| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To detoxify, in a dry state, exhaust gas which contains HF and SOx and is generated when PFC (a perfluoro compound) which is discharged from a factory for manufacturing semiconductors or liquid crystals is decomposed. <P>SOLUTION: In a SOx removing step, SOx is removed from the exhaust gas containing HF and SOx, and the resultant gas is brought into contact with solid Ca(OH)<SB>2</SB>. A Ca(OH)<SB>2</SB>-packed column 101 has: a Ca(OH)<SB>2</SB>layer 110 held on a meshed plate 102; an HF-containing gas introducing port in the lower part; and an HF-free gas discharging port in the upper part. A blower (or an ejector) 104 is arranged at the HF-free gas discharging port for sucking/discharging the gas in the column 101. When SOx remains in the HF-containing gas, the temperature of the layer 110 is preferably adjusted to be 100 to 310°C. As a result, HF can be made harmless without using water. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
