火驱储层区带特征实验研究

利用一维和三维火烧油层驱油物理模拟实验装置,研究了稠油油藏直井井网火驱过程中各个地层区带的宏观热力学特征以及压力场、温度场、饱和度场分布规律。研究表明,从注气井到生产井可依次将地层划分为已燃区、火墙(燃烧带)、结焦带、油墙、剩余油区5个具有明显热力学特征的区带。结焦带为火驱过程提供固态燃料,高含油饱和度油墙是地层中压力梯度最大的区带,是注气压力的集中消耗带。保持一个稳定的油墙是确保火驱前沿持续推进、实现稳产和提高采收率的必要条件。

Experimental research on thermodynamic characteristics of in-situ combustion zones in heavy oil reservoir

The pressure, temperature and oil saturation distributions and general thermodynamic characteristics of in-situ combustion zones with vertical well pattern in heavy oil reservoir were experimentally investigated by using 1D and 3D physical modeling systems. The experimental results indicated that five zones were characterized with distinctive thermodynamics from air injecting well to producing well, including burned zone, combustion zone, coking zone, oil bank and residual oil zone. The coking zone supplies the solid fuel for burning, while the high oil saturation bank with the largest pressure gradient in the formation is the main consumption zone of gas-injecting pressure. Maintaining a stable oil bank is necessary to ensure the forward movement of fire front, and fufill stable production and enhanced oil recovery.