An alternative form of water treatment is to use UV disinfection or Ultra-Violet light which either destroys microorganism on contact or stops their ability to reproduce. The optimum UV wavelength for UV disinfection is 264 nanometers within the UV-C spectrum. But a germicidal wavelength range between 200 and 300 nanometers is suitable in many instances.
What is a UV disinfection system?
A UV disinfection system utilises UV light in the germicidal wavelength range (254 nanometers) to disinfect water. The UV disinfection system combines a number of components to allow the UV-C light to penetrate the water stream.
A UV System comprises of the following
- UV lamps
- Quartz thimbles
- Reactor housing manufactured from 316SS
- Power supply
The reactor housing will contain one or multiple UV lamps which are installed within quartz thimbles within a reactor. Quartz thimbles houses the UV lamp and protects it from contacting water. The role of the quartz thimble is important because any water contacting the UV lamp will cause it to fail. A reactor will have an inlet and an outlet port positioned on opposite ends. Lamps are either installed through the centre, with water flow parallel to them or in some systems, the lamps are installed adjacent to the water flow.
How it works
When the UV light comes in contact with viruses, spores or bacteria breeding in your water supply they absorb the UV rays into their DNA rendering them incapable of reproduction or infection.
What is the effective dose to kill bacteria?
A UV dose of 40 mJ/cm² (400 J/m²) will give a 99.9% reduction in almost all human pathogens swimming around in your drinking water.
Are UV lamps dangerous?
UV Lamps need to be handled and operated with caution. UV lamps generate radiation that is harmful and human exposure should be vigorously prevented. Please read and comply with the manufacturers installation instructions at all times when installing or replacing UV systems and parts.
The Clean Water Co has selected the appropriate UV system providing a dose of 40 mJ/cm² for your whole of house water treatment system.