Large scale pressure swing adsorption systems having process cycles operating in normal and turndown modes

• US 8,496,733 B2
• Filed: 01/11/2011
• Issued: 07/30/2013
• Est. Priority Date: 01/11/2011
• Status: Expired due to Fees

• Current Assignee: Praxair Technology Incorporated (Linde Plc)
• Original Assignee: Praxair Technology Incorporated (Linde Plc)
• Inventors: Baksh, Mohamed S. A., Simo, Marian
• Primary Examiner(s): LAWRENCE JR, FRANK M
• Application Number:
  US13/004,719
• Publication Number:
  US 20120174777A1
• Time in Patent Office: 931 Days
• Field of Search: 95/96, 951/17, 951/27, 951/30, 951/39, 951/40, 951/43
• US Class Current: 95/96
• CPC Class Codes: B01D 2253/102 Carbon
• CPC Class Codes: B01D 2253/104 Alumina
• CPC Class Codes: B01D 2253/108 Zeolites
• CPC Class Codes: B01D 2256/16 Hydrogen
• CPC Class Codes: B01D 2259/40026 with more than three sub-steps
• CPC Class Codes: B01D 2259/40041 with more than three sub-steps
• CPC Class Codes: B01D 2259/40045 with two sub-steps
• CPC Class Codes: B01D 2259/40047 with three sub-steps
• CPC Class Codes: B01D 2259/40075 More than ten
• CPC Class Codes: B01D 2259/4068 using more than ten beds
• CPC Class Codes: B01D 2259/4145 arranged in series
• CPC Class Codes: B01D 53/047 Pressure swing adsorption

Abstract

The present invention relates to large scale pressure swing adsorption systems (i.e., ranging from twelve to sixteen beds) utilizing new and advanced cycles to obtain enhanced hydrogen recovery from a hydrogen containing feed gas (i.e., synthesis gas).

Claims

1. A pressure swing adsorption process for separating a pressurized supply feed gas containing one or more strongly adsorbable component from at least one less strongly adsorbable product gas component in a twelve bed pressure swing adsorption system to produce a continuous stream of product gas enriched in the less strongly adsorbable component and a continuous stream of offgas that is enriched in strongly adsorbable components, wherein the process cycle has four bed-to-bed equalizations steps, four of the beds are in production, and utilizes purge gas of increasing concentrations of the less strongly adsorbable product gas during the purging steps, in accordance to the following cycle chart:

2. The pressure swing adsorption process of claim 1, wherein said less strongly adsorbable product gas is hydrogen.

3. The pressure swing adsorption process of claim 1, wherein the supply feed gas containing one or more strongly adsorbable component is selected from the group consisting of hydrocarbons, carbon dioxide, carbon monoxide, argon, nitrogen, helium and water vapor.

4. The pressure swing adsorption process of claim 1, wherein each adsorbent bed contains alumina, carbon and zeolite material configured in layers disposed in this particular order for feed gas processing.

5. The pressure swing adsorption process of claim 4, where the carbon and zeolite layers are each subdivided into two layers with different particle size.

6. The pressure swing adsorption process of claim 5, where the first of the subdivided carbon layers encountered by the supply feed gas has a particle size of about 0.5 to 1.5 mm and an affinity for the carbon dioxide impurity.

7. The pressure swing adsorption process of claim 5, where the second of the subdivided carbon layers encountered by the supply feed gas has a particle size of about 2.0 to 3.0 mm and an affinity for the methane impurities.

8. The pressure swing adsorption process of claim 5, where the first of the subdivided zeolite layers encountered by the supply feed gas has a particle size of about 0.5 to 2.0 mm and an affinity for the carbon monoxide impurity.

9. The pressure swing adsorption process of claim 5, where the second of the subdivided zeolite layers encountered by the supply feed gas has a particle size of about 2.0 to 3.0 mm and an affinity for the nitrogen impurity.

10. A pressure swing adsorption process for separating a pressurized supply feed gas containing one or more strongly adsorbable component from at least one less strongly adsorbable product gas component in a eleven bed pressure swing adsorption system to produce a continuous stream of product gas enriched in the less strongly adsorbable component and a continuous stream of offgas that is enriched in strongly adsorbable components, wherein the process cycle has four bed-to-bed equalizations steps, while four of the beds are in production, and utilize purge gas of increasing concentrations of the less strongly adsorbable product gas during the purging steps.

11. The pressure swing adsorption process of claim 10, wherein the PSA cycle comprises at-least twenty two steps.

12. The pressure swing adsorption process of claim 10, in accordance to the following cycle chart:

13. A pressure swing adsorption process for separating a pressurized supply feed gas containing one or more strongly adsorbable component from at least one less strongly adsorbable product gas component in a twelve bed pressure swing adsorption system to produce a continuous stream of product gas enriched in the less strongly adsorbable component and a continuous stream of offgas that is enriched in strongly adsorbable components, wherein the process cycle has five bed-to-bed equalizations steps, three of the beds are in production, and utilize purge gas of increasing concentrations of the less strongly adsorbable product gas during the purging steps, in accordance to the following cycle chart:

14. A pressure swing adsorption process for separating a pressurized supply feed gas containing one or more strongly adsorbable component from at least one less strongly adsorbable product gas component in a fourteen bed pressure swing adsorption system to produce a continuous stream of product gas enriched in the less strongly adsorbable component and a continuous stream of offgas that is enriched in strongly adsorbable components, wherein the process cycle has five bed-to-bed equalizations steps, five of the beds are in production, and utilize purge gas of increasing concentrations of the less strongly adsorbable product gas during the purging steps.

15. The pressure swing adsorption process of claim 14, wherein the PSA cycle comprises at-least twenty eight steps.

16. The pressure swing adsorption process of claim 14, in accordance to the following cycle chart:

17. A pressure swing adsorption process for separating a pressurized supply feed gas containing one or more strongly adsorbable component from at least one less strongly adsorbable product gas component in a sixteen bed pressure swing adsorption system to produce a continuous stream of product gas enriched in the less strongly adsorbable component and a continuous stream of offgas that is enriched in strongly adsorbable components, wherein the process cycle has six bed-to-bed equalizations steps, six of the beds are in production, and utilize purge gas of increasing concentrations of the less strongly adsorbable product gas during the purging steps.

18. The pressure swing adsorption process of claim 17, wherein the PSA cycle comprises at-least thirty two steps.

19. The pressure swing adsorption process of claim 17, in accordance to the following cycle chart: