Rheological Characterization of Animal Fats and Their Mixtures with No. 2 Fuel Oil

The rheological properties of biomass fuels based on waste animal fats and their mixtures with petroleum-based fuels were determined. Viscosities and densities of white pork fat, poultry fat, beef tallow, and yellow grease were measured to weigh their potential use as fuel substitutes and additives. Viscosities of 30% mixtures of these fats with No. 2 fuel oil were also documented. Psuedoplastic flow behavior was indicated for all products, with increasingly Newtonian behavior at higher temperatures and shear rates. Mixtures displayed rheological properties similar to those of pure fuel oil, implying that using these oils at an additive level may be effective for extending fossil fuel supplies.