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Sustainability of agro-food supply chains has recently become the subject of greater interest from consumers, firms, governmental organizations and academia as the environment continues to deteriorate. One of the most critical factors influencing the sustainability of an agro-food supply chain is its network design. A particularly challenging aspect in this context is the broad range of influencing indicators associated with the Triple Bottom Line (TBL) of sustainability that need to be considered. However, many of these indicators could not be fully integrated or measured by single-step optimization problems. This paper presents a critical literature review of operational research methods for the design of sustainable supply chains. A novel two-stage hybrid solution methodology is proposed. In the first stage, a partner selection is performed using a hybrid multi criteria decision making based on Analytic Hierarchy Process (AHP) method and the Ordered Weighted Averaging (OWA) aggregation method. The result obtained in the first stage is used in the second stage to develop a multi-objective mathematical model to optimize the design of the supply chain network. This approach allows the simultaneous consideration of all three dimensions of sustainability including carbon footprint, water footprint, number of jobs created and the total cost of the supply chain design. The proposed approach generates a Pareto frontier to aid users in making decisions. Numerical experiments are completed utilizing data from an agro-food company to demonstrate the efficiency and effectiveness of the proposed solution methodology. The analyzes of the numerical results provide important organizational, practical and policy insights on (1) the impact of financial and environmental sustainability on supply chain network design (2) the tradeoff analysis between environmental emission, water footprint, societal implications and associated cost for making informed decision on supply chain investment.

Two studies conducted in Guadeloupe (West Indies) and Réunion (Indian Ocean) islands were designed to investigate the benefits of producing sugarcane as an energy crop and to assess the influence of agroclimatic factors on energy efficiency, respectively. In this context, it is essential to know the low heating value of the dry above-ground biomass (LHVd, MJ/kg) and its energy yield (EY, MJ/m2) in order to select the best varieties and set up a payment method for growers. Eighteen Poaceae (sugarcane and Erianthus) cultivars were compared under wet tropical environmental conditions in Guadeloupe. Three sugarcane cultivars were studied in four contrasting environments in Réunion. The partition sampling and biomass measurement procedures were identical at both locations. Low heating value (LHV) predictions were achieved using near-infrared reflectance spectroscopy (NIRS) after specific calibration (Guadeloupe), or arithmetically after lignocellulosic compound prediction (Réunion). In both studies, LHV variability was very low and slightly dependent on the site, cultivar and above-ground biomass components (millable stalks and tops, and green and dead leaves). Considering the overall dry above-ground biomass (DAB, kg/m2), the LHVd was calculated by averaging 159 samples (mean 16.65 MJ/kg) in Guadeloupe and 315 samples (mean 16.45 MJ/kg) for Réunion. An excellent linear relationship between the DAB and its EY, regardless of cultivar, age and environment, was found (n = 474 and R² = 0.99). Sugarcane energy content assessment could thus be simplified by measuring the DAB, while enabling development of a faster method of payment for growers based on the DAB measurement and the correlation between DAB and EY. Finally, the findings of this study should allow growers to rapidly determine the commercial value of their sugarcane crops, and also enable purchasers to assess the amount of recoverable energy. (Résumé d'auteur)

A theoretical analysis of a compression/ejection hybrid cycle for domestic refrigeration is presented in this paper. In this cycle, an ejector is employed to reduce the loss of available energy due to the large temperature difference between the fresh food section and the freezer section. A theoretical model is established and simulated with FORTRAN. Thermodynamic properties of working fluids are obtained with the package REFPROP, version 8.0. The performance of this system using several refrigerants (R123, R124, R141b, R290, R152a, R717, R600a, and R134a) is presented. The results show that the entrainment ratio and the coefficient of performance depend mainly on the fluid nature and the operating conditions. According to the results of simulation of the hybrid cycle using several refrigerants, the ejection cycle can reach a higher coefficient of performance compared with the standard cycle. R141b gives the most excellent performances.

Heavy metal emission is a great environmental concern for the development of municipal solid waste (MSW) thermal treatment techniques. In this study, both experimental investigations and theoretical simulations are carried out to identify the partitioning of heavy metals between the gaseous phase and solid fractions during pyrolysis, gasification, and incineration of simulated MSW. Two types of incinerators are used. A tubular furnace is applied to evaluate the evaporation of metals from residues, whereas the metal distribution among bottom ash, cyclone fly ash, and filter fly ash is further examined in a fluidized bed. Six target metals (Cd, Pb, Zn, Cu, Cr, and Ni) are studied. Results show that a reductive atmosphere favors the evaporation of Cd and Zn but refrains Cu, Ni, and Cr volatilization, because metals are mainly reduced to their elemental form or sulfide, according to thermodynamic equilibrium calculation. Oxides are the dominant species under oxidizing condition due to the abundance of alkalis...

Abstract Biogas is a valuable renewable energy that can be used as a fuel or as raw material for the production of hydrogen, synthesis gas and chemicals. Apart from its main constituent of CH 4 and CO 2 , it also contained various undesirable contaminants. The removal of these contaminants such as H 2 S will significantly improve the quality of the biogas for further use. This work involved the valorization of calcium carbonate (CaCO 3 )-based solid wastes for the removal of H 2 S from the biogas stream. The solid wastes were analyzed by different physicochemical methods CaCO 3 was found as the main component of both solid wastes, while trace amounts of other elements such as Mg, Al, etc. were also present. The solid wastes were dispersed in water and the resulted suspensions were tested for the removal of H 2 S from the gas phase, using a triphasic gas/liquid/solid glass reactor at room temperature and pressure. A commercial activated carbon (AC) and a pure commercial calcite were also used for comparison purpose. In addition, mixtures of AC with CaCO 3 waste in different ratios were also tested. The influence of the matrix of gas (air or biogas) on the removal of H 2 S was evaluated. Both solid wastes showed higher performance compared to the pure commercial calcite for H 2 S removal. The coupling of a CaCO 3 waste and AC allowed improving the sorption performance compared to pure commercial CaCO 3 and AC used alone. The results obtained open a new promising way for the valorization of CaCO 3 -based wastes for H 2 S removal from biogas.

Microbial anodes were formed under polarization at -0.3 V/SCE on graphite plates in effluents from a pulp and paper mill. The bioanodes formed with the addition of acetate led to the highest current densities (up to 6A/m(2)) but were then unable to oxidize the raw effluent efficiently (0.5A/m(2)). In contrast, the bioanodes formed without acetate addition were fully able to oxidize the organic matter contained in the effluent, giving up to 4.5A/m(2) in continuous mode. Bacterial communities showed less bacterial diversity for the acetate-fed bioanodes compared to those formed in raw effluents. Deltaproteobacteria were the most abundant taxonomic group, with a high diversity for bioanodes formed without acetate addition but with almost 100% Desulfuromonas for the acetate-fed bioanodes. The addition of acetate to form the microbial anodes induced microbial selection, which was detrimental to the treatment of the raw effluent.

Abstract The article presents design problems of tourist infrastructure in protected landscape and nature areas in Poland. They concern discrete regulation of the intensity and course of leisure and tourist traffic towards and within protected areas. Such regulation can only be carried out on the basis of the structure of accessibility of areas covered by protection and spatial development plans, shaped in accordance with environmental conditions. The quality of access to protected areas is also significantly influenced by the architecture of tourist infrastructure objects presented in the article. It concerns selected objects of small wooden architecture designed in areas with special landscape and natural requirements, which have been implemented in Poland in recent years. These objects are small elements, e.g. signposts, information and educational boards, benches, tables, waste bins, rest shelters, objects at entrances to protected areas (gates), ticket offices, as well as impressive engineering structures built in difficult terrain conditions, e.g. terraces, platforms and observation towers. These issues will be presented on the basis of many years of research and design works concerning protected areas in Lower Silesia (arch. Bogusław Wojtyszyn) and original designs (arch. Alicja Maciejko and arch. Mirosław Strzelecki) realised on the tourist routes of the Stolowe Mountains National Park in Poland, shaping tourism and recreation accessibility for all users including disabled people in protected landscape and nature areas.