The advanced treatment and reuse of wastewater is becoming increasingly common as municipalities address high water demands and shrinking supplies. Australia, Spain, Italy, California and Florida, to name a few, must balance increasing population growth, dry climates and heavy irrigation/agricultural demands.
Reusing wastewater is an essential strategy for wastewater treatment plants in these regions and UV disinfection is a key element in the treatment scheme. UV offers the benefits of not producing byproducts and replaces a complicated three step chemical disinfection process with a single physical UV process. When a chemical disinfection process is used, the reuse water must be chlorinated, dechlorinated and then aerated if required. For reuse water, high chlorine doses may be required which increases the likelihood of disinfection byproduct formation.
Most regions require UV systems to meet high dose requirements (in California it is known as Title 22) based on Ultraviolet Disinfection Guidelines for Drinking Water and Water Reuse published by the National Water Research Institute [NWRI] / American Water Works Association Research Foundation [AwwaRF].
The high water quality produced by upstream media or membrane filtration provides excellent pre-treatment to increase the UV system’s effectiveness. TrojanUV disinfection systems have been installed in reuse applications around the world. The treated effluents are being reused for recreational and agricultural irrigation, aquifer recharge and to reduce discharge to already-stressed waterways. In some applications like Indirect Potable Reuse, Trojan provides UV-oxidation systems for chemical contaminant treatment along with high-level disinfection.