Real-Time characterization of particulate matter emissions from HVO- blended diesel using an integrated multi-instrument approach

This study investigates diesel particulate matter (DPM) emissions from a 7 V/V% hydrotreated vegetable oil-diesel fuel blend (HVO7) compared to conventional diesel (B0) using a novel integrated real-time measurement system. The methodology combines photoacoustic spectroscopy, particle sizing, thermal treatment, and gas analysis to provide comprehensive, in-situ characterization of diesel particulate matter across various flue gas temperatures of different engine loads. This approach enables simultaneous assessment of particle size distributions, optical properties, and gas-phase emissions, overcoming limitations of traditional single-instrument methods. Results show that HVO7 reduces particle number concentrations, particularly under low-load conditions, while producing larger particles than B0, with reductions diminishing at higher engine loads. HVO7 exhibits lower black carbon emissions and varying organic matter content, influenced by operating conditions. Optical absorption measurements reveal distinct behavior, with HVO7 showing greater sensitivity to operational changes. A strong correlation between gas-phase nitrogen oxides and aerosol optical properties highlights a novel link, enhancing emission characterization. The proposed integrated methodology offers a robust framework for real-time DPM analysis, and the findings underscore the potential of HVO to mitigate PM emissions, contributing to sustainable fuel development and emission control strategies.