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CHARCOAL STOVE

 

DESCRIPTION: This fuel-saving stove is cheap as well as durable, apart from being simple in design and convenient in use.

CONSTRUCTION: This stove consists of a clay cylinder with a narrow waist and a 50 cm square side opening at the base. It rests on a clay pan and a removable convex clay grate is positioned inside the clay cylinder, 12 cm below the top. About 300-500 of charcoal is placed within the upper section of the stove and lighted. The ignition time is 15-20 minutes with hardwood charcoal. There is no provision for heat regulation and no method of extinguishing before the full charge has burnt out.

The stove is made from clay, normally used in the manufacture of earthenware cooking utensils and roofing tiles, modified slightly by the addition of fine sand. Rural pottery centres can manufacture the stove by using a pottery wheel. Moulds are not vital, they certainly improve dimensional accuracy.

WORKING: The stove consumes charcoal at the rate of 250 gms per hour with a heating efficiency of 30%. A full meal for five adults is cooked in approximately two hours with a charcoal consumption of 490 gms. Three 1 cm thick ridges, equidistant from each other, traverse from the upper rim to the inside of the stove till a depth of 6 cm. Small vessels fit snugly inside the stove and larger vessels simply rest on the rim, but in all cases, the ridges provide the space required for the escape of exhaust gases.

The grate, (concave-shaped to raise the charcoal bed towards the vessel) has holes in 20% of the grate area, totaling 31 cm. square. The limited air supply through the grate controls the rate of burning which is approximately 250 gms per hour.

SOURCE:
Dhammika De Silva, Division of Wood and Cellulose Technology, Ceylon Institute of Scientific and Industrial Research, P.O. Box 787, Colombo 7, Sri Lanka
 

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