FAQs for UV Systems

UV Systems from Evoqua are a proven solution for disinfection and removal of organic and inorganic contaminants

Why UV?

UV light works by causing permanent damage to the DNA found in all living species. Once the DNA becomes damaged, or dimerized, the organism is unable to carry out the routine cell functions of respiration, the assimilation of food, and replication. Once the cell is rendered non-viable the organism quickly dies.

Why closed vessel UV?

The majority of UV applications are now performed in a closed vessel. In pipe systems, offer significant operator benefit, smaller footprint, faster installation, and reduce lifetime cost. Isn’t it time to stop accepting how it’s always been done, and start asking why not put it in a pipe?

In regards to UV, what is the difference between medium and low pressure UV?

There are three main differences: lamp power, electrical efficiency, and the type of UV light produced. Each lamp type is best suited for different applications, which our water treatment experts will be pleased to explain to you.

What is UV dose and how is it determined?

UV dose is calculated from the flowrate, the water transmittance and the lamp power. The dimension of UV dose is m J cm-2. We uses advanced Computational Fluid Dynamics (CFD) to accurately predict the UV dose that the water will receive, and then systems are validated by a third party test house to verify the predicted UV dose closely matches the actual delivered UV dose.

What is UV transmittance and how does it influence equipment selection?

UV transmittance (UVT) is a measurement to determine how much UV light passes through a sample of water compared to distilled water. Dissolved organics, suspended matter, color, and certain UV light absorbing metals are the main absorbers of UV light. It is the key factor in properly sizing a UV system to operate effectively.