Reduction of nitrogen oxides (NOx) using liquefied petroleum gas (LPG) in spark ignition (SI) engine

Abstract

Conventional fuels such as gasoline and diesel are causing serious environmental issues due to their high amount of pollutants. A study was conducted on the use of LPG in conventional two-stroke and fourstroke gasoline engines. The engines were tested using LPG and gasoline so that comparisons of the emissions of pollutant gases and engine performance can be made. The results obtained are very encouraging in the emission aspect. The average reduction of emission gases from the LPG fuel system are 64% for NOx, 31% for CO2 and 57% for CO for the two-stroke engine. The four-stroke engine achieved a reduction of 41% for NOx, 11% for CO2 and 40% for CO. On the other hand, the LPG fuel system also delivered a comparable torque and engine efficiency as compared to gasoline. The results of this research show the high potential of LPG as an alternative fuel for spark ignition engines.