Tiina Keipi works as a product engineer in Valmet’s Recovery business unit. Before she joined Valmet she did her doctoral dissertation at the Tampere University of Technology but not in the area of recovery boilers but about Technology Development and Techno-Economic Analysis of Hydrogen Production by Thermal Decomposition of Methane.
Tiina Keipi’s dissertation wasn’t just an any dissertation, but one that was recognized by the City of Tampere Science Fund in September 2019, and in November awarded the best doctoral dissertation by TEK, the Academic Engineers and Architects in Finland.
“The transition to the hydrogen economy has been proposed as a sustainable solution for the simultaneous depletion of fossil fuels and the increase in global energy demand since the 1970s. However, the current fossil fuel-based hydrogen production causes significant CO2 emissions. On the other hand, extensive hydrogen production by water electrolysis powered by renewable electricity requires a remarkable increase in the renewable electricity generation capacity. Therefore, alternative solutions are needed in order to promote the hydrogen economy, develop hydrogen infrastructure, and smoothen the transition to the wide-scale renewable-based hydrogen production in the future,” Keipi explains as a starting point for her work.
In her dissertation, thermal decomposition of methane (TDM) was studied as a transition period solution towards the hydrogen economy. In TDM, methane is converted to hydrogen and solid carbon thereby avoiding the direct CO2 emissions.
“My dissertation focused on combating climate change. I studied an innovation that facilitates carbon-neutral utilization of natural gas. The produced solid carbon can be utilized to produce useful chemicals, which is in line with the principles of the circular economy,” Keipi explains.
“In my doctoral dissertation I used multiple methods: experimental research, modeling and also made economic viability calculations. It was very rewarding to be able to look at the method from all these angles. For the modeling part I worked together with Norwegian University of Science and Technology in Trondheim where I was a visiting researcher for five months.”
She was responsible for the design and, to a large extent, the construction of the test reactor which was build at the Tampere University of Technology.
“The studied TDM method can produce hydrogen with lower CO2 emissions. But to be economically viable, there needs to be a commercial application for the solid carbon produced as a final product,” Keipi sums up the main results of her dissertation.
In addition to providing a clear roadmap for anyone willing to take the TDM method to next stage – a demonstration scale plant, the four-year road to doctoral degree gave Keipi valuable experience for her future career in Valmet.
“Even though I’m not continuing this work, it is available for the scientific community, companies and investors. Based on the mathematical modeling and dimensioning of the equipment it is possible to design a demonstration plant. And the economic calculations give a backbone for the investment decision,” Keipi describes her legacy for the road toward hydrogen economy.
“For me personally this gave valuable experience about working in projects, process design and teaching. I learned how to cooperate between people from different backgrounds, universities and companies, and I got to experience that best results are achieved when looking at a challenge from various angles using multiple methods. This has not satisfied my willingness to learn; on the contrary, I only noticed I want to learn and challenge myself more,” Keipi concludes.
Currently Keipi is using her skills as a product engineer for Valmet’s recovery boilers working on the Chilean ARAUCO recovery boiler delivery project, covering the equipment dimensioning and process design all the way to the preparation for the eventual commissioning of the boiler.