海上生产气井动态产能评价新方法  

A new method for dynamic productivity evaluation of offshore gas wells

作　　者：洪舒娜 秦峰 陈斯宇 白美丽 HONG Shuna;QIN Feng;CHEN Siyu;BAI Meili(CNOOC China Litmited,Shenzhen Branch,Guangdong Shenzhen 518000,China)

机构地区：[1]中海石油(中国)有限公司深圳分公司,广东深圳518000

出　　处：《非常规油气》2021年第6期60-67,共8页Unconventional Oil & Gas

基　　金：中海油有限公司综合科研项目“南海东部油田上产2 000万t关键技术研究”(CNOOC-KJ 135 ZDXM 37 SZ)。

摘　　要：针对海上生产气井生产过程中因生产压力及测试成本无法开展实时产能评估的问题,基于不稳定试井理论及二项式产能方程,分析了引起产能变化的参数,推导并建立了适用于海上的在生产气井动态产能评价方法。研究结果表明:1)对于定容或弱水驱气藏、无污染气井,天然气黏度和偏差因子是引起产能衰减的主要原因;2)对于中强水驱气藏、无污染气井,除天然气性质参数外,生产时长、气藏综合压缩系数及非达西流系数均会引起产能变化;3)若气井存在污染,表皮系数也不可忽略,需经不断地调整拟合后确定。经实际应用,该方法计算地层压力与实测值差别在1%以内,计算结果可靠,对气井合理配产有较好的指导意义。The productivity of offshore gas wells during producing time are difficult to determine because of the production stress and testing costs.In order to deal with the problem, based on the transient well test theory and binomial productivity equation, by analyzed the parameters that cause the productivity change, a new method for calculating dynamic productivity is proposed for the offshore gas wells.The results show that: 1)The gas viscocity and deviation factor are the main reason caused the productivity attenuation for constant or weak water-drive gas reservoirs whitch have no pollution;2)Except for gas property parameters, production time, gas reservoir comprehensive compressibility coefficient and non-darcy flow coefficient all lead to productivity varation for medium or strong water-drive gas reservoirs;3)If the reservoirs have pollution, the skin factor could not be ignored.It is determined by continuous adiustenmt and fitting.The example application showed that the difference between calculated formation static pressure by using the new method and the measured value is less than 1%.The calculated results are reliable and have a good guiding significance for reasonable production allocation of gas wells.

关 键 词：动态产能 气井 水驱气藏 不稳定流动 

分 类 号：TE37[石油与天然气工程—油气田开发工程]