| 摘要 |
<p>PURPOSE:To purify acidic waste gases economically and efficiently with a small- sized device by coating an alkaline material on a finely-divided powder filter aid layer precoated on a bag filter surface, and passing the acidic-gas-contg. waste gas through this. CONSTITUTION:In order to prevent clogging with time, a finely-divided powder filter aid 3 is precoated on the surface of a bag filter 2 and an alkaline material 4 for trapping the acidic gases included in the gas to be treated is coated on the filter aid layer. The gas to be treated is sucked through a suction duct 5 by a suction ventilation device, is passed through a filter device 1, where it is purified with the bag filter 2 coated with the aid 3 and the material 4, thence it is exhausted through an exhaust duct 6. When the alkali layer has deliquesced, only the alkali layer is shaken off, and further when the pressure drop has increased, the finely- divided powder layer is easily removed as well. The material 4 and aid 3 accumulated on the bottom of the device 1 are recovered from a recovery port 7 and are recycled.</p> |
