An investigation on the recycling of hydrated cement from concrete demolition waste. (August 2015)

• Record Type: Journal Article
• Authors: Gastaldi, D.; Canonico, F.; Capelli, L.; Buzzi, L.; Boccaleri, E.; Irico, S.
• Is Part Of: Cement & concrete composites. Volume 61(2015)
• Page Start: 29
• Page End: 35
• Publication Date: 2015-08
• Subjects: Hydrated cement waste -- Recycled aggregate -- Concrete demolition waste -- Fine fraction -- CO2 reduction; Composite-reinforced concrete -- Periodicals; Concrete -- Periodicals; Composite materials -- Periodicals; Composites de ciment -- Périodiques; Béton -- Périodiques; Composites -- Périodiques; Béton léger -- Périodiques; Cement composites; Composite materials; Composite-reinforced concrete; Concrete; Lightweight concrete; Periodicals; Electronic journals; 620.135
• DOI: 10.1016/j.cemconcomp.2015.04.010
• Languages: English
• ISSNs: 0958-9465

Abstract

Abstract: Construction and demolition waste (CDW) recycling is generally limited to the use of the coarser fraction as aggregate for new concrete. The recovery of fine aggregates requires a cleaning by removing the hydrated cement waste (HCW). In this paper, the possibility to use HCW extracted from CDW as alternative component for the production of new clinker is explored. A pure HCW sample was prepared and used in partial replacement of natural materials in raw admixtures for new clinker production. At a replacement degree of 30%, a new Portland clinker containing almost 50% of C3 S could be produced with a huge spare in the release of CO2 (about 1/3 less). At higher HCW dosage a non-Portland clinker containing almost 80% of C2 S has been obtained: its use as supplementary cementing material in blended cements revealed satisfying long term performances.