RESUMEN
Since a decade, numerous industrial and public initiatives have been launched in order to make knowledge, practices and mentalities evolve in relation to the acceptability of using waste instead of raw material as construction product. The objectives of these initiatives have been to evaluate current practices and to make new solutions and beneficial use channels emerge. At the same time scientific and standardisation communities have developed methodologies and tools to fit with the assessment needs expressed by industrialists and public decision-makers. In spite of that, some factors, some of them being cross-linked, make the perpetuation of beneficial use channels or even the concretisation of research projects difficult. To cope with this situation, in the framework of sustainable development applied to natural and alternative material, the French Directorate of Road has launched a project aiming at providing public contracting authorities with a document gathering both technical and environmental requirements that they can prescribe in public market tender calls to promote the use of waste and out-of-technical-specifications-material. This paper deals with the presentation of this project focusing more specifically on the approach to assess both technical and environmental acceptability of waste and out-of-technical-specifications-material to be used as alternative material in road construction in France. The current European situation is first described and this paper finally discusses briefly the other key aspects--than environmental acceptability--that have to be taken into account to succeed waste beneficial use.
Asunto(s)
Materiales de Construcción/normas , Ingeniería/tendencias , Ambiente , Eliminación de Residuos/métodos , Francia , Mercadotecnía , Control de Calidad , Eliminación de Residuos/legislación & jurisprudencia , Riesgo , TransportesRESUMEN
Lead consumption in Europe is 2.054 M tonnes/year, more than 70% of which is produced by recycling and, more specifically, the recycling of car batteries. This industry is jeopardised by the method employed so far, recycling by alkaline fusion, because the treatment produces 200,000 tonnes of toxic and unstable slag. The study presented here attempts to clarify the approach and the combined tools employed (mineralogy, chemistry, leaching, thermodynamics), to construct a coherent physicochemical model of slag behaviour. The model was then used to carry out sensitivity analyses with various landfill scenarios, and to propose adjustments to the process to recover the residual heavy metals and to upgrade as secondary raw products the co-products generated by the inerting of the slag.