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This paper describes the needs an challenges in the sector of Life Cycle Assessment of Algae Biofuels

The paper is dedicated to the development of the novel energy saving speed adjustable AC drive with two-stage direct frequency converter (TSDFC) which provides sinusoidal input/output currents and recuperation. Paper describes the two-step control strategy based on the analysis of the TSDFC properties and the problem decomposition. This strategy was realised in the 7.5 kW laboratory setup and first in the world 110 kW experimental-industrial induction motor drive. The results of experimental study are presented.

Although hydrothermal carbonization of biomass components is known to be mainly governed by reaction temperature, consistent reports on the effect and statistical significance of process conditions on hydrochar properties are still lacking. The objective of this research was to determine the importance and significance of reaction temperature, retention time and solid load on the properties of hydrochar produced from an industrial lignocellulosic sludge residue. According to the results, reaction temperature and retention time had a statistically significant effect on hydrochar ash content, solid yield, carbon content, O/C-ratio, energy densification and energy yield as reactor solid load was statistically insignificant for all acquired models within the design range. Although statistically significant, the effect of retention time was 3-7 times lower than that of reaction temperature. Predicted dry ash-free solid yields of attained hydrochar decreased to approximately 40% due to the dissolution of biomass components at higher reaction temperatures, as respective oxygen contents were comparable to subbituminous coal. Significant increases in the carbon contents of hydrochar led to predicted energy densification ratios of 1-1.5 with respective energy yields of 60-100%. Estimated theoretical energy requirements of carbonization were dependent on the literature method used and mainly controlled by reaction temperature and reactor solid load. The attained results enable future prediction of hydrochar properties from this feedstock and help to understand the effect of process conditions on hydrothermal treatment of lignocellulosic biomass.

The ways in which the highly coercive permanent magnet affects the performance of a faceplate magnetic clutch are considered, with constant torque and dimensions.

A design of experiments analysis was performed to investigate the effects of pilot quantity, combustion phasing and exhaust gas recirculation on performance and emissions in a gasoline partially premixed combustion to find out the optimal combination of the all varied parameters. The experimental activities were performed on a light-duty Volvo Euro 6 diesel engine. The test was performed under steady-state operating conditions, nine test points were chosen inside the operating area of the New European Driving Cycle and the Worldwide Harmonized Light vehicles Test Cycles. A fractional factorial analysis in partially premixed combustion on the single and combined effect of the main engine calibration parameters and a global comparison between partially premixed combustion and conventional diesel combustion on the engine performance and emissions adopting the optimal calibration parameters obtained from design of experiments analysis for both combustion modes analysed were presented. The purpose was to obtain the calibration parameters setting that permits to achieve high efficiency and low emissions as well. The partially premixed combustion results show the highest efficiency and lowest NOx emissions adopting a high exhaust gas recirculation rate combined with advanced combustion phasing and lower pilot quantity. Higher efficiency, up to 2.0% units, was obtained in partially premixed combustion with respect to the conventional diesel combustion due to the lower heat transfer loss. Lower soot (about two times) and NOx (about -0.5 g/kWh) levels with partially premixed combustion were obtained and compared to conventional diesel combustion at the same exhaust gas recirculation level. A reduction of about 5% of CO2 and fuel consumption with a 50% of reduction on NOx and soot simultaneously were obtained for partially premixed combustion on the New European Driving Cycle estimation results with respect to the diesel combustion. The information derived from this work are useful to develop and calibrate a light-duty engine that operate in gasoline partially premixed combustion mode achieving NOx close to the Euro 6 limit without adopting any after treatment system.

Life Cycle Assessment is a tool to assess the environmental impacts and resources used throughout a product's life cycle, i.e., from raw material acquisition, via production and use phases, to waste management. The methodological development in LCA has been strong, and LCA is broadly applied in practice. The aim of this paper is to provide a review of recent developments of LCA methods. The focus is on some areas where there has been an intense methodological development during the last years. We also highlight some of the emerging issues. In relation to the Goal and Scope definition we especially discuss the distinction between attributional and consequential LCA. For the Inventory Analysis, this distinction is relevant when discussing system boundaries, data collection, and allocation. Also highlighted are developments concerning databases and Input-Output and hybrid LCA. In the sections on Life Cycle Impact Assessment we discuss the characteristics of the modelling as well as some recent developments for specific impact categories and weighting. In relation to the Interpretation the focus is on uncertainty analysis. Finally, we discuss recent developments in relation to some of the strengths and weaknesses of LCA.

The paper explores, by means of CFD simulations, the potential of the Miller cycle, applied to High Speed Direct Injection (HSDI) Diesel engines, facing the challenge of emissions reduction enforced by the nearterm regulations, with particular reference to Euro VI. In fact, a valuable benefit of the Miller technique is the strong reduction of combustion temperature, thus the abating of NOx emissions, compared to a traditional cycle with the same values of AFR and EGR rate. The practical application of the Miller cycle yields a number of critical issues, which are generally addressed in the paper. However, the goal of the study is to assess the potential and the limits of this technique, more than develop a specific engine configuration. For the analysis, a 2.8 L 4-cylinder turbocharged engine produced by VM Motori was selected, carrying out a comprehensive experimental campaign, at both full and partial load. The experimental data allowed the authors to calibrate two types of numerical models, one for the whole engine analyses (0/1D), the other for the combustion process simulation (CFD-3D). The integrated use of these computational tools provides a reliable comparison between the base engine and the one modified according to the Miller cycle, in terms of both emissions and fuel consumption in the European Driving Cycle. It was found a reduction of NOx and Soot of 25% and 60%, respectively, and a worsening of fuel efficiency of 2%. The abating of NOx can be further enhanced, since it is demonstrated that the engine operated according to the Miller cycle can tolerate higher rates of EGR. (C) 2013 Elsevier Ltd. All rights reserved.