Gasified Biomass Fueled Hybrid SOFC Based Power Cycle: Impacts of Carbon Monoxide Fraction in Inlet Fuel Available to Purchase

One of the main challenges to use biogas as fuel in hybrid solid oxide fuel cell (SOFC) cycles is variable nature of biogas composition which may cause significant changes in plant performance. On the other hand, carbon monoxide is one of the main components in gasified biomass. Therefore, it is vital to investigate the influences of CO fraction in inlet fuel on the cycle performance. This paper presents the analysis of impacts of carbon monoxide concentration in inlet fuel on the performance of hybrid tubular SOFC and gas turbine (GT) cycle with two configurations, system with and without anode exhaust recirculation. The simulation results are considered when system is fueled by pure methane as a reference case. Then, the performance of the hybrid SOFC-GT system when methane is partially replaced by CO from concentration of 0% to 90% with an increment of 5% at each step is investigated. The proposed model is intended for steady state simulation of hybrid SOFC-GT cycle and is developed in Aspen Plus^®. The system performance was monitored by investigating parameters like SOFC and system thermal efficiency; SOFC, GT, and cycle net and specific work; air to fuel ratio; as well as air and fuel mass flow rate. The results of the sensitivity analysis demonstrate that CO concentration has significant effects on the system operational parameters, such as efficiency and specific work.