Year-round biodiesel use strategy in diesel engines in Canadian adverse cold weather conditions

Abstract

The effects of climate change that have been seen at an unprecedented scale over last decade or so, have sparked intensive efforts toward the identification and development of clean, environmentally compatible, and renewable fuels. Biofuels such as alcohol and biodiesel have been identified as alternatives for powering internal combustion engines. When using vegetable oil as a feedstock for the production of biodiesel, major issues that arise include its poor low temperature properties. In this study, an experimental analysis was conducted to test the feasibility of biodiesel in cold climates specifically in Thunder Bay region and to suggest an appropriate solution for the biodiesel usage throughout the year. Weather reports from last decade were studied to compare with the cloud points of biodiesel blends. Biodiesel was produced from canola oil from transesterification and fractionation processes. Summer diesel and winter diesel have been used as reference fuels. Five different fuel series were used. The first series was summer diesel-biodiesel with ten blends (SB10, SB20, SB30, SB40, SB50, SB60, SB70, SB80, SB90 and B100). The second series was winter diesel-biodiesel with ten blends (WB10, WB20, WB30, WB40, WB50, WB60, WB70, WB80, WB90 and B100). The third series was winter diesel-biodiesel with 2 volume percent of (cold flow additive) Wintron Synergy series (WB20S2, WB50S2 and B100S2). The fourth series was winter diesel-fractionated biodiesel (FB20, FB50 and FB100). The final was winter diesel-fractionated biodiesel with 2 volume percent of Wintron Synergy series (FB20S2, FB50S2 and FB100S2). Except for winter diesel-biodiesel with 2 vol% synergy, all the fuel blend series were tested on two separate diesel engines; a four-cylinder heavy-duty diesel engine at constant speed of 800 rpm for emissions at idling condition followed by a two-cylinder light-duty diesel engine to investigate effects of fuel blends on performance and emission, under low, medium and high loads, at variable engine speeds of 1000 rpm, 2100 rpm and 3000 rpm. Results showed that normal biodiesel and fractionated biodiesel with 2 vol% synergy showed significant improvement in the cloud point. FB40S2 has the lowest cloud point compared to other fuel blends measuring -48.5⁰C. The effect of fuel blends on engine performance in light duty engine was investigated. The emissions of carbon monoxide (CO), hydrocarbon (HC), oxides of nitrogen (NOx) and smoke opacity from different fuel blends were measured and compared to summer and winter diesel fuels. In both the engines, fractionated biodiesel and synergy blends were found to be effective in reducing both CO and HC emissions. Smoke opacity emissions when compared from both the engines had a contrasting results. However, all biodiesel blends increased NOx emission. Results indicated that fractionated biodiesel with 2 vol% synergy had better engine performance, and lower emission compared with diesel fuel and normal biodiesel blends. Thus, fractionated biodiesel up to 80 vol% with 2 vol% synergy was found to be suitable for use in diesel engines in extreme winter conditions in Canada without the need for any engine modification.