SULFUROUS ACID GAS RECOVERY METHOD

摘要

PROBLEM TO BE SOLVED: To provide a method for recovering sulfur dioxide while suppressing impurity amount.

SOLUTION: In the sulfur dioxide recovery method, an absorption step (a) for absorbing sulfurous acid gas in an organic solvent by bringing a gas mixture containing sulfurous acid gas into contact with the organic solvent with a vapor pressure 0.5 kPa or lower at 25°C in a column 1 of a counter flow type contact apparatus and a separation step (b) for releasing sulfurous acid gas from the organic solvent subjected to the absorption step at a pressure lower than that in the absorption step by using a distillation tower 5 and a vacuum pump 8, are carried out.

COPYRIGHT: (C)2004,JPO