Charcoal treatment showed marked reduction in heavy metal, nitrate,
phosphate, total
hardness etc. in the water sample. But
due to highly absorptive and porous nature reduction in DO was also
recorded by charcoal treatment. Reduction in DO resulted in increase in BOD and COD. These three are very sensitive parameters for the water quality, thus, this was recorded as a prominent drawback of this treatment.
Marvelous response was recorded in the case of ozone treatment where 100% removal of chromium from polluted water was surprising. Most of the heavy metals were nearly washed along with reduction in acidity, nitrate,
phosphate, BOD, COD and total hardness. Similar results were obtained in the treatment of water samples of all the three sites. Ozone treatment showed significant increase in the value of DO and total solids.