Method and system for upgrading biogas

Patent metadata

Field	Value
Publication number	US-10760024-B2
Application number	US-201916556944-A
Country	US
Kind code	B2
Filing date	Aug 30, 2019
Priority date	Jul 10, 2018
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

A method for providing renewable natural gas (RNG) includes removing hydrogen sulfide and/or carbon dioxide from biogas to provide partially purified biogas, which may be stored in a mobile storage tank. The partially purified biogas is transported to a biogas upgrading facility, at least partially by truck, rail, or ship. At the biogas upgrading facility, the partially purified biogas is further purified to provide the RNG, which can be injected into a distribution system (e.g., natural gas grid) and/or provided for use in transportation.

First claim

The invention claimed is:

1. A method for upgrading biogas comprising:
(a) obtaining biogas from a plurality of biogas sources, including a first biogas from a first biogas source and a second other biogas from a second other biogas source;
(b) removing one or more components from the first biogas to produce a first partially purified biogas having a non-methane content of at least 10%, said one or more components comprising hydrogen sulfide, carbon dioxide, or a combination thereof, said one or more components removed using at least one stationary purification system;
(c) transporting a first vessel containing the first partially purified biogas from the first biogas source directly to a biogas upgrading facility;
(d) removing one or more components from the second biogas to produce a second partially purified biogas, said one or more components comprising hydrogen sulfide, carbon dioxide, or a combination thereof, said one or more components removed using at least one stationary purification system;
(e) transporting a second vessel containing the second partially purified biogas from the second biogas source directly to the biogas upgrading facility;
(f) at the biogas upgrading facility, removing at least one component from a gas stream comprising the first partially purified biogas, the second partially purified biogas, or a combination thereof, to produce renewable natural gas having a heating value that is greater than a heating value of any one of the first and second partially purified biogases;
(g) providing the renewable natural gas produced in f) for injection into a distribution system, for use as a transportation fuel, or for a combination thereof.

2. The method according to claim 1 , wherein the one or more components removed in step (b) comprise carbon dioxide.

3. The method according to claim 2 , wherein the at least one component removed in step (f) comprises carbon dioxide.

4. The method according to claim 3 , wherein the first partially purified biogas has a heating value of at least 750 BTU/scf and less than 925 BTU/scf.

5. The method according to claim 2 , wherein step (b) comprises removing at least 50% of the carbon dioxide in the first biogas.

6. The method according to claim 2 , wherein step (b) comprises removing at least 75% of the carbon dioxide in the first biogas.

7. The method according to claim 2 , wherein step (b) comprises removing at least 85% of the carbon dioxide in the first biogas.

8. The method according to claim 2 , wherein the first partially purified biogas has a carbon dioxide content that is less than 8%.

9. The method according to claim 1 , wherein the first partially purified biogas has a nitrogen content that is at least 5%, and where step f) comprises removing nitrogen.

10. The method according to claim 1 , wherein the one or more components removed in steps (b) and (d) comprise carbon dioxide, water, and hydrogen sulfide.

11. The method according to claim 4 , wherein the one or more components removed in steps (b) and (d) comprise carbon dioxide, water, and hydrogen sulfide.

12. The method according to claim 1 , wherein the plurality of biogas sources comprises a third biogas source, wherein the biogas upgrading facility is connected to the third biogas source by a piping system, and wherein the third biogas source is a landfill.

13. The method according to claim 1 , wherein the first vessel is transported to the biogas upgrading facility by vehicle, wherein the vehicle is a truck, rail car, or ship.

14. The method according to claim 1 , wherein the first vessel is transported to the biogas upgrading facility in a trailer, by truck.

15. The method according to claim 1 , wherein the first vessel is filled with the first partially purified biogas to a pressure of at least 1000 psig.

16. The method according to claim 1 , wherein step b) comprises subjecting the first biogas from the first biogas source to a membrane separation.

17. The method according to claim 1 , wherein the first and second vessels are powered by natural gas, renewable natural gas, or a combination thereof.

18. The method according to claim 1 , wherein the plurality of biogas sources are selected to provide the biogas upgrading facility with biogas at rate of at least 2,000 SCFM.

19. The method according to claim 1 , wherein the plurality of biogas sources are selected to provide the biogas upgrading facility with biogas at rate of at least 5,000 SCFM.

20. A method for upgrading biogas comprising:
(a) obtaining biogas from a plurality of biogas sources, including a first biogas from a first biogas source and a second other biogas from a second other biogas source;
(b) feeding the first biogas into a first stationary purification system to remove hydrogen sulfide, carbon dioxide, or a combination thereof from the first biogas and produce a first partially purified biogas having a heating value that does not exceed 900 BTU/scf;
(c) transporting a first vessel containing the first partially purified biogas from the first biogas source directly to a biogas upgrading facility by vehicle;
(d) feeding the second biogas into a second other stationary purification system to remove hydrogen sulfide, carbon dioxide, or a combination thereof from the second biogas and produce a second partially purified biogas having a heating value that does not exceed 900 BTU/scf;
(e) transporting a second vessel containing the second partially purified biogas from the second biogas source directly to the biogas upgrading facility by vehicle;
(f) at the biogas upgrading facility, feeding the first and second partially purified biogases into one or more purification systems to remove carbon dioxide, nitrogen, oxygen, or any combination thereof and to produce renewable natural gas having a heating value that is at least 950 BTU/scf;
(g) providing renewable natural gas produced in f) for injection into a distribution system, for use as a transportation fuel, or for a combination thereof.

21. The method according to claim 1 , wherein at least one of the first and second biogas sources produces raw biogas at a rate between 100 SCFM and 3000 SCFM.

22. The method according to claim 1 , wherein at least one of the first and second biogas sources produces raw biogas at a rate between 3000 SCFM and 6000 SCFM.

Assignees

• Iogen Corp

Inventors

• Foody Patrick J
• Dechman John

Classifications

• B01D53/1468

  Removing hydrogen sulfide · CPC title

• B01D2258/05

  Biogas · CPC title

• B01D53/047

  Pressure swing adsorption · CPC title

• B01D2257/708

  Volatile organic compounds V.O.C.'s · CPC title

• B01D2257/80

  Water · CPC title