缝洞型油藏注氮气吞吐参数优化研究

Nitrogen Huff-Puff Parameter Optimization in Fracture-Cavity Reservoir

针对缝洞型油藏注气井低产低效的问题,基于AD19井的地质模型,研究周期注气量、注气速度、闷井时间、采液强度等参数对注气效果的影响,考虑地质因素的不确定性,建立不同充填类型的数值模型,形成不同充填条件下的注气参数优化图版。研究结果表明,砂泥充填的储集体,应该选择小注气量、低注气速度、低采液强度、长闷井时间的注气技术对策;垮塌充填的储集体,应该选择大注气量、高注气速度、高采液强度、短闷井时间的注气技术对策。实例研究表明,该图版的符合率达到78%,可以作为矿场注气参数选取的一种可靠依据。该研究为缝洞型油藏提质增效奠定了科学的理论基础。

Based on the geological model of Well AD19, the effects of periodic nitrogen injection volume, injection rate, soaking time, liquid production intensity and other parameters on nitrogen huff-puff performance are studied to enhance the production and efficiency. Considering the geology uncertainty, the numerical simulation models with different filling patterns are established to gain the corresponding optimization plates under different filling patterns. Research indicates that low nitrogen injection volume, low injection rate, low liquid production intensity, long soa- king time are appropriate for the reservoir filling with sand and mud. High nitrogen injection volume, high injection rate, high liquid production intensity and short soaking time are appropriate for the reservoir with collapsed filling. Case study shows a coincidence rate of 78%, which can be used as a reliable basis for the optimization of field nitrogen injection parameters. This research could provide certain scientific theoretical foundation for enhancing fracture-cavity reservoir development performance.