Combustion of Emulsions in Internal Combustion Engines and Reduction of Pollutant Emissions in Isolated Electricity Systems

The aim of this work is the combustion of emulsions in two internal combustion diesel engines, instead of residual fuel oil, to reduce pollutant emissions into the atmosphere and fuel consumption for a cleaner energy transition. A methodology was designed that include the planification and implementation of several experiments in a thermoelectric power plant in Madeira Island, that is part of an isolated electricity production system. In the first place, the planification of experiences was developed and the reference points were created. In this case study, three different operating regimes at the nominal speed of 500 rpm were studied: 7.5 MW, 8.5 MW and 9.5 MW, with a gradual increase of the incorporation of water into the emulsions. A comparative analysis of the potential emulsions in diesel engines, instead of fuel oil, were carried out and two process solutions were created in the 8.5 MW regime with 15% v/v of water and 18% v/v of water. The impact on process parameters and the savings obtained were measured. The best result obtained was the reduction of 56.5% of CO, 96.7% of NO2 and 4.2% of NOx emissions. The specific fuel consumption savings obtained were 2.7%. In conclusion, the experiments and research developed contributed to a more in-depth knowledge about the potential of emulsions in combustion systems; pollutant emissions were reduced; and we designed a new operation regime for the internal combustion engine that are part of an isolated electricity production system.