Chemical treatment of sabkha in Saudi Arabia

There are large bodies of saline marsh water along the coast of the Red Sea in Saudi Arabia. This type of salinewater body (sabkha) was chemically processed to produce partially desalted water. Typical sabkha consists mainly of Na+, Mg+2 and Ca+2 salts. The salts are put in contact first with ammonia (NH3) and then carbon dioxide in an attempt to convert them into chemicals such as sodium bicarbonate (NaHCO3) and ammonium chloride (NH4Cl). The conversions depend on the initial ammonia concentration (2.5-7.5 M), sabkha concentration (1.6-3.9 M), length of carbonation time (up to 3 h) and the NH3/NaCl ratio. The partially desalted water obtained could be further processed for industrial and other uses.