Safety Characteristics of Ethanol/Automotive Petrol Mixtures

摘要

Triggered by new developments in the composition of ethanol/petrol fuels (ethanol content >85 vol%) additional measurements of the maximum experimental safe gap (MESG) have been carried out.The aim of the work was to identify the ethanol concentration in the liquid mixture for which the MESG (determined at a vapour/gas mixture temperature of 50°C) becomes 0.9 mm and lower.The vapour phase composition used for these determinations was the equilibrium composition over the liquid fuel mixtures at 50°C.The liquid mixtures were prepared from respective amounts of volumes of petrol and ethanol (uncertainty of volume measurement 0.1 vol% absolute).The automotive petrol fuels used for this purpose were of unleaded petrol super grade summer quality (Eurosuper ROZ 95) which are commercially available and had a Reid vapour pressure between 580 mbar and 595 mbar (EN 228 [1]:climate zone A).For conservative conditions,summer quality was chosen because of its lower vapour pressure compared to winter quality.