A few weeks back, Jeremy posted about General Motors working with cellulosic ethanol start-up Coskata. See "GM Banks on Coskata's Cellulosic Ethanol Breakthrough".
"Coskata and GM expect to have a pilot plant up and operating by the fourth quarter of 2008; the ethanol will be used to test vehicles at GM's Milford Proving Grounds. The start-up expects to have a commercial-scale plant with the capacity to manufacture 50-100 m gallons of ethanol per year going by 2011."
Since word about GM's involvement with Coskata got out, we've been wondering what sort of super-model bacteria were being cultured to result in such a low water consuming, greenhouse gas reducing, and energy efficient means of Ceetoh production? What if a genetically modified (the other kind of GM) monster got out of Coskata's fermentation process and ate up our lovely trees? Not to worry. It seems the anaerobes growing in Coskata's tanks and growth media are as natural as mud - they were found in nature by a microbiologist.
""We're smart, but we're not smarter than everybody else," said Todd Kimmel, a Coskata co-founder, earlier this month. "We found organisms that are unique and rare in nature."
It all began when Ralph Tanner, a microbiology professor at the University of Oklahoma, discovered [the organism] in oxygen-free sediments in a swamp."
When someone uses the word 'swamp', which is an archaic way of indicating anything muddy and wet ranging from a natural wetland to a manure lagoon, it's usually an indication that they don't spend much time in nature. So, we have no clue as where the Tanner-found bacteria were actually sampled from.
Looking at the publication listing of Dr. Tanner (pictured fishin' below), it seems pretty clear the anaerobe in question is a Clostridium, possibly C. ljungdahlii or variant. BIOwaste Blog reports that as far back as 1991, a BRI Energy pilot plant located outside the City of Fayetteville, Arkansas was using a Clostridium bacteria in a manner similar to that outlined in Jeremy's Coskata post.
A clue as to what differentiates the Coskata process from BRI's was found in Technology Review:
"But Andy Aden, a senior researcher investigating cellulosic ethanol at the National Renewable Energy Laboratory in Golden, CO, says one problem with such approaches is that it's been difficult to make the syngas accessible to the bacteria, since syngas doesn't dissolve easily in water. Coskata has tackled this problem with a new bioreactor design in which bacteria grow in dense biofilms on the outside of hollow fibers. Syngas is pumped through the inside of these fibers and diffuses through them directly to the biofilm. Aden says the biofilm approach sounds promising, although he cautions that such systems have been difficult to scale up to the commercial scale."
So there you have it. GM buys into non-GM organism-based process which holds high promise for transportation fuel production mainly because of unique bio-reactor design. Anyone care to guess what those "hollow fibers" are made of? A bit of burrowing around in the patent literature might indicate where the hollow fibers idea came from. But we'll leave that for another day.
The moral of this story: don't be of afraid of the GM's; be kind to your friends in the swamp; and, remember that green tech innovation is seldom based on a single, sudden "breakthough," as our mainstream media would often have us believe.
Best of luck to your researchers, one and all. We need, and all living systems on earth need, all the innovation we can get. Even "swamp" critters.
Writing this post makes me want to go "swamp" fishin'.