Ultraviolet
UV Disinfection of Water
UV light damages the DNA in bacteria, viruses, moulds and some protozoa, leaving them unable to perform cellular functions and multiply. UV is particularly highly effective against Cryptosporidium and Giardia – organisms resistant to chlorine that are a major risk to human health. UV-C rays penetrate microorganisms and destroy their ability to reproduce, effectively rendering them harmless.
It’s a simple but effective process, destroying a minimum of 99.99% of harmful microorganisms, including E. coli, Cryptosporidium, and Giardia. Not only is it safe and highly effective, but UV also does not change the taste, colour, or odour of water. It simply removes the risk of illness caused by microbial contamination, making water safe. UV light is generated by flowing electrons from an electrical source through ionised mercury vapour. Mercury is contained within a UV lamp and, for safety reasons, is isolated from exposure to water by the lamp envelope and the surrounding lamp sleeves.
The exact wavelengths emitted depend on the vacuum pressure within the lamp tube itself. Low-pressure (LP) UV lamps are evacuated to relatively ‘low’ pressures (between 1-10 Pa) and emit UV-C light at a single wavelength of approximately 254nm. Medium pressure (MP) lamps are evacuated at a ‘medium’ pressure and emit a broader spectrum of UV light, with higher intensities between around 254 – 265nm.
Low-pressure and so-called ‘Amalgam’ lamps are twice as efficient at converting electrical energy into UV-C light compared to medium-pressure lamps. However, medium-pressure lamps emit far more UV-C energy per unit length over a wider wavelength than low-pressure or amalgam lamps. Various considerations, therefore, need to be taken into account when choosing which of these lamps is suitable for a given application.
We offer a variety of UV disinfection systems including low and medium-pressure UV Disinfection Units. Our budget UV disinfection is ideally suited for residential RO purifications systems or whole-house filtration systems including rainwater filtration.
The Sterilight® Platinum™ “SP” series feature UV intensity monitoring and flow pacing for optimised operating efficiency. They cover a range of flow rates up to 220 litres per minute depending on the specific dose required. Our Sterilight SPV systems have undergone validation with NSF and hold certification to deliver an accepted dose of 40mJ/cm2. UV-C rays. Applications include private bores, camping grounds, hotels, boats, bottlers, aquaculture, hospitals, food, cottages, restaurants, breweries, water systems, laboratories, marine, pharmaceutical, dairies and many other applications requiring UV-monitored disinfection. A total of eight systems are available and cover point-of-use or high‐flow point-of-entry applications.