Something to Snack on
French fries and chips are served hot, either soft or crispy, and appear on menus in restaurants, diners, pubs and bars around the world. The entire process of manufacturing frozen french fries is done by machines. Potatoes roll along conveyor belts and are sorted by size. Long, oval potatoes are designated for long, strip fries, while small, round potatoes are used for curly fries. Once separated, the potatoes are steamed and dropped onto another machine, where the skin is removed. From there, they make their way to another machine that cuts them into the appropriate shape and dips them in a dextrose sugar and sodium acid pyrophosphate to maintain their colour. The customer was using a commercial production line to make frozen french fries and other fried potato products. The original facility layout had all of the exhaust air from the frying hood ducted to a separate air treatment system. This system, located in a separate building, was comprised of a scrubber for solids capture and carbon for odour removal.
Just six months into operation, a reduction of airflow from the vent hood was noticed. Inspection of the ductwork revealed that oil and fat were collecting along the inside surface of a duct, creating, in some places, cake more than 2” thick. This build-up of oil is both a sanitary concern and serious fire hazard. For continued operation, a thorough cleaning of the ductwork was immediately required, followed by regular monitoring for recurring build-up. To properly fix the system, a better method of treating the air was necessary.
To minimise the amount of material drop-out in the ductwork, a RotoClone® W was installed indoors as close to the frying station as possible. This unit functions by injecting a fine mist of water directly into the air stream, followed by a rotating impeller. Any oils or particulates in the air are captured by the water and then separated. A centrifugal outlet adapter ensures that no water is carried over.
The elimination of oil and fat at the source has drastically reduced the need for routine cleaning of downstream duct work, resulting in both significant cost savings and increased machine availability. Because the RotoClone® W acts as an automatic fire barrier, it eliminated the need for sprinklers or suppression systems in the ductwork beyond the fan. Additionally, since water is continually added and removed from the unit, the potential for microbial growth or contamination is minimal.