Cement, Energy and Environment

21 Fig. 4 represents the individual diffractogram of EOF slag with phase identification and phase quantification data. The quantitative analysis was performed by Rietveld analysis using the ICSD database (ICSD:161510, PANICSD:98-016-1510). The identified crystalline phases and their quantities are as follows. Quartz (SiO2): 28.1 %; Magnetite (Fe3O4): 18.1 %; Magnesoferite (MgFe2O4): 7.7 %; Calcium Iron Oxide (Ca2Fe9O13): 7.1 %; Dicalcium Silicate (2CaO, SiO2): 15.4 %; Tricalcium Silicate (3CaO.SiO2): 2.3 %; Calcium Diiron Oxide’ (CaFe2O4): 4.5 %; Brownmillerite (Ca2Fe2O5): 12.8 %; Zeolite: 4 %. Among those identified phases dicalcium silicate and tricalcium silicate offer hydraulic binding properties, whereas zeolite provides significant pozzolanic reactivity in cement hydration reactions (Zheng 2023). Hence the XRD analysis suggests that GEOFS has the potential to be a supplementary cementitious material. 3.3 EVALUATION OF PHYSICAL PARAMETERS ACCORDING TO INDIAN STANDARD (IS 4031) The developed blended cement (PSC 1 to PSC 5) was analyzed for different physical parameters according to Indian Standard (IS: 4031). Table 3 and Fig. 5 have demonstrated the results accordingly. Normal Consistency (N.C) of the blended cement (PSC 1 – PSC 5) are 28.0 %, 26.75 %, 26.75 %, 26.5 %, 26.5 % and 26.75 % respectively (Table 3). The slightly lower N.C of all PSC 2 to PSC 5 (N.C>27) than PSC 1 (N.C: 28) indicates that the addition of GEOFS causes a slight reduction of water demand in developed blended cement. Le-Chatelier and autoclave expansion studies have demonstrated (Table 3) very negligible extent of expansions (within the permissible limit as per IS: 4031) for all the grades [limit of Le-Chatelier expansion: 10 mm (Max.), the limit of Autoclave expansion: 0.8 % (Max.)]. The determined setting times (initial and final) of the developed cement have shown that the addition of GEOFS did not affect the normal setting of PSC Cement (Table 3). Figure 3: X-ray diffractograms of GGBS, Clinker, and GEOFS. Figure 4: X-ray diffractogram of GEOFS with phase identification and quantification data.