Soot and Gaseous Emissions Characterization of Butyl-Acetate/Diesel Blend in a Heavy-Duty Engine 2023-01-0267

Significant effort has been put toward developing future-generation biofuels aimed at either spark-ignition or compression-ignition engines. Butyl-Acetate (BA), C₆H₁₂O₂, is one such fuel that may be viable as a soot reduction drop-in blend candidate without significant impact on performance or efficiency. Though BA does have a low CN (≈ 20) and heating value (27 MJ/kg), it offers promise as a drop in blend-candidate with pump diesel due to its improved cold weather performance, high flash point, and potential for high volume renewable production capacity.

This work investigated the impacts of 5% by volume blend of BA and standard pump diesel (DF2) on overall performance and with a particular focus on soot behavior. Tests were completed at 13 operating points spanning the operating map including full power. Results show a significant reduction in soot without significant impact on NOx emissions and minimal impact on thermal efficiency. Of course, BSFC increases due to the reduced heating value but does not have a noticeable impact on ECU operating set-points or resulting in-cylinder combustion-related parameters. Ultimately, despite decrease in global oxygen-to-fuel ratio with BA blend and no clear changes to combustion or control behavior, soot concentration is reduced by an average of 30%. The potential impact on regeneration cycles for the soot particulate filter enabled by this soot reduction represent clear opportunity for corresponding reduction in total fuel consumption for operators.