C asinine is the term used for thermal decomposition of solids, e. g CacO3=Cao+ cO2 and is frequently done in rotary kilns. These types of reactions are usually endothermic and fuel must be burnt to sustain them Both roasting and calcining are shrinking core type reactions (see next slide)Calcining... …..is the term used for thermal decomposition of solids, e.g. CaCO3 = CaO + CO2 and is frequently done in rotary kilns. These types of reactions are usually endothermic and fuel must be burnt to sustain them. Both roasting and calcining are shrinking core type reactions (see next slide)