THE LOW-TEMPERATURE HANDLING OF NAVY DISTILLATE FUELS Phase Ⅲ The Effect of Pour-Point-Depressant Additives on Cloud-POINT AND Low-Temperature Fluidity

摘要

The effect of six commercially available pour-point depressant additives on the cloud-point temperatures and 'Enjay Fluidities' of six distillate fuels was determined. Five of the six fuels were Navy Distillate types, the sixth was a Diesel Fuel, Marine. The pour-point depressants had no apparent effect on the cloud-point temperatures of the fuels. Minimum safe operating temperatures, above which the fuel is free of solid wax, cannot be predicted from pour-point measurements if pour-point depressants are allowed in the fuel. The pour-point depressants lowered the critical Enjay Fluidity temperatures but not as effectively as would be indicated by the pour-point temperatures. The critical Enjay Fluidity data indicate that fuel-flow problems may occur at higher temperatures than indicated by the pour point if pour-point-depressant additives are present. An analysis of the Enjay Fluidity procedure leads to the conclusion that the procedure is more indicative of the 'slumpability' of a fuel to a pump suction than it is of the action of the fuel downstream from a pump discharge. It is recommended that the Enjay Fluidity procedure be used in lieu of the pour point to ensure that fuels reach pump suctions at low temperatures if pour depressant additives are used. A procedure indicative of the fuel 'pumpability' characteristics is needed. (Author)