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Recently the performance of dual fuel strategy on multi-cylinder engines over the whole engine map has received increasing attention. This research focuses on the potential of Homogeneous Charge Induced Ignition (HCII) combustion fueled with gasoline and diesel meeting Euro V emission standard through the whole operating range using a simple after-treatment system. This combustion mode utilizes a port injection of high-volatile fuel (gasoline) to form a homogeneous charge and a direct injection of high ignitable fuel (diesel) near the Top Dead Center (TDC) to trigger combustion. In this paper, an experimental and numerical investigation of the combustion characteristics and emission formation of HCII on a multi-cylinder heavy-duty engine is conducted. The effects of gasoline ratio ( R g ), one of the most important parameters in dual-fuel mode, are explored and analyzed in detail. A R g of 70–80% is recommended for better combustion and emission performance at the operating condition in this paper. HCII also turns out to be an effective strategy to reduce NOx and soot emissions at the same time. Furthermore, the high THC and CO emissions of HCII combustion can be eliminated using Diesel Oxidation Catalyst (DOC). Then the HCII strategy was optimized through the whole operating range showing a great potential of meeting Euro V limitations only with DOC as an after-treatment device. The fuel consumption also reduced with dual fuel strategy. [ABSTRACT FROM AUTHOR]

Energy is the driving force for growth and per-capita energy consumption is a key parameter for the development of a nation. Carbon dioxide emissions from burning of fossil fuels are the main concerns for global warming. This paper presents a brief review of the available energy sources, CO 2 -emissions and management, and sustainable chemical processing, where energy consumption, CO 2 -emission, as well as economics and environmental impacts are considered. Not all available energy sources have been utilized efficiently, while, the energy source causing the largest emission of CO 2 is being used in the largest amount. The CO 2 management is therefore looking at “curing” the problem rather than “preventing” it. Examples highlighting the synthesis, design and analysis of sustainable chemical processing are presented in the areas of utilization of biomass-based energy-chemicals production, carbon-capture and utilization to produce value added chemicals, and retrofit design of energy intensive chemical processes with significant reduction of energy-consumption are presented. These examples highlight issues of energy-sustainable design, energy-CO 2 neutral design, energy-retrofit design, and energy-process intensification. Finally, some perspectives on the status and future directions of carbon dioxide management are outlined. [ABSTRACT FROM AUTHOR]

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]

Abstract: This paper presents further results of the study on fundamental combustion characteristics of gaseous fuels simulated for a biogas produced through a biomass gasification process with a catalyzer. The main work focuses on combustion characteristics of H2–CO blended fuel and the effect of CO2 dilution on it in a spark-ignition engine under the condition of WOT, MBT and a constant speed of 1500 rpm. Equivalence ratio were limited to lower than 0.8 in order to avoid excessive high combustion temperature to damage the engine, and lean conditions were maintained during the experiment to get acceptable economy and emissions. The results show that the BMEP decreases with an increase in dilution rate. The COV of IMEP is lower than 10% under most conditions, while H2 and CO2 have the opposite influence on brake thermal efficiency. CO2 dilution combustion could induce to remarkable decreasing in NO x emission with little decrease in brake thermal efficiency, which benefits for biomass gaseous fuel application. If 500 ppm of NO x emission and 26% of brake thermal efficiency could be viewed as accepted level, the accepted operation range of H2–CO mixture have been obtained. [Copyright &y& Elsevier]