No full-text available
To read the full-text of this research,
you can request a copy directly from the author.
Entropie et recyclageQuelques exemples
Abstract
A limit to sustainable development could be the exhaustion of some natural resources. A counterpoint is represented by a global closed-loop replenishing system, but real cycles cannot be completely closed. Concerning material systems a factor of entropy lies in losses of physical properties. However recycling is a way to reduce or slow up entropy of material systems. To reach very high recycling rates, loop recycling, and not only cascade recycling, is needed.
Cases of some materials provide illustration : at first the case of paper (and cardboard) for the year 2000 at an European level (on the basis of data from the European Recovery Paper Council). The case of plastics is surveyed too ; by comparison with paper, their recycling rates are low ; however not only mechanical recycling but also chemical (feedstock) recycling and energy recovery have to be taken into account. Another case is aluminium, with a high recycling rate, and the case of glass has been considered previously (Déchets, Sciences et Techniques n° 13, 1994).
For a global view, the logic in terms of material entropy would have to be supplemented by energy and environmental balances and economic and social aspects.
ResearchGate has not been able to resolve any citations for this publication.
The recovery of households packaging glass (cullet) is expanding in the industrial countries, notably with outlets in the frame of a closed-loop recycling scheme: the bottles are transformed into new bottles. However some questions remain concerning the outlets:
- limits of a closed-loop system when the cullet is not sorted by colours;
- valorisation of tiny pieces of broken glass when it is not desirable to introduce them into the melting furnace;
- valorisation of the cullet in the islands, and in nonindustrial countries, where an industrial recycling plant does not exist.
The objective of this paper is to explore some alternative possibilities of cascade recycling (when closed-loop recycling is not feasible). Moreover a distinction will be made according to the fact that a (re-) melting process is needed or not.
A low temperature (420°–480°C) of pyrolysis minimises the gaseous fraction, and allows liquid and solid fractions of high economic value to be obtained; these include light oils, aromatics, paraffin waxes and monomers.Molten salts, with their excellent heat transfer properties, are interesting media for rapid and regular pyrolysis (problem of reaction kinetics); a eutectic has been selected. Chlorine-containing plastics are also dechlorinated almost completely (using basic salts, which are consumed in the process).The results of laboratory tests on polyethylene, polypropylene, polystyrene and polyvinyl chloride are given.Considering the conclusions of the experiments and the possible economic applications, further developments relating to an industrial stage are discussed.
The article is a revised version of the findings from a research investigation carried out at the Interfaculty Department of Environmental Science, University of Amsterdam, for the Dutch Ministry of Environment (Sirkin and Ten Houten, 1993). The general aim of the research was to investigate the implications and applications of the concept and the principles of cascading (Sirkin, 1990) as a tool for the appropriate design of products and production processes; and furthermore, as a possible foundation for a sustainable resource management policy.Among the questions set out to be answered were the following: (1) What possibilities lie in the application of the cascade concept for the appropriate exploitation of the intrinsic and extrinsic properties of resources, substances, materials and products? (2) What does the appropriate use of resource potential and resource quality mean for the design of products? (3) What examples can be found in industrial practices, product design or in resource utilization systems where the principles of cascading are already applied? (4) Is it possible to apply the principles of cascading at the industrial or company level; and what kinds of problems arise when attempting to do so? How can they be solved? (5) What are the implications of cascading for the concept of integral chain control, and its applications for environmental policy? (6) What are the implications of cascading in relationship to an eventual sustainable resource management policy? And what strategic policy measures can be derived?Answering these questions, and attempting to set cascading into an operational framework within the context of sustainability, required revisions and further development of previously formulated cascade principles. The cascade chain concept, presented in this article, is the result of these revisions. The theoretical foundations of the cascade chain model as a tool for achieving resource sustainability are presented in Part I. Part II presents various examples of cascade systems and discusses the cascade chain implications related to product design, industrial practices and subsequent resource management policies. Part III consists of a summary and conclusions with policy recommendations and recommendations for further areas of investigation. A glossary of terms has been attached at the end of the article.
Entropie et gaspillage, éd. Cujas
- H Guitton
H. Guitton : Entropie et gaspillage, éd.
Cujas, 1975 (165 pages)
Analyse des réemplois, recyclages, valorisations de déchets par l'étude de systèmes cascade
- F Schneider
F. Schneider : Analyse des réemplois,
recyclages, valorisations de déchets par
l'étude de systèmes cascade, Thèse de
Doctorat, INSA de Lyon (LAEPSI),
1996.
La structure du marché des fibres cellulosiques de récupération, Publications économétriques
- G Bertolini
G. Bertolini : La structure du marché
des fibres cellulosiques de récupération,
Publications économétriques, vol. 13,
fasc. 2, 1980 (pp. 1 à 19).
Récupération -recyclage des papiers-cartons : le jeu de la réincarnation
- G Bertolini
G. Bertolini : Récupération -recyclage des papiers-cartons : le jeu de la réincarnation, Environnement et Technique
n° 139, 1994 (pp. 12 et 71).
Homo plasticus ; les plastiques, défi écologique, éd. Sang de la terre
- G Bertolini
G. Bertolini : Homo plasticus ; les
plastiques, défi écologique, éd. Sang de la
terre, 1991 (270 pages).