厚层稠油油藏直平组合火驱机理研究与试验

针对厚层稠油油藏常规直井火驱火线超覆严重、纵向动用程度差、采出程度低等问题,采用数值模拟方法,明确直平组合火驱中火线波及规律,分析直井、水平井在不同阶段的生产特征,明确直井、水平井作用机理。研究结果表明:采用直平组合火驱的井网模式改变了原有直井的火驱流场,起到向下牵引火线作用,提高了纵向波及体积;采用直平组合式井网进行火驱开发,具有驱替与泄油双重机理,能够有效扩大火驱波及体积,提高火驱采出程度。该研究为厚层稠油油藏蒸汽吞吐后转换开发方式提供了理论借鉴。

Study and Test on the Mechanism of In-situ Combustion with Combination of Vertical and Horizontal Wells in Thick Heavy Oil Reservoirs

In order to solve the problems of serious overlap in combustion range,poor longitudinal development degree and low recovery percent of in-situ combustion in conventional straight wells in thick heavy oil reservoirs,numerical simulation method was applied to determine the combustion spreading law of in-situ combustion with combination of vertical and horizontal wells,analyze the production characteristics of vertical and horizontal wells at different stages,and figure out the action mechanism of straight and horizontal wells.The results of the study showed that the well network pattern of in-situ combustion with combination of vertical and horizontal wells changed the original in-situ combustion field of vertical wells,guided the combustion downward,and improved the longitudinal swept volume;the application of in-situ combustion with combination of vertical and horizontal wells to in the reservoir development could realize the dual effects of displacement and pol drainage,effective expansion of the swept volume of the in-situ combustion,and higher recovery percent of the in-situ combustion.This study provides a theoretical reference for the development mode transition for thick heavy oil reservoirs after steam stimulation.