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[GreenYes] Re: Compost-to-Switchgrass-to-Fuel?

I would hope that the biofuels industry would pay more attention to what the soil scientists are reporting -- that biofuels change the carbon that should be recycled back to the land and instead put it into fuel tanks.
At one of the conferences on biofuels that I attended, several soil scientists gave presentations on how the carbon level in soils is declining and that biofuels could make this situation much worse.
John Reindl, Recycling Manager
Dane County, WI
-----Original Message-----
From: GreenYes@no.address [mailto:GreenYes@no.address]On Behalf Of Kendall Christiansen
Sent: Monday, February 04, 2008 8:02 AM
To: GreenYes@no.address
Subject: [GreenYes] Compost-to-Switchgrass-to-Fuel?

Re the recent post about the prospect of using compost to create biofuels, an EPA award-winning example in Seattle was reported last April, in relevant part (see comment that follows):

King County Executive Ron Sims announced that the county will bring about 2 million gallons of homegrown biodiesel to King County to power Metro buses.

"This is another case of the county turning waste into a resource," Sims said in a statement. "This time biosolids from our local wastewater treatment process are being used to grow canola that will be refined into biodiesel to power our local transit system. This ultimate act of recycling shows how far we've come in developing new approaches to creating energy independence while reducing our carbon footprint."

The biosolids are retrieved from two King County wastewater treatment plants and transported to Sunnyside to fertilize canola.

"Biosolids (are) very high in nutrients. I know that in Eastern Washington the biosolids are used to improve soils and fertilize a lot of different crops," said Annie Kolb-Nelson, the Media Relations Planner for King County Wastewater Treatment Division. It's "fecal matter, basically."

The canola crop is a test of a hypothesis by University of Washington scientists in 2003. King County teamed up with Natural Selection Farms of Sunnyside. Soon some of the annual 115,000 tons of biosolids were put to use by other area farmers as well.

Canola is crushed into oil by a seed-crushing facility in Sunnyside, then shipped to Seattle's Imperium Renewables for processing into biodiesel. The biofuel will be enough to run all Metro diesel-powered buses on a 20 percent mix of biodiesel and ultra-low sulfur diesel for nearly a year.

The “fecal matter” comment is not exactly accurate:  in fact, biosolids across the U.S. contains a significant portion of food waste that begins its route via a food waste disposer (aka garbage disposal; common in most U.S. homes), traveling through underground sewers (no trucks) to wastewater treatment plants for processing into compost-quality biosolids, often via AD and with energy capture.  After all, food waste is similar to human waste:  @ 70% water, with a slightly higher ratio of C:N than human waste, which is helpful in most wastewater treatment processes, and enriches the quality of biosolids.  All in all, an important aspect of recycling that shouldn’t be overlooked by those focused on managing solid waste.

For an interesting essay on the historical and contemporary recycling of human waste, read “Wasteland” in the current issue of Harper’s.

Kendall Christiansen


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