The Science of UV Light

Ultraviolet light exists at the invisible, violet end of the light spectrum. Although we can't see UV light, we are exposed to a small amount every time we walk out into the sun.

How does UV work?

UV rays penetrate into bacteria and viruses and destroy their ability to function and reproduce. When a micro-organism is exposed to UV-C, the nuclei of the cells, due to photolytic processes, are so changed that cell division, and therefore reproduction is prevented.

The process is simple but effective: our systems destroy 99.99 per cent of harmful microorganisms without adding chemicals or changing your water's taste or odour.

Ultra-violet treatment is required to make water hygienically pure & safe. It mainly consists of a sterilization chamber in which powerful ultra-violet lamps of 254 nm wavelength are fitted centrally. The specific wavelengths responsible for this reaction are situated between 240 - 280 nanometers (referred to as nm) with a peak wavelength of 265 nm, and are known as UV-C,

These lamps gives a germicidal ultra-violet energy dose in excess of 30,000 micro watts sec per sq.cm. to water, which kills all harmful water borne micro- organisms like bacteria, yeasts, molds, algae etc., instantly..

1. Water enters the sterilizer and flows into the space between the quartz sleeve and the outside chamber wall

2. Within the chamber, water is exposed to intense germicidal ultraviolet radiation.

3. Transformer with plug.

4. Outlet of water is instantly ready for use

Advantages:

UV does not alter taste, odour, colour or pH of the water

UV does not require the addition of chemicals

UV does not impart toxic by-products into the water

UV systems are compact and easy to install

UV systems require very little maintenance

Running costs are often lower than those of a household lightbulb

Chlorine dioxide Disinfection

ClO2 is used principally as a primary disinfectant for surface waters with odor and taste problems. It is an effective biocide at concentrations as low as 0.1 ppm and over a wide pH range. ClO2 penetrates the bacterial cell wall and reacts with vital amino acids in the cytoplasm of the cell to kill the organisms. The by-product of this reaction is chlorite.

Chlorine dioxide disinfects according to the same principle as chlorine, however, as opposed to chlorine, chlorine dioxide has no harmful effects on human health.

Hypochlorite Disinfection

Sodium hypochlorite (NaOCl) is a compound that can be effectively used for water purification. It is used on a large scale for surface purification, bleaching, odor removal and water disinfection.

Hypochlorous acid is divided into hydrochloric acid (HCl) and oxygen (O). The oxygen atom is a very strong oxidant.

Sodium hypochlorite is effective against bacteria, viruses and fungi. Sodium hypochlorite disinfects the same way as chlorine does.

Advantages:

Sodium hypochlorite as a disinfectant has the following advantages:

» It can easily and be stored and transported when it is produced on-site.

» Dosage is simple.

» Transport and storage of sodium hypochlorite are safe.

» Sodium hypochlorite is as effective as chlorine gas for disinfection.

» Sodium hypochlorite produces residual disinfectant.

Disadvantages:

» Sodium hypochlorite is a dangerous and corrosive substance.

» While working with sodium hypochlorite, safety measures have to be taken to protect workers and the environment.

» Sodium hypochlorite should not come in contact with air, because that will cause it to disintegrate.

» Both sodium hypochlorite and chlorine do not deactivate Giardia sp. and Cryptosporidium