With about 210,000 gallons of oil spilling into the Gulf of Mexico each day, the recent explosion of a British Petroleum oil rig off the coast of Louisiana has stymied discussion of offshore drilling and has reinvigorated interest in alternative fuel sources.
Amidst mounting pressure to develop affordable biofuels and reduce dependence on foreign oil, University researchers have recently developed a hydrothermal process that extracts crude oil from microalgae rather than the ground.
Phillip Savage, professor of chemical engineering and lead investigator for the project, said he and his team of researchers sought to create a viable fuel product for widespread use.
“The idea was to make a liquid fuel compatible with the existing infrastructure that is in place for transportation of fuel, the distribution network and also use within existing engine technology,” he said.
According to Savage, the oil extraction process relies on a combination of hydrothermal, chemical and biological processing that takes advantage of microalgae — simple microscopic plants that lack leaves and roots — in its natural wet state.
“My laboratory, over the years, has done a lot of work on chemistry in water at high temperatures and pressures,” he said. “So it occurred to us that the research we’ve been doing and the expertise we have on hydrothermal chemistry could be applied here, because the algae grow in water.”
Savage continued, stating that pressure-cooking algae mimics the natural formation of petroleum from the decay of ancient marine organisms, which are subjected to extensive heat and pressure over millions of years.
Like the crude oil product that is pumped from the ground, the algae extract has unwanted components of oxygen, nitrogen and sulfur that decrease the fuel’s potential energy output, Savage said.
“There’s going to have to be additional work on converting what we get from liquefying the algae into something that would be more like a hydrocarbon fuel,” he said.
Savage added that the process for oil extraction and refining is not necessarily limited to microalgae but rather can be applied to any form of wet biological material, widening the range of available sources for the fuel.
“The general principle that the application of heat, pressure and water molecules can attack the macromolecular structure of lots of different types of biomass should apply in a general sense to things not limited to just algae,” he said.
Because the project received federal grant funding just last September, Savage said the oil extraction process is still in its infancy. He added that separation and catalytic treatments are still pending in order to differentiate the algae oil product for all uses and remove contaminants, respectively.
As current global use of fossil fuels depletes natural oil reserves, Savage said he remains hopeful that hydrothermal processing of biomass could be a real future contender as a feasible source of fuel.
“If the research is successful technically, then the next part will be to see if it passes the economic hurdle and the environmental hurdle,” he said. “There’s nothing right now that I can point to and say, ‘here’s an obstacle that would prevent this (process) from ever being a major player in meeting our energy needs.’ ”