with
"five-acres and independence", and those unlucky enough to live without any
means of becoming energy self-sustaining.

The problems we face as a civilization, we created as a civilization. Coal
ushered in the Industrial Age. And coal may be the bridge to a more
enlightened energy economy that combines biological processes (mimicking
nature) as well as advanced industrial processes such as biomass
gasification, that provide feedstocks which produce building blocks for
industrially useful chemicals which are now petrol-derived (out of sheer
convenience). When the chemical process industry is forced to re-focus on
something besides cracked petroleum products or natural gas-e.g. a
normalized version of woody biomass distillation-it will respond with new
processes and commodity intermediates.

Those who wish to capture fly ash, remove tars, reduce CO2 to CO and
generally improve the quality of gasification products are all part of the
total solution. So are the horticulturists who lead us to planting those
particular species of plants that are optimized in their primary function of
converting solar radiance, CO2 and H2O (with some nitrogen and other
nutrients that our bio-digesters supply) to carboniferous biomass.

Gasification is the single, most-tolerant method of converting biomass to
useful forms (except for a crackling campfire).

Mark Ludlow




-----Original Message-----
From: gasification-bounces at listserv.repp.org
[mailto:gasification-bounces at listserv.repp.org] On Behalf Of
Carefreeland at aol.com
Sent: Friday, August 04, 2006 9:46 PM
To: bioconversion at listserv.repp.org; gasification at listserv.repp.org
Subject: [Gasification] Path from Biomass to Ethanol by way of Ethane.


Friends, 
       Is there a simple, economic path, to convert a significant amount of
biomass material to Ethanol, First converting to Ethane, then converting to
Ethanol?  Would Gasification by Pyrolisis or Taylor made Anaerobic
Fermentation work best? I can use all of the by- product Methane.
        Ethanol seems to be where it's all going these days. Would cellulose
laden biomass be better in the gasification process, and nitrogen laden
biomass be better in the fermentation? Could nitrogen be extracted from the
process as fertilizer? 
        I wanna build a refinery to fuel my small business.  Has anybody
seen the price of fertilizer lately? 
       
       Dan Dimiduk
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