cost-effective municipal wastewater UV Disinfection treatment
 

UV Disinfection for Wastewater

Many municipal wastewater utilities have adopted ultraviolet (UV) disinfection treatment over chemical chlorine disinfection, as UV is an effective, safe, environmentally-friendly and cost-effective.

About UV Disinfection

UV disinfection is a physical process that instantaneously neutralizes microorganisms as they pass by ultraviolet lamps submerged in the effluent. The process adds nothing to the water but UV light, and therefore, has no impact on the chemical composition or the dissolved oxygen content of the water.

Application

1. Food processing and industrial water disinfection
 
2. Hospitals, various laboratory water disinfection, and high levels of pathogenic water disinfection
 
3. Municipal water
 
4. Biochemical pharmaceutical, cosmetics production water disinfection
 
5. Aquatic products processing water disinfection
 
6. Swimming pool water disinfection
 
7. Seawater, freshwater aquaculture breeding water disinfection
 
8. Ultra-pure water for electronic industry, and so on
 





Principle of Operation

UV sterilizers utilize germicidal ultraviolet lamps that produce short wave radiation lethal to bacteria, viruses and other microorganisms present in water.<o:p>
Ultraviolet water treatment purification is a unique and rapid method of water disinfection without the use of heat or chemicals.<o:p>
Through the years ultraviolet technology has become well established as a method of choice for effective and economical water disinfection.<o:p>




Technical parameters:
As a general guideline, the following are some typical UV transmission rates (UVT)
City water supplies850-980‰
De-ionized or Reverse Osmosis water950-980‰
Surface waters(lakes, rivers, etc)700-900‰
Ground water(wells)900-950‰
Other liquids10-990‰

Frequently asked questions about ultra violet lamps sterilizer
What is ultraviolet (UV) light?
UV light is part of the electromagnetic spectrum, shining at a specific wavelength. All light is given off at different wavelengths. For example if you see a rainbow, you will notice that the colours are always in a specific order from red all the way to blue. You are able to see each colour due to their individual wavelength. These wavelengths are part of the visible portion of the electromagnetic spectrum. 

UV light is at a wavelength of 254nm (nanometers), and is not visible to the naked eye. This portion of the electromagnetic spectrum is termed UV-C light or a germicidal wavelength. At this 254nm microorganisms undergo a genetic alteration which ultimately results in inactivation. Below is a representation of the electrospectrum: 

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. The water treatment industry uses special lamps that emit UV light of a particular wavelength in order to disinfect water.

How does UV work?
UV does not kill micro organisms like chlorine does, but instead UV inactivates them. UV light at a specific wavelength of 254 nm is readily absorbed by the genetic material of micro organisms. The DNA strand is coded with a specific sequence of something called base pairs. The sequence of these base pairs codes for certain characteristics. UV light at 254 nm is readily absorbed at the point on the microorganism's DNA strand which codes for reproduction. A microorganism that cannot reproduce, cannot make colonies and therefore cannot infect when consumed. 

Why not use chlorine?
Many people object to the taste and smell of chlorinated water. But more importantly, chlorine reacts with certain compounds that may be present in the water supply, resulting in by-products that have been linked to cancer (such as trihalomethanes, or THM's). UV light does not produce harmful chemicals in drinking water. It's safe, effective and environmentally friendly. 

Is pre-treatment of my water required for a UV system to work? 
Yes normally two filters are required a 1 & 20 micron filter. They should be installed upstream of any UV system so as to eliminate any particles large enough to block the UV light. The UV system should always be installed downstream of any other water treatment equipment. Ultimately, the quality of your water will determine if additional pre-treatment is required.