ASSEMBLY AND METHOD FOR REDUCING NITROGEN OXIDES, CARBON MONOXIDE AND HYDROCARBONS IN EXHAUSTS OF INTERNAL COMBUSTION ENGINES

• US 20110265451A1
• Filed: 06/16/2010
• Published: 11/03/2011
• Est. Priority Date: 04/28/2010
• Status: Active Grant

• Current Assignee: Tecogen Inc.
• Original Assignee: Tecogen Inc.
• Inventors: Panora, Robert A., Gehret, Joseph B., Roser, Ranson
• Granted Patent: US 8,578,704 B2
• Time in Patent Office: Days
• US Class Current: 60/274
• CPC Class Codes: F01N 13/009 having two or more separate purifying devices arranged in series
• CPC Class Codes: F01N 13/0097 the purifying devices are arranged in a single housing
• CPC Class Codes: F01N 2240/36 an exhaust flap
• CPC Class Codes: F01N 3/0205 using heat exchangers
• CPC Class Codes: F01N 3/04 using liquids
• CPC Class Codes: F01N 3/05 by means of air, e.g. by mixing exhaust with air silencers working by addition of air to exhaust F01N1/14; arrangements for the supply of additional air for the thermal or catalytic conversion of noxious components of exhaust F01N3/30 ; in tailpipes F01N13/082
• CPC Class Codes: F01N 3/101 Three-way catalysts
• CPC Class Codes: F01N 3/2046 Periodically cooling catalytic reactors
• CPC Class Codes: F01N 3/2882 Catalytic reactors combined or associated with other devices, e.g. exhaust silencers or other exhaust purification devices combined with absorbents or adsorbents only F01N3/0814; combined with particulate filters F01N3/035
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An assembly and method for reducing nitrogen oxides, carbon monoxide and hydrocarbons in exhausts of internal combustion engines, wherein the exhaust is acted upon in a first stage catalytic converter. A first portion of the first stage catalytic converter output is cooled and a second portion of the catalytic converter output is not cooled. The cooled and not cooled exhausts are united and directed to a second stage catalytic converter. Air is injected into a selected one of (1) the not cooled exhaust prior to the juncture thereof with the cooled exhaust, and (2) the combined cooled and not cooled exhausts after the juncture thereof.

Claims

1. An assembly for reducing nitrogen oxides, carbon monoxide and hydrocarbons in internal combustion engine exhausts, the assembly comprising:

a first exhaust conduit having an exhaust receiving end for connecting to and extending from an internal combustion engine;

a first stage catalytic converter means in communication with a dispensing end of said first exhaust conduit;

cooling means disposed on said first stage catalytic converter means for cooling a first portion of engine exhausts received from said first exhaust conduit;

a first outlet conduit for facilitating movement of the cooled first portion of engine exhausts from said first stage catalytic converter means;

a second outlet conduit for facilitating movement of a second portion of engine exhausts received from said first stage catalytic converter means;

an air injection conduit in communication with said second outlet conduit for cooling the second portion of engine exhausts;

a second exhaust gas conduit in communication with said first outlet conduit and said air injection conduit; and

a second stage catalytic converter in communication with said second exhaust gas conduit and having an exhaust emitting outlet.

2. The assembly in accordance with claim 1 wherein said first stage catalytic converter means comprises a plurality of catalytic converters.

3. The assembly in accordance with claim 1 wherein said means for cooling comprises coils for a cooling medium.

4. The assembly in accordance with claim 1 wherein said means for cooling comprises cooling medium injection means, the cooling medium being adapted to vaporize to reduce the temperature of the first portion of the engine exhausts.

5. The assembly in accordance with claim 3 wherein said coils are adapted to reduce the temperature of said first portion of said engine exhausts to about 280°

F.

6. The assembly in accordance with claim 1 wherein said first outlet conduit is provided with a temperature adjusting valve.

7. An assembly for reducing nitrogen oxides, carbon monoxide and hydrocarbons in internal combustion engine exhausts, the assembly comprising:

a first exhaust conduit having an exhaust receiving end connected to and extending from an internal combustion engine;

a first stage catalytic converter means in communication with a dispensing end of said first exhaust conduit;

cooling means in communication with said first stage catalytic converter means for cooling a first portion of engine exhausts received from said first stage catalytic converter means;

a cooled exhaust conduit extending from said cooling means;

a cooling means by-pass conduit in communication with said first stage catalytic converter and said cooled exhaust conduit;

a second stage catalytic converter in communication with said cooled exhaust conduit and said cooling means by-pass conduit;

an air injection conduit in communication with said cooled exhaust conduit; and

an exhaust outlet extending from said second stage catalytic converter.

8. The assembly in accordance with claim 7 wherein said first stage catalytic converter means comprises a plurality of catalytic converters.

9. The assembly in accordance with claim 7 wherein said cooling means comprises coils for a cooling medium.

10. The assembly in accordance with claim 7 wherein said cooling means comprises a cooling medium injection means, the cooling medium being adapted to vaporize to reduce the temperature of the first portion of the engine exhausts.

11. The assembly in accordance with claim 7 and further comprising a mixing valve disposed proximate a juncture of said cooled exhaust conduit and said by-pass conduit.

12. A method for reducing nitrogen oxides, carbon monoxide and hydrocarbons in exhausts of spark-ignited gaseous fueled internal combustion engines, the method comprising the steps of:

directing the exhausts from the engine to a first stage catalytic converter;

directing a first portion of exhaust output from the first stage catalytic converter to a cooling means and thence to a cooled exhaust conduit;

directing a second portion of exhaust output from the first stage catalytic converter to a non-cooled exhaust gas conduit;

uniting the first and second portions of exhaust gas and directing the united first and second portion to a second catalytic converter; and

injecting air into a selected one of (1) the non-cooled exhaust conduit, and (2) the united cooled and non-cooled exhausts after the uniting thereof.

13. A method for reducing nitrogen oxides, carbon monoxide and hydrocarbons from exhausts of internal combustion engines, the method comprising the steps of:

conveying the engine exhaust to a first stage catalytic converter means,

cooling a first portion of the engine exhaust in the first stage catalytic converter means and removing the cooled first portion from the catalytic converter means through a first outlet conduit;

removing a non-cooled second portion of the engine exhaust from the catalytic converter means through a second outlet conduit;

injecting air into the second outlet conduit;

conveying the non-cooled second portion of the engine exhaust and the injected air to the second exhaust gas outlet conduit to join with the cooled first portion of the engine exhaust in the second exhaust gas outlet conduit;

directing the exhaust in the second exhaust gas outlet conduit to a second stage catalytic converter; and

discharging exhaust from the second stage catalytic converter;

whereby to provide engine exhausts of less nitrogen oxides and less carbon monoxide content.

14. A method for reducing nitrogen oxides, carbon monoxide and hydrocarbons from exhausts of internal combustion engines, the method comprising the steps of:

conveying the engine exhaust to a first stage catalytic converter;

conveying the engine exhaust from the first stage catalytic converter in part to a cooling means and in part to a cooling means by-pass;

mixing exhausts from the cooling means and the cooling means by-pass in a cooled exhaust conduit;

injecting air into the cooled exhaust conduit;

directing the exhausts from the cooling means, and from the cooling means by-pass, and the injected air, to a second stage catalytic converter; and

discharging the engine exhausts from the second stage catalytic converter;

whereby to provide engine exhausts of less nitrogen oxides and less carbon monoxide content.

15. An assembly for reducing nitrogen oxides, carbon monoxide and hydrocarbons in internal combustion engine exhausts, the assembly comprising:

a first exhaust conduit having an exhaust receiving end for connecting to and extending from an internal combustion engine;

a first stage catalytic converter means in communication with a dispensing end of said first exhaust conduit;

an outlet conduit for facilitating movement of engine exhausts from said first stage catalytic converter means;

cooling means for cooling engine exhausts in said outlet conduit;

an air injection conduit in communication with said outlet conduit for cooling the engine exhausts; and

a second stage catalytic converter in communication with said outlet conduit and having an exhaust emitting outlet.

16. The assembly in accordance with claim 15 wherein said first stage catalytic converter means comprises a plurality of catalytic converters.

17. The assembly in accordance with claim 15 wherein said means for cooling comprises coils for a cooling medium.

18. The assembly in accordance with claim 15 wherein said means for cooling comprises cooling medium injection means, the cooling medium being adapted to vaporize to reduce the temperature of the engine exhausts withing said outlet conduit.

19. An assembly for reducing nitrogen oxides, carbon monoxide and hydrocarbons in internal combustion engine exhausts, the assembly comprising:

a first exhaust conduit having an exhaust receiving end connected to and extending from an internal combustion engine;

a first stage catalytic converter means in communication with a dispensing end of said first exhaust conduit;

cooling means in communication with said first stage catalytic converter means for cooling the engine exhausts received from said first stage catalytic converter means;

a cooled exhaust conduit extending from said cooling means;

an air injection conduit in communication with said cooled exhaust conduit;

a second stage catalytic converter in communication with said cooled exhaust conduit; and

an exhaust outlet extending from said second stage catalytic converter.

20. The assembly in accordance with claim 19 wherein said first stage catalytic converter means comprises a plurality of catalytic converters.

21. The assembly in accordance with claim 19 wherein said cooling means comprises a cooling medium injection means, the cooling medium being adapted to vaporize to reduce the temperature of the engine exhausts.

22. A method for reducing nitrogen oxides, carbon monoxide and hydrocarbons from exhausts of internal combustion engines, the method comprising the steps of:

conveying the engine exhaust to a first stage catalytic converter means;

removing the cooled exhausts from the catalytic converter means through an outlet conduit;

cooling the engine exhausts in the outlet conduit;

injecting air into the outlet conduit;

directing the exhaust in the outlet conduit to a second stage catalytic converter; and

discharging exhaust from the second stage catalytic converter;

whereby to provide engine exhausts of less nitrogen oxides and less carbon monoxide content.

23. A method for reducing nitrogen oxides, carbon monoxide and hydrocarbons from exhausts of internal combustion engines, the method comprising the steps of:

conveying the engine exhaust to a first stage catalytic converter;

conveying the engine exhaust from the first stage catalytic converter to a cooling means;

directing exhausts from the cooling means to a cooled exhaust conduit;

injecting air into the cooled exhaust conduit;

directing the exhausts from the cooling means, and the injected air, to a second stage catalytic converter; and

discharging the engine exhausts from the second stage catalytic converter;

whereby to provide engine exhausts of less nitrogen oxides and less carbon monoxide content.