Manufacture of high-grade calcined lime (calcium oxide) manufactured from ‘gas fired vertical shaft lime kiln’. This new technology of calcined lime produces a high-grade product, which is devoid of any external impurities (such as carbon, silica, sulphur, etc. added in the case of mix-fuel domestic kilns - burning of coal with limestone) enabling us to have CaO 95%, SiO2 & MgO less then 1%. No traces of Sulphur & Carbon