Drum Dryer with Pipe Feed

FIG 8 - DOUBLE-DRUM DRYER WITH PIPE FEED... 

A typical drum dryer—a double-drum unit with center feed— is shown in Fig. 24.17. Liquid is fed from a trough or perforated pipe into a pool in the space above and between the two rolls. The pool is confined there by stationary end plates. Heat is transferred by conduction to the liquid, which is partly concentrated in the space between the rolls. Concentrated liquid issues from the bottom of the pond as a viscous layer covering the remainder of the drum surfaces. Substantially all the liquid is vaporized from the solid as the drums turn, leaving a thin layer of dry material that is scraped off by doctor blades into conveyors below. Vaporized moisture is collected and removed through a vapor head above the drums. 

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