Water shut off method and apparatus
A technique is provided to control flow in subterranean applications, such as hydrocarbon fluid production applications. The technique utilizes an material formed, at least in part, of material that swell in the presence of a specific substance or substances. The material is deployed as a membrane outside a base pipe to desired subterranean locations. Once located, the material allows the flow of hydrocarbon fluids but swells upon contact with the specific substance or substances to limit inflow of undesirable fluids.
1. A method of forming controlling flow of wellbore fluids in a wellbore used in the production of hydrocarbons, comprising:
forming a membrane layer comprising elastomeric material that swell in the presence of an activating substance;
wrapping the strips of membrane layer around a cicumference of a base pipe in contact with wellbore fluids in a manner providing gaps between the wraps, the base pipe comprising one or more radial ports therethrough; and
wherein the strips of the membrance layer expand to cover the one or more radial ports, thereby restricting flow of wellbore fluid through the one or more radial ports when in contact with the activating substance.
2. The method as recited in claim 1 , wherein forming comprises using a material that wells in the presence of water.
3. The method as recited in claim 1 , wherein forming comprises using a material that swell in the presence of preselected chemical agents.
4. The method as recited in claim 1 , wherein forming comprises using a material that swell upon exposure to a fluid with a water content above a given percentage.
5. The method as recited in claim 1 , wherein forming comprises using a material that swells in proportion to the water content of a contacting fluid.
6. The method as recited in claim 1 , further comprising covering the membrane with a coating to delay swelling until removal of the coating at some time after initial placement downhole of the membrane layer.
7. A valve for use in a subterranean wellbore,comprising;
a base pipe having at least one radial port therethorugh;
a membrance comprising two or more strips circumscribling the base pipe in overlapping pattern, the membrance exposed to the wellbore; and
wherein the membrane expands to cover the at least one radial port thereby restricting fluid flow through the port when an activating fluid contacts the membrane.
8. The valve of claim 7 further comprising;
a screen surrounding the pipe, wherein the membrane is positioned between the base pipe and the screen.
9. The valve of claim 7 wherein the activating fluid is water.
10. The valve of claim 7 wherein the activating fluid is a preselected chemical agent.
11. The valve of claim 7 wherein the membrane swells upon exposure to a fluid with a water content above a given percentage.
12. The valve of claim 7 wherein the membrane swells in proportion to the water content of a contacting fluid.
13. The valve of claim 7 wherein the membrane comprises a coated elastomeric base material.
14. A valve for use in a subterranean wellbore, comprising;
a base pipe having at least one radial port therethrough;
a membrane comprising at least one strip poritioned about the base pipe, the membrane exposed to the wellbore;
wherein the membrane expands to cover the at least one radial port thereby restricting fluid flow through port when an activating fluid contacts the membrane; and
wherein the membrane strip is wrapped about the base pipe in a manner providing gaps between the wraps.