Specific and Cumulative Exhaust Gas Emissions in Micro-Scale Generators Fueled by Syngas from Biomass Gasification

Abstract

Climate change, environmental degradation, and biodiversity loss are prompting production systems to shift from a fossil-based economy to a circular bio-based one. In this context, biomass gasification is a promising alternative to fossil fuels that can contribute to power generation in rural communities and remote areas as well as provide a sustainable source of energy for developed countries. In this work, exhaust gas emissions (CO, NOx, and SO2) of two syngas-fueled micro-scale generators were measured. The first system is a commercial biomass gasifier genset, whereas the second is composed of a laboratory-scale gasifier prototype and a portable petrol generator. For this second facility, emissions were measured both running on gasoline and on syngas. The comparison was performed both on the pollutant concentration and on their cumulative amount. This comparison was made possible by calculating the exhaust gas flow by knowing the combustion stoichiometry and fuel consumption. The results showed a much lower pollutant concentration running on syngas compared to gasoline. In particular, considering the best configurations, every cubic meter of exhaust gas released running on syngas contains about 20 times less CO and almost one-third less NOx compared to gasoline. Moreover, the cumulative amount of emissions released was also considerably lower due to the lower exhaust gas flow (about 25%) released running on syngas.