WSU scientists convert algal biofuel waste into useful products
Researchers at Washington State University have developed a way to turn waste products from the process of converting algae into biofuel into a usable commodity. Hydrothermal liquefaction, in which algae is exposed to high temperatures and pressure to produce bio oil, creates a significant amount of waste, resulting in roughly 25-40% of carbon, and 80% of nutrients from the algae  being left to wastewater streams. The researchers discovered that using anaerobic microbes, the waste could be broken down and would become a bionatural gas without the use of harsh chemicals. The remaining solid substance can be used as a fertilizer.
In Washington, researchers at Washington State University and Pacific Northwest National Laboratory discovered a method of converting algae biofuel waste product into a usable and valuable commodity. Waste is produced during the first step of converting algae to biofuels via hydrothermal liquefaction. The wastewater is usually hard to process because it has so many different chemicals in tiny amounts, but researchers found that anaerobic microbes can break down the residue and converts it into a degradable bionatural gas. The remaining solid material can be used as a fertilizer.

“After removing the solids, about 10 percent of the output is bio oil, with the remaining 90 percent being a waste byproduct,” Andrew Schmidt of PNNL’s chemical and biological processes development group said in the WSU press release. “The fact that we’ve developed an alternative method to recycle or treat the leftover material means it’s more economical to produce the bio oil, making the potential for commercial use of the process more likely.”