Tight and marginal gas reservoirs often produce lower than their actual potential due to severe load up issues, and if not treated it can lead to loss in reserves as well. Traditional methods used to address this issue in the wellbore include plunger lift, pumping units, and re-circulation, but with declining reservoir pressures, these methods become less effective and often times the expense of a pumping unit cannot be economically supported by the well.
In these circumstances, an efficient & cost-effective solution to alleviate the above mentioned problems is to apply capillary soap injection process, which eliminates liquid loading and revive the production of such wells. The swift payout and generally low risk to reward nature of the spent are destined to propel rapid expansion of Foam Injection Technology for Deliquification of Gas Wells.
In this system, chemical surfactants in conjunction with well's gas flow is utilized to adapt the apparent density and surface tension of its produced liquids in an endeavor to lower the system's critical velocity. This method not only results in revival of the well and sizeable increase in production of gas but also extends the well life and economic recovery when compared with gas lift and plunger lift.
This paper presents the comprehensive strategy of application of capillary injection process in marginal and tight gas reservoirs of USA; from diagnostics to the successful execution of any endeavor involving production enhancement & prolonging lives of dying wells using foam injection. Real field case study and results from both the lab & field have been incorporated, coupled with the recommendations for the future ventures of similar nature in which sales revenue augmented to around 200–1000 $/day, production of gas augmented to around 40–1000 MCFD and the payback period was noted to vary from 5–60 days. The paper would also draw attention to its application in Pakistan where this process resulted in incremental production of 1 MMSCFD gas from three wells.