| 摘要 |
<p>PURPOSE:To enhance the removal efficiency of noxious gas by increasing the surface area of soda lime and to prevent the generation of gas having a high acidity by reducing moisture in soda lime, by contacting soda lime preliminarily dehydrated and dried with halogen type waste gas at specific temp. CONSTITUTION:A reaction cylinder 1 is filled with soda lime preliminarily heated and dried under vacuum as a solid treatment agent and heated to 200-300 deg.C by a heater 15. The waste gas formed by diluting halogen type noxious gas 3 such as Cl2, BCl3 or F2 issued from a semiconductor factory with inert gas 2 is passed through the reaction cylinder 1 to remove the noxious gas. By applying dehydration and drying pretreatment to soda lime, free water and combined water contained in soda lime can be reduced and, by preventing that the surface of soda lime is covered with moisture, the surface area of soda lime capable of contacting with waste gas can be largely secured and the generation of gas having high acidity generated by the reaction of the moisture in soda lime wit the noxious gas is preliminarily suppressed make it possible to prevent the deterioration of a treatment apparatus due to corrosion.</p> |
