钻井液消泡剂研究与应用进展

Progress of Research and Application of Defoamer for Drilling Fluid

油气勘探开发不断向深部复杂地层深入,钻遇的高温、高压及高盐地层环境导致钻井液起泡严重且消泡困难,已成为影响钻井安全的重要因素之一。钻井液中具有表面活性的处理剂在搅动、气侵等情况下易产生气泡,由于钻井液的高黏切、高温下体系中处理剂的化学反应、高p H值等都影响钻井液消泡的效果,造成消泡困难。聚合物钻井液的推广曾削弱了消泡剂的使用,但目前复杂的地层环境和聚磺钻井液的广泛应用迫切需要高效的消泡剂。近年来应用于钻井液的消泡剂主要有有机硅型、非硅型和复配型,聚醚改性有机硅型消泡剂抗温、消泡抑泡效果好,在高温钻井液中有应用前景。消泡效果评价主要是采用高速分散法评价在起泡钻井液中加入消泡剂后泡沫体积的变化。今后钻井液消泡剂研究工作方向主要是,开发新型抗高温消泡剂以进一步提升高温下的抑泡能力,充分利用消泡活性组分之间的协同作用提高性价比,进一步加强其作用机理研究以提高钻井液消泡技术的整体水平。

With the exploration and development of oil and gas to the deep complex formations,the environment of high temperature,high pressure and high salinity results in serious foaming of drilling fluid and being hard to defoam,which has become one of the important factors affecting the drilling safety.The surface active component in drilling fluid is prone to generate bubbles under stirring and injected gas breakthrough.It is pointed out that the main influencing factors of defoaming effect for the drilling fluid are the high viscosi-ty of the drilling fluid,the chemical reaction of additive in the system at high temperature,and the high pH value and so on.The polymer drilling fluid once reduced the use of the defoamers.But efficient defoamer is urgently needed at present because of the complexity of formation and the wide application of polysulfonate drilling fluid.In recent years,the defoamers used in drilling fluid are mainly organosilicon,non-silicone and compounding type.Polyether modified silicone defoamer has high temperature resistance and good defoaming and antifoaming effect,and has application prospect in high temperature drilling fluid.The evaluation of defoaming effect is mainly based on the high speed dispersion method to evaluate the change of foam volume after the defoamers are added into the bubbling drilling fluid.It is pointed out that the main research direc-tion in the future is to develop new high temperature defoamer to further enhance the anti-foaming capacity at high temperature.The synergistic effect among active components of defoamers should be made full use to improve the quality.The research on mechanism should be specially emphasized to improve the whole level of the defoamer for the drilling fluid.