Biomass-derived fuels are emerging alternatives to fossil fuels because of their renewability and better carbon balance. Fuel researchers from Zhejiang University have developed and improved a catalytic method of converting rice husk to biofuels mainly composed of ethanol, ethyl acetate, and acetone. Optimization of the catalytic production process so that the final fuel has good combustion characteristics is something that requires detailed investigation. This study evaluates the laminar burning features of two fuels produced by the catalytic reaction. These two fuels are ETEAAC211 and ETEAAC121 (ETEAAC211, 50 vol % ethanol, 25 vol % ethyl acetate, and 25 vol % acetone; ETEAAC121, 25 vol % ethanol, 50 vol % ethyl acetate, and 25 vol % acetone). The experiment was conducted in outward propagating spherical flames at T0 of 358 K, P0 of 0.1 MPa, and equivalence ratios (ϕ) of 0.7–1.4. Moreover, the flame intrinsic hydrodynamic and thermal diffusion instabilities are assessed and discussed. It was noticed that the peak laminar burning velocity of the fuels occurred at ϕ of 1.1. The hydrodynamic instability reached its peak at ϕ of 1.1 as a result of the thin flame thickness and the high density ratio of burned/unburned mixtures. The Markstein length decreased with the equivalence ratio. However, the Markstein length decreased below zero at ϕ of 1.4 for ethyl acetate and ETEAAC121, showing the increased thermal diffusion instability as the equivalence ratio increases.
Bibliographical notedoi: 10.1021/acs.energyfuels.8b01440
Xu, C., Zhou, K., Li, X., Zhong, A., Oppong, F., Wang, H., ... Wang, C. (2018). Laminar Burning Characteristics of Two Rice-Husk-Derived Biofuels. Energy & Fuels, 32(9), 9872-9882. https://doi.org/10.1021/acs.energyfuels.8b01440