Experimental Study on Application to Diesel Generator of Waste Plastic Decomposition Oil ‒ Influence of Addition Waste Edible Oil for Waste Plastic Decomposition Oil

Abstract

A feasibility study was conducted to check whether waste plastic decomposition oil (WPDO) could be used for diesel engines. About 10 million tons of waste plastics are discarded every year in Japan, 83% of which are recycled. Thermal recycling is particularly common, but it has a low energy yield because of the need for transport to incineration plants. Given this, expectations are growing for the use of Waste Plastic Decomposition Oil (WPDO) as a fuel for a new thermal recycling method. However, the problem is that WPDO has low kinematic viscosity and that it is difficult to burn it when using it as a diesel fuel. In order to explore the possibility of using WPDO blended with waste edible oil, this study investigated its effects on engine performance and exhaust emission characteristics. The study used WPDO with its blend ratios of waste edible oil 10%, 20% and 30% respectively, and burned these oils in a conventional 320-cc diesel engine. The engine load was set in five stages by a dynamometer, and maximum load was set at continuous rated output of the test engine. Exhaust gas was sampled directly from an exhaust pipe to accurately measure smoke density using an opacity meter. The study also utilized an exhaust gas analyzer to gauge the level of exhaust emissions, such as CO, CO2, O2, total hydro carbon (THC) and nitrogen oxides (NOx), that were taken directly from exhaust gas samples. The study also investigated engine performance, including brake specific fuel consumption (BSFC). The results found that smoke emissions when WPDO was used were lower compared to the case of gas oil, but they increased when WPDO blended with waste edible oil was utilized. Similarly, NOx emissions were lower when WPDO was used in comparison with gas oil, but they reached the level of gas oil when blended oil was used. However, when it comes to BSFC, WPDO marked the highest figure after it was improved by mixing waste edible oil. Since NOx and smoke emissions tended to increase when the blending ratios were 20% and 30%, the study concluded that the 10% blending ratio is considered to be most ideal.