Veridium Converting Exhaust Carbon Dioxide from Ethanol Production into Biomass for Ethanol and Biodiesel

23 February 2006

Veridium Corporation is applying its algae-based carbon-dioxide scrubber to convert exhaust carbon dioxide from the fermentation stage of ethanol production facilities into biomass for subsequent use in ethanol or biodiesel production.

Veridium, via its majority owner Greenshift, has a cynaobacteria (blue-green algae)-based bioreactor process for reducing greenhouse gases emissions from fossil-fueled combustion processes. (Earlier post.) The algae (a recently discovered iron-loving cyanobacterium, tentatively named Chroogloeocystis siderophila, discovered thriving in a hot stream at Yellowstone) grow in the bioreactor on membranes of woven fibers.

Capillary action wicks water to the algae, fiber optic cables channel sunlight into the glow plates, and ducts bring in the exhaust gas. In concept, this is very similar to GreenFuel Technologies’s “Emissions-to-Biofuels” reactor; the implementation is, however, quite different.

The new technology is simple and scalable, and was originally designed to stimulate additional revenues for power plant operators while decreasing plant emissions.

The algae use the available carbon dioxide and water to grow new algae, giving off pure oxygen and water vapor in the process. Once the algae grow to maturity, they fall to the bottom of the bioreactor where the algae can be harvested for other uses several times per day. One such use is conversion into clean fuels such as ethanol and biodiesel.

Ethanol is made from starch-based feedstocks and biodiesel is made from animal fats and vegetable oils. Corn, the primary feedstock for ethanol production today, contains about 66% starch and 3-4% oil.

Veridium’s new BioStarch Recirculation System routes exhaust carbon dioxide from the fermentation stage of the ethanol production process through Veridium’s bioreactor where it is consumed by algae that are about 94% starch and about 6% oil.

The algae convert exhaust carbon dioxide and sunlight into biomass. This biomass is a very efficient feedstock for ethanol production and is itself a concentrated source of the primary ingredient of ethanol. It doubles in mass several times per day—a rate much faster than plants, and it does all of this on a footprint that is orders of magnitude less than the surface area required for crops.

That said, this technology is by no means a replacement for crops. Traditional ethanol feedstocks are still required to generate the quantities of carbon dioxide needed to make our bioreactor effective.

—David Winsness, CEO of Veridium’s industrial design division

Veridium also recently announced the receipt of its first order for its system that extracts high-grade corn oil from a corn ethanol by-product called distillers dried grain (DDG). The corn oil can then be used as a feedstock for biodiesel production. (Earlier post.)