OZONE is increasingly used to purify water as an alternative to chlorination in three principle applications -- production of drinking water; sterilisation of swimming pools; and sterilisation of waste water after treatment and before release into the water cycle.
Lear Siegler says chlorination has fallen out of favour as the main purification method due to the significant health risks involved in transporting and handling chlorine.
Because of this, implementation ozone sterilisers have gathered pace in recent years. Both chlorination and ozonation have the same basic effect, and are extremely powerful oxidising agents; however after doing its job attacking impurities ozone breaks down to oxygen, which is totally harmless.
Why is moisture critical? There are three main reasons for measuring the moisture content of the feed air or oxygen to an ozone generator plant:
* Preventing arcing in the generator electrodes, which will lead to damage to the electrodes and system walls, and eventually to failure of the ozone generator.
* Preventing corrosion of system components due to nitric acid formation, a by-product of arcing, which will lead to the eventual failure of the ozone generator.
* Increasing ozonation efficiency, because the drier the feed gas, the more efficient the ozone generator. For example, drying the gas by an extra 2M dew point m improves efficiency by as much as 20%.
Michell Instruments, represented by Lear Siegler , has developed hygrometers that can be used to monitor the moisture content of the feed gas either on-line (Easidew Transmitter or Easidew On-line, Transmet, Cermet H) or on a spot-cheek basis (Easidew Portable or Cermax).
In conjunction with a dryer control system, an on-line hygrometer can be used to ensure that the feed gas is as dry as possible, maintaining generator efficiency and extending its life.