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Abstract Anaerobic digestion of lignocellulosic biomass appears to be an efficient process for the production of energy whilst answering present-day environmental challenges. However, lignin contained in lignocellulosic biomass is hardly biodegradable, thus representing a major obstacle for maximum methane production. Consequently, although pretreatments need to be considered, their cost is a limit for their full-scale use. Biological pretreatments are a cheaper alternative in this context. Several biological pretreatments have been studied for anaerobic digestion: ensiling, partial composting, specific microbial consortia, enzymes and fungi. Simple, inexpensive and efficient pretreatments can be obtained using fungi. White-rot fungi (WRF), have been considered as most capable of delignifying a substrate. However, their use in the pretreatment of substrates for anaerobic digestion is quite recent and still needs to be investigated. This review compares fungal pretreatment with other biological treatments for anaerobic digestion of lignocellulosic biomass. Enzymatic mechanisms for WRF pretreatments are then exposed. The literature data regarding the improvement of anaerobic digestibility with WRF pretreatment are summarized (anaerobic digestion and in vitro digestibility with rumen microorganisms). Finally, lignocellulosic biomass features allowing the improvement of anaerobic digestion are exposed (porosity, cellulose crystallinity, etc.). The possible effects of WRF on these characteristics are discussed and industrial perspectives for WRF pretreatments are presented.

The last few decades have seen an unprecedented increase in global bioenergy production. China, India, Japan, and South Korea are currently Asia's largest energy consumers with fast-growing economies and populations. However, energy supply in these countries mostly depends on imported fossil energy. Their response has involved significant efforts to find alternative energy sources, including massive investments in bioenergy development. Apart from energy security issues, this study identifies rural energy access and climate change issues as the key drivers behind bioenergy policies. The results show how different driving forces and obstacles, such as food security and feedstock issues, have led these countries to establish their own pathways to bioenergy development. Lastly, the paper develops additional bioenergy development challenges, such as the impacts of changes in land use and bioenergy competition, which constitute potential obstacles to bioenergy expansion and ultimately need to be considered by policymakers.

This chapter review aims at developing a clear understanding of the impacts and benefits of conservation agriculture (CA) with respect to climate change, and examining if there are any misleading findings at present in the scientific literature. Most of the world’s agricultural soils have been depleted of organic matter and soil health over the years under tillage-based agriculture (TA), compared with their state under natural vegetation. This degradation process can be reversed and this chapter identifies the conditions that can lead to increase in soil organic matter content and improvement in soil health under CA practices which involve minimum soil disturbance, maintenance of soil cover, and crop diversity. The chapter also discusses the need to refer to specific carbon pools when addressing carbon sequestration, as each carbon category has a different turnover rate. With respect to greenhouse gas emissions, sustainable agricultural systems based on CA principles are described which result in lower emissions from farm operations as well as from machinery manufacturing processes, and that also help to reduce fertilizer use. This chapter describes that terrestrial carbon sequestration efficiently be achieved by changing the management of agricultural lands from high soil disturbance, as TA practices to low disturbance, as CA practices, and by adopting effective nitrogen management practices to provide a positive nitrogen balance for carbon sequestration. However, full advantages of CA in terms of carbon sequestration can usually be observed only in the medium to longer term when CA practices and associated carbon sequestration processes in the soil are well established.

An environmental friendly process was developed to produce Arthrospira maxima's biomass from sugarcane vinasse, which was generated in a bioethanol production chain, at laboratory and pilot scale. Peptides fractions were than obtained from enzymatically hydrolyzed biomass. High microalgae biomass productivities were reached (0.150 g L-1 day-1) coupled with a significant reduction of BOD and COD (89.2 and 81%, respectively). Three peptide fractions were obtained from microalgae biomass through single or sequential enzymatic hydrolysis. Antioxidant, antimicrobial, anti-inflammatory, and/or anti-collagenase activities of biopetides' fractions were observed. The PHS showed multi-biological activities. The three peptides fractions could be potential candidates for different applications in pharmaceutical, cosmetic and food industry.

Résumé Les transports génèrent de nombreuses externalités, dont celles liées à la pollution atmosphérique. Cet article analyse deux d’entre elles, les gaz à effet de serre et la pollution locale, qui, en général, sont étudiées séparément dans les travaux sur les politiques optimales de transport. Ici, ces externalités sont analysées conjointement grâce à un modèle de prise de décision séquentielle. Celui-ci permet de tenir compte de l’irréversibilité des politiques menées ainsi que de la possibilité d’une diminution progressive des incertitudes grâce à l’arrivée d’informations supplémentaires. Nous trouvons que des mesures structurelles qui permettent de limiter le recours aux transports privés sont économiquement plus avantageuses que des dispositifs techniques qui réduisent les émissions de substances polluantes. L’utilité de cette analyse conjointe des externalités est illustrée à travers deux cas : les dispositifs fiscaux qui grèvent l’automobile et la politique du logement. Classification JEL : C6; D62; D81; R48.

This paper presents the integration of the Kalina cycle process in a combined heat and power plant for improvement of efficiency. In combined heat and power plants, the heat of flue gases is often available at low temperatures. This low-grade waste heat cannot be used for steam production and therefore power generation by a conventional steam cycle. Moreover, the steam supply for the purpose of heating is mostly exhausted, and therefore the waste heat at a low-grade temperature is not usable for heating. If other measures to increase the efficiency of a power plant process, like feed-water heating or combustion air heating, have been exhausted, alternative ways to generate electricity like the Kalina cycle process offer an interesting option. This process maximizes the generated electricity with recovery of heat and without demand of additional fuels by integration in existing plants. The calculations show that the net efficiency of an integrated Kalina plant is between 12.3% and 17.1% depending on the cooling water temperature and the ammonia content in the basic solution. The gross electricity power is between 320 and 440 kW for 2.3 MW of heat input to the process. The gross efficiency is between 13.5% and 18.8%.