The firing process is the core of the tiles production, currently the single-cycle firing is the most widespread method in ceramic industries. Moreover, the increasing demand of technological improvements and technical diversifications of ceramic products, leads the firing process to continuously adapt to new operative conditions. The physical mechanisms that occur in roller kilns have to be understood, mainly those involving thermal performance of the equipment and technical characteristics of the ceramic tiles. In this work, a mathematical model and an experimental procedure has been applied to determine the shrinkage kinetics. The kinetic parameters have been experimentally determined using industrial powder to obtain test pieces of 80 x 20 x 2.3 mm³ fired in laboratory electrical roller kiln. Activation energy, Ea=178 kJ/mol, parameter "n", n=0.26285 and frequency factor, k0=44768 s-1 were determined after several firing conditions 30, 40 and 50 min cold-to-cold and temperatures from 1000 to 1150 ºC (steps of 30 ºC).
firing; sintering; kinetic; ceramic tile
