Hydrogen production with reduced carbon dioxide generation and complete capture

1. A method of reducing the carbon dioxide balance from a reformer furnace flue gas to a high pressure syngas exit water gas shift reaction unit, the method comprising the steps of:

a) providing a first gas mixture;

b) heating said first stream mixture to a first temperature, then introducing said heated first gas mixture into a pre-reforming chamber to produce pre-reformed mixture;

c) further heating said pre-reformed mixture in a primary reformer, thereby generating a second gas mixture comprising hydrogen, carbon monoxide, carbon dioxide, and a flue gas, wherein said primary reformer comprises a reformer furnace and tubes filled with catalyst, wherein the second gas mixture and/or the flue gas provides said heating for step b);

d) introducing said second gas mixture into at least one isothermal shift reactor, or a combination of high followed by a low temperature shift reactor, or a medium temperature shift reactor, thereby generating a third gas mixture;

e) introducing said third gas mixture into a PSA unit, wherein said third gas mixture is separated into a hydrogen enriched stream and a PSA tail gas stream;

f) introducing said PSA tail gas stream into a CPU system, wherein said PSA tail gas stream is separated into a carbon dioxide enriched stream, a hydrogen rich stream, and a residual stream; and

g) introducing said residual stream as fuel into the reformer furnace along with natural gas, a portion of the feed hydrocarbon stream, a portion of the hydrogen enriched stream, or any other external make-up fuel for the reformer furnace,

wherein step b) is repeated twice in a second pre-reforming chamber and a third pre-reforming chamber, for a total of three pre-reforming steps, such that the resulting temperature of the pre-reformed mixture is higher after each repetition,

wherein each pre-reforming chamber comprises a bed of catalyst, wherein an outlet gas from each pre-reformer is heated up in a coil in exchange with the second gas mixture and/or the flue gas before going to the next pre-reforming chamber,

wherein the flue gas is utilized for industrial purposes resulting in 100% recovery of the CO2 and no emission of nitrogen oxides from the primary reformer,

wherein the flue gas is contacted with hydrogen from the PSA unit and passed over a bed of catalyst to promote combustion.

2. The method of claim 1 , wherein said CPU comprises a compression purification unit, or a combination of CPU and membrane units.

3. The method of claim 1 , wherein the three beds of catalyst are stacked in one vessel with internal heads.

4. The method of claim 1 , wherein the carbon dioxide enriched stream represents greater than 80% of the overall CO2 generated in the primary reformer.

5. The method of claim 4 , wherein the carbon dioxide enriched stream represents greater than 90% of the overall CO2 generated in the primary reformer.

6. The method of claim 1 , wherein there is no steam exported from the primary reformer.

7. The method of claim 1 , wherein a portion of the hydrogen rich stream is recycled to the PSA unit.

8. The method of claim 1 , wherein a portion of the residual stream is recycled upstream of the first pre-reforming chamber.

9. The method of claim 1 , wherein a portion of the hydrogen rich stream is recycled to the PSA unit and a portion of the residual stream is recycled upstream of the first pre-reforming chamber.

10. The method of claim 1 , wherein the SMR furnace flue gas is compressed and used for Enhanced Oil Recovery.

11. The method of claim 10 , wherein the SMR Furnace Flue gas is dried to remove water by passing through a bed of adsorbent.

12. The method of claim 11 , wherein the Nitrogen+Argon composition of the flue gas downstream of the drier is greater than or equal to 95%.

13. The method of claim 1 , wherein the oxygen content of the flue gas downstream of the primary reformer is less than 0.1 mol %.

14. The method of claim 13 , further comprising the step of passing the flue gas through a drier comprising a bed of adsorbent to remove water from the flue gas.

15. The method of claim 14 , wherein the Nitrogen+Argon composition of the flue gas downstream of the drier is greater than or equal to 99%.

16. A method of reducing the carbon dioxide balance from a reformer furnace flue gas to a high pressure syngas exit water gas shift reaction unit, the method comprising the steps of:

a) providing a first gas mixture;

b) heating said first stream mixture to a first temperature, then introducing said heated first gas mixture into a pre-reforming chamber to produce, a pre-reformed mixture;

c) further heating said pre-reformed mixture in a primary reformer, thereby generating a second gas mixture comprising hydrogen, carbon monoxide, carbon dioxide, and a flue gas, wherein said primary reformer comprises a reformer furnace and tubes filled with catalyst, wherein the second gas mixture and/or the flue gas provides said heating for step b);

d) introducing said second gas mixture into at least one isothermal shift reactor, or a combination of high followed by a low temperature shift reactor, or a medium temperature shift reactor, thereby generating a third gas mixture;

e) introducing said third gas mixture into a PSA unit, wherein said third gas mixture is separated into a hydrogen enriched stream and a PSA tail gas stream;

f) introducing said PSA tail gas stream into a CPU system, wherein said PSA tail gas stream is separated into a carbon dioxide enriched stream, a hydrogen rich stream, and a residual stream; and

g) introducing said residual stream as fuel into the reformer furnace along with natural gas, a portion of the feed hydrocarbon stream, a portion of the hydrogen enriched stream, or any other external make-up fuel for the reformer furnace,

wherein step b) is repeated twice in a second pre-reforming chamber and a third pre-reforming chamber, for a total of three pre-reforming steps, such that the resulting temperature of the pre-reformed mixture is higher after each repetition,

wherein each pre-reforming chamber comprises a bed of catalyst, wherein an outlet gas from each pre-reformer is heated up in a coil in exchange with the second gas mixture and/or the flue gas before going to the next pre-reforming chamber,

wherein each pre-reforming chamber includes a bank of tubes filled with catalyst that are configured to be heated in counter-current contact with the flue gas,

wherein the carbon dioxide enriched stream represents greater than 85% of the overall CO2 generated in the primary reformer,

wherein the catalyst at the top of the tube include conventional pre-reforming catalyst and at the bottom of tube include typical main catalyst bed reforming catalyst,

wherein the transition between pre-reforming catalyst and main reforming catalyst is done through a series of progressively larger catalyst pellets.

17. The method of claim 16 , wherein the flue gas is utilized for industrial purposes resulting in 100% recovery of the CO2 and no emission of nitrogen oxides from the primary reformer.

18. The method of claim 17 , wherein the flue gas is compressed and used for Enhanced Oil Recovery.

19. The method of claim 18 , further comprising the step of passing the flue gas through a drier comprising a bed of adsorbent to remove water from the flue gas.

20. The method of claim 19 , wherein the Nitrogen+Argon composition of the flue gas downstream of the drier is greater than or equal to 95%.

21. The method of claim 1 , wherein the oxygen content of the flue gas downstream of the combustion zone is less than 0.1 mol %.

22. The method of claim 21 , further comprising the step of passing the flue gas through a drier comprising a bed of adsorbent to remove water from the flue gas.

23. The method of claim 22 , wherein the Nitrogen+Argon composition of the flue gas downstream of the drier is greater than or equal to 99%.

24. The method of claim 16 , wherein the carbon dioxide enriched stream represents greater than 95% of the overall CO2 generated in the primary reformer.

25. The method of claim 16 , wherein no steam is exported from the primary reformer.

26. The method of claim 16 , wherein a portion of the hydrogen rich stream is compressed and recycled to the PSA unit.

27. The method of claim 16 , wherein a portion of the residual stream is compressed and recycled upstream of the first pre-reforming chamber.

28. The method of claim 16 , wherein a portion of the hydrogen rich stream is recycled to the PSA unit and a portion of the residual stream is recycled upstream of the first pre-reforming chamber.

29. The method of claim 16 , wherein each zone of catalyst is at least 3 inches deep.

30. The method of claim 16 , wherein the process gas from the exit of the pre-reforming tube is passed through two helical shaped tubes back up the pre-reformer tube.

31. The method of claim 30 , wherein a portion of the heat for the reforming reaction in said tubes is provided by exchange with the exit gas through the helical shaped tubes.

32. The method of claim 31 , wherein the temperature of the exit gas from the top of the helical tubes is between 500 and 1300 Degrees F.

33. The method of claim 31 , wherein the temperature of the exit gas from the top of the helical tubes is between 1200 and 1300 Degrees F.

34. A method of reducing the carbon dioxide balance from a reformer furnace flue gas to a high pressure syngas exit water gas shift reaction unit, the method comprising the steps of:

a) providing a first gas mixture;

b) heating said first stream mixture to a first temperature, then introducing said heated first gas mixture into a pre-reforming chamber to produce, a pre-reformed mixture;

c) further heating said pre-reformed mixture in a primary reformer, thereby generating a second gas mixture comprising hydrogen, carbon monoxide, carbon dioxide, and a flue gas, wherein said primary reformer comprises a reformer furnace and tubes filled with catalyst, wherein the second gas mixture and/or the flue gas provides said heating for step b);

d) introducing said second gas mixture into at least one isothermal shift reactor, or a combination of high followed by a low temperature shift reactor, or a medium temperature shift reactor, thereby generating a third gas mixture;

e) introducing said third gas mixture into a PSA unit, wherein said third gas mixture is separated into a hydrogen enriched stream and a PSA tail gas stream;

f) introducing said PSA tail gas stream into a CPU system, wherein said PSA tail gas stream is separated into a carbon dioxide enriched stream, a hydrogen rich stream, and a residual stream; and

g) introducing said residual stream as fuel into the reformer furnace along with natural gas, a portion of the feed hydrocarbon stream, a portion of the hydrogen enriched stream, or any other external make-up fuel for the reformer furnace,

wherein step b) is repeated twice in a second pre-reforming chamber and a third pre-reforming chamber, for a total of three pre-reforming steps, such that the resulting temperature of the pre-reformed mixture is higher after each repetition,

wherein each pre-reforming chamber comprises a bed of catalyst, wherein an outlet gas from each pre-reformer is heated up in a coil in exchange with the second gas mixture and/or the flue gas before going to the next pre-reforming chamber,

wherein a process gas from the exit of a reforming tube is passed through two helical shaped tubes back up a pre-reformer tube,

wherein the flue gas from the primary reformer is utilized for industrial purposes resulting in 100% recovery of the CO2 and no emission of nitrogen oxides from the primary reformer,

wherein the flue gas is contacted with hydrogen from the PSA and passed over a bed of catalyst to promote combustion.

35. The method of claim 34 , wherein a portion of the heat for the reforming reaction in said tubes is provided by exchange with the exit gas through the helical shaped tubes.

36. The method of claim 34 , wherein flue gas is compressed and used for Enhanced Oil Recovery.

37. The method of claim 36 , further comprising the step of passing the flue gas through a drier comprising a bed of adsorbent to remove water from the flue gas.

38. The method of claim 37 , wherein the Nitrogen+Argon composition of the flue gas downstream of the drier is greater than or equal to 95%.

39. The method of claim 34 , wherein the oxygen content of the flue gas downstream of the combustion zone is less than 0.1 mol %.

40. The method of claim 39 , further comprising the step of passing the flue gas through a drier comprising a bed of adsorbent to remove water from the flue gas.

41. The method of claim 40 , wherein the Nitrogen+Argon composition of the flue gas downstream of the drier is greater than or equal to 97%.

42. The method of claim 34 , wherein the carbon dioxide enriched stream represents greater than 80% of the overall CO2 generated in the primary reformer.

43. The method of claim 42 , wherein the carbon dioxide enriched stream represents greater than 90% of the overall CO2 generated in the primary reformer.

44. The method of claim 34 , wherein there is no steam exported from the primary reformer.

45. The method of claim 34 , wherein a portion of the hydrogen rich stream is recycled to the PSAunit.

46. The method of claim 34 , wherein a portion of the residual stream is recycled upstream of the first pre-reforming chamber.

47. The method of claim 34 , wherein a portion of the hydrogen rich stream is recycled to the PSA unit and a portion of the residual stream is recycled upstream of the first pre-reforming chamber.