M. E. Banihabiba - Professor Assistant, Department of Irrigation and Drainage Engineering, College of Aburaihan, University of Tehran
B Ebrazi - M.Sc. Student Irrigation and Drainage Engineering, University of Tehran

Sometimes groundwater is known as hard water due to its large amount of Calcium and Magnesium. Hygienically soapy products are less efficient using hard water. Furthermore residual lime in inner parts of boilers and radiators causes difficulties. This paper aims to study the effect of thickness of Zeolite filters (Clinoptilolite) in eliminating Calcium and Magnesium from water. Accordingly batch experiment was done on adsorption isotherm, and five tests were done using column experiments with different thicknesses for each cation using synthetic solutions with specific concentrations. Therefore the breakthrough curves were drawn for each ion using the chemical analysis results of samples. Removal efficiencies of calcium are 0.13, 0.16, 0.17, 0.20 and 0.32, and for magnesium are 0.10, 0.14, 0.16, 0.18 and 0.20 in studied thicknesses. The results imply that increasing the Zeolite thickness leads to increase the removal efficiency and Following selectivity series was found: Ca2+ 〉Mg2+ .

Zeolite, Clinoptilolite, Calcium and Magnesium elimination, groundwater