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Scientists at the Department of Energy’s Pacific Northwest National Laboratory (PNNL) have developed an innovative continuous chemical process that produces useful crude oil within minutes from harvested algae. The development has been reported recently in the journal Algal Research. The technology has been licensed by Genifuel Corp., a biofuels company based in Utah. The company is working with an industrial partner to build a pilot plant employing this technology.

In this unique chemical process, wet algae are pumped into a chemical reactor, which produces crude oil from it in under an hour. The byproduct material produced in the process contains phosphorus, which can be recycled to grow more algae. This crude algae oil can be converted into gasoline, diesel fuel, or aviation fuel with additional conventional refining.

Cost has long remained a key roadblock for algae-based fuels. However, with PNNL’s technology, it is now possible to harness algae’s energy potential efficiently. The technique also incorporates a variety of methods to bring down the cost of algae fuel production. The production process has been simplified by the scientists at PNNL by combining multiple chemical steps into a single continuous process.

The most important cost-saving step is that the process works with wet algae, unlike various other processes that require the algae to be dried. Dried algae process consumes a lot of energy and is expensive. The new wet algae process is a major breakthrough because of its lower cost. It also offers added benefits such as the potential to extract usable gas from the water and then recycle the remaining water and nutrients to promote further growth of algae. This effectively brings down the overall cost further.

The PNNL technique eliminates the need for complex processing solvents such as hexane to extract the energy-rich oils from the rest of the algae. This technique makes use of the whole algae, subjecting it to very hot water under high pressure to tear apart the material, and converting most of its biomass into usable liquid and gas fuels.