Apparatus for catalytic reduction of nitrogen oxides-containing exhaust gases from IC engines has diffuser with exhaust gas channels having increasing cross-section in flow direction between mixer and converter
A diffuser (6) with a number of exhaust gas channels (21) having an increasing cross-section in the flow direction is provided between the mixer (2) and the converter (7). The apparatus for the catalytic reduction of NOx-containing exhaust gases from IC engines comprises an exhaust gas line (1) connected to an exhaust gas outlet of the engine; a feed (3) for introducing urea as reductant into the exhaust gas line; a mixer (2) arranged in the exhaust gas line in the exhaust gas flow direction downstream of the feed for the reductant; and a catalytic converter (7) connected to the mixer. The mixer has a number of channels through which the gas can flow. A diffuser (6) with a number of exhaust gas channels (21) having an increasing cross-section in the flow direction is provided between the mixer (2) and the converter (7). Preferred Features: The free flow cross-section at the inlet of the diffuser corresponds to the free flow cross-section at the outlet of the mixer. The diffuser has a cell density corresponding to the cross-sectional shape of the individual channels of the mixer.
