| 摘要 |
<p>A slurry volume in a liquid storage tank at a lower part of an absorption column is reduced while a blast air quantity is minimized and purity of resulting gypsum is secured. A sub-liquid storage tank (3) is provided to a side portion of an absorption column (1) and the bottom portions of the sub-liquid storage tank (3) and an absorption column liquid storage tank (2) are connected through a liquid flow portion (11), and air is blown from air diffusion devices (6) installed at the bottom portions of the absorption column liquid storage tank (2) and the sub-liquid storage tank (3) so that a slurry which is oxidized insufficiently in the absorption column liquid storage tank (2) is oxidized completely in, and withdrawn from, the sub-liquid storage tank (3).</p> |
