Anagi tray dryer
Practical Action
Operation
The furnace is filled with sawdust (about 30 Kg.). It is well compacted leaving a cylindrical
opening at the centre (vertical) extending it horizontally at the bottom. This is done by
inserting two GI pipes of 75mm diameter before packing with sawdust. Once the packing is
complete the two GI pipes are pulled out carefully creating two tunnel-shaped openings.
The furnace is ignited by a piece of coconut husk or a piece of wood dipped in kerosene oil,
inserted through the bottom opening.
Before firing, the lid of the furnace is closed and connected to the heat exchanger pipes. The
furnace can supply heat to the dryer for about 6-8 hrs.
There are 6 trays in the dryer. Once the trays are in position, the door of the dryer is closed.
2 ½ - 3 hours after the initial loading the bottom-most tray is removed and a new one is
loaded at the top. After which this procedure is repeated every half and hour.
The temperature must be kept below 800C for cashew. Adjusting the ventilation of the hearth
can control the temperature.
Excessive heating inside the drier can be eliminated by controlling the airflow by using the
flappers located above the heat exchanger coils. These flappers can be used to maintain a
constant heat supply throughout the tray.
The door of the dryer, has two flaps; one flap at the top to insert trays and another at the bottom
to remove the trays.
The lifting mechanism allows the removal of the lowermost tray when the cashew is dry. After
the tray has been removed, the rest of the trays can be lowered and a new tray can be added at
the top.
Maintenance
The dryer needs to be cleaned daily
The heat exchanger pipes need to be cleaned daily to avoid corrosion.
The pipes and tubes need to be checked and replaced in 6 - 12 months.
Cost
At present (2000) local fabrication costs is estimated between Rs 26,000 – Rs 28,000
(US$ 380)
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