April 10, 2008

In algae, a cleaner environment and renewable fuel

by Katherine Bielski


Many people may think of algae as no more than the gross substance that infests swimming pools.

But Dr. Qiang Hu, head researcher of Polytechnic campus's Department of Applied Biological Sciences, sees algae as an opportunity to solve many of the world's environmental problems.

Thanks to funding from the U.S. Department of Agriculture, the Defense Advanced Research Projects Agency, and the Science Foundation Arizona, Hu said he has been investigating the abilities of algae to produce fuel known as biodiesel while simultaneously neutralizing toxic carbon dioxide.

"Algae is not just a renewable fuel resource," Hu said. "Algae convert waste into a highly valuable product. On one hand they produce energy, and on the other, they clean the environment. It's a win-win."

Hu said although the field of alternative fuel sources has moved into the forefront of public perception, this has nothing to do with why he has been studying algae.

"I've spent my lifetime working on algae," Hu said, as he passed around a tray of algae cookies. "It has nothing to do with renewable fuel becoming the new craze. I completed my thesis on Algal Biomass Culture for Animal Feed and Human Mass Consumption in 1985."

His most recent project, a collaborative effort between the Polytechnic Department of Applied Biological Sciences and the Polytechnic Department of Mechanical and Manufacturing Engineering Technology, looks at the substance of algae once again.

Hu and Jerry Gintz, senior lecturer and project coordinator of the Mechanical and Manufacturing Engineering Technology department, led a team of undergraduate and graduate students in the creation of, what they call, "bioreactor vessels" used to grow algae.

"Dr. Hu is great researcher," Gintz said. "He had the grand vision, and we have the manufacturing and engineering know-how and also the facilities to build what he needed. This is a great example of two completely different areas working together."

The bioreactors are four feet tall by four feet wide, approximately nine inches thick and made of clear acrylic.

They are filled with water and a little bit of algae, placed in the sun, and a current of air and carbon dioxide, in a specific ratio, is run through the tank to promote algal growth and keep the temperature steady, Gintz explained.

When the algae have grown enough, they are removed, and the biofuel is extracted through a solvent-based extraction technique, after which it may be refined into diesel fuel, gasoline, or even jet fuel. This leaves behind what Hu terms "algal biomass," a highly concentrated factory of proteins, minerals and pigments, which is being investigated as a food source, pharmaceutical therapy and organic fertilizer, among other things.

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