Pretreating Nuisance Green Algae with Lye, Urea Increases Bacterial Production of Biogas

Algae/Other Aquatic Organisms/Seaweed, Feedstocks, Pretreatment, Process, R & D Focus, University/College Programs

July 1, 2021

Print This Article Share it With Friends

(American Institute of Physics/Phys.Org) For more than 60 years, algae have been studied as a potential feedstock for biofuel production, but the cellulose in their cell wall makes it hard to access the critical molecules inside and convert them to biogas.

In the Journal of Renewable and Sustainable Energy, an international research team reports their success in using urea and sodium hydroxide (NaOH, commonly known as lye or caustic soda) as a pretreatment of algae, which breaks down cellulose and more than doubles biogas production under their initial experimental conditions.

…

To produce biogas from algae, researchers commonly use a naturally occurring process called anerobic digestion, in which a type of bacteria break down the algae and produce a methane-rich gas mixture that can be purified. The resulting methane can be used in the production of heat, electricity, methanol, car fuel, and other clean energy sources.

This study presents the first steps toward optimizing conditions for such energy production, testing variations in time, temperature, and concentration of lye-urea pretreatment. Specifically, the most effective combination in this study was a 50-minute pretreatment at -16?C with a lye-urea concentration of 5.89%.

…

In the study, the feedstock was Enteromorpha, a macroalgae or seaweed responsible for green tide, an algal overgrowth that is damaging to tourism, aquaculture, and natural ecosystems. The global economic and ecological impacts of green tide have been increasing in scale and frequency since the 1960s.

Capturing this seasonal and emergent algae and converting it into a cost-effective and sustainable biofuel would have social and economic benefits beyond clean energy and bring us closer to a circular economy. READ MORE

“NaOH-Urea pretreatment for biogas enhancement from algal biomass anaerobic digestion,” Journal of Renewable and Sustainable Energy (2021). DOI: 10.1063/5.0048341

Comments are closed.

Advanced BioFuels USA