致密砂砾岩储层高效开采技术探讨

Discussion on High Efficient Development Technology of Dense Glutenite Reservoirs

摘要: 徐深气田深层砂砾岩开发存在两个难题：一是由于储层横向变化大，储层致密、物性差，开采过程中出现关井压力高、气井产量低、稳产能力差等现象；二是营四段砂砾岩储层直井和水平井压后增产效果不理想，存在砾块碎落堵塞缝口，压裂施工困难，储层难以得到有效改造的问题。通过攻关形成产能突破和长期稳产工艺以及经济效益高的配套技术。开展双分支水平井开发，优化钻具组合和井眼轨迹设计、壁挂式悬挂系统设计，实施完井及裸眼分段压裂工艺，化学及机械暂堵工艺，保证了分支井眼接口密封、井眼重入、分段压裂的要求，成功实现了储层有效动用，实现了气田高效开发。

Abstract: There existed 2 problems during the development of glutenite reservoirs in Xushen Gas Field: the first was the big lateral change of reservoirs with reservoir density and poor physical property. The shut-in pressure was high, and production in the gas wells and the stabilized production capacity were low. The second was that the stimulation effect in the vertical and horizontal wells was not ideal in the glutenite reservoirs of Ying 4 Section after fracturing, and there existed the problems of difficult reconstruction of reservoirs caused by fractures blocking with glutenite debris and in the fracturing operation. Through technical research and development, the technology of productivity breakthrough and long-term stable production and high efficient matching techniques were established. By using the dual branch horizontal wells and optimization of BHA and well design trajectory, wall mounted suspension system design, the technologies of completion and open hole staged fracturing, chemical and mechanical plugging process are implemented for ensuring the branch hole sealing, borehole re-entry and staged fracturing requirements. The effective producing in reservoirs and high efficient development of gas fields are achieved.