Biomass Refinery Operation: Upstream and Downstream Processing at High Pressure
William Jacoby, an associate professor of biological engineering with a joint appointment in chemical engineering at the University of Missouri and Mizzou Advantage seed grant recipient, has a simple, one-word answer to questions concerning renewable, clean and affordable energy alternatives: biomass.
Jacoby and his research team are exploring the process of turning biomass into vapor fuels using super critical water gasification (SCWG), with promising results.
“This process has been around awhile, but it hasn’t been investigated thoroughly,” said Jacoby. “Several years ago, I began to study supercritical water gasification because I thought the process had great potential, and I still do. We gasify biomass at a higher rate and with higher efficiency than previously reported in the literature.”
To begin the process, water is preheated within the continuous reactor apparatus. The biomass is streamed in and passes through the reactor’s furnace for only a few seconds, where the supercritical water serves as both a solvent and a reactant as a small proportion of the water splits to contribute hydrogen and oxygen to the reaction.
Biomass decomposes in this high-temperature, high-pressure process. There is very little oxygen, so it doesn’t burn. Instead it gasifies, forming hydrogen, methane and carbon dioxide. This vapor mixture is similar to natural gas produced at high pressure.
A Mizzou Advantage seed great is making further research into super critical gasification of biomass possible.
The group is using algae in their current experiments, but Jacoby says any type of biomass could be utilized, from agricultural waste to sewage sludge. He envisions SCWG as an “end-of-pipe” technology at the biomass refinery. “After valuable products are extracted, the wet sludge that’s left over can be converted to fuel gas via SCWG,” he said.
Jacoby is also able to foster interest and expertise about biomass conversion technology to undergraduates and graduates in the Carbon Recycling Center research lab, where students work on various projects, such as a recent effort to use supercritical carbon dioxide to remove oil from soybeans.
“The impact of our research product may be significant, and I hope it is,” said Jacoby. “However, I know that the impact of training students to embrace and implement the biomass refinery concept will be positive and long-lasting.”