Identification of major and minor elements by multiple analysis responsible for deposit formation on engine utilizing landfill gas

Abstract

Combustion chamber deposits cause numerous undesirable negative effects on gas engine performance. The purpose of this study was to understand the morphological structure of deposit surface and to determine the major and minor elements of the chemical composition of the deposits formed on the surface of the combustion chamber of the reciprocating gas engine utilizing landfill gas (LFG). The morphological structure of deposits was analyzed by scanning electron microscopy (SEM) that revealed that the bottom surface displayed more smooth and noticeable cracks and in contrast to the top surface, demonstrated more irregular and wavy surface with adhesion of different size and shaped nanoparticles. On the other hand, the following crystals; CaSO4, (Fe+O)-O-3 (OH), FeSO4 and CaSO4 center dot 2H(2)O were determined in the deposits by X-ray powder diffraction (XRD) for the first time. Besides, the Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES) and X-Ray Fluorescence (XRF) analysis confirmed that the mass ratios of Si, S, Ca, Sn were high above 2% in both analyses that measured 25 elements in all samples. The energy dispersive spectroscopy (EDS) spectrums represented the dominant peaks of Si, S, Ca, Sn as well. The results revealed that Si, S, Ca and Sn emerged as the main elements of the deposits in the application of three elemental analysis methods.