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Abstract: Simultaneous combustion of biomass (wood or straw) with coal represents an alternative energy source with economic potential and smaller pollutant emission. Under the current environmental legislation, biomass is seen as a zero emitter of carbon dioxide emissions. The paper analyses the potential corrosion and the formation of adherent deposits in the coal–biomass co-combustion process at two pilot installations. Three types of experiments with a mixture of coal, straw and wood are conducted. For the slagging phenomena, two installations pilot (grate-fired furnace) were used: one of 55kW thermal power and other of 2MW. As a control sample, different types of steels were used. The results can lead to the implementation of measures to reduce the effects of corrosion. The final aim is to increase the boilers efficiency and life duration. Furthermore, the ash analyses allow their use as fertilizer in agriculture. [Copyright &y& Elsevier]

Abstract: One of the main advantages of biodiesel fuels is that almost eliminate carbon dioxide emissions based on the CO2 consumption during plant growth. However it is accepted for most researchers that when burned in diesel engines there is an increase of the NOx emissions when these are compared to the NOx emissions produced by mineral diesel fuel. HCCI with diesel fuel is being considered as an alternative combustion process in the internal combustion engine, mainly because of the huge potential for simultaneous reduction of NOx and soot emissions while fuel conversion efficiency is not compromised, in fact, it is usually increased. The HCCI combustion process can accept a variety of fuel types, like biodiesel and mixtures with mineral diesel fuel. The main reason for burning biodiesel fuel in HCCI combustion mode is that it enables the simultaneous reduction of NOx and soot emissions to current standard requirements, as well as the elimination of CO2. This paper shows a methodology for HCCI combustion mode of biodiesel mixtures based on a high swirl ratio and EGR rate combined with late injection where HRR, NOx, CO, HC and soot emissions have been analyzed. This strategy has reduced fuel wall impingement encountered when early injection is used. Bowl in piston geometry has been designed with a dedicated swirling flow model and a NOx emission of biodiesel fuel has been reduced. [Copyright &y& Elsevier]