Effect of water injection on diesel particles agglomeration

Diesel exhausts constitute one of the main aerosol sources of fine particles to the environment. The characteristics of these particles make conventional filtration methods not efficient enough to remove them. Diesel engine exhaust particles primary consist of soot (carbonaceous nuclei) and organic volatile compounds, which have been adsorbed over their surfaces. These particles grow by coagulation into chainagglomerates (Kittelson, et al, 1979). The agglomerates have larger surface than primary particles and are electrically charged by electrons and ions produced by chemical reactions (patschull, et aI, 1992). These properties may favour the adsorption and chemical reactions of vapours and gaseous compounds on the surface of the particles, so any change in the physical and chemical composition of the gaseous phase might produce significant variations in the particle characteristics. To use the agglomeration process as a previous stage in the gas filtration process, a study to determine the effect of water injection on diesel exhaust particles have been performed.