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Food waste is becoming a major global concern especially in developing and underdeveloped countries. Vegetable and food waste biomass is continuously generated in huge amounts. Its major impact on the environment is the generation of greenhouse gases. Food wastes are generated at different stages like production, handling, storage, processing, as well as consumption. First-generation technologies used for food waste disposal include landfill, incineration, and composting. But these strategies are not satisfactory for food wastes since they produce toxic methane gas and bad odor and have slow reaction kinetics. This can be addressed to a certain extent by adopting alternative strategies of food waste valorization by converting wastes to value-added products like fuels and chemicals. Food waste valorization will provide a green process with least environmental impact. This chapter discusses the latest trends in food waste valorization for the production of fuels and chemicals.

The energy demand is increasing as well as the GHG emissions and the fossil fuels depletion. Public awareness on this topic significantly raised up in last decades. Nowadays conversion of residual biomasses in energy represents a real opportunity. However, the sustainability of such fuels has to be proven: Life Cycle Assessment is usually used for that purpose. Because of the increasing natural gas demand, scientists are searching for new gasification techniques and among them the hydrothermal gasification is extremely promising. In this chapter, the LCA of such a technology is presented. Contributions of land use change is highlighted. The chapter evaluates and compares effects of different allocation methods of raw material and it points out a rigorous approach for economic allocation. Furthermore, a section is devoted to the end of the plantation life and its consequence on carbon stock and GHG emissions. When the process is correctly integrated 1 MWh of heat and 16.06 kg of equivalent fertilizer are got by hydrothermal way with a significant reduction of impacts. Moreover, the climate change impact is cut down up to 91% and the fossil depletion decreases up to 96%. The study underlines the great dependency of impact reduction to allocation methods: thus, reduction percentages are 80% GHG emissions and 85% fossil depletion compared to the reference system.

The use of methods to assess environmental performances of industrial products became popular in the sixties with the growing environment concerns. The life cycle assessment (LCA) emerged in the 1990s as a response to the need of a more structured methodology and inherited from the REPA – Resource and Environmental Profile Analysis. From the beginning LCA was supported by strong efforts of standardization led by the Society of Environmental Toxicology and Chemistry (SETAC) and the International Organization for standardization (ISO). This chapter introduces LCA methodology based on the four-stage approach popularized by ISO. Its theoretical background is presented as well. The strengths and weaknesses of the methodology are discussed and a new allocation approach is proposed. Extension of environmental Life cycle assessment to social, economic and organizational LCA is outlined. Finally, the chapter concludes with a presentation of the perspectives of LCA development towards an integrated Life cycle sustainability.

Assessing the effect of land-use change (LUC) induced by biofuel policies on greenhouse gas (GHG) emissions required coupling and adapting models to address the complex interaction linking biofuels with agricultural and energy markets and the global scope of LUC. Coupling economic-spatial and biophysical models allowed to address iLUC GHG emissions from biofuels, which magnitude range between 10 and 340 gCO2eq/MJ, depending on the feedstock and origin, the models, assumptions an data used, the biofuel scenarios and the amortization period of GHG emissions. Despite the improvement in modelling this effect, large uncertainty is still linked to the estimation. iLUC factors have being introduced in the US biofuel regulation. The EU however is still deciding the approach to include LUC GHG emissions into biofuel regulation. The development of proper standards for calculating LUC GHG emissions from biofuels as well as the improvement of current methods and data are important to achieve more accurate estimates. The LUC effects of biofuel policies need to be addressed in a broader perspective of sustainable agriculture, land-use, industrial and energy systems.

A large volume of solid and liquid waste is generated due to industrial and urban/suburban/agricultural activities. Management and handling of waste generated is nowadays burning issue for local authorities not only in urban areas, i.e., municipalities, but also in other regions in any country. With increasing urbanization and industrialization, generation of waste/wastewater appropriate disposal, treatment, and/or recycling are posing more challenges as the treatment and disposal costs huge amount in terms of money. However, conceiving the fact that “waste” word is placed wrongly and that it is a resource, resource recovery from wastes has emerged as thrust area of research and management as it offers huge environment and social sustainability potentials. Current researches globally are focusing on the recovery of various resources such as energy, bioproducts, nutrients, metals from waste/wastewater generated by anthropogenic activities, etc. This information needs to be discussed in the present context, and the future perspectives should be explored; most importantly, it should reveal current status, with state-of-the-art information and possibilities for technological exploitation. This chapter elaborates the recovery of various resources from solid and/or liquid waste.

There is a need to explore alternative energy sources to meet the future energy demand in a sustainable way. Algae could be a potential feed stock for biodiesel and other co-products such as animal feed and chemicals. Life cycle assessment (LCA) of such production system has to be assessed before any implementation at commercial scale. In this context, a prospective LCA of algae biorefinery considering selected multi-products (biodiesel, protein and succinic acid) was carried out to estimate the environmental impact compared to a reference system. LCA results revealed less CO2 emissions and land use for biodiesel, protein and succinic acid production system compared to that of only biodiesel and protein production system from algae. The impact reduction was even more when compared with conventional diesel, soy protein and fossil based succinic acid system. A higher carbohydrate composition in algae favors less CO2 emissions and fossil fuel consumption in the algae system compared to that of the reference system. (C) 2015 Elsevier Ltd. All rights reserved.

This paper aims to perform a real options valuation of fusion energy R&D programme. Strategic value of thermonuclear fusion technology is estimated here based on the expected cash flows from construction and operation of fusion power plants and the real options value arising due to managerial flexibility and the underlying uncertainty. First, a basic investment option model of Black-Scholes type is being considered. Then, a fuzzy compound real R&D option model is elaborated, which reflects in a better way the multi-stage nature of the programme and takes into account the imprecision of information as one of the components of the overall programme uncertainty. Two different strategies are compared: "Baseline" corresponding to a relatively moderate pace of fusion research, development, demonstration and deployment activities vs. "Accelerated" strategy, which assumes a rapid demonstration and massive deployment of fusion. The conclusions are drawn from the model calculations regarding the strategic value of fusion energy R&D and the advantages of accelerated development path. (C) 2010 Elsevier Ltd. All rights reserved.

In recent times, demand for energy has significantly increased due to the depletion of fossil fuels and the fast-industrial revolution. This has created a wide space for the development of sustainable and renewable energy sources. Biodiesel has attained exceptional contemplation among other biofuels due to the use of renewable and low-cost resources. Selection of suitable catalyst plays a vital role in biodiesel production by a catalytic transesterification reaction. Compared to homogeneous catalysts, heterogeneous catalysts are most preferred as they have high selectivity and stability with increased biodiesel yield. Heterogeneous catalyst has made incredible development in biodiesel production under mild operating conditions and has less impact on the environment. Nanocatalysts are the effective heterogeneous catalyst, which has brought a tremendous revolution in biodiesel production in recent years. Thus, present review provides a comprehensive analysis of the use of heterogeneous catalyst, importance and challenges associated in biodiesel production. (c) 2020 Elsevier B.V. All rights reserved.

Biomass, Biofuels, Biochemicals: Biofuels: Alternative Feedstocks and Conversion Processes for the Production of Liquid and Gaseous Biofuels, Second Edition, provides general information, basic data and knowledge on one of the most promising renewable energy sources—liquid and gaseous biofuels—and their production and application. The book delineates green technologies for abating environmental crisis and enabling the transformation into a sustainable future. It provides date-based scientific information on the most advanced and innovative technology on biofuels, as well as the process scale-up and commercialization of various liquid and gaseous biofuels, detailing the functional mechanisms involved, various operational configurations, influencing factors and integration strategies. All chapters have been updated, with new chapters covering topics of current interest, including sustainability and biohydrogen.

This paper is focused on the analysis of spillover benefits of the ongoing R&D programme on thermonuclear fusion technology. The spillover effects are understood here as positive externalities of publicly funded R&D, demonstration and deployment (RDDD) activities that may be revealed at the companies' level in the form of newly created knowledge stock; development of innovative products/processes with broader market applications; strengthening of R&D, manufacturing and marketing capabilities; etc. An integrated compound real options model is proposed that allows to estimate the strategic net social present value of fusion RDDD programme taking into account the different types of spillover benefits along with the hidden real options value arising due to uncertainty and managerial flexibility. It was found that the value of spillover effects, modelled as "expansion option", could represent a significant proportion of the overall socio-economic value of fusion RDDD programme (nearly 20%). This paper clearly demonstrates that, besides a high-level mission to assure sustainable energy supply, fusion RDDD programme may yield substantial net socio-economic benefits that may be at least two times higher compared to the expected RD&D costs, and hence the pursuit of even more ambitious programme is economically justified. (C) 2011 Elsevier Ltd. All rights reserved.

Cellulose nanomaterials are developing nowadays as a promising environmental friendlier biomaterial that can be extracted from native plant sources. These materials, because of their excellent physico-chemical and biological properties, urged much interest in biomedical applications. In this paper, a detailed review of nanocellulose is provided with special emphasis on greener production, demands, bio-properties and innovative application in some selected biomedical fields such as tissue implants, drug delivery systems, wound healing and biosensor applications. The current state of global commercial nanocellulose based products and their future potentials for biomedical applications are also discussed. (C) 2021 Elsevier B.V. All rights reserved.

Global increase in the human population and life-style changes have led to enormous development in various industries, including beverage industry. Among the innumerable beverage industries, wineries have received increasing attention and consideration due to various health related benefits and involvement of agricultural materials. Winery industry produces huge quantities of waste materials in the form of solid and liquid wastes. Disposal of these residues (wastes) in the environement is a serious concern and has attracted increasing R&D efforts for their utilization in sustainable manner. Several existing treatments available for winery wastes not environmental-friendly and are even expensive. Usually, combined or hydrid treatment methods have been advocated to achieve the complete utilization of these wastes and among these, bio-based treatment processes have been in much focus for attaining environmental suutaibility in particular. Accordinglt, this review mainly focuses on the application of biorefinery concept for sustainable winery waste management as it is expected that such bioprocesses would be of great impliactions for bioeconomy with furture developments. The review also highlights the advanced techniques for the bioconversion of winery wastes and articulates the major associated challenges.

Petroleum is produced by thermal decay of buried organic material over millions of years. Petroleum oilfield ecosystems represent resource of reduced carbon which favours microbial growth. Therefore, it is obvious that many microorganisms have adapted to harsh environmental conditions of these ecosystems specifically temperature, oxygen availability and pressure. Knowledge of microorganisms present in ecosystems of petroleum oil reservoirs; their physiological and biological properties help in successful exploration of petroleum. Understanding microbiology of petroleum oilfield(s) can be used to enhance oil recovery, as microorganisms in oil reservoirs produce various metabolites viz. gases, acids, solvents, biopolymers and biosurfactants. The aim of this review is to discuss characteristics of petroleum oil reservoirs. This review also provides an updated literature on microbial ecology of these extreme ecosystems including microbial origin as well as various types of microorganisms such as methanogens; iron, nitrate and sulphate reducing bacteria, and fermentative microbes present in petroleum oilfield ecosystems.

Crude glycerol, one of the ever-growing by-product of biodiesel industry and is receiving the closest review in recent times because direct disposal of crude glycerol may emerge ecological issues. The renewability, bioavailability and typical structure of glycerol, therefore, discover conceivable application in serving the role of carbon and energy source for microbial biosynthesis of high value products. This conceivable arrangement could find exploitation of crude glycerol as a renewable building block for bio-refineries as it is economically as well as environmentally profitable. In this review, we summarize the uptake and catabolism of crude glycerol by different wild and recombinant microorganism. The chemical and biochemical transformation of crude glycerol into high esteem malic acid by various microbial pathways is also additionally discussed. An extensive investigation in the synthesis of high-value malic acid production from various feed stock which finds applications in cosmeceutical and chemical industries, food and beverages, and to some extent in the field of medical science is also likewise studied. Finally, the open doors for unrefined crude glycerol in serving as a promising abundant energy source for malic acid production in near future have been highlighted. (C) 2019 Elsevier B.V. All rights reserved.

The gut microbiome, often referred to as "super organ", comprises up to a hundred trillion microorganisms, and the species diversity may vary from person to person. They perform a decisive role in diverse biological functions related to metabolism, immunity and neurological responses. However, the microbiome is sensitive to environmental pollutants, especially heavy metals. There is continuous interaction between heavy metals and the microbiome. Heavy metal exposure retards the growth and changes the structure of the phyla involved in the gut microbiome. Meanwhile, the gut microbiome tries to detoxify the heavy metals by altering the physiological conditions, intestinal permeability, enhancing enzymes for metabolizing heavy metals. This review summarizes the effect of heavy metals in altering the gut microbiome, the mechanism by which gut microbiota detoxifies heavy metals, diseases developed due to heavy metal-induced dysbiosis of the gut microbiome, and the usage of probiotics along with advancements in developing improved recombinant probiotic strains for the remediation of heavy metal toxicity.

Lignocellulosic biomass feedstocks are considered to be one of the major alternatives to fossil- and food-based transport fuel and chemicals, for reasons such as fuel/food security, depleting fossil reserves, climate change, mitigating of pollution in agriculture and rural socioeconomic development. In highly populated and agriculture-based countries such as India, the conventional lignocellulosic feedstock such as rice straw and wheat straw are a major source of animal feed and hence nonconventional feedstock that could be cultivated in wasteland has to be explored to fulfill the lignocellulosic feedstock supply in the coming years. In this context, this study deals with life cycle assessment (LCA) of vetiver, a nonconventional lignocellulosic feedstock for bioethanol and biochemical production in India. A prospective LCA was performed to compare the environmental impacts of a vetiver-based biorefinery system with a conventional system. The results reveal that the carbon dioxide and fossil oil consumption could be reduced by 145% and 77% respectively in the case of bioethanol production, and 30% and 12% respectively in the case of bioethanol and furfural production compared to its reference system. The sensitive analysis indicates that using vetiver biomass as a source of energy in a biorefinery plant further reduces the carbon dioxide emission and fossil oil consumption significantly by 100% and 60% compared to the coal used for the process energy requirement in a vetiver biorefinery.