Partial elimination of the water hardness by using (lime, soda and sodium carbonate): Representation of calcocarbonic balance curves

The distribution of groundwater for their use in the field domesticates or industrial often poses technical problems of corrosion or incrustation of the installations. To treat this water amounts studying the chemical composition and balances calcocarbonic of water.These balances result from the presence of ions coming from solubilization from the rocks by natural water such as (CO2−2, HCO−3, Cl−, SO2−4, Na+, K+, Mg2+, Ca2+). Accordingly we have to treat a very hard water of Hamma which is intended for the supply of the town of Contantine of drinking water and having a hardness of 60 french degrees by the use of a chemical process in the presence of lime, soda, sodium carbonate and to plot the corresponding calcocarbonic curves of balance. The results revealed that 0.16 g.L−1 of lime or 0.04 g.L−1 of soda made it possible to bring the water of Hamma close to the equilibrium calcocarbonic curve. Moreover, the use of 0.08 g.L−1 of sodium carbonate gives the best treatment