Akademik Veri Yönetim Sistemi
DRYING TECHNOLOGY, sa.March, ss.1-12, 2025 (SCI-Expanded)
Drying green ceramic tiles is necessary before the decoration and
sintering processes and constitutes an important input in terms of
energy consumption in the production step. Nowadays, natural gas-fueled
vertical dryers are used to dry green ceramic tiles. However,
alternative energy-efficient and environmentally friendly technologies
are being investigated and used in many drying applications, such as
microwave energy. In this study, the effects of magnetron power and
drying rate on moisture, surface temperature, and dried bending strength
of green ceramic tiles were experimentally examined. First, floor and
wall tiles with a wet-based moisture content of 6% were shaped with an
industrial hydraulic press with the specific pressures of 320 kg/cm2 and 300 kg/cm2
at the sizes of 33 × 33 cm and 25 × 40 cm, respectively. The shaped
green floor and wall tiles were dried separately with a horizontal
pilot-based microwave dryer at 20, 35, and 50 kW magnetron powers and
0.5, 1.0, 1.5, and 2.0 m/min belt speeds, and then the changes in
moisture, surface temperature, and bending strength values were
measured. The minimum and maximum 51 °C/143 °C and 50 °C/138 °C surface
temperature values were obtained for the floor and wall tiles,
respectively, after the microwave drying. The moisture values changed in
direct proportion to the magnetron power and inversely to the belt
speed. The moisture values were reduced from 6% to a minimum of 0.1%
under the conditions of 35, 50 kW of magnetron powers with 0.5 m/min of
belt speed for floor tile and 50 kW of magnetron power with 0.5 m/min of
belt speed for wall tile. In addition, the corner moisture values of
microwave-dried tiles were lower than those in the center on the
surface. The bending strength increased as the belt speed and magnetron
power decreased within the working conditions. The maximum bending
strength values for the floor and wall tiles were obtained as 29.2 kg/cm2 and 31.2 kg/cm2
at 20 kW magnetron power and 0.5 m/min belt speed, respectively. Of
52.4% and 42.6% energy savings in economic terms, 1000% and 837.5% increase in drying capacity, and 50.0% and 42.1% of environmental gain
were calculated for the drying of floor and wall tiles with microwave
energy compared to the natural gas, respectively. This study indicates
that microwave energy can be used as a more energy efficient and
capacity booster environmentally friendly process than natural
gas-fueled vertical dryers in green ceramic drying.