ARS Bio-Oil Technology Heats Up
McGinnis April 6, 2007
Biofuels are a hot commodityand thermochemical processing
is making them even hotter. New research by Agricultural Research Service (ARS) scientists could soon lead to improved
techniques for producing bio-oils.
At the ARS Eastern Regional Research Center (ERRC)
in Wyndmoor, Pa., scientists are exploring different methods for making fuels
from biomass, which includes materials such as energy crops, corn stover and
The conversion method known as thermochemical processing involves
heating the biomass in a reactor to produce liquids (bio-oils) and synthetic
gases (gaseous fuels such as hydrogen and methane).
At the ERRC, chemical engineer
A. Boateng and mechanical engineer
Goldberg, working with Daren E. Daugaard of the
University of Texas-San Antonio, have
developed a bench-scale fluidized bed reactor to convert switchgrass and other
energy crops into bio-oil in a process called pyrolysis. This method uses
extreme heat to break down organic materials in an oxygen-free environment.
One advantage of the reactor is that it demonstrates the potential of
in-field conversion of biomass into oil. The resulting oil is more energy-dense
than the original biomass, so transporting oil from the field to a central
refinery is more economical than moving hay or biomass pellets.
The bench-scale reactor maximizes liquid yield collection by
incorporating an electrostatic precipitator (ESP), a filtering device that
removes fine liquid droplets from the gas flow. The bio-oil derived from the
ESP has several desirable properties, including relatively low water content,
resulting in higher energy density and superior transportability.
The oil collected by the ESP is suitable as a feedstock, because the
oil's energy density is higher than the average collected bio-oil. Further
refining can turn this oil into a more standard diesel fuel for use in
automobiles, farm equipment and other diesel-run machines.
about this and other ARS bioenergy research in the April 2007 issue of
Agricultural Research magazine.
ARS is the U.S. Department of
Agriculture's chief in-house scientific research agency.