Multi-surface heat exchange with vacuum capability and magnetic scrapers

Abstract

A multi-surface scraped surface heat exchanger for heating or cooling of liquids or slurries having a series of three or more concentric tubes that provide four or more heat transfer surfaces, three of which are independently temperature and flow controllable. Slurry products are cooled or heated across all of the surfaces in line or in parallel. Scrapers are mounted on a rotor assembly and are magnetically or spring tensioned to increase surface engagement and may be contoured to enhance folding and mixing of product.

1 - 28 . (canceled) 
     
     
         29 . A multi-surface scraped heat exchanger, comprising:
 a heat exchange vessel having a base, a lid, and at least two cylindrical heat exchange surfaces with which food comes into contact during processing;   a rotor assembly motor;   a rotor assembly mounted in said heat exchange vessel and operatively coupled to said rotor assembly motor, said rotor assembly including scraper mounting apparatus;   a plurality of scrapers mounted on said scraper mounting apparatus so as to allow pivotal movement of said scrapers, each of said scrapers having a blade portion that engages a heat exchange surface of said heat exchange vessel; and   tensioning apparatus to urge said blade portion of said at least one scraper toward said heat exchange surface.   
     
     
         30 . The heat exchanger of claim  22 , wherein said heat exchanger vessel includes a cylindrical outer jacket section having one heat exchange surface, a cylindrical middle jacket section coaxially disposed within said outer jacket section and having two heat exchange surfaces, and a cylindrical inner jacket section coaxially disposed within said middle jacket section and having one heat exchange surface, said jacket sections defining an inner processing zone between said inner jacket section and said middle jacket section, and an outer processing zone between said middle jacket section and said outer jacket section. 
     
     
         31 . The heat exchanger of claim  23 , wherein each of said jacket sections includes a floor disposed on a lower end, a heat exchange fluid inlet and a heat exchange fluid outlet disposed in said floor, a partition dividing said jacket section into inner and outer fluid flow sections, and a cap disposed on an upper end, wherein said partition is spaced apart from said cap so as to function as a weir for fluid flowing from one of said inner or outer fluid flow sections to the other of said fluid flow sections. 
     
     
         32 . The heat exchanger of claim  23 , wherein said middle jacket section is a weir over which product flows from said inner processing zone to said outer processing zone. 
     
     
         33 . The heat exchanger system of claim  25 , wherein at least one of said outer, middle, and inner jacket sections are removably attached to said vessel base. 
     
     
         34 . The heat exchanger system of claim  25 , wherein at least one of said outer, middle, and inner jacket sections are removably attached to said vessel base. 
     
     
         35 . The heat exchanger of claim  25 , wherein at least one of said outer jacket section, middle jacket section, and inner jacket section, has a heat exchange fluid supply that is independent of a heat exchange fluid supply for one or more of the other of said jacket sections, such that at least one jacket section is independently temperature controlled in relation to the other of said jacket sections.