Killing phatogens with light
This type of water purification uses UV rays to handle the harmful pathogens in the water. The UV rays don’t usually kill the organisms, but stops them from multiplying. This is one of the most effective water purification techniques.
UV light types
There are 3 types of UV light. Long-wave UV light has the lowest germicidal value. Middle-wave UV light is similar to the sunlight and it is know for its tanning effect and also has a higher germicidal action. Short-wave light is usually used in water purification. It destroys almost any micro organisms – bacteria, fungi, molds, spores and viruses.
For the short-wave UV light you will need a special mercury vapor lamp to convert electricity in light. Short-wave UV light doesn’t reaches the Earth because of the atmosphere.
The mercury lamp is also known as a germicidal lamp. It’s the most energy effective source of short-wave UV light. They are made from quartz glass and emit radiations that can kill organisms.
The mercury inside the lamp needs to be vaporized using an electric arc. This way the mercury becomes ionized and thus giving off the short-wave UV radiation.
There is one condition that needs to be fulfilled when using UV light – the water needs to be clear enough so that the light can penetrate.
The main advantage is that there aren’t any chemicals used within the purification process. Also this system doesn’t damage the pipes. The prices are more than affordable.
You will need to pre-filter the water before you use this purification technique, as it has to be clear. It also needs a constant supply of electricity.
You will need to replace the lamp once a year to assure maximum efficiency.