| 摘要 |
<p>The present invention relates to a method of purifying flue gas desulfurization (FGD) gypsum. The method is characterized by comprising the steps of a) providing an aqueous slurry containing said FGD gypsum, b) passing said aqueous slurry to a magnetic separator, and c) contacting the FGD gypsum to be purified with a solution containing an acid and having pH below 5 in an acid washing step. The present invention also relates to the purified FGD gypsum obtained by the inventive method and to the use thereof as coating or filler pigment for paper or board.</p> |
