Patent ID: 11879308
Assignee: EXXONMOBIL TECHNOLOGY AND ENGINEERING COMPANY
Field: Civil engineering (Other fields)
Classification: CPC E  F | IPC E

Claim 9:
10. A method for in-situ application of a coating agent to a production tubing within a wellbore using a plunger lift system, comprising:
closing a surface valve to halt fluid flow from the wellbore;
pressurizing the production tubing to displace fluids within the production tubing to below a bumper spring positioned toward a bottom of the production tubing;
maintaining the pressure on the production tubing to prevent fluid inflow into the production tubing;
dropping a first plunger from a surface into the production tubing such that the first plunger travels toward a bottom of the production tubing until landing on the bumper spring;
pumping a predetermined amount of the coating agent from the surface into the production tubing such that the coating agent flows to the bottom of the production tubing and settles on top of the first plunger;
dropping a second plunger from the surface into the production tubing such that the second plunger travels toward the bottom of the production tubing and acts as a cap for the coating agent;
opening the surface valve to enable a differential pressure between the production tubing and an annulus of the wellbore to drive the first plunger, the coating agent, and the second plunger to the surface in a manner that provides for in-situ application of the coating agent to an inner diameter of the production tubing;
repressurizing the production tubing to prevent fluid inflow into the production tubing; and
allowing the coating agent to dry/cure for a predetermined drying/curing time.