Click the image to see a larger version of the same picture. High thermal efficiency is obtained because the heat from the thermal medium goes directly into the process mass. As the material comes into contact with the heated trough and agitators, the process mass is heated via conduction. With an insulated dryer, very little heat is lost. For most applications, no external sweep gas is required.
Exhaust gas is minimal and at a low temperature.
Therefore, the volume of non-condensable gas from the dryer, which might require treatment, is minimal. Minimal volume combined with the low temperature of the off-gases minimize the risk of spontaneous combustion. The K-S Paddle Dryer is an indirect heat transfer device which utilizes a high degree of mechanical agitation to enhance contact with the product being dried. A large heat transfer area to volume ratio is achieved by the use of hollow paddles and a jacketed vessel, through which the heating medium flows. Evaporation rates per square foot of heat transfer surface are maximized through self-cleaning paddles and the mixing effect.