A comparative study between three methods of the remineralization of the osmosis water produced from desalination plant in the south of Morocco [Etude comparative entre trois méthodes de reminéralisation de l'eau osmosée des stations de dessalement et de déminéralisation au sud Marocain]

Desalination is the process of removing salt and other minerals,especially from sea water to produce potable water for household or irrigation purpose. waters produced by desalination plants cannot be directly used as they are unpalatable,corrosive and unhealthy. remineralization is essential in order to overcome these problems. this study was conducted to examine the performances of the remineralization process adopted for three desalination units installed by the national office of drinking water and electricity (onee) in laâyoune,daoura and agti elghazi. remineralization processes are necessary to equilibrate the water to avoid aggressiveness and corrosion in pipelines and to re-introduce some ions essential for human health. the distillate water produced by reverse osmosis in laâyoune units is remineralized by adding hydrated lime and carbon dioxide. the remineralization process in daoura's plant normally requires the application of sodium bicarbonate and calcium chloride. a commonly used operation in the agti elghazi's remineralization process is to pass demineralized water dosed with co2 through a bed of calcite.in the present study,the evolution of different indicators including calco-carbonic equilibrium,total alkalinity,ph,phs langelier saturation and larson index were analyzed to evaluate the quality of the product water before distribution in order to study the efficiency,performance of remineralization in each desalination plant and to compare these methods both qualitatively and economically.