Environmental and cancer risk potential assessment of unregulated emissions from Methanol-Diesel dual fuel engine

The present study experimentally investigates the effect of engine load and fuel premixing ratio (PMR) on unregulated emission from methanol-diesel dual-fuel RCCI (MD-RCCI) engines. The study focuses on assessing the adverse effects of unregulated emissions (saturated HC, unsaturated HC, carbonyl compounds, aromatic hydrocarbon NH3 and SO2) on the environment and human health. In order to quantify the effect on the environment, the greenhouse gas potential (GWPs), Acidification potential (AP), Eutrophication potential (EP), and Ozone forming potential (OFP) are calculated and presented. To see the effect on human health, the cancer risk potential (CR) of the carbonyl compounds (HCHO and CH3CHO) is calculated and presented. The results demonstrate that at lower engine load, with an increase in PMR the OFP and CR for MD-RCCI operation increase significantly, whereas AP, EP and GWPs decrease. Additionally, with an increase in engine load at a fixed PMR, the AP, EP, and OFP decrease significantly. The presence of low carbon content and inherent oxygen atom in methanol decreases the concentration of main GWPs species such as CO2. MD-RCCI operation emits significantly lower concentration of NOx, and hence AP, EP potential decreases.