also increases the belite and
gehlenite phase. However, there is an excess sulfate compound
left behind in clinker. The addition of sulfate ion to the calcia–
aluminosilicate system can generate larnite phase due to a
reaction preference of sulfate ion to aluminium ion [7]. In the
presence of a large amount of sulfate ion that has sufficient free
silica coming from fly ash and free CaO coming from FGDgypsum