Calcination of Small-Grained Limestone in Fluidized Bed of Inert Granular Material. Part 1. Mathematical Description of Limestone Particle Calcinations Process

Abstract

A detailed mathematical description of the endothermic process calcination of limestone particles is presented while they are passing high temperature zone of fluidized bed inert particles. When constructing a mathematical model of thermochemical conversion of limestone particles, are made the following key assumptions: large-grained inert particles are in the mode ideal mixing, they are acting as a thermostat, and limestone particles are removed from the fluidization bed with the heating gas in the mode piston flow; calcium oxide particles formed as a result of thermochemical processing, retain the original amount of limestone particles with a corresponding change in the current volumetric particle porosity; pressure and density of the carbon dioxide produced in the calcination process on the surface of unreacted CaCO3 and which are determining the reaction rate of calcination are equal to the value of these parameters in the radial pores of particles; particle heating is provided only due to the thermal conductivity of the solid phase and by intensity of heat exchange «limestone particles — inert particles of fluidized bed». Bibl. 7.