System and method for processing greenhouse gases

1. A system for processing greenhouse gases comprising:

a collection subsystem configured to collect a gaseous mixture comprising carbon dioxide and methane;

a combustion subsystem configured to combust said methane in said gaseous mixture and output a gaseous combustion effluent, wherein said combustion subsystem generates electrical energy, water and additional quantities of said carbon dioxide;

an air mover introducing ambient air to said gaseous combustion effluent downstream of said combustion subsystem, said ambient air cooling said gaseous combustion effluent and diluting said carbon dioxide in said gaseous combustion effluent, thereby producing an ambient air/combustion effluent mixture, wherein said gaseous combustion effluent has a first carbon dioxide concentration and said ambient air/combustion effluent mixture has a second carbon dioxide concentration, wherein said second carbon dioxide concentration is less than said first carbon dioxide concentration, and wherein said second carbon dioxide concentration ranges from at least 5 percent by weight to less than said first carbon dioxide concentration; and

a separation subsystem configured to separate said carbon dioxide from said ambient air/combustion effluent mixture, said separation subsystem comprising:

a heat exchanger positioned to contact said ambient air/combustion effluent mixture and lower a temperature of said ambient air/combustion effluent mixture, thereby yielding a cooled mixture;

a desiccant positioned to contact said cooled mixture and remove at least a portion of said water from said cooled mixture, thereby yielding a cooled/dried mixture; and

a physisorption material positioned to contact said cooled/dried mixture and remove at least a portion of said carbon dioxide from said cooled/dried mixture.

2. The system of claim 1 further comprising a landfill, wherein said gaseous mixture is landfill gas.

3. The system of claim 1 wherein said gaseous mixture comprises about 45 to about 55 percent by weight of said carbon dioxide and about 55 to about 45 percent by weight of said methane.

4. The system of claim 1 wherein said combustion subsystem comprises at least one of an internal combustion engine and a turbine.

5. The system of claim 1 wherein said physisorption material comprises a zeolite.

6. The system of claim 1 further comprising a separator configured to separate said carbon dioxide from said gaseous mixture prior to said gaseous mixture passing to said combustion subsystem.

7. The system of claim 1 wherein said physisorption material is at a first temperature and said cooled/dried mixture is at a second temperature, and wherein said second temperature is at most 10 degrees Celsius warmer than said first temperature.

8. The system of claim 1 wherein said second carbon dioxide concentration ranges from at least 10 percent by weight to less than said first carbon dioxide concentration.

9. The system of claim 1 wherein said second carbon dioxide concentration ranges from at least 12 percent by weight to less than said first carbon dioxide concentration.

10. A method for processing greenhouse gases comprising:

collecting a gaseous mixture comprising carbon dioxide and methane;

combusting said methane to generate electrical energy and output a gaseous combustion effluent;

introducing ambient air to said gaseous combustion effluent to cool said gaseous combustion effluent and to dilute said carbon dioxide in said gaseous combustion effluent, thereby producing an ambient air/combustion effluent mixture, wherein said gaseous combustion effluent has a first carbon dioxide concentration and said ambient air/combustion effluent mixture has a second carbon dioxide concentration, wherein said second carbon dioxide concentration is less than said first carbon dioxide concentration, and wherein said second carbon dioxide concentration ranges from at least 5 percent by weight to less than said first carbon dioxide concentration; and

separating said carbon dioxide from said ambient air/combustion effluent mixture, said separating comprising:

cooling said ambient air/combustion effluent mixture, thereby yielding a cooled mixture;

contacting said cooled mixture with a desiccant to remove at least a portion of said water from said cooled mixture, thereby yielding a cooled/dried mixture; and

contacting said cooled/dried mixture with a physisorption material to remove at least a portion of said carbon dioxide from said cooled/dried mixture.

11. The method of claim 10 wherein said gaseous mixture is landfill gas.

12. The method of claim 10 wherein said gaseous mixture comprises about 45 to about 55 percent by weight of said carbon dioxide and about 55 to about 45 percent by weight of said methane.

13. The method of claim 10 wherein said combusting step comprises passing said methane through an internal combustion engine.

14. The method of claim 10 wherein said combusting step comprises passing said gaseous mixture through an internal combustion engine.

15. The method of claim 10 wherein said physisorption material comprises a zeolite.

16. The method of claim 10 further comprising the step of separating said carbon dioxide from said gaseous mixture prior to said combusting step.

17. The method of claim 10 wherein said physisorption material is at a first temperature and said cooled/dried mixture is at a second temperature, and wherein said second temperature is at most 10 degrees Celsius warmer than said first temperature.

18. The method of claim 10 wherein said second carbon dioxide concentration ranges from at least 10 percent by weight to less than said first carbon dioxide concentration.

19. The method of claim 10 wherein said second carbon dioxide concentration ranges from at least 12 percent by weight to less than said first carbon dioxide concentration.