ELECTRIC REACTION TECHNOLOGY FOR FUELS PROCESSING

Abstract

A method and apparatus for producing hydrogen is disclosed wherein a hydrocarbon gas is fed into an electric reaction technology system to decompose the hydrocarbon gas to hydrogen gas and carbon solids. The electric reaction technology system comprises one or more heating zones, wherein each heating zone comprises one or more heating stations and each heating station comprises one or more heating screens followed by a final near-equilibrium attainment zone without additional heat input. After passing the hydrogen gas through the electric reaction technology system the hydrogen gas and any remaining carbon solids and hydrocarbon gas are cooled. The hydrogen gas and any remaining carbon solids and hydrocarbon gas flow through a scrubber, filter, drier or other phase separation system to remove substantially all of the carbon, leaving hydrogen product. The electric reaction technology system can also be used to pyrolyze hydrocarbons.

Description

DESCRIPTION OF THE DRAWINGS

The invention is best understood from the following detailed description when read with the accompanying drawings.

FIG. 1 depicts a stagewise hydrogen production system according to an illustrative embodiment of the invention.

FIG. 2 is a graph showing equilibrium and operating curves for a stagewise hydrogen production system according to an illustrative embodiment of the invention.

FIG. 3 depicts a hydrogen production system having a recycle configuration according to an illustrative embodiment of the invention.

FIG. 4 is a graph showing equilibrium and operating curves for a hydrogen production system having a recycle configuration according to an illustrative embodiment of the invention.

FIG. 5 depicts a single pass hydrogen production system according to an illustrative embodiment of the invention.

FIG. 6 is a graph showing equilibrium and operating curves for a hydrogen production system having a single pass configuration according to an illustrative embodiment of the invention.

Claims

1. A method for producing hydrogen comprising: feeding a hydrocarbon gas into an electric reaction technology system to decompose the hydrocarbon gas to hydrogen gas and carbon solids, the electric reaction technology system comprising one or more heating zones, wherein each heating zone comprises one or more heating stations and each heating station comprises one or more heating screens;after passing the hydrogen gas through the electric reaction technology system, cooling the hydrogen gas and any remaining carbon solids and hydrocarbon gas;flowing the hydrogen gas and any remaining carbon solids and hydrocarbon gas through a phase separation system to remove substantially all of the carbon; andflowing the hydrogen and any remaining carbon solids and hydrocarbon gas out of the system.

2. The method of claim 1 wherein the temperature of the hydrogen and any remaining carbon and hydrocarbons leaving the electric reaction technology system is in the range of about 2000° F. to about 2700° F.

3. The method of claim 1 further comprising utilizing heat generated from the electric reaction technology system to heat the incoming hydrocarbon gas feed.

4. The method of claim 3 wherein the hydrocarbon gas feed is heated by the heat generated from the electric reaction technology system to a temperature in the range of about 800° F. to about 1200° F.

5. The method of claim 3 wherein the heat generated from the electric reaction technology system is utilized to heat the incoming hydrocarbon gas feed by: flowing the hydrocarbon gas into a heat exchanger; andflowing the heated hydrogen gas and any remaining carbon solids and hydrocarbon gas through the heat exchanger to heat additional incoming hydrocarbon gas.

6. The method of claim 1 further comprising: flowing the heated hydrogen gas and carbon solids through a carbon removal component after each heating zone to remove some or all of the carbon solids;

7. The method of claim 1 further comprising: pre-heating the hydrocarbon gas flow prior to feeding it into the electric reaction technology system or heat exchanger.

8. The method of claim 7 wherein the temperature increase of the hydrocarbon gas flow from the pre-heating step is in the range of about 250 F° to about 600 F°.

9. The method of claim 1 further comprising: adding water to the hydrogen gas and any remaining carbon solids and hydrocarbon gas in the phase separation system to create a slurry containing substantially all of the carbon.

10. The method of claim 1 further comprising: recycling at least a portion of the heated hydrogen gas and any remaining carbon solids and hydrocarbon gas exiting the heat exchanger into the hydrocarbon gas flow.

11. The method of claim 10 wherein the ratio of recycled hydrogen to non-recycled hydrogen is in the range of about 2:1 to about 4:1.

12. The method of claim 10 comprising: flowing the hydrogen gas to be recycled through a recycle compressor.

13. The method of claim 1 further comprising flowing the heated hydrogen gas and any remaining carbon solids and hydrocarbon gas through a quench system after exiting the electric reaction technology system and prior to entering the phase separation system.

14. The method of claim 1 further comprising powering the system with electricity generated by wind.

15. The method of claim 1 wherein the hydrocarbon is methane.

16. The method of claim 1 wherein one or more heating stations delivers a different heating duty to the system.

17. The method of claim 1 wherein four zones are provided.

18. The method of claim 1 wherein at least one zone has four screen stations.

19. The method of claim 1 wherein the exit temperature at each heating zone is at least about 50 F° greater than the equilibrium temperature at the corresponding exit concentration of hydrogen.

20. The method of claim 1 wherein the electric reaction technology system is disposed in a substantially vertical position with respect to the level ground.

21. The method of claim 1 wherein the electric reaction technology system is disposed in a substantially horizontal position with respect to the level ground.

22. The method of claim 1 wherein the spacing between heating screen stations increases in the gas flow direction.

23. The method of claim 1 wherein the heat duty delivered by each heating station is substantially equal.

24. The method of claim 1 wherein the heat duty delivered by each heating screen station is substantially constant within each zone.

25. The method of claim 24 wherein the heat duty delivered by each subsequent zone decreases.

26. The method of claim 1 wherein the heat duty delivered by all zones is constant.

27. The method of claim 1 wherein the heating screen station spacing varies continuously after the first zone to maintain substantially isothermal conditions.

28. The method of claim 1 wherein the temperature varies between heating screen zones.

29. The method of claim 1 wherein the difference between the temperature of the flow entering a heating screen station and the temperature of the flow exiting the heating station is in the range of about 125 F° to about 175 F°.

30. The method of claim 1 further comprising one or more near-equilibrium attainment zones following each electric reaction technology unit.

31. The method of claim 1 further comprising: utilizing the product from the electric reaction technology system as a heat source for a solid oxide fuel cell.

32. A method comprising: generating carbon according to claim 1;utilizing the generated carbon as a component of a molten carbonate fuel cell.utilizing the product exited from the electric reaction technology system as a heat source for a solid oxide fuel cell.

33. The method of claim 1 wherein hydrogen is added to the hydrocarbon gas prior to entrance to the electric reaction technology system.

34. The method of claim 1 wherein the residence time increases for each heating station.

35. The method of claim 1 wherein the residence time decreases for each heating station.

36. The method of claim 1 wherein the residence time increases for each heating station in a first section of the reaction technology system and then decreases for the remaining heating station(s).

37. The method of claim, 1 wherein further comprising: choosing residence times to maintain substantially isothermal conditions.

38. A hydrogen production system comprising: an electric reaction technology system having one or more heating zones, wherein each heating zone comprises one or more heating stations and each heating station comprises one or more heating screens followed by a final near-equilibrium attainment zone without additional heat input;an inlet into a first of the one or more heating zones for input of a gas from which hydrogen will be formed;a finishing station for cooling and removal of carbon solids; andan outlet for output of the hydrogen gas.

39. The system of claim 38 further comprising: a heat exchanger disposed after the heating zones to utilize heat from the electric reaction technology system to heat the incoming gas.

40. The system of claim 38 further comprising a carbon removal component after each heating zone to remove some or all of the carbon solids;

41. The system of claim 38 further comprising a pre-heater disposed after the inlet and before the first heating zone.

42. The system of claim 38 further comprising a recycling mechanism to recycle at least a portion of the heated hydrogen gas and any remaining carbon solids and hydrocarbon gas exiting the heat exchanger into the hydrocarbon gas flow.

43. The system of claim 42 further comprising a recycle compressor disposed within the system such that recycled hydrogen passes through it prior to mixing with the input gas.

44. The system of claim 38 further comprising a wind-generated electricity source.

45. The system of claim 38 wherein one or more heating stations delivers a different heating duty to the system.

46. The system of claim 38 comprising four heating zones.

47. The system of claim 38 comprising four heating screens for at least one zone.

48. The system of claim 38 wherein the electric reaction technology system is disposed in a substantially vertical position with respect to the level ground.

49. The system of claim 38 wherein the spacing between heating screen stations increases in the gas flow direction.

50. The system of claim 38 wherein the heat duty delivered by each heating screen station is substantially equal.

51. The system of claim 38 wherein the heat delivered by each heating screen station is substantially constant within each zone.

52. The system of claim 38 wherein the heat duty delivered by each subsequent zone decreases.

53. The system of claim 38 wherein the heating screen station spacing varies continuously after the first zone to maintain substantially isothermal conditions by controlling reaction rates and volumes.

54. The system of claim 38 wherein the temperature varies between heating screen zones.

55. The system of claim 38 comprising a second inlet to introduce a second gas into the first gas stream prior to entering the first zone.

56. A pyrolysis method comprising: feeding a hydrocarbon gas into an electric reaction technology system to pyrolyze the hydrocarbon gas to produce cracked gas products, the electric reaction technology system comprising one or more heating zones, wherein each heating zone comprises one or more heating stations and each heating station comprises one or more heating screens.quenching the cracked gas products; andseparating the cracked gas products.

57. The method of claim 56 wherein ethylene is separated from the cracked products.

58. The method of claim 56 wherein ethylene is separated from the cracked products.

59. The method of claim 56 wherein acetylene is separated from the cracked products.

60. The method of claim 56 wherein, after separation of the cracked gas products, hydrogen is recycled into the process.

61. The method of claim 56 wherein the hydrocarbon feed gas comprises one or more hydrocarbons that can be vaporized.

62. The method of claim 56 wherein the hydrocarbon feed gas is selected from the group consisting of ethane, propane, butane, naphthas and gas oils.

63. The method of claim 56 wherein steam is added to the feedstock before it enters the Electric Reaction Technology System.