LETS TAKE THE MYSTERY OUT OF UV DESIGN

Ultraviolet systems are being utilized for a growing number of wastewater disinfection application. Today we are seeing a transition from the early days of application when only low pressure UV lamps were employed in closed channel reactors to the current situation where a multitude of UV lamps are being proposed in open channel, closed channel, vertical and horizontal installations.. UV lamps are now available in low pressure, medium pressure and pulse configurations.The consulting engineering community is at the disadvantage of not having any formal University training pertaining to the application of ultraviolet to wastewater disinfection. The learning procedure is limited to the review of technical publications and sales propaganda from manufacturers of UV equipment. As a result, many false and misleading claims have been presented. Even the terminology has been tainted by marketing objectives. For example “ the low pressure low intensity “ UV lamp. There is no lamp manufacturer who produces a low pressure low intensity UV lamp. This is the label conjured by proponents of other types of lamps to imply a negative connotation to the standard UV source. Claims of “ magic” compounds that eliminate quartz coating, teflon tubes that do not foul, and lamps that last 3 times longer than any others have been suggested and sometimes accepted by the engineering community. The purpose of this paper is to take some of the mystery out of UV design, and to provide the consultant with the tools necessary to evaluate which UV system best meet the requirements of the client.There are a number of definitions that are critical to the proper understanding of ultraviolet disinfection:Ultraviolet DoseCollimated Beam TestUV Lamp LifeUV Lamp DescriptionUV Lamp Comparisons