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The present invention generally relates to a method and an apparatus for selectively isolating a portion of a wellbore. In one aspect, an apparatus for isolating a zone in a wellbore is provided. The apparatus includes a body having a bore. The apparatus further includes a first flapper member and a

The present invention generally relates to a method and an apparatus for selectively isolating a portion of a wellbore. In one aspect, an apparatus for isolating a zone in a wellbore is provided. The apparatus includes a body having a bore. The apparatus further includes a first flapper member and a second flapper member, each flapper member selectively rotatable between an open position and a closed position. Additionally, the apparatus includes a flapper latch assembly disposed in the bore, the flapper latch assembly movable between an unlocked position and a locked position, wherein the flapper latch assembly is configured to hold the first flapper member in the closed position when the flapper latch assembly is in the locked position. In another aspect, a method for selectively isolating a zone in a wellbore is provided. In yet a further aspect, a flapper latch assembly for use with a flapper valve is provided.

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The invention claimed is: 1. An apparatus for isolating a zone in a wellbore, the apparatus comprising: a body having a bore; a first flapper member and a second flapper member disposed in the bore, each flapper member selectively rotatable between an open position and a closed position multiple ti

The invention claimed is: 1. An apparatus for isolating a zone in a wellbore, the apparatus comprising: a body having a bore; a first flapper member and a second flapper member disposed in the bore, each flapper member selectively rotatable between an open position and a closed position multiple times, wherein the first flapper member is rotated from the open position to the closed position in a first direction and the second flapper member is rotated from the open position to the closed position in a second direction, wherein the first flapper member is operable to move to the open position after the second flapper member is in the open position; and a flapper latch assembly disposed in the bore, the flapper latch assembly movable between an unlocked position and a locked position, wherein the flapper latch assembly is configured to hold the first flapper member in the closed position when the flapper latch assembly is in the locked position. 2. The apparatus of claim 1, wherein the flapper latch assembly includes a latch body, a pin member, and a biasing member. 3. The apparatus of claim 2, wherein the biasing member causes the latch body to rotate around the pin member as the flapper latch assembly moves between the unlocked position and the locked position. 4. The apparatus of claim 3, wherein the flapper latch assembly is biased in the locked position. 5. The apparatus of claim 1, wherein the flapper latch assembly is moved from the unlocked position to the locked position when the flapper latch assembly is moved relative to the body into a recess formed in the bore of the body. 6. The apparatus of claim 5, wherein the flapper latch assembly is moved from the locked position to the unlocked position when the flapper latch assembly is moved out of the recess formed in the bore of the body. 7. The apparatus of claim 1, wherein the flapper latch assembly includes a release mechanism that is configured to allow the first flapper member to move from the closed position to the open position when the flapper latch assembly is in the locked position. 8. The apparatus of claim 7, wherein the release mechanism includes a shearable member. 9. The apparatus of claim 1, wherein the first direction is opposite the second direction. 10. The apparatus of claim 1, further including an upper sub and a lower sub attached to the body, whereby the first flapper member moves to the closed position toward the upper sub and the second flapper member moves to the closed position toward the lower sub. 11. A method for selectively isolating a zone in a wellbore, the method comprising: positioning a downhole tool in the wellbore, the downhole tool having a body, a first flapper member, a second flapper member, and a flapper latch assembly, whereby each flapper member is initially in an open position while positioning; moving the first flapper member to a closed position by rotating the first flapper member in a first direction; moving the second flapper member to a closed position by rotating the second flapper member in a second direction; moving a flapper latch assembly from an unlocked position to a locked position, whereby the flapper latch assembly is configured to hold the first flapper member in the closed position when the flapper latch assembly is in the locked position; and moving the flapper latch assembly relative to the body and into a recess formed in the body, thereby allowing the flapper latch assembly to move from the unlocked position to the locked position. 12. The method of claim 11, wherein a latch body of the flapper latch assembly rotates around a pin member as a result of moving the flapper latch assembly into the recess. 13. The method of claim 11, further comprising moving the flapper latch assembly out of the recess formed in the body, thereby allowing the flapper latch assembly to move from the locked position to the unlocked position. 14. The method of claim 11, further comprising activating a release mechanism in the flapper latch assembly, thereby allowing the first flapper member to move from the closed position to the open position when the flapper latch assembly is in the locked position. 15. The method of claim 11, further comprising shearing a shearable member in the flapper latch assembly, thereby allowing the first flapper member to move from the closed position to the open position when the flapper latch assembly is in the locked position. 16. A flapper latch assembly for use with a flapper valve, the flapper latch assembly comprising: a body rotatable between an unlocked position and a locked position, wherein the body includes an end configured to engage a portion of the flapper valve when the flapper valve is in a closed position and the body is in the locked position; a biasing member attached to the body, wherein the biasing member is configured to bias the body in the locked position; and a release mechanism that is configured to allow the flapper valve to move from the closed position to an open position when the body is in the locked position. 17. The flapper latch assembly of claim 16, wherein the release mechanism includes a shearable member. 18. An apparatus for isolating a zone in a wellbore, the apparatus comprising: a body having a bore; a first flapper member and a second flapper member disposed in the bore, each flapper member selectively rotatable between an open position and a closed position multiple times, wherein the first flapper member is rotated from the open position to the closed position in a first direction and the second flapper member is rotated from the open position to the closed position in a second direction; and a flapper latch assembly disposed in the bore, the flapper latch assembly movable between an unlocked position and a locked position, wherein the flapper latch assembly is configured to hold the first flapper member in the closed position when the flapper latch assembly is in the locked position, wherein the flapper latch assembly includes a latch body, a pin member, and a biasing member, wherein the biasing member causes the latch body to rotate around the pin member as the flapper latch assembly moves between the unlocked position and the locked position. 19. An apparatus for isolating a zone in a wellbore, the apparatus comprising: a body having a bore; a first flapper member and a second flapper member disposed in the bore, each flapper member selectively rotatable between an open position and a closed position multiple times, wherein the first flapper member is rotated from the open position to the closed position in a first direction and the second flapper member is rotated from the open position to the closed position in a second direction; and a flapper latch assembly disposed in the bore, the flapper latch assembly movable between an unlocked position and a locked position, wherein the flapper latch assembly is configured to hold the first flapper member in the closed position when the flapper latch assembly is in the locked position, wherein the flapper latch assembly is moved from the unlocked position to the locked position when the flapper latch assembly is moved relative to the body into a recess formed in the bore of the body. 20. A method for selectively isolating a zone in a wellbore, the method comprising: positioning a downhole tool in the wellbore, the downhole tool having a body, a first flapper member, a second flapper member, and a flapper latch assembly, whereby each flapper member is initially in an open position; moving the first flapper member to a closed position by rotating the first flapper member in a first direction; moving the second flapper member to a closed position by rotating the second flapper member in a second direction; moving a flapper latch assembly from an unlocked position to a locked position, whereby the flapper latch assembly is configured to hold the first flapper member in the closed position when the flapper latch assembly is in the locked position; and shearing a shearable member in the flapper latch assembly, thereby allowing the first flapper member to move from the closed position to the open position when the flapper latch assembly is in the locked position. 21. An apparatus for locking and unlocking a flapper valve, comprising: a body; a pin member coupled to the body; a shearable release mechanism coupled to the body; and a biasing member configured to rotate the body around the pin member to thereby position the shearable release mechanism into engagement with a portion of the flapper valve. 22. The apparatus of claim 21, wherein the biasing member is configured to rotate the body into a first position to lock the flapper valve in a closed position. 23. The apparatus of claim 22, wherein the release mechanism is configured to allow the flapper valve to move from the closed position to an open position while the body is in the first position. 24. The apparatus of claim 21, further comprising a housing, wherein the body is disposed in and movable relative to the longitudinal axis of the housing. 25. The apparatus of claim 24, where the body is rotatable around the pin member by the biasing member when the body is moved relative to the housing into a recess formed in the housing. 26. The apparatus of claim 25, wherein the body is rotatable around the pin member by the housing when the body is moved out of the recess formed in the housing to thereby position the release mechanism out of engagement with the portion of the flapper valve. 27. A method for locking and unlocking a flapper valve, comprising: positioning a flapper valve and a latch assembly in a housing; closing the flapper valve; moving the latch assembly and the flapper valve relative to the longitudinal axis of the housing; and locking the flapper valve in a closed position with the latch assembly by moving the latch assembly into a recess formed in the housing. 28. The method of claim 27, further comprising unlocking the flapper valve from engagement with the latch assembly by moving the latch assembly out of the recess formed in the housing to permit the flapper valve to move into an open position. 29. The method of claim 27, further comprising rotating a body of the latch assembly into engagement with the flapper valve to lock the flapper valve in the closed position. 30. The method of claim 29, further comprising positioning a release mechanism of the latch assembly into engagement with the flapper valve to lock the flapper valve in the closed position. 31. The method of claim 30, further comprising actuating the release mechanism to permit the flapper valve to move into an open position while the body remains in a rotated position. 32. The method of claim 31, wherein actuating the release mechanism comprises shearing a shearable member. 33. The method of claim 27, further comprising holding the flapper valve in an open position with a first member and moving the first member from engagement with the flapper valve to permit closing of the flapper valve. 34. The method of claim 33, wherein the first member is a flow tube that is movable through the flapper valve. 35. The method of claim 27, further comprising rotating a body of the latch assembly with a biasing member by moving the body into the recess of the housing to lock the flapper valve in the closed position. 36. The method of claim 27, further comprising rotating a body of the latch assembly with the housing by moving the body out of the recess of the housing to unlock the flapper valve and permit the flapper valve to move into an open position. 37. A method for locking and unlocking a flapper valve, comprising: positioning a flapper valve and a latch assembly in a housing; holding the flapper valve in an open position with a first member and moving the first member from engagement with the flapper valve to permit closing of the flapper valve; closing the flapper valve; and locking the flapper valve in a closed position with the latch assembly by moving the latch assembly into a recess formed in the housing. 38. The method of claim 37, wherein the first member is a flow tube that is movable through the flapper valve. 39. A method for locking and unlocking a flapper valve, comprising: positioning a flapper valve and a latch assembly in a housing; closing the flapper valve; locking the flapper valve in a closed position with the latch assembly by moving the latch assembly into a recess formed in the housing; and rotating a body of the latch assembly with a biasing member by moving the body into the recess of the housing to lock the flapper valve in the closed position. 40. A method for locking and unlocking a flapper valve, comprising: positioning a flapper valve and a latch assembly in a housing; closing the flapper valve; locking the flapper valve in a closed position with the latch assembly by moving the latch assembly into a recess formed in the housing; and rotating a body of the latch assembly with the housing by moving the body out of the recess of the housing to unlock the flapper valve and permit the flapper valve to move into an open position.