Systems & methods for the recovery of lost circulation & similar material

• US 20100089802A1
• Filed: 10/10/2008
• Published: 04/15/2010
• 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
• Granted Patent: US 8,113,356 B2
• Time in Patent Office: Days
• US Class Current: 209/360
• CPC Class Codes: B07B 1/46 Constructional details of screens in general; Cleaning or heating of screens
• 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

Methods and systems are disclosed employing a quad-tier shale shaker for processing a mixture of drilling fluid and solids which solids include, in one aspect, lost circulation material (and/or material of size similar to the size of the lost circulation material). This abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure and is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims, 37 C.F.R. 1.72(b).

Claims

1. A system for processing a mixture of drilling fluid and solid material to separate at least one component of the mixture by size from the mixture, the system comprising

a vibratable basket,

a sump at a bottom of the basket,

a plurality of spaced-apart screens including a first screen deck, a second screen deck positioned below the first screen, a third screen deck positioned below the second screen deck, and a fourth screen deck positioned below the third screen,

the screens mounted in the vibratable basket and vibratable therewith,

the first screen deck having screen mesh of a first size to remove from a top of the first screen deck solids from the mixture with a largest dimension equal to and larger than a first dimension so that material with a largest dimension smaller than the first dimension is passable down through the first screen deck,

the second screen deck having screen mesh of a second size to remove from a top of the second screen solids from the mixture passing to the second screen deck from the first screen deck which have a largest dimension equal to or larger than the second size so that material with a largest dimension smaller than the second size is passable down through the second screen deck, material and fluid passing through the second screen deck comprising a secondary flow,

diversion apparatus connected to the basket positioned for providing at least a portion of the secondary flow to the third screen deck and, selectively, a portion of the secondary flow to the fourth screen deck,

the third screen deck having screen mesh of a third size, and the fourth screen deck having screen mesh of a fourth size for removing solids from the secondary flow on the top of the third screen deck and from the top of the fourth screen deck, and

drilling fluid flowing through the first screen deck, the second screen deck and one of the third screen deck and fourth screen deck flowing down into the sump.

2. The system of claim 1 wherein the first screen deck is a scalping deck.

3. The system of claim 1 wherein the screen mesh of a second size is suitable for removing solids the size of lost circulation material.

4. The system of claim 3 wherein the screen mesh of a second size permits pieces 1/16 inch in largest dimension or smaller to pass through.

5. The system of claim 4 wherein the pieces include graphite balls.

6. The system of claim 3 wherein the solids include pieces of lost circulation material and pieces of material other than lost circulation material.

7. The system of claim 3 wherein

the drilling fluid mixture introduced to the system to be treated by the system includes a first amount of lost circulation material,

the second deck is able to remove a second amount of lost circulation material, and

the second amount at least 75% of the first amount.

8. The system of claim 3 wherein

the drilling fluid mixture introduced to the system to be treated by the system includes a first amount of lost circulation material,

the second deck is able to remove a second amount of lost circulation material, and

the second amount at least 95% of the first amount.

9. The system of claim 6 further comprising

reclamation apparatus for receiving the lost circulation material.

10. The system of claim 9 further comprising

auger apparatus for moving the lost circulation material with respect to the reclamation apparatus.

11. A system for processing a mixture of drilling fluid and solid material to separate at least one component of the mixture by size from the mixture, the system comprising

a vibratable basket,

a sump at a bottom of the basket,

a plurality of spaced-apart screens including a first screen deck, a second screen deck positioned below the first screen, a third screen deck-positioned below the second screen deck, and a fourth screen deck positioned below the third screen,

the screens mounted in the vibratable basket and vibratable therewith,

the first screen deck having screen mesh of a first size to remove from a top of the first screen solids from the mixture with a largest dimension equal to and larger than a first dimension so that material with a largest dimension smaller than the first dimension is passable down through the first screen deck,

the second screen deck having screen mesh of a second size to remove from a top of the second screen solids from the mixture passing to the second screen deck from the first screen deck which have a largest dimension equal to or larger than the second size so that material with a largest dimension smaller than the second size is passable down through the second screen deck, material and fluid passing through the second screen deck comprising a secondary flow,

diversion apparatus connected to the basket positioned for providing at least a portion of the secondary flow to the third screen deck and, selectively, a portion of the secondary flow to the fourth screen deck,

the third screen deck having screen mesh of a third size, and the fourth screen deck having screen mesh of a fourth size for removing solids from the secondary flow on the top of the third screen deck and from the top of the fourth screen deck,

drilling fluid flowing through the first screen deck, the second screen deck and one of the third screen deck and fourth screen deck flowing down into the sump,

wherein the first screen deck is a scalping deck,

wherein the screen mesh of a second size is suitable for removing solids the size of lost circulation material, said solids including pieces of lost circulation material and pieces of material other than lost circulation material,

the drilling fluid mixture introduced to the system to be treated by the system includes a first amount of lost circulation material,

the second deck is able to remove a second amount of lost circulation material,

the second amount at least 75% of the first amount, and

reclamation apparatus for receiving the lost circulation material.

12. A system for processing a mixture of drilling fluid and solid material to separate at least one component of the mixture by size from the mixture, the system comprising

a vibratable basket,

a sump at a bottom of the basket,

a plurality of spaced-apart screens including a first screen deck, a second screen deck positioned below the first screen, a third screen deck positioned below the second screen deck, and a fourth screen deck positioned below the third screen,

the screens mounted in the vibratable basket and vibratable therewith,

the first screen deck having screen mesh of a first size to remove from a top of the first screen deck solids from the mixture with a largest dimension equal to and larger than a first dimension so that material with a largest dimension smaller than the first dimension is passable down through the first screen deck in a primary flow,

the second screen deck having screen mesh of a second size to remove from a top of the second screen solids from the mixture passing to the second screen deck from the first screen deck which have a largest dimension equal to or larger than the second size so that material with a largest dimension smaller than the second size is passable down through the second screen deck,

diversion apparatus connected to the basket positioned for providing at least a portion of the primary flow to the second screen deck and a portion of the primary flow to the third screen deck,

the third screen deck having screen mesh of a third size, and the fourth screen deck having screen mesh of a fourth size for removing from flow thereto solids from on the top of the third screen deck and from on the top of the fourth screen deck, and

drilling fluid flowing through the first screen deck, and one of the second screen deck and the third screen deck flowing down into the sump.

13. The system of claim 12 wherein the first screen deck is a scalping deck.

14. The system of claim 12 wherein the screen mesh of a second size is suitable for removing solids the size of lost circulation material.

15. The system of claim 14 wherein the screen mesh of a second size permits pieces 1/16 inch in largest dimension or smaller to pass through.

16. The system of claim 14 wherein the solids include pieces of lost circulation material and pieces of material other than lost circulation material.

17. The system of claim 14 wherein

the drilling fluid mixture introduced to the system to be treated by the system includes a first amount of lost circulation material,

the second deck is able to remove a second amount of lost circulation material, and

the second amount at least 75% of the first amount.

18. A method for treating a mixture of drilling fluid and solid material to separate at least one component of the mixture by size from the mixture, the method comprising

feeding the mixture to a vibratable basket of a system, the system comprising a sump at a bottom of the basket, a plurality of spaced-apart screens including a first screen deck, a second screen deck positioned below the first screen, a third screen deck positioned below the second screen deck, and a fourth screen deck positioned below the third screen, the screens mounted in the vibratable basket and vibratable therewith, the first screen deck having screen mesh of a first size to remove from a top of the first screen deck solids from the mixture with a largest dimension equal to and larger than a first dimension so that material with a largest dimension smaller than the first dimension is passable down through the first screen deck, the second screen deck having screen mesh of a second size to remove from a top of the second screen solids from the mixture passing to the second screen deck from the first screen deck which have a largest dimension equal to or larger than the second size so that material with a largest dimension smaller than the second size is passable down through the second screen deck, material and fluid passing through the second screen deck comprising a secondary flow, diversion apparatus connected to the basket positioned for providing at least a portion of the secondary flow to the third screen deck and, selectively, a portion of the secondary flow to the fourth screen deck, the third screen deck having screen mesh of a third size, and the fourth screen deck having screen mesh of a fourth size for removing solids from the secondary flow on the top of the third screen deck and from the top of the fourth screen deck, and the method further comprising

flowing drilling fluid through the first screen deck, the second screen deck and one of the third screen deck and fourth screen deck flowing down into the sump.

19. The method of claim 18 wherein the screen mesh of a second size is suitable for removing solids the size of lost circulation material, the method further comprising

removing solids with the second deck, the solids the size of lost circulation material.

20. A method for treating a mixture of drilling fluid and solid material to separate at least one component of the mixture by size from the mixture, the method comprising

feeding the mixture to a vibratable basket of a system, the system comprising a sump at a bottom of the basket, a plurality of spaced-apart screens including a first screen deck, a second screen deck positioned below the first screen, a third screen deck positioned below the second screen deck, and a fourth screen deck positioned below the third screen, the screens mounted in the vibratable basket and vibratable therewith, the first screen deck having screen mesh of a first size to remove from a top of the first screen deck solids from the mixture with a largest dimension equal to and larger than a first dimension so that material with a largest dimension smaller than the first dimension is passable down through the first screen deck in a primary flow, the second screen deck having screen mesh of a second size to remove from a top of the second screen solids from the mixture passing to the second screen deck from the first screen deck which have a largest dimension equal to or larger than the second size so that material with a largest dimension smaller than the second size is passable down through the second screen deck, diversion apparatus connected to the basket positioned for providing at least a portion of the primary flow to the second screen deck and a portion of the primary flow to the third screen deck, the third screen deck having screen mesh of a third size, and the fourth screen deck having screen mesh of a fourth size for removing from flow thereto solids from on the top of the third screen deck and from on the top of the fourth screen deck, and the method further comprising

flowing drilling fluid through the first screen deck, and one of the second screen deck and the third screen deck flowing down into the sump.