Investigation of the Combustion, Emissions, and Engine Performance Characteristics of Cottonseed Biodiesel for use in Power Generation

This study investigates the combustion characteristics of cotton seed FAME (C100 and C20), in a direct injection diesel engine. The research compares the combustion and emissions characteristics of cotton seed FAME to ultra-low sulfur diesel #2 (ULSD#2) to investigate possible use in a startup boiler to produce steam for large boiler operation, and for use in diesel engine generators. Fuel properties including viscosity, oxidation stability, lower heating value, thermo-gravimetric and differential thermal analysis, and spray characteristics were analyzed. Fuel property measurements were comparable to ULSD#2 in every aspect except oxidation stability which showed the C100 being stable for a shorter period of time. Mechanical efficiency of ULSD was 83% and presented a 5% decrease for C100; while the overall efficiency was 36% for ULSD and 33% for C100 at 8 bar IMEP. The NOX for C100 was improved and presented an 11% decrease compared with ULSD. Unburned hydrocarbons value (UHC) for ULSD was 2.8 g/kWh at 8 bar IMEP, and were improved by 18% for C100. The carbon monoxide (CO) and carbon dioxide (CO2) emissions for C100 was improved with a 17% reduction compared with ULSD at 3 bar but were relatively constant at 8 bar IMEP, presenting a value of 0.82 g/kWh for both fuels. The soot value for ULSD was 1.5 g/kWh and presented an improved 42% decrease for C100 at 8 bar IMEP. The results suggest a very good performance of cotton seed biodiesel, even at very high content of 100%, especially on the emissions side that showed decreasing values for regulated and non-regulated species