Patent ID: 7704370
Filing Date: 2010-04-27
Classification: C01D,C25B,Y02P

Abstract:
1. An integrated process for the joint production of sodium carbonate and a chlorine derivative according to which an aqueous sodium chloride solution is electrolysed in a cell with an ion permselective membrane in order to produce, on the one hand, chlorine which is converted in a chlorine derivative production unit and, on the other, an aqueous solution comprising sodium hydroxide, the aqueous solution comprising sodium hydroxide is carbonated, the resulting carbonated aqueous solution is evaporated to produce sodium carbonate crystals, which are separated, and a mother liquor, characterized in that the carbonation is carried out, at least partly, using carbon dioxide present in a flue gas issuing from a cogeneration unit supplying the integrated process with electricity and/or with steam, wherein at least a part of a steam produced in a cogeneration unit is used to evaporate the carbonated aqueous solution.