Estimation of Carbon Dioxide Emissions from a Diesel Engine Powered by Lignocellulose Derived Fuel for Better Management of Fuel Production

The depletion of conventional energy sources, including crude oil, is one of the cause of the search for alternative carriers and fuels in order to prevent an energy crisis. Due to the progressing climate change, each new solution must comply with the principles of sustainable development. Dynamic development in the transport sector and, as a consequence, the increase in the number of vehicles on the roads negatively affect the atmosphere and the environment, which is why the share of biofuels, which are used to minimize this negative impact, is steadily increasing. This paper analyzes the emissivity (emission capability) of biofuels such as fatty acid methyl esters (FAME), ethanol, dimethyl ether and butanol and compares them with conventional fuels. A computer simulation was used, based on the real parameters of vehicles and fuels. The test procedure was carried out in accordance with the appropriate New European Driving Cycle (NEDC) approval test for such cars. In addition, a life cycle assessment (LCA) for the fuels and vehicles in question was carried out using the SimaPro package. Based on the results obtained from the z computer simulation, it was found that diesel fuel showed lower emissivity than petrol and its alternatives. However, FAME fuel provided more carbon dioxide than conventional diesel. As far as petrol is concerned, it was less emissive than dimethyl ether. Ethanol and butanol reduced emissions by 7% and 15%, respectively. After taking into account CO2 emissions generated in the production process, both FAME and butanol were not very favorable in the context of other fuels. The results might be used for appropriate fuel use management.

Interest in utilizing advanced lean-burn gasoline and diesel engines has increased in the last decades due to their reduced greenhouse gas emissions and increased fuel economy. One impediment to the increasing use of these engines, however, is the need to develop corresponding catalytic systems for controlling pollutant emissions. In particular, although still far from the fuel neutral United States (US) approach, European (EU) legislation limits for Nitrogen Oxides (NOx) emissions are becoming more and more severe and also type approval procedures are going to radically change with the introduction of Worldwide harmonized Light vehicles Test Cycle (WLTC) and Real Driving Emission (RDE) tests. Considering that test bench and chassis dyno experimental campaigns are costly and require a vast use of resources for the generation of data; therefore, reliable and computationally efficient simulation models are essential in order to identify the most promising technology mix to satisfy emission regulations and fully exploit advantages of diesel and lean-burn gasoline when minimizing the side effect of their emissions. Therefore, the aim of this work is to develop reliable models of the individual aftertreatment components and to calibrate the kinetic parameters based on experimental measurements which can be further used as a virtual test rig to evaluate the effectiveness of each technology in terms of reducing pollutant emissions. In the current work, a brief introduction regarding the passenger car emissions, regulations and control technologies, including in-cylinder control techniques and aftertreatment systems, is provided in Chapter 1. In addition, simulation modelling approaches for aftertreatment applications are discussed. More details about specific aftertreatment components are discussed in the next chapters. As an example, the modeling of a Selective Catalytic Reduction coated on Filter (SCR-F), on the basis of Synthetic Gas Bench (SGB) reactor data is presented in Chapter 2; focusing, in particular, on estimation of ammonia storage capacity, NOx conversion and soot reduction due to passive regeneration. LNT is analyzed in Chapter 3, focusing on the reactor-scale Synthetic Gas Bench (SGB) experiments and calibration of the 1D simulation model for two case studies with the aim to characterize Oxygen Storage Capacity (OSC), NOx Storage and Reduction (NSR) and light-off. The calibrated 1D simulation model is thereafter validated, in Chapter 4, for one of the case studies using engine-out emissions, mass flowrate and temperature traces over Worldwide harmonized Light vehicles Test Cycle (WLTC) as the boundary condition for the inlet of LNT for full-size component. Afterwards, the LNT model calibrated in Chapter 3 is, in Chapter 5, further reduced and linearized with reasonable assumptions to be used as a plant-model with very low computational requirement and in real time applications such as Electronic Control Unit (ECU)/ Hardware-in-the-Loop (HiL) systems. Finally, after discussing NOx control systems in previous chapters, modeling of Diesel Oxidation Catalyst (DOC), which plays a fundamental role not only for the CO and HC conversion, but also for promoting the oxidation of NO into NO2, is discussed in Chapter 6. It is worth noting that depending on the complexity of the kinetic model, different optimization tools are implemented for the calibration; as an example, Brent method is used for calibration of SCR-F kinetic model, likewise, Genetic Algorithm (GA) is used for the calibration of the DOC kinetic parameters; however, for more complex kinetic schemes like LNT both manual and automatic optimization is required to evaluate the most suitable reaction pathways and kinetic parameters. Accordingly, after development of the kinetic model for each aftertreatment component and validation of the full-scale model, further investigations could be devoted to combining the models in order to simulate the whole aftertreatment system and assess the performance over different driving cycles.

Evaluating the environmental impacts of bio-hydrogenated diesel production from palm oil and fatty acid methyl ester through life cycle assessment

From the viewpoint of primary energy diversification and CO2 reduction, interests of using biomass fuel for transportation fuels are rising. Some kinds of FAME (Fatty Acid Methyl Esters), which are obtained from oil fats like vegetable oil using transesterification reaction with methanol, are getting popular for bio-diesel recently. As FAME has unsaturated carbon–carbon bonds which come from feed materials, its performance such as storage stability is concerned. And there are other points of concern, namely, effects of impurities in FAME on car components. In this current situation, technologies to produce high quality fuels from renewable sources, especially from vegetable oils, using petroleum refinery processes should be promising. In our study of the hydrotreatment of palm oil, what we called "Bio hydro-fined diesel (BHD)," it is possible to obtain from vegetable oil hydrocarbons nearly equal to conventional diesel fuel. BHD consists of alkyl chains derived from fatty acids in vegetable oil. BHD has higher oxidation stability than that of FAME. Evaluation of exhaust gases in engine tests on conventional diesel mixed with 10 % BHD showed same THC (total hydrocarbons), CO, and PM (particulate matter) emission as with base diesel alone. LCA (life cycle assessment) evaluation of BHD, petroleum diesel oil, and FAME produced from palm, although Wheel-to-Tank-CO2 of hydrogenated and FAME is higher than that of diesel, Well-to-Wheel-CO2 is lower due to the application of the biomass zero count rule. On the other hand, Well-to-Tank energy efficiency was same as FAME.

Traditional Cambodian food has higher nutrient balances and is environmentally sustainable compared to conventional diets. However, there is a lack of knowledge and evidence on nutrient intake and the environmental greenness of traditional food at different age distributions. The relationship between nutritional intake and environmental impact can be evaluated using carbon dioxide (CO2) emissions from agricultural production based on life cycle assessment (LCA). The objective of this study was to estimate the CO2 equivalent (eq) emissions from the traditional Cambodian diet using LCA, starting at each agricultural production phase. A one-year food consumption scenario with the traditional diet was established. Five breakfast (BF1–5) and seven lunch and dinner (LD1–7) food sets were consumed at the same rate and compared using LCA. The results showed that BF1 and LD2 had the lowest and highest emissions (0.3 Mt CO2 eq/yr and 1.2 Mt CO2 eq/yr, respectively). The food calories, minerals, and vitamins met the recommended dietary allowance. The country’s existing food production system generates CO2 emissions of 9.7 Mt CO2 eq/yr, with the proposed system reducing these by 28.9% to 6.9 Mt CO2 eq/yr. The change in each food item could decrease emissions depending on the type and quantity of the food set, especially meat and milk consumption.

Biodiesels are considered as promising fuels to substitute diesel fuel which can fill the gap of energy shortage while maintaining the diesel engine’s efficiency. Variations in the properties of different biodiesel fuels are caused by the varied fatty acid methyl esters (FAMEs) compositions derived from their parent oils. Therefore, correlating key properties such as cetane number (CN), kinematic viscosity (KV), iodine value (IV) and cold filter plugging point (CFPP) with FAMEs compositions of each biodiesel fuel is significant to developing whatever new types of fuels applied on diesel engines. In this study, an intelligent genetic algorithm (GA)-based back propagation neural network (BPNN) model was proposed to predict the properties of biodiesel fuels according to FAMEs compositions. The hybrid BPNN-GA model has five inputs (methyl palmitate, methyl stearate, methyl oleate, methyl linoleate and methyl linolenate) corresponding to the FAMEs compositions and outputs with estimated fuel properties, with the GA assisting on training to find out local minimum deviation and updated weighting configurations. It was found that the intelligent learning-training method proposed hybrid BPNN-GA model enabled to map the non-linear relationships between the FAMEs compositions and key properties of biodiesel fuels with fairly good agreement. The predicted value of fuel properties agrees with measured ones with R-square up to 96%, along with lower value (less than 10%) over Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE) than those of other empirical correlations. In addition, a sensitivity analysis was conducted to in-depth investigate the FAMEs compositions on key properties. It was concluded that saturated FAMEs have positive impacts on CN, KV and the CFPP, while IV is typically dependent on unsaturated FAMEs. Therefore, it is attainable to formulate new types of alternative fuels based on the required properties on diesel engine applications.

Fishing vessel operation highly depends on fossil fuels such as gasoline, diesel to generate power. Combustion of fossil fuel would generate greenhouse gas emission such as carbon dioxide. However, the estimation of carbon dioxide emission from fishing vessel is rather scarce in Malaysia. This paper describes carbon dioxide emission estimation from fishing vessels operation in Selangor. This study was conducted at four fisheries districts in Selangor where fishing vessels anchored for operation. Fishing operation activities were divided into four fisheries operation zones (A, B, C, and C2). It involved 3,252 fishing vessels. Firstly, carbon dioxide emission for each vessel is determined by using tier 1 method waterborne navigation equation provided from Chapter 3 mobile combustion, volume two Energy, 2006 IPCC Guidelines for National Greenhouse Gas Emission Inventory. After the carbon dioxide emission estimation was calculated, an inventory of emission was carried out. Then, ANOVA test was used to determine the significant differences between fishing gear and fisheries zones. Total carbon dioxide emission from fishing vessels operation in Selangor is 295.44 Gg CO2 for 2012. ANOVA test indicated there is difference in the mean carbon dioxide emission estimation between different types of fishing gear. There are also significant differences in the mean carbon dioxide emission estimation from four different fisheries zones in Selangor. Turkey Kramer Multiple Comparisons was applied to determine the pair of carbon dioxide emission of fishing vessels between types of fishing gears and fisheries zones. The burning of 89.35 Gg of fossil fuel by fishing operation released 295.4 Gg in 2012. Total amount of carbon dioxide emission from fishing vessel is low compare to latest Malaysia total carbon dioxide emission in 2000, 222,990 Gg CO2. In conclusion, status of carbon dioxide emission by fishing vessel operation has been determined for Selangor.KeywordsCarbon dioxide emissionFuel consumptionFishing vessel operation

Life cycle greenhouse gas emissions impacts of the adoption of the EU Directive on biofuels in Spain. Effect of the import of raw materials and land use changes

<div class="section abstract"><div class="htmlview paragraph">The increasingly stringent emission legislation worldwide and the demand for independence from fossil energy carriers represent major challenges for the future development of diesel engines, particularly for maintaining the diesel engine’s positive characteristics, such as its dynamic driving performance and fuel economy, while drastically reducing emissions. This survey investigates alternative fuel blends used in a state-of-the-art EURO 6 diesel engine with different shares of biomass to liquid, hydrotreated vegetable oils and fatty acid methyl ester, which present a possibility to meet these requirements. In particular, the reduction of particulate matter and, as a result, the possibility to reduce nitrogen oxides emissions holds remarkable potential for the application of synthetic fuels in diesel engines. The investigated fuel blends generally demonstrate good applicability when used in the test engine with standard settings. Adaptions to engine parameters (e.g., injection timing or exhaust gas recirculation) hold further potential. With respect to the EU’s targeted 10% bio-quota by 2020 two ternary fuel blends containing conventional diesel fuel, fatty acid methyl ester and biomass to liquid or hydrotreated vegetable oils were also tested and featured excellent performance in terms of emissions and efficiency.</div></div>

Performance and exhaust emissions of diesel engines using microalgae FAME and the prospects for microalgae HTL biocrude

One of the major risks mankind has encountered during recent years is, without a doubt, the anthropogenic contribution to environmental pollution [...]

<div class="section abstract"><div class="htmlview paragraph">A modern diesel engine is a reliable and efficient mean of producing power. A way to reduce harmful exhaust and greenhouse gas (GHG) emissions and secure the sources of energy is to develop technology for an efficient diesel engine operation independent of fossil fuels. Renewable diesel fuels are compatible with diesel engines without any major modifications. Rapeseed oil methyl esters (RME) and other fatty acid methyl esters (FAME) are commonly used in low level blends with diesel. Lately, hydrotreated vegetable oil (HVO) produced from vegetable oil and waste fat has found its way into the automotive market, being approved for use in diesel engines by several leading vehicle manufacturers, either in its pure form or in a mixture with the fossil diesel to improve the overall environmental footprint. There is a lack of data on how renewable fuels change the semi-volatile organic fraction of exhaust emissions. In order to characterize and explain the difference in exhaust emissions from fossil diesel, HVO and RME fuels, particulate matter (PM) emissions were sampled at two exhaust positions of an experimental single cylinder Scania D13 heavy-duty (HD) diesel engine: at the exhaust manifold, and after a diesel oxidation catalyst (DOC). Advanced analyzing techniques were used to characterize the composition of the organic PM. Special attention was paid to an operating point at 18% intake oxygen level with constant engine operating conditions where the emission level of nitrogen oxides (NOx) was low, and carbon monoxide (CO) and total hydrocarbon (THC) were relatively low. On-line aerosol mass spectrometry (AMS) suggests that the chemical composition of the organic aerosols (OAs) was similar for HVO and diesel. However, RME both reduced the OA emissions and changed the composition with evidence for fuel signatures in the mass spectra. When the emissions were aged in an oxidation flow reactor to simulate secondary organic aerosol (SOA) formation in the atmosphere, it was found that OA concentration strongly increased for all fuels. However, SOA formation was substantially lower for RME compared to the other fuels. The DOC strongly reduced primary organic emissions in both the gas (THC) and particle phase (OA) and only marginally affected OA composition. The DOC was also effective in reducing secondary organic aerosol formation upon atmospheric aging.</div></div>

Environmental and energy assessment of alternative fuels for diesel in Thailand

Fuel property evaluation of unique fatty acid methyl esters containing β-hydroxy esters from engineered microorganisms

The body of life cycle assessment (LCA) literature is vast and has grown over the last decade at a dauntingly rapid rate. Many LCAs have been published on the same or very similar technologies or products, in some cases leading to hundreds of publications. One result is the impression among decision makers that LCAs are inconclusive, owing to perceived and real variability in published estimates of life cycle impacts. Despite the extensive available literature and policy need formore conclusive assessments, only modest attempts have been made to synthesize previous research. A significant challenge to doing so are differences in characteristics of the considered technologies and inconsistencies in methodological choices (e.g., system boundaries, coproduct allocation, and impact assessment methods) among the studies that hamper easy comparisons and related decision support. An emerging trend is meta-analysis of a set of results from LCAs, which has the potential to clarify the impacts of a particular technology, process, product, or material and produce more robust and policy-relevant results. Meta-analysis in this context is defined here as an analysis of a set of published LCA results to estimate a single or multiple impacts for a single technology or a technology category, either in a statisticalmore » sense (e.g., following the practice in the biomedical sciences) or by quantitative adjustment of the underlying studies to make them more methodologically consistent. One example of the latter approach was published in Science by Farrell and colleagues (2006) clarifying the net energy and greenhouse gas (GHG) emissions of ethanol, in which adjustments included the addition of coproduct credit, the addition and subtraction of processes within the system boundary, and a reconciliation of differences in the definition of net energy metrics. Such adjustments therefore provide an even playing field on which all studies can be considered and at the same time specify the conditions of the playing field itself. Understanding the conditions under which a meta-analysis was conducted is important for proper interpretation of both the magnitude and variability in results. This special supplemental issue of the Journal of Industrial Ecology includes 12 high-quality metaanalyses and critical reviews of LCAs that advance understanding of the life cycle environmental impacts of different technologies, processes, products, and materials. Also published are three contributions on methodology and related discussions of the role of meta-analysis in LCA. The goal of this special supplemental issue is to contribute to the state of the science in LCA beyond the core practice of producing independent studies on specific products or technologies by highlighting the ability of meta-analysis of LCAs to advance understanding in areas of extensive existing literature. The inspiration for the issue came from a series of meta-analyses of life cycle GHG emissions from electricity generation technologies based on research from the LCA Harmonization Project of the National Renewable Energy Laboratory (NREL), a laboratory of the U.S. Department of Energy, which also provided financial support for this special supplemental issue. (See the editorial from this special supplemental issue [Lifset 2012], which introduces this supplemental issue and discusses the origins, funding, peer review, and other aspects.) The first article on reporting considerations for meta-analyses/critical reviews for LCA is from Heath and Mann (2012), who describe the methods used and experience gained in NREL's LCA Harmonization Project, which produced six of the studies in this special supplemental issue. Their harmonization approach adapts key features of systematic review to identify and screen published LCAs followed by a meta-analytical procedure to adjust published estimates to ones based on a consistent set of methods and assumptions to allow interstudy comparisons and conclusions to be made. In a second study on methods, Zumsteg and colleagues (2012) propose a checklist for a standardized technique to assist in conducting and reporting systematic reviews of LCAs, including meta-analysis, that is based on a framework used in evidence-based medicine. Widespread use of such a checklist would facilitate planning successful reviews, improve the ability to identify systematic reviews in literature searches, ease the ability to update content in future reviews, and allow more transparency of methods to ease peer review and more appropriately generalize findings. Finally, Zamagni and colleagues (2012) propose an approach, inspired by a meta-analysis, for categorizing main methodological topics, reconciling diverging methodological developments, and identifying future research directions in LCA. Their procedure involves the carrying out of a literature review on articles selected according to predefined criteria.« less