Separation and recovery method for mixed gas of hydrogen chloride and sulfur dioxide

The invention relates to a separation and recovery method for a mixed gas of hydrogen chloride and sulfur dioxide. The method includes: step 1. firstly subjecting the sulfonation reaction generated mixed gas of hydrogen chloride and sulfur dioxide to washing by a bubbler, letting the mixed gas enter the bubbler to remove other substances decomposing after encountering water so as to obtain the gases hydrogen chloride, sulfur dioxide and water vapour; step 2. conducting primary falling film absorption; step 3. carrying out secondary filler absorption; step 4. performing sulfur dioxide filler absorption; and step 5. conducting tail gas treatment. The method provided by the invention utilizes the differences between the gases to conduct absorption conditionally so as to differentiate the two gases, turns waste into treasure to re-enter the production link, thus reducing environmental pollution and also saving the cost of production.