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UV-C in Professional Kitchens - Grease Elimination and Odor Control
Keeping the kitchen hood and exhaust system ducts clean and hygienic is crucial in restaurants, large kitchens, community kitchens, shopping malls, office buildings, hotels, and food courts. Proper hygiene prevents (and eliminates) devastating problems caused by inefficient ventilation systems while reducing the risk of fires. Besides this, the challenges associated with reducing the odors produced by cooking food are widespread and represent an increasing issue in all restaurants.
FOUL ODORS PRODUCED BY COOKING FOOD
The type and quantity of pollutants emitted depend mainly on the cooked product, the cooking methods, and the means used. The substances responsible for cooking odors are fatty acids, aliphatic and aromatic hydrocarbons, aromatic amines, and aldehydes. There are many ways to filter odors, but there are no specific rules for “olfactory pollution.”
Odor is a complex phenomenon to understand, not just for the wide range of potentially odorous substances, but mainly because the ability of a sense to be perceived by our olfactory system depends on different aspects that are both objective (volatility, water solubility, etc.) and subjective (physiological and psychological of the observer) but can also involve the environment (temperature, pressure, relative humidity of the air, speed and direction of the winds). This means that the same substance, at a distance from the source, is perceived differently by different people.
Organic compounds can constitute a vital friction point between the restaurant/hotel/catering and the surrounding environment since smells can spread over large areas. Without that, anybody can carry out resolutive interventions to contain it, avoiding the exasperation of the people involved.
GREASE AND THE RISK OF FIRE
According to the National Fire Protection Association (NFPA) in the USA, most restaurant fires originate on kitchen cooking appliances, flare into the kitchen exhaust system laden with grease, and then onto the building roof. Fat pollutants are also generated during food cooking, and grease layers will form inside the kitchen hood and the exhaust system ducts. So besides the inconveniences caused by unpleasant smells, fat deposits can pose a risk of fire risks. To prevent the formation of grease in the exhaust system ducts, continuous maintenance operations are necessary.
UV-C LAMPS TO PREVENT THE RISK OF FIRE AND ANNOYING SMELLS
UV-C lamps are unique lamps whose light emissions can break the bonds of fat compounds by “breaking” them down into simpler molecules already present in the air (such as H2O, CO2, etc.). This is scientifically called “cold combustion.”
So UV-C technology is the most effective way to reduce grease deposition on the ductwork and pollution in the exhaust system ducts. The advantages of using this technology extend far beyond their effectiveness and, among other things, allow you to:
- REDUCE THE RISK OF FIRE
- REDUCE COSTS for the maintenance of the kitchen hood and the exhaust system ducts
- REDUCE THE USE OF CHEMICALS FOR SCIENCE
- ENSURING SAFETY in the cooking area
- ENSURING CLEANING and hygiene of the cooking area
EFFECTIVENESS OF THE LIGHT PROGRESS “UV-SMELL” PRODUCT
Suppose it is challenging to test the effectiveness of reducing odors since they are perceived differently from person to person. In that case, it is, however, possible to carry out tests to verify the effectiveness of UV-C technology in reducing the formation of grease inside kitchen hoods and smoke evacuation systems. Light Progress Srl designed and manufactured a “UV-SMELL” section in Italy as part of our study. We ran an internal test on 12 different UV-C applications in professional kitchens. The test shows that in each of the 12 applications, the grease concentration inside the hood is significantly reduced if a UV-C section is placed inside the hood. The “UV-SMELL” systems can be installed in hoods that treat from 1,000 mc / h up to 4,800 mc / h of exhausted air and are, therefore, a flexible solution for various systems, both newly installed and existing.
COMBINE UV-C WITH OZONE, TITANIUM DIOXIDE, AND CARBON FILTERS FOR ADDITIONAL EFFICACY
The ideal ventilation system in a large professional kitchen should include a portion containing UV-C lamps, possibly with lights with Ozone emissions and filtration systems in Titanium Dioxide (TiO2) and Silver Salts to achieve higher efficiency. The first combination is with TIOX® honeycomb filters, an original Light Progress filter coated with nano-structured Titanium Dioxide (TiO2) and Silver Salts that, in combination with the very high UV-C power emitted by lamps, is an excellent photo-catalyst that degrades pollutants and organic and inorganic compounds (SOV, NOx, and VOC volatile organic compounds, nitrogen oxides). Consequently, the TIOX® filter performs further oxidation of polluting particles and contributes significantly to the deodorizing action of UV-C. Installation is straightforward and safe; the only precaution is to mount it downstream of mechanical filters that micronize fat molecules like standard mesh or labyrinth filters. A second option for maintaining cleanliness and eliminating odors is to use UV-C lamps that emit ozone. An oxidation reaction is triggered as soon as ozone comes into contact with molecules, which are oxidized and transformed into harmless molecules, thus eliminating any form of foul smell. Some lamps can be made with special transparent quartz at a wavelength of 180 nanometers, which can “transform” oxygen molecules into Ozone (O3).
The application in the kitchens’ ventilation channels effectively eliminates odors precisely because ozone can “follow” the smells along the ductwork, eliminating them before they are released outside. The properties of ozone are both ultra clean and persistent over time; ozone is, in fact, a volatile molecule that tends to re-transform into oxygen soon. Finally, applying UV-C technology, stand-alone or combined with Ozone emissions and Titanium Dioxide filters, perfectly combines with activated carbon filters. These technologies fight odors effectively together, and carbon filters are vastly improved by applying ultraviolet rays, increasing their durability and efficiency.
A SAFE TECHNOLOGY, SUITABLE FOR NEW APPLICATIONS AND RETROFIT APPLICATIONS
Installation of the technologies mentioned above is widespread in professional kitchens. Despite certain best practices and recommendations, their technologies are safe and easy to install. Installing UV systems right after the hood keeps surfaces clean from the start, and the air “free” of fat compounds leaves no residue in the ventilation duct. The optimum airspeed must not exceed 2.5 m / s. In the hood, UV systems must be positioned so that filters shield the rays from the operator and provide an easy way to turn them off. Using ozone, it is always advisable to add a pressure switch that automatically switches off the UV system in the event of a stop in ventilation. This is to guarantee operators’ safety.
In the case of outlets at street level and the application of UV + Ozone systems, it is essential to ensure that the ozone has completely “turned back” into oxygen before the air comes out into the street. Usually, a few meters of channel are required for this to happen. Otherwise, applying a second UV-ONLY system at the outlet can guarantee its complete elimination; UV-C rays “help” the O3 molecules turn into O2.