Method and device for purification of contaminated gaseous chlorine with bromine.

摘要

Method for purifying a chlorine gas stream, removing the bromine content including washing the gas with an aqueous solution comprising a saline low salt content. The chlorine gas stream is washed in a column (5) with an aqueous solution comprising a salt solution low in salt extracted from an advanced stage of electrolysers (3) producing chlorine by electrolysis of a saline. Washing the saline is performed countercurrent, preferably with the ascending gas flow, at a temperature between 10 and 35 degrees C and preferably between 15 and 20 degrees C. Also, downstream of the washing process, bromine and chlorine is separated from the salt solution by distillation using water vapor under vacuum or a gas, preferably air. The process is performed at the site of production of chlorine by electrolysis. Brine low-salt cooled before washing chlorine. The heat of cooling method is used for the distillation process. After distillation, the saline low salt content is recycled to before the electrolysis units. This recycle line takes the juvenile a purge. an independent claim for the device is also included to carry out this process, comprising a unit producing chlorine by electrolysis of saline, a washing column for chlorine gas and a circuit carrying a part of the saline low in salt, taken in an advanced stage of the electrolysers (3) in the washing column (5). The device also contains a distillation unit (7) for removing chlorine and bromine saline after the washing process. A heat exchanger (E1) cooled saline before being introduced into the column and heating the salt solution leaving the column before being introduced into the distiller.