Affiliation:
1. College of Materials Science and Engineering, Chongqing University, Chongqing, China
Abstract
Apatite is the raw material, which is mainly used in phosphate fertilizer,
and part are used in yellow phosphorus, red phosphorus, and phosphoric acid
in the industry. With the decrease of the high grade phosphorite lump, the
agglomeration process is necessary for the phosphorite concentrate after
beneficiation process. The decomposition behavior and the phase
transformation are of vital importance for the agglomeration process of
phosphorite. In this study, the thermal kinetic analysis method was used to
study the kinetics of the decomposition of phosphorite concentrate. The
phosphorite concentrate was heated under various heating rate, and the phases
in the sample heated were examined by the X-ray diffraction method. It was
found that the main phases in the phosphorite are fluorapatiteCa5(PO4)3F,
quartz SiO2,and dolomite CaMg(CO3)2.The endothermic DSC peak corresponding to
the mass loss caused by the decomposition of dolomite covers from 600?C to
850?C. The activation energy of the decomposition of dolomite, which
increases with the increase in the extent of conversion, is about
71.6~123.6kJ/mol. The mechanism equation for the decomposition of dolomite
agrees with the Valensi equation and G-B equation.
Publisher
National Library of Serbia
Subject
General Chemical Engineering