Exhaust gas catalyser with recirculation

摘要

The exhaust gas catalyser is filled with two separate blocks (2,3) of monolithic catalyser material. They are surrounded by casings (4) which may have a series of ridges and grooves which interdigitate with ridges and grooves in the outer casing (1). Exhaust gases enter through a funnel-shaped portion (5) with a flow restrictor. This causes an increase in gas velocity and a drop in pressure, aspirating gas through a recirculation pipe (10) from the output funnel-shaped portion (6). The pipe may be a separate pipeline or may be formed as an integral part of the wall of the casing.