Algae growing in mixed media with produced water. Photo courtesy of Paul Laur (Eldorado Biofuels) |
Scientists
recently conducted the first pilot-scale test of algae growth using
water from an oil-production well in Jal, New Mexico. This impure water,
called “produced water,” is pumped to the surface concurrently with the
extraction of oil, gas, and coal bed methane from underground
formations.
Water
is the largest quantity resource other than land that will be required
for algal biofuel production. LANL’s biofuels research aims to show that
algae cultivation need not impinge upon limited fresh-water resources,
particularly in arid regions. Alternate resources, such as produced
water, which has more salinity than fresh water, can be used.
Oil
and gas production in the United States currently brings about 800
billion gallons of produced water to the surface annually along with the
oil and gas. Although the water has characteristics suitable for growth
of marine algae, up to 98% of this water is routinely disposed
as a waste product. These large quantities of saline water have great
potential value for algal biofuel production.
Testing growth of algae
In
collaboration with the Texas Agrilife Research facility in Pecos,
Texas, the researchers grew a salt-tolerant, oil-producing algae in
approximately 80-gallon reservoirs. The researchers compared the algae
growth in the Pecos city water with that in produced water. Initial
growth of algae with low concentrations of produced water was similar to
that in city water. However, higher produced-water concentrations of
dissolved solids became growth limiting. Testing is set to continue,
with scientists adjusting their treatment methods.
Researchers
include the Laboratory’s Jeri Sullivan, Cindy Dean, Tom Yoshida, and
Blossom Cordova of Chemical Diagnostics and Engineering (C-CDE); Mike
Rearick of Earth Systems Observations (EES-14); and Greg Wagner of
Physical Chemistry and Applied Spectroscopy (C-PCS), along with
collaborators at Eldorado Biofuels (Paul Laur, president), Alfonse
Viszolay of V.M. Technologies, and the National Alliance for Advanced
Biofuels and Bioproducts (NAABB) consortium.
About NAABB consortium
The
overall goal of the NAABB consortium is to produce new technologies
that can be implemented in developing the algal biofuel industry. DOE
Energy Efficiency and Renewable Energy funds NAABB through the American
Recovery and Reinvestment Act stimulus funding. The work supports the
Laboratory’s Energy Security mission area and the Materials for the
Future capability.