What is Ultraviolet Disinfection?

Ultraviolet light is invisible, electromagnetic energy with wavelengths between visible light and x-rays.  UV light has long been acknowledged as a means of disinfection because of its ability to kill bacteria by penetrating their outer membrane and impairing proper DNA function. Wastewater disinfection with ultraviolet light is a process that has proven to be superior to other disinfection methods. Many micro-organisms are not easily inactivated by chlorine or ozone whereas relatively low UV will provide the level of disinfection required. Operation and maintenance is less costly and less time consuming with UV systems, as compared to other disinfection methods. UV eliminates storage, handling and transportation hazards associated with chemicals and gasses. Through the use of UV: chlorine, its byproducts, and the need for dechlorination is eliminated. When UV light is harnessed and properly transmitted, it provides a practical, safe and inexpensive means of water disinfection. This is achieved through the use of low pressure mercury vapor lamps generate UV radiation in wavelengths as 2537A capable of destroying virtually all known forms of microorganisms and viruses.

How Does It Work?

Ultraviolet is that band of light located in the spectrum between 2000-3000 (Angstrom) wavelength.   The most effective germicidal range is at 2537A for destroying microorganisms, molds, spores, protozoa, virus and yeast. The intensity of ultraviolet is expressed in micro-watt seconds per square centimeter and is the product of the lamp output in watts, the length of time exposure and volume of water being treated microorganisms are destroyed with under 10,000 MW Sec./cm2.

Typical Example
Bacillus Anthracis	8700
Cholera	6500
Dysentery	4000
Infectious Hepatitis	8000
Typhoid Fever	4100
E Coli	7000
Legionella	7000
Pseudomonas	10500
Streptococcus	10000

 

Types of UV Units
Horizontal
Vertical
Self-Cleaning