A group of engineers from PNNL turn algae into usable biofuel in minutes, a process that takes millions of years in nature.
A group of engineers at the Pacific Northwest National Laboratory (PNNL) has created a new biofuel that uses algae that produce crude in a matter of minutes. The results of this study were published recently in the journal Algal Research, and the biofuel company Genifuel Corp. has patented the technology and is working with an industrial partner to build a pilot plant that will start producing crude.
The scientists and engineers at the PNNL simplify the production of crude oil by algae by combining several chemical steps into a single continuous process, which consists of pumping a slurry of wet algae through a chemical reactor, which in less than an hour is converted into:
- crude oil, which can be converted into aviation fuel, gasoline or diesel fuel.
- clean water, which can be recycled to grow more algae.
- burnable gas, which can be burned to generate electricity or cleaned to create vehicle fuel in the form of compressed natural gas.
- nutrients such as nitrogen, phosphorus and potassium, which are essential for algae growth.
This processing method cuts production costs significantly because it works using algae slurry, eliminating drying, which is an expensive process that uses a lot of energy. It also eliminates the need for a complex process with solvents such as hexane to extract the energy-rich oils from the algae. Instead, the PNNL team works with whole algae, subjecting it to very hot water (350°C) under high pressure (3,000 PSI) to tear apart the substance, converting most of the biomass into liquid and gas fuels. These processes are known as hydrothermal liquefaction and catalytic hydrothermal gasification.
Genifuel Corp. has worked closely with the PNNL team since 2008, licensing the technology and working initially with PNNL through DOE’s Technology Assistance Programme to assess the technology.
“This has really been a fruitful collaboration for both Genifuel and PNNL”, said James Oyler, president of Genifuel. “The hydrothermal liquefaction process that PNNL developed for biomass makes the conversion of algae to biofuel much more economical. Genifuel has been a partner to improve the technology and make it feasible for use in a commercial system.”