| 摘要 |
<p>The invention relates to a process for preparing lime and pure carbon dioxide by the decarbonization of calcareous powder or limestone in a cylindrical horizontal rotary kiln using a granular mass resistant to a temperature of 1,100A C as a thermal medium. In order to completely separate the pure carbon dioxide resulting from the decarbonization from the remainder of gases resulting from the fuel combustion, in a first compartment related to the kiln, granules heated at a temperature of 1,050A C transfer the heat to the raw calcareous material while it is vigorously stirred, the resulting carbon dioxide and the mixture of granules and lime powder having a temperature of 930A C being discharged from said compartment. The cooled lime powder is separated on a rotary screen and the granules separated from the mixture are transferred to a second compartment wherein they are heated up to a temperature of 1,050A C with the gaseous fuel and the preheated comburant. The hot granules are subsequently transferred into the first decarbonizing compartment, the cycle being resumed.</p> |
