METHOD AND DEVICE FOR DESULFURIZING GAS CONTAINING SULFUR OXIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for desulfurizing gas containing sulfur oxide which has a simple configuration and can recover a by-product with a high recovery rate and high purity while curbing a load on wastewater treatment means.SOLUTION: A method for desulfurizing gas containing sulfur oxide comprises: a humidifying fluid contact step which generates second gas by bringing first gas containing the sulfur oxide in contact with humidifying fluid; a humidifying fluid separation step which generates third gas by separating at least a portion of the humidifying fluid from the second gas; a sulfur oxide removal step which removes the sulfur oxide from the third gas by bringing the third gas in contact with alkaline agent containing fluid and oxygen; a circulation step which circulates the alkaline containing fluid contacted with the third gas and the oxygen to utilize the same as the humidifying fluid; a gas removal step which removes gas from the humidifying fluid acquired through a humidifying fluid acquisition step to acquire at least a portion of the humidifying fluid separated in the humidifying fluid separation process; and a by-product recovery step which recovers a by-product generated in the sulfur oxide removal step from the humidifying fluid with gas removed therefrom. The by-product recovery step is executed only at a downstream side of the humidifying fluid acquisition step.