Slow-releasing foam sticks based on degradable polymer nanocomposite for gas well deliquification

Abstract

Conventional foam sticks release surfactant too rapidly, resulting in a short foam duration during gas well deliquification, especially at elevated temperatures. This necessitates frequent addition of foam sticks to sustain foaming and open the wellhead. To address this issue, this paper explores the utilization of a degradable polymer and inorganic nanoparticles composite to encapsulate surfactant for prolonged and controlled release of foam, particularly at high temperatures. The nanocomposite foam sticks were prepared by blending molten degradable polymer with surfactant and various inorganic nanoparticles, which were subsequently injected and solidified in molds. The release performance of the foam sticks was evaluated based on foaming performance and surface activity over time. The nanocomposite foam sticks were characterized by infrared spectroscopy (IR), scanning electronic microscopy (SEM), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Characterization of the nanocomposite showed homogenous surfactant incorporation and increased thermostability of the solid foam sticks in the presence of inorganic nanoparticles. The foam release performance was optimized for the composite comprising the polymer, surfactant and inorganic nanoparticle fillers. The optimized nanocomposite encapsulated surfactant demonstrated controlled surfactant release, sustaining foam for over 96 h at 130 °C in brine solution. The study presents an innovative approach to enhance gas well productivity, offering a sustainable and environmentally friendly solution to the challenges of deliquification in gas wells.