Ocean-going ships burn heavy fuel oil. The combustion of heavy fuel oil in marine diesel engines emits nitrogen oxides, sulfur oxides, and particulates into the air. Growing public concern over air quality has led to increased scrutiny of heavy fuel oil as a source of air pollutants, with calls for greater regulation of its composition to safeguard public health and the environment. Heavy fuel oil is a complex mixture, prepared by blending residual oil from petroleum distillation with more volatile fractions to meet industry standards. The fuel composition has a significant effect on the type and amount of combustion products produced, but the complexity of heavy fuel oil blends has hindered past efforts at analysis. The advanced distillation curve (ADC) method was developed as a complex fluid analysis protocol, combining thermophysical and chemical properties measurement. We applied the ADC method, under reduced pressure, to a sample of IFO 380 intermediate fuel oil to characterize its volatility and composition as a function of volume fraction. Applying the analytical method to heavy fuel oil yields quantitative data that can be used to model and design more efficient internal combustion engines for ocean-going ships, improving maritime fuel economy while reducing the amount of harmful pollutants released into the atmosphere.

In this paper, we apply the composition explicit distillation curve method to mixtures of JP-8 with hydroprocessed aviation fuels made from camelina (a genus within the flowering plant family Brassicaceae), from castor seed (Ricinus communis), and from waste brown grease used with the Fischer–Tropsch process. For the camelina fuel, the departures (with respect to JP-8) in volatility and in enthalpy of combustion are significant for mixtures with 25 and 50% (v/v) in JP-8. Mixtures with only 10% camelina fuel (v/v) show relatively minor departures. In all cases, the departures (with respect to JP-8) are to lower temperatures (higher volatility) and lower molar enthalpy of combustion. Mixtures of castor based fuel with JP-8 show essentially no departures in volatility or molar enthalpy of combustion up to the 40% distillate volume fraction. Subsequent to this distillate volume fraction, departures are very apparent, with mixtures showing lower volatility and higher molar enthalpy of combustion with higher volume fractions of castor based HRJ. Mixtures of the brown grease based fuel show departures to lower volatility and to higher molar enthalpy of combustion (with respect to JP-8) as the volume fraction of the brown grease SPK increases.

Additive packages are used with aviation kerosenes to achieve performance enhancements, such as higher or lower operating temperatures or increased lubricity. An additive that is used to increase operating temperatures for heat sink applications is the +100 additive that is added to JP-8. As part of a large effort on the characterization of JP-8, we measured the effect of the +100 additive on the volatility of JP-8 by use of the composition-explicit or advanced distillation curve approach. We found that the vaporization temperatures increased modestly in the early stages of the distillation but the difference disappeared after the 70% distillate fraction. We tracked selected components of the additive through the distillation curve and related the concentration to the temperature data grid. This allowed us to determine that the heaviest components of the additive are concentrated late in the distillation curve and a significant quantity in the recovered residue. Still incomplete is our understanding of the role and disposition of the oligomer component of the +100 additive. However, some preliminary viscosity and density measurements are provided to suggest what the fate of this component might be.