The Ammonia (NH3-N) levels in the ground water from Ranney wells, being fed to the Old plant at Okhla was much higher (varying from 2.2 to 6 ppm) than permissible WHO limit. For treatment of such large concentrations, a theoretical dosing of 20 to 40 ppm of chlorine, much beyond the available capacity of existing installation, would have been required. In addition, dosing of such high quantity of chlorine leads to unpleasant tastes & production of cancer causing organic compounds.
SUEZ has been very sensitive about the public health and has been on the forefront in the ensuring safe drinking water to the population in its area of operation. To solve this particular issues ammonia level in Okhla plant, it was recommended that Biological Nitrification and Ozone treatment must be introduced to treat contaminated potable water before supplying it to the network, in order to improve its odour, taste, colour and the bacteriological characteristics.
The Nitrification unit ensures Biological oxidation of Ammonia to bring it below the WHO permissible limit
Ozone, a powerful oxidising agent from the ozonation unit, enhances the water quality & efficiently takes care of the Bacteria, viruses, amoeba & algae.
The Ganga water being used earlier for blending with Ranney well water is now available to meet the increased water demand.