A single drum drier, operating at atmospheric pressure, is being used to dry a wet slurry, containing 2.0 kg water per kg dry solids, to a final moisture content of 0.1 kg water per kg dry solids. The drum is heated internally with saturated steam at 500 kN/m², has a diameter and width of 0.5 m. The load factor on the drum is 0.05 kg/m² of dry solids. The product is removed from the drum at a point 2/3 of the circumference from the feed point. Calculate the speed of rotation of the drum in r.p.m. and the rate at which dry product is produced in kg/h. The overall heat transfer coefficient for the complete drying cycle is 850 kJ/m² h °C.

A single drum drier, operating at atmospheric pressure, is being used to dry a wet slurry, containing 2.0 kg water per kg dry solids, to a final moisture content of 0.1 kg water per kg dry solids. The drum is heated internally with saturated steam at 500 kN/m², has a diameter and width of 0.5 m. The load factor on the drum is 0.05 kg/m² of dry solids. The product is removed from the drum at a point 2/3 of the circumference from the feed point. Calculate the speed of rotation of the drum in r.p.m. and the rate at which dry product is produced in kg/h. The overall heat transfer coefficient for the complete drying cycle is 850 kJ/m² h °C.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter6: Forced Convection Over Exterior Surfaces

Section: Chapter Questions

Problem 6.12P

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