| Environnement, ingénierie & développement |  |
N°4 - 4ème Trimestre 1996
1. Éditorial n°4 Déchets Sciences et Techniques: Premier bilan
Avec ce quatrième numéro, Déchets, Sciences et Techniques achève sa première année d'existence. Au nom de la rédaction, je tiens à remercier très sincèrement tous ceux qui n'ont pas hésité à nous adresser des articles, qui plus est de qualité, comme en attestent les nombreux échos qui nous parviennent des lecteurs.Le plus difficile est toutefois à venir dans la mesure où c'est dans la durée que sera reconnue la réputation de la revue.En premier lieu, le pari de faire coexister à leur niveau d'expression le plus élevé des articles relatifs à un large spectre de disciplines scientifiques se doit d'être poursuivi car il représente la seule façon de rassembler des données exhaustives et validables sur le thème des déchets. Analystes, physicochimistes, biologistes, économistes, thermiciens, sociologues, complètement ou temporairement engagés dans des recherches sur les déchets sont, à ce titre, vivement encouragés à nous soumettre des textes afin d'élargir encore plus le panel des équipes publiantes.En second lieu, il apparaît que le champ d'exploration du problème des déchets ne se limite plus aux seules techniques de traitement et qu'il s'étend de façon notoire à des problématiques comme la relation entre le traitement des déchets et la santé, l'évaluation du comportement à long terme des matières solidifiées ou bien encore les outils de gestion des risques écotoxiques, […]
2. Valorisation énergétique des ordures ménagères par incinération : Etat des lieux et projets
Energy from wastes takes an important part of the domestic refuse treatment by local authorities. lncineration with energy production will hardly increase du ring next years, according to a law (1992) which aims to ensure that within ten years (by 2002), no domestic refuse will be accepted into landfills without disposal. ln 1995, 80 incineration plants with energy recovery (UIOM) were in action, and about 30 plants were planned or under construction. Energy is recovered by means of district heating or electricity sol to Electricité de France. Amorce, association of French local authorities and public and private companies working in waste management, conducted a survey on ail the existing or planned incineration plant. This survey was conducted in order to know some technical and economical ratios, aiming to:- give some basic informations to the owners and managers of the 80 existing incineration plants, allowing themto compare with each other.- give those informations to the autorities and companies wich are planning new incineration plants.- set out a national assesment regarding energy from domestic waste, in order to estimate its part into the french energetic system. Before this survey, nobody had sufficient datas about technical, economical and energetical aspects of energy from waste sector in France. This survey was conducted during 1995 summer by a young ingenior student of École des mines de Nancy, and was half subsidised by French Energy and Environnement Agency […]
3. Détermination des formes du carbone organique dans les déchets. Application aux mâchefers d'ordures ménagères (MIOM)
This study proposes a reliable alternative to the loss on ignition. Several specific analytical technics and the preparation of the samples are tested on MSW incineration bottom ashes. The carbon dry oxidation methods with a sensible detector for C02 are the best suited.
4. Valorisation des mâchefers d'incinération de déchets en technique routière: Évaluation de leur comportement en condition réelle d'utilisation
As part of the bottom ash research Program conducted by CREED, a pilot road section has been constructed at Briec in Brittany, in October, 1995. The road surface is about 1 800 m2, and bottom ash from municipal solid waste incineration has been substituted for natural gravel in the sub-base layer. The geotechnical characteristics of the bottom ash used were analyzed from their production until their utilization at the site. Since the bottom ash quality is amenable to use in low-traffic roads, no particular precautions are necessary during the road construction. The bottom ash environmental parameters are being checked regularly for 18 months after the road construction. The results so far show that the percolation samples have concentrations, for minerals and organics parameters, near the maximum acceptable concentrations for potable water.
5. Stabilisation des résidus solides de l’incinération par le procédé TREDI-ASH: Étape 1 : traitement des mâchefers
lncineration of industrial wastes produces slags which, according to the future French regulations, will require to be stabilized prior to disposal. Portions of heavy metals contained in slags could indeed be solubilized and therefore constitute a toxic mobile fraction which has to be eliminated. Tredi-ASH is a chemical leaching process (exchange reaction with CaCI2, obtained from wet gas cleaning neutralization) used to extract mobile metal pollutants from slags. This process allows to detoxify and to stabilize an important fraction of slag's original weight (70 to 95% dry weight), reducing ultimate waste volume without transfer of pollution. Sludges generated by stirring and leaching (5 to 30% dry weight) can be recycled on waste incineration plants, to neutralize acid waters originating from wet gas cleaning.
6. Utilisation de champignons filamenteux pour la dépollution de sols pollués par des polluants organiques
Filamentous fungi exhibit interesting abilities to remediate soils polluted by organic chemicals. This paper presents firstly the main fungal properties useful in remediation, then the research areas to develop, and finally the first results obtained by the authors.
7. Modélisation des transferts de matière en milieu poreux: Modèle couplé dissolution/diffusion
Leaching tests are essential in the environmental assessment of stabilized wastes. Research programs are conducted on their interpretation in order to develop tools for the evaluation of long term release of pollutants contained in solidified wastes.
8. Biooxydation de minéraux sulfurés et dissolution de métaux par la bactérie acidophile : Thiobacillus Ferrooxidans
The commercial extraction of metals from ores by microbial leaching turns to account the iron oxidation capabilities of Thiobacillus ferrooxidans. The iron oxidation involves an electron transfer chain localized in the periplasmic space of the cell. The characterization of the redox proteins involved the determination of their physiological role, together with genetic engineering programs, could have implications to increase the leaching capacity of these bacteria.
9. Caractérisation minéralogique, chimique et spéciation des métaux lourds dans les boues de la station d'épuration de la ville de Marseille
Characterization of sewage sludges of Marseille show the presence of dominant mineral phases: calcite and quartz, of traces: iron oxides and amorphous iron introduced by FeCl3 added to sludges and of organic matter. Speciation of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) in sludges show that carbonates, iron oxides and organic matter are retention phase of these metals and trap them during wastewater treatment.
10. Supervision en temps réel des stations d'épuration des effluents industriels
The development of dedicated tools and techniques for real-time supervision of industrial waste water treatment plants is described, applied to the surface treatment industries. The paper presents a few aspects of an expert system for real-time supervision and fault detection. The goal of the project is the design of information and decision support systems, in order to improve the operation (security, reliability, efficiency) of waste water treatment plants.
11. Le traitement des déchets spéciaux du bâtiment
Housing Hazardous wastes have been listed in a recent study carried out by CEBTP. A near national and official wastes classification would be published. The CEE guideline for dangerous materials has been arrested as reference. The waste disposai and the specific treatments are outlined.
12. Incorporation de déchets argileux dans les bétons de bois: Propriétés mécaniques et thermiques
The authors have developed technologies to recycle clay waste by making insulating materials. ln this paper they give mechanical and thermal performances. The influence of thermohygrometric conditions has also been studied and it showed that in normal conditions of working, the thermal conductivity is not considerably moved by the thermohygrometric conditions. The experimental results compared to those obtained for aerated autoclaved concrete and plaster show the possibility to design technically good materials from clay waste.