Life Cycle Environmental Impact Evaluation of Newly Manufactured Diesel Engine and Remanufactured LNG Engine

The application of Liquefied Natural Gas (LNG) in vehicles is considered to be an important way to solve the energy and environmental problems. In China, many waste diesel engines are beginning to be remanufactured to LNG engines. In this study, a life cycle assessment is carried out to quantify the energy saving and environmental emission of a remanufactured LNG engine and newly manufactured diesel engine, both engines are compared by means of material usage, cumulative energy requirements and environmental emissions over the entire life. The results show that, compared with diesel engine newly manufacturing, LNG engine remanufacturing could reduce 42.62% of primary energy demand (PED); the environmental impacts reduction of acidification potential (AP) and nutrient enrichment potential (EP) could reach to 69.61% and 71.34%, which are most distinct; global warming potential (GWP) and photochemical ozone formation potential (POCP) can be reduced by 46.42% and 43.90% respectively.