title: Stabilisation/solidification of APC residues from MSW incineration with hydraulic binders and chemical additives.
abstract: This study focuses on the stabilisation/solidification (S/S) treatment of air pollution control (APC) residues from municipal solid waste (MSW) incineration. Six formulations (T1-T6) were tested based on different cements as binders, for the immobilisation of pollutants and to prevent their entering into the environment at unacceptable rates. Soluble phosphates and silicates were considered in some cases to fix heavy metals. The performance of T1-T6 products was measured in terms of initial and final setting times, mechanical strength, total availability and leaching from S/S products. Two monolithic leaching tests were used to estimate emissions of pollutants over 48h and 64 days. The results showed that the setting time was reduced when soluble phosphates were used. Moreover, although all the treatments have met the threshold of 1MPa for unconfined compressive strength, this parameter was significantly reduced due to matrix dissolution during immersion. After three cycles of leaching, the limit of 10% for solubilisation was exceeded for all treatments with the exception of T5 (with phosphates). This study demonstrated that the S/S treatment used at the industrial level can be improved with respect to toxic heavy metals, by using soluble silicates or phosphates, but not regarding soluble salts.
authors.affiliation: CIEPQPF - Research Centre on Chemical Processes Engineering and Forest Products, Department of Chemical Engineering, University of Coimbra, Rua Sílvio Lima, 3030-790 Coimbra, Portugal. Electronic address: margaridaquina@gmail.com.
authors.forename: Margarida J
authors.initials: MJ
authors.lastname: Quina
authors.affiliation: Department of Chemical and Biological Engineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
authors.forename: João C M
authors.initials: JC
authors.lastname: Bordado
authors.affiliation: CIEPQPF - Research Centre on Chemical Processes Engineering and Forest Products, Department of Chemical Engineering, University of Coimbra, Rua Sílvio Lima, 3030-790 Coimbra, Portugal.
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Quinta-Ferreira
mesh_terms: D000397:Air Pollution / Q000517:prevention & control; D019245:Compressive Strength; D017745:Incineration; D014866:Waste Products / Q000032:analysis*; D014876:Water Pollution / Q000517:prevention & control
chemical_list: D014866:Waste Products
keywords: APC residues; Incineration; Phosphates; Silicates, Leaching; Stabilisation/solidification