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The current climatic situation requires the implementation of important changes already in the short term: the capture of carbon dioxide and the use of hydrogen are considered among the main solutions. Hydrogen, thanks to the possibility of storing energy, especially from renewable sources, is the basis of the main national and international development plans, while Carbon Capture and Utilization approaches are increasingly at the center of research to optimize the already numerous solutions available and to limit the damage of this pollutant to the environment. The present work, therefore, after an analysis of the current technological solutions for CO2 capture, has focused on the analysis of a cogeneration plant fed by methane in dynamic regime, foreseeing the capture of carbon dioxide from the engine exhaust gases in order to be able to use it later in one of the Power-to-gas solutions: the methanation process with green hydrogen produced through electrolysis and electricity obtained from a photovoltaic field. Using the TRNSYS software, the main components of the system were modeled (eg cogenerator, photovoltaic system, electrolyser) thus allowing an hourly analysis of the hypothesized configuration to be carried out; in particular, for a 20 kWe cogenerator at the service of a small company, the capture of different percentages of CO2 from the exhaust gases and the subsequent reuse in a methanation process with green hydrogen produced by the excess electricity of the photovoltaic field was simulated. The simulations carried out have shown the significant advantage in terms of both CO2 emissions avoided and economic benefits obtained by exploiting the potential of all the cogeneration plant components, while a blind adoption of carbon capture and methanation is difficult to implement due to the too large amount of green solar energy required. This case study shows the need to optimize some of the components needs (e.g. the electricity requests for the electrolysis process) by identifying alternative solutions, such as the use of hydromethane, to cope with the pollution problem.

Il progetto INNOVARE si concentra sull'impiego di tecnologie di conversione di biomasse residuali basate sulla gassificazione e sul successivo impiego del syngas ottenuto in motori termici alternativi funzionanti in assetto cogenerativo. Il presente report è dedicato alla definizione delle condizioni operative ottimali per il processamento di biomasse diverse e al miglioramento delle prestazioni dei motori a combustione interna in alimentazione a syngas. I parametri che maggiormente influenzano la qualità del syngas sono stati riconosciuti con l'obiettivo di definire il loro valore per l'ottenimento di un combustibile da inviare al motore termico caratterizzato dal più elevato potere calorifico possibile. In particolare, si è evidenziato il ruolo fondamentale del rapporto di equivalenza (ER), oltre che della composizione e della dimensione della biomassa trattata.

Il progetto INNOVARE è focalizzato sulla progettazione e realizzazione di innovativi impianti di produzione combinata di energia elettrica, termica e frigorifera di piccola taglia alimentati a biomassa residuale, diffusi sul territorio e basati sull'accoppiamento tra gassificatori a letto fisso e motori a combustione interna (MCI) alternativi. Il progetto intende dimostrare la sostenibilità dell'intera filiera di conversione biomassa-energia in aree con disponibilità di materiali suscettibili di impiego in sistemi di microcogenerazione già individuati, per i quali si propongono azioni migliorative finalizzate all'incremento dell'efficienza energetica e alla riduzione dell'impatto ambientale. Il presente report è dedicato alla caratterizzazione e al miglioramento del componente gassificatore del sistema di micro-cogenerazione individuato, ovvero alla definizione delle condizioni operative ottimali per il processamento di biomasse diverse. I parametri che maggiormente influenzano la qualità del syngas sono stati riconosciuti con l'obiettivo di definire il loro valore per l'ottenimento di un combustibile da inviare al motore termico caratterizzato dal più elevato potere calorifico possibile. In particolare, si è evidenziato il ruolo fondamentale del rapporto di equivalenza (ER), oltre che della composizione e della dimensione della biomassa trattata.

This paper presents results of an experimental investigation on a Diesel car, complying with Euro 5 standard, in two testing environments: in laboratory with car installed on a chassis dynamometer bench and on a track. Car was instrumented with a set of sensors for the assessment of NOx emissions, as well as for the evaluation of interior sound quality. Tests were performed in type-approval driving cycle and steady-state conditions, ranging from 10 to 130 km/h. Vehicle emissive behavior was analyzed in function of ambient conditions and engine parameters. At the same time, acoustic signals coming from pressure measurements acquired inside car cabin in correspondence of passengers' ears, were properly processed in terms of quality of the noise. Some of the most commonly used parameters for sound quality analysis were considered, in order to assess the influence of the different testing environments and the vehicle operating conditions on the acoustic comfort perceived by car's occupants. In the work, air and noise emissions data are jointly analyzed and discussed. The analysis will be preparatory for the development of an overall quality index (encompassing both polluting and noise emissions), which may be useful to evaluate the environmental quality of a vehicle and in aiding policy makers in a variety of urban context.

Asthma is currently defined as a chronic inflammatory disease of the airway. Several evidence indicate that vehicle emissions in cities is correlated with the allergic respiratory diseases. In the present study, we evaluated in the A549 cells the production and release of IL-4, IL-5 and IL-13 after treatment with sub-micron PM(1.0) particles (PM(1.0)), Parietaria officinalis (ALL), and PM(1.0) + ALL together. Our data demonstrated that PM(1.0) + ALL together exhibited the greatest capacity to induce A549 cells to enhance the expression of IL-4 and IL-5 compared with the only PM(1.0) or ALL treatment. Interestingly, IL-13 that is necessary for allergen-induced airway hyper responsiveness, is increased in cells treated with PM(1.0) + ALL together, but is higher expressed when the cells are treated only with the allergen. Our data support the hypothesis that the urban environment damage the acinar lung units and activates cells of the immune system.

Unregulated emissions of polycyclic aromatic hydrocarbons (PAHs), carbonylic compounds, benzene and particulate matter (PM) were quantified in exhausts of a vehicle fleet representative of in-use gasoline cars. Emission factors were obtained during both cold and hot start driving cycles (from urban to motorway driving conditions). Carbonylic compounds were sampled by DNPH cartridges and analyzed by HPLC. Benzene and other light hydrocarbons were collected in bags and then analyzed by GC-FID. PAHs were trapped in XAD-2 cartridges and then analyzed by GC-MS. PM was sampled by using the gravimetric procedure required for diesel cars. The effect of technology is significant with respect to regulated and unregulated emissions but different emissive behavior was found by varying the driving cycles. Cold start has a major influence on hydrocarbon emissions (included unregulated ones). This experimental work was carried out within the framework of the EU Artemis project.

Biodiesel is an alternative and renewable fuel made from plant and animal fat or cooked oil through a transesterification process to produce a short chain ester (generally methyl ester). Biodiesel fuels have been worldwide studied in Diesel engines and they were found to be compatible in blends with Diesel fuel to well operate in modern Common Rail engines. Also throughout the world the diffusion of biofuels is being promoted in order to reduce greenhouse gas emissions and the environmental impact of transport, and to increase security of supply. To meet the current exhaust emission regulations, after-treatment devices are necessary; in particular Diesel Particulate Filters (DPFs) are essential to reduce particulate emissions of Diesel engines. A critical requirement for the implementation of DPF on a modern Biodiesel powered engine is the determination of Break-even Temperature (BET) which is defined as the temperature at which particulate deposition on the filter is balanced by particulate oxidation on the filter. To fit within the exhaust temperature range of the exhaust line and to require a minimum of active regeneration during the engine running, the BET needs to occur at sufficiently low temperatures. In this paper, the results of an experimental campaign on a modern, electronic controlled fuel injection Diesel engine are shown. The engine was fuelled either with petroleum ultralow sulphur fuel or with Biodiesel: BET was evaluated for both fuels. Results show that on average, the BET is lower for biodiesel than for diesel fuel. The final goal was to characterize the regeneration process of the DPF device depending on the adopted fuel, taking into account the different combustion process and the different nature of the particulate matter. Overall the results suggest significant benefits for the use of biodiesel in engines equipped with DPFs.

The main objective of the study was to conduct measurements on powered two-wheelers to improve knowledge about emissive behaviour of this vehicle category on various types of test cycles. The study presents a method to analyse, during different driving cycles on motorcycles, the influence of speed profile on the emission factors, through the basic parameters of elementary kinematic sequences. These sequences were obtained through suitable fragmentation of complex urban driving cycles. The method was applied to evaluate the regulated exhaust emissions (CO, HC, NOX) and to characterize the emissive behaviour of two Euro3 motorcycles (a 250 and a 1000 cm3), tested on a dynamometer bench.

All the experimental investigations performed in the last years on newly sold motorcycles, equipped with a three-way catalyst and electronic mixture control, clearly indicate that CO and HC cold additional emissions, if compared with those exhausted in hot conditions, represent an important proportion of total emissions. Consequently, calculation programs for estimating emissions from road transports for air quality modeling in dedicated local areas should take into consideration this effect. From this motivation, an ...

Mopeds are popular means of transportation, particularly in southern Europe and in eastern and southern Asia. The relative importance of their emissions increases in urban environments which host large fleets of mopeds. In Naples, for example, mopeds make a considerable contribution to HC emissions (about 53%), although the percentage of mopeds (12.4%) in the total circulating fleet is lower than that of other vehicle categories [1]. This study presents a method for analysing the influence of kinematic parameters on the emission factors of mopeds during the ‘‘cold-start’’ and ‘‘hot’’ phases of elementary kinematic sequences (speed-time profiles between two successive stops). These elementary sequences were obtained through appropriate fragmentation of complex urban driving cycles. In a second step, we show how to estimate, for the whole cycle, the duration of the cold phase and the relevant time-dependence function. The method was applied to analyse the regulated exhaust emissions (CO, HC, NOX) of a 4-stroke moped (Euro 2) tested on a dynamometer bench. The experimental data were compared with ARTEMIS and COPERT emission factors, two of the emission models available in Europe to calculate road traffic emissions.

A comparison of the performance of Brassica carinata oil-derived biodiesel with a commercial rapeseed oil-derived biodiesel and petroleum diesel fuel is discussed as regards engine performance and regulated and unregulated exhaust emissions. B. carinata is an oil crop that can be cultivated in coastal areas of central-southern Italy, where it is more difficult to achieve the productivity potentials of Brassica napus (by far the most common rapeseed cultivated in continental Europe). Experimental tests were carried out on a turbocharged direct injection passenger car diesel engine fueled with 100% biodiesel. The unregulated exhaust emissions were characterized by determining the SOOT and soluble organic fraction content in the particulate matter, together with analysis of the content and speciation of polycyclic aromatic hydrocarbons, some of which are potentially carcinogenic, and of carbonyl compounds (aldehydes, ketones) that act as ozone precursors. B. carinata and commercial biodiesel behaved similarly as far as engine performance and regulated and unregulated emissions were concerned. When compared with petroleum diesel fuel, the engine test bench analysis did not show any appreciable variation of output engine torque values, while there was a significant difference in specific fuel consumption data at the lowest loads for the biofuels and petroleum diesel fuel. The biofuels were observed to produce higher levels of NOx concentrations and lower levels of PM with respect to the diesel fuel. The engine heat release analysis conducted shows that there is a potential for increased thermal NOx generation when firing biodiesel with no prior modification to the injection timing. It seems that, for both the biofuels, this behavior is caused by an advanced combustion evolution, which is particularly apparent at the higher loads. When compared with petroleum diesel fuel, biodiesel emissions contain less SOOT, and a greater fraction of the particulate was soluble. The analysis and speciation of the soluble organic fraction of biodiesel particulate suggest that the carcinogenic potential of the biodiesel emissions is probably lower than that of petroleum diesel. Its better adaptivity and productivity in clay and sandy-type soils and in semiarid temperate climate and the fact that the performance of its derived biodiesel is quite similar to commercial biodiesel make B. carinata a promising oil crop that could offer the possibility of exploiting the Mediterranean marginal areas for energetic purposes.

The 1997 Kyoto International Conference Protocol committed industrialized countries to reduce their global emissions of greenhouse gases within the period 2008-2012 by at least 5% with respect to 1990. In view of this and following the European Community directives, the Italian government approved a three-year pilot project to promote the experimental employment of biodiesel. The methyl esters of vegetable oils, known as biodiesel are receiving increasing interest because of their low environmental impact and their potential as an alternative fuel for diesel engines as they would not require any significant modification of existing engines. Consequently, an experimental research program has been developed to evaluate performance and emissions of a Diesel engine fueled with a methyl ester derived from rape seed (Rapeseed Methyl Ester or RME) by changing the composition of the diesel fuel-RME mixture. This program aims to analyze the performance and emissions of a turbocharged D.I. diesel engine fueled with a mixture of RME and diesel fuel. In particular, the experimental investigation has performed a careful analysis of heat release, which has made it possible to give more precise information about the combustion process.