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Cellulose, the most abundant terrestrial biopolymer, has immense potential for a range of applications, such as textiles, biomedical applications, and sustainable building components. Due to the recalcitrant nature of lignocellulosic materials, various alkaline and acid pretreatment methods have been developed to recover mono sugars for fermentation. Simultaneous production of bioethanol and nanocrystalline cellulose (NCC) from pretreated Formosan alder biomass was conducted in two stages. Formosan alder biomass was treated using unbleached kraft (UEK), acid steam explosion (SEP), and bleached acid steam explosion (BSEP) and hydrolyzed using cellulase. Filter paper (FP) and alpha-cellulose were used as positive controls. Bioethanol fermentation using E. coli Ko11 was conducted. Residual biomass was further recovered to produce NCC. After 96 h enzyme hydrolysis, the highest sugar yields were 383.4 and 329.84 mg glucose/g biomass for the FP and UEK samples. The highest bioethanol fermentation yields were 4.18 and 3.62 g bioethanol/g biomass for FP and UEK samples. During enzyme hydrolysis of the biomass, crystallinity increased. NCC yields were 613.93 nm (68%) and 1583 nm (73%) for the FP and UEK samples. The negative impact of lignin content was reflected in the particle length of the final NCC. Further lignin removal is required for optimal NCC production. This study showed that Formosan alder biomass could be used to produce both bioethanol and NCC. • This study integrates sustainable energy with advanced nanomaterial processing. • Prove that a native species is able to fulfill the future need. • Feedstock crystallinity is a key factor impacting acid hydrolysis efficiencies. • Degree of delignification process is dictating final bioethanol yields. • Nanocrystalline cellulose yields were 73% for unbleached kraft pulp as the feedstock. [ABSTRACT FROM AUTHOR]

Hydrous ethanol is a green fuel with great potential to deal with crises in the environment and energy. The study on the ethanol life cycle showed hydrous ethanol with 10%–20% water content had the best benefit, but the water content >10% would deteriorate engine power and emission performance. In this paper, the effects of the 30 vol% laboratory-grade H 2 O 2 on the combustion performance and emission characteristics were explored in an ethanol/gasoline combined injection engine. At the engine operating condition of engine speed/manifold air pressure = 1500 rpm/49.5 kPa, the H 2 O 2 -ethanol blend direct injection (DI) and gasoline port injection were conducted. Results showed that H 2 O 2 greatly improved the operating performance of the hydrous ethanol/gasoline engine. As the 30 vol%-H 2 O 2 ratio in the H 2 O 2 -ethanol blend (H 2 O 2 r) increased, the P max and the T max first increased and then decreased. Both CA0-10 and CA10-90 were slightly extended. For the DI ratio = 10%–40%, the optimal IMEP was obtained at H 2 O 2 r = 15%, which was 0.09 bar–0.11 bar higher than H 2 O 2 r = 0%. The optimal BTE was 0.86%, 0.75%, 0.71% and 0.75% higher than H 2 O 2 r = 0%, respectively. As the H 2 O 2 r and DI ratio increased, HC and NO x emissions descended, and CO emissions decreased first and then ascended slightly with the critical H 2 O 2 r = 10%–15%. Optimal CO, HC and NO x emissions were 21.76%, 58.83% and 42.02% lower than gasoline, respectively. H 2 O 2 could reduce particulate emissions, while the H 2 O 2 r < 15% at the DI ratio = 30%–40% should be adopted. • Effects of various H 2 O 2 -ethanol blend ratios were studied in a SI engine. • H 2 O 2 can decrease the CA10-90 of a hydrous ethanol/gasoline engine. • H 2 O 2 can propel the power and economic performance of the hydrous ethanol/gasoline engine. • H 2 O 2 can simultaneously reduce gaseous emissions and particulate matter. • H 2 O 2 is a promising additive to enhance the engine operating performance. [ABSTRACT FROM AUTHOR]

The global production and consumption of ethanol are expected to increase. The growing interdependence of markets and nations, producers and consumers of biofuels, has led actors to seek and devise mechanisms intended to develop the sector. This paper aims to analyze the interdependent international relations between Brazil and other ethanol biofuel producer and consumer countries. To do so, the paper explores the Theory of Complex Interdependence and the Game Theory. A quali-quantitative study was conducted involving the application of two questionnaires to experts on biofuels and documentary analysis aided by QDA Miner ® software. The results show that Brazil shares highly interdependent relations with The United States, an intermediate degree of interdependence with Europe and a low degree of interdependence with China. The dimensions of those interdependent relations can be ranked, according to importance, in the following order: first the political, then the economic, technical and finally the social–environmental dimensions. A number of actions can be envisaged that could lead ethanol to achieve an increasingly strategic position in the diversification of the energy matrix in different countries: technological efforts to improve production efficiency; the creation of globally-integrated policies designed to provide security and develop the production and consumption infrastructure; the reduction of international tariffs on the product; and the transformation of ethanol into a global commodity with a large number of countries buying and selling the product. This paper faced the challenge of integrating approaches and concepts from two complex theoretical areas: Complex Interdependence Theory and Game Theory. The research methodology and the insights gained from the ethanol case contribute to the literature on the applicability of these two theoretical approaches. [ABSTRACT FROM AUTHOR]

This paper describes the impact pathway approach for estimating an economic value of pollution effects of acetaldehyde (CH 3 CHO) associated with bioethanol vehicle transport in Oslo as a climate policy. The approach rests on results obtained in an innovative measurement campaign and by means of air pollution dispersion-models, followed by an impact assessment and economic valuation of the potential externalities. This makes a state-of-the-art methodological technique to reach greater knowledge on the economic costs of urban air quality impacts resulting as a side effect of climate change policy. The social economic costs estimated in this paper are then compared to likely social economic benefits (i.e. avoided social economic damage cost) of reduced nitrogen dioxide (NO 2 ) and carbon dioxide-(CO 2 ) emissions. The carcinogenic risk from long-term inhalation exposure to acetaldehyde emissions, leads in this paper to a moderate cost estimate associated with the combustion of bioethanol in vehicles in Oslo. Productivity and welfare loss is the dominant cost component, whereas the direct medical costs constitutes only a small part of the total social economic costs. The costs however, expect to be significantly lower than the combined economic benefits from reduced emissions of target compounds, such as carbon dioxide and nitrogen dioxide. [ABSTRACT FROM AUTHOR]

The ever growing concerns about the impact of first generation bioethanol on food chain and on biodiversity have shifted the focus of research to second generation (2G) bioethanol technologies. The 2G-bioethanol's production relies on biomass feedstock that could provide a more sustainable energy generation without compromising food security and environment. Indeed, this production process exploits non-food crops, food crops residues, wastes of wood-based or food-based industries such as wood chips, skins or pulps from fruit pressing, respectively. Nevertheless, the industrial process of 2G-bioethanol's production is still in its infancy, indeed the future and the sustainability of the 2G-bioethanol strongly depend upon the development of the current technology. In this paper particular attention will be paid to the role of thermophilic microorganisms and their enzymes to the biotechnology's development of the bioethanol's production process. [ABSTRACT FROM AUTHOR]

Abstract Current narrative on biofuels is backed up by a large number of studies published in the scientific literature that address second-generation bioethanol only through a single topic approach, nonetheless in the vast majority of cases transition to this energy carrier is evaluated as a generally 'promising' technology. This paper presents a first attempt in proposing an integrated evaluation of the actual benefits expected from bioethanol in the transport sector, by applying the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) to the prospective realization of a local system of bio-refinery in Campania Region (Southern Italy). MuSIASEM is a multi-criteria analysis enabling to deal with the complexity of a territorial energy system. Since the unavoidable intrinsic uncertainty, the study does not focus on predictions, but adopts a strategy of Quantitative Story-Telling about some relevant results underlying the limits and critical issues about the energy converter fabric, the economic profitability, environmental constraints and the questionable concept of marginal land. The findings suggest concluding toward falsification of key points in the current narrative: (i) the system is not an efficient solar energy converter; (ii) it fails to realize many of the expectations for a renewable energy carrier producer; (iii) the contribution to decarbonization strategies is not as high as desired and other environmental impacts could not be neglected; (iv) the very large land requirement is hardly compatible with conversion of truly marginal land in Campania region; (v) compared to alternate land uses it does not seem an actually promising strategy to regain value from rural economy. Graphical abstract Image 1 Highlights • Single topic studies are not useful for comprehension of a territorial biorefinery. • Multi-scale and multi-dimensional approach to face the ambiguity of energy concept. • Performance's comparison of two distinct energy production systems is misleading. • Decarbonization and marginal lands concepts are a simplification of the problem. [ABSTRACT FROM AUTHOR]

Abstract In the context of China's severe energy and environmental problems, as an alternative vehicle fuel bioethanol is a promising choice because its theoretically renewable and carbon neutral. To guarantee grain security, China is developing non-grain fuel ethanol. Based on a life cycle assessment (LCA), this paper assesses the uncertainty of energy efficiency and environmental performance in the development of cassava ethanol of 1.5-generation bioethanol whose raw materials are non-staple crops. The results show that cassava ethanol is a good alternative vehicle fuel from the view of energy efficiency. From an environment perspective, global warming potential and photochemical ozone formation potential of cassava ethanol are better than gasoline, but acidification potential and respiratory inorganics inferior. The Monte Carlo simulation reveals cassava ethanol is feasible compared with gasoline in the case of uncertain variables. Among these uncertain variables, cassava yield, nitrogen fertilizer use, and steam use are the most important variables for energy efficiency and environmental performance of cassava ethanol. Furthermore, this study calculates the potentials for energy savings and emissions reduction with improving key aspects, and gives the suggestions of enhancing the performance of key indicators to promote the development of bioethanol vehicle fuel. Highlights • Cassava ethanol is a good alternative vehicle fuel from the view of energy efficiency. • Cassava ethanol decreases GWP and POFP, but increases AP and RI compared with gasoline. • Cassava yield, nitrogen fertilizer usage and steam usage have the greatest impact on cassava ethanol. • The potentials of energy-saving and emission-reduction are calculated with improving key aspects. [ABSTRACT FROM AUTHOR]

Currently, car ownership in China accounts for 20% of the world's cars, and there is tremendous growth potential in China's motor vehicle market, along with the quick improvement of the urbanization level. These advances will gradually increase the energy and environmental pressures faced by China. A direct and effective method to address these issues is to develop alternative vehicle fuels. This paper elaborates on the necessity and feasibility of developing fuel ethanol in China by comparing fuel ethanol with five kinds of alternative fuels that have either been put into use or are in the demonstration stage. Additionally, we construct a triple-perspective (raw material resource-vehicle-infrastructure) analysis framework. Based on this framework, the review concludes that China should develop 1.5-generation bioethanol in accordance with its own conditions in view of raw material resources. Compared with gasoline, bioethanol has the advantages of having an antiknock ability, engine efficiency and torque output from the perspective of the vehicle, but it also has some performance disadvantages. For infrastructure, the policies regarding using marginal land for planting energy crops lack specific and definite goals. Therefore, the government should increase its investment and develop new varieties of 1.5-generation bioethanol with higher quality and yield; step up efforts to help consumers understand that ethanol is a safer and more friendly antiknock additive than methyl tertiary butyl ethers (MTBE), which should be limited in its additive amount; and assess the environmental and economic feasibility of marginal land used for energy crops. [ABSTRACT FROM AUTHOR]

This paper proposes a multi-objective robust possibilistic programming model for the design of a sustainable switchgrass-based bioethanol supply chain network under the epistemic uncertainty of input data considering conflicting economic, environmental and social objectives. The newest and most effective environmental and social life cycle assessment-based methods are applied to the proposed model to measure the relevant environmental and social impacts. To deal with uncertain parameters effectively, a novel multi-objective robust possibilistic programming approach is developed which is able to maximize the mean value of supply chain performance and control the optimality as well as feasibility robustness. Computational analysis is also provided by using a real case study in Iran to show the performance and validity of the proposed model. The results show that with an increase of 2.43% in the economic objective function, a desirable level of environmental and social protection is achieved. Additionally, the mean value of supply chain performance will enjoy more desirable values if the influence of optimality robustness and feasibility robustness decreases. The results also demonstrate that the proposed robust model outperforms the deterministic model in terms of the average and standard deviation measures. [ABSTRACT FROM AUTHOR]

The article reassesses a recent case study on six bioethanol production processes in China, to develop a methodology that discriminates the most energy-efficient process. The original research explored the joint method of Life Cycle Assessment and Data Envelopment Analysis (LCA + DEA). However, DEA is sensitive to problems with a disproportionate number of variables to alternatives and LCA usually requires analysis with several inputs and outputs. The original research indicated two sources as being tied for energy efficiency, which is not relevant to decision-makers aiming to invest in the most efficient process. The method proposed here uses a combinatorial and probabilistic approach to improve discrimination and create scenarios for the reduction of inputs and the increase of outputs, even for efficient processes. Results show that the proposed method has better discriminatory power than the referenced paper. [ABSTRACT FROM AUTHOR]

Polyethylene (PE) and polypropylene (PP) can be synthesized from biomass through dehydration, dimerization, and metathesis reactions from ethanol or methanol-to-olefin reaction of synthesis gas. This paper examines the socioeconomic aspects of such biomass-derived resin production, which are composed of environmental impacts quantified by life cycle analysis (LCA) and the structure of generated value flows specified by structural path analysis (SPA) based on a Japanese input–output table. Missing inventory data were estimated by process simulation using Aspen Plus™ and Aspen HYSYS™ with design information extracted from the literature, patents, and design heuristics. LCA based on actual and demonstration plants with process simulation shows the environmental advantage of biomass-derived resins on greenhouse gas (GHG) emissions reduction. PE production has the largest effect on GHG emissions reduction, followed by bioethanol from a gasoline mixture, and PP. The uncertainties in agricultural processes also influence the potential application of international and domestic bioethanol production and synthesis gas obtained from the gasification of waste woods. According to SPA results for gasoline, PE, PP, and plastic products, the cyclicality of resins and plastic products, which was quantitatively analyzed as the total cyclic cash flows from target products to final demands, is much larger than that of gasoline. Based on these results, biomass-derived resin production has the potential to increase added values in an economy, with a corresponding decrease in GHG emissions. [ABSTRACT FROM AUTHOR]

This paper describes the results of a life cycle assessment of sweet sorghum stalk (SSS)-based ethanol in North China. We determined the environmental performance of SSS-based ethanol and examined its advantages and disadvantages, as compared to gasoline, focusing on the life cycle of feedstock production, transportation, ethanol production and distribution, and use. The GREET transportation model and the method developed by the Centre of Environmental Sciences at Leiden University (CML method) were used to compile a life cycle inventory and to assess environmental impacts. Results indicate that SSS-based ethanol has advantages in terms of energy consumption, with a well to wheel decrease of 85% fossil energy and 44% global warming potential, as compared with gasoline. Abiotic depletion potential, acidification potential, and photochemical ozone creation potential were also 50–90% lower than in the case of gasoline, while human health toxic potential was 36% lower. However, SSS-based sorghum did not have advantages over gasoline in terms of life cycle cost, land use, and water consumption. Results indicate that such an evaluation cannot just consider a few types of environmental impacts, researchers should promote systematic and comprehensive life cycle assessment of ethanol to guide the development of an energy strategy for China. [ABSTRACT FROM AUTHOR]

China's growing capacity of bioethanol production renders the conversion of ethanol-to-jet fuel (ETJ) promising. However, ETJ studies are currently scarce in China. This study employed process simulation to model two novel ETJ processes that combined corn cob gasification, syngas-to-ethanol, and ethanol-to-jet fuel. This paper also discussed the other three ETJs, in which ethanol were obtained via direct-fermentation of corn, cassava, and corn cob, respectively. Life cycle assessment (LCA) was performed to evaluate energy consumption and greenhouse gas (GHG) emissions of ETJs in China. The results showed that the ETJ pathway, which included corn cob gasification plus fermentation, showed the least energy consumption and GHG emission, with 370.05 KJ/MJ jet fuel and 31.66 gCO 2 eq/MJ jet fuel, respectively. Sensitivity analysis was performed to identify parameters that had a significant impact on the results, and uncertainty analysis was implemented to check the reliability of the result. Further analysis revealed that cleaner electricity and heat production could effectively reduce the GHG emissions of the energy-intensive ETJs, with the highest reduction of 21.55%. Given that few life cycle assessments of ETJs in China have reported, this study can assist policy-makers to decide the path in which China's sustainable aviation fuel (SAF) should evolve. [Display omitted] • Life cycle analysis for 5 ethanol-to-jet fuels established toward China situation. • The process based on corn-cob-syngas fermentation showed the best carbon reduction. • Optimizing biomass and ethanol conversion could greatly reduce GHG emissions. • Electricity mixes highly impacted on the process based on corn-cob-syngas catalysis. • Life cycle results were mostly sensitive to the displacement allocation method. [ABSTRACT FROM AUTHOR]

Although there have been international frameworks for limiting global warming, however, sustainable actions are not on the same track in terms of speed and scale due to the lack of an explicit pathway. A large strand of the literature has examined the emissions-mitigating effect of R&D expenditure and biofuel energy consumption but in a linear framework and disregarded the factors that cause non-linearity. In that respect, this study aims to offer a new perspective on the asymmetric response of greenhouse gas emissions to government energy R&D expenditure and biofuel use in the United States over the 1981–2020 period using a nonlinear time series approach. The results confirm the asymmetrical relationships between government energy R&D, biofuel use, and greenhouse gas emissions. In the long run, a positive shock in energy R&D expenditure reduces greenhouse gas emissions, while a negative shock increases them. More importantly, the reducing effect of positive shock is more dominant than the enhancing effect of negative shock in energy R&D. Similarly, it is shown that the reducing effect of a positive shock on ethanol consumption on greenhouse gas emissions is stronger than the increasing effect of a negative shock. After the estimations, this paper presents two critical implications, political and practical. (i) The government's energy R&D expenditures and biofuels have an important role in the fight against climate change and the clean energy transformation process. (ii) Researchers should also consider asymmetric effects when examining energy technologies, renewable energy, and environmental issues. • Examines the greenhouse gas emissions response to government energy R&D expenditures and bioethanol consumption in the US. • Follows an asymmetric and non-linear method. • Confirms the asymmetrical relationships between energy R&D, bioethanol, and greenhouse gas emissions. • Provides implications for environmental quality and the clean energy transition. [ABSTRACT FROM AUTHOR]

In this study, we calculated the water footprint (WF) of second-generation bioethanol and hypothesized that second-generation bioethanol feedstock in response to the gradual depletion of fossil fuels has contributed to exorbitant international oil prices. To resolve these problems, countries worldwide have actively engaged in developing alternative energy plans to reduce their dependence on petroleum. Bioethanol is a critical choose items of biofuels, and increased use of biofuels for transportation is expected to substantially raise the level of competition for freshwater resources. In this paper, Taiwan's second-generation bioethanol demonstration plant is used as an example to calculate the WF of second-generation bioethanol. Using bagasse and rice straw as raw materials, the water footprint are 268.8 L H 2 O/L EtOH and 4674.9 L H 2 O/L EtOH, respectively, which is considerably lower than that of first-generation bioethanol. In this study, we proposed two sources of feedstock that are suitable for future second-generation bioethanol: (1) nonfood crop materials; and (2) domestic waste (e.g., food waste). The results of this study can be used by countries interested in using biofuels to formulate and implement energy policies that will enable them to develop renewable energy sources and simultaneously consider the management and application of water resources. [ABSTRACT FROM AUTHOR]

Abstract: This paper evaluates the effects on profitability of biofuel production if biofuel producers would sell the waste heat from the production to a local district heating system. All analyses have been performed considering four different technology cases for biofuel production. Two technology cases include ethanol production which is followed by by-production of raw biogas. This biogas can be upgraded and sold as biofuel (the first technology case) or directly used for combined heat and power production (the second technology case). The third and the fourth technology cases are Fischer-Tropsch diesel and dimethyl ether production plants based on biomass gasification. Two different district heating price levels and two different future energy market scenarios were considered. The sensitivity analyses of the discount rate were performed as well. In the case of energy market conditions, the profitability depends above all on the price ratio between biomass (used as the feedstock for biofuel production) and crude oil (used as the feedstock for fossil diesel and gasoline production). The reason for this is that the gate biofuel prices (the prices on which the biofuel would be sold) were calculated assuming that the final prices at the filling stations are the same as the prices of the replaced fossil fuel. The price ratios between biomass and district heating, and between biomass and electricity, also have an influence on the profitability, since higher district heating and electricity prices lead to higher revenues from the heat/electricity by-produced. Due to high biofuel (ethanol + biogas) efficiency, the ethanol production plant which produces upgraded biogas has the lowest biofuel production costs. Those costs would be lower than the biofuel gate prices even if the support for transportation fuel produced from renewable energy sources were not included. If the raw biogas that is by-produced would instead be used directly for combined heat and power production, the revenues from the electricity and heat would increase, but at the same time the biofuel efficiency would be lower, which would lead to higher production costs. On the other hand, due to the fact that it has the highest heat efficiency compared to the other technologies, the ethanol production in this plant shows a high sensitivity to the district heating price level, and the economic benefit from introducing such a plant into a district heating system is most obvious. Assuming a low discount rate (6%), the introduction of such a plant into a district heating system would lead to between 28% and 52% (depending on the district heating price level and energy market scenario) lower biofuel production costs. Due to the lower revenues from the heat and electricity co-produced, and higher capital investments compared to the ethanol production plants, Fischer-Tropsch diesel and dimethyl ether productions are shown to be profitable only if high support for transportation fuel produced from renewable energy sources is included. The results also show that an increase of the discount rate from 6% to 10% does not have a significant influence on the biofuel production costs. Depending on the biofuel production plant, and on the energy market and district heating conditions, when the discount rate increases from 6% to 10%, the biofuel production costs increase within a range from 2.2% to 6.8%. [Copyright &y& Elsevier]

Abstract: The emergence of environmental and sustainability regulations, such as Kyoto protocol, Energy Policy Act and the increasingly limited availability of fossil fuels has brought the notion of gradually substituting petroleum products with bioethanol into the limelight. Even though, bioethanol is one of the cleanest sources of energy, a major concern of bioethanol production is its economic feasibility. Industrial symbiosis is one of the sustainable strategies that can help to reduce bioethanol production and logistic costs. In industrial symbiosis, traditionally separate plants collocate in order to efficiently utilize resources, reduce wastes and increase profits for the entire industrial symbiosis and each player in the industrial symbiosis. This paper focuses on developing optimal configurations of bioenergy-based industrial symbiosis under certain constraints, such that the bioethanol production cost (or profit) is reduced (or increased). A decision framework that combines the Linear Programming models and large scale Mixed Integer Linear Programming model is proposed to determine the optimal configuration of bioenergy-based industrial symbiosis and to design the optimal network flows of various products in the bioenergy-based industrial symbiosis. A case study has been conducted to study the efficiency and effectiveness of the proposed model and the results suggest significant increase in profitability for biorefinery plant and the rest of the players in the bioenergy-based industrial symbiosis system. Sensitivity analysis is also conducted to provide deep understanding of the proposed bioenergy-based industrial symbiosis system and to identify the factors that might impact the performance of biorefinery plant in bioenergy-based industrial symbiosis. [Copyright &y& Elsevier]

Sugarcane is a cash crop that has been a significant source of revenue in many countries around the world. In the last few decades, sugarcane mills that were only intended for sugar production were converted into biorefineries. Biorefinery enables the co-production of useful products from the sugarcane wastes such as bagasse, molasses, cane trash, filter mud and vinasse. In certain applications like disposable plates, fly ash, and as reinforcement in polymer composites, bagasse can be directly employed without the need for secondary processing while applications like paper, biochemical, lignosulfonate, vanillin, etc., require secondary processing through the biochemical route involving pre-treatment, acid hydrolysis, and fermentation. Other sugarcane wastes can also be mixed with bagasse to obtain biomethane, bioethanol, and bioelectricity. This article focuses on the recent advancements in such pre-treatment and processing methods employed by the researchers. It also outlines the strategies to co-generate two different products and ways to maximize the product yield and highlights various parameters influencing the process. The challenges that are critical to the sustainability of the sugarcane biorefineries and their mitigations were also discussed. [ABSTRACT FROM AUTHOR]

Abstract: This study presents a possible implementation of a second generation bioethanol production chain within the Province of Siena (Tuscany, Italy) by means of a biorefinery, and its consequences for the regional GHG balance in order to meet the European requirements for partial substitution of 10% bioethanol for gasoline by 2020. According to the last GHG balance of the territory of the Province of Siena, the transport sector represents the main contributor to the overall GHG emissions within the Province. A biorefinery project is hypothesized, fed by residual straw (from the local production of wheat, barley and oat) and residual geothermal heat (from local geothermal power plant) in order to produce bioethanol. The target of the production plant was about 8200 tons/year of bioethanol, representing the amount needed to replace 10% of the gasoline consumed in 2008 in the Province of Siena. The results of the Life Cycle Assessment (LCA) of the entire production chain have been included within the GHG balance of the Province of Siena in order to assess the effect of this substitution. The emissions derived from the production chain have been added to the current gross CO2eq emissions, and the CO2eq avoided, thanks to the substitution of bioethanol, has been subtracted. The main results of this paper are: 1) the territory of the Province of Siena produces enough straw to implement the bioethanol production chain (38,000 tons/year of ethanol out of 147,000 tons/year of straw); 2) the emissions deriving from the entire bioethanol production chain are about 601.51 kg CO2eq per ton of bioethanol produced (about 4932 tons of CO2eq are the emissions associated to the production of 8200 tons of bioethanol); 3) the use of the produced bioethanol in Siena's transport sector could bring about a reduction of 15,393 tons of CO2eq in emissions, equal to 6% of the net CO2eq emissions. [Copyright &y& Elsevier]

Abstract: The methodologies, approaches and indicators for assessing the impacts of freshwater usage are still evolving. The development of the water footprint concept has been an important step in this direction but the existing methodologies mainly assess the quantity of water used rather than the related impacts. Although there is a recognised need to consider the latter, particularly on a life cycle basis, the difficulty is that there are little or no reliable data on water usage in life cycle databases; furthermore, there is no agreed life cycle impact assessment method for estimating impacts related to freshwater use. However, there have been some methodological developments which propose methods for inventory modelling and impact assessment for water use in life cycle assessment. This paper reviews some of these approaches and discusses their strengths and limitations through a case study, which considers the impacts of freshwater consumption from corn-derived ethanol produced in 12 different countries. The results show a huge variation in the results between different methods and demonstrate the need for a standardised methodology for assessing the impacts of water use on a life cycle basis. Specific recommendations for further research in this field have been made accordingly. [Copyright &y& Elsevier]

Abstract: Equating eco-efficiency with the business link to sustainable development is clearly limited, especially with the new paradigms brought up by Corporate Social Responsibility, which has shown that the private sector’s contribution to sustainable development can go far beyond the sphere of pollution control. It is necessary to give eco-efficiency a broader meaning so that it can support the quest for sustainable development. This requires the inclusion of social aspects, leading to a kind of eco-social efficiency. The present paper illustrates this idea by comparing Brazilian production and use of ethanol from sugarcane, in the context of the National Alcohol Program (Proalcool), with biodiesel production and use, in the context of the Biodiesel National Program (PNPB). Despite the problems presented, PNPB was designed to encourage companies to align productivity concerns with social ones, what could be the beginning of the here called eco-social efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Oil shortage and environmental deterioration urge people to pay more and more attention to Biomass-based Fuel Ethanol (BFE), because it is renewable and apparently environmentally friendly. This paper aims to assess and compare the air emissions of three BEF products from different feedstock planting areas in China. For the purpose of a “cradle to grave” study of biomass-based ethanol fuel as a substitute transportation fuel, the authors chose “vehicle fueled by biomass-based E10 (a blend of 10% ethanol and 90% gasoline, v/v)” as the subject. Then, life cycle emission models of Wheat-based E10 from central China, Corn-based E10 from northeast China, and Cassava-based E10 from southwest China were set up based on surveys; life cycle emission functions of CO2, CO, N2O, NO x , SO2, CH4, VOC, and PM10 were constructed and value of each emission category was calculated based on Monte Carlo simulation of the life cycle emission models. The calculation results showed that compared with gasoline-fueled vehicles, biomass-based E10-fueled vehicles release less CO2 and VOC in their lifecycles, but wheat-based E10-fueled and cassava-based E10-fueled ones have more emissions of CO, CH4, N2O, NO x , SO2, PM10 and corn-based E10-fueled ones have more emissions of CH4, N2O, NO x , SO2, PM10. Suggestions on reducing the emissions have been proposed for future actions. [Copyright &y& Elsevier]

Abstract: This paper investigates the possibilities of attaining zero-waste emissions in the case of sugar production. The case-studied sugar plant located in Slovenia reflected a typical plant, using traditional sugar production from beet. An investigation of the possible use of waste and by-products from sugar processing was carried out, in order to approach zero-waste from beet sugar processing. The sugar production process was simulated and optimization was carried out concerning energy utilization. Consumption of energy in the chosen sugar plant was lowered by simultaneous optimization of the evaporation and crystallization process. Changing the fuel type used in the case-studied sugar plant (replacement of heavy fuel oil with natural gas) produced a significant decrease in air emission. Opportunities in the sugar industry have been discovered for adapting to new market conditions through the optimization of combined sugar–ethanol production. The two proposed options have been economically and environmentally evaluated and compared. [Copyright &y& Elsevier]

Within the context of achieving low carbon shipping by 2050, high hopes are placed on alternative marine fuels in addition to a large number of technological and operational measures. A technological review has been carried out in this paper to determine the most promising alternative marine fuels considering the simultaneous reduction of sulphur oxides, nitrogen oxides and carbon dioxide emissions as well as sustainability. Firstly, potential alternative marine fuel options have been summarized based on a review of published literature. Then, key physicochemical properties, feedstocks, production processes, transportation and storage factors, and end uses of zero carbon or carbon-neutral fuels have been analyzed. Finally, a qualitative ranking of the potential of different marine fuel options is presented based on a multi-dimensional decision-making framework. It was found that zero carbon synthetic fuels including hydrogen and ammonia accompanied by clean production could play a vital role in domestic and short sea shipping, though current costs and infrastructure are not commercially feasible. Methanol (fossil/renewable) appears likely to be the most promising alternative fuel for global shipping instead of other carbon-neutral biofuels such as renewable natural gas, bioethanol, biogenic dimethyl ether and biodiesels, which may be feasible for domestic and short sea shipping depending on local practices. It should be highlighted that marine fuel substitution is a prolonged process. Accordingly, consensus-building and action-adopting in the maritime community as early as possible is important to anchor expectations and achieve the goals of clean maritime transportation. • Renewable methanol appears to be the most promising fuel option for global shipping. • Potential of hydrogen and ammonia is mainly in domestic and short sea shipping. • Prospects of alternative marine fuels significantly depend on the world energy mix. [ABSTRACT FROM AUTHOR]

The demand for bioethanol has increased owing to the growing environmental and social concerns. Designing an efficient Bioethanol Supply Chain (BSC) is a precondition for commercializing the bioethanol production. In this regard, this paper proposes a comprehensive Decision Support Tool (DST) integrating Artificial Neural Network (ANN), mathematical modeling, and solution approach to carefully design and optimize a sustainable second-generation BSC while considering economic, environmental, and social aspects. A multi-objective mixed-integer linear programming model is developed for the strategic and tactical design of BSC in which the bioethanol demand is predicted using an ANN model. To solve the proposed multi-objective model, a hybrid approach based on Best-Worst Method (BWM) and Torabi-Hassini (TH) approach is proposed to find the most preferred solution regarding the decision maker's preference towards the objective functions. The applicability of the proposed DST is demonstrated through assessing the impact of two alternative BSC expansion policies on a real case study in Iran. The results demonstrate that adapting an appropriate ethanol distribution policy over a planning horizon could result in a 33% reduction in total costs. Moreover, it is suggested that a 10% increase in the total costs can be beneficial from environmental and social perspectives. • Developed a comprehensive Decision Support Tool (DST) for the design of sustainable Bioethanol Supply Chain (BSC). • Integrated BWM and TH methods for optimizing the BSC considering the decision maker's preference and priorities. • Used the proposed DST to two alternative policies for the establishment of BSC in a national scale. • Provided managerial insights and discussed policy implications. [ABSTRACT FROM AUTHOR]

The world in general, and Cameroon in particular, are facing three major problems which are population increase, natural resource decrease and climate change. This work focuses on assessing the environmental impact of the production of second-generation liquid and gaseous biofuels by means of the life cycle assessment method, in order to contribute to sustainable development with emphasis on environmentally concerned decision-making and appropriate choice of technologies. The increasingly essential Life Cycle Assessment method is at the heart of this work. Avocado, cocoa and peanut residues have been converted on a laboratory scale to second generation gaseous biofuels (biogas) and liquid biofuels (ethanol). Biomethane yields are 177, 127 and 73 mL/g for avocado seed, cocoa pods and peanut shells respectively. When it comes to bioethanol, avocado seed, cocoa pods, and peanut shells produced yields of 178, 61 and 49 mL/kg biomass respectively. Based on the annual production of the three crops, 200,000 kg and 30,376,960 m3 of bioethanol and biomethane respectively can be produced at the national level of Cameroon. The SimaPro software version 9.1.1.1, the Ecoinvent database v.3.6 and the ReCiPe Midpoint impact method v.1.04 were used for the assessment. All categories of resulting environmental impacts are assessed and quantified. The categories with the most significant impacts are land use, global warming, Human non-carcinogenic toxicity, Terrestrial ecotoxicity, Fossil resource scarcity and water consumption observed in the agricultural phase. Global warming, Land use and Terrestrial ecotoxicity are the hot spots observed in the process of converting biomass into bioethanol and biomethane. The main sources of detected impacts are the processes of seed production, the use of electricity, distilled water and chemicals during the process of converting waste to biofuel on a laboratory scale. This laboratory-scale work will serve as a reference for decision-making of pilot plants and then large-scale production of liquid and gaseous biofuels with the objective of promoting the development of a sustainable biomass-energy industry based on avocado seeds, cocoa pods and peanut shells through identification of critical factors. • Agricultural sector is one of the main economic sectors in Cameroon. • Agricultural by-products can be converted in biofuels. • The environmental impacts of the conversion of agricultural biomass are analyzed. • The laboratory scale conversion is discussed compared to conventional fuels. [ABSTRACT FROM AUTHOR]