Tray dryer which contains a cabinet with a heater at the bottom. The values of these ovens are very low because of their uncontrollable heat transfer or humidity. When we fit a fan in the oven, the circulation of the forced hot air gets started. This process is beneficial for reducing the local flour concentrations and also for increasing heat transfer. In the direct circulation form, the air is heated and then focused on the object in a controlled flow. The material to be dried is dispersed on the tiers of the trays. For the circulation of the air across the drying materials, the screens in trays are perforated and lined with paper. A limited amount of heat is provided to every shelf at that time when the air passes over it to provide the latent heat of vaporization. This kind of dryer provides proper control of humidity and temperature.

The tray dryer can be electrically or steam heated. It consists of any number of trays that vary with customer requirements. It is fabricated out of a rigid angle iron frame with double-walled panels insulated with the best quality compressed fiberglass and with a rigid door fitted with strong hinges and the best-chosen locking system. There may be a facility to circulate hot air such as fans. A control panel is fixed in the front of the oven to facilitate easy operation. It has a large functional space and is made of mild steel and in good finishing outside with synthetic enamel color and inside painted with heat resistant paint to resist temperatures up to 300 ºC.