Food and Feces Could be the Fuel of Tomorrow

Posted by Sonja Begemann on Tue, 02/05/2019 - 11:19

In its quest to find greater efficiencies and reduce reliance on fossil fuels, the University of Illinois found a way to convert wet food waste and animal waste into diesel fuel. The fuel will be mixed with traditional diesel and has the same combustion efficiency and emissions profile.

“The demonstration that fuels produced from wet waste can be used in engines is a huge step forward for the development of sustainable liquid fuels,” said Brajendra K. Sharma, research scientist at Illinois Sustainable Technology Center at the University of Illinois’ Prairie Research Institute and co-author of the study in a recent news release.

One of the biggest challenges researchers found in converting wet waste to fuel is drying—it takes nearly as much energy to dry it as they extract from it. The opportunity is rich, however, with 79 million dry tons of wet bio-waste from food processing and animal production available each year.

The solution? Hydrothermal liquification because it uses water to concert nonlipid (nonfatty) bio-waste components into biocrude oil that can be further processed into fuels, according to researchers.

While this isn’t the world’s first venture into waste converted into fuel, this could be the most efficient discovery yet. Researchers improved old methods to distill biocrude into useable fuels using esterification to convert higher percentages of distilled biocrude into blendable liquid fuel. This new fuel meets standards and specifications of standard diesel.

“We also were able to separate the distillable fractions from the biocrude oil,” said Wan-Ting (Grace) Chen, first author of the paper and professor at University of Massachusetts. “Using 10% to 20% upgraded distillates blended with diesel, we saw a 96% to 100% power output and similar pollutant emissions to regular diesel.”

The team is building a pilot-scale reactor to mount on a mobile trailer. When completed it has the capacity to proves one ton of bio-waste and produce 30 gallons of biocrude oil per day, according to Yuanhui Zang, University of Illinois agricultural and biological engineering professor who lead the study.