Shale shaker

• US 9,079,222 B2
• Filed: 04/30/2010
• Issued: 07/14/2015
• Est. Priority Date: 10/10/2008
• Status: Active Grant

• Current Assignee: National Oilwell Varco LP (NOV, Inc.)
• Original Assignee: National Oilwell Varco LP (NOV, Inc.)
• Inventors: Burnett, George Alexander, Larson, Thomas Robert
• Primary Examiner(s): Rodriguez, Joseph C
• Assistant Examiner(s): KUMAR, KALYANAVENKA K
• Application Number:
  US12/771,201
• Publication Number:
  US 20100270216A1
• Time in Patent Office: 1,901 Days
• Field of Search: 209/258, 209/311, 209/314, 209/315, 209/360
• US Class Current: 1/1
• CPC Class Codes: B01D 33/0376 supported
• CPC Class Codes: B01D 33/41 in series connection
• CPC Class Codes: B07B 1/46 Constructional details of screens in general; Cleaning or heating of screens
• CPC Class Codes: B07B 13/16 Feed or discharge arrangements
• CPC Class Codes: B07B 2201/04 Multiple deck screening devices comprising one or more superimposed screens
• CPC Class Codes: B07B 2230/01 Wet separation

Abstract

A shale shaker for separating solids from solids laden drilling fluid is disclosed as having a basket with a scalping screen deck, at least one first screen deck and at least one second screen deck. The basket further may have a flow tray arranged between said scalping screen deck and at least one first screen deck, and a plurality of first ducts and a plurality of second ducts, the plurality of first ducts for directing solids laden drilling fluid to the at least one first screen deck. The second plurality of second ducts are for directing solids laden drilling fluid to said second screen deck.

Claims

1. A shale shaker for separating solids from solids laden drilling fluid, the shale shaker comprising:

a basket;

a first screen deck mounted in said basket;

a second screen deck mounted in said basket and positioned below said first screen deck;

a flow manifold comprising a plurality of first flow ducts and a plurality of second flow ducts interleaved with said first flow ducts, wherein said flow manifold is adapted to receive an unchanneled flow of solids laden drilling fluid, said plurality of first flow ducts being adapted to receive a first portion of said unchanneled flow and channel said first portion to said first screen deck, and said plurality of second flow ducts being adapted to receive a second portion of said unchanneled flow and channel said second portion to said second screen deck; and

a non-channeled flow tray mounted in said basket and positioned above said first screen deck, wherein said non-channeled flow tray is adapted to feed said unchanneled flow to said flow manifold.

2. A shale shaker as claimed in claim 1, wherein each of said plurality of first flow ducts comprises a respective first duct opening and each of said plurality of second flow ducts comprises a respective second duct opening.

3. A shale shaker as claimed in claim 2, wherein said plurality of first duct openings are interleaved with said plurality of second duct openings, said plurality of first and second duct openings being arranged substantially perpendicularly to a flow direction of said unchanneled flow of solids laden drilling fluid.

4. A shale shaker as claimed in claim 2, wherein said non-channeled flow tray has a floor and at least one of said pluralities of first and second duct openings is substantially planar with said floor of said non-channeled flow tray.

5. A shale shaker as claimed in claim 1, wherein said non-channeled flow tray has a feed end and a discharge end, the pluralities of first and second flow ducts being arranged at said discharge end of said non-channeled flow tray.

6. A shale shaker as claimed in claim 1, wherein said non-channeled flow tray further comprises a valve for directing said unchanneled flow of solids laden drilling fluid to one of said first screen deck and said pluralities of first and second flow ducts.

7. A shale shaker as claimed in claim 6, wherein said non-channeled flow tray has at least one gate opening therein and said valve is a gate valve comprising a slidably movable gate tray that is adapted to be slidably moved between a closed position closing off said gate opening to an open position opening said gate opening.

8. A shale shaker as claimed in claim 7, wherein a level of at least one of said pluralities of first and second duct openings is positioned below a level of said slidably movable gate tray.

9. A shale shaker as claimed in claim 1, further comprising a scalping screen that is positioned above said non-channeled flow tray, said scalping screen being adapted to remove a portion of said solids from said solids laden drilling fluid, to direct said unchanneled flow of solids laden drilling fluid to said non-channeled flow tray and to direct said removed portion of said solids to a discharge end of said shale shaker.

10. A shale shaker as claimed in claim 9, wherein said scalping screen is further adapted to direct said removed portion of said solids into one of a:

skip;

and ditch.

11. A shale shaker as claimed in claim 1, wherein said first screen deck has a screened fluid flow tray positioned thereunder, said screened fluid flow tray being adapted for collecting and guiding drilling fluid that is screened by said first screen deck.

12. A shale shaker as claimed in claim 11, wherein said basket further comprises at least one discharge duct for directing said screened drilling fluid from said screened fluid flow tray to a sump arranged beneath said basket.

13. A shale shaker as claimed in claim 1, wherein said second screen deck has a screened fluid flow tray positioned thereunder, said screened fluid flow tray being adapted for collecting and guiding drilling fluid that is screened by said second screen deck.

14. A shale shaker as claimed in claim 1, wherein said basket further comprises a trough that is arranged under a solids discharge end of said first screen deck, said trough being adapted to receive solids discharged from said solids discharge end.

15. A shale shaker as claimed in claim 14, further comprising a sump arranged below said basket, wherein said trough is adapted to feed solids into said sump.

16. A shale shaker as claimed in claim 15, wherein the basket further comprises a flexible duct that is adapted to direct a flow of solids from said trough to said sump.

17. A shale shaker as claimed in claim 14, said basket further comprising a jetting nozzle that is adapted to jet screened drilling fluid into said trough to facilitate a flow of solids therethrough.

18. A shale shaker as claimed in claim 1, wherein said basket further comprises a trough and a diverter plate, wherein said trough is arranged under a solids discharge end of said first screen deck and said diverter plate is adapted to guide solids discharged from said solids discharge end into said trough.

19. A shale shaker as claimed in claim 1, wherein said basket further comprises a trough and a diverter plate, wherein said trough is arranged under a solids discharge end of said first screen deck and said diverter plate is adapted to inhibit solids discharged from said solids discharge end from flowing into said trough.

20. A shale shaker as claimed in claim 19, further comprising one of a skip and a ditch, wherein said diverter plate is adapted to guide solids into said one of said skip and said ditch.

21. A shale shaker as claimed in claim 1, wherein said first screen deck comprises a left-hand first screen deck and a right-hand first screen deck.

22. A shale shaker as claimed in claim 21, wherein said second screen deck comprises a left-hand second screen deck and a right-hand second screen deck.

23. The shale shaker of claim 22, wherein at least two of said plurality of first flow ducts are adapted to feed said left-hand first screen deck, at least two of said plurality of first flow ducts are adapted to feed said right-hand first screen deck, at least two of said plurality of second flow ducts are adapted to feed said left-hand second screen deck, and at least two of said plurality of second flow ducts are adapted to feed said right-hand second screen deck.

24. A shale shaker as claimed in claim 1, wherein said basket has a feed end and a solids discharge end, said first screen deck being arranged at an uphill angle relative to horizontal from said feed end of said basket to said solids discharge end.

25. A shale shaker as claimed in claim 1, further comprising a first screen assembly in said first screen deck and a second screen assembly in said second screen deck.

26. A shale shaker as claimed in claim 25, wherein said first screen assembly has first screening material thereon and said second screen assembly has second screening material thereon, wherein the mesh size of the first screening material is substantially the same as the mesh size of the second screening material.

27. A shale shaker as claimed in claim 25, wherein said first screen assembly has first screening material thereon and said second screen assembly has second screening material thereon, wherein the mesh size of the second screening material is finer than the mesh size of the first screening material.

28. A shale shaker as claimed in claim 1, further comprising a fixed base, said basket suspended from the base on at least one spring, said basket further comprising a vibrating apparatus for vibrating said basket and the first and second screen decks mounted therein.

29. A method for separating solids from solids laden drilling fluid, the method comprising:

directing an unchanneled flow of solids laden drilling fluid in a flow direction along a non-channeled flow tray, wherein said non-channeled flow tray is mounted in a basket of a shale shaker;

feeding said unchanneled flow of solids laden drilling fluid to a flow manifold of said shale shaker, said flow manifold comprising a plurality of first flow ducts and a plurality of second flow ducts interleaved with said first flow ducts;

receiving a first portion of said unchanneled flow with said plurality of first flow ducts, and channeling said first portion with said plurality of first flow ducts to a first screen deck mounted in said basket below said non-channeled flow tray; and

receiving a second portion of said unchanneled flow with said plurality of second flow ducts, and channeling said second portion with said plurality of second flow ducts to a second screen deck mounted in said basket below said first screen deck.

30. A shale shaker for separating solids from solids laden drilling fluid, the shale shaker comprising:

a basket;

a scalping screen mounted in said basket;

a non-channeled flow tray mounted in said basket and positioned below said scalping screen;

a first screen deck mounted in said basket and positioned below said non-channeled flow tray;

a second screen deck mounted in said basket and positioned below said first screen deck; and

a flow manifold comprising a plurality of first flow ducts and a plurality of second flow ducts interleaved with said first flow ducts, wherein said flow manifold is adapted to receive an unchanneled flow of solids laden drilling fluid from said non-channeled flow tray, said plurality of first flow ducts being adapted to receive a first portion of said unchanneled flow and channel said first portion to said first screen deck, and said plurality of second flow ducts being adapted to receive a second portion of said unchanneled flow and channel said second portion to said second screen deck.

31. A shale shaker as claimed in claim 30, wherein said non-channeled flow tray has at least one gate opening therein and a gate valve comprising a slidably movable gate tray that is adapted to be slidably moved between a closed position closing off said gate opening to an open position opening said gate opening and allowing solids laden drilling fluid to flow therethrough.

32. A shale shaker as claimed in claim 31, wherein said basket further comprises a screened fluid flow tray mounted therein and positioned below said first screen deck, said screened fluid flow tray having a selector opening therein and a selector gate valve that is adapted for selectively opening and closing said selector opening to selectively allow screened drilling fluid to flow therethrough and onto said second screen deck.

33. A method for separating solids laden drilling fluid with a shale shaker, the method comprising:

feeding a flow of solids laden drilling fluid to a scalping deck that is mounted in a basket of said shale shaker;

separating at least a first portion of solids material from said flow of solids laden drilling fluid by passing said at least said first portion of solids material over a scalping screen of said scalping deck to a discharge end of said scalping deck;

passing a flow of a first unseparated portion of said solids laden drilling fluid through said scalping screen to a first screen deck that is mounted in said basket and positioned below said scalping deck;

separating at least a second portion of solids material from said flow of said first unseparated portion of said solids laden drilling fluid by passing said at least said second portion of solids material over a first screen assembly of said first screen deck to a discharge end of said first screen deck; and

guiding a flow of said at least said second portion of solids material into a trough that is mounted in said basket and positioned adjacent to said discharge end of said first screen deck, wherein guiding said flow comprises guiding said flow with a diverter plate that is operatively coupled to said trough.

34. A method in accordance with claim 33, further comprising flowing said at least said second portion of solids from said trough into a sump positioned under said basket.

35. A method in accordance with claim 34, wherein flowing said at least said second portion of solids through the trough is facilitated by a jet of drilling fluid.

36. A method in accordance with claim 34, further comprising passing a flow of a second unseparated portion of said solids laden drilling fluid through said first screen assembly to a second screen deck that is mounted in said basket and positioned below said first screen deck, and separating at least a further portion of solids material from said flow of said second unseparated portion of said solids laden drilling fluid by passing said at least said further portion of solids material over a second screen assembly of said second screen deck to a discharge end of said second screen deck.

37. A method in accordance with claim 36, further comprising passing a flow of a further unseparated portion of said solids laden drilling fluid through said second screen assembly to said sump.

38. A shale shaker for separating solids from solids laden drilling fluid, the shale shaker comprising:

a basket;

a first screen deck mounted in said basket, wherein said first screen deck is adapted to receive a flow of said solids laden drilling fluid and separate said flow of said solids laden drilling fluid into a flow of a first solids portion and a flow of a first solids laden drilling fluid portion;

a second screen deck mounted in said basket below said first screen deck, wherein said second screen deck is adapted to receive at least part of said flow of said first solids laden drilling fluid portion and separate said at least said part of said flow of said first solids laden drilling fluid portion into a flow of a second solids portion and a flow of a second solids laden drilling fluid portion;

a sump positioned below said basket, wherein said sump is adapted to receive said flow of said first solids portion and said flow of said second solids laden drilling fluid portion;

a trough arranged in said basket at a solids discharge end of said first screen deck, wherein said trough is adapted to receive said flow of said first solids portion discharged from said first screen deck and direct said flow of said first solids portion to said sump for mixing with said flow of said second solids laden drilling fluid portion; and

a diverter plate that is adapted to selectively allow said flow of said first solids portion discharged from said first screen deck to flow into said trough.

39. A shale shaker as claimed in claim 38, further comprising a flexible duct leading from said trough to said sump.

40. A shale shaker as claimed in claim 38, further comprising a scalping deck mounted in said basket, wherein said first screen deck is adapted to receive said flow of said solids laden drilling fluid from said scalping deck.

41. A shale shaker as claimed in claim 38, further comprising a scalping deck mounted in said basket above said first screen deck, wherein said first screen deck is adapted to receive said flow of said solids laden drilling fluid from said scalping deck.

42. A shale shaker as claimed in claim 38, wherein each of said first and second screen decks are arranged in said basket at an uphill angle relative to horizontal from a respective feed end to a respective solids discharge end.

43. A method for separating solids from solids laden drilling fluid, the method comprising:

directing a flow of said solids laden drilling fluid to a first screen deck mounted in a basket of a shale shaker;

separating said flow of said solids laden drilling fluid with said first screen deck into a flow of a first solids portion and a flow of a first solids laden drilling fluid portion;

discharging said flow of said first solids portion from a discharge end of said first screen deck;

directing at least part of said flow of said first solids laden drilling fluid portion to a second screen deck mounted in said basket below said first screen deck;

separating said at least said part of said flow of said first solids laden drilling fluid with said second screen deck into a flow of a second solids portion and a flow of a second solids laden drilling fluid portion;

discharging said flow of said second solids portion from a discharge end of said second screen deck;

directing said flow of said second solids laden drilling fluid portion to a sump positioned below said second screen deck;

selectively directing said flow of said first solids portion discharged from said discharge end of said first screen deck to said sump; and

mixing said flow of said first solids portion with said flow of said second solids laden drilling fluid portion.