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The valorization of typical household food waste (HFW) produced at municipality level was studied for the production of electricity in a microbial fuel cell (MFC) from its extract, and methane, through anaerobic digestion of the solid extraction residue. HFW, after heat drying and shredding, was subjected to extraction using warm water, which resulted in a liquid fraction (extract) and a solid residue. The rich in soluble chemical oxygen demand extract was used for electricity production in a four air- cathodes single chamber MFC, operating under different organic loading rates, while the solid residue from the extraction process was used as substrate for methane production in biochemical methane potential experiments. On the basis of the energy outputs estimated for the optimum operational conditions of both aforementioned processes, it can be concluded that the exploitation of dried HFW is quite appealing as it leads to promising energy recovery.

AbstractThis study analyses the relationship between foreign direct investment, economic growth, urbanization, energy use, and carbon emissions in Brazil, Russia, India, China, and South Africa (BRICS countries) between 1990 and 2014. According to the empirical results, both environmental Kuznets curve (EKC) and pollution haven hypotheses (PHH) are confirmed. Urbanization contributes to reducing carbon emissions, while energy use is one of the main driving forces of ascending carbon emissions. The main advance of this paper lies in the moderating effect of foreign direct investment and energy usage on carbon emission in the case of the BRICS. The empirical results confirm a dampening impact of foreign direct investment on energy use, generating a correction in carbon emission. Thus, structural transformations are highlighted with a positive influence on energy efficiency and sustainable growth. It is expected that policymakers must promote renewable sources and boost clean foreign industries in selected host countries.

A general obstacle to the development of perennial grasses is the relatively high cost of propagation and planting. The objective of the present study was to investigate new propagation and planting methods of giant reed (Arundo donax L.), miscanthus (Miscanthus x giganteus Greef et Deuter) and switchgrass (Panicum virgatum L.). Field and open-air pot trials were carried out in four different locations across Europe: hydro-seeding of switchgrass was tested in field trials at the experimental farm of the University of Bologna, Italy; stem propagation and bud activation methods of miscanthus were evaluated in field experiments in Péteri, Hungary; giant reed rhizome and stem propagations were compared in a field trial in Aliartos, Greece; finally, an open-air pot trial was carried out in Catania, Italy, using single-node stem cuttings of giant reed. Hydro-seeding emerged as a feasible and promising technique for switchgrass to ensure prompt seed emergence and weed control during plant establishment. Direct stem plantings of miscanthus were successful, and activated stem-buds were able to sprout in field conditions; however, timely stem transplant was determinant for shoot density and biomass yield. In giant reed, rhizome propagation showed a higher stem density and biomass yield than stem propagation; however, the yield gap was not significant from the second year onwards. Single-node rooting was mainly driven by air temperature. Nodes from basal stems showed higher rooting rates than median and apical ones. Growth regulator pretreatments enhanced rooting rate only at transplanting times under suboptimal air temperatures. In general, these experiments provided insights into propagation strategies aimed at enhancing the establishment phase of perennial grasses.

Abstract A series of laboratory experiments were performed in continuously stirred tank reactors at mesophilic conditions, fed semi-continuously with various mixtures of diluted poultry manure and whey. Co-digestion of whey with manure was proved to be possible without any need of chemical addition up to 50% participation of whey (by volume) to the daily feed mixture. Up to this point, specific biogas production (L/kg VSin) remained roughly unchanged at the various whey fractions added in the feed mixture, mainly due to the lower chemical oxygen demand (COD) of whey compared to that of manure. At whey fractions above 50%, the reactor turned to be unstable, as shown by the considerable decrease in pH and biogas production. The experiments were scaled up to a continuously stirred pilot tank reactor, which had previously been acclimated to poultry manure digestion. Whey was gradually introduced in the feed, at increasing rates, replacing equivalent volumes of manure, in such a way, that total COD of the feed remained constant. For an hydraulic retention time of 18 days at 35 °C and organic loading rate of 4.9 g COD/LR d, it was found that biogas production increased from 1.5 to 2.2 L/LR d (almost 40%). This could be mainly attributed to the higher biodegradability of carbohydrates (main constituent of whey) compared to lipids (main constituent of manure) and to the correction (increase) of C:N ratio.

A combined Lewis-Brønsted acid ethanolysis of sugars was thoroughly investigated with the aim of producing ethyl levulinate (EL) in a single step. Ethanolysis carried out at 453 K for 4 h using H2SO4 (1 wt%) and AlCl3·6H2O (30 mol % with respect to sugars) produced a yield of 60 mol % of EL respect to glucose and starch. Such optimised conditions were positively applied directly on different food waste, preliminarily characterised and found to be mainly composed by simple (10-15%) and relatively complex sugars (20-60%), besides proteins (6-10%) and lipids (4-10%), even in their wet form. The catalytic system resulted robust enough to the point that the copresence of proteins, lignin, lipids and mineral salts not only did not negatively affect the overall reactivity, but resulted efficiently converted into soluble species, and specifically, into other liquid biofuels of different nature.

Geochemical characterization of two landfills, one closed and the other still active, both located near Komotini (Thrace, Greece), has been carried out. The aim was to provide an integrated and reliable methodology for a rapid assessment of the real impact of a municipal solid waste landfill, in the main environmental matrices (air and water) of the surrounding areas. The chemical (CO2, CH4, CO, H2, N2, and O2 + Ar) and isotopic characterization (?13C(CO2) and ?13C(CH4)) of landfill gas and chemical (Na+, K+, Ca2+, Mg2+, Cl-, SO4 2-, HCO3 -, NH4 +, NO3 -, NO2 -, B, COD, Fe, Mn, As, Cr, Ni, Cu, Zn, Cd, Pb, and Hg) and isotopic analysis (?D, ?18O, tritium content, and ?13CDIC) of leachate, stream waters and groundwaters, and flux survey on the air-soil interface has been carried out. Combined chemical and isotopic analysis of the fluids collected inside and in the surroundings of the Komotini landfills supply a detailed picture of biogas emission and composition as well as of leachate chemistry and interaction with local waters. The results arising in this case study demonstrate that it is possible to propose a quick and reliable geochemical protocol to get a detailed picture of the state of health of the environment around a landfill.

This article explores the reasons that affect the decisions of managers of firms to adopt management practices in order to green their supply chain management. Under the context of environmental policy, the relationship between policy instruments (‘command and control’, market-based, and self-regulated) and the decisions of managers to adopt green supply chain management (G-SCM) practices is examined. The results show that in some cases the environmental legislation, market-based instruments and self-regulated incentives could play a critical role in the decisions of managers to adopt some specific G-SCM practices, while in other cases environmental policy instruments have not seemed to affect the decisions of managers regarding some other G-SCM practices.

European seas are experiencing rapid development. The anthropogenic demand for marine resources and space exerts the need for novel concepts for sustainable resource exploitation and smart space allocation. Multi-Use (MU) is an emerging concept to overcome spatial claims and support Blue Growth, however its actual potentials and current status of implementation in different sea basins is to a large extent unexplored. An analytical framework using a mixed method approach is proposed for the identification and analysis of MU potentialities in eight EU countries of the Euro-Mediterranean sea basin. The paper addresses opportunities and challenges of ten existing and potential MU combinations driven by three maritime sectors: tourism, renewable energy and Oil & Gas industry. Opportunities and challenges for MU development were presented in terms of drivers, added values, barriers and impacts. Results show that highest potential for MU development are related to tourism-driven MU combinations (e.g. pescatourism), but also emerging MU potentials exist related to Floating Offshore Wind energy and aquaculture (Gulf of Lion) and the re-use of Oil & Gas decommissioned platforms (Northern-Central Adriatic Sea). Findings were discussed for their geospatial distribution and their policy, socio-economic, technical and environmental boundary conditions. Recommendations on actions to foster MU development in the Euro-Mediterranean sea space are provided.