Decrease of gas production is an indicator that liquid column is probably building up in the well and an additional energy is required to lift the liquid out should be applied to control this situation. Commonly used methods include rod pumps, gas lift, plunger lift, foaming agents, alternate flow/shut-in periods, the use of smaller diameter production tubing and swabbing.

A method has been developed to guide operations managers, engineers and technicians responsible for operations when foaming agents are chosen to provide unloading of accumulated liquid in gas and gas condensate wells.

Depending on the well conditions, surface pressure test data and field surveys data, using different foam agents (sticks and/or liquid), the suitable intermittent system can be selected. Very often the combined production system (intermittent operation combined with launching foam sticks) or only intermittent operation using motor valve or plunger lift has been chosen.

Considering that application of foaming agent essentially promotes gas lift effect to sweep the fluids out of the tubing by adjusting some input parameters, one can simulate an apparent foamed flowing gradient. To select the appropriate correction of calculated holdup factor by using any NODAL software package, the gradients comparison was used for a rough estimation of the modified flowing gradient in the typical application.

The method proposed actions necessary to start foaming agent application. Each step and parameters affecting the process efficiency have been discussed in details. Several case studies have been discussed to confirm the validity of the proposed method.

You can access this article if you purchase or spend a download.