| 摘要 |
<p>The drum is heated externally, and its inner surface is provided with numerous hollow or solid bolts (I), aligned radially and possessing a round or elliptical cross-section. Bolts (I) are pref. 20-70mm dia., and have a length slightly greater than the height of the bed of material flowing through the drum. From ten to thirty bolts are pref. used per sq. metre of the internal surface of drum; and other bolts (II) are pref. located on the external surface of drum (I) to improve heat transfer to the material being dried. Used e.g. for drying carbon black or similar materials, where bolts (II) improve heating of the material being dried, so the productivity of the drum is increased.</p> |
