Internal combustion engine and method for operating same

1. A method for operating an internal combustion engine, having a gas combustion system and an exhaust gas aftertreatment system, comprising:

conducting an exhaust gas, which leaves the gas combustion system, via the exhaust gas aftertreatment system having at least one CH 4 -oxidation catalytic converter for cleaning;

determining an actual NO 2 exhaust gas value based at least in part on a measured value;

measuring a CH 4 /NO 2 mole ratio in the exhaust gas at least one of on a gas combustion system side and on an exhaust gas aftertreatment system side upstream of the at least one CH 4 -oxidation catalytic converter;

adjusting a CH 4 /NO 2 mole ratio in the exhaust gas based at least in part on the measurement to be less than or equal to 2.

2. The method according to claim 1 , further comprising:

adjusting an NO 2 proportion in the exhaust gas is adjusted so that upstream of the at least one CH 4 -oxidation catalytic converter the NO 2 proportion of a total nitrogen oxides in the exhaust gas amounts to at least one of:

at least 15%,

at least 30%, and

at least 50%.

3. The method according to claim 2 , wherein the NO 2 proportion in the exhaust gas is adjusted via at least one NO-oxidation catalytic converter of the exhaust gas aftertreatment system, which is arranged upstream of the at least one CH 4 -oxidation catalytic converter.

4. The method according to claim 3 , wherein the exhaust gas is conducted via a plurality of CH 4 -oxidation catalytic converters which are positioned one after the other and upstream of at least one CH 4 -oxidation catalytic converters via at least one NO— oxidation catalytic converter.

5. The method according to claim 2 , wherein the NO 2 proportion in the exhaust gas is adjusted by changing at least one operating parameter for the gas combustion system.

6. The method according to claim 5 , wherein the at least one operating parameter comprises at least one of a lambda value, an ignition timing, valve control times, an engine compression, and an exhaust gas proportion in an engine combustion chamber.

7. The method according to claim 5 , further comprising:

changing the at least one operating parameter for the gas combustion system such that the actual NO 2 exhaust gas value is approximated to an NO 2 exhaust gas set point value.

8. The method according to claim 1 , further comprising:

conducting the exhaust gas upstream of the at least one CH 4 -oxidation catalytic converter is conducted via an SCR-catalytic converter; and

introducing at least one of NH 3 or an NH 3 precursor substance in the exhaust gas downstream of the SCR-catalytic converter.

9. An internal combustion engine, comprising:

a gas combustion system;

a sensor configured to measure an actual NO 2 exhaust gas value, and

an exhaust gas aftertreatment system, that comprises at least one CH 4 -oxidation catalytic converter,

wherein an NO 2 proportion in the exhaust gas is adjusted in a defined manner by at least one of:

at least one measure on a gas combustion system side and

at least one measure on an exhaust gas aftertreatment system side; and

an engine control device configured to receive a measured a CH 4 /NO 2 mole ratio in the exhaust gas and adjusting a CH 4 /NO 2 mole ratio in the exhaust gas to be less than or equal to 2 based at least in part on the received measurement.

10. The internal combustion engine according to claim 9 , further comprising:

an NO-oxidation catalytic converter arranged upstream of the at least one CH 4 -oxidation catalytic converter.

11. The internal combustion engine according to claim 10 , wherein the exhaust gas aftertreatment system comprises a plurality of CH 4 -oxidation catalytic converters connected one behind the other, wherein upstream of at least one of the plurality of CH 4 -oxidation catalytic converters at least one NO-oxidation catalytic converter is arranged.

12. The internal combustion engine according to claim 10 , further comprising:

an exhaust gas turbocharger,

wherein at least one NO-oxidation catalytic converter is positioned upstream of a turbine of the exhaust gas turbocharger.

13. The internal combustion engine according to claim 9 , further comprising:

an SCR-catalytic converter arranged downstream of the at least one CH 4 -oxidation catalytic converter; and

a device positioned upstream of the SCR-catalytic converter and configured to introduce at last one of NH 3 and an NH 3 precursor substance into the exhaust gas.

14. The internal combustion engine according to claim 9 ,

wherein the sensor configured to determine an actual NO 2 exhaust gas value is at least one of downstream of the gas combustion system and upstream of the exhaust gas aftertreatment system; and

the engine control device further configured to change at least one operating parameter for the gas combustion system such that the actual NO 2 exhaust gas value is approximated to an NO 2 exhaust gas set point value.

15. The internal combustion engine according to claim 14 , wherein the engine control device determines the NO 2 exhaust gas set point value as a function of at least one operating parameter of the gas combustion system.

16. The method according to any one of the claim 1 , wherein the CH 4 /NO 2 mole ratio in the exhaust gas is smaller than 1.5.

17. The method according to any one of the claim 1 , wherein the CH 4 /NO 2 mole ratio in the exhaust gas is smaller than 1.

18. The internal combustion engine according to claim 14 , wherein the engine control device determines the NO 2 exhaust gas set point value based at least in part on a load point.

19. The internal combustion engine according to claim 9 , wherein the received CH 4 /NO 2 mole ratio in the exhaust gas is from at least one of on a gas combustion system side and on an exhaust gas aftertreatment system side upstream of the at least one CH 4 -oxidation catalytic converter.