Apparatus and methods for closing flow paths in wellbores
View Patent ↗A method of closing a fluid flow path in a wellbore is disclosed that in one non-limiting embodiment includes: supplying a flexible structure having a selected shape sufficient to seat on an opening of the fluid flow path, the flexible structure including pores of selected dimensions; determining seating of the flexible structure on the opening of the fluid flow path from a sensor measurement; and supplying a slurry containing a sealant to the flexible structure seated on the opening of the fluid flow path to plug the pores with the sealant to close the fluid flow path.
1. A method of closing a fluid flow path of a casing in a wellbore in a formation, the method comprising:
providing a structure having a first size smaller than the fluid flow path within the casing, wherein the structure expands to a second size that is greater than the fluid flow path when the structure is subjected to a selected condition;
passing the structure through the fluid flow path of the casing to a location outside the casing;
subjecting the structure to the selected condition to expand the structure to the second size; and
allowing a formation fluid to flow from the formation toward the casing to seat the expanded structure in the fluid flow path of the casing to close the fluid flow path.
2. The method of claim 1 , wherein passing the structure through the fluid flow path comprises pumping the structure through the fluid flow path with a fluid and wherein flow back of such fluid enables the expanded structure to close the fluid flow path.
3. The method of claim 1 , wherein the structure includes an expandable core and a degradable encapsulation on the expandable core.
4. The method of claim 3 further comprising pumping a fluid through the fluid flow path configured to degrade the encapsulation.
5. The method of claim 3 , wherein the encapsulation degrades due to one selected from the group consisting of: (i) thermal degradation in the wellbore; (ii) solubility of the encapsulation in fluid present in the wellbore; (iii) corrosion due to the downhole environment; and (iv) subjecting the encapsulation to a selected fluid.
6. The method of claim 1 , wherein passing the structure through the fluid flow path comprises pumping the structure with a fluid though the fluid flow path and enabling the expanded structure to close the fluid flow path comprises a fluid flow back into the fluid flow path.
7. A wellbore system, comprising:
a casing in the wellbore that includes a flow through passage that has been plugged by passing a structure through the flow through passage to a location outside the casing, expanding the structure after it has passed through the flow through passage to a size greater than the size of the flow through passage and allowing a formation fluid to flow from a formation toward the casing to seat the expanded structure in the flow through passage to plug the flow through passage.
8. The apparatus of claim 7 , wherein the structure includes an expandable material.