| 摘要 |
PURPOSE:To enhance the reducing efficiency of a particulate by a method wherein a large number of cells mutually extending in parallel across thin walls by thin metal plates and coating the surfaces of the walls with a catalyst and providing a large number of small recessed parts to the surfaces of the walls. CONSTITUTION:Small recessed parts 5 are formed on the surface of the walls of flat plates 3 and corrugated plates 4 and a gas streams are disturbed to form a large number of small gas streams colliding with the recessed parts 5. Therefore, the dry soot in gas is bonded to the recessed parts 5 to be collected in a certain degree. When the number of cells per a unit area of outer peripheral parts 12 become more than those of inner peripheral parts 13 in respective layers wound in a multiple state, the exhaust temp. of the outer peripheral parts 12 becomes lower than that of the inner peripheral parts 13 by radiation and the catalitic reaction effect of the outer peripheral parts 12 becomes lower than that of the inner peripheral parts, and much gas flows through the inner peripheral parts 13 and catalytic reaction effect is enhanced. The contact efficiency of the gas and the catalyst becomes high even in the outer peripheral parts 12 and catalytic reaction advances in the same degree as the inner peripheral parts. As a result, catalytic reaction effect is enhanced as a whole and, therefore, a particulate can further be reduced. |
