The Immobilisation of Heavy Metals from Sewage Sludge Ash in CO<sub>2</sub>-Cured Mortars

Sewage treatment processes are a serious environmental threat due to the difficulties involved in its waste management and disposal. Therefore, one developing trend in sewage sludge processing is its thermal treatment, which generates sewage sludge ash that may contain many environmental pollutants,...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Erick Grünhäuser Soares, João Castro-Gomes, Mateusz Sitarz, Tomasz Zdeb, Izabela Hager
Formato: article
Lenguaje:EN
Publicado: MDPI AG 2021
Materias:
Acceso en línea:https://doaj.org/article/8e258046d513488c9fbfa57535235f34
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:Sewage treatment processes are a serious environmental threat due to the difficulties involved in its waste management and disposal. Therefore, one developing trend in sewage sludge processing is its thermal treatment, which generates sewage sludge ash that may contain many environmental pollutants, such as heavy metals. Moreover, due to the European Union requirements that not only focus on the waste generation reduction but also on its reuse and final disposal, it is essential to pursue new applications of such resources, such as the waste-based material incorporation into alternative cementitious materials. Thus, this study evaluated the heavy metals leachability of CO<sub>2</sub>-cured mortars incorporating sewage sludge ash as filler. For this purpose, Portland cement, reactive magnesia, and electric arc furnace slag were used to produce three different CO<sub>2</sub>-cured mortars, which were cured though pressurised accelerated carbonation curing for 24h. These mortars presented up to 12.7 MPa as compressive strength and their carbonation was confirmed by TG-DTG and FT-IR analyses. Their leachability of heavy metals met the European requirements for all waste materials, including inert materials, and post-industrial wastewater. Therefore, the immobilisation of heavy metals in this binding technology may be considered an effective method to safely manage sewage sludge ash.