Investigations of Dodoma Municipal Hard Water: (Part 1): Review of Hard Water Treatment Processes and Identification of Contaminants
[1]
Morris F. Hiji, College of Earth Sciences, University of Dodoma, Dodoma, Tanzania.
[2]
Justin W. Ntalikwa, College of Earth Sciences, University of Dodoma, Dodoma, Tanzania.
In this work, a preliminary investigation of the quality of Dodoma municipal water as well as a review of potential methods for removing hardness from this water were undertaken. The water quality parameters such as pH, titratible residue, total hardness, carbonate hardness, calcium, magnesium, fluoride, nitrate, sulphate and iron ions were measured using standard procedures. The results were compared with allowable levels for drinking water. It was observed that the calcium ions spanned the range 105 -217 mg/L which is greater than the allowable range of 50-100 mg/L. The magnesium ions spanned the range of 31-217 mg/L which is lower than the permissible level of 500-1000 mg/L. The other parameters studied were observed to be within the permissible levels. It was concluded that the hardness of this water was due to calcium ions/salts which are introduced by underground rocks containing limestone and dolomite. The review of methods that can be used to remove this hardness suggested that grape and Moringa seeds and powder can be used as they are potential adsorbents and that they are easily available in Dodoma. These materials will therefore be amenable for investigation of removal of unwanted salts in part II of this work.
Dodoma Municipality, Hard Water, Water Contaminants, Water Treatment Processes
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