Exhaust emission control device

Abstract

Fuel added to exhaust gas is uniformly afforded to catalytic surfaces of a NO x -adsorption reduction catalyst so that overall regeneration of the NO x -adsorption reduction catalyst proceeds efficiently. The invention is directed to an exhaust emission control device with the NO x -adsorption reduction catalyst incorporated in an exhaust pipe (exhaust flow passage) for guidance of the exhaust gas 9 from an engine 1 and with an fuel addition device (fuel addition means) 13 arranged for addition of fuel as a reducing agent to the exhaust pipe (exhaust flow passage) 11 upstream of the reduction catalyst 12 (exhaust flow passage) 11 , a dispersion plate 15 being arranged between a position of adding the fuel by the fuel addition device 13 and the NO x -adsorption reduction catalyst 12 for dispersing the exhaust gas 9 to stimulate dispersion of the added fuel.

1 . An exhaust emission control device wherein a NO x -adsorption reduction catalyst is incorporated in an exhaust flow passage for guiding exhaust gas from an engine, fuel addition means for addition of fuel as reducing agent being provided in the exhaust flow passage upstream of the reduction catalyst, a dispersion plate being provided between a position of adding fuel by the fuel addition means and the reduction catalyst so as to disperse the exhaust gas to stimulate dispersion of the added fuel. 
     
     
         2 . An exhaust emission control device according to  claim 1 , wherein the dispersion plate is composed of at least either of punching metal and metal mesh. 
     
     
         3 . An exhaust emission control device according to  claim 1 , wherein a catalytic regenerative particulate filter is arranged just behind the NO x -adsorption reduction catalyst. 
     
     
         4 . An exhaust emission control device according to  claim 2 , a catalytic regenerative particulate filter is arranged just behind the NO x -adsorption reduction catalyst.