Impact of 50% HRD-76 on Middle Distillate Fuel Filtration and Coalescence

Hydroprocessed renewable F-76 (HRD-76) is derived from non-petroleum sources. HRD-76 utilizes a renewable feedstock of biomass derived oils. The Navy is in the process of qualifying a 50%/50% (by vol.) F-76/HRD-76 blend for use as an alternate to 100% petroleum derived F-76. In order for 50%/50% F-76/HRD-76 blend to be considered a drop-in replacement for petroleum derived F-76, the 50%/50% F-76/HRD-76 blend must be compatible with all current fuel system components including filter/separators. The single-element test (SET) is a fit-for-purpose test that evaluates the compatibility of new additives and fuel compositions with filter/separator systems currently in use by the fleet. The SET evaluates the ability of filter/separators to remove solid contaminant levels of 72 mg/gal and water levels as high as 30,000 ppm. By measuring the concentration of contaminant in the effluent fuel stream, the impact of the 50%/50% F-76/HRD-76 blend on the filter/separator's performance can be determined. A 50%/50% F-76/HRD-76 blend was found to have no negative impacts on filter/separator performance. No effluent samples exceeded the effluent free water concentration limit established in Chapter 541 of the Naval Ships' Technical Manual (NSTM) of 40 ppm for free water. No effluent sample exceeded a sediment concentration of 5.0 mg/L and the average sediment concentration measured during the solid injection phase was 0.44 mg/L. The original document contains color images.