Circulating fluidized bed with moving bed downcomers and gas sealing between reactors

• US 10,010,847 B2
• Filed: 11/08/2011
• Issued: 07/03/2018
• Est. Priority Date: 11/08/2010
• Status: Active Grant

• Current Assignee: Ohio State Innovation Foundation (Ohio State University)
• Original Assignee: Ohio State Innovation Foundation (Ohio State University)
• Inventors: Fan, Liang-Shih, Li, Fanxing, Wang, Fei, Tong, Andrew S., Karri, Surya B. R., Findlay, John G., Knowlton, Ted M., Cocco, Raymond A.
• Primary Examiner(s): Nguyen, Huy-Tram
• Application Number:
  US13/883,795
• Publication Number:
  US 20140034134A1
• Time in Patent Office: 2,429 Days
• Field of Search: 422129, 422139, 422187, 422211, 422600, 422620, 422630, 422631, 501 1, 502100, 502300
• CPC Class Codes: B01J 2208/00389 using electric heating or cooling elements
• CPC Class Codes: B01J 2208/00495 using insulating materials or refractories
• CPC Class Codes: B01J 2208/00504 by means of a burner
• CPC Class Codes: B01J 2208/00539 Pressure
• CPC Class Codes: B01J 2208/00548 Flow
• CPC Class Codes: B01J 2208/0061 Controlling the level
• CPC Class Codes: B01J 2208/0084 inside the bed, e.g. baffles
• CPC Class Codes: B01J 8/0055 using cyclones
• CPC Class Codes: B01J 8/006 by filtration
• CPC Class Codes: B01J 8/087 Heating or cooling the reactor
• CPC Class Codes: B01J 8/125 with multiple sections one above the other separated by distribution aids, e.g. reaction and regeneration sections
• CPC Class Codes: B01J 8/1836 Heating and cooling the reactor B01J8/42 takes precedence
• CPC Class Codes: B01J 8/1872 Details of the fluidised bed reactor B01J8/1836 takes precedence
• CPC Class Codes: B01J 8/26 with two or more fluidised beds, e.g. reactor and regeneration installations
• CPC Class Codes: B01J 8/28 the one above the other
• CPC Class Codes: B01J 8/388 externally, i.e. the particles leaving the vessel and subsequently re-entering it
• CPC Class Codes: C01B 3/063 Cyclic methods
• CPC Class Codes: C01B 3/105 Cyclic methods
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y10T 137/0318 Processes

Abstract

A system and process for carrying out one or more chemical reactions are provided and include one or more chemical reactors having particulate solids forming a bed therein, and a gas stripping zone forming a non-mechanical seal between said reactors which includes a conduit connecting the reactors. The conduit includes an inlet for a stripping gas which is adapted to prevent process gas from passing between reactors while permitting particulate solids to pass between reactors.

Claims

1. A system for carrying out one or more chemical reactions comprising:

a first chemical reactor having an inlet and an outlet for particulate solids, said particulate solids forming a bed in said first reactor, said outlet including a transition zone which narrows the internal diameter of said first reactor, said first reactor including an inlet for a solid or gaseous reactant and an outlet for a process gas;

a second chemical reactor having an inlet and an outlet for particulate solids, said particulate solids forming a bed in said second reactor, said second reactor including an inlet for a solid or gaseous reactant and an outlet for a process gas;

a first gas stripping zone forming a non-mechanical seal between said first and second reactors comprising a conduit connecting said first reactor with said second reactor, said conduit including a first end communicating with the solids outlet of said first chemical reactor and a second end communicating with the solids inlet of said second reactor, said first end of said conduit including an inlet for a stripping gas located between said first and second ends, said first gas stripping zone adapted to prevent process gas from said first reactor from entering said second reactor while permitting said particulate solids to pass from said first reactor into said second reactor;

a third chemical reactor communicating with said second chemical reactor, said third reactor having an inlet and an outlet for particulate solids, said particulate solids forming a bed in said third reactor;

a riser section communicating with the particulate solids outlet of said third reactor, said riser section adapted to recirculate entrained solids to said first reactor, said third reactor further including a source of gas; and

a second gas stripping zone forming a non-mechanical seal between said second and third reactors comprising a conduit connecting said second reactor with said third reactor, said conduit including a first end communicating with the solids outlet of said second chemical reactor and a second end communicating with the solids inlet of said third reactor, said first end of said conduit including an inlet for a stripping gas located between said first and second ends said second gas stripping zone adapted to prevent process gas from said second reactor from entering said third reactor while permitting said particulate solids to pass from said second reactor into said third reactor.

2. A system as claimed in claim 1 in which said first gas stripping zone comprises a zone steal standpipe.

3. A system as claimed in claim 2 in which said zone seal standpipe includes a tapered section between said solids outlet of said first chemical reactor and said solids inlet of said second chemical reactor.

4. A system as claimed in claim 1 including a solids recovery device communicating with said riser section, said solids recovery device comprising a particulate separator for removing fine particulates from said system.

5. A system as claimed in claim 4 including a solids inventory device adapted to contain particulate solid particles, said solids inventory device communicating with said solids recovery device for receiving recovered particulate solids and communicating with said first chemical reactor for supplying particulate solids to said first reactor.

6. A system as claimed in claim 5 including a third gas stripping zone between said solids inventory device and said first reactor.

7. A system as claimed in claim 1 in which said first gas stripping zone comprises a standpipe forming a transitional gas discharge device, said standpipe having an end communicating with said first reactor, said end including a gas outlet communicating with said outlet for process gas in said first reactor for discharging gas from said standpipe.

8. A system as claimed in claim 7 in which said gas outlet in said gas outlet in said standpipe is selected from a plurality of porous filters, straight slits, angled silts, and holes.

9. A system as claimed in claim 7 including a fines discharge device positioned on the circumference of an inner wall of said first reactor.

10. A system as claimed in claim 3 including a solids circulation control device positioned between said second and third reactors and adapted to control the circulation rate of said particulate solids and to prevent gas mixing between said second and third reactors.

11. A system as claimed in claim 10 in which said solids circulation control device comprises a non-mechanical seal device selected from a standpipe, a loop seal, a V-valve, an L-valve, a J-valve, and an H-valve.

12. A system as claimed in claim 1 including a solid particulate bed height monitoring device positioned in said first reactor comprising a capacitance sensor.

13. A process for circulating gaseous and solid materials through a series of three chemical reactors comprising:

controlling the flow of solids and gases through each reactor such that process gases from one reactor are prevented from entering a different reactor while permitting solids to pass from one rector to another by positioning a stripping gas zone having first and second ends between said reactors and injecting a stripping gas into said zone between said first and second ends such that the gas pressure where stripping gas is injected is greater than or equal to the pressure at either end of said zone said stripping gas zone having a reduced cross sectional area as compared with said reactors to control solids flow between reactors; and

recirculating entrained solids to one reactor through a riser communicating with a solids outlet of another reactor.