大庆油田环空带压气井治理措施技术研究

Technical research on treatment measures for gas wells with annular pressure in Daqing Oilfield

徐深气田具有井深、高温、含CO_(2)的特点,由于地质工况复杂,部分气井管柱失效导致持续环空带压,存在高压气体泄漏甚至气井失控风险,造成气井无法正常生产,产气量降低,而且对气田井控安全造成极大隐患。针对这一问题,开展了气井环空带压途径及防治措施研究,对于中、低风险井,明确推荐工作压力、提示最大允许压力、警告最大极限压力,通过对环空带压值的分级判断,确保环空带压气井的运行可控;对于高风险井形成了环空带压气井治理工艺技术。该技术在大庆油田气井进行了71井次的成功应用,措施治理之后消除了环空带压,保障了气井正常生产。该技术的应用有效保障了大庆徐深火山岩储层环空带压气井的安全运行。

The Xushen gas field has the characteristics of deep well,high temperature and containing CO_(2).Due to the complex geological conditions,the failure of some gas well strings has led to continuous pressure in annulus,and there existed risks of high-pressure gas leakage and even out-of-control for gas wells,causing the abnormal production and reducing the gas yield in gas wells.Moreover,it would cause great hidden dangers to the safety of well control in gas field.In order to solve the problem,the research on pathway and treatment measures for gas wells with annular pressure has been carried out.For the medium and low risk wells,the working pressure is clearly recommended;the maximum allowable pressure is indicated;and the maximum limit pressure is warned.Classifying and judging the pressure grade value in annulus can ensure the controllable operation for gas wells with annular pressure.For the high risk wells,the treatment technology for gas wells with annulus pressure in has been formed.The technology has been successfully applied to 71 times in gas wells of Daqing Oilfield.After the treatment measures,the annular pressure was eliminated to ensure the normal production of gas wells.The application of the technology effectively guarantees the safe operation for gas wells with annular pressure in Xushen volcanic reservoirs of Daqing Oilfield.