Energy, exergy, economic and sustainability assessments of a compression ignition diesel engine fueled with tire pyrolytic oil - diesel blends

Every year, millions of tons of tire become unusable around the world and waste tire dumps threaten human health and the environment. Therefore, recycling of waste tires has attracted attention recently. In this study, energy, exergy, economic and sustainability analyses of a compression ignition diesel engine fueled with tire pyrolytic oil-diesel blends were performed and the results were compared with that of neat diesel. Tire pyrolytic oil was produced from waste tires with vacuum pyrolysis technique. Hydro-sulfuric acid treatment, vacuum distillation and oxidative desulfurization processes were applied to reduce emission values of tire pyrolytic oil. Tire pyrolytic oil was blended with neat diesel as 10 vol% (TPO10D90), 30 vol% (TPO30D70) and 50 vol% (TPO50D50). The test engine was single-cylinder, four-stroke, naturally aspirated, compression ignition diesel engine and the experiments were conducted for different test engine loads of 3 Nm, 6 Nm, 9 Nm and 12 Nm at constant crankshaft speed of 2000 rpm. The highest energy and exergy efficiencies were obtained for TPO10D90, while the lowest ones were obtained for neat diesel. At 12 Nm, the energy efficiency of test engine was obtained to be 26.89% for neat diesel and 28.15% for TPO10D90, while the exergy efficiency of test engine was found to be 25.19% for neat diesel and 26.36% for TPO10D90. The energy loss per capital investment cost was obtained to be 0.87 x 10(-4) kW/$ for TPO10D90 and 1.03 x 10(-4) kW/$ for neat diesel at 3Nm. At 12 Nm, the highest sustainability index was determined to be 1.358 for TPO10D90, while the lowest sustainability index was 1.337 for neat diesel. Results showed that TPO10D90 had better performance at each test engine load in terms of energy, exergy, economic and sustainability and the increase in tire pyrolytic oil content of blend made the results worse but better than neat diesel. As a conclusion, it can be said that tire pyrolytic oil production from waste tires is important fact from the viewpoint of both waste management and protection of fossil fuel resources depletion. (C) 2020 Elsevier Ltd. All rights reserved.