Carbon reduction and cost control of container shipping in response to the European Union Emission Trading System

In response to the EU ETS, we propose a cost model considering carbon emissions for container shipping, calculating fuel consumption, carbon emissions, EUA cost, and total cost of container shipping. We take a container ship operating on a route from the Far East to Northwest Europe as a case study. Environmental and economic impacts of including maritime transport activities in the EU ETS on container shipping are assessed. Results show that carbon emissions from the selected container ship using methanol are the smallest, and total cost of the selected container ship using methanol is the lowest. Among MGO, HFO, LNG, and methanol, methanol is the most environmentally and cost-effective option. Using LNG has greater environmental benefit, while using HFO has greater economic benefit. Compared to MGO, carbon reduction effects of LNG and methanol are 14.2% and 57.1%, and their cost control effects are 7.8% and 26.5%. Compared to HFO, carbon reduction effects of LNG and methanol are 11.7% and 55.8%, and the cost control effect of methanol is 9.3%. Speed reduction is effective in achieving carbon reduction and cost control of container shipping only when the sailing speed of the selected container ship is greater than 8.36 knots. Once the sailing speed is less than this threshold, speed reduction will increase carbon emissions and total cost of container shipping. This model can assess the environmental and economic impacts of including maritime transport activities in the EU ETS on container shipping and explore the measures to achieve carbon reduction and cost control of container shipping in response to the EU ETS.

A comprehensive study on the performance and emission analysis in diesel engine via optimization of novel ternary fuel blends: Diesel, manganese, and diethyl ether

Ecosystem degradation and fossil fuel depletion are the two foremost concerns to look for alternative fuels. Rapid population growth is primarily accountable for higher consumption of fossil fuel sources, although engine technology is achieving milestones in terms of fuel efficiency and lower exhaust emissions in order to contribute towards a sustainable environment. The main root cause of global warming is carbon dioxide emissions; therefore, it is imperative to assess the impact of alternative fuels in diesel engines with an aim to minimize carbon emissions. A current study deals with the reduction of carbon emissions and improvement of efficiency through addition of manganese nano-additive to di-ethyl ether and diesel fuel blend in particulate form. Fuel blends were formed by adding various proportions of manganese to high-speed diesel fuel and stirring the mixture while heating it for 10 min. The blends were then tested in diesel engines at two distinct loads and five engine speed ranges. Emission analyzer was used to ascertain the CO2 output of engine. At higher loads for 10 % diethyl ether in diesel, the increase in brake thermal efficiency was 24.19, 28.17 and 26.86 % when the manganese amount in blend was changed as 250 mg, 375 mg and 500 mg respectively. On the other side CO2 emissions increase by 11.57, 30.52 and 20.33 % for manganese concentrations of 250 mg, 375 mg and 500 mg respectively. Analysis performed with Design Expert 13 showed that the desirability was 0.796 for a blend of 375 mg manganese at 1300 rpm and 4500 W load with 33.0611 % BTE, 334.011kg/kWh BSFC, 67.8821Nm torque, and 6.072 % CO2. Therefore, it can be deduced that manganese nanoparticle blends improved engine performance but CO2 emissions also increase which can be responsible for global warming and it should be reduced through catalytic converters.

Catalytic hydrothermal deoxygenation of sugarcane bagasse for energy dense bio-oil and aqueous fraction acidogenesis for biohydrogen production

The study focuses on the effective conversion of sugarcane bagasse (SCB) by catalytic deoxygenation using various alkali and metal-based catalysts under N₂ pressure employing water as solvent. The specific influence of catalyst over bio-crude yields (bio-oil and aqueous fraction) including energy recovery ratio was explored. The optimum catalytic condition (Ru/C) resulted in ∼ 70% of bio-crude and 28% of bio-oil with an improved HHV (31.6 MJ/kg) having 11.6% of aliphatic/aromatic hydrocarbons (C₁₀-C₂₀) which can be further upgraded to drop-in fuels. The biocrude composed of 44% of aqueous soluble organic fraction (HTL-AF). Further, the carbon-rich HTL-AF was valorized through acidogenic fermentation to yield biohydrogen (Bio-H₂). The maximum bio-H₂ production of 201 mL/g of TOC conversion (K₂CO₃ catalyst) was observed with 7.7 g/L of VFA. The SCB was valorized in a biorefinery design with the production of fuels and chemical intermediates in a circular chemistry approach.

Economic and environmental impact assessments of a new integrated energy system for ocean applications

Transportation via the world's oceans is a critical way to convey goods and fuels between continents that cannot be performed cost-effectively by any other means. However, the big ships heavily rely on fossil fuels, aggravating global emissions. A great resolution to this dilemma is to employ clean fuels to lower carbon emissions. This research paper introduces a new hybrid compound marine engine involving a gas turbine, a solid oxide fuel cell, and a steam Rankine cycle. Three types of analyses, such as exergy, exergoeconomic, and exergoenvironmental analyses, are conducted on this proposed engine. It is found that the engine combination can produce a power of 15.5 MW, which is more than 48% compared to the marine traditional engine power, and the engine performance has up to 61% energy efficiency and 43% exergy efficiency. However, the exergetic efficiency of this engine based on fuel and product principal is 60%, which is more than 17% compared to its exergy efficiency. This engine has a 218 $/h Levelized cost rate and 139 mPt/h environmental rate. Finally, the average overall specific product exergy cost and environment are obtained to be 59 $/GJ and 20 mPt/MJ. By comparing five fuel blends, methane and hydrogen are the most economical and have the least impact on the environment; the second option is ethanol blend and all fuel blends.

Effects of calcium, sodium and potassium on ash fusion temperatures of solid recovered fuels (SRF)

Various types of solid recovered fuels (SRFs) were investigated, then the waste was chemically leached and co-fired with coal and sewage sludge. Ashes with different properties and oxide compositions were used to explain the influence of various ash components (mainly sodium, potassium and calcium) on the Ash Fusion Temperatures (AFTs). Oxide compositions and empirical indices were determined and the effect of these data on the measured AFTs was investigated. An attempt to explain the effects of specific oxides on SRF melting temperatures using FactSage thermodynamic equilibrium software is presented. Thermodynamic equilibrium calculations are also used to predict the onset temperature of the molten phase, the percentage of molten phase at different combustion temperatures, and the possible solid phases that may exist at different temperatures. The mechanism of transformation of the inorganic substance of SRF turned out to be more complex than that of the mineral substance of coal, which resulted from the variable composition of the SRF. The character of temperature changes of the studied wastes after leaching in water and acetic acid in most cases is similar to the courses determined experimentally. For all investigated ashes from obtained the leaching of SRF wastes, the melting temperature decreases with the applied leaching. Potassium and sodium are the key elements causig the formation of low-melting silicates. Depending on the type of waste and leaching agent the lower the value of the B/A and α indices and the CaO content in ash, the lower the shrinkage temperature of the ash.

Elevated emissions of volatile and nonvolatile nanoparticles from heavy-duty diesel engine running on diesel-gas co-fuels

This study experimentally examines the effects of four diesel-gas co-fuels, two engine loads and an aftertreatment on regulated and unregulated emissions from a 6-cylinder natural-aspirated direct-injection heavy-duty diesel engine (HDDE) with an engine dynamometer. Fuel energy of ultra-low-sulfur diesel was substituted with 10% and 20% of gas fuels, including pure H₂, CH₄, and two CH₄-CO₂ blends. The particle number size distributions of volatile and nonvolatile nanoparticles were measured under ambient temperature and after 300 °C heating, respectively. The results show that the gas fuels caused increases of hydrocarbon emission, slight changes of NOx emission, and decreases of opacity. All four gas fuels resulted in elevated emissions of both volatile and nonvolatile nanoparticles at 25% and 75% load, in the range of 29% to 390%. The increased emissions of volatile nanoparticles were variable and without obvious trends. Special attentions should be given to the addition of H₂ under high load, during which significant increases of volatile nanoparticles could be formed not only post-combustion (up to 1376%), but also post-diesel oxidation catalyst plus diesel particulate filter (DOC + DPF). The nonvolatile nanoparticles, on the other hand, could be effectively removed by the retrofitted DOC + DPF, with efficiency >98.2%. A noteworthy fraction of solid particles of sizes <23 nm were found in the exhaust, not being accounted for by current regulatory emission standard.

Energy demand and emissions of a passenger vehicle fueled with CNG, gasohol, hydrous ethanol and wet ethanol based on the key points of the WLTC

A compact sedan vehicle powered by a 1.4 dm³ spark ignition engine fueled with compressed natural gas (CNG), Brazilian gasoline, hydrous ethanol 95% v/v and wet ethanol 88% v/v was evaluated throughout the Worldwide harmonized Light vehicles Test Cycle (WLTC) key points. The vehicle operating points with longest residence time on the WLTC were selected to fuel consumption and emissions evaluation at steady state conditions. The top five key operating points reported in this work accounted for 22% of the total time spent in the entire cycle. The results indicated a significant reduction on greenhouse gases (GHG) emissions and energy demand for operation with CNG. The ethanol-water blends provided reduced emissions of nitrogen oxides (NO_x), but increased specific fuel consumption, carbon monoxide (CO) and GHG emissions in comparison to CNG and gasoline. The operation with gasoline resulted in the minimum CO emissions for all fuels tested, as well as the best fuel consumption between liquid fuels, despite the highest values of carbon dioxide (CO₂), and increased NO_x. Even though ethanol produced little total unburned hydrocarbons (THC), the emissions of alcohols and aldehydes raised an alert for this renewable fuel, whereas CNG emitted the least amount of such pollutants.

Transcription profiles in BEAS-2B cells exposed to organic extracts from particulate emissions produced by a port-fuel injection vehicle, fueled with conventional fossil gasoline and gasoline-ethanol blend

Emissions from road traffic are among the major contributors to air pollution worldwide and represent a serious environmental health risk. Although traffic-related pollution has been most commonly associated with diesel engines, increasing evidence suggests that gasoline engines also produce a considerable amount of potentially hazardous particulate matter (PM). The primary objective of this study was to compare the intrinsic toxic properties of the organic components of PM, generated by a conventional gasoline engine fueled with neat gasoline (E0), or gasoline-ethanol blend (15 % ethanol, v/v, E15). Our results showed that while E15 has produced, compared to gasoline and per kg of fuel, comparable particle mass (μg PM/kg fuel) and slightly more particles by number, the organic extract from the particulate matter produced by E15 contained a larger amount of harmful polycyclic aromatic hydrocarbons (PAHs), as determined by the chemical analysis. To examine the toxicity, we monitored genome-wide gene expression changes in human lung BEAS-2B cells, exposed for 4 h and 24 h to a subtoxic dose of each PM extract. After 4 h exposure, numerous dysregulated genes and processes such as oxidative stress, lipid and steroid metabolism, PPARα signaling and immune response, were found to be common for both extract treatments. On the other hand, 24 h exposure resulted in more distinctive gene expression patterns. Although we identified several common modulated processes indicating the metabolism of PAHs and activation of aryl hydrocarbon receptor (AhR), E15 specifically dysregulated a variety of other genes and pathways related to cancer promotion and progression. Overall, our findings suggest that the ethanol addition to gasoline changed the intrinsic properties of PM emissions and increased the PAH content in PM organic extract, thus contributing to a more extensive toxic response particularly after 24 h exposure in BEAS-2B cells.

Possibility of using alternative fuels in Polish power plants in the context of mercury emissions

The progressive decarbonisation of industry is leading to a reduction in coal consumption and the substitution for coal with other types of fuels, including waste-derived alternative fuels. These fuels are characterised by high variation in the content of highly toxic mercury. Co-combustion with coal can cause significant emissions, exceeding mercury emission limits. Various alternative fuels (refuse-derived fuel (RDF), waste paper, textiles, plastics, film, tires and their char, and sewage sludge) were examined for mercury content. The mercury content in analysed alternative fuels ranged from 0.4 to 92.0 µg Hg/MJ, with an average of 17.7 µg Hg/MJ. The fuels with the highest mercury content were RDFs (2.0-79.3 µg Hg/MJ) and sewage sludge (42.3-92.0 µg Hg/MJ). An acceptable amount of RDF added to hard coal which would remain within the emission limits was estimated to be 9-24% of the chemical energy in the blend. For sewage sludge, this amount was estimated to be 5-13%. For brown coal, with a much higher mercury content than hard coal, co-combustion with alternative fuels has a positive effect on reducing mercury emissions. It is possible to meet the mercury emission limits with a 95% contribution of the chemical energy coming from RDF. The blending of various types of waste supported by mild pyrolysis of high-mercury waste allows alternative fuels with relatively low mercury content to be produced. Such fuels may contribute a reduction in mercury emissions from coal-fired power plants in Poland.

Use of diesel and emulsified diesel in CI engine: A comparative analysis of engine characteristics

Despite a number of efforts to evaluate the utility of water-diesel emulsions (WED) in CI engine to improve its performance and reduce its emissions in search of alternative fuels to combat the higher prices and depleting resources of fossil fuels, no consistent results are available. Additionally, the noise emissions in the case of WED are not thoroughly discussed which motivated this research to analyze the performance and emission characteristics of WED. Brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) were calculated at 1600 rpm within 15%-75% of the load range. Similarly, the contents of NOx, CO, and HC, and level of noise and smoke were measured varying the percentage of water from 2% to 10% gradually for all values of loads. BTE in the case of water emulsified diesel was decreased gradually as the percentage of water increased accompanied by a gradual increase in BSFC. Thus, WED10 showed a maximum 13.08% lower value of BTE while BSFC was increased by 32.28%. However, NOx emissions (21.8%) and smoke (48%) were also reduced significantly in the case of WED10 along with an increase in the emissions of HC and CO and noise. The comparative analysis showed that the emulsified diesel can significantly reduce the emission of NOx and smoke, but it has a negative impact on the performance characteristics and HC, CO, and noise emissions which can be mitigated by trying more fuels variations such as biodiesel and using different water injection methods to decrease dependency on fossil fuels and improve the environmental impacts of CI engines.

Potential and limiting factors in the use of alternative fuels in the European maritime sector

The maritime sector is a key asset for the world economy, but its environmental impact represents a major concern. The sector is primarily supplied with Heavy Fuel Oil, which results in high pollutant emissions. The sector has set targets for deacrbonisation, and alternative fuels have been identified as a short-to medium-term option. The paper addresses the complexity related to the activities of the maritime industry, and discusses the possible contribution of alternative fuels. A sector segmentation is proposed to define the consumption of each sub-segment, so to compare it with the current alternative fuel availability at European level. The paper shows that costs and GHG savings are fundamental enablers for the uptake of alternative fuels, but other aspects are also crucial: technical maturity, safety regulation, expertise needed, etc. The demand for alternative fuels has to be supported by an existing, reliable infrastructure, and this is not yet the case for many solutions (i.e. electricity, hydrogen or methanol). Various options are already available for maritime sector, but the future mix of fuels used will depend on technology improvements, availability, costs and the real potential for GHG emissions reduction.

Characterization, classification and stabilization of industrial wastes for hazard property HP3: Flammable self-heating; assessment and evaluation of 50 industrial wastes

A pilot assessment procedure is introduced and used for the self-heating behavior of 50 industrial wastes based on UN N. 4 test and their subsequent classification as hazardous or non-hazardous, according to the Waste Framework Directive (WFD). When a waste contains self-heating substances it is classified as 'Hazardous Waste' by hazard property HP3: Flammable according to Regulation (EU) No 1357/2014. Self-heating is considered as a precursor stage to spontaneous ignition and fire under certain circumstances, with environmental effects and both human and property losses. The influence of the following parameters on the self-heating nature of the industrials wastes was assessed: temperature, granulometry and moisture. It was demonstrated that although some wastes are classified as absolute non-hazardous (ANH), they may still exhibit self-heating and thus must be classified as hazardous by HP3. It seems that there is a gap between the definition of hazardous waste according to WFD and the entry type of List of Wastes (LoW), regarding the ANH entries. This was found to be the case with two of the wastes examined. Finally, for a waste exhibiting self-heating, experiments were performed with addition of inert material, in order to secure safe management of the waste.

Recent developments on alternative fuels, energy and environment for sustainability

Enhancing energy and environmental systems through sustainable development, in particular integrating concepts of circular economy and cleaner production are important for the emerging needs of humankind. In recent years, the developments in alternative sources of renewable energy counterparts has been prompted to substitute the nonrenewable fossil fuel consumptions towards clearner environment. However, environmental problems arising currently must be carefully addressed and to be solved to conserve the energy, water and other environmental resources for the future. This article highlights the recent developments on alternative energy sources that mainly focus on energy and environmental sustainability, that has been discussed on "The 4th International Conference on Alternative Fuels & Energy (ICAFE-2019)", which was held at Taichung City, Taiwan on October 18-21, 2019. Additionally, it provides useful insights from some of the papers published on a virtual special issue (VSI) of the Bioresourse Technology Journal. The highlighted research works in this review can be used as route-map towards sustainable development and energy efficiency.

Security of supply, strategic storage and Covid19: Which lessons learnt for renewable and recycled carbon fuels, and their future role in decarbonizing transport?

The present work analyses the lessons learnt from the Covid19 (Coronavirus) pandemic that could possibly apply to the energy sector, with a special focus to decarbonizing transport. Distinguishing between short/medium- and medium/long-term options, the scope is to discuss how issues such energy security, energy storage and energy system resilience should deserve more attention. Today, fuel demand has fallen to unprecedented levels, with jet fuel demand being the most affected one. Oil price is at the lowest values recorded for many years while on 20 April it even reached a negative price in the US for the first time in history. While in the short-term low oil prices would be attractive, the long-term negative consequences could be very relevant, with significant associated costs for the EU economy and Member states (MS) related to the collapse of demand and to the socio-economic impacts. New measures should thus be considered in the post Covid19 strategy. In particular, while in a short- to medium-term view the oil sector will require specific support measures to overcome the economic and physical shock brought in by the pandemic, in a medium to long-term perspective domestic sources such as Renewable and Recycled Carbon Fuels (RRCF) should be regarded as a way to secure energy supply, leading to significant technical and economic advantages. Thus, EU should allocate adequate resources in the post-Covid recovery plans to definitely allow the transition to renewable energy sources and particularly to bio-based economy and stainable transport fuels. Decarbonisation of transport through RRCF and economic recovery do not compete, but rather represent a win-win solution in a well-designed and sustainable implementation strategy, especially when low or zero interest-rate investments are foreseen. The EU should take the opportunity to match the UN SDG (Sustainable Development Goals) and EU Green Deal goals with the need to inject economic and financial resources into the real economy improving the socio-economic conditions of EU populations. Both agroforestry and RRCF industry are ready to produce (biomass) or source (waste) the feedstocks as well as the technologies, systems and components needed by the industry along the whole value chain. The roadmap to cleaner transport fuels thus represent an evident opportunity to meet climate, economic and societal post-Covid19 goals, in a win-win-win approach.

The modeling and analysis of transesterification reaction conditions in the selection of optimal biodiesel yield and viscosity

Among alternative fuels, biodiesel has been emphasized as a substantial candidate for diesel engines because of many advantages. However, the main shortcomings preventing more widespread use of biodiesel are high production cost and viscosity. In order to simultaneously overcome both of these shortcomings, the reaction conditions for the transesterification of waste cooking oil (WCO) were optimized using Taguchi and the full factorial design approaches. The analyses of signal to noise ratio and variance were also performed to identify the dominance of reaction conditions on viscosity and biodiesel yield. As a result, the optimal reaction conditions giving the lowest kinematic viscosity (3.991 cSt) and the highest biodiesel yield (98.19%) were determined to be as follows: sodium methoxide amount of 1.00 wt%, reaction time of 60 min, reaction temperature of 55 °C, and methanol to oil molar ratio of 6:1. The catalyst amount and methanol to oil molar ratio were found to be the most significant conditions influencing on the viscosity (10.36% and 78.87% contributions) and the yield (58.48% and 20.17% contributions), respectively. Finally, all physicochemical properties of final waste cooking oil biodiesel (WCOB) produced under optimal reaction conditions were found to meet the EN 14214.

The effect of mineral additives on the process of chlorine bonding during combustion and co-combustion of Solid Recovered Fuels

The use of solid recovered fuels (SRF) is often associated with an increased risk of chloride corrosion because these fuels can be high in chlorine and alkali. One way to reduce the risk of chloride corrosion is the co-combustion of fuel mixtures in the presence of a mineral additive containing chemical compounds that bind the emitted chlorides. This paper concerns the influence of mineral additives - constituting waste material, on the process of the binding of emitted chlorides. One of these waste materials could be a halloysite, not yet used in power industry. The research has shown its high chloride binding effectiveness, comparable to that of kaolin (known in literature as a mineral additive effectively binding chloride). Moreover, the studies have shown that SRF combustion in the presence of stabilized, dried and granulated sewage sludge, with a 25% mass fraction of sewage sludge, allows reducing chloride emissions. Studies are based on tests in a calorimetric bomb.

Electrokinetic nondestructive in-situ technique for rehabilitation of liners damaged by fuels

Underground Storage Tanks (UGST) are often used to store hydrocarbon products and fuels. Liners under such tanks are normally formed to prevent leaching or/and overflow to groundwater. Similar protection is required in case of waste fuels, which are discharged to disposal sites (e.g. ponds, landfill). Thus, a successful protection depends on the liner formation, which might undergo destruction due to leaching. This paper presents the results of experimental investigation to examine the serviceability of liner against leachate infiltration. In order to simulate the behavior of sand-bentonite liners affected by alternative fuels (ethanol and biofuel), the leaching column tests were applied and the hydraulic conductivity was used as an indicator of the effectiveness of the rehabilitation process. Furthermore, the silicate grout solution and pretreatment with surfactant under the effect of electrokinetic phenomena to pre-wash the biofuel residuals in liner were investigated. Silica grout formulations were developed and adequate curing periods were established for electro-silicatization process. Results showed that hydraulic conductivity was reduced fourfold for the case of using three-step electro-rehabilitation for alternative fuels under pressure of 40 kPa, and reduced threefold in the case of 100 kPa pressure on liner.

Control of dioxin emissions from alternative fuels via regulated activated carbon injection and fluegas recirculation

Energy from renewable sources and alternative fuels (AFs) including biomass and refuse or waste derived fuels is spreading worldwide towards resource recovery and sustainability. Hazardous emissions including persisting organic and inorganic pollutants (PPs) such as dioxins/furans and metals are of high concern due to bioaccumnulation and toxic effects. Compliance achieved by excessive overdesign of air pollution control systems (APCS) or process retrofitting with halogen and metal bypass systems, carries along substantial costs. It is shown that (a) traditional injection of activated carbon prior to the APCS based solely on fluegas flowrate may not ensure PP compliance under high precursor varability (e.g., PVC plastic, metals in AFs), while at low precursor rates it leads to excessive activated carbon consumption and PP contaminated flyash, (b) a cost-effective system with feedforward regulated AC injection ensures compliance under high AF precursor variability and averts AC overdosing, (c) An activated carbon injection regulation that guarantees both compliance and reduced emission rates is proposed, (d) Fluegas recirculation offers additional advantages towards more efficient abatement of hazardous PPs, by reducing the overall offgas flowrate and increasing the APCS residence time and removal efficiency. The results may promote efficient reduction of hazardous emissions from AF energy facilities.

Life cycle assessment of the use of alternative fuels in cement kilns: A case study

The benefits of using alternative fuels (AFs) in the cement industry include reduction of the use of non-renewable fossil fuels and lower emissions of greenhouse gases, since fossil fuels are replaced with materials that would otherwise be degraded or incinerated with corresponding emissions and final residues. Furthermore, the use of alternative fuels maximizes the recovery of energy. Seven different scenaria were developed for the production of 1 ton of clinker in a rotary cement kiln. Each of these scenaria includes the use of alternative fuels such as RDF (Refuse derived fuel), TDF (Tire derived fuel) and BS (Biological sludge) or a mixture of them, in partial replacement of conventional fuels such as coal and pet coke. The purpose of this study is to evaluate the environmental impacts of the use of alternative fuels in relation to conventional fuels in the kiln operation. The Life Cycle Assessment (LCA) methodology is used to quantify the potential environmental impacts in each scenario. The interpretation of the results provides the conclusion that the most environmentally friendly prospect is the scenario based on RDF while the less preferable scenario is the scenario based on BS.

Transcriptional response to organic compounds from diverse gasoline and biogasoline fuel emissions in human lung cells

Modern vehicles equipped with Gasoline Direct Injection (GDI) engine have emerged as an important source of particulate emissions potentially harmful to human health. We collected and characterized gasoline exhaust particles (GEPs) produced by neat gasoline fuel (E0) and its blends with 15% ethanol (E15), 25% n-butanol (n-But25) and 25% isobutanol (i-But25). To study the toxic effects of organic compounds extracted from GEPs, we analyzed gene expression profiles in human lung BEAS-2B cells. Despite the lowest GEP mass, n-But25 extract contained the highest concentration of polycyclic aromatic hydrocarbons (PAHs), while i-But25 extract the lowest. Gene expression analysis identified activation of the DNA damage response and other subsequent events (cell cycle arrest, modulation of extracellular matrix, cell adhesion, inhibition of cholesterol biosynthesis) following 4 h exposure to all GEP extracts. The i-But25 extract induced the most distinctive gene expression pattern particularly after 24 h exposure. Whereas E0, E15 and n-But25 extract treatments resulted in persistent stress signaling including DNA damage response, MAPK signaling, oxidative stress, metabolism of PAHs or pro-inflammatory response, i-But25 induced changes related to the metabolism of the cellular nutrients required for cell recovery. Our results indicate that i-But25 extract possessed the weakest genotoxic potency possibly due to the low PAH content.

The fingerprint nature of PCDD in iron ore sinter strand emissions, the effect of suppressants and alternative fuels, and the potential for comparison with the isomer profile of PCDF

It has been previously shown that the isomer profile of PCDF emissions from iron ore sinter plant only varies within limits even when suppressants or alternative fuels are added, to the extent that it can be said to have a 'fingerprint'. The isomer profiles of PCDD from tetra- to hexacholrodibenzo-p-dioxin from the same samples examined for PCDF emissions have been obtained, and show the same tendency for a 'fingerprint ' isomer distribution to occur. Occasional exceptionally high isomer abundances are observed, but these are uncommon. The potential for comparison of the abundances of PCDF and PCDD isomers with similar chlorination patterns to determine whether the same formation process is involved has been examined. It is found that co-elutions prevent extensive comparisons irrespective of whether the SP2331 or DB5ms column is used in the analyses for separation of isomers to provide the results used for comparisons, although they allow limited results to be obtained. It is suggested that analyses using the two chromatography columns to analyse the same sample in parallel could provide more resolution of the isomer profiles for use in comparisons. A pilot study using samples analysed using each column is limited because of detailed differences in the emissions profiles, but demonstrates that greater resolution is possible if the two columns are used to analyse one sample.

Multi-level multi-criteria analysis of alternative fuels for waste collection vehicles in the United States

Historically, the U.S. waste collection fleet was dominated by diesel-fueled waste collection vehicles (WCVs); the growing need for sustainable waste collection has urged decision makers to incorporate economically efficient alternative fuels, while mitigating environmental impacts. The pros and cons of alternative fuels complicate the decisions making process, calling for a comprehensive study that assesses the multiple factors involved. Multi-criteria decision analysis (MCDA) methods allow decision makers to select the best alternatives with respect to selection criteria. In this study, two MCDA methods, Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Simple Additive Weighting (SAW), were used to rank fuel alternatives for the U.S. waste collection industry with respect to a multi-level environmental and financial decision matrix. The environmental criteria consisted of life-cycle emissions, tail-pipe emissions, water footprint (WFP), and power density, while the financial criteria comprised of vehicle cost, fuel price, fuel price stability, and fueling station availability. The overall analysis showed that conventional diesel is still the best option, followed by hydraulic-hybrid WCVs, landfill gas (LFG) sourced natural gas, fossil natural gas, and biodiesel. The elimination of the WFP and power density criteria from the environmental criteria ranked biodiesel 100 (BD100) as an environmentally better alternative compared to other fossil fuels (diesel and natural gas). This result showed that considering the WFP and power density as environmental criteria can make a difference in the decision process. The elimination of the fueling station and fuel price stability criteria from the decision matrix ranked fossil natural gas second after LFG-sourced natural gas. This scenario was found to represent the status quo of the waste collection industry. A sensitivity analysis for the status quo scenario showed the overall ranking of diesel and fossil natural gas to be more sensitive to changing fuel prices as compared to other alternatives.

Environmental levels of PCDD/Fs and metals around a cement plant in Catalonia, Spain, before and after alternative fuel implementation. Assessment of human health risks

The concentrations of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Sn, Tl, V, and Zn, and the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans were determined in samples of soil, vegetation, and air, collected in the vicinity of a cement plant (Catalonia, Spain), before (January 2011 and July 2011) and after (January 2012 and June 2013) alternative fuel partial substitution (fossil fuels by sewage sludge). Seven sampling points were selected at different directions and distances to the facility including two background sampling points. The results were used to assess the health risk assessment for the population living near the facility. Only few significant differences were found before and after alternative fuel partial substitution (Mn in soils and Cd in vegetation). Non-carcinogenic risks were below the safety threshold (HQ<1), while carcinogenic risks were below 10(-5), or exceeding slightly that value, always in the range considered as assumable (10(-6)-10(-4)).