Methods and systems for syngas production and for efficient, flexible energy generation

Patent metadata

Field	Value
Publication number	US-11142832-B2
Application number	US-201816484776-A
Country	US
Kind code	B2
Filing date	Feb 9, 2018
Priority date	Feb 9, 2017
Publication date	Oct 12, 2021
Grant date	Oct 12, 2021

Abstract

Methods for producing syngas (e.g., H2 and CO) include introducing a stream comprising H2O and CO2 to a high-temperature co-electrolysis (HTCE) unit. A CO2 sweep gas is also introduced to the HTCE unit. Both H2O and CO2 are reduced in the HTCE unit to form the syngas and to form O2 that is swept away from the HTCE unit by the CO2 sweep gas, and the O2 and CO2 are then introduced to a combustion device (e.g., a gasifier), which may be configured to generate electrical power, as a result of combusting a carbonaceous fuel in the presence of the O2 and CO2. The HTCE unit is powered at least in part by power from an electricity-generating sub-system (e.g., at least one nuclear power plant). Related systems are also disclosed.

First claim

What is claimed is:

1. A method for producing syngas comprising hydrogen (H 2 ) and carbon monoxide (CO), the method comprising:
introducing a gasifier input stream to a gasifier, the gasifier input stream comprising oxygen (O 2 ) and carbon dioxide (CO 2 );
in the gasifier, gasifying a carbonaceous fuel in the presence of the oxygen (O 2 ) and the carbon dioxide (CO 2 ) to produce a combustible gas;
combusting the gas to generate exhaust gases;
passing the exhaust gases through at least one turbine to generate power and to produce an output stream comprising carbon dioxide (CO 2 );
supplying, to a high-temperature co-electrolysis (HTCE) unit, a first input stream comprising water (H 2 O) and a portion of the carbon dioxide (CO 2 ) of the output stream;
supplying, to the HTCE unit, a second input stream comprising another portion of the carbon dioxide (CO 2 ) of the output stream;
in the HTCE unit, reducing, by co-electrolysis, both the water (H 2 O) and the portion of the carbon dioxide (CO 2 ) to produce the oxygen (O 2 ) and the syngas comprising the hydrogen (H 2 ) and the carbon monoxide (CO); and
transporting the oxygen (O 2 ) and excess carbon dioxide (CO 2 ) from the HTCE unit to the gasifier as the gasifier input stream.

2. The method of claim 1 , further comprising powering the HTCE unit using electrical power generated by at least one nuclear reactor.

3. The method of claim 2 , further comprising supplying the water (H 2 O) of the first input stream from the at least one nuclear reactor.

4. The method of claim 2 , further comprising providing at least a portion of the electrical power generated by the at least one nuclear reactor to a power grid.

5. The method of claim 2 , wherein the at least one nuclear reactor comprises a plurality of small modular reactors (SMRs).

6. The method of claim 1 , further comprising providing the power generated by the at least one turbine to a power grid.

7. The method of claim 1 , wherein all heat for operation of the HTCE unit is supplied by the water (H 2 O) and the carbon dioxide (CO 2 ) introduced to the HTCE unit.

8. The method of claim 1 , wherein all the oxygen (O 2 ) introduced to the gasifier is the oxygen (O 2 ) produced from the HTCE unit.

9. The method of claim 1 , further comprising:
powering the HTCE unit using electrical power generated by at least one nuclear reactor; and
providing, to a power grid, at least a portion of the power generated by the at least one turbine and at least a portion of the electrical power generated by the at least one nuclear reactor.

10. The method of claim 1 , further comprising powering the HTCE unit with electrical power supplied by an electricity-generating sub-system.

11. The method of claim 10 , wherein the first input stream comprising the water (H 2 O) and the portion of the carbon dioxide (CO 2 ) comprises water output from the electricity-generating sub-system.

12. The method of claim 1 , further comprising supplying the syngas to a metal reduction reactor.

13. The method of claim 1 , wherein gasifying a carbonaceous fuel comprises gasifying coal.

14. A system for producing syngas comprising hydrogen (H 2 ) and carbon monoxide (CO) and for generating electrical power, the system comprising:
a high-temperature co-electrolysis (HTCE) unit;
at least one nuclear reactor configured to provide electrical power to the HTCE unit and configured to provide steam (H 2 O) to the HTCE unit;
an integrated gasification combined cycle (IGCC) power plant;
an oxygen (O 2 ) and carbon dioxide (CO 2 ) stream line in communication with both the HTCE unit and the IGCC power plant; and
another carbon dioxide (CO 2 ) stream line in communication with both the HTCE unit and the IGCC power plant.

15. The system of claim 14 , further comprising a water separation unit operatively following the IGCC power plant and configured to separate carbon dioxide (CO 2 ) output by the IGCC from water output by the IGCC.

16. The system of claim 14 , wherein the oxygen (O 2 ) and carbon dioxide (CO 2 ) stream line exits the HTCE unit at an anode side of the HTCE unit.

17. The system of claim 14 , wherein the another carbon dioxide (CO 2 ) stream line enters the HTCE unit proximate a cathode side of the HTCE unit.

18. The system of claim 14 , wherein the IGCC power plant is not in operative communication with an air separation unit.

19. A method for producing syngas comprising hydrogen (H 2 ) and carbon monoxide (CO), the method comprising:
introducing an input stream comprising water (H 2 O) and carbon dioxide (CO 2 ) to a high-temperature co-electrolysis (HTCE) unit;
introducing a carbon dioxide (CO 2 ) sweep gas to the HTCE unit;
in the HTCE unit, reducing both the water (H 2 O) and the carbon dioxide (CO 2 ) of the input stream to form the syngas comprising the hydrogen (H 2 ) and the carbon monoxide and to form oxygen (O 2 );
sweeping the oxygen (O 2 ) away from the HTCE unit using the carbon dioxide (CO 2 ) sweep gas;
introducing the oxygen (O 2 ) and the carbon dioxide (CO 2 ) sweep gas to a combustion sub-system;
in the combustion sub-system, combusting a carbonaceous fuel in the presence of the oxygen (O 2 ) and the carbon dioxide (CO 2 ) sweep gas; and
power the HTCE unit with electrical power supplied by an electricity-generating sub-system.

20. The method of claim 19 , wherein:
the input stream comprising the water (H 2 O) and the carbon dioxide (CO 2 ) comprises carbon dioxide (CO 2 ) output from the combustion sub-system; and
the carbon dioxide (CO 2 ) sweep gas comprises additional carbon dioxide (CO 2 ) output from the combustion sub-system.

Assignees

• Battelle Energy Alliance Llc

Inventors

• O'Brien James E
• Stoots Carl M
• Mckellar Michael G
• Boardman Richard D

Classifications

• F02C3/34

  with recycling of part of the working fluid, i.e. semi-closed cycles with combustion products in the closed part of the cycle · CPC title

• C10J2300/0969

  Carbon dioxide · CPC title

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title

• C25B1/042 Primary

  by electrolysis of steam · CPC title

• C21B13/0073

  Selection or treatment of the reducing gases · CPC title