By KEVIN MCCULLEN
RICHLAND, Wash. — Scientists in Eastern Washington are at the forefront of research into an ancient practice that shows promise as a clean fuel source, a way to improve soil condition and to capture carbon that otherwise would be released into the atmosphere.
Researchers from Pacific Northwest National Laboratory, the federal Department of Agriculture’s research station in Prosser and Washington State University have been integral figures in studies of biochar and its potential uses.
Biochar, a charcoal-like material, is produced when biomass – including wood, plant and animal waste – is burned in the absence of or under low oxygen conditions so the material doesn’t combust.
This process, called pyrolysis, thermally decomposes the waste into biochar, bio-oil and syngas. Biochar and bio-oil show commercial promise and syngas offers a power source that can run a pyrolyzer.
The USDA’s Agricultural Research Service has estimated that if the United States were to pyrolyze 1.3 billion tons of various forms of biomass annually, it could replace 1.9 billion barrels of imported oil with bio-oil. That would represent about 25 percent of the annual oil consumption in this country. In addition, USDA estimates the country could sequester 153 million tons of carbon annually by adding biochar to soils.
Mobile ‘biochar’ machine to work the fields
An ancient technique to fertilize soil by creating charcoal from plant waste is being revived to tackle some of today’s environmental problems.
The latest company to pursue manmade charcoal, called biochar, is Biochar Systems, which has developed a biochar-making machine that can be pulled by a pickup truck. Two customers–a North Carolina farm and the U.S. Bureau of Land Management–will be begin testing the units this fall.
The unit, called the Biochar 1000, is designed to convert woody biomass, such as agricultural or forestry waste, into biochar, a black, porous, and fine-grained charcoal that can be used as a fertilizer. It uses pyrolysis–slowly burning biomass in a low-oxygen chamber–to treat 1,000 pounds of biomass per hour, yielding 250 pounds of biochar.
There still isn’t a well established market for selling biochar, but there’s growing interest among researchers in the process as a way to cut greenhouse gas concentrations. The United Nations has proposed classifying biochar as a carbon credit for sequestering carbon from the atmosphere.