Researchers eye farm waste as energy

ST. LOUIS, Missouri (AP) -- Washington University engineers using imaging technology have found that vigorous mixing helps microorganisms turn farm waste into alternative energy.

Hog and cow manure is a persistent pollutant from industrial-sized barns and feed lots, but can become a useful source of fuels like methane when broken down by bacteria.

A team of researchers including Washington University professor Muthanna Al-Dahhan used imaging technology to study how microorganisms break down manure. They found that vigorous mixing helps the process. The goal is to produce a simple method that farmers can use to treat their waste and generate energy.

"Each year livestock operations produce 1.8 billion tons of cattle manure," Al-Dahhan said in a statement. "Treating manure (with microorganisms) gets rid of the environmental threats and produces bioenergy at the same time. That has been our vision."

The research was funded by a $2.1 million grant from the U.S. Department of Energy given in 2001. Al-Dahhan said the new findings are just a small step toward making a reliable "digester" that farmers could use to turn manure into methane.

The technology has been getting more interest as energy prices rise, although large-scale investment has faltered recently along with projects to build new ethanol and biodiesel plants.

Last week in Clovis, New Mexico, Gibbs Energy President Joe Maceda said construction would be delayed on a $25 million plant that would make methane gas from cow manure. The project faltered after its primary investor was crippled financially because of the sub-prime mortgage crash.

Separately, in Mead, Nebraska, E3 BioFuels declared bankruptcy late last year and delayed plans to build a patented methane-from-manure system to power an ethanol plant. E-mail to a friend

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