초록 ▼

A process for the removal of nitrogen oxides and soot from exhaust gases from machines and combustion installations burning heavy fuel oil by means of free-passage catalysts at increased temperatures with the addition of ammonia into the exhaust gas stream ahead of the catalysts. To make the process

A process for the removal of nitrogen oxides and soot from exhaust gases from machines and combustion installations burning heavy fuel oil by means of free-passage catalysts at increased temperatures with the addition of ammonia into the exhaust gas stream ahead of the catalysts. To make the process mre effective, the soot adhering to the catalyst surfaces is removed by burning it off and/or by friction resulting from the admixture of sand, ash or similar abrasive mixtures into the exhaust gas stream ahead of the catalysts.

대표청구항 ▼

A process for the removal of nitrogen oxides from exhaust gases and soot from a free-passage catalyst of machines and combustion apparatus of the type burning heavy fuel oil by passing the exhaust gases through said free-passage catalyst at high temperatures with the addition of ammonia into the exh

A process for the removal of nitrogen oxides from exhaust gases and soot from a free-passage catalyst of machines and combustion apparatus of the type burning heavy fuel oil by passing the exhaust gases through said free-passage catalyst at high temperatures with the addition of ammonia into the exhaust gas stream upstream of said free-passage catalyst, the improvement comprising the steps of: selectively admixing an abrasive material into said exhaust gas prior to passing said exhaust gas into said free-passage catalyst, whereby said abrasive material, through frictional contact with the soot adhering to the free-passage catalyst, removes at least a portion of the soot therefrom, selectively withdrawing at least a portion of said abrasive material after passage through said free-passage catalyst for recycle with said exhaust gas prior to the passage of said exhaust gas into said free-passage catalyst, and introducing an ignition agent into the recycled exhaust gas to combust soot remaining therein.