Influence of the origin of limestone on its decomposition temperature and on the specific heat capacity and conductivity of lime
Mónica Silva, Eckehard Specht, Jürgen Schmidt and Janan Al-Karawi
The material properties were measured for different types of limestone originally from different places around the world with the same equipment and under identical conditions. The decomposition temperature of the limestone was determined by means of a simultaneous thermogravimetrical and differential temperature analysis. Limestone and lime thermal diffusivity was measured with a laser flash apparatus and the specific heat capacity with a differential scanning calorimeter. The temperature range used was from room temperature up to 1300ºC. A high reproducibility of results was reached among the samples of limestone of every origin. The measured decomposition temperature in an atmosphere of CO2 at 105 Pa was found to be within the range between 908º and 920ºC depending on the structure of the stone. The specific heat capacity is influenced by the origin and shows a lower dependency on temperature as reported in literature. The diffusivity of lime is strongly influenced by the origin of the stone.
Keywords: Laser flash, lime, thermal diffusivity, limestone decomposition temperature, specific heat capacity.