Because of safety issues ...
Published by Marina Vasiljevic, Sole Proprietor at M ENGINEERING ZONE
Because of safety issues associated with the chlorine dosing, UV technology has experienced increased acceptance in both municipal and household systems. There are few large-scale UV water treatment plants in the United States are more than 2,000 such plants in Europe.
UV is the only disinfectant that does not create damaging by products. It effectively inactivates all micro-organisms including protozoan cysts.
The major drawbacks are:
- It is not possible to check the effectiveness of the delivered dose by measuring the residual as in the case of chemical oxidants therefore it is essential for reactor to be equipped with UV intensity sensors
- No residual effect so except of the case of the well maintained distribution network, it need to be combined with another disinfectant