Patent ID: 8469103
Filing Date: 2013-06-25
Classification: E21B

Abstract:
1. A method of operating a well having an outer casing and a tubing positioned inside the outer casing, a plunger is moveable within the tubing to periodically draw out a liquid slug, the method comprising: setting a chemical to slug size ratio; monitoring a gas flow rate; shutting-in the well when the gas flow rate drops below a predetermined threshold, the plunger falling to the bottom of the tubing during shut-in; injecting a calculated amount of chemical foaming agent into the tubing after shut-in; determining the size of the liquid slug; opening the well when the casing pressure rises above a predetermined threshold, the plunger being forced to the surface of the well; and wherein said calculated amount of chemical foaming agent is calculated based on one or more previous liquid slug size determinations and the set chemical to slug size ratio.