INFORMATION FOR ENGINEERS DESIGNING UV WASTEWATER TREATMENT

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UV wastewater systems are designed for different peak flow rates.  The flow rate will dictate what options are available.  Typically, <100,000 gpd, 500,000 gpd, 1 mgd, 5 mgd and 10+ mgd can be used as a guide.

Open Channel Horizontal

Open Channel Vertical

Closed Chamber (aka vessel)

Tube System (non contact)

The UV transmission (UVT %), the amount of light that can pass through, is typically around 65%.  This number will vary based on the quality of the pre-treatment.  The lower the number, the more lamps are required.

A data collection sheet is included below as an attachment.  In addition to the design information, engineers need to understand parts cost, energy cost and typical service requirements.

UV wastewater systems are designed to operate in outdoor conditions.  It is recommended that shade structure or pole buildings be placed over the equipment for worker safety, system longevity and heat issues on the controls.   

Discharge permits vary based on the location.   For typical plants, UV systems are designed to meet a certain dosage.   Traditionally, 30 mJ is used and is calculated at end of lamp life with quartz fouling and is used for 126/100 ml E.coli or <200/100 ml for fecal coliform.