新型排水采气用抗凝析油泡排剂

泡沫排水采气是提高低压低产井天然气产量的重要手段之一,但对于含凝析油气井,由于普通泡沫具有遇油消泡的特点,导致常规泡排剂难以产生足量泡沫,从而使排液效果变差。利用阴离子表面活性剂SDS、两性离子表面活性剂CHSB、氟碳表面活性剂PFBS三者的协同作用研制了耐油泡排剂COT。采用罗氏泡沫仪、高温高压可视化泡沫仪、激光共聚焦显微镜研究了凝析油含量、温度、压力和矿化度对泡沫性能的影响,揭示了耐油机理,并与常规泡排剂XA进行了对比研究。研究结果表明,在常压、80℃下,随着凝析油含量的升高,COT泡沫的最大起泡高度(H_max)和半衰期(t_1/2)逐渐升高,而XA的泡沫性能却逐渐减弱;在高压下,随着温度升高,COT泡沫的H_max不受影响,但t_1/2却逐步下降。当固定温度时,随着压力升高,COT泡沫的H_max和t_1/2均显著提升,且在相同的压力和温度下,COT的泡沫综合性能优于XA;随着矿化度升高,COT泡沫的H_max略微下降,t_1/2<...

A new anti-condensate foaming agent for drainage gas recovery

Foam drainage gas recovery is one of the important means to increase the gas production of low-pressure and low-production wells. However, defoaming occurs when foams encounter oil in condensate-bearing gas wells, so it is difficult for conventional foaming agent to generate sufficient foams, which makes the drainage effect worse. The oil-resistant foaming agent COT was developed using the synergistic effect of the anionic surfactant SDS, the zwitterionic surfactant CHSB, and the fluorocarbon surfactant PFBS. Using a ROSS-Miles foam meter, a high-temperature and high-pressure visual foam meter, and a laser scanning confocal microscope, the effect of condensate content, temperature, pressure, and salinity on foam performance was studied, and the mechanism of oil resistance was revealed. Furhter, a comparative study is performed between COT and the conventional foaming agent XA. The results show that at normal pressure and 80℃, the maximum foaming height (H_max)and half-life time (t_1/2)of COT foam gradually increased with the increasing condensate content, while the foam performance of XA gradually weakened. Under high pressure, as the temperature increased, the H_max of COT foam was not changed, but t_1/2 gradually decreased. When the temperature was fixed, with the increasing of pressure, the H_max and t_1/2 of COT foam increased significantly, and the comprehensive performance of COT foam was superior to XA under the same pressure and temperature. With the increasing of salinity, the H_max of COT foam decreased slightly, but t_1/2 increased significantly. By studying the interaction between the oil droplets and the foam film, it is found that when the oil droplets contact with the COT foam film, a stable pseudoemulsion film is formed preventing the oil droplets from continuing to penetrate, thereby forming stable and oil-resistant foams. The foaming agent developed based on the above-mentioned laboratory research has been applied in 12 gas wells in the field, with the cumulative gas production increased by 26.35×10⁴m³.