Hot rotary screw pump

• US 7,360,639 B2
• Filed: 06/16/2004
• Issued: 04/22/2008
• Est. Priority Date: 06/16/2004
• Status: Active Grant

• Current Assignee: Gas Technology Institute
• Original Assignee: Pratt & Whitney Rocketdyne Incorporated (L3Harris Technologies, Inc.)
• Inventors: Stewart, Albert E, Sprouse, Kenneth M
• Primary Examiner(s): Deuble; Mark A.
• Application Number:
  US10/869,644
• Publication Number:
  US 20060045632A1
• Time in Patent Office: 1,406 Days
• Field of Search: 198/658, 198/670, 198/671, 198/676, 406/53, 406/55, 406/61, 406/99
• US Class Current: 198/658
• CPC Class Codes: B01J 2208/00752 Feeding
• CPC Class Codes: B01J 8/002 with a moving instrument
• CPC Class Codes: C01B 2203/042 Purification by adsorption on solids
• CPC Class Codes: C01B 2203/0475 the impurity being carbon dioxide
• CPC Class Codes: C01B 3/56 by contacting with solids; Regeneration of used solids C01B3/508 takes precedence
• CPC Class Codes: Y02P 30/00 Technologies relating to oil refining and petrochemical industry

Abstract

A screw feeder can be used to transport a high temperature particulate material. A housing contains the material within the screw feeder which includes an inlet and an outlet port. A screw is rotatably positioned within the housing to advance the material from the inlet port to the outlet port, which rotates axially. A labyrinth seal can be formed around and in communication with the screw to eliminate reverse movement of the material. A cooling medium can be directed into contact with at least the housing. A fluid can be injected through the screw to prevent blockage of the particulate material. A pressure differential is created from the inlet to the outlet port of at least 0.069 MPad.

Claims

1. A screw feeder to transport a particulate material from a low pressure to a high pressure environment, the screw feeder comprising:

a housing to contain the material while it is within the screw feeder, the housing including an inlet port to receive the particulate material and an outlet port to allow the particulate material to exit the housing;

a screw rotatably mounted within the housing to advance the particulate material from the inlet port to the outlet port;

a jet port disposed in the screw, the jet port operably assisting in moving the particulate material to the outlet port; and

a cooling medium envelope operable to permit a cooling medium to contact at least the housing;

wherein a material of the screw is selected from one of a high temperature compatible metal and a ceramic material.

2. The screw feeder of claim 1, wherein the high temperature compatible material is adaptable for use at a temperature of at least 538°

C.

3. The screw feeder of claim 1, further comprising:

a stationary sleeve substantially surrounding a first end of the screw defining a low pressure end of the screw feeder;

a motor; and

a screw gear operably interconnecting the motor and the screw to rotate the screw within the stationary sleeve.

4. The screw feeder of claim 3, comprising:

a rotatable sleeve substantially surrounding a second end of the screw defining a high pressure end of the screw feeder; and

a sleeve gear operably interconnecting the motor and the rotatable sleeve;

wherein the screw gear operably drives the screw in a first rotation direction and the sleeve gear operably drives the rotatable sleeve in a second rotation direction.

5. The screw feeder of claim 4,

wherein the rotatable sleeve includes an interior and an exterior, the interior defining a groove;

wherein the screw substantially engages the groove; and

wherein the rotatable sleeve and the screw rotate in substantially opposite rotational directions.

6. The screw feeder of claim 5, wherein when the screw substantially engages the groove a seal is operably formed between the screw and the groove.

7. The screw feeder of claim 6, wherein the seal is operably formed as a tight clearance seal.

8. The screw feeder of claim 4, wherein at least the screw, the stationary sleeve and the rotatable sleeve each comprise a ceramic matrix composite material.

9. The screw feeder of claim 1, wherein the screw defines an axial bore, and the screw further defines a radial bore, wherein the radial bore operably interconnects the axial bore and the jet port, such that a fluid provided to the axial bore may be propelled out of the jet port.

10. The screw feeder of claim 1, wherein the screw includes a thread that defines a thread plane, and wherein the jet port includes a central axis operably forming an angle ranging from about 5°

to about 20°

to the thread plane.

11. The screw feeder of claim 1, wherein a volume of fluid is provided to the jet port such that the volume of fluid exits the jet port at a super-sonic velocity.

12. The screw feeder of claim 1, wherein an outlet port pressure is at least 0.069 MPa higher than an inlet port pressure.

13. A screw feeder operable to transport a particulate material from a low pressure to a high pressure environment, comprising:

a housing to contain the material while it is within the screw feeder, the housing defining an inlet port and an outlet port;

a screw rotatably disposed within the housing to advance the material from the inlet port to the outlet port, and adapted to rotate axially;

a labyrinth seal formed around and in communication with the screw to substantially eliminate reverse movement of the material; and

a cooling medium delivery device connectable to the screw feeder operable to direct a cooling medium into contact with at least a portion of the screw feeder;

wherein a pressure differential between the inlet port to the outlet port is at least 0.069 MPad.

14. The screw feeder of claim 13, further comprising:

a sleeve having an interior and an exterior substantially surrounding a length of the screw; and

a thread extending from the screw;

wherein the interior defines a groove operably cooperating with the thread to form the labyrinth seal.

15. The screw feeder of claim 14, wherein the screw is adapted to rotate axially in a first direction.

16. The screw feeder of claim 15, comprising:

a motor;

a screw gear operably interconnecting the motor and the screw to rotate the screw in the first direction; and

a sleeve gear operably interconnecting the motor and the sleeve to rotate the sleeve in a second direction;

wherein the motor drives the screw gear and the sleeve gear at substantially the same rotational speed.

17. The screw feeder of claim 13, further comprising an assistor, to operably assist the screw in advancing the material from the inlet port to the outlet port.

18. The screw feeder of claim 13,

wherein the assistor includes a jet port;

wherein the screw defines an axial bore and a radial bore; and

wherein the radial bore operably interconnects the axial bore and the jet port, such that a fluid provided to the axial bore may be propelled out of the jet port.

19. The screw feeder of claim 18, wherein the labyrinth seal substantially inhibits a flow of the fluid and the particulate material from the outlet port to the inlet port of the housing.

20. The screw feeder of claim 18, wherein the screw includes a thread defining a thread plane, and wherein the assistor includes a central axis operably formed at an angle ranging between about 2°

to about 25°

to the thread plane.

21. The screw feeder of claim 19, wherein a volume of fluid is provided to said assistor such that said volume of fluid exits the jet to operably assist transport of the particulate material.

22. The screw feeder of claim 14, wherein at least the screw and the sleeve comprise a ceramic material.

23. The screw feeder of claim 13, wherein the cooling medium delivery device comprises a jacket connectable to the housing operable to receive the cooling medium.

24. A method for transporting a high temperature particulate material using a screw pump, the screw pump including a screw, and a housing, the method comprising:

rotatably mounting the screw within the housing;

feeding the particulate material at an elevated temperature into the housing to operably contact the screw;

axially rotating the screw to operably advance the particulate material;

creating a labyrinth seal around and in communication with the screw to substantially eliminate reverse movement of the material;

directing a cooling flow to the screw pump; and

generating at least a 0.069 MPad differential pressure across the screw pump.

25. The method of claim 24, comprising constructing at least the screw and the housing of a ceramic material.

26. The method of claim 24, comprising constructing at least the screw and the housing of a high temperature compatible metal material.

27. The method of claim 24, comprising injecting a fluid through the screw into the particulate material to reduce clogging of the particulate material.

28. The method of claim 27, comprising injecting one of a carbon dioxide gas and a steam through the screw.

29. The method of claim 27, comprising creating a bore within the screw to operably receive the fluid.

30. The method of claim 24, comprising connecting the screw pump to a source of cooling medium.

31. The method of claim 24, comprising rotating the screw at a rotational speed ranging between approximately 3,600 rpm to 20,000 rpm.

32. The method of claim 24, comprising surrounding at least a portion of the screw with a non-rotating sleeve adjacent to a location where the particulate material is fed into the housing.

33. The method of claim 24, comprising sealing a rotating portion of the screw.

34. The method of claim 24, comprising rotatably supporting the screw using at least a set of bearings.