Construction, renovation and demolition (CRD) wastes contaminated by gypsum residues: Characterization, treatment and valorization.

Management of wastes resulting from construction, renovation and demolition (CRD) activities has become an important challenge for scientists. The recovery of gypsum residues from CRD waste is one of the solutions to minimize the impact of CRD operations on the environment. This review discusses the characteristics of CRD waste, different treatment and valorization methods for both CRD waste and extracted gypsum residues. Pre-treatment based on particle size separation is the most fundamental step in the process of extracting gypsum residues from CRD fine tailings. The subsequent application of a physical, chemical or biological decontamination approach on the gypsum residues could significantly improve its quality as compared to natural gypsum. The quality of the gypsum obtained affects its valorization potential in different sectors such as cement manufacturing, the sequestration of carbon dioxide and nutrients. The valorization strategy could help reducing emissions of greenhouse gases while producing by-products that can be reused in agriculture. As such, this review may provide guidance for more sustainable management of CRD and gypsum residues in the future.