蒸汽辅助重力泄油超覆机理研究

Steam Assisted Gravity Drainage Steam Overlap Mechanism Research

如何控制蒸汽腔变化,充分利用蒸汽超覆作用扩大蒸汽波及区域,极大程度地发挥重力对热流体的泄流作用,是蒸汽辅助重力泄油蒸汽超覆机理研究的技术关键。结合中深层巨厚砂岩稠油油藏特点,及直平组合立体开发井组结构,推广应用蒸汽超覆理论,简化蒸汽超覆系数。根据考虑重力超覆的稠油热采两区模型,建立了考虑蒸汽超覆的地层热效率计算模型,分析蒸汽超覆对地层热效率的影响。运用数值绘图软件,直观展示液相等压面及蒸汽相前缘变化趋势,合理解释蒸汽前缘滞后现象。通过分析注采参数、油藏参数、井网结构参数等对液相等压面、蒸汽相前缘变化的影响规律,探索如何利用蒸汽超覆及控制蒸汽腔变化的方法,为蒸汽辅助重力泄油的高效开发提供理论依据。

It＇ s the key technology for the mechanism research of the steam overlay phenomenon appears in steam-assisted gravity drainage process to study how to control changes of steam chamber and make full use of the steam overlay to expand the scope of steam and play gravity＇s role to the drainage of thermal fluid drastically. Considering the feature of mid-deep massive thick sandstone heavy oil reservoir and tridimensional development models with vertical and horizontal wells,using and promoting steam overlap theory,simplifying steam overlap coefficient,building the formation model for calculating the thermal efficiency which considered the influence of team overlap based on two-region model of heavy oil thermal recovery,analyzing steam overlap＇s influence to thermal efficiency of strata,the variation tendency of liquid phase isobaric and vapor phase frontier can be visually displayed with the use of numerical drawing software,explain the hysteresis phenomenon of vapor phase. Through analyzing injectionproduction parameter,oil reservoir parameter and structural parameters of well pattern＇s influence to the changes of liquid phase isobaric and vapor phase frontier,exploring the method that how to use steam overlap to control the changes of steam chamber,providing theoretical basis for the high-efficient development of steam-assisted gravity drainage process.