Air Blast Chiller/Freezer – Chilled Air
Industry: Fruit and Vegetables (NAICS 3114) Meat (NAICS 3116)
NAICS process:
311411 Frozen Fruit and Vegetables
311612 Meat Processed from Carcasses
Process Brief: Chilled air is blasted over the product to achieve rapid cooling
Energy source: Electricity/ some Natural Gas
Energy Intensity: 250-1,700 Btu/lb of product
Air blast chillers and freezers are the most used technology in the food industry. Air is cooled using mechanical (electricity) or thermal (natural gas) methods. An air blast unit blows chilled air at a speed of 5-20 feet per second, which achieves much higher heat transfer rates than still air units. Air blast equipment is very adaptable to a range of products and is critical for cooling recently slaughtered or cooked products before bacterial growth can spread.
Air blast technology is used in a variety of applications but chillers/freezers are common for the storage of fruits, vegetables, and meats. The heat transfer rate on the surface of the product is 2 to 5 times higher than still air technology because the high air velocity reduces the boundary layer of air around a product.
Energy Efficiency
From the CH Babb Company web site:
BABBCO High Velocity Air Impingement coolers are designed to assist in cooling baked products. They have replaced many existing nitrogen and refrigeration cooling systems providing our customers with significant cost savings. Each cooler is custom built to customer specifications so that the cooling needs of various products are accommodated. The units cool the product by distributing cooled air through a series of pressurized stainless steel distribution ducts positioned above and below the conveyor belt. The cooled air impinges upon the product and the belt through a hole pattern in the distribution duct that has a 75% open area for superior cooling capabilities. This cooled air is most often drawn from filtered ambient air through the use of a series of fans. If desired, a variety of options for cooling the air for more efficient cooling of the product is available including evaporation units, refrigeration, or chilled water. Depending on your products’ needs this cooling system can provide many advantages including a reduced workload for your existing spiral freezer.
More information at Cooling – Air Impingement
Manufacturers
C.H. Babb Company, Inc.
445 Paramount Drive
Raynham, MA 02767
Telephone: 508-977-0600
Web site: www.babbco.com
Source: Overview GRI-03/0075; photo from CH Babb web site 3/2007;