The groundwater with high level initial hardness was softened with various lime dosage
varying from 30 % to 180% of the stoechiometric amount. Both the initial and final
parameters such as total hardness, calcium hardness, total alkalinity, pH were measured
and compared to get the idea of removal efficiency with different lime dosage. The
results showed that with 120 % lime dosage, the treated water has lowest total alkalinity,
magnesium hardness and total hardness compared to the other lime dosages. The total
hardness removal could achieve 60 %, while the alkalinity could get the 72 % removal.
However, the optimum lime dosage for removing calcium hardness was found to be 90%
of the stoichiometric lime dosage.