薄层特,超稠油油藏高周期蒸汽吞吐阶段开发策略研究

方法结合矿场试验，应用油藏数值模拟技术，研究组合注汽、动态配汽、强排和降粘等一系列开发策略。目的提高河南油区稠油油藏高周期蒸汽吞吐效果，实现“八五”后产能接替。结果采用面积组合注汽方式，泄油范围和产油量分别提高了0．85和0．58倍，热损失率下降了10个百分点；在前4周期累积来注比分别为0．7、0．9、1．1和1．3的情况下，后续周期最佳注汽量比前一周期分别递减10％、持平、递增10％和递增20％，此时增产油汽比最高；对油层厚度较大、供液能力较强的井，采取换大泵、调大参数等强排技术；现场实践表明：化学降粘、热洗井及伴热降粘技术，使周期生产时间延长了1．1倍，周期产油量和油汽比分别比前一周期提高了0．9和1．2倍，采注比和回来水率均提高了1．4倍，平均单井累积存水下降480t。结论改善薄层特、超稠油油藏高周期吞吐效果的关键是提高系统热效率；合理组合注汽，可有效地抑制汽窜，扩大蒸汽波及体积；动态配汽和超稠油降粘技术，可最大限度地利用地层储热；对油层厚度较大、供液能力较强的油井，必须实现强排。

Research on strategy for multi-cycle development during steam soak phase in thin layer and extra, super heavy oil reservoirs.

Method Combining with field experiments, a series of development strategies such ascombination steam injection, dynamic steam allocation, enhanced drainage and viscosity reduction are studied by using reservoir numerical simulation technology. Purpose To improve multi-cycle steam soaking result of heavy oil reservoirs in Henan oil area, and toachieve productivity replacement after the eighth five-year plan period. Result By usingareal array steam injection, drainage area and oil production raised respectively 0. 85 and0. 58 times than before,the heat loss rate reduced 10%; when the cumulative injection-production ratios of the former four cycles are respectively 0. 7, 0. 9, 1. 1, and 1. 3, the optimalsteam injection rate of the following cycle should respectively lapse 10%, be equal, increase10% and 20%, thus achieving the highest stimulation oil-steam ratio; enhanced drainagetchniques such as using large pump and parameters are adopted in wells with thick oil-bearing layer and high fluid supplying ability; field practice shows that: by using chemical viscosity reduction, thermal well-flushing and viscosity reduction with heat tracing, periodic production time elongated 1. 1 times, periodic oil production and oil-steam ratio respectively improved 0. 9 and 1. 2 times than the former cycle, both production-ijection ratio and waterback production ratio increased 1. 4 times, average accumulated water sorage in single wellreduced 480 t. Conclusion To improve system heat efficiency is the key to improve multi-cycle steam soaking result in thin layer and extra,super heavy oil reservoirs 3 rational combination steam injection can prevent steam channeling and expand steam swept volume; dynamicsteam allocation and viscosity reduction for extra heavy oil can utilize formation heat to thebiggest extent ; for those wells with thick oil-bearing layer and stronger fluid supplying ability, enhanced drainage is necessary.