Tray Oven

Tray dryer cabinet is a simple large steel or wooden box fitted with internal runners to support the trays of food being processed. The trays are loaded into the chamber, the doors closed and heated air is blown through the stack of trays until the entire product is dry. As the hot air enters below the bottom tray, this tray will dry first. The last tray to dry is the one at the top of the chamber. The advantages and disadvantages of this system are :
• Simple, low cost chamber
• low labor costs – simply load and then unload
• a tendency to over-dry the lower trays
• low efficiency, in terms of full consumption, in the later stages of drying when most of the trays are dry.

The dryers are made of trays held in a cabinet which is connected to a source of air heated by gas, diesel or bio-mass such as rice husk. The air temperature is usually controlled by a thermostat. The air enters the bottom of the chamber below the trays and then rises, through the trays of food being dried, and exits from an opening in the top of the chamber. In the Practical Action systems the trays are designed to force the air to follow a longer zigzag route which increases the air/food contact time and thus improve its efficiency. This system also reduces back pressure which means that cheaper, smaller fans can be used.

It has wide range of applications in food industry, agricultural industry, Pan Masala industry, Pharmaceutical industry and many more industry which require heating of their products.