Kenaf fibers are produced from the kenaf plant at a fiber yield of up to 25% by weight of the plant. Kenaf fibers have been used as industrial fibers in various industries such as inthe fiber board, paper, mattress and cushion, thermoplastic composites and animal feedmeal industries. Rotary drum and belt dryers with diesel fired flue gas drying mediumhave been conventionally used to dry kenaf fibers. However this drying medium tends toproduce discolored fiber. In addition the high cost of diesel may render the cost of kenafprocessing uneconomic. To overcome the discoloration problem, the present work usessuperheated steam to dry kenaf fiber. If excess steam is readily available in the kenaffactory than its use in the kenaf dryer reduces the drying cost further. The initial fibermoisture content is in the range of 2.0 to 3.0 dry basis. The drying experiments werecarried out at atmospheric pressure, temperatures in the range of 110 to 170°C and steamsuperficial velocity of 0.50 m s~(-1).The change in mass of kenaf fiber during the dryingprocess was periodically measured using an analytical balance connected directly to thewire mesh plate when the steam was diverted momentarily. The drying rate is faster athigher steam temperature. The drying rate initially increases to a maximum and then fallsoff exponentially thereafter. The drying kinetic data were fitted to Tan and Cenkowski'sand Hasibuan and Daud's models for steam drying. Tan and Cenkowski's model fits theexperimental data better with a lower mean residual squares than the Hasibuan andDaud's model. The superheated steam through drying system can successfully reduce themoisture content by almost 100 % in 15 minutes without steam condensation during thedrying process.
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