莺歌海盆地东方区异常高压气井产能分析方法改进  

Improvement on the productivity analysis method of abnormal high pressure gas wells in Dongfang area,Yinggehai basin

作　　者：王磊 WANG Lei(CNOOC China Limited,Zhanjiang Branch,Zhanjiang,Guangdong 524057,China)

机构地区：[1]中海石油(中国)有限公司湛江分公司

出　　处：《中国海上油气》2019年第4期96-101,共6页China Offshore Oil and Gas

基　　金：“十三五”国家科技重大专项“莺琼盆地高温高压天然气富集规律与勘探开发关键技术(编号:2016ZX05024-005)”部分研究成果

摘　　要：针对储层应力敏感和气井产水双重因素困扰莺歌海盆地东方区异常高压气井产能正确认识的问题,利用修正后的考虑储层应力敏感和气水两相渗流能力变化的产气量方程分析了储层应力敏感强度、气井产水量和气相高速非达西流动对气井产能的影响;同时,根据物质平衡理论推导出不考虑水侵的异常高压气藏采出程度计算方程,用于分析储层应力敏感对气藏开发效果的影响。以东方区典型测试出水井为例,分析结果表明:东方区异常高压气藏储层以中等到强应力敏感为主,其主要在气藏开发中后期影响气井产气量和开发效果;地面水气体积比在0.000 1~0.01 m^3/m^3,气井无阻流量随着地面水气体积比的增加急剧下降;气相高速非达西流动对纯气井或产水量较小的气井产能有一定影响。因此,东方区异常高压气井在开发中后期选择合理的生产压差至关重要,并且在开发过程中需要特别注意气井产水的问题。Both reservoir stress sensitivity and water production in gas wells harass the correct understanding on the productivity of abnormal high-pressure gas wells in Dongfang area, Yinggehai basin. To solve this problem, the modified gas production equations considering reservoir stress sensitivity and gas-water two-phase percolation capacity are used to analyze the influences of reservoir stress sensitivity, gas well water production rate and gas phase high-speed non-Darcy flow on gas well productivity;meanwhile, based on the material balance theory, the calculation equation of the abnormal high-pressure gas reservoir without considering water intrusion was derived to analyze the effect of reservoir stress sensitivity on the development of gas reservoirs. Taking the tested typical water producing well in Dongfang area as an example, the analysis results show that the abnormal high-pressure gas reservoirs in Dongfang area are mainly medium to strong stress sensitive, which mainly affects the gas production rate and the development effect of gas wells in the middle-late stages of gas reservoir development;when the surface water-gas volume ratio is among 0.000 1~0.01 m 3/m 3, the unobstructed flowrate of gas wells decreases sharply with the surface water-gas volume ratio. The gas-phase high-speed non-Darcy flow poses a certain impact on the productivity of pure gas wells or gas wells with small water production. Therefore, it is very important to select a reasonable drawdown pressure in the middle -late development stages of abnormal high-pressure gas wells in Dongfang area, and special attention should be paid to the water production in gas wells during the development process.

关 键 词：莺歌海盆地 东方区 异常高压气井 产能分析方法改进 应力敏感 水气体积比 高速非达西渗流 

分 类 号：TE328[石油与天然气工程—油气田开发工程]