Katı oksit yakıt pilinin modellenmesi ve biyokütle gazlaştırma sistemi ile entegrasyonu

The growth of the world population and the development of industry based on technologies relying on fossil fuels increases the carbon dioxide emitted into the atmosphere. This leads to generating greenhouse gas effects and as a consequence a significant global warming effect. The depletion of fossil fuels and the environmental problems connected with their use implies a change towards alternative energy sources and conversion technologies. Fuel cells, one of the alternative energy conversion technologies, are electrochemical devices that convert the chemical energy of a fuel (mostly hydrogen) into electricity. Fuel cells have gained considerable attention in recent years due to their high efficiency and lower emissions compared to well-established power generation technologies. In this thesis, an innovative 0-D mathematical model for anode recirculated SOFC fed with reformate gas mixture was developed. In this regard, a mathematical model was conducted using the parallel circuit approach to include the thermodynamic and electrochemical phenomena. On the other hand, the experimental studies on the SOFCs were performed to obtain the polarization curve and to determine the cell resistance through the electrochemical impedance spectroscopy method. Then, X-ray diffraction and scanning electron microscopy analyses were conducted to investigate the microstructure of the SOFC at the cell level. The developed model was validated through experimental studies conducted at Technical University of Denmark. Parametric studies were performed to assess the effect of operating parameters on the performance of the SOFC. After that, the developed innovative model was integrated with the biomass gasifier model in order to assess the performance of the system thermodynamic point of view. In addition, an optimization study, which is namely Taguchi method, was performed to find the optimum operating parameters of the integrated system in order to maximize the electrical and fuel utilization efficiencies of the integrated system. The results show that the maximum electrical and fuel utilization efficiencies are 0.1945 and 0.6693, respectively. Taguchi method gives the dominant operating parameters as the operating temperature of the gasifier and pressure ratio of the blower.