Gamma-C₂S Synthesis from Fly Ash of Fluidize-Bed Boiler for CO₂Capture

Abstract

This paper describes the CO2 capture performance of cement blended paste incorporating gamma-dicalcium silicate (gamma-C2S) made with industrial by-products, by taking into consideration of eect of CaCO3, y ash replacement ratio under the sintering process. X-ray diraction method was conducted in order to quantitatively investigate the gamma-C2S content. CO2 capture performance of mortar sample incorporating gamma-C2S was investigated by means of compressive strength test using accelerated carbonation chamber. The experimental results revealed that the kind of CaCO3 would aect the aect the formation of gamma-C2S after the sintering with respect to the XRD-Rietveld analysis. Moreover, it is conrmed that compressive strength of mortar sample incorporating gamma-C2S has the same tendency at curing age of 3, 7 and 28days. Blended mortar sample made with 10 wt.% replacement ratio of gamma-C2S had high compressive strength value compared to normal mortar sample, therefore, incorporating gamma-C2S had a positive eect on the compressive strength after accelerated carbonation. Finally, the waste foundry sand powder may be alternative to produce gamma-C2S.

New scientific evidence of the effect of high temperatures and long curing times on MK-blended cement paste mineralogy

“…Both ( and ) dicalcium silicate phases form during clinker manufacture, when the material is burnt at 550 °C. The lower reactivity of the -C2S phase would explain its unchanging proportion in the total mineralogy of all the cements analysed, even after 15 years [53].…”

Hardening Properties of Foamed Concrete with Circulating Fluidized Bed Boiler Ash, Blast Furnace Slag, and Desulfurization Gypsum as the Binder

“…Figure 1 shows the results of X-ray diffraction analysis of each material used in this study. As a result of the X-ray diffraction analysis, peaks of CaO, CaSO 4 and Fe 2 O 3 were detected in the CFBA2, and an amorphous peak and peak of anhydrite were detected in the BFS. In addition, peaks of CaO, Calcite, Anhydrite, and Quartz minerals were confirmed in DGS.…”

Screening Out Reactivity-Promoting Candidates for γ-Ca2SiO4 Carbonation by First-Principles Calculations

“…The Fe and Mg ions in olivine can be substituted by Ca ions without destroying the symmetry of the crystal. The olivine Ca 2 SiO 4 that belongs to the orthorhombic crystal system is also one of the polymorphs of belite (β-Ca 2 SiO 4 ), known as γ-dicalcium silicate (γ-Ca 2 SiO 4 ) (Naa et al, 2015). Previous studies have shown that among common olivine minerals, γ-Ca 2 SiO 4 has a significantly dominant surface water absorption capacity (Kerisit et al, 2013), suggesting the potentially high carbonation reactivity.…”