Waste-To-Power: Assessment of Refuse-Derived Fuel use in a Gasification Plant in the Brazilian context

Abstract

In the past 10 years, Brazil’s government has been investing in alternative sources to decrease the high dependence of the electricity grid on hydropower plants, mainly due to a constant decrease in pluviometry levels. A promising fuel in the context of the circular economy is refuse-derived fuel (RDF), which is the combustible fraction of Municipal Solid Wastes. It has high calorific power, low levels of hazardous components, and is a more homogeneous material. Moreover, RDF is an abundant, secure source of fuel with a market price nearly independent of external currencies. As gasification is a common Waste-To-Power (WTP) technology used worldwide, this work evaluated the electricity generation by this technology on a small scale (200 kW), using air as a gasifying agent and gas turbines, and according to Brazilian legal requirements regarding the composition of RDF. The process was simulated in Aspen Plus v8.6 for an RDF with an LHV of 15.9 MJ/kg. Sensitivity analysis on key operational parameters showed that for the representative composition of RDF in Brazil, an ER between 0.1-0.3 would be suitable for a gasification process, resulting in a net electrical efficiency of 22-27%.