About the Practice
Problem Statement:

The perishable agriculture products was very difficult to preserved for longer duration by convectional method. By this innovation community can able to save lot of food products. The driers are simple in design, easy to operate, energy utilization is maximum. It’s cheap and affordable. By the usage of these driers granular materials can be dried e.g., coconut into copra, grapes into raising, chilies, stems of medicinal plants etc. Source: nif.og.in http://nif.org.in/innovation_improved_natural_convection_drier/111


Agriculture products which are perishable can be preserved for longer duration of time if it dried properly. To overcome the drawback of convectional driers, the innovator created a machine in which the hot the hot air is generated separately outside the drying chamber and is conveyed upward through a separate duct by natural convection. At the top of the duct an opening is provided for the entry of the hot air to the drying chamber, where perforated trays are arranged one above the other. Except for the bottom side all other sides of the drier chamber are covered with heat insulating materials. The hot air after entering the drying chamber tends to occupy the topmost layer just below the top covering sheet. As the hot air comes into contact with the wet material on the top tray, the temperature of the air drops, consequently, the density increases and has a tendency to flow down by percolating through the trays, where the wet material is placed. The cooler air, by the process of heat transfer, finally leaves the bottom of the drier to the atmosphere. Without the help of any blower or fan the hot air is made to flow in a downward direction after overcoming the frictional resistance offered by the perforated trays and the wet material contained in them gets dried. It comes in various models.

About the Innovator

Knowledge Provider / Innovator: P P Thomas
Address: Process Engineering Division, P.O: Industrial Estate,
City: Thiruvananthapuram
State: Kerala
PIN Code 695019

Practice Details

Link: RRLT-NC Drier Model no. 101: It is also called 'Domestic trays are provided in drying chamber. An electrical heater of 500/600 watts is provided water-evaporating capacity is 500gms per hour. A thermostat is also provided to control the temperature. RRLT-NC Drier model no. 151: It is called 'small farmer model'. Its capacity is double than model 101. An electrical heater of 1000 watts powers it. Here the heater and the duct housing the heater are placed at the center. RRLT-NC Drier model no. 201: This model is also called 'small farmer's model' with agricultural waste burning system. The capacity & construction is same as that of model 151. Hot air is generated by the burning of agricultural waste materials like coconut shell, husk etc. nif.org.in (http://nif.org.in/innovation_improved_natural_convection_drier/111)
Manufacturing Capacity: a) Turnkey solution, b) Design Support, c) Sub-contracting, d) Licensing, f) Any other:
Photo Links:

Problem Scale: 1) India 2) Around the world

GIAN Reference: GIAN/UAL/1226

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