Fluoropolymer tubes (Teflon, FEP) are extruded from a high purity resin into long tubes. FEP has optical properties that allow UV light to penetrate. teflon uv noncon
Some of the first wastewater systems in the 1980s were Teflon style. The EPA called it non-contact and it was the second most installed style behind closed (chambered) vessels.
Larger plants wanted to use the technology, but the chambers and Teflon systems could not scale up and because 40 lamps were required to treat 1 MGD, open channels became the standard. teflon uv noncon
FEP technology and its clarity have greatly improved, which allowed for the return of this style. These enhancements along with better lamp technology has made this a choice for many installations.
The primary benefit is low maintenance. Since the UV lamps are in the air (not in quartz sleeves submerged in the effluent) and the wastewater is contained within the FEP tubes, you do not have to remove the modules for cleaning.
The tubes do not foul because they are non-stick and do not carry an electrical charge. Traditional horizontal systems use quartz sleeves that carry a charge and this causes "plating" and "staining" and necessitates a cleaning regime. Algae and other solids are flushed through the tubes and this allows for tube cleaning.
teflon uv noncon
Change the lamps every 12,000 hours. Clean the tubes with the "bottle brush" when needed. noncon is scuva
1 minute visual overview of a tube system. Water contained in tubes and light is in air. teflon uv noncon