Industry: Fruit and Vegetables (NAICS 3114) Dairy (NAICS 3115)
Process Brief: Water is removed using a vacuum to draw condensate and water vapor downward inside a tube that is heated by steam on the outside.
Energy source: Steam/natural gas
Falling film evaporators are the dominant technology in the food industry, representing an important advance over earlier rising film evaporators. The basic configuration is similar to a rising film unit, except that the liquid film moves downward in the tubes due to gravity. Creating a uniform film in the tube is difficult and is achieved by using specially designed nozzles or spray distributors at the top of the tube. The tubes are about 30 feet long and 1 – 2 inches in diameter. Process control is more expensive than rising film systems but the cost is justified by high throughput rates. Residence times are 20 – 30 seconds, compared to 3 – 4 minutes in a rising tube system. One concentrated orange juice facility installed a falling film evaporator with a capacity of 500,000 gallons per day. The evaporator had a capital cost of $2 million.
FMC photo and graphic from http://www.fmctechnologies.com/upload/tastearticle.pdf 3/2007;
Five-effect graphic from http://www.gea-wiegand.com/ndk_website/geawiegand/cmsdoc.nsf/WebDoc/ndkw5r8cu3 3/2007
FMC FoodTech Chicago
200 East Randolph
Chicago, IL 60601
Web site: www.fmctechnologies.com
GEA Wiegand GmbH
Telephone: + 49 (0)7243/705-0
Web site: www.gea-wiegand.com
9165 Rumsey Road
Columbia, MD 21045
Web site: www.niroinc.com
Swenson Technology, Inc.
26000 Whiting Way
Monee, IL 60449-8060 USA
Web site: www.swensontechnology.com