METHOD FOR PRODUCING TREATMENT LIQUID FOR DECARBOXYLATING SEAWATER HAVING LOW CONTENT OF SILICA

摘要

PURPOSE: Provided is a method for producing a treatment liquid for decarboxylating seawater having extremely low content of silica by using slag which is a byproduct generated in ironworks. CONSTITUTION: The method comprises the steps of decarboxylating seawater and precipitating magnesium hydroxide from the seawater. The decarboxylation step is characterized by using slag eluate produced by crushing slag into particles having size of 45 micrometer or less, injecting water, adjusting pH of the solution to 11.5-11.8, and then filtering the solution. The slag is selected from blast furnace slag, electric furnace oxidizer slag and dephosphorus slag comprising, as main components, CaO, SiO2 and iron oxide and, as an auxiliary component, MgO.