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Accessibility to fresh clean water has determined the location and survival of civilizations
throughout the ages [1]. The tangible economic value of water is demonstrated by industry's need
for water in fields such as semiconductor, food and pharmaceutical manufacturing. Economic
stability for all sectors of industry depends on access to reliable volumes of good quality water. As
can be seen on television a nation's economy is seriously affected by water shortages through
drought or mismanagement and as such those water resources must therefore be managed both for
the public interest and the economic future. For over 50 years ultraviolet water purification has been
the mainstay technology for water treatment, killing potential microbiological agents in water for
leisure activities such as swimming pools to large scale waste water treatment facilities where the
UV light photo-oxidizes various pollutants and contaminants. Well tailored to the task, UV provides
a cost effective way to reduce the use of chemicals in sanitization and anti-biological applications.
Predominantly based on low pressure Hg UV discharge lamps, the system is plagued with lifetime
issues (~1 year normal operation), the last ten years has shown that the technology continues to
advance and larger scale systems are turning to more advanced lamp designs and evaluating solidstate
UV light sources and more powerful laser sources. One of the issues facing the treatment of
water with UV lasers is an appropriate means of delivering laser light efficiently over larger volumes
or cross sections of water. This paper examines the potential advantages of laser beam shaping
components made from isostatically micro molding microstructured PTFE materials for integration
into large scale water purification and sterilization systems, for both lamps and laser sources.
Applying a unique patented fabrication method engineers can form micro and macro scale
diffractive, holographic and faceted reflective structures into fused and semi-fused PTFE materials
and compounds for use in UV Reactors. The materials unique attributes provide an unusual but effective hybrid element, by combining Lambertian diffusion and spectral reflective attributes. This paper will provide examples of the applications where this technology could be applied and typical constructions. An overview of UV sources commonly used in water treatment, including high power UV lasers and solid state UV light sources will be discussed. The paper will summarize how beam shaping elements produced in PTFE materials would provide further benefits to the emerging water disinfection or treatment market.
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