Ecological influence of addition of antioxidant and incorporation of selective catalytic reduction on NO emission in off-road engines powered by waste plastic oil blend

摘要

Accumulation of waste plastics and their disposal have been a perennial problem across the globe and conversion of waste plastic into useful fuel could solve the global problems of environmental pollution and fast depletion of fossil reserves. Emissions control in internal combustion engines can be achieved through fuel modification, engine modification, or by tailpipe gas treatment. The concept of tailpipe gas treatment is comparatively easier owing to a little or no engine modification requirement and one among them is selective catalytic reduction (SCR). In the present study, an attempt has been made to control NO emission of a plastic oil-fuelled Cl engine through fuel modification as well as exhaust after-treatment technique. Waste plastics have been converted to plastic oil (PO) through pyrolysis process and investigation has been carried out in a four-stroke, mono barrel diesel engine fueled with diesel-PO blend (50:50), added with antioxidant phenylenediamine. The engine is incorporated with the SCR technique through the injection of water urea solution in the tailpipe at 0.2 lit/min to examine the engine performance and NO and other emissions reduction potential. The test results revealed that oil generated through waste plastic could be a good substitute to fossil diesel, and the combined effect of antioxidant addition and incorporation of the SCR technique is very effective in reducing NO emission to the tune of 66% without much compromise in the engine brake thermal efficiency.