THE METHOD OF NEUTRALIZATION PHOSPHO-GYPSUM USING FLUIDIZED BED BOILER FLY ASH AND USE THEREOF

摘要

Disclosed is a manufacturing method of a cement setting retarder using fly ash from a fluidized bed boiler. According to the present invention, the manufacturing method of a cement setting retarder comprises the following steps of: preparing phosphogypsum, as a starting material, having pH of 4.0 at most generated in a process of extracting phosphoric acid; and neutralizing the phosphogypsum to have pH of at least 7.0 by mixing the phosphogypsum with fly ash obtained from circulating fluidized bed boiler. According to the present invention, neutralized phosphogypsum applicable as a cement setting retarder can be obtained. Through the present invention, discarded or stowed resources can be usefully used to resolve problems of waste and stowage, and can be reused.