METHOD FOR RECOVERING CONCENTRATED SULPHUR DIOXIDE FROM WASTE GASES CONTAINING SULPHUR DIOXIDE

摘要

A method is disclosed for recovering concentrated sulphur dioxide from waste gases. The method is of the type wherein the gas is treated with water or aqueous solutions or substances binding sulphur dioxide, preferably sodium citrate solution. The method is carried out in an absorption device. The absorbed sulphur dioxide is distilled in a column still with steam. The steam-SO2 mixture discharged from the still compressed anx the steam is caused to at least partially condensate in a heat exchanger used in generating the steam to be fed into the still. The method results in a reduced requirement as regards the energy for operation of the method.