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Phase diagram of salt water.  

Phase diagram of salt water.  

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Freeze desalination of samples of seawater from Umluj beach, Red Sea, in Saudi Arabia, was investigated by laboratory experiments using nondirect freezing. The influence of kinetic parameters including degree of crystallization, freezing–melting cycles, and gradual melting on the total dissolved solids (TDS) and salt rejection was examined. The mel...

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... desalination processes are based on the fact that ice crystals are made up of essentially pure water when the temperature of saline water is lowered to its freezing point and further heat is removed [10]. Typical binary phase diagram of salt water (Fig. 3) shows the temperature-composition fraction of NaCl relationships among the different phases of the salt water. For a binary solution of 4% NaCl, which is the salinity of the seawater samples in this study, water starts to transit from the liquid phase to the solid crys- tal phase when the temperature is decreased and lower than the ...

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... When the diffusion coefficient of Mg 2+ is sufficiently large in the refrigerant liquid phase, the growth rate of droplets will affect the concentration level in the melting stage. In other words, slow droplet growth conditions are conducive to the recovery of solutes with high yields (Badawy 2016). In the early melting period, with the increase and interconnection of melting pores, many pore channels connecting the ice interior are formed (such as Fig. 10), and the ice layer becomes loose and disintegrates, resulting in the release of a large amount of Mg 2+ in the early stage of ice melting. ...
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