FILTERABILITY OF DISTILLATE FUELS. PART 2. EFFECT OF FUEL VISCOSITY AND RELATED FACTORS

Abstract : Studies of additional factors influencing filterability of distillate fuels further substantiate the utility of a constant-head gravity-flow method for rating filterability. Quantitative relationships were made possible by selecting filter papers of uniform porosity. It was shown that the filterability of a distillate fuel contaminated by a given amount of sediment is directly proportional to the fuel viscosity. The effect of temperature on filterability was proven to be due to the variation of viscosity with temperature. Filterability is also directly proportional to the fuel pressure (head) on the filter. It was shown that variations in filter porosity could be balanced by proper adjustment of fuel head. No significant change in fuel viscosity was found due to aging, either normal or accelerated. It is proposed, therefore, that changes in fuel filterability due to aging are due to accumulation of insoluble residues in the fuel. (Author)