| 摘要 |
<p>PURPOSE:To efficiently remove NOx, by contacting NOx with a catalyst in the presence of O2 to oxidize and absorb the same by the catalyst and stopping the flowing of exhaust gas at the point of time when absorbing efficiency was lowered to contact the catalyst with a reducing agent to recover the oxidizing/ absorbing capacity thereof. CONSTITUTION:NOx-containing exhaust gas is introduced into a catalyst A through a cock C1 to react NOx in exhaust gas in the catalyst in the coexistence of O2 to be absorbed by the catalyst. The exhaust gas is discarded into the atmosphere through a cock C2 while NOx is exhausted. At the point of time when the removing capacity of the catalyst was lowered, the cocks C1, C2 are changed over and exhaust gas is introduced into a catalyst B. During this time, reducing gas such as H2 is introduced into the catalyst A through a cock C3 to reduce NOx absorbed and oxidized in the catalyst. The treated gas issued from the catalyst A is discarded into the atmosphere but, when there is the unreacted reducing agent, the treated gas is introduced into the catalyst B to oxidize the reducing agent.</p> |
