| 摘要 |
<p>APPARATUS AND METHOD FOR STEAM DRYING A method and apparatus are disclosed for drying materials by contact with a drying gas consisting essentially of internally generated superheated drying steam above 212.degree.F., to vaporize the water in the material and remove it to produce the steam used for drying. A minor portion of steam is removed from the drying gas and discarded to maintain pressure equilibrium. The drying steam is produced within the drying chamber from water evaporated from the material being dryed and is either heated to form the superheated steam within the drying zone where it is in contact with the material or removed from the drying zone, heated to form superheated steam, and returned to the drying zone for contact with the material during drying. A wood veneer dryer employping the invention is described as well as an apparatus for drying particulate material. The drying zones provided with the veneer dryer have at least along the major portions of their lengths a negative internal pressure which is below that of the ambient external atmosphere outside the dryer to prevent pollutants from leaking out of the dryer and ambient air is prevented from entering the dryer into such drying zones.</p> |
