Medium pressure UV lamps effective from -5C to +70

Edited by the Processingtalk editorial team Oct 28, 2003

The bersonInLine range of powerful ultraviolet disinfection systems use specially designed medium pressure lamps which remain effective across a wide temperature range for drinking water treatment

The bersonInLine range of powerful ultraviolet (UV) disinfection systems use specially designed medium pressure lamps which remain effective across a wide temperature range.

This means they are particularly suitable for low temperature applications such as drinking water treatment.

Called bersonMultiWave lamps, they emit UV across a wide spectrum of wavelengths.

They have a higher surface temperature than low pressure UV lamps, but an isolation layer between the lamp surface and the protecting quartz sleeve prevents heat from transferring to the water passing through the treatment chamber.

Because of their high surface temperatures, bersonMultiWave lamps are unaffected by the temperature of the water being treated, remaining stable regardless of whether the liquid is as low as -5C or as high as 70C.

A number of users of low pressure lamp technology have reported reduced lamp life and/or reduced UV output due to cold water.

Research has shown that the efficiency of low pressure UV lamps, regardless of the manufacturer, falls significantly and becomes highly unpredictable at low temperatures.

Recent data even suggests that UV output can fall to zero when the incoming water temperature is below 5C.

Medium pressure lamps, like the bersonMultiWave, are unaffected at these low temperatures.

They have been used to treat drinking water and seawater - often at very low temperatures - for decades.

They always start up very easily, show no change in UV output, and do not age any quicker than lamps used to treat warmer liquids.

Many water works experience cold incoming water temperatures at various times of the year, or even over a 24 hour period.

Because medium pressure UV lamps are just as efficient during cold spells as they are during warmer periods, it is understandable that most operators now opt for this technology if there is any chance of low temperatures being experienced.