Systems and methods for gasifying a hydrocarbon feedstock

Patent metadata

Field	Value
Publication number	US-9388980-B2
Application number	US-201113326427-A
Country	US
Kind code	B2
Filing date	Dec 15, 2011
Priority date	Dec 15, 2011
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

Systems and methods for gasifying a hydrocarbon feedstock are provided. The hydrocarbon feedstock can be gasified in the presence of one or more particulates to produce a syngas and one or more carbon-containing particulates. At least a portion of the carbon of the one or more carbon-containing particulates can be combusted in a combustion process external to the gasifying of the hydrocarbon feedstock to produce a combustion gas. The combustion gas can be utilized in one or more processes external to the gasifying of the hydrocarbon feedstock.

First claim

What is claimed is:

1. A method for gasifying a hydrocarbon feedstock, comprising:
gasifying a hydrocarbon feedstock in a gasifier in the presence of one or more particulates to produce a syngas and carbon-containing particulates;
recycling the produced syngas using processes external to the gasifying of the hydrocarbon feedstock, wherein the processes external to the gasifying of the hydrocarbon feedstock sequentially comprise:
cooling the syngas by at least a first heat exchanger,
performing particulate control on the cooled syngas,
further cooling the cooled syngas after the particulate control by at least a second heat exchanger,
heating the twice cooled syngas in a combustor external to the gasifier, and
introducing the heated syngas to the gasifier;

cooling the carbon-containing particulates;
combusting at least a portion of the carbon of the cooled carbon-containing particulates in a combustion process by the combustor external to the gasifying of the hydrocarbon feedstock to produce a combustion gas; and
utilizing the combustion gas in further processes external to the gasifying of the hydrocarbon feedstock,
wherein the further processes external to the gasifying of the hydrocarbon comprise drying a moisture-containing hydrocarbon feedstock to produce a dried hydrocarbon feedstock, and
wherein the hydrocarbon feedstock comprises the dried hydrocarbon feedstock.

2. The method of claim 1 , wherein the carbon-containing particulates comprise carbon-containing coarse ash, carbon-containing fine ash, or a combination thereof.

3. The method of claim 1 , wherein the processes external to the gasifying of the hydrocarbon feedstock further comprise: heating a boiler feed water; heating at least a portion of the syngas; heating a first oxidant; heating a steam; or a combination thereof.

4. The method of claim 3 , wherein heating the boiler feed water produces a first steam, and wherein the method further comprises introducing the first steam to the gasifying of the hydrocarbon feedstock, exporting the first steam to a process external to the gasifying of the hydrocarbon feedstock, supplying the first steam to a steam turbine to produce electrical power, or a combination thereof.

5. The method of claim 3 , wherein heating the first oxidant produces a heated first oxidant, and wherein the method further comprises introducing the heated first oxidant to the gasifying of the hydrocarbon feedstock.

6. The method of claim 3 , wherein heating the steam produces a second steam, and wherein the method further comprises introducing the second steam to the gasifying of the hydrocarbon feedstock, exporting the second steam to a process external to the gasifying of the hydrocarbon feedstock, supplying the second steam to a steam turbine to produce electrical power, or a combination thereof.

7. The method of claim 1 , wherein the dried hydrocarbon feedstock has a moisture concentration ranging from about 12 wt % to about 22 wt %.

8. The method of claim 1 , wherein the particulates comprise sand, ceramic materials, ash, crushed limestone, inorganic oxides, or a combination thereof.

9. The method of claim 1 , wherein the combustor comprises one of: a slagging combustor, an ash furnace, and a pulverized-coal furnace; and the combustion process further comprising:
maintaining a molar ratio of oxygen in a sub-stoichiometric proportion during the gasifying process; and
maintaining a stoichiometric excess of combustion oxidant during the combustion process.

10. The method of claim 1 , wherein the hydrocarbon feedstock comprises one or more bituminous coals, one or more sub-bituminous coals, one or more anthracite coals, one or more petroleum cokes, or a combination thereof.

11. The method of claim 1 , wherein the gasifier is selected from one of: (i) a circulating solids gasifier, and (ii) an entrained flow gasifier.

12. The method of claim 1 , further comprising
conveying the syngas from the gasifier using a first line;
conveying at least a portion of the one or more carbon-containing particulates from the gasifier using a second line separate from the first line; and
conveying the at least a portion of the carbon-containing particulates using the second line to the hydrocarbon stock being gasified.

13. The method of claim 12 , further comprising separating the syngas from the carbon-containing particulates, wherein the separated carbon containing particulates is conveyed by the second line.

14. The method of claim 12 , wherein the coarse ash is conveyed via the second line, and the fine ash is conveyed to the hydrocarbon stock being gasified using a third line separate from the second line.

15. A method for gasifying a hydrocarbon feedstock, comprising:
gasifying a hydrocarbon feedstock in a gasifier in the presence of one or more particulates to produce a syngas and carbon-containing particulates;
recycling the produced syngas using processes external to the gasifying of the hydrocarbon feedstock, wherein the processes external to the gasifying of the hydrocarbon feedstock sequentially comprise:
cooling the syngas by at least a first heat exchanger;
performing particulate control on the cooled syngas;
further cooling the cooled syngas after the particulate control by at least a second heat exchanger;
heating the twice cooled syngas in a combustor external to the gasifier; and
introducing the heated syngas to the gasifier;

combusting at least a portion of the carbon of the carbon-containing particulates in a combustion process by the combustor external to the gasifying of the hydrocarbon feedstock to produce a combustion gas; and
utilizing the combustion gas in further processes external to the gasifying of the hydrocarbon feedstock,
wherein the further processes external to the gasifying of the hydrocarbon feedstock comprise drying a moisture-containing hydrocarbon feedstock to produce a dried hydrocarbon feedstock,
wherein the hydrocarbon feedstock comprises the dried hydrocarbon feedstock,
wherein the one or more carbon-containing particulates comprise carbon-containing coarse ash, carbon-containing fine ash, or a combination thereof, and
wherein the one or more processes external to the gasifying of the hydrocarbon feedstock comprise: heating a boiler feed water; heating a first oxidant; heating a steam; or a combination thereof.

16. The method of claim 15 , wherein heating the boiler feed water produces a first steam, heating at least a portion of the syngas produces a heated syngas, heating the first oxidant produces a heated first oxidant, heating the steam produces a second steam, and drying the moisture-containing hydrocarbon feedstock produces a dried hydrocarbon feedstock having a moisture concentration ranging from about 12 wt % to about 22 wt %, the method further comprising:
introducing the first steam to the gasifying of the hydrocarbon feedstock, exporting the first steam to a process external to the gasifying of the hydrocarbon feedstock, supplying the first steam to a steam turbine to produce electrical power, or a combination thereof;
introducing the heated syngas to the gasifying of the hydrocarbon feedstock;
introducing the heated first oxidant to the gasifying of the hydrocarbon feedstock;
introducing the second steam to the gasifying of the hydrocarbon feedstock, exporting the second steam to a process external to the gasifying of the hydrocarbon feedstock, supplying the second steam to a steam turbine to produce electrical power, or a combination thereof; and
introducing the dried hydrocarbon feedstock to the gasifying of the hydrocarbon feedstock.

Assignees

• Abughazaleh John
• Kellogg Brown & Root Llc

Inventors

• Abughazaleh John

Classifications

• F23C2900/9901

  Combustion process using hydrogen, hydrogen peroxide water or brown gas as fuel · CPC title

• C10J3/482

  Gasifiers with stationary fluidised bed · CPC title

• C10J3/84

  with means for removing dust or tar from the gas · CPC title

• C10J2300/1884

  with one stream being synthesis gas · CPC title

• C10J2300/1823

  for synthesis gas · CPC title