A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Valorisation of water treatment sludge for lightweight aggregate production
Highlights Water treatment sludge (WTS) is incorporated to expanded clay for LWA production. The expanding properties of LWA are slightly reduced with WTS addition. LWAC formulated with commercial LWA is similar to LWAC with LWA containing WTS. WTS can be revalorised by LWA production.
Abstract Water treatment sludge is an industrial by-product which has recently been classified as a waste by the European Commission. The main goal of this work is to valorise this waste to produce lightweight aggregates. Formulations with sludge substituting expanded clay up to 50 wt% were produced. The physical properties of the lightweight aggregates such as bloating index, density and porosity were studied. The introduction of the sludge without expanding properties, reduced the expandability of the clay and the porosity of the aggregates. The density increased from 0.32 g/cm3 in aggregates without sludge to 1.46 g/cm3 in aggregates with 50 wt% of sludge. It is shown that lightweight aggregates can be produced using mixtures of expanded clay and water treatment sludge, with low substitution percentages (up to 15 wt% of sludge). Aggregates up to 15 wt% of sludge were further studied. The compressive strength increased with sludge wt.%, and the concentrations of heavy metals and metalloids, assessed through leaching tests, were well below the stablished limits. Two preliminary tests of lightweight aggregate concrete were produced: LWAC 1 was formulated with commercial lightweight aggregates and LWAC 2 with aggregates containing 7 wt% of the sludge and commercial lightweight aggregates. The physical, mechanical and thermal properties of LWAC 1 and LWAC 2 were found to be very similar. Our work demonstrates the feasibility in using water treatment sludge as a by-product to produce lightweight aggregates suitable for thermal insulation and lightweight applications.
Valorisation of water treatment sludge for lightweight aggregate production
Highlights Water treatment sludge (WTS) is incorporated to expanded clay for LWA production. The expanding properties of LWA are slightly reduced with WTS addition. LWAC formulated with commercial LWA is similar to LWAC with LWA containing WTS. WTS can be revalorised by LWA production.
Abstract Water treatment sludge is an industrial by-product which has recently been classified as a waste by the European Commission. The main goal of this work is to valorise this waste to produce lightweight aggregates. Formulations with sludge substituting expanded clay up to 50 wt% were produced. The physical properties of the lightweight aggregates such as bloating index, density and porosity were studied. The introduction of the sludge without expanding properties, reduced the expandability of the clay and the porosity of the aggregates. The density increased from 0.32 g/cm3 in aggregates without sludge to 1.46 g/cm3 in aggregates with 50 wt% of sludge. It is shown that lightweight aggregates can be produced using mixtures of expanded clay and water treatment sludge, with low substitution percentages (up to 15 wt% of sludge). Aggregates up to 15 wt% of sludge were further studied. The compressive strength increased with sludge wt.%, and the concentrations of heavy metals and metalloids, assessed through leaching tests, were well below the stablished limits. Two preliminary tests of lightweight aggregate concrete were produced: LWAC 1 was formulated with commercial lightweight aggregates and LWAC 2 with aggregates containing 7 wt% of the sludge and commercial lightweight aggregates. The physical, mechanical and thermal properties of LWAC 1 and LWAC 2 were found to be very similar. Our work demonstrates the feasibility in using water treatment sludge as a by-product to produce lightweight aggregates suitable for thermal insulation and lightweight applications.
Valorisation of water treatment sludge for lightweight aggregate production
Mañosa, J. (author) / Formosa, J. (author) / Giro-Paloma, J. (author) / Maldonado-Alameda, A. (author) / Quina, M.J. (author) / Chimenos, J.M. (author)
2020-10-13
Article (Journal)
Electronic Resource
English
Manufacturing of artificial lightweight aggregate from water treatment sludge
| European Patent Office | 2023
Application of water treatment sludge in the manufacturing of lightweight aggregate
| Online Contents | 2013
Application of water treatment sludge in the manufacturing of lightweight aggregate
| British Library Online Contents | 2013
Valorization of washing aggregate sludge and sewage sludge for lightweight aggregates production
| British Library Online Contents | 2016