弹性二相法新式的推导及应用

doi:10.13809/j.cnki.cn32-1825/te.2023.02.001

摘要/Abstract

摘要：

对于定容封闭气藏，当气井以稳定产量开井生产后，根据井底流动压力与时间的变化动态，可划分为非稳定阶段、过渡阶段和拟稳定阶段。其中的非稳定阶段称为弹性一相阶段，拟稳定阶段称为弹性二相阶段。后者是评价气井控制原始地质储量（OGIP）的重要方法。陈元千于1991年提出的拟稳定阶段的弹性二相法，在中国得到了广泛的重视和应用，被连续多次列于中华人民共和国石油天然气行业标准。基于在有限封闭边界气藏内，一口以稳定产量生产的气井，考虑天然气、岩石和束缚水的弱弹性膨胀作用的扩散方程，经推导得到了由井底流动压力与累积产量表示的拟稳定阶段弹性二相法的新式。该式可用于评价气井控制的原始地质储量（OGIP），它优越于由井底流动压力与时间关系表示的原式，克服了因产量波动对评价结果造成的影响。通过实测应用表明，弹性二相法的新式是实用有效的。

关键词: 定容封闭气藏, 拟稳定阶段, 弹性二相法, 原始地质储量, 新式, 推导, 应用

Abstract:

For volumetric closed gas reservoirs, when the gas well produces with stable production rate, it can be divided into unsteady state stage, transient stage and pseudo steady state stage according to the variation behaviours of flowing bottom hole pressure and producing time. The unsteady state stage is called the elastic one-phase stage, and the pseudo steady state stage is called the elastic two-phase stage. The latter is a dynamic method to evaluate the Original Gas in Place（OGIP） controlled by gas wells. The elastic two-phase method proposed by CHEN Yuanqian in 1991 in the pseudo steady state stage has been repeatedly listed in the National Oil and Gas Industry Standards, and has been widely valued and applied in China. Based on the diffusion equation considering the elastic expansions of natural gas, rock and irreducible water in a gas well with stable production in the finite closed gas reservoir boundary, a new elastic two-phase method for the pseudo steady state stage represented by flowing bottom hole pressure and cumulative production rate is derived, which can be used to evaluate the original gas in place（OGIP）controlled by a gas well. The new formula of elastic two-phase method is superior to the old formula which based on the relationship between flowing bottom hole pressure and production time, and the new can overcome the influence of production fluctuation on the evaluation results. The application shows that the new formula of elastic two-phase method is practical and effective.

Key words: volumetric closed gas reservoir, pseudo steady state stage, elastic two-phase method, original gas in place, new formula, derivation, application

中图分类号:

陈元千,石晓敏. 弹性二相法新式的推导及应用[J]. 油气藏评价与开发, 2023, 13(2): 135-140.

CHEN Yuanqian,SHI Xiaomin. Derivation and application of a new formula of the elastic two-phase method[J]. Reservoir Evaluation and Development, 2023, 13(2): 135-140.

图/表 4

图1

表1

苏5井压降曲线测试的数据表[7,9]"

t（d）	G_p（10⁴m³）	p_wf（MPa）	$p w f 2$ （MPa²）
0.045	0.446	26.722	714.049
0.111	1.113	26.007	676.385
0.139	1.388	25.913	671.489
0.183	1.833	25.819	666.605
0.228	2.279	25.703	660.649
0.283	2.833	25.602	655.483
0.345	3.446	25.561	653.380
0.395	3.946	25.495	649.975
0.505	5.054	25.373	643.804
0.639	6.388	25.335	641.847
0.833	8.333	25.233	636.704
1.100	11.000	25.148	632.397
1.522	15.221	24.977	623.846
1.800	18.000	24.913	620.643
2.278	22.779	24.705	610.332
2.889	28.888	24.511	600.789
3.916	39.158	24.187	584.992
5.229	52.288	23.816	567.188
6.790	67.896	23.452	550.010
8.345	83.454	23.166	536.668
10.873	108.729	22.538	507.979
13.998	139.979	21.921	480.530
16.623	166.229	21.481	461.453
19.304	193.038	21.013	441.534
22.165	221.646	20.528	421.411
24.568	245.675	20.093	403.717
28.206	282.063	19.504	380.390
30.037	300.371	19.212	369.097

表1

图2

图3

参考文献 9

[1]	陈元千: 油气藏工程计算方法(续篇), 石油工业出版社, 北京, 1991, 37-47.
	Chen Yuanqian: Petroleum reservoir engineering calculation methods(Continuation), Petroleum Industry Press, Beijing, 1991, 37-47.
[2]	陈元千: 现代油藏工程(第2版), 石油工业出版社, 北京, 2020, 254-259,303-304.
	Chen Yuanqian: Modern petroleum reservoir engineering (Second Edition), Petroleum Industry Press, Beijing, 2020, 254-259, 303-304.
[3]	Dake L.P.: Fundamentals of reservoir engineering, Elsevier Scientific Publishing Company, Amsterdam-Oxford-New York, 1978, 141-145.
[4]	Craft B.C. and Hawkins M.F.: Applied petroleum reservoir engineering, Prentice-Hall, Inc., Englewood Cliffs, N.J., 1959,309-314.
[5]	陈元千: 油气藏工程实践, 石油工业出版社, 北京, 2005, 167-175, 260-269.
	Chen Yuanqian: The practice of petroleum engineering, Petroleum Industry Press, Beijing, 2005, 167-175, 260-269.
[6]	陈元千: 油气藏工程实用方法, 石油工业出版社, 北京, 1999, 263-277.
	Chen Yuanqian: Practical methods of petroleum reservoir engineering, Petroleum Industry Press, Beijing, 1999, 263-277.
[7]	彭仕宓, 陈元千: 实用油气田开发地质与油藏工程方法, 石油工业出版社, 北京, 2013, 276-282, 398-405.
	Peng Shimi, Chen Yuanqian: Practical petroleum development geology and reservoir engineering method, Petroleum Industry Press, Beijing, 2013, 276-282, 398-405.
[8]	陈元千: 油气藏工程论文集(2013—2018), 石油工业出版社, 北京, 2019, 261-268.
	Chen Yuanqian: Article collection of petroleum Reservoir engineering(2013—2018), Petroleum Industry Press, Beijing, 2019, 261-268.
[9]	陈元千: 评价气藏原始地质储量和原始可采储量的动态法——为修订《SY/T 6098—2010》标准而作, 天然气勘探与开发, 2021, 44(1)1-12.
	Chen Yuanqian:Dynamic methods for estimating initial gas in-place and initial recoverable reserves in gas reservoirs: For the revised《SY/T 6098—2010》, Natural Gas Exploration and Development, 2021, 44(1)1-12.