Global warming and energy crisis are the main issues humanity has to deal with in the forthcoming years. Biomass technology offers a suitable solution for energy production and can make significant greenhouse gas emissions savings compared to fossil fuels. However, further improvement regarding the decrease of CO2 emissions to make full use of biogas can be achieved by converting the CO2 contained in the biogas into bio-chemicals rather than being simply discharged into the atmosphere.
The aim of this work is to analyze the performance of a novel process for CO2 and CO conversion into acetic acid (AA). Firstly, the biogas converts into bio-syngas through reforming and Water Gas Shift (WGS) steps with controlled H2-to-COx ratio. From there, several applications can be taken under consideration as syngas is among the most widely used primary materials in the chemical industry. The main concept will provide a syngas with H2-to-CO ratios well above the ones required for the AA synthesis. Excess hydrogen is used to provide energy to the system using a hydrogen-fueled SOFC (Solid Oxide Fuel Cell) coupled with heat recovery from exhaust air at the cathode to provide the necessary heat to the reformer. Thus, resulting in a self-sustainable system. Aspen Plus™ was used to create a steady state model of the global process. Afterwards, a parametric study was carried out to investigate the effects of some operating conditions on the overall performance. Effects of fuel utilization factor and current density on the SOFC performance were also evaluated.