Sunflower and canola are most promising oilseed crops, because of high oil content, and these are attractive for the market trend towards products that help to reduce blood cholesterol levels. Autumn sunflower can be grown successfully in Pakistan, but after harvesting and threshing it is not easy to dry in sun because of cold weather. Therefore, appropriate drying equipment is needed to increase the production of autumn sunflower in Pakistan. Introduction
Sunflower and canola are most promising oilseed crops, because of high oil content, and these are attractive for the market trend towards products that help to reduce blood cholesterol levels. Autumn sunflower can be grown successfully in Pakistan, but after harvesting and threshing it is not easy to dry in sun because of cold weather. Therefore, appropriate drying equipment is needed to increase the production of autumn sunflower in Pakistan.
Technology Development, Development and Demonstration
Mobile flat-bed dryer was fabricated at Farm Machinery Institute, NARC, Islamabad. The dryer consists of a wheel adjustment assembly, a frame, a plenum chamber, a grain container, an engine, a diesel fired furnace, and an axial flow fan to force hot air through plenum to grain bed. The grain container holds the grain above the plenum chamber on a false floor through which the air is forced. A 65-cm diameter axial flow fan was used for forcing the drying air through grain bed. It is powered with a 5.7 kW diesel engine with V-belt and pulleys arrangements.
The mobile flat-bed dryer was preliminary field evaluated for drying sunflower in November and December, 2005 at Faisalabad. Experiments on sunflower indicated that the average drying temperature was about 58ºC. The dryer required about 3 hours to dry 1.25 tonnes of sunflower from about 30% moisture content down to a safe storage level of 10%. This shows that one may dry about 2.5 tonnes sunflower in one day (8 hours). The cost of drying sunflower is about Rs 1.25/kg with this machine. In future, this dryer will be field evaluated for drying, maize and groundnut.
Key Reference
Ahmad, M., and A. A. Mirani (submitted). Development and performance evaluation of a mobile flat-bed dryer for sunflower. International Agricultural Engineering Journal, USA.
