Investigation of bio-desalination potential algae and their effect on water quality

Alternative water sources should be considered when facing an increase in water demands and a decrease in freshwater supplies. Water desalination has become critical to meet increasing water demands, especially in water-stressed countries where water obtained by desalination far exceeds supplies from freshwater sources. This study aimed to investigate saline water desalination using marine algae. Factorial experiments were carried out based on a completely randomized design. Treatments were associated with four algae (Dunaliella salina, Chlorella vulgaris, Nannochloropsis oculata, and Scenedesmus quadricauda) considering different salinity (50–70 mS cm–1) in three replicates (laboratory conditions). Moreover, electrical conductivity (EC) was daily measured. The results showed no significant difference in terms of desalination between D. salina algae and the others at EC of 50–70 mS cm–1. However, a major effect was observed by increasing salinity. The results also revealed that the application of D. salina algae led to a significant reduction in chlorine, sodium, and bicarbonate levels under the same condition. The suitability of these desali-nation technologies was measured based on several criteria, including feed water quality level, energy source, removal efficiency, and energy requirement.