Comparative analysis of metal oxide nanoparticle accumulation in landfill gas engine combustion chambers: Insights from three sites

• Published in: Waste management (Elmsford) 2025-01, Vol.191, p.147-159
• Main Authors: Östürk Sömek, Özge, Yıldız, Fikret, Sevimoğlu, Orhan
• Format: Article
• Language: English
• Subjects: Accumulation mechanism; Air Pollutants - analysis; Deposit; Engine combustion chamber; Landfill gas; Metal Nanoparticles - analysis; Metal Nanoparticles - chemistry; Metal oxide; Metals - analysis; Organometallic compounds; Oxides - analysis; Oxides - chemistry; Siloxanes; Waste Disposal Facilities
• ISSN: 0956-053X; 1879-2456; 1879-2456
• DOI: 10.1016/j.wasman.2024.11.003

•Impacts of LFG impurities and oil additives on deposit formation in engine combustion chamber.•Role of organometallic compounds containing S, Si, Sb, Sn, and P in deposit formation.•Cross-sectional analysis to reveal non-uniform elemental distribution in engine deposits.•Impact of deposit formation in engine combustion chamber on the deterioration of lube oil quality.•Identifying the most effective mechanisms contributing to deposit formation in LFG engine. Combustion chamber deposits adversely affect the operating performance of gas engines. In this study, the elemental composition of deposit samples collected from the inner surface of combustion chambers in gas engines across three different facilities was examined using various methods. The proportional changes in metal oxides along the internal cross-sectional surfaces of the deposits were examined to depict the deposit formation process from beginning to end. Additionally, the study investigated the identification of metals accumulated in the engine oil, their contribution to deposit formation, and the accumulation mechanisms of metal oxide nanoparticles on the engine’s interior metal surfaces. The main elements identified in the deposits from the Odayeri and Kömürcüoda facilities were Si, S, and Ca, whereas deposits from the Dilovası facility contained Si and Sb. These major elements, identified by SEM-EDS, were confirmed through XRF analysis. XRD analysis further confirmed the presence of Ca and S as CaSO4 crystals in the deposits. Ca originates from additives used to increase the total base number of engine oil and control the corrosive effects of landfill gas. It has been determined that silicon accumulates in engine oil over time. An important finding is that metal oxides in the combustion chamber primarily accumulate through impaction, sticking, and thermophoresis mechanisms.