Marcheluzzo Ceramics in Asia
The expansion of Marcheluzzo Ceramics/IT in Asia continues with new air-conditioning, pre-drying and drying plants. More and more, in countries with high temperatures and high humidity levels the installation of systems able to evacuate internal humid air is required, guaranteeing greater people well-being and always controlled drying conditions. The daytime thermo-hygrometric conditions to be maintained in the casting room normally vary between 30–32 °C and 60–65 %.
However, with similar values outside and considering the production of internal water steam, the internal humidity reaches values that can exceed 90 %. This, together with an increase in temperature, can lead to extreme internal conditions that must be specifically managed to guarantee production and human well-being. The air-conditioning systems of the casting rooms are not so frequent in small- and medium-sized companies manufacturing ceramic sanitaryware: mistakenly, it is thought that, being high temperatures, it is not necessary to air-condition the rooms. But in this way, the relative humidity is not managed: relative humidity is the one that regulates drying of the pieces immediately after demoulding. The use of refrigeration units to reduce humidity in a ceramic production room is unthinkable due to extremely high electricity consumption. Other dehumidification systems, such as silica-gel rotaries, are not suitable due to high water quantities to be removed under high dust conditions.
Therefore, the casting rooms need a continuously injection of a certain amount of external air with an absolute humidity lower than the internal one. At the same time, the same quantity of air must be punctually extracted. The system must also guarantee the air homogeneity in order to avoid shaded areas or excessive flow speed over the pieces. If then the casting room is traditional, during the night the mold must be recovered and temperature rises up to 40 °C, but the relative humidity must be kept around 45 %.
In countries where temperatures are usually close to 30 °C, there are two systems that regulate thermo-hygrometric parameters: systems that control only humidity (ventilation), and systems with the possibility of temperature management (air handling units with heat generator). These systems also greatly improve the environmental conditions: lower humidity means better working conditions, while the filtration systems give a higher air purity degree. Normally, the pieces stay in the casting room for a longer or shorter period of time, precisely because the used dryer do not allow product loading before the contraction phase of the products completed.
Marcheluzzo Ceramics dryers are designed to perform both pre-drying and drying phases with the same machine. On the other hand, if this is not possible, the chamber pre-dryers are mostly recommanded: even in this case, the relative humidity control becomes fundamental, adjusting the pieces contraction homogeneously and controlled.