Process and apparatus for forming an aqueous chloride bleach

摘要

The specification discloses a process for regenerating aqueous chloride leach liquors. The process involves roasting aqueous chloride leach liquor to produce metal oxide and a gas containing HC1. The gas containing HC1 is passed through a preconcentrator where it is contacted with spent aqueous chloride leach liquor. The enthalpy of the gas evaporates water from the spent liquor thereby concentrating it. At the same time the spent liquor absorbs HC1. HC1 not absorbed in the preconcentrator is contacted with water to form hydrochloric acid. The hydrochloric acid may be mixed with the concentrated spent liquor and re-used. Apparatus for operating the process is also disclosed.