Paper: Systematic Evaluation And Application Of Capillary StringFoamer Applications For Increased Natural Gas Production

Although the utilization of foaming surfactants (foamers) through down-hole capillary tubing has been used by the industry for a number of years to unload liquids from natural gas wells, there has been marked increase in the application in the past year. This marked increase has resulted, in part, due to improved gas economics, continuing liquid loading problems with onshore gas wells, and improvements in capillary-string installation and foamer technologies. A systematic approach to the evaluation of wells for potential application has been used to improve its success. This evaluation includes the use of a down-hole computer model in conjunction with field and laboratory tests. This paper discusses the approach involved in the evaluation, case studies that demonstrate the success of the evaluation process for the unloading of liquids from gas wells and the treatment of gas wells for salt plugging, and the economic results of the applications.