| 摘要 |
PURPOSE: To obtain a high quality slaked lime free from impurities accumulated on its surface layer, prevented in the presence of a left industrial salt, reduced in bulk density, and enhanced in porosity. CONSTITUTION: Natural lime 1 is mixed with an industrial salt and subsequently subjected to a high temperature calcination treatment in a reducing atmosphere. The surface layer of the produced small massive reduced salt calcined lime 13 is ground off with a grinder 14, and the left reduced salt calcined and shaved lime 15 is subjected together with a theoretical digestion amount of ion exchange water 17 to a hyclrothermal hydration treatment in a closed high pressure digestion machine 16 to obtain the high quality calcined lime 18. A solid carbon material 12 comprising coal and coke is used as a fuel for calcining the lime 1, and an alkali or alkaline earth salt such as sodium chloride, potassium chloride, magnesium chloride or calcium chloride is used as the industrial salt. The elevated temperature, the elevated pressure and the reaction-completion time in the closed type high pressure digestion machine are 150200 deg.C 10-20 (kg/cm<2> ), and 7-10hr, respectively. |
