The present invention discloses a process for continuously removing
chlorine from the supernatant of the intermediate leaching. The supernatant of the intermediate leaching is used as the solution to be treated. The
chlorine removal agent,
bismuth oxide, is pickled and activated under high acid conditions. The activated
bismuth oxide is added to the elevated tank and continuously and stably added to the supernatant of the intermediate leaching for
chlorine removal. An alkali solution is used to adjust the pH of the
slurry after chlorine removal. The
slurry after pH adjustment is subjected to liquid-
solid separation using a
filter press. The obtained filtrate is returned to the intermediate leaching thickener of the hydrometallurgical
zinc smelting, and the obtained filter residue is subjected to regeneration treatment. An alkali solution is pre-prepared in the alkali solution tank and continuously input into the alkali washing tank, and an alkali washing reaction is carried out with the filter residue under high temperature and high alkali conditions. The alkali washing solution obtained after liquid-
solid separation using a
filter press is used to recover chlorine, and the obtained alkali washing residue is treated. The alkali washing residue is discharged to the
pickling tank for
pickling and activation and then reused in the chlorine removal process. By using the present invention, the
chloride ions in the supernatant of the intermediate leaching of a hydrometallurgical
zinc smelting system with high
silicon and low iron can be removed.