Prospect of Production Optimization Challenges of Gas Wells with Liquid Loading Problem Using New Surfactant and Nanotechnology

Abstract

AbstractDecrease 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.Foaming agents provide a means to reduce the density of the liquid so that it can be removed from the well with the gas flow, unloading the accumulated liquid in gas and gas condensate wells. The main constituents of foaming agents are surface active agents. Foam stabilizers are added to increase foam stability. Foaming agent should be selected to form a stable foam under given condition, which means in the presence of salt or sweet water, hydrocarbon phase, at given temperature and pressure.Currently, there are lots of different types of foaming agents. Previous studies mainly focused on the complex between anionic surfactant and anionic surfactant, anionic surfactant and amphoteric ion surfactant, however, the stability of the foam formed by such foaming agents is poor. Therefore, it is necessary to develop a robust foaming agent to cope with the harsh conditions. Traditional research neglect the study of complex between anionic surfactant and cationic surfactant, nevertheless the synergies between them through appropriate method can greatly improve the foam stability compared to one-component system. The strong electrostatic interaction between the opposite charge ionic head groups and the hydrophobic interaction between the hydrocarbon groups made the solution exhibit a complex phase behavior and microstructure which has a high surface activity and foam stability. Gemini surfactant contains a spacer and thus made the packing of molecules tighter and increased the cohesion of surfactant within the monolayer and enhanced the foam stability. Single molecule film formed by surfactant has certain dynamic characteristics, the gas can easily diffuse through the liquid film, so that the bubble burst. However, particles can be adsorbed in the gas/water interface to form a solid film which will reduce the drainage speed of the bubble to enhance the foam stability.In summary, we proposed to develop a robust foaming agent using anionic-nonionic surfactant mixed with gemini cationic surfactant, stabilized by nanoparticles with certain hydrophilicity and size.