Rotary Spray Humidifier
Air in HVAC systems is often humidified using rotary spray humidifiers. The excellent humidification effect is set against an increased microbial hygiene risk. This is why the German standard VDI 6022 “Hygienic requirements for ventilating and air conditioning systems and air handling units” details the requirements for the construction and operation of humidifiers. For example, in the hygiene parameters defined for circulating water the total colony number must not exceed 1,000 CFU/ml. To ensure this, regular hygiene checks that also include microbiological germ counts should be carried out. A problem is that even under good conditions germs can multiply in the circulating water – and therefore also in the air stream. Micro-organisms such as bacteria and moulds are distributed around the whole building via the HVAC system and present a risk to human health. This means that it is essential to prevent germination in the circulation water.
The Advanced Air hygiene water disinfection system achieves this aim. A pump directs the circulating water through a separate water circulation where it passes through a filter and the UV-C disinfection system. The separate circulation ensures that even when the HVAC system is not operating the disinfection of the water prevents dangerous germination of germs. This means that it is not necessary to empty the water during shutdown time. Longer intervals for microbiological checks are a further positive aspect. The same problem applies to the operation of re-cooling plants. When cooling water is sprayed it also enters the air flow. As the water also circulates here there is a great risk of germs germinating. The development of biofilms is reduced with the use of a circulating UV-C system. The standard UV-C dis-infection system is available for recirculation of 3 or 9 m³/h, corresponding to 1 or 3 m³ of water in a basin.
The germs are destroyed by means of UV radiation on a wavelength of 253.7 nm. This wavelength has a lethal effect on micro-organisms, such as bacteria, moulds and yeasts. Low-pressure UV-C emitters serve to generate short-wave UV-C radiation, which provides a high level of radiant efficiency. The UV-C emitters are monitored and con-trolled with a display that continuously measures the irradiance and immediately reports any faults via a potential-free output.
Advanced Air Hygiene supplies a completely pre-assembled installation kit which simply requires two pipes to be connected. The straightforward retrofitting to existing rotary spray humidifiers is a great advantage. The shut-off valves used allow quick cleaning of the system. Optimum hygiene is achieved with the combination of water disinfection and a downstream Advanced Air Hygiene air disinfection system. Challenge us and see what we can do for you!.
UV-C water disinfection system, circulation pump, filter, shut-off valves, pipework