Efficient low rank coal gasification, combustion, and processing systems and methods

• US 9,181,509 B2
• Filed: 05/24/2010
• Issued: 11/10/2015
• Est. Priority Date: 05/22/2009
• Status: Active Grant

• Current Assignee: Western Research Institute
• Original Assignee: The University of Wyoming Research Corporation
• Inventors: Bland, Alan E., Sellakumar, Kumar Muthusami, Newcomer, Jesse D.
• Primary Examiner(s): Gravini, Stephen M
• Application Number:
  US13/321,527
• Publication Number:
  US 20120056431A1
• Time in Patent Office: 1,996 Days
• Field of Search: 343/80, 343/81, 344/13, 344/97, 423/215.5, 604/07, 607/81, 29/52, 296/235, 298/90, 481/97.R, 482/10, 122/22
• US Class Current: 1/1
• CPC Class Codes: C10J 2300/0903 Feed preparation
• CPC Class Codes: C10J 2300/0909 Drying
• CPC Class Codes: C10J 2300/093 Coal
• CPC Class Codes: C10J 2300/0969 Carbon dioxide
• CPC Class Codes: C10J 2300/1643 Conversion of synthesis gas to energy
• CPC Class Codes: C10J 2300/1656 Conversion of synthesis gas to chemicals
• CPC Class Codes: C10J 2300/1815 for carbon dioxide
• CPC Class Codes: C10J 3/02 Fixed-bed gasification of lump fuel
• CPC Class Codes: C10J 3/84 with means for removing dust or tar from the gas
• CPC Class Codes: C10L 5/366 Powders
• CPC Class Codes: C10L 9/08 by heat treatments, e.g. calcining
• CPC Class Codes: Y02E 20/16 Combined cycle power plant [CCPP], or combined cycle gas turbine [CCGT]
• CPC Class Codes: Y02E 20/18 Integrated gasification combined cycle [IGCC], e.g. combined with carbon capture and storage [CCS]
• CPC Class Codes: Y10T 29/49229 Prime mover or fluid pump making

Abstract

Efficient coal pre-processing systems (69) integrated with gasification, oxy-combustion, and power plant systems include a drying chamber (28), a volatile metal removal chamber (30), recirculated gases, including recycled carbon dioxide (21), nitrogen (6), and gaseous exhaust (60) for increasing the efficiencies and lowering emissions in various coal processing systems.

Claims

1. A method for retrofitting a power plant facility comprising the steps of:

supplying wet coal in a power plant system assembly;

feeding said wet coal into a drying chamber of said power plant system assembly;

recycling a first supply of recycled non-air to said at least one chamber;

recycled pre-process drying said wet coal with said first supply of recycled non-air in a drying chamber for a first amount of time to create a substantially dried coal having a coal temperature of up to about 300°

F.;

transferring said substantially dried coal to a separate volatile metal removal chamber;

recycling a second supply of recycled non-air to said substantially dried coal to said separate volatile metal removal chamber;

recycled pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature up to about 600°

F.;

generating a volatile metal removal effluent gas stream from said separate volatile metal removal chamber;

cooling said volatile metal reduced dried coal;

transferring said volatile metal reduced dried coal to a boiler assembly;

air fired combusting said volatile metal reduced dried coal in said boiler assembly;

producing a gaseous exhaust composed predominantly of carbon dioxide and nitrogen from said boiler assembly;

heating boiler water in said boiler assembly with heat from said combusted volatile metal reduced dried coal to create steam;

driving a turbine with said steam; and

driving at least one generator responsive to said turbine with said steam to produce electricity from said power plant system assembly,

wherein said steps of feeding said wet coal into a drying chamber of said power plant system assembly, recycling a first supply of recycled non-air to said at least one chamber;

recycled pre-process drying said wet coal with said first supply of recycled non-air in a drying chamber for a first amount of time to create a substantially dried coal having a coal temperature of up to about 300°

F.;

transferring said substantially dried coal to a separate volatile metal removal chamber;

recycling a second supply of recycled non-air to said substantially dried coal to said separate volatile metal removal chamber;

recycled pre-process removing volatile metal from said substantially dried coal in said separate volatile metal removal chamber with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature up to about 600°

F.;

generating a volatile metal removal effluent gas stream from said separate volatile metal removal chamber; and

cooling said volatile metal reduced dried coal are each retrofitted into an existing power plant system assembly.

2. A method for retrofitting a power plant facility according to claim 1 wherein said recycled non-air is selected from a group consisting of flue gas, inert gas, heated gas, carbon dioxide, nitrogen, steam, and any combination thereof.

3. A method for retrofitting a power plant facility according to claim 1 and further comprising the step of recycling said first supply of recycled non-air and said second supply of recycled non-air comes from a same source within said power plant system assembly.

4. A method for retrofitting a power plant facility according to claim 3 wherein said source comprises a recycled gaseous exhaust.

5. A method for retrofitting a power plant facility according to claim 1 and further comprising the step of recycling said first supply of recycled non-air and said second supply of recycled non-air comes from different sources within said power plant system assembly.

6. A method for retrofitting a power plant facility according to claim 5 wherein said different sources are selected from a group consisting of recycled gaseous exhaust, effluent gas from said separate volatile metal removal chamber, effluent gas from said drying chamber, a heated gas, steam, an inert gas, carbon dioxide, nitrogen, steam, and any combination thereof.

7. A method for retrofitting a power plant facility according to claim 1 and further comprising the step of converting said step of air fired combusting to an oxygen-fired combusting system.

8. A method for retrofitting a power plant facility according to claim 7 wherein said step of converting to an oxygen-fired combusting system comprises the steps of adding an air separation unit to said power plant system assembly and supplying oxygen to said boiler assembly.

9. A method for retrofitting a power plant facility according to claim 1 wherein said step of recycled pre-process drying said wet coal with said first supply of recycled non-air comprises the step of providing said substantially dried coal selected from a group consisting of at least about 90% dry, at least about 91% dry, at least about 92% dry, at least about 93% dry, at least about 94% dry, at least about 95% dry, at least about 96% dry, at least about 97% dry, at least about 98% dry, at least about 99% dry, and about 100% dry.

10. A method for retrofitting a power plant facility according to claim 1 wherein said steps of recycling said first supply of recycled non-air to said at least one chamber and said step of recycling a second supply of recycled non-air to said substantially dried coal to said separate volatile metal removal chamber comprises the step of recycling a first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber.

11. A method for retrofitting a power plant facility according to claim 10 wherein said step of recycling said first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber comprises the step of heating said recycled non-air with hot gaseous exhaust located in said system selected from a group consisting of a furnace, a boiler convective pass, and a downstream flue gas location.

12. A method for retrofitting a power plant facility according to claim 1 wherein said drying chamber is selected from a group consisting of a fluidized bed dryer, a moving bed dryer, and a fixed bed dryer.

13. A method for retrofitting a power plant facility according to claim 1 wherein said first amount of time is selected from a group consisting of at least about 2 minutes, up to about 30 minutes, between about 5 minutes and about 30 minutes, between about 8 minutes and 16 minutes, and up to about 16 minutes.

14. A method for retrofitting a power plant facility according to claim 1 wherein said second amount of time is selected from a group consisting of at least about 2 minutes, up to about 30 minutes, between about 5 minutes and about 30 minutes, between about 8 minutes and 16 minutes, and up to about 16 minutes.

15. A method for retrofitting a power plant facility according to claim 1 wherein said step of recycled pre-process removing volatile metals from said substantially dried coal comprises the step of providing said volatile metal reduced dried coal having a mercury removal selected from a group consisting of between about 50% and about 87%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, and about 100%.

16. A method for retrofitting a power plant facility according to claim 1 wherein said step of recycled pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber comprises the step of removing volatile metals from said coal, said volatile metals selected from a group consisting of arsenic, selenium, cadmium, lead, and mercury.

17. A method for retrofitting a power plant facility according to claim 1 and further comprising the steps of directing said volatile metals removal effluent gas from said separate volatile metal removal chamber to said drying chamber;

and using said volatile metals removal effluent gas to dry said coal.

21. A method for retrofitting a power plant facility according to claim 7 wherein said oxygen-fired combustion system comprises an oxygen content selected from a group consisting of between about 20.89% and about 35% in volume of the oxidant supply stream.

22. A method for retrofitting a power plant facility according to claim 10 wherein said step of recycling said first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber comprises the step of heating said first supply and second supply of recycled non-air from a single heat source.

23. A method for retrofitting a power plant facility according to claim 10 wherein said step of recycling said first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber comprises the step of heating said first supply of recycled non-air from at least two heat sources.

24. A method for retrofitting a power plant facility according to claim 1 wherein said step of recycled pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber occurs after said step of recycled pre-process drying said wet coal with said first supply of recycled non-air.

25. A method for retrofitting a power plant facility according to claim 1 wherein said step of recycled pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature up to about 600°

F. comprises the step of recycled pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature between about 275°

F. and about 600°

F.

26. A method for retrofitting a power plant facility according to claim 17 wherein said volatile metals removal effluent gas is selected from a group consisting of nitrogen, carbon dioxide, gaseous exhaust, steam, and any combination thereof.

38. An efficient method for oxy-combustion processing according to claim 24 wherein said step of pre-process removing volatile metals from said substantially dried coal comprises the step of removing volatile metals from said coal, said volatile metals selected from a group consisting of arsenic, selenium, cadmium, lead, and mercury.

100. A method according to claim 1 wherein said wet coal is selected from a group consisting of bituminous coal, subbituminous coal, lignite, biomass, coal-biomass blends, and any combination thereof.

104. A method according to claim 1 wherein said wet coal comprises a moisture content selected from a group consisting of about 8%, about 20%, about 28%, about 38%, up to about 60%, up to about 50%, up to about 20%, up to about 25%, up to about 28%, up to about 38%, greater than about 20%, and greater than about 60%.

108. A method according to claim 1 and further comprising the step of recovering water in said system assembly.

112. A method according to claim 108 and further comprising the step treating said water.

116. A method according to claim 108 and further comprising the step of recycling said water in at least part of said power plant system assembly selected from a group consisting of a sulfur dioxide emissions scrubber, a boiler feedwater makeup, a cooling tower makeup and any combination thereof.

120. A method according to claim 12 wherein said fluidized dryer bed is configured to remove up to about 100% of the moisture of said wet coal.

18. An efficient method for oxy-combustion processing comprising the steps of:

supplying wet coal in an oxy-combustion system assembly;

feeding said wet coal into at least one chamber of said oxy-combustion system assembly;

pre-process drying said wet coal in said at least one chamber to create a substantially dried coal having a coal temperature of up to about 300°

F.;

pre-process removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal having a coal temperature of up to about 600°

F.;

cooling said volatile metal reduced dried coal;

transferring said volatile metal reduced dried coal to a boiler assembly;

oxygen-fired combusting said volatile metal reduced dried coal in said boiler assembly;

producing a gaseous exhaust composed predominantly of carbon dioxide and water from said boiler assembly;

heating boiler water in said boiler assembly with heat from said combusted volatile metal reduced dried coal to create steam;

driving a turbine with said steam; and

driving at least one generator responsive to said turbine with said steam to produce electricity.

27. An efficient method for oxy-combustion processing according to claim 18 wherein said step of pre-process drying said wet coal comprises the step of providing said substantially dried coal selected from a group consisting of at least about 90% dry, at least about 91% dry, at least about 92% dry, at least about 93% dry, at least about 94% dry, at least about 95% dry, at least about 96% dry, at least about 97% dry, at least about 98% dry, at least about 99% dry, and about 100% dry.

28. An efficient method for oxy-combustion processing according to claim 18 wherein said step of pre-process drying said wet coal comprises the step of non-air pre-process drying said wet coal with recycled non-air.

29. An efficient method for oxy-combustion processing according to claim 18 and further comprising the step of recycling a first supply of recycled non-air to said at least one chamber.

30. An efficient method Ibr oxy-eombustion processing according to claim 18 wherein said step or recycling said first supply of recycled non-air comprises the step of drying said wet coal for a first amount of time.

31. An efficient method for oxy-combustion processing according to claim 18 wherein said step of pre-process removing volatile metals from said substantially dried coal comprises the step of pre-process removing volatile metals from said substantially dried coal in a separate volatile metal removal chamber.

32. An efficient method for oxy-combustion processing according to claim 18 wherein said step of pre-process removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal having a coal temperature of up to about 600°

F. comprises the step of providing said volatile metal reduced dried coal having a mercury removal selected from a group consisting of between about 50% and about 87%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, and about 100%.

33. An efficient method for oxy-combustion processing according to claim 18 wherein said step of pre-process removing volatile metals from said substantially dried coal comprises the step of pre-process removing volatile metals from said substantially dried coal with recycled non-air.

34. An efficient method for oxy-combustion processing according to claim 29 wherein said step of recycling said supply of recycled non-air comprises the step of recycling a supply of heated non-air to said chamber.

35. An efficient method for oxy-combustion processing according to claim 33 wherein said step of pre-process removing volatile metals from said substantially dried coal comprises the step of pre-process removing volatile metals from said substantially dried coal for a second amount of time.

36. An efficient method for oxy-combustion processing according to claim 30 wherein said first amount of time is selected from a group consisting of at least about 2 minutes, up to about 30 minutes, between about 5 minutes and about 30 minutes, between about 8 minutes and 16 minutes, and up to about 16 minutes.

37. An efficient method for oxy-combustion processing according to claim 35 wherein said second amount of time is selected from a group consisting of at least about 2 minutes, up to about 30 minutes, between about 5 minutes and about 30 minutes, between about 8 minutes and 16 minutes, and up to about 16 minutes.

39. An efficient method for oxy-combustion processing according to claim 31 and further comprising the step of generating a volatile metals removal effluent gas stream from said separate volatile metal removal chamber.

40. An efficient method for oxy-combustion processing according to claim 39 and further comprising the steps of directing said volatile metals removal effluent gas from said separate volatile metal removal chamber to said drying chamber;

and using said volatile metals removal effluent gas to dry said coal.

41. An efficient method for oxy-combustion processing according to claim 40 wherein said volatile metals removal effluent gas is selected from a group consisting of nitrogen, carbon dioxide, steam, gaseous exhaust, and any combination thereof.

101. A method according to claim 18 wherein said wet coal is selected from a group consisting of bituminous coal, subbituminous coal, lignite, biomass, coal-biomass blends, and any combination thereof.

105. A method according to claim 18 wherein said wet coal comprises a moisture content selected from a group consisting of about 8%, about 20%, about 28%, about 38%, up to about 60%, up to about 50%, up to about 20%, up to about 25%, up to about 28%, up to about 38%, greater than about 20%, and greater than about 60%.

109. A method according to claim 18 and further comprising the step of recovering water in said system assembly.

113. A method according to claim 109 and further comprising the step treating said water.

117. A method according to claim 109 and further comprising the step of recycling said water in at least part of said power plant system assembly selected from a group consisting of a sulfur dioxide emissions scrubber, a boiler feedwater makeup, a cooling tower makeup and any combination thereof.

19. An efficient method for coal gasification comprising the steps of:

supplying wet coal in a coal gasification system assembly;

feeding said wet coal into at least one chamber of said coal gasification system assembly;

drying said wet coal in said at least one chamber to create a substantially dried coal having a coal temperature of up to about 300°

F.;

removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal having a coal temperature of up to about 600°

F.;

cooling said volatile metal reduced dried coal;

transferring said volatile metal reduced dried coal to a gasifier;

producing syngas from said volatile metal reduced dried coal in said gasifier;

cooling said syngas produced from said gasifier;

filtering said syngas from particulate matter;

separating carbon dioxide from said syngas to create a fuel gas supply and a downstream carbon dioxide supply; and

recirculating said downstream carbon dioxide back into at least part of said coal gasification system assembly.

42. An efficient method for coal gasification according to claim 19 and further comprising the step of using said fuel gas supply to produce electricity.

43. An efficient method for coal gasification according to claim 19 and further comprising the step of using said fuel gas supply to produce chemicals.

44. An efficient method for coal gasification according to claim 19 wherein said step of recirculating said downstream carbon dioxide back into at least part of said coal gasification system assembly comprises the step of heating said downstream carbon dioxide with a heat exchanger and directing said carbon dioxide to said at least part of said coal gasification system assembly.

45. An efficient method for coal gasification according to claim 19 wherein said step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal comprises the step of removing up to about 87% of mercury from said coal in said at least one chamber.

46. An efficient method for coal gasification according to claim 19 and further comprising the step of removing a total of up to about 90% of mercury from said coal in said coal gasification system assembly.

47. An efficient method for coal gasification according to claim 19 wherein said part of said coal gasification system assembly is selected from a group consisting of at least one chamber, a drying chamber, a volatile metal removal chamber, a particulate separation device, a barrier filter, a cyclone, a gasifier, coal transport system, a water-gas-shift reactor, a syngas cleanup system, a gas turbine, a heat recovery steam generator system, and a syngas cooler.

48. An efficient method for coal gasification according to claim 19 wherein said step of recirculating said downstream carbon dioxide back into at least part of said coal gasification system assembly comprises the step of reacting said downstream carbon dioxide in gasification reactions of said gasification system assembly.

49. An efficient method for coal gasification according to claim 19 wherein said step of recirculating said downstream carbon dioxide back into at least part of said coal gasification system assembly comprises the step of using said downstream carbon dioxide as a heat carrier in at least part of said gasification system assembly.

50. An efficient method for coal gasification according to claim 19 wherein said step of recirculating said downstream carbon dioxide back into at least part of said coal gasification system assembly comprises the step of using said downstream carbon dioxide as a coal transporter in at least part of said gasification system assembly.

51. An efficient method for coal gasification according to claim 44 wherein said step of heating said downstream carbon dioxide comprises the step of heating said downstream carbon dioxide with a heater selected from a group consisting of heat exchangers in the syngas cooler, water-gas-shift reactor, syngas cleanup system, gas turbine, heat recovery steam generator system, and any combination thereof.

52. An efficient method for coal gasification according to claim 19 and further comprising the step of providing an air separation unit to create an output of oxygen and nitrogen from an air input.

53. An efficient method for coal gasification according to claim 52 and further comprising the step of directing said oxygen output to said gasifier.

54. An efficient method for coal gasification according to claim 52 and further comprising the step of recirculating said nitrogen within said coal gasification system assembly.

55. An efficient method for coal gasification according to claim 54 wherein said step of recirculating said nitrogen within said coal gasification system assembly comprises the step of recirculating to at least part of said coal gasification system assembly selected from a group consisting of at least one chamber, a drying chamber, a volatile metal removal chamber, a high temperature volatile metals scrubber, a particulate separation device, barrier filter, a cyclone, a gas turbine, and any combination thereof.

56. An efficient method for coal gasification according to claim 54 and further comprising the step of heating said recirculated nitrogen.

57. An efficient method for coal gasification according to claim 56 wherein said step of heating said recirculated nitrogen comprises the step of heating said nitrogen to between about 500°

F. and about 900°

F.

58. An efficient method for coal gasification according to claim 56 wherein said step of heating said recirculated nitrogen comprises the step of heating said nitrogen in at least part of said coal gasification system assembly with heat exchangers selected from a group consisting of a syngas cooler, a high temperature volatile metals scrubber, a water gas shift reactor, syngas cleanup system, gas turbine, heat recovery steam generator system, and any combination thereof.

59. An efficient method for coal gasification according to claim 19 wherein said step of feeding said wet coal into at least one chamber of said coal gasification system assembly comprises the step of feeding said wet coal into a drying chamber of said coal gasification system assembly.

60. An efficient method for coal gasification according to claim 19 wherein said step of drying said wet coal in said at least one chamber to create a substantially dried coal comprises the step of providing said substantially dried coal selected from a group consisting of at least about 90% dry, at least about 91% dry, at least about 92% dry, at least about 93% dry, at least about 94% dry, at least about 95% dry, at least about 96% dry, at least about 97% dry, at least about 98% dry, at least about 99% dry, and about 100% dry.

61. An efficient method for coal gasification according to claim 19 wherein said step of drying said wet coal in said at least one chamber to create a substantially dried coal comprises the step of pre-process drying said wet coal with recycled non-air.

62. An efficient method for coal gasification according to claim 19 and further comprising the step of recycling a first supply of recycled non-air to said at least one chamber.

63. An efficient method for coal gasification according to claim 19 wherein said step of drying said wet coal in said at least one chamber to create a substantially dried coal comprises the step of drying said wet coal for a first amount of time.

64. An efficient method for coal gasification according to claim 19 wherein said at least one chamber comprises a fluidized bed.

65. An efficient method for coal gasification according to claim 59 wherein said drying chamber is selected from a group consisting of a fluidized bed dryer, a moving bed dryer, and a fixed dryer bed.

66. An efficient method for coal gasification according to claim 19 wherein said step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal comprises the step of removing volatile metals from said substantially dried coal in a separate volatile metal removal chamber to create a volatile metal reduced dried coal.

67. An efficient method for coal gasification according to claim 19 wherein said step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal having a coal temperature of up to about 600°

F. comprises the step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal having a coal temperature of between about 275°

F. and about 600°

F.

68. An efficient method for coal gasification according to claim 19 wherein said step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal comprises the step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal with recycled non-air.

69. An efficient method for coal gasification according to claim 66 and further comprising the step of recycling a second supply of recycled non-air to said separate volatile metal removal chamber.

70. An efficient method for coal gasification according to claim 19 wherein said step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal comprises the step of heating said substantially dried coal for a second amount of time.

71. An efficient method for coal gasification according to claim 62 wherein said step of recycling said supply of recycled non-air comprises the step of recycling a supply of heated non-air to said chamber.

72. An efficient method for coal gasification according to claim 71 wherein said step of recycling a supply of heated non-air comprises the step of heating said recycled non-air from a single heat source.

73. An efficient method for coal gasification according to claim 71 wherein said step of recycling a supply of heated non-air comprises the step of heating said recycled non-air from at least two heat sources.

74. An efficient method for coal gasification according to claim 71 wherein said step of recycling a supply of heated non-air to said chamber comprises the step of heating said recycled non-air with a heat source selected from a group consisting of heat from a gasifier, a syngas cooler, gas turbine exhaust, water gas shift reactor, heat recovery steam generator system, and any combination thereof.

75. An efficient method for coal gasification according to claim 19 wherein said step of removing volatile metals from said substantially dried coal in said at least one chamber to create a volatile metal reduced dried coal comprises the step of removing volatile metals from said coal, said volatile metals selected from a group consisting of arsenic, selenium, cadmium, lead, and mercury.

76. An efficient method for coal gasification according to claim 66 and further comprising the step of generating a volatile metal effluent gas stream from said separate volatile metal removal chamber.

77. An efficient method for coal gasification according to claim 76 and further comprising the step of directing said effluent gas stream from said separate volatile metal removal chamber to a drying chamber;

and using said effluent gas stream from said separate volatile metal removal chamber to dry said coal in said drying chamber.

78. An efficient method for coal gasification according to claim 77 wherein said volatile metals removal effluent gas is selected from a group consisting of nitrogen, carbon dioxide, gaseous exhaust, steam, and any combination thereof.

79. An efficient method for coal gasification according to claim 19 and further comprising the step of cleaning said particulate filtered syngas to remove gaseous species of sulfur and acid gases.

80. An efficient method for coal gasification according to claim 19 and further comprising the step of capturing sulfur in said coal gasification system assembly.

102. A method according to claim 19 wherein said wet coal is selected from a group consisting of bituminous coal, subbituminous coal, lignite, biomass, coal-biomass blends, and any combination thereof.

106. A method according to claim 19 wherein said wet coal comprises a moisture content selected from a group consisting of about 8%, about 20%, about 28%, about 38%, up to about 60%, up to about 50%, up to about 20%, up to about 25%, up to about 28%, up to about 38%, greater than about 20%, and greater than about 60%.

110. A method according to claim 19 and further comprising the step of recovering water in said system assembly.

114. A method according to claim 110 and further comprising the step treating said water.

118. A method according to claim 110 and further comprising the step of recycling said water in at least part of said power plant system assembly selected from a group consisting of a sulfur dioxide emissions scrubber, a boiler feedwater makeup, a cooling tower makeup and any combination thereof.

121. A method according to claim 65 wherein said fluidized dryer bed is configured to remove up to about 100% of the moisture of said wet coal.

20. An efficient method for generating electricity in a power plant facility comprising the steps of:

supplying wet coal in a power plant system assembly;

feeding said wet coal into at least one chamber of said power plant system assembly;

recycling a first supply of recycled non-air to said at least one chamber;

pre-process drying said wet coal with said first supply of recycled non-air in said at least one chamber for a first amount of time to create a substantially dried coal having a coal temperature of up to about 300°

F.;

recycling a second supply of recycled non-air to said substantially dried coal;

pre-process removing volatile metals from said substantially dried coal with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature up to about 600°

F.;

cooling said volatile metal reduced dried coal;

transferring said volatile metal reduced dried coal to a boiler assembly;

air fired combusting said volatile metal reduced dried coal in said boiler assembly;

producing a gaseous exhaust composed predominantly of carbon dioxide and nitrogen from said boiler assembly;

heating boiler water in said boiler assembly with heat from said combusted volatile metal reduced dried coal to create steam;

driving a turbine with said steam; and

driving at least one generator responsive to said turbine with said steam to produce electricity.

81. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said recycled non-air is selected from a group consisting of flue gas, inert gas, heated gas, carbon dioxide, nitrogen, steam, and any combination thereof.

82. An efficient method for generating electricity in a power plant facility according to claim 20 and further comprising the step of recycling said first supply of recycled non-air and said second supply of recycled non-air comes from a same source within said power plant system assembly.

83. An efficient method for generating electricity in a power plant facility according to claim 82 wherein said source comprises a recycled gaseous exhaust.

84. An efficient method for generating electricity in a power plant facility according to claim 20 and further comprising the step of recycling said first supply of recycled non-air and said second supply of recycled non-air comes from different sources within said power plant system assembly.

85. An efficient method for generating electricity in a power plant facility according to claim 84 wherein said different sources are selected from a group consisting of recycled gaseous exhaust, effluent gas from said separate volatile metal removal chamber, effluent gas from said drying chamber, a heated gas, an inert gas, carbon dioxide, nitrogen, steam, and any combination thereof.

86. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said step of recycled pre-process drying said wet coal with said first supply of recycled non-air comprises the step of providing said substantially dried coal selected from a group consisting of at least about 90% dry, at least about 91% dry, at least about 92% dry, at least about 93% dry, at least about 94% dry, at least about 95% dry, at least about 96% dry, at least about 97% dry, at least about 98% dry, at least about 99% dry, and about 100% dry.

87. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said steps of recycling said first supply of recycled non-air to said at least one chamber and said step of recycling a second supply of recycled non-air to said substantially dried coal to said separate volatile metal removal chamber comprises the step of recycling a first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber.

88. An efficient method for generating electricity in a power plant facility according to claim 87 wherein said step of recycling said first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber comprises the step of heating said first supply and second supply of recycled non-air from a single heat source.

89. An efficient method for generating electricity in a power plant facility according to claim 87 wherein said step of recycling said first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber comprises the step of heating said first supply of recycled non-air from at least two heat sources.

90. An efficient method for generating electricity in a power plant facility according to claim 87 wherein said step of recycling said first and second supply of heated recycled supply of recycled non-air to said at least one chamber and said separate volatile metal removal chamber comprises the step of heating said recycled non-air with hot gaseous exhaust located in said system selected from a group consisting of a furnace, a boiler convective pass, and a downstream flue gas location.

91. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said drying chamber is selected from a group consisting of a fluidized bed dryer, a moving bed dryer, and a fixed dryer bed.

92. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said first amount of time is selected from a group consisting of at least about 2 minutes, up to about 30 minutes, between about 5 minutes and about 30 minutes, between about 8 minutes and 16 minutes, and up to about 16 minutes.

93. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said second amount of time is selected from a group consisting of at least about 2 minutes, up to about 30 minutes, between about 5 minutes and about 30 minutes, between about 8 minutes and 16 minutes, and up to about 16 minutes.

94. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said step of pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber occurs after said step of pre-process drying said wet coal with said first supply of recycled non-air.

95. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said step of pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature up to about 600°

F. comprises the step of pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber with said second supply of recycled non-air for a second amount of time to create a volatile metal reduced dried coal having a coal temperature between about 275°

F. and about 600°

F.

96. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said step of pre-process removing volatile metals from said substantially dried coal comprises the step of providing said volatile metal reduced dried coal having a mercury removal selected from a group consisting of between about 50% and about 87%, about 80%, about 81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%, about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, and about 100%.

97. An efficient method for generating electricity in a power plant facility according to claim 20 wherein said step of pre-process removing volatile metals from said substantially dried coal in said separate volatile metal removal chamber comprises the step of removing volatile metals from said coal, said volatile metals selected from a group consisting of arsenic, selenium, cadmium, lead, and mercury.

98. An efficient method for generating electricity in a power plant facility according to claim 20 and further comprising the steps of directing a volatile metals removal effluent gas from said separate volatile metal removal chamber to said drying chamber;

and using said volatile metals removal effluent gas to dry said coal.

99. An efficient method for generating electricity in a power plant facility according to claim 98 wherein said volatile metals removal effluent gas is selected from a group consisting of nitrogen, carbon dioxide, gaseous exhaust, steam, and any combination thereof.

103. A method according to claim 20 wherein said wet coal is selected from a group consisting of bituminous coal, subbituminous coal, lignite, biomass, coal-biomass blends, and any combination thereof.

107. A method according to claim 20 wherein said wet coal comprises a moisture content selected from a group consisting of about 8%, about 20%, about 28%, about 38%, up to about 60%, up to about 50%, up to about 20%, up to about 25%, up to about 28%, up to about 38%, greater than about 20%, and greater than about 60%.

111. A method according to claim 20 and further comprising the step of recovering water in said system assembly.

115. A method according to claim 111 and further comprising the step treating said water.

119. A method according to claim 111 and further comprising the step of recycling said water in at least part of said power plant system assembly selected from a group consisting of a sulfur dioxide emissions scrubber, a boiler feedwater makeup, a cooling tower makeup and any combination thereof.

122. A method according to claim 91 wherein said fluidized dryer bed is configured to remove up to about 100% of the moisture of said wet coal.