Woody biomass originates from trees including stems, branches, barks as well as forestry slash 鈥撎齮he technology and materials developed in this project could help solve the problem of slash wood washed away from forests in heavy rain. Together with wastes from manufacturing traditional wood products, it can be used as solid fuel for energy or converted to liquid fuels, gaseous fuels and chemicals through various technologies.
PhD student Chichi Zhang is developing technology and metal oxide materials to help produce green hydrogen from New Zealand鈥檚 abundant supply of woody biomass. She is pictured next to a fluidised-bed reactor for chemical looping biomass steam gasification. (Photo credit: University of mini传媒)
Sustainable Development Goal (SDG) 7 - Affordable and Clean Energy
A PhD student in Chemical and Process Engineering, Zhang鈥檚 research centres on how to convert the woody biomass into a hydrogen-rich gas product with increased hydrogen yield. The thermochemical process adopted in her research is known as chemical-looping biomass steam gasification.
鈥淲e鈥檝e been using temperatures of up to 1000掳C in the process, and by adding metal oxides, we can enhance the hydrogen yield by over 50 per cent. These metal oxides can be used numerous times in the chemical-looping biomass process,鈥 Zhang says.
The hydrogen-rich gas produced from the research will be further processed to convert other gases, such as carbon monoxide and methane, to hydrogen and carbon dioxide.
While the concept of this technology has been proposed in previous studies, Zhang has developed a new metal oxide that has a longer active life.
鈥淢etal oxides are the key for developing this technology but the common issue is that their lifetime is often short, which limits the practical application if they can鈥檛 be used again,鈥 she says.
Her project is the first part of an integrated process to produce green hydrogen from woody biomass. Eventually, the hydrogen and carbon dioxide mixture will be separated to produce pure hydrogen and pure carbon dioxide. The latter parts of the process are being investigated by other members of UC鈥檚 research team, led by Professor Shusheng Pang, Zhang鈥檚 PhD senior supervisor.
Zhang says high purity hydrogen is a clean energy carrier, but it doesn鈥檛 exist naturally on earth. 鈥淪o, it鈥檚 important to produce green hydrogen to help curb carbon emissions. To date, the main technology to produce hydrogen is methane steam reforming but methane is not renewable.鈥
Zhang鈥檚 research is part of a听larger research programme听evaluating the overall technical, economic, and environmental performance of hydrogen production and its commercial viability.
Read more stories听about how University of mini传媒 researchers are contributing to Aotearoa New Zealand reaching its energy goals by 2050.
.jpg)
