Reaction Characteristics of Calcination and Decomposition of Phosphogypsum in a Bubbling Fluidized Bed

A bubbling fluidized bed reactor is designed to investigate the high-temperature calcination and decomposition characteristics of phosphogypsum (PG). The reactor employs electric heating, and a lifting discharge tube is installed in the middle of the air distributor to allow flexible switching between batch and continuous feeding modes. The batch test results show that the solid-phase bed materials with a PG particle size of 0.27-0.55 mm and a coal particle size of 0.55-0.83 mm are found to have uniformly mixed at a PG/coal mass ratio of 5:1 and calcined at a high temperature of 1100 °C for 30 min. PG completely decomposes to yield mainly CaS and a small amount of Ca