CHEMICALLY TARGETED CONTROL OF DOWNHOLE FLOW CONTROL DEVICES

摘要

Systems and methods using enhanced flow control devices are described. The flow control devices can be selectively closed completely or have its effective flow area reduced to restrict production (or injection) by use of a chemical trigger mechanism. In addition, some of the systems described herein deploy specific targeted chemical tracers, dissolvable in the unwanted production fluid (e.g. water or gas). These chemical tracers once dissolved will enter the production stream and be identified at the surface. The identification will determine which segment of the completion is producing the unwanted fluid. According to some embodiments, an appropriate chemical trigger is placed, for example, by pumping down through the tubing and utilizing intelligent completion valve to place the chemical, or by spotting with coiled tubing and bullhead to the formation, or by other methods of chemical placement. The chemical trigger will only trigger the active chemical in the appropriate flow control device. This chemical will then change state—dissolve, create thermal reaction, create a pressure swell or expand—which in turn allows a mechanical device to shift position such that a valve in the flow control device closes, or reduces its flow by restricting the flow area by swelling/expansion of the active chemical.

主权项

1. A method of chemically targeting control of flow control devices installed in a wellbore comprising:
by an operator, selecting for actuation at least one of a plurality of flow control devices previously installed in a wellbore, leaving at least one of said plurality of flow control devices as non-selected for actuation; selecting a triggering chemical fluid configured to selectively trigger actuation of said flow control devices selected for actuation and configured not to trigger actuation of said flow control devices non-selected for actuation; flowing said selected triggering chemical fluid from a surface location through the wellbore and to expose both said flow control devices selected for actuation and said flow control devices non-selected for actuation to said triggering chemical fluid; selectively triggering actuations of said flow control devices selected for actuation, said actuations being caused by one or more chemical reactions resulting from exposure with said triggering chemical fluid, leaving un-actuated said flow control devices non-selected despite being exposed to said triggering chemical fluid.