Study on anionic-cationic surfactant compound foaming agent

In order to solve the serious problem of liquid loading in gas wells, we chose the compound foaming agent system with synergistic effect by anion and cation surfactant mixed system, and the characteristics of vesicles formation which increases foam stability, and developed a novel type of foaming agent for water drainage of gas wells. Through orthogonal experiments, the optimum two groups of compound foaming agent system components and their proportions were determined. We also studied the effect of NaCl and CaCl2 on the properties of the systems, and the dynamic liquid carrying capacity. It is found that when the carbon chain length is 16, the synergistic effect is the best, and the optimal mixture ratio of the system I is SDS: JS: JT-3=4﹕3﹕2, while the optimal mixture ratio of the system II is SDS: AOS: JS: JT-3=1:2:2:2. At the same time, it is also found that the foam viscosity of the complex system will increase relatively in a certain concentration of NaCl, and the stability of foam is also increased. But it is easy to precipitate in the condition of CaCl2, and the foam performance will be worse. Through experimental evaluation, the mixed system shows better salt resistance and liquid carrying capacity, and is good for foam drainage of gas wells, with wide application potential.