University of Queensland students are investigating a process that uses waste biomass – crushed sugarcane stalks and leaf – to produce hydrogen for under $3 per kilogram.
Professor Damien Batstone said any carbon dioxide produced during the process is captured, making it carbon negative.
“150 students in 36 teams are analysing both thermal gasification, and the more cutting-edge ‘supercritical hydrothermal gasification’ method,” Batstone said.
“The new approach looks promising, with the cost as low as one third that of the current options.”
“The technology can be used with any waste biomass, including green waste and municipal waste streams, and the students’ economic models and design processes show it can be put into practise immediately.”
“Adopting this new hydrogen production approach could have a tremendous impact on the sugarcane industry as farmers seek alternative uses for their crops and mill infrastructure.”
“This offers an alternative pathway with potential for higher profits for canegrowers who may have considered exiting the industry, as well as job opportunities for regional areas and clear environmental benefits.”
“The process allows sugarcane to be used in ethanol and plastic production, while fully utilising the biomass residues.”
Batstone said agricultural residues were heated to between 400 and 1000 degrees Celsius to create “syngas”, then a series of conversion and separation processes generated pure hydrogen.
“It can be done at atmospheric pressure or at very high pressure in the presence of water,” he said.
“Gasification has been widely applied to coal processing but has not been applied to hydrogen production from biomass at large scale.”
The federal government’s 2019 National Hydrogen Strategy identified hydrogen as a critically important future source of energy.
“It flagged creating hydrogen using fossil fuels at $3 per kilogram with significant carbon emissions, and non-fossil-based renewable electricity at significantly higher prices between $6 and $11 per kilogram,” Batstone said.
“Industry professionals and UQ researchers are guiding the students in this emerging and vital field, and their work could have a real benefit for industry and the environment.”