A fuel blend containing 20% so-called ‘propanol-plus’ and 80% SASOL diesel was tested in a 4-cylinder direct-injection diesel engine. The propanol-plus, a mixture of 47% propyl alcohol and 53% higher alcohols, is a by-product of the SASOL fuel-from-coal process, and it would be of tremendous advantage if it could be blended ‘on-the-spot’ with the diesel produced by SASOL.
Performance results with standard injection pump settings indicated that in comparison with operation on pure diesel, operation on the propanol-plus/diesel blend reduced the power by roughly 5% throughout the speed range. In addition, the volumetric fuel consumption was increased by, on average, 5.5% throughout the speed and load ranges.
Despite the harsh combustion conditions created by the poor ignition quality of the propanol-plus/diesel blend, the engine successfully completed 300 hours of a particularly severe durability cycle. The major area of concern was the wear in the fuel injection pump, which was slightly higher than normal.