Unlocking the Potential of Slug Control Deployment Using a Newly Developed Foam Chemical

Abstract The slug flow regime typically forms during multiphase flow in subsurface and surface facilities, which can result in severe flow capacity losses. The foam injection is a proposed method to control and remove slugging in the wellbore and nowadays, the foam application has been extended to controlling the slugging in the pipeline transportation. Prior to a pilot deployment in an offshore Field "S", this study describes a technological assessment review of a newly designed internal foam chemical to control slugging. This application for controlling foam slugs aims to eliminate hydrodynamic slugs that constantly form at Field "S" due to wave instability at gas-liquid flow rates. Based on liquid level trending at surface facilities platform of Field "S", a slug flow regime was observed from severe fluctuation trending. Technology assessment was conducted using inhouse guidelines that aim to shorten overall pilot deployment to initiate testing as early as possible. The laboratory experiment was performed including compatibility tests. The foam stability and interfacial tension (IFT) were carried out using Teclis Foamscan and Grace spinning drop tensiometer, respectively. Meanwhile, the rheology characterization of foam was conducted using a Foam rheometer for the viscosity test. A slug flow regime was discovered based on severe fluctuation trending at surface facilities platform of Field "S" for liquid level trending. Utilizing internal guideline designed to hasten the entire pilot deployment and start testing as soon as possible, technology assessment was done. A pressurized foam Rheometer was used to measure the foam dynamic viscosity, and it measured about 5.2 cP at a shear rate of 1000 s-1. The IFT measured lower than with water and other commercial foamer. When the foam chemical, defoamer, and demulsifier were tested for compatibility with production chemicals such scale inhibitor, corrosion inhibitor, and biocide, neither precipitation nor separation was seen. The recently developed foam chemical may help to further reduce corrosion from 0.17 mm/y to 0.05 mm/y. The technical, operational, health and safety, and environmental major unknown elements of this newly designed technology have all been evaluated and identified. Foam created by foam injection is a main challenge with this method, but it has been overcome by finding the right demulsifier and defoamer. Based on this study, a newly developed foam chemical has been identified as a potential to be deployed in reducing liquid slugging in the pipeline. If slugging can be effectively controlled, value creation will result from an increase in gas and liquid production as well as the avoidance of pipeline maintenance and repair.