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The use of alternative diesel fuels has increased due to the demand for renewable energy sources. There is limited knowledge regarding the potential health effects caused by exhaust emissions from biodiesel- and renewable diesel-fueled engines. This study investigates the toxic effects of particulate matter (PM) emissions from a diesel engine powered by conventional petroleum diesel fuel (SD10) and two biodiesel and renewable diesel fuels in vitro. The fuels used were rapeseed methyl ester (RME), soy methyl ester (SME), and Hydrogenated Vegetable Oil (HVO), either pure or as 50% blends with SD10. Additionally, a 5% RME blend was also used. The highest concentration of polycyclic aromatic hydrocarbon emissions and elemental carbon (EC) was found in conventional diesel and the 5% RME blend. HVO PM samples also exhibited a high amount of EC. A dose-dependent genotoxic response was detected with PM from SD10, pure SME, and RME as well as their blends. Reactive oxygen species levels were several times higher in cells exposed to PM from SD10, pure HVO, and especially the 5% RME blend. Apoptotic cell death was observed in cells exposed to PM from SD10, 5% RME blend, the 50% SME blend, and HVO samples. In conclusion, all diesel PM samples, including biodiesel and renewable diesel fuels, exhibited toxicity. [ABSTRACT FROM AUTHOR]

This research compares the air pollution (CO, CO2, HC, NOx, smoke), energy (brake-specific fuel consumption, thermal efficiency) and noise indicators of a compression ignition engine fueled by first-generation biodiesel (rapeseed methyl ester (RME)) and second-generation biodiesel (hydrogenated vegetable oils (HVO)), or conventional (fossil) diesel fuel blends. The concentration of first- and second-generation biodiesel in two-component blends with diesel fuel was up to 15% and 30% (RME15, RME30, HVO15, and HVO30); for comparison, the three-component blend of diesel fuel, HVO and RME (RME15–HVO15) was considered. The fuels' physical and chemical properties were tested in a specialized laboratory, and the engine load conditions were ensured by the engine brake stand. Referring to ship power plants with constant-speed engines, detailed research was carried out in one speed mode (n = 2000 rpm). Studies have shown that two-component fuel blends with HVO are superior to conventional diesel fuel and two-component blends with RME in almost all cases. The HVO in fuel blends reduced fuel consumption up to 1.8%, while the thermal efficiency was close to that of fossil diesel fuel. In addition, a reduction in pollutants was observed: CO by ~12.5–25.0%; HC by ~5.0–12.0%; NOx by ~6.5%; smokiness by ~11–18% (two-component blend) and up to ~29% (three-component blend). The CO2 and noise characteristics were close to those of fossil diesel fuel; however, the trend of reduced smoke emission was clearly seen. A fundamental obstacle to the wide use of HVO can be seen, however, which is the price, which is 25–90% (depending on the EU country) higher than the price of conventional (fossil) diesel fuel. [ABSTRACT FROM AUTHOR]

Biodiesel is one of the promising alternative fuels of the future that is environmentally friendly. Biodiesel can be produced from rapeseed, soybeans, coconut oil, jatropha and many others. It is important to analyze the effect of comparison between diesel fuel and biodiesel to study the effect of combustion and emissions of these fuels. In this research, the simulation of combustion and emission is done with Diesel RK. Three fuels are studied; diesel fuel, rapeseed methyl ester (RME) and soybean methyl ester (SME). The engine was simulated at 2000 rpm and the injection pressures were 944, 1191, 1297, 1420 and 1729 bar respectively. The results show that the specific fuel consumption (SFC), particulate matter (PM), and CO2 emissions of diesel fuel are relatively the same for different injection pressures. However, the SFC, PM and CO2 emissions for rapeseed methyl ester and soybean methyl ester decrease with increasing injection pressure. These results can prove that higher injection pressures in diesel engines can improve combustion and reduce emissions of biodiesel fuel as compared to diesel fuel.

Experimental human exposure studies are an effective tool to study adverse health effects from acute inhalation of particulate matter and other constituents of air pollution. In this randomized and double-blinded crossover study, we investigated the systemic effect on bioactive lipid metabolite levels after controlled biodiesel exhaust exposure of healthy humans and compared it to filtered air at a separate exposure occasion. Eicosanoids and other oxylipins, as well as endocannabinoids and related lipids, were quantified in plasma from 14 healthy volunteers at baseline and at three subsequent time points (2, 6, and 24 h) after 1 h exposure sessions. Protocols based on liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS) methods were developed to detect temporal changes in circulating levels after biodiesel exhaust exposure. The exhaust was generated by a diesel engine fed with an undiluted rapeseed methyl ester fuel. Among the 51 analyzed lipid metabolites, PGF 2α , 9,10-DiHOME, 9-HODE, 5-HETE, 11-HETE, 12-HETE, and DEA displayed significant responsiveness to the biodiesel exhaust exposure as opposed to filtered air. Of these, 9-HODE and 5-HETE at 24 h survived the 10% false discovery rate cutoff (p < 0.003). Hence, the majority of the responsive lipid metabolites were monohydroxy fatty acids. We conclude that it is possible to detect alterations in circulating bioactive lipid metabolites in response to biodiesel exhaust exposure using LC-MS/MS, with emphasis on metabolites with inflammation related properties and implications on cardiovascular health and disease. These observations aid future investigations on air pollution effects, especially with regard to cardiovascular outcomes. [ABSTRACT FROM AUTHOR]

An experimental investigation is performed in a single-cylinder direct-injection (DI) diesel engine using city diesel oil called DI1 and two blends of DI1 with a mixture of glycol ethers. The addition of glycol ethers to fuel DI1 produced oxygenated fuels GLY10 (10.2 mass-% glycol ethers) and GLY30 (31.3 mass-% glycol ethers) with 3% and 9% oxygen content, respectively. The addition of biofuel rapeseed methyl ester (RME) to fuel DI1 produced oxygenated blend RME30 (31.2 mass-% RME) with 3% oxygen content. Engine tests were performed with the four fuels in the DI diesel engine at 2500 RPM and at 20%, 40%, 60%, and 80% of full load. The experimental diesel engine was equipped with devices for recording cylinder pressure, injection pressure, and top dead center (TDC) position and also it was equipped with exhaust gas analyzers for measuring soot, NO, CO, and HC emissions. A MATLAB 2014 code was developed for analyzing recorded cylinder pressure, injection pressure, and TDC position data for all obtained engine cycles and for calculating the main engine performance parameters. The assessment of the experimental results showed that glycol ethers have more beneficial impact on soot and NO emissions compared to RME, whereas RME have less detrimental impact on engine performance parameters compared to glycol ethers.

The quality determination of biofuels requires identifying the chemical and physical parameters. The key physical parameters are rheological, thermal and electrical properties. In our study, we investigated samples of diesel blends with rapeseed methyl esters content in the range from 3 to 100%. In these, we measured basic thermophysical properties, including thermal conductivity and thermal diffusivity, using two different transient methods - the hot-wire method and the dynamic plane source. Every thermophysical parameter was measured 100 times using both methods for all samples. Dynamic viscosity was measured during the heating process under the temperature range 20-80°C. A digital rotational viscometer (Brookfield DV 2T) was used for dynamic viscosity detection. Electrical conductivity was measured using digital conductivity meter (Model 1152) in a temperature range from -5 to 30°C. The highest values of thermal parameters were reached in the diesel sample with the highest biofuel content. The dynamic viscosity of samples increased with higher concentration of bio-component rapeseed methyl esters. The electrical conductivity of blends also increased with rapeseed methyl esters content. [ABSTRACT FROM AUTHOR]

This work presents a comparative ecological assessment of dodecanolethoxylates and rapeseed acid methyl ester ethoxylates as nonionic surfactants. It was found that ethoxylated rapeseed acid methyl esters show higher biodegradability and lower aquatic toxicity compared to 1-dodecanol ethoxylates. A prognostic model for environmental impact of the studied series of surfactants was developed using the data from biodegradation and aquatic toxicity tests combined with estimated concentration of the surfactants in a wastewater stream. It is shown that an ecological risk of bulk application of dodecanolethoxylates can be expected over a longer term, while significant reduction of environmental fate would occur by the alternative use of ethoxylated rapeseed acid methyl esters. We concluded that ethoxylated rapeseed acid methyl esters can be considered as environmentally superior surfactants. [ABSTRACT FROM AUTHOR]

The number of various transport facilities used in Europe is rapidly growing. They release a big amount of pollutants into the atmosphere. Therefore, environment protection from these pollutants ejected by internal combustion engines is a key problem facing us today and which will be acute in the future. Biofuel is the only effective and widely used alternative fuel which can reduce pollution of the environment. The main aim of the present paper is to perform a comparative analysis of burnt gases of engines using rapeseed oil methyl ester and petroleum diesel oil and to determine ecological effectiveness of biofuel used in diesel locomotive engines in railway transport.

This paper presents a comparative analysis of the diesel engine performance and emission characteristics, when operating on diesel fuel and various diesel-biodiesel (B10, B20, B40, B60) blends, at various loads and engine speeds. The experimental tests were performed on a four-stroke, four-cylinder, direct injection, naturally aspirated, 60 kW diesel engine D-243. The in-cylinder pressure data was analysed to determine the ignition delay, the Heat Release Rate (HRR), maximum in-cylinder pressure and maximum pressure gradients. The influence of diesel-biodiesel blends on the Brake Specific Fuel Consumption (bsfc) and exhaust emissions was also investigated. The bench test results showed that when the engine running on blends B60 at full engine load and rated speed, the autoignition delay was 13.5% longer, in comparison with mineral diesel. Maximum cylinder pressure decreased about 1–2% when the amount of Rapeseed Methyl Ester (RME) expanded in the diesel fuel when operating at full load and 1400 min–1 speed. At rated mode, the minimum bsfc increased, when operating on biofuel blends compared to mineral diesel. The maximum brake thermal efficiency sustained at the levels from 0.3% to 6.5% lower in comparison with mineral diesel operating at full (100%) load. When the engine was running at maximum torque mode using diesel – RME fuel blends B10, B20, B40 and B60 the total emissions of nitrogen oxides decreased. At full and moderate load, the emission of carbon monoxide significantly raised as the amount of RME in fuel increased.

The compression ignition and small displacement spark-ignition engines play an important role in the urban air pollution. In particular, vehicles equipped with compression ignition engines are widely used because of their higher performance and fuel efficiency with respect to the spark-ignition ones. Nevertheless, spark-ignition engines with low displacements are even more wide-spreading because of the lower fuel consumption and emissions. They are also used for two-wheeled vehicles, whose easier navigation makes them widely used in heavily congested areas. Their contribution on urban pollution is worsened by the fact that these vehicles have to comply with the Euro 3 standard; light vehicles have, instead, to fulfill the more restrictive Euro 6, which for the compression ignition and gasoline direct injection engines indicates for particle emissions also a number-based regulation. This article aims to characterize the effects of biofuels on engine emissions and performance of compression ignition and spark-ignition engines. The investigation was carried out on different class of engines. Direct injection and a port fuel injection spark-ignition engines fueled with ethanol and its blends, 10 v/v%, 50 v/v% and 85 v/v% of ethanol in gasoline. The compression ignition engine was equipped with a common rail injection system and was fueled with pure rapeseed methyl ester, representative of fatty acid methyl ester, and its blends in diesel, 20 v/v% and 50 v/v%. The gaseous emissions and the particle concentration were measured at the exhaust by means of conventional instruments. Particle size distribution function was measured in the range from 5.6 to 560 nm by means of an engine exhaust particle sizer. A comprehensive characterization of the particulate carbon was performed by means of optical diagnostics in the combustion chamber. In particular, two-dimensional images of flame evolution were detected and processed by two-color pyrometry technique to assess the in-cylinder soot formation and oxidation processes. For both the investigated spark-ignition and compression ignition engines, the use of biofuels shows a partial increase in the specific fuel consumption and a reduction of the soot particles emission. Nevertheless, a further effort on engine technology should be paid to balance the mass with the size and number of the particles. [ABSTRACT FROM AUTHOR]

This paper presents a comparative analysis of the diesel engine performance and emission characteristics, when operating on diesel fuel and various diesel-biodiesel (B10, B20, B40, B60) blends, at various loads and engine speeds. The experimental tests were performed on a four-stroke, four-cylinder, direct injection, naturally aspirated, 60 kW diesel engine D-243. The in-cylinder pressure data was analysed to determine the ignition delay, the Heat Release Rate (HRR), maximum in-cylinder pressure and maximum pressure gradients. The influence of diesel-biodiesel blends on the Brake Specific Fuel Consumption (bsfc) and exhaust emissions was also investigated. The bench test results showed that when the engine running on blends B60 at full engine load and rated speed, the autoignition delay was 13.5% longer, in comparison with mineral diesel. Maximum cylinder pressure decreased about 1–2% when the amount of Rapeseed Methyl Ester (RME) expanded in the diesel fuel when operating at full load and 1400 min–1speed. At rated mode, the minimumbsfcincreased, when operating on biofuel blends compared to mineral diesel. The maximum brake thermal efficiency sustained at the levels from 0.3% to 6.5% lower in comparison with mineral diesel operating at full (100%) load. When the engine was running at maximum torque mode using diesel – RME fuel blends B10, B20, B40 and B60 the total emissions of nitrogen oxides decreased. At full and moderate load, the emission of carbon monoxide significantly raised as the amount of RME in fuel increased. [ABSTRACT FROM AUTHOR]

The non-volatile particle emission characteristics of alternative (rapeseed methyl ester and gas-to-liquid) diesel fuel blends were studied through an experimental investigation carried out on a light-duty common-rail diesel engine. A blend ratio of 10 vol % was chosen as the practical limit for biodiesels in this study, and the research focus was on the particle number concentration and size distribution with various injection strategies, in which the non-volatile emissions were measured using thermodilution. The particle morphology and mass, together with the related gaseous emissions, were measured and analysed. The results indicate that, without any engine modification, adding selected alternative fuels even at a low percentage could result in a favourable reduction in the number of particles and in a significant reduction in the total particle concentration in both the nucleation mode and the accumulation mode. The particle emissions of the three fuels demonstrated monomodal size distributions under most engine conditions tested, except for the engine idling case, which produced a bimodal size distribution. The influence of 10 vol % rapeseed methyl ester or gas-to-liquid diesel blends on the carbon monoxide and nitrogen oxide emissions is not significant. Nevertheless, using these diesel fuel blends may increase the total hydrocarbon emissions and may lead to high particulate matter emissions. [ABSTRACT FROM AUTHOR]

This paper presents the results of theoretical and experimental studies of the combustion of rapeseed methyl ester droplets in comparison with mineral diesel fuel. Droplets of 0.7-1.2 mm diameter were investigated. The effect of the oxidizer equivalence ratio in the range of 1.7-4.0 on the duration of droplet combustion was analyzed using the model of combustion of droplets in an adiabatic shell taking into account Stefan flow. It is shown that the burning time of rapeseed methyl ester droplets is smaller than that of diesel fuel droplets, all other things being equal. [ABSTRACT FROM AUTHOR]

The article presents the results of comparative motor research on FAME biofuels using diesel engine VALMET 320 DMG. Energy (ηe, be) and environmental parameters (CO2, CO, NOx, HC, SM) of the engine were estimated. The obtained data on motor research into new biofuels show that the properties of Camelina sativa biofuels are as good as those observed in standardized rapeseed methyl ester biofuels. In case of using Camelina sativa biofuels blends VME and ZME at different engine loads, exhaust emissions from gas smoke could be reduced up to 10% and 30% accordingly comparing with mineral diesel. When the engine is fueled with tested biofuel blends, carbon monoxide emissions decrease by about 5–6%, and the factor for effective performance increases by approximately 4%. In all range of engine loads, an increase in nitrogen oxide emissions reaching 2–3% was observed. In all cases of using biofuel blends, carbon dioxide emissions keep close to the application of mineral diesel. Santrauka Straipsnyje pateikiami RRME biodegalų palyginamųjų motorinių bandymų, kurie buvo atlikti dyzeliniame variklyje VALMET 320 DMG, rezultatai. Įvertinti variklio energetiniai (ηe, be) ir ekologiniai rodikliai (CO2, CO, NOX, HC, SM). Atliktų naujų biodegalų motoriniai tyrimų rezultatai rodo, kad naujų Camelina sativa biodegalų savybės nenusileidžia standartizuotiems rapso metilesterio biodegalų savybėms. Lyginant su mineraliniu dyzelinu, naudojant Camelina sativa biodegalų mišinius VME ir ZME, skirtingais variklio apkrovos režimais galima sumažinti išmetamųjų dujų dūmingumą atitinkamai iki 10 % ir 30 %. Varikliui dirbant bandomaisiais biodegalų mišiniais, buvo pasiektas 5–6 % anglies monoksido emisijos sumažėjimas ir 4 % naudingo veikimo koeficiento padidėjimas. Visame variklio apkrovos diapazone stebimas 2–3 % azoto oksidų emisijos padidėjimas. Anglies dioksido emisija visais biodegalų naudojimo atvejais išlieka artima mineralinio dyzelino naudojimui. Raktiniai žodžiai: dyzelinis variklis; biodegalai; Camelina sativa; rapso metilesteris

The number of various transport facilities used in Europe is rapidly growing. They release a big amount of pollutants into the atmosphere. Therefore, environment protection from these pollutants ejected by internal combustion engines is a key problem facing us today and which will be acute in the future. Biofuel is the only effective and widely used alternative fuel which can reduce pollution of the environment. The main aim of the present paper is to perform a comparative analysis of burnt gases of engines using rapeseed oil methyl ester and petroleum diesel oil and to determine ecological effectiveness of biofuel used in diesel locomotive engines in railway transport. First published online: 27 Oct 2010

Highlights: [•] RME emitted lower concentration of soot particles than diesel. [•] Increasing the injection pressure reduced the particle size and its concentration. [•] EGR caused smaller particles to agglomerate to form larger size particles. [•] The presence of oxygen in the fuel reduced the exhaust particle number concentration. [Copyright &y& Elsevier]

The term ‘biodiesel’ refers, in this paper, to the fatty acid alkyl esters derived from vegetable, animal or waste oil feedstocks. Numerous economic and environmental drivers, such as the need for fuel security, the requirement to reduce global carbon dioxide emissions and the volatile price of crude oil, are leading to the production of alternative transport fuels such as biodiesel, and their consumption, in increasing quantities. Most published research has focused on the impact of biodiesel on the engine performance and the emissions and, to a lesser degree, on the intention of understanding the impact on after-treatment systems. Where the after-treatment systems have been considered, studies have mainly concentrated on diesel particulate filters and nitrogen oxide reduction systems. To date, no detailed studies in the open literature have addressed the performance of the diesel oxidation catalyst and, subsequently, this work presents the first thorough examination in this area. This study investigated the relative impacts of thermal and chemical factors, when using rapeseed-based biodiesel, on the performance of a diesel oxidation catalyst. The oxidation reaction intensity inside the catalyst brick was examined and used to identify any possible effects caused by different hydrocarbon speciation when using biodiesel compared with that when using baseline diesel fuel. It was found that the carbon monoxide catalyst conversion efficiency over a legislative driving cycle decreased as the biodiesel percentage increased, with conversion reduced by 10% and 16% for 25% biodiesel fuel blend and 50% biodiesel fuel blend respectively compared with baseline diesel. The reduction in the spatial and temporal average catalyst brick temperature between baseline diesel and 50% biodiesel fuel blend over the New European Drive Cycle was found to be up to 15.5 °C. Catalyst light-off curves showed very similar responses when the engine-out emissions of carbon monoxide and hydrocarbons were closely matched to those of baseline diesel fuel. No statistically significant difference between the light-off temperatures of 50% biodiesel fuel blend and baseline diesel was found, indicating that exhaust gas hydrocarbon speciation did not have a significant impact on the catalyst performance. The results show that the exhaust gas temperature and the energy released during the exothermic reactions within the catalyst are the most significant causes of the variations in the catalyst performance when using biodiesel blends. These findings indicate that the increased use of biodiesel could require after-treatment design and control optimisation to negate an adverse impact on the catalyst light-off time and the catalyst performance. [ABSTRACT FROM AUTHOR]

Abstract: Available results about energy and GreenHouse Gases (GHG) balances of biofuels from Life-Cycle Assessment (LCA) or life-cycle based studies present large discrepancies and thus, may lead to contradictory policy-making measures. This work reviewed seven important European LCA studies in a sensitivity analysis approach in order to get a better understanding of the roots of such a debate for three major biofuels in European production: rape methyl ester and ethanol from wheat and sugar beet. Global trends and variability of energy and GHG balances were depicted and completed with a sensitivity analysis carried out for each methodological and data parameter, which allowed making recommendations on the carrying out of LCA in a policy-making or a biofuels comparison context. Methodological choices, and especially allocation rule, appeared as key elements for results variation with influences on balances up to 149%; system expansion approach was identified as the most relevant rule since it integrates the market potential and the environmental interest of by-products promotion, which was pointed out as a crucial point for biofuels sustainability. The influence of local specificity for cultivation data was evaluated up to 167%, which puts too large geographical coverage in question. Modelling uncertainties due to N2O emissions from soils showed influences from 17 to 46%, which represents a crucial challenge for research and for LCA results accuracy. Approximations evaluation pointed out the need to integrate agricultural machinery into the assessment. Finally, land-use issue revealed its dramatic importance for LCA results and the need to define explicit scenarios for land-use alternatives. [Copyright &y& Elsevier]

Abstract: The characteristics of particulate mater size distribution in the exhaust gas of an automotive diesel engine have been studied for a biodiesel blend of 30% rapeseed methyl ester (RME) and 70% ultra low sulphur diesel (ULSD) by volume (B30). The engine, a twin-turbo charged V6 equipped with a common rail fuel injection system, was operated on 16 steady-state points extracted from a corresponding New European Driving Cycle test with no engine system modification and a fast differential mobility spectrometer was used to determine the particulate number concentration and distribution. It is shown that the number-size distribution is dependent on engine operating conditions including the rate of exhaust gas recirculation (EGR). Compared with ULSD, B30 leads to a 41% smaller average size of the particles with EGR but gives rise to a higher number concentration under certain engine operating conditions, with the differences varying between nucleation and accumulation mode. The calculated particle total mass for B30 combustion aerosol is lower than the value with ULSD for all the engine operating conditions tested. The average B30 aerosol was 28% smaller in size on mass basis, compared to ULSD aerosol. For both fuels, the relationship between the particle total number and total mass has been found to be directly correlated and both the number and the mass of particles increase when the mean diameters of particles increase. [Copyright &y& Elsevier]