Technical analysis of hydrogen-rich stream generation through CO2 reforming of biogas by using numerical modeling

A well-known and widespread method for producing a hydrogen-rich gas stream consists of reforming processes that convert a hydrocarbon, by adopting a substance, usually steam, to act as reforming promoter. CO2 dry reforming allows the use of CO2 as a reforming agent, which appeals owing to the undeniably negative environmental impact of CO2. This technology opens up interesting perspectives in the field of energy and environmental sustainability since it offers reintegration of CO2-rich gas streams into reforming processes as well as conversion of hydrocarbon. In this context biogas can be used exclusively as it consists mainly of CH4 and CO2, which is environmentally sustainable as gas generated from originally pollutant organic waste. The paper reports a wide performance analysis at the possible and different operating conditions by using a numerical simulation model of a CO2 dry reforming of biogas, set up ad hoc in Matlab. The numerical simulations are conducted in relation to the main control parameters such as the CO2/CH4 ratio, pressure and temperature. Hydrogen yield and feeding gas conversions are taken into account for the performance testing, while the assessment of safe operation involves consideration of the activities causing carbon deposition. The paper aims at performing several parametric energy and technical analyses to assess the various outcomes in order to acquire an important tool for choosing more favorable functioning in relation to possible uses. (C) 2015 Elsevier Ltd. All rights reserved.