Feasibility of running a micro gas turbine on wood-derived fast pyrolysis bio-oils: Effect of the fuel spray formation and preparation

This study examines the feasibility of using fast pyrolysis bio-oil (FPBO) made from non-food woody biomass in a micro-gas turbine with a unique burner design, motivated by the recent surge in the development of renewable carbon-neutral biomass-derived liquids in energy applications. The study is comprehensive and covers FPBO production and applications, physicochemical properties and spray characteristics, and combustion performance. The effects of fuel spray formation and preparation on the combustion of FPBO, ethanol (EtOH) and diesel fuel were investigated using two twin -fluid nozzles with distinct atomization mechanisms, externally-and internally-mixed, and a premixer tube. In contrast to diesel fuel and EtOH, reaching a stable flame using 100% FPBO was impossible because of the fuel polymerization (or coking) when impinging on the high-temperature inner wall of the premixer tube. EtOH addition was, therefore, used to address the problem by improving the FPBO's volatility. The FPBO spray flame generated by the internally-mixed nozzle exhibited less gas-and solid-phase emissions than the externally-mixed one and required less EtOH addition for stabilization. While this study shows the feasibility for deployment of FPBO in the present micro-gas turbine design, injector modification or fuel upgrading are necessary prior to it being used to replace fossil oils. (c) 2021 Published by Elsevier Ltd.

Automated summary

This study examines the feasibility of using FPBO made from non-food woody biomass in a micro-gas turbine, showing challenges in achieving stable flame with 100% FPBO due to fuel polymerization, which can be addressed by adding EtOH to improve volatility. The internally-mixed nozzle demonstrated cleaner emissions and required less EtOH addition for stabilization compared to the externally-mixed one. Injector modification or fuel upgrading is necessary prior to the deployment of FPBO in replacing fossil oils.