塔里木油田轮古井区注水替油参数优化研究

Parameter Optimization Research for Water Huff and Puff Technology in Lungu Well Area of Tarim Oilfield

塔里木油田轮古井区奥陶系碳酸盐岩油藏属于缝洞型油藏,油藏非均质性极强,很多单井由于钻遇封闭缝洞体产量迅速递减。注水替油技术可以大幅度恢复停喷或低效油井的产能,是开发缝洞型油藏的有效新方法之一。注水替油的注采参数是否合理对注水替油的开发效果至关重要。以塔里木油田轮古井区注水替油典型井的地质、流体资料为基础,建立单井注水替油的地质模型,通过数值模拟的方法优化注水时机、周期注水量、注水速度、焖井时间、开井工作制度等注采参数,并将注采参数无因次化或拟合公式,以消除注水前油井生产动态差异对优化参数造成的影响,使优化参数更具实用性。

The ordovician reservoirs in Lungu well area of Tarim Oil field belong to the fracture-cavity carbonate reservoirs, which are highly non-homogeneous. Single-well oil production declines rapidly because of reservoir energy shortage. Water huff and puff （cyclic water stimulation） is a novel method for the exploitation of the fracture-cavity carbonate reservoir, which can substantially improve single-well productivity. Whether the injection-production parameters of water huff and puff tech- nology are appropriate is essential to the oilfleld development. Based on the geological and fluid information of the typical water huff and puff well, the geological model for water huff and puff technology is built to optimize the corresponding factors which include injection timing, cyclic water injection rate, injection speed, soaking time and daily fluid production rate. In this research, the corresponding factors are dimensionless or correspond to fitting formula to eliminate the effects of production performance differences before water injection and make the optimized parameters more effective.