Engineering Economic Analysis of Using Liquefied Petroleum Gas in Diesel Engine for Sand Digging and Scooping Industry

Abstract

The engine systems and accessories suitable for application of liquefied petroleum gas (LPG) with diesel engines for sand digging and scooping industry is the engine fuel system with LPG and diesel oil fumigation system. The system started its ignition with diesel fuel, and then gas will be attracted into the combustion chamber through the intake pipe after blending with regulator. The results shown minimum fuel cost per volume of sand were 16.30 baht per cubic meter which produce 37.8 cubic meter of sand per hour. Total fuel costs were 616.21 baht per hour. For liquefied petroleum gas used was 105.33 baht per hour, representing gas used was 5.39 kilograms per hour. For diesel oil used was 510.89 baht per hour, representing diesel oil used was 17.7 liters per hour. The economic study with new fuel system costs decreased 19.76 baht per cubic meter from 36.06 baht per cubic meter. The break-even volume was 1,283.37 cubic meters of sand. Payback period is equal to 5.8 days, so the modified engine with combined fuel system for sand digging and scooping industry has economic value.