| 摘要 |
<p>A scraped surface heat exchanger is disclosed which includes a heat exchange cylinder (10) and a vertically disposed rotating drum (12) positioned within the cylinder having pivotal scraping elements (92) on the periphery thereof for scraping the cylinder interior surface. The cylinder and drum define an annular product flow chamber (16) through which product is pumped in heat transfer relationship to the cylinder. The heat transfer cylinder is surrounded by a thermally insulated jacket (14) which in combination with the cylinder (10) defines an annular flow chamber (32) for circulation of a heat transfer medium to facilitate cooling or heating of product passing through the product flow chamber (16). The drum (12) is mounted on a shaft (76) which is journalled in a bearing (110, 112) at only one end, requiring utilization of only a single seal (142) to seal the bearing (110, 112) from the product being heated or cooled. An indicator element (156) integral with a carrier (144) to which a rotating seal element (142) is attached, moves as the seal wears to provide a visual indication of seal wear. The carrier is designed such that the net product force acting on the carrier is in a direction tending to urge the relatively moving (142) and stationary (140) seal elements together. Rotary agitating elements (30) are preferably provided at the inlet to the annular product flow chamber (16) to distribute product, which is introduced at a single point, to the entirety of the inlet end (26) of the annular product flow chamber. A mixing chamber (70) located between the outlet end (20) of the annular product flow chamber (16) and the outlet (24a) of the heat exchanger, may be provided with co-operating stationary (78) and rotary (74) agitator elements to mix the product, thereby assuring uniform temperature distribution of product leaving the heat exchanger.</p> |
