Method for the management of phosphogypsum

Abstract

A method for the management of phosphogypsum consists in that a reactor (2) is charged with apatite and/or phosphorite phosphogypsum and with an aqueous or ammoniacal solution of ammonium carbonate and/or bicarbonate from a pre-reactor (1), at 1: (0.1-4) ratio of phosphogypsum to the aqueous or ammoniacal solution of ammonium carbonate and/or bicarbonate, the entire contents are stirred at −10° C. to 200° C. for at least 2 minutes, CO2 being released in the course of the process is directed to the pre-reactor (1), and the post-reaction mixture is directed to a filter (3) to obtain an aqueous ammonium sulphate solution, whereas the precipitate from the filter (3) is heat-treated, followed by dissolving it in nitric acid in a reactor (5), and the resultant suspension is filtered through a filter (6) to obtain an aqueous calcium nitrate solution, and CO2 being released in the reactor (5) is recirculated to the pre-reactor (1) wherein CO2 is reacted with ammonia in an aqueous solution to obtain the aqueous or ammoniacal solution of carbonate and/or bicarbonate which is directed to the reactor (2), with the process for obtaining the aqueous or ammoniacal solution of ammonium carbonate and/or bicarbonate being conducted until the pH 7-12 of the solution is reached.

Dependencies are inferred from the claim text.