Optimizing dual fuel engine performance with hydrogen-enriched syngas from co-pyrolysis of biodegradable and non-biodegradable wastes

Abstract

This study explores the production of hydrogen-enriched syngas from waste groundnut shells and waste milk covers through a catalyst bed-based co-pyrolysis process. The objective was to develop an efficient method for producing high-quality syngas, enhancing its hydrogen content, and evaluating its performance as a fuel in a compression ignition (CI) engine. The experimental setup involved co-pyrolysis at temperatures between 550 °C and 600 °C using Ni/Al₂O₃ and La/Al₂O₃ as catalysts. Gas chromatography analysis revealed that Ni/Al₂O₃ catalyst produced syngas with a hydrogen concentration of 38.28 % and a total yield of 68 %, while La/Al₂O₃ resulted in 35.45 % hydrogen with a 65.2 % yield. The CI engine tests demonstrated improved brake thermal efficiency (BTE) in dual fuel mode, reaching 32.20 % with hydrogen-enriched syngas, compared to 30.98 % with syngas without hydrogen enrichment. Specific fuel consumption (SFC) was reduced to 0.28051 kg/kW-hr. Emission analysis showed significant reductions in hydrocarbons (HC) and carbon monoxide (CO) emissions, though nitrogen oxide (NOx) emissions increased. The study concludes that hydrogen-enriched syngas, produced from waste materials, is a viable alternative fuel, offering enhanced engine performance and lower environmental impact, despite the challenge of increased NOx emissions.