凝析气藏PVT实验数据合格性的判别方法

Distinguishing method for conformity of PVT data for condensate gas reservoirs

黄磊 康凯 张雷 汪跃 吴浩君

中海石油（中国）有限公司天津分公司，天津 300459

Tianjin Branch of CNOOC Ltd., Tianjin 300459, China

PVT数据是初期认识凝析气藏及后续动态跟踪的基础，合格的PVT数据对于凝析气藏的开发具有重要意义。受操作不当或实验设备不干净等因素影响，得到的PVT数据与实际地层烃类物理化学性质会存在偏差。基于恒质膨胀及定容衰竭实验原理，提出3种判别PVT实验结果合格性的方法：1）基于物质平衡原理，推算每级压力下各组分平衡常数，判断定容衰竭实验数据的可靠性；2）根据恒质膨胀及定容衰竭实验的差异性，应用气体状态方程，提出统一化判别方法；3）统计合格PVT样品的实验数据，建立了检验PVT样品合格性的经验图版。针对渤海湾盆地BZ凝析气田PVT样品存在的问题，根据各样品烃类组分物理化学性质，利用文中3种方法对PVT样品实验数据的合格性进行判别，并筛选出合格样品。

The PVT data is the basis for the initial understanding of the condensate gas reservoir and the subsequent dynamic tracking, and the qualified PVT test results are very important for the development of the condensate gas reservoir. Due to the influence of improper operation in the experimental process and unclean experimental equipment, the obtained PVT data will be deviated from the actual physical and chemical properties of hydrocarbon in the formation. Based on the experimental principles of constant mass expansion and constant volume depletion, three methods were proposed to identify the eligibility of PVT results: (1) based on material balance principle, per level pressure equilibrium constants of each composition were calculated, and the reliability of the experimental measured data of constant volume depletion was judged; (2) according to the difference of constant mass expansion and constant volume failure experiments, a unified discriminant method was proposed by using the gas state equation; (3) the experimental data of qualified PVT samples were counted, and the empirical chart of PVT sample qualification was established. In view of the problems existing in PVT samples from BZ condensate gas field in Bohai Sea, according to the physical and chemical properties of hydrocarbon components of each sample, the three methods in this paper are used to discriminate the qualification of experimental data of PVT samples and screen qualified samples.

10.6056/dkyqt202203017