| 摘要 |
Apparatus and process for the removal of moisture from cellulosic products such as pulp, paper and molded articles, and textile products, wherein gaseous water (steam) in a superheated state is utilized in an energy efficient manner as the drying medium. The apparatus is an enclosed system that operates continuously to dry the products while preventing air contamination from entering the apparatus and thereby reducing its drying efficiency. The apparatus comprises a plurality of drying sections wherein the number of drying sectio ns connected in series is a function of the type and volume of the product or products to be dried. Within each drying section there exists indirect steam heating means, steam-recirculation means, an individual steam-supply chamber , and sections of a steam-return chamber which is open and common to all dryin g sections in the series. Air/vapor lock chambers at both ends of the apparatu s prevent air incursion into the drying sections and at the same time permit a slight amount of excess steam from within the drying sections to vent out of the apparatus. Steam-condensing means located substantially entirely within the drying sections of the apparatus is utilized to recover a large percentage o f the energy of the heat of vaporization. The process described herein involves conveying the products into the apparatus and directing the drying steam fro m the steam-supply chamber onto the products and drawing the spent steam away from the products. The spent steam, which comprises the drying steam in combinati on with the steam formed by the liberation of moisture from the products, is partially recirculated past the indirect heating means and back into the steam-supply chamber, and partially condensed by the internal steam-condensing means. The velocity at which the drying steam is directed onto the products can be vari ed in accordance with the type of product to be dried.
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