The Regional Municipality of Peel is located in Southwestern Ontario, Canada and is the second largest Canadian municipality after the city of Toronto.
The Peel Region draws its drinking water from Lake Ontario which is the smallest of the five Great Lakes. To meet the projected population increase to an estimated 1,571,000 people in 2031, the Region decided to upgrade and expand its Lorne Park Water Treatment Plant (originally built in 1975).
Unlike many water treatment plants in Ontario, the Lorne Park WTP, utilizes two separate treatment trains: conventional (120 MLD) and membrane filtration (380 MLD). Ultraviolet light in combination with hydrogen peroxide (UV advanced oxidation process) will be utilized on the membrane treatment train while UV alone will be employed on the conventional treatment train. The treated water from both trains is then blended before being distributed to customers. To deal with seasonal taste and odor (T&O) compounds produced by algae blooms in Lake Ontario, the membrane filtration plant is equipped with a TrojanUV advanced oxidation system. Combining membrane filtration and the UV advanced oxidation process (UV AOP) ensures that the residents of Peel receive the purest, most aesthetically-pleasing water possible.
The TrojanUV Solution
Trojan was selected to supply UV technology for both treatment trains at the Lorne Park Water Treatment Plant. For the membrane treatment train, the TrojanUVSwift™ECT UV AOP system was selected over other technologies (including ozone) to provide T&O treatment because the UV-oxidation system offered flexible operation, guaranteed performance, and required a very small footprint. Footprint was important, as the Lorne Park facility is built almost entirely underground.
The TrojanUVSwiftECT provides an additional barrier to microorganisms such as Cryptosporidium and Giardia, while destroying the algae-derived compounds 2-methylisoborneol (MIB) and geosmin. MIB and geosmin are responsible for periodic earthy/ musty taste in the finished water. These compounds are small enough in molecular weight to pass through most membranes. The treatment train at the membrane plant is as follows: Membrane filtration, advanced oxidation, and granular activated carbon contactors. The system is designed to meet and exceed current and future Ontario Drinking Water Quality Standards.
UV-oxidation System Design Parameters
|Peak Flow For Disinfection||390 MLD|
|83% (0.77 log) Reduction of Geosmin|
|Design Flow Rate For UV-oxidation||200 MLD|
|1.25 log Reduction Geosmin|
|1 log Reduction MlB|
|15 mJ/cm2 minimum dose (1.7 log reduction of Giardia)|