Indicators to assess the recovery of natural resources contained in demolition waste
Demolition waste materials are one of the major industrial waste deposits in many countries and represent an important quantity of potential resources that are not exploited, because the major part of these wastes go to landfill. Indeed, recycling or recovery of demolition waste can reduce the need of primary natural resources. This article gives indicators and a method to analyse demolition waste management with regard to the use of resources contained in these wastes. Demolition wastes are characterized by their contents in energy and raw materials. This content is quantified on the basis of the sum of energy and raw materials necessary for the construction of the building considering the non-renewable character of materials contained in wastes. In fact, this content represents the environmental investment which was necessary to construct the building. An energy balance and a mass balance, with this concept of 'raw material and energy' content, can allow a strategy of waste management to be determined in order to salvage the most important parts of energy and raw materials contained in demolition waste, and so identify the strategy which permits a maximum fraction of the initial environmental investment to be saved. Five waste management scenarios concerning building demolition were assessed with this method and these indicators, and the results are presented in this article.