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International audience; To inform the modelling of organic waste treatments yielding organic amendments and fertilisers in France, published as 'Screening LCA of French organic amendments and fertilisers' [1], we compiled data pertaining to the chemical characteristics of both raw and treated organic residues, as well as inventory data on the most common organic waste treatments. The majority of these life cycle inventory data was obtained from reports and other literature, but primary data was also compiled, notably for commercial organic fertiliser production. The data presented here can be used by future life cycle assessment studies on organic waste treatments, as well as to inform agricultural modelling. © 2019 The Author(s)

3rd International Workshop on Geoelectrical MonitoringGELMON 2015, Vienna, AUT, 24-/11/2015 - 26/11/2015; International audience; Anaerobic digestion (AD) has a high growing potential worldwide due to its combined environmental benefits such as reducing greenhouse gas, producing renewable energy, organic amendment and fertilizer. In France, 400 plants were recorded in 2015 which mainly handle agricultural residues using both liquid and solid state processes. The successful and efficient degradation of organic matter in AD needs balanced physical-chemical conditions for microbial development. Moisture content in the media, particularly, was found to be of great importance. Nevertheless, no information is available on the hydrodynamics of the circulation of the leachate through cattle manure or other agricultural residues. Moreover, agricultural residues and mixtures are particularly porous and heterogeneous and no data was found on the efficiency of those systems to humidify homogeneously such a substrate. The hydrodynamic flow characteristics and transfer time of the leachate are essential to design the optimal liquid injection system that will permit to reach uniform moisture content. Already applied in landfills for in-situ characterization of leachates flow through municipal solid waste (MSW), ERT was proven to give reliable results. The results led to the enhancement of the leachate injection system design and enriched the knowledge of MSW behavior. The non-intrusive, non-destructive and 3 dimensional response of the ERT method seems adapted to the study of the leachate infiltration through agricultural effluents in a SSAD plant. We present the first results of the use of 3D time-lapse electrical resistivity tomography performed during a leachate injection in a waste deposit cell in France (20 m3 of leachate was injected during 10 h). 72 electrodes and a Syscal PRO resistivity meter was used. For the inversion, the apparent resistivity have been interpreted taking into account (i) the boundary condition of the waste deposit cell (insulating boundary around the waste deposit cell) and (ii) the effects of temperature (indeed between the surface and the bottom of the waste deposit cell , we measured the variation of temperature in the range of +/-25 °C). The result highlighted the conductive character of this porous media with a resistivity included between 0.5 ohm.m and 10 ohm.m depending on the saturation state; we will show that the infiltration is clearly located by electrical resistivity tomography and that this media is very heterogeneous with complex infiltration shape. The first results suggest the interest of the 3D electrical resistivity tomography to study injection leachate injection in a SSAD plant.

In order to identify the function of uncultured microorganisms in their environment, the SIMSISH method, combining in situ hybridization (ISH) and nanoscale secondary ion mass spectrometry (nanoSIMS) imaging, has been proposed to determine the quantitative uptake of specific labelled substrates by uncultured microbes at the single cell level. This technique requires the hybridization of rRNA targeted halogenated DNA probes on fixed and permeabilized microorganisms. Exogenous atoms are introduced into cells and endogenous atoms removed during the experimental procedures. Consequently differences between the original and the apparent isotopic composition of cells may occur. In the present study, the influence of the experimental procedures of SIMSISH on the isotopic composition of carbon in E. coli cells was evaluated with nanoSIMS and compared to elemental analyser-isotopic ratio mass spectrometer (EA-IRMS) measurements. Our results show that fixation and hybridization have a very limited, reproducible and homogeneous influence on the isotopic composition of cells. Thereby, the SIMSISH procedure minimizes the contamination of the sample by exogenous atoms, thus providing a means to detect the phylogenetic identity and to measure precisely the carbon isotopic composition at the single cell level. This technique was successfully applied to a complex sample with double bromine - iodine labelling targeting a large group of bacteria and a specific archaea to evaluate their specific (13)C uptake during labelled methanol anaerobic degradation.

Quoique l'utilisation agricole des déchets ou produits organiques (déjections animales, boues, composts) apparaisse intuitivement comme une pratique bénéfique pour l'environnement, la démonstration objective du bien-fondé environnemental des filières de gestion biologique se révèle difficile, tant sur le choix des critères à prendre en compte que sur l'évaluation de ces critères. Le travail présenté ici visait à rassembler les connaissances de base nécessaires à la réalisation d'évaluations environnementales globales du type " analyse de cycle de vie " de ces filières. Autant que possible, toutes les catégories d'impact potentiel, ainsi que toutes les étapes de traitement ont été considérées, y compris la phase suivant le retour au sol des produits. L'étude a comporté deux phases : la collecte des données disponibles dans la littérature sur les rejets et consommations de substances et d'énergie associés à ces différentes étapes, puis la mise en cohérence des valeurs retenues pour chaque facteur d'impact dans un format directement utilisable par les outils d'évaluation environnementale. Globalement, au regard de la grande sensibilité des facteurs d'impact à la nature des produits ainsi qu'aux conditions de traitement et de milieu (température, type de sol), les connaissances disponibles s'avèrent souvent beaucoup trop partielles en termes, à la fois, d'acquisition de données en conditions réelles et de compréhension des phénomènes mis en jeu. / The organic recovery of biodegradable waste intuitively appears to be environmentally sound. However, this assumption in favour of biological waste management is not easy to justify objectively, owing both to the choice of comparison criteria to consider and to the valuation of these criteria. The work presented here aimed at gathering the basic data necessary to perform global environmental assessments (like life cycle analysis) of biological waste treatment. As much as possible, all potential impact categories, along with all different stages of treatment were taken into account, including the stage following land application. The study consisted, firstly in collecting in literature obtainable data on the consumption and rejects of matter and energy associated to this different stages, and secondly in compiling the data retained for each impact factor in a form directly useable in environmental assessment tools. Globally, considering the huge sensitiveness of impact factors to the nature of substrates and to the treatment and background conditions (temperature, soil type), the available data appear to be much too scarce, both in term of on-site data acquisition and of the understanding of the underlying mechanisms.

La gestion des déchets ménagers et assimilés s'appuie sur les activités de collecte et de traitement qui sont produites sur des territoires dont l'arrangement s'avère complexe. L'analyse de l'intercommunalité, observée sur les régions Bretagne et Pays de Loire, montre que la situation évolue depuis 1992 sous l'effet des lois relatives aux déchets et à l'organisation intercommunale, avec des différences départementales fortes. / The management of municipal solid wastes based on the activities of collection and the treatment, which are produced in areas where arrangement is complicated. After focusing on the intercommunality of Brittany and Pays de Loire, we noticed that the situation has been moving since 1992, due to the laws about wastes and intercommunality.