不同驱动类型气藏的采出特征

PRODUCTION FEATURES OF THE GAS RESERVOIRS WITH VARIOUS DRIVE TYPES

为了更为准确地判定气藏的驱动类型，文章采用导数的方法，从研究气藏的物质平衡方程式入手，通过对气藏含水饱和度随地层压力变化的关系式的推导，获得了水驱气藏两种不同驱动作用下的基本方程式的微分形式及其导数的结果。因而得到了不同类型气藏的采气速度与其相应的地层压力降落的关系式，以及由此作出的不同的压力变化特征曲线，直观地表达了不同驱动类型气藏的采出特征。为气藏早期ｐ／ｚ—Ｇｐ关系曲线为近似直线而不易判定其驱动类型提供了解决问题的办法，同时证明了气驱气藏只是水驱气藏在含水饱和度为零时的一个特例，并提出了在自然力驱动中，刚性水压驱动气藏并不存在的观点。文章还为研究和制定气域合理的采气速度提供了方法和思路。

In order to accurately discriminate the drive typeS of gas reservoirs, started from studying the material balance equations by derivative method, the differential form and derivative result of the basic equations of water drive gas reservoir in the conditions of two different drive actions are obtained through deriving the relational expression that water saturation of gas reservoir changes with stratum pressure. So the relational expression that the gas production velocity of various gas reservoir reduces with the stratum pressure and the feature curve of changes are oh tamed. The production features of various gas reservoirs can be visually expressed.A method is of discriminating drive types of gas reservoirs, as all of the P/Z-Gp relational curves in the early period of gas reservoirs are approxiamate straight lines makes it difficilt,is provided. It is proved that gss drive rbervoir is only a special example of water drive reservoirs when the water saturation of water drive reservoirs is zero. The viewPOint that rigid water drive gas reservoir does not exist while driving by natural force is proposed out. The measure and thinking for studing and formulating the reasonable production velocity of 88s reservoir are also provided.