Preliminary experimental study of butanol electrosprays for power generation

The possibility of producing butanol efficiently with the use of fermentation processes has been recently demonstrated. This could potentially lead to the production from renewable sources of a fuel that has energy density significantly increased with respect to the currently widely used ethanol. We provide preliminary experimental results on the structure of butanol electrosprays (droplet size and velocity measurements with Phase-Doppler Anemometry) with a particular emphasis on the determination of the dependence of droplet size on mass flow rate and applied electric field. In parallel, a comparison is provided with the electrosprays of low conductivity fuels for which data are available from previous published studies. These preliminary results show significant differences from low-conductivity fuel electrosprays that practically produce monodisperse aerosols, the droplet size of which can be controlled by spray flow rate. This is a strong indication that the "cone jet" mode that has been used extensively with hydrocarbon electrosprays may not be sustainable for butanol sprays. The results are rationalized in terms of an experimental study of the dependence of butanol conductivity on applied voltage.