Compact dual leg NOx absorber catalyst device and system and method of using the same

A method for treating exhaust gases from an internal combustion engine, the method comprising:

• transporting the exhaust gases from the engine to a housing that contains a first flow path, a second flow path, and a chamber downstream of the first and second flow paths, the flow paths having coaxially arranged portions, the first and second flow paths flowing into the chamber;
• selectively directing the exhaust gases between the first flow path and the second flow path;
• providing a first NOx adsorbing catalyst contained in the first flow path, the first NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx;
• and
• selectively directing a gas containing a reducing agent to flow into the first NOx adsorbing catalyst to periodically regenerate the catalyst.

A method for treating exhaust gases from an internal combustion engine, the method comprising:

• providing a housing that has a first and second flow conduit in a coaxial arrangement, the housing containing a chamber downstream of the first and second flow conduit, the first flow conduit being axially inward of the second flow conduit, the first and second flow conduit flowing into the chamber;
• providing a first NOx adsorbing catalyst in the first flow conduit, the first NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx;
• selectively directing the exhaust gases through the first and second flow conduits;
• and
• when directing gases through the second flow conduit, selectively directing a gas containing a reducing agent to flow through the first NOx adsorbing catalyst.

An apparatus for treating exhaust gases from an internal combustion engine, the apparatus comprising:

• a housing having a first flow path and a second flow path for transporting the exhaust gases from the engine, the housing containing a chamber downstream of the first and second flow paths, the flow paths having coaxially arranged portions, the first and second flow paths flowing into the chamber;
• a gas directing device for selectively directing the exhaust gases between the first flow path and the second flow path;
• and
• a first NOx adsorbing catalyst contained in the first flow path, the first NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx.

A system for treating exhaust gases from an internal combustion engine, the system comprising:

• a housing having a first flow path and a second flow path for transporting the exhaust gases from the engine, the flow paths having coaxially arranged portions;
• a gas directing device for selectively directing the exhaust gases between the first flow path and the second flow path;
• a first NOx adsorbing catalyst contained in the first flow path, the first NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx;
• a first reductant supply source capable of selectively directing a gas containing a reducing agent to flow into the first NOx adsorbing catalyst;
• a second NOx adsorbing catalyst contained in the second flow path, the second NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx;
• a first catalyzed diesel particulate filter contained in the first flow path upstream of the first NOx adsorbing catalyst wherein the second flow path has a portion that bypasses and is coaxial with the first catalyzed diesel particulate filter and the first NOx adsorbing catalyst;
• and
• a second catalyzed diesel particulate filter contained in the second flow path upstream of the second NOx adsorbing catalyst wherein the first flow path has a portion that bypasses and is coaxial with the second catalyzed diesel particulate filter and the second NOx adsorbing catalyst.

An apparatus for treating exhaust gases from an internal combustion engine, the apparatus comprising:

• a housing having a first flow path and a second flow path for transporting the exhaust gases from the engine, the flow paths having coaxially arranged portions;
• a gas directing device for selectively directing the exhaust gases between the first flow path and the second flow path;
• a first NOx adsorbing catalyst contained in the first flow path, the first NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx;
• a second NOx adsorbing catalyst contained in the second flow path, the second NOx adsorbing catalyst requiring periodic regeneration to purge accumulated NOx, wherein the second NOx catalyst is downstream from and in the same general plane as the first NOx adsorbing catalyst;
• a first catalyzed diesel particulate filter contained in the first flow path upstream of the first NOx adsorbing catalyst wherein the second flow path has a portion that bypasses and is coaxial with the first catalyzed diesel particulate filter and the first NOx adsorbing catalyst;
• and
• a second catalyzed diesel particulate filter contained in the second flow path upstream of the second NOx adsorbing catalyst wherein the first flow path has a portion that bypasses and is coaxial with, and axially outward relative to, the second catalyzed diesel particulate filter and the second NOx adsorbing catalyst.