HRS Process Technology Inc., a heat transfer specialist for the process industries in Glendale, Ariz., has supplied a U.S. manufacturer of processed meat and poultry ingredients with a Unicus hygienic scraped-surface heat exchanger for an expansion of the company's concentrated chicken broth plant.

The unit is used to sterilize up to 10 gal/min of concentrated chicken broth by heating it to 270°F (132°C) with superheated steam at 305°F (150°C). Because the broth contains 32 percent solids with significant protein content, heating to 270°F (132°C) presented an fouling problem for conventional heat exchangers. In such exchangers, a layer of burned-on product would rapidly build on the tube wall, requiring frequent cleaning, according to HRS.

The Unicus design includes hydraulically activated scraper elements inside the inner tube of a shell-and-tube heat exchanger. The elements continuously clean the tube surface to maintain good thermal transfer. Also, the reciprocating action of the scraper elements introduces turbulence, increasing thermal transfer efficiency.

The scraped-surface design allows the process to run for very long periods without downtime. Also, because the reciprocating action is slow and the product tends to lubricate it, wear and resulting consumption of spare parts is minimal, HRS says. For more information about HRS, go to