Browsing by Author "Huhtinen, Werneri"

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  • Design of a multi-fuel heat exchanger reactor - A unit for a proof-of-concept system for decarbonizing deep-sea shipping with hydrogen carriers and solid oxide fuel cells
    (2024-06-10) Kumpunen, Luukas
     Sähkötekniikan korkeakoulu | Master's thesis
    The global maritime shipping industry, responsible for approximately 2.8% of global greenhouse gas emissions, is seeking to reduce its carbon footprint in alignment with the EU Green Deal's net-zero emissions (NZE) target by 2050. Fuel cells, particularly solid oxide fuel cells (SOFCs), offer a promising solution for powering ships using hydrogen carriers as alternative fuels. The FuelSOME project aims to decarbonize the maritime sector by evaluating the feasibility, flexibility, and scalability of SOFC technology for high-efficiency power conversion using ammonia, methanol, and hydrogen. This thesis focuses on designing a heat exchanger (HEx) reactor to decompose ammonia and methanol, powering an SOFC for extended periods. The motivation for using a HEx reactor comes from its ability to increase the system efficiency by using residual heat from other components. The reactor design is driven by efficiency considerations, ensuring it can withstand the defined operation conditions and achieve effective decomposition rates. Using simulations and design tools from literature, the HEx reactor was designed in collaboration with AVL List GmbH. Experimental testing of catalyst-coated plates confirmed the feasibility of ammonia decomposition at 650 C. Although the assembly of the designed reactor was not completed within the thesis timeframe, the design process successfully combined analytical and simulation modeling, supported by literature review and experimental data. The finalized design, meeting the initial criteria at theoretical and simulation levels, sets the foundation for subsequent testing and optimization. This study, conducted on a lab-scale system, emphasizes the need for additional research to address variables encountered in scaling up to real-world applications, aiming for a reliable and efficient system for maritime use.
  • Development and characterization of an aqueous phase methanol reformer for a fuel cell system
    (2021-05-18) Huhtinen, Werneri
     Kemian tekniikan korkeakoulu | Master's thesis
    This master's thesis investigates the performance of a methanol fuelled aqueous phase reformer (APR) as a hydrogen production method for a 5 kW combined heat and power system, which is based on high temperature proton-exchange membrane fuel cell technology (HT-PEMFC). The literature review introduces the high temperature proton-exchange membrane fuel cell technology and the principles of the aqueous phase reforming. The focus is on review of the operation conditions, the reforming phenomena, and the catalyst materials. The experimental part represents the structure of the test bench system, describes the performed experiments, and evaluates the results. The test bench setup was targeted to reach 10 % of the hydrogen production capacity of the full scale system. The performance of two chosen catalysts, Ni/CeO2-ZrO2 and Pt/Al2O3, are investigated in the conditions of 160-190 C and 10-40 bar. The temperature conditions base on the temperature of the waste heat produced in the fuel cell system. The experiments with Ni/CeO2-ZrO2 catalyst failed due to the low activity and deactivation of the catalyst. With the Pt/Al2O3 catalyst, the highest achieved hydrogen production rate was 2.05 mmol/min and it was reported at conditions of 189.2 C and 26.1 bar(g). This was only 0.23 % of the hydrogen demand of the full scale system. When temperature conditions were in range of 160-180 C, the reached production rates were significantly lower. Overall, the achieved hydrogen production rates were too low to meet the requirements of the final application. It appeared that activities of the tested catalysts were not high enough in the test conditions. In future, either research of novel catalysts or experiments in higher temperatures are required, to improve the performance of the APR system. However, if temperature conditions are elevated, the APR could not be heated with the waste heat of the HT-PEMFC system.
  • Ohutkalvohaihdutus biopohjaisten prosessien yksikköoperaationa
    (2018-08-28) Huhtinen, Werneri
     Kemiantekniikan korkeakoulu | Bachelor's thesis