Physical and chemical characterization of construction, renovation and demolition waste in the Quebec province

Abstract

• Characterization of construction, renovation and demolition debris was completed. • Physical and chemical methods were performed as pre-treatment approach. • Results indicated that the debris were highly contaminated. • Sulfates were concentrated in the passing of 2.36 mm fractions. • The distribution of heavy metals and HAPs were homogeneous for all size fractions. The residues from construction, renovation and demolition activities represent one of the highest volumes of waste in the world. Due to the absence of source separation activities on construction sites and the lower quantities of waste that can be sent to a sorting center in comparison to the quantities produced, the management of the construction, renovation and demolition debris (CRDD) has become an important challenge for scientists. The space constraints and the high cost of management are examples of the problems associated to these wastes. Multiple researchers have studied potential CRDD treatment and valorization approaches, but the characterization of these wastes has not been largely discussed, although thought to be essential. In the present study, physicochemical characterization of CRDD was carried out for three sampling sites located in the Quebec province and this was done during three periods within 2019–2020. It was found through sieving that the passing of 2.36 mm fractions represents 66% of the total weight of CRDD. Moreover, from 63% to 93% of sulfates was concentrated in the passing of 2.36 mm fractions for all the sampling sites. As confirmed by the ratio of S-total/S-SO 4 for inferior 2.36 mm fractions, the total sulfur was found as soluble sulfates. The distribution of heavy metals and polycyclic aromatic hydrocarbons (PAH) was relatively stable and was lower than the accepted concentrations by Quebec regulations (Protection of soils and rehabilitation of contaminated lands and residual fertilizer materials (RFM)) for certain fractions. The present study confirmed that the characterization is an essential step before applying any treatment or valorization approach to CRRD. Depending on the contaminant concentrations, different valorization approaches could be adopted.