Processing systems: Scraped surface heat exchangers
Scraped surface heat exchangers are used for processes likely to result
in the substantial deposition of suspended solids on the heat transfer
surface. In has been used for many years, and still are used, in
aseptic processing systems to heat and cool products.
In principle, a scraped surface heat exchanger is a monotube equipped
with a rotating internal scraper. The scraper keeps the heating surface
free from any deposits and also promotes turbulence.
Scraped surface heat exchangers can be employed in the continuous,
closed processing virtually any pumpable fluid involving cooking, slush
freezing, cooling, crystallizing, mixing, plasticizing, gelling,
polymerizing heating, aseptic processing, etc.
Use of a scraped surface heat exchanger prevents the accumulation of
significant buildup of solid deposits. Unlike tubes that usually operate
with water as medium, scrape surface heat exchangers tend to use steam
for greater heat transfer efficiency.
Due to the mechanical construction and the moving parts, scraped surface
heat exchangers are more expensive than any other heat exchanger use in
food processing. They can be justified only for heating/cooling fluid
foods that cannot be handled in normal tube or plate heat exchangers.
Processing systems: Scraped surface heat exchangers
