气液两相状态下的凝析气井产能评价新方法  

A new deliverability evaluation method of gas condensate wells in gas–liquid two-phase state

作　　者：陆家亮[1] 张皓 常宝华[1] 曹雯[1] 孙贺东[1] Lu Jialiang1, Zhang Hao2,3, Chang Baohua1, Cao Wen1 , Sun Hedong1(1. PetroChina Research Institute of Petroleum Exploration ＆ Development, Langfang, Hebei 065007, China; 2.University of Chinese Academy of Sciences, Beijing 100049, China; 3. Institute of Porous Flow and Fluid Mechanics, Langfang, Hebei 065007, Chin)

机构地区：[1]中国石油勘探开发研究院 [2]中国科学院大学 [3]中国科学院渗流流体力学研究所

出　　处：《天然气工业》2018年第4期111-116,共6页Natural Gas Industry

基　　金：中国石油天然气股份有限公司重大科技专项"深层油气勘探开发关键技术研究"(编号:2014E-3203)

摘　　要：凝析气藏地层中产生油气两相渗流后,对气井的产能测试数据进行分析时,常出现二项式产能方程的系数B为负数的异常情况,难以有效评价气井的产能,进而影响对气井生产动态的准确预测。为此,基于拟单相渗流方程和油气两相渗流方程,在气井的流动达到拟稳定阶段后,建立了拟单相稳定点产能评价方法(以下简称为拟单相法)和气液两相稳定点产能评价方法(以下简称为气液两相法);采用塔里木盆地牙哈气田的基础参数,应用新建立的产能评价方法计算气井在生产气油比相同、地层压力在露点压力以上及以下时的无阻流量;针对牙哈、塔中Ⅰ号、千米桥潜山、迪那2等4个凝析气田,应用新建立的产能评价方法计算凝析气井在不同生产气油比情形下的无阻流量,并选取典型井进行对比分析。结果表明:(1)采用新建立的产能评价方法可以避免因地层中油气两相流的产生导致经典产能评价方法无法计算凝析气井无阻流量的情况;(2)当地层压力高于露点压力时,地层流体以单相流体为主,可以采用拟单相法;(3)当地层压力低于露点压力,地层中出现油气两相流动时,应采用气液两相法;(4)随着生产气油比增大,采用拟单相法和气液两相法计算的无阻流量的差异逐渐减小;(5)对于凝析油含量较高、生产气油比较低的凝析气井而言,采用气液两相法计算的无阻流量更加可靠。Gas well deliverability evaluation and analysis can be difficult to carry out due to the frequent abnormalities of deliverability test data of gas condensate wells caused by seepage of oil and gas phases in the reservoirs. To this end, based upon the pseudo-single-phase seepage equation and the oil-gas two-phase seepage equation, a new deliverability evaluation method was established respectively for the following two cases when the flow of a gas well reaches the quasi-steady stage, i.e., the pseudo-single-phase stable point deliverability evaluation for the case when the formation pressure is above the dew pressure; the gas-liquid two-phase stable point deliv- erability evaluation for the case when the formation pressure is below the dew pressure. Using this established deliverability evaluation method, based on the basic parameters of the Yaha gas field, Tarim Basin, the IPR curves were first obtained of gas wells at the same production gas-oil ratio and at the formation pressure above and below the dew point pressure; then, according to the four condensate gas fields, such as Yaha, Tazhong I, Qianmiqiao and Dina 2, the absolute open flow （AOF） potentials of condensate gas wells under different gas-oil production ratios were calculated. Finally, through statistical analysis of the calculation results from typical wells, the following findings were obtained. This new deliverability evaluation method under the two states of condensate gas wells with quasi-single-phase and gas-liquid two-phase stable points can be used to avoid such cases due to the oil-gas flow in a condensate gas well unresolved by the classical deliverability evaluation methods. Also, with the increase of gas-oil ratios in gas condensate wells, a variable discrepancy is gradually reduced in AOF potentials calculated respectively by the quasi-single-phase and gas-liquid two-phase stable point deliverability evaluation equations. For the condensate gas wells with high condensate content and low condensate gas production rates, the AOF potenti

关 键 词：凝析气藏 气井 气液两相渗流 二项式产能方程 拟单相 气液两相 稳定点 产能评价方法 无阻流量 

分 类 号：TE328[石油与天然气工程—油气田开发工程]