A. Messaitfa  , K. Baouia  , A. Meghezzi  , M. Saidi  , 
    Geothermal Water Quality in Oued R’hir Valley (Southeast Algeria).Scaling Problem and Hardness Treatment,
    Research Journal of Agronomy,
    Volume 1,Issue 2,
    2007,
    Pages 80-83,
    ISSN 1815-9354,
    rjagr.2007.80.83,
    (https://makhillpublications.co/view-article.php?doi=rjagr.2007.80.83)
    Abstract: The conducts of drinking water supply in Oued R’hir valley, have been for a long time jeopardized by encrusting. Geothermal water, the only source of drinking water, has a high capacity tendency to form scale is the origin of this phenomenon. This water is highly mineralized (2.5 g L <SUP>1</SUP>) and of a very high degree of hardness (1120 mg L <SUP>1</SUP> as CaCO<SUB>3</SUB>). The maximum scaling rate (1.4 cm y <SUP>1</SUP>) is observed in the conducts located at the first kilometer of the water source, where the water temperature and pressure are very favorable. The calcareous mass produced is estimated at 1.6 g L <SUP>1</SUP>, or 2243 t y <SUP>1</SUP>. The treatment results show that hydrated lime process has very low efficiency (11.5%) facing water hardness, compared with that obtained by the sodium carbonate (61%). They, thus testify that water hardness dominated is the permanent hardness. Yet the process with Na<SUB>2</SUB>CO<SUB>3</SUB> added to produced water 255 mg L <SUP>1</SUP> of the sodium with the initial water content (323 mg L <SUP>1</SUP>) for each 682 mg L <SUP>1</SUP> as CaCO<SUB>3</SUB> of water hardness removed.
    Keywords: Hardness;decarbonation;hydrated lime;sodium carbonate;geothermal waters