THE DECARBONIZATION METHOD OF SEA WATER FOR PREPARING SEA WATER MAGNESIA

摘要

PURPOSE: Provided is a method capable of properly decarboxylating a seawater and conveniently isolating the related residue CaCO3 from slag(which is a by-product discharged from ironworks), by introducing predetermined amount of the slag to seawater for producing seawater magnesia. CONSTITUTION: The method, which is to produce seawater magnesia by decarboxylating seawater and precipitating the decarboxylated seawater with magnesium hydroxide, is characterized in that it comprises the steps of (i) introducing a crushed slag having particle size of 0.25-1 mm to seawater; (ii) filtering the dispersion and using the obtained water-supernatant for producing seawater magnesia; and (iii) sieving a remaining sludge to separate the slag and formed calcium carbonate sludge. The slag is selected from a converter slag comprising CaO, SiO, and iron oxide as main component, and MgO as auxiliary component, an electric furnace oxidizer slag, and a dephosphorus slag.