Catalyst arrangement for purifying exhaust gas flow of diesel engine of motor vehicle, has pipe section for guiding exhaust gas flow from one selective catalytic reduction catalyst into another selective catalytic reduction catalyst

摘要

The arrangement (1) has a selective catalytic reduction (SCR) catalyst (17) for performing selective catalytic reduction. Another SCR catalyst (19) is arranged downstream to the former SCR catalyst for performing selective catalytic reduction. A pipe section (21) is connected between the two SCR catalysts for guiding exhaust gas flow (3) from the former SCR catalyst into the latter SCR catalyst. The former SCR catalyst is designed smaller than the latter SCR catalyst. The pipe section includes a neck (25) and a venturi nozzle (27).