PHOSPHORUS ABSORPTION BY HYDRATION AND FLUORINE RECOVERY FOR FUME EXITING KILN IN KILN PHOSPHORIC ACID PROCESS

摘要

Disclosed is a method for phosphorus absorption by hydration and fluorine recovery for a fume exiting a kiln in a kiln process for the production of phosphoric acid, comprising the following steps: a fume containing P2O5 and fluorine exiting a kiln is introduced into a hydration tower, the fume performs heat and mass transfer with the spraying liquid, with most of the phosphoric acid produced being absorbed into the spraying liquid; the phosphoric acid solution falling from the spraying finally enters the acid solution circulating and spraying system; the fume discharged from a fume outlet then passes through a phosphoric acid mist capturing tower and a mist removing and separating tower successively, such that the phosphoric acid mist entrained in the fume exiting the hydration tower is further captured.