| Environnement, ingénierie & développement |  |
N°3 - 3ème Trimestre 1996
1. L’outil gestion des déchets ménagers d'Ecobilan
Ecobilan has developed a software tool designed to assess the environmental burdens of any collection-sorting-downstream treatment scheme of any domestic waste. The tool allows any comparison between alternative waste management scenarios, including incineration, recycling, landfilling. A special emphasis is put on the user's interface, which enables easy and quick navigation through the tool. The construction of the system and the calculations are automatically performed upon request by TEAMTM, Ecobilan's Life Cycle Assessment software tool. Sets of graphics can be generated and give insight into the inventory of the flows (around 150 are listed) and into a large set of environmental impacts (around 20 can be computed).
2. Dispositifs d'étanchéité par géosynthétique bentonitique au C.E.T. des Hautes Gayeulles (Rennes)
The geosynthetics clay liner are factory manufactured products use for as hydraulic barriers, consisting of a small permeability bentonite layer sandwiched between geotextiles and/or geomenbrane, wich are held together by stitches, needlepunching or adhesive. A « Bentomat » GCL (needlepunched) was used as liner, cover and on the stopes of the waste landfill of Hautes-Gayeulles. lt is presented here a description of the liner systems, the quality control of the GCL, its placement and the field testing performed on the cover.
3. Valorisation de boues d'exploitation de granite
Waste resulting from sawing and burnishing operations on granites is not used at the present time and is a nuisance for environment. ln this paper, waste resulting from granites from the whole world have been studied. The choice has been made to transform them into materials with low environmental impact. The authors give the mechanical characteristics of the elaborated bearing and insulating materials.
4. Éditorial n°3 Déchets Sciences et Techniques
Les micro-polluants ou « contaminants chimiques » métaux lourds, pesticides organochlorés, PCB, nitrates, dioxines etc. sont considérés à juste titre comme une préoccupation sérieuse par les spécialistes de l'environnement et les pouvoirs publics. Ils sont pour beaucoup d'entre eux très persistants dans les milieux naturels, peuvent s'accumuler dans les chaînes alimentaires et présenter des risques à long terme, notamment sur les fonctions de reproduction voire sur le patrimoine génétique (risques cancérogènes). Il est donc indispensable de fixer des normes strictes vis-à-vis de ces produits dans les milieux ou les aliments, de surveiller leur évolution, de détecter leurs provenances et de les contrôler.Il me semble toutefois que dans les mentalités collectives y compris dans le milieu scientifique et médical, se fixent sur ces polluants « insidieux » (suivant le terme consacré} des réactions irrationnelles (peur du « chimique », besoin de trouver des boucs émissaires ...), qui font parfois oublier des choses simples et perdre le sens de la hiérarchisation des risques.
5. Recherche sur les déchets en économie et en sociologie ; un état de l’art: Partie 2. Approches sociologiques
The article gives an overview (axes, some content and bibliography) of research on waste problems in economics and sociology. Waste has to be related not only to zero or negative economic value, but also to a whole system of socio-cultural values. The economic approaches are referring notably to the externalities and their internalization, scientific basement of environmental standards, instruments of regulation, public sector and industrial economy. The sociological approaches are referring to the behavior of social groups, psycho-sociological representations and logics of social actors, social forces and their dynamics. Research applies mainly on firms (in particular eco-industries), waste generation and management, separate collection, disposal options and the Nimby syndrome.
6. Écocompatibilité des déchets : vers une prise en compte de la notion d'impact pour l’élimination et la valorisation des déchets
Disposal conditions or re-use of waste are still defined on regulation and technical basis depending on the best available and economically acceptable technology. Current regulations take into account the notion of impact on the environmental receptors only to a very limited extent. This article describes the principle and the first results of a three year research program, initiated by the French Agency of Energy and Environment (Ademe), called « Ecocompatibility program » aiming to introduce progressively a logic of impact in the waste management. The assessement of the waste ecocompatibility is based on the comparison of the flow of the waste pollutants (in a specified scenario) and the flow of pollutants considered as acceptable by the different environmental receptors (water or soil) concerned. The first work conducted by the teams involved in this program was to identify and hierarchize the numerous factors of influence and the parameters of characterization to be considered for this assessement. An experimental program of tests to be performed at the labscale and on a full scale during the second an the third year of the elaborated program.
7. Étude des risques biologiques des déchets de cabinets médicaux
Biological investigations were made in the country of the Rhône in France, on refuse from consulting rooms of practitioners. Concentrations of indicator bacteria (total aerobic and anaerobic bacteria, total coliforms, faecal streptococci, Escherichia coli), of some pathogenic or opportunistic bacteria (Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, Aspergillus niger), and some viruses (HBV, HCV, HIV) were made. The refuse from medical consulting rooms showed differences in microbiological properties, with variations from 0 CFU/ml to 69.106 CFU/ml. Usually the highest counts of micro-organisms were found in the refuse from veterinarians consulting rooms (until 69.1O6 CFU/ml). As compared to the municipal refuse, medical consulting rooms refuse had lower microbial counts (10 to 103 less). Pseudomonas aeruginosa were only identified in refuse from medical consulting rooms of veterinarians and general practitioners, and Candida albicans were found in refuse of gynaecologists (800 CFU/ml), and dentists (S CFU/ml). Tests for viruses were negative. The results of this study show that the risk of contamination from those kind of medical refuse is no more important than the one from municipal refuse.
8. L’inventaire du cycle de vie pour rationaliser et optimiser la gestion des déchets ménagers
Sustainable development requires a rational use of resources and an efficient management of waste. Consequently, waste management should be both economically and environmentally sustainable. Until recently, no tools were available to evaluate the sustainability of municipal solid waste systems. This gap is now being filled, and this article presents one tool that can be of use: life cycle inventory (LCI) for solid waste management. Several versions of this tool are now available; this paper focuses on the book and software created by Procter & Gamble. We will describe the methodology used, define the objectives and limitations of the inventory, and apply it to a couple of real-life examples. Both municipalities and the waste industry will now be able to make an overall economic and environmental evaluation of waste management systems, to support their choices and policy in this area. lt will also be possible to propose improvements for existing systems, by identifying their weaknesses.