Systems and methods for manufacture of methanol from natural gas and flare gas feedstock

• US 9,637,433 B2
• Filed: 02/13/2016
• Issued: 05/02/2017
• Est. Priority Date: 11/28/2014
• Status: Active Grant

• Current Assignee: Pioneer Energy, Inc.
• Original Assignee: Pioneer Energy, Inc.
• Inventors: Zubrin, Robert M, Nizamov, Boris, Siebarth, James, Berggren, Mark, Henshaw, Thomas L, Kortan, Adam M, Apke, Colin
• Primary Examiner(s): YOUNG, NATASHA E
• Application Number:
  US15/043,558
• Publication Number:
  US 20160159714A1
• Time in Patent Office: 444 Days
• CPC Class Codes: B01J 19/245 placed in series
• CPC Class Codes: B01J 2208/025 Two or more types of catalyst
• CPC Class Codes: B01J 2219/24 Stationary reactors without moving elements inside
• CPC Class Codes: B01J 8/02 with stationary particles, e.g. in fixed beds
• CPC Class Codes: B01J 8/0278 Feeding reactive fluids for solid material B01J8/0015
• CPC Class Codes: B01J 8/0492 Feeding reactive fluids for solid material, see B01J8/0015
• CPC Class Codes: B01J 8/0496 Heating or cooling the reactor
• CPC Class Codes: C01B 2203/0233 the reforming step being a steam reforming step
• CPC Class Codes: C01B 2203/0244 the reforming step being an autothermal reforming step, e.g. secondary reforming processes
• CPC Class Codes: C01B 2203/061 Methanol production
• CPC Class Codes: C01B 2203/0805 Methods of heating the process for making hydrogen or synthesis gas
• CPC Class Codes: C01B 2203/0883 by indirect heat exchange
• CPC Class Codes: C01B 2203/1076 Copper or zinc-based catalysts
• CPC Class Codes: C01B 2203/1241 Natural gas or methane
• CPC Class Codes: C01B 2203/1258 Pre-treatment of the feed
• CPC Class Codes: C01B 2203/84 Energy production
• CPC Class Codes: C01B 3/38 using catalysts
• CPC Class Codes: C01B 3/382 Multi-step processes
• CPC Class Codes: C07C 29/1518 one step being the formation of initial mixture of carbon oxides and hydrogen for synthesis
• CPC Class Codes: C07C 29/152 characterised by the reactor used
• CPC Class Codes: C07C 31/04 : Methanol
• CPC Class Codes: F02B 5/02 : Methods of operating
• CPC Class Codes: F02B 63/04 : for electric generators
• CPC Class Codes: F02M 21/0206 : Non-hydrocarbon fuels, e.g. hydrogen, ammonia or carbon monoxide
• CPC Class Codes: Y02P 20/129 : Energy recovery, e.g. by cogeneration, H2recovery or pressure recovery turbines
• CPC Class Codes: Y02T 10/30 : Use of alternative fuels, e.g. biofuels

Abstract

A mobile system and method that reform flare gas, methane, or natural gas, using air without steam, to directly produce methanol, a clean burning gasoline blend, component, and/or substitute are disclosed. The system first reforms the air-methane mixture at ambient atmospheric pressure, then compresses the resulting CO-hydrogen-nitrogen gas mixture to 600 psi, and feeds it through a methanol reactor which reacts the gas mixture directly into methanol. The nitrogen is returned by the system back to the atmosphere. Methanol is a clean burning gasoline substitute, and can be used to displace significantly costlier and dirtier petroleum-based fuel, while solving a critical problem with flaring. For example, the over 120 billion cubic feet per year that was flared in North Dakota in 2014 could be converted into over 6 million tons of methanol.

Claims

1. A mobile system for converting raw natural gas into methanol, comprising:

a syngas generator for generating syngas from the raw natural gas and air;

a syngas compressor for compressing the syngas;

a reactor for converting carbon monoxide and hydrogen in the syngas to methanol, wherein energy is exchanged between streams entering and exiting a catalyst bed of the reactor to reduce duties on preheating and cooling of the syngas; and

a power generator for using unreacted carbon monoxide and hydrogen to generate power, wherein some of the power is used to power the syngas compressor.

2. The system of claim 1, further comprising:

a sulfur removal unit for removing sulfur from the raw natural gas.

3. The system of claim 1, wherein the syngas generator comprises an air reforming unit for reforming the raw natural gas and air in presence of a steam reforming catalyst.

4. The system of claim 3, wherein air enriched in oxygen is added to the air reforming unit to increase concentrations of the carbon monoxide and the hydrogen in the syngas.

5. The system of claim 3, wherein distilled water is added to the air reforming unit for preventing catalyst coking.

6. The system of claim 5, wherein the distilled water is recycled to the air reforming unit from a condenser downstream from an air recycling unit.

7. The system of claim 5, wherein the distilled water is converted to steam inside the air reforming unit.

8. The system of claim 1, wherein a gas mixer mixes the raw natural gas and the air before these gases pass through a syngas catalyst bed in the syngas generator.

9. The system of claim 1, wherein the raw natural gas and air are preheated to improve carbon monoxide yield.

10. The system of claim 1, wherein the catalyst bed in the reactor comprises a syngas-to-methanol synthesis catalyst.

11. The system of claim 10, wherein the syngas-to-methanol synthesis catalyst is Cu—

ZnO.

12. The system of claim 1, wherein the methanol is removed from an effluent of the catalyst bed of the reactor.

13. The system of claim 12, further comprising a heat exchanger to cool effluent gases to temperature at which most of methanol vapor condenses to liquid, a phase separator to separate liquid methanol from gases, and a component for draining liquid methanol.

14. The system of claim 1, wherein the syngas is preheated before the catalyst bed of the reactor.

15. The system of claim 1, wherein the carbon monoxide conversion to methanol is enhanced by using a recycle blower.

16. The system of claim 1, wherein the carbon monoxide conversion to methanol is enhanced by using cascading catalyst beds with methanol being removed between the cascading catalyst beds.

17. The system of claim 1, wherein the unreacted carbon monoxide and hydrogen are used to generate mechanical or electrical power.

18. The system of claim 17, wherein the electrical power is generated by combusting the unreacted carbon monoxide and hydrogen in a spark ignited internal combustion engine, and using engine power to drive an electric generator.

19. A mobile system for converting raw natural gas into methanol, comprising:

a syngas generator for generating syngas from the raw natural gas and air;

a syngas compressor for compressing the syngas;

a reactor for converting carbon monoxide and hydrogen in the syngas to methanol in a methanol synthesis reaction, wherein energy released in the methanol synthesis reaction is removed from a catalyst bed of the reactor; and

a power generator for using unreacted carbon monoxide and hydrogen from the reactor to generate power, wherein some of the power is used to power the syngas compressor.

20. The system of claim 19, wherein the syngas generator comprises an air reforming unit for reforming the raw natural gas and the air in a presence of a steam reforming catalyst.

21. The system of claim 20, wherein air enriched in oxygen is added to the air reforming unit to increase concentrations of the carbon monoxide and the hydrogen in the syngas.

22. The system of claim 20, wherein water is added to the air reforming unit for preventing catalyst coking.

23. The system of claim 22, wherein the water is recycled to the air reforming unit from a condenser downstream from an air recycling unit.

24. The system of claim 19, wherein the catalyst bed in the reactor comprises a syngas-to-methanol synthesis catalyst, and wherein the syngas-to-methanol synthesis catalyst is Cu—

ZnO.

25. The system of claim 19, wherein the methanol is removed from an effluent of the catalyst bed of the reactor, and the system further comprises a heat exchanger to cool effluent gases to temperature at which most of methanol vapor condenses to liquid, a phase separator to separate liquid methanol from gases, and a component for draining liquid methanol.

26. The system of claim 19, wherein the carbon monoxide conversion to methanol is enhanced by using a recycle blower.

27. The system of claim 19, wherein the carbon monoxide conversion to methanol is enhanced by using cascading catalyst beds with methanol being removed between the cascading catalyst beds.

28. A mobile system for converting raw natural gas into methanol, comprising:

a syngas generator for generating syngas from the raw natural gas and air;

a syngas compressor for compressing the syngas;

a reactor for converting carbon monoxide and hydrogen in the syngas to methanol, wherein some of the syngas is recirculated back to the syngas generator to prevent hot spots in a catalyst bed of the reactor; and

a power generator for using unreacted carbon monoxide and hydrogen to generate power, wherein some of the power is used to power the syngas compressor.

29. The system of claim 28, wherein the syngas generator comprises an air reforming unit for reforming the raw natural gas and the air in a presence of a steam reforming catalyst.

30. The system of claim 29, wherein air enriched in oxygen is added to the air reforming unit to increase concentrations of hydrogen and carbon monoxide in the syngas.

31. The system of claim 29, wherein water is added to the air reforming unit for preventing catalyst coking.

32. The system of claim 31, wherein the water is recycled to the air reforming unit from a condenser downstream from an air recycling unit.

33. The system of claim 28, wherein the catalyst bed in the reactor comprises a syngas-to-methanol synthesis catalyst, and wherein the syngas-to-methanol synthesis catalyst is Cu—

ZnO.

34. The system of claim 28, wherein the methanol is removed from an effluent of the catalyst bed of the reactor, and the system further comprises a heat exchanger to cool effluent gases to temperature at which most of methanol vapor condenses to liquid, a phase separator to separate liquid methanol from gases, and a component for draining liquid methanol.

35. The system of claim 28, wherein the carbon monoxide conversion to methanol is enhanced by using a recycle blower.

36. The system of claim 28, wherein the carbon monoxide conversion to methanol is enhanced by using cascading catalyst beds with methanol being removed between the cascading catalyst beds.