Diesel engine exhaust gas system has several catalytic modules incorporated within a single housing

摘要

A diesel engine exhaust pre-catalytic filter oxidises particles and forms nitric oxide discharging to a selective catalytic reduction (SCR) catalyst with incoming ammonia. The pre-catalyst and SCR esp. share a common housing (1) with a gas inlet (14) on one side and a gas outlet (15) on the other. The housing is sub-divided into a number of gas-tight chambers (2, 3, 4) by panels (16, 17). The modules are arranged in parallel within chambers. Each chamber contains a catalytic module (5) with a pre-catalytic element (51), pre-catalyst (512), SCR catalyst element (52) and SCR catalyst (522). Ammonia is introduced (6) into the second chamber.