摘要
针对水平井段间非均质性较强或钻遇断层、较大天然裂缝带的情况,四川盆地页岩气井套变现象时有发生,导致常规机械分段工具无法通过套变段,对页岩气水平井高效分段改造带来巨大挑战。为此,提出了一种适用于非常规油气藏水平井的非顺序压裂工艺,该工艺不同于传统的从水平段B靶点向A靶点的顺序压裂,而是在水平分段改造井段的任意位置实现分簇射孔与压裂,且每次压裂后全井段可实现暂时封堵。对于可能发生风险的井段可先行避开,先压裂正常井段,再压裂风险井段,对于水平段受断层影响的情况或套变井提供极具针对性的解决措施。以川南页岩气A1井为例开展现场试验,验证了水平井非顺序压裂工艺的可行性,并在一定程度上减弱较大裂缝带对压裂改造体积的负面影响,有效规避压裂改造区域的重复覆盖。此外,该工艺使用的工具串外径最小仅79 mm,对套变井段也具有适应性和针对性,可作为桥塞分段工艺的有益补充,具有广阔的推广应用价值。
Due to strong heterogeneity between horizontal well sections or encounter faults,large natural fracture zones during drilling,casing deformation of shale gas wells in Sichuan Basin often occurs,which will result in conventional mechanical segmentation tools cannot pass through the casing deformation section,posing a huge challenge to the efficient stimulation of shale gas horizontal wells.To this end,a non-sequential fracturing process suitable for unconventional oil and gas reservoir horizontal wells is proposed.This process is different from the traditional sequential fracturing from target B in the horizontal section to target A,but instead achieves cluster perforation and fracturing at any position of the horizontal segmented reconstruction well section,and the entire well section can be temporarily sealed after each fracturing.For well sections that may be at risk,it is recommended to avoid them and fracturing the normal well section first,and then fracturing the risky well section.For horizontal sections affected by faults or casing wells,highly targeted solutions are provided.Taking the A1 well of shale gas in southern Sichuan as an example,on-site experiments verified the feasibility of non-sequential fracturing technology for horizontal wells,and to some extent,the negative impact of large fracture zones on the volume of stimulation was reduced,effectively avoiding repeated coverage of the stimulation area.In addition,the minimum outer diameter of the tool string used in this process is only 79 mm,which is also adaptable and targeted for the casing transformation well section.It can be a beneficial supplement to the plug segmentation process and has broad promotion and application value.
作者
朱炬辉
ZHU Juhui(Downhole Operation Company of CNPC Chuanqing Drilling Engineering Co.,Ltd.,Chengdu,Sichuan 610051,China)
出处
《钻采工艺》
CAS
北大核心
2023年第4期51-56,共6页
Drilling & Production Technology
基金
国家自然科学基金区域创新发展联合基金“四川深层页岩气水平井缝网压裂填砂暂堵物理机制研究”(编号:U19A2043)
中国石油川庆钻探工程有限公司科研课题“提升3500~4500 m页岩储集层水力裂缝复杂程度和有效性工艺技术研究”(编号:CQ2021B-39-Z2-4)。
关键词
页岩气
非常规储层
水平井
非顺序压裂
压裂评估
分簇
桥塞
shale gas
unconventional reservoir
horizontal well
non-sequential fracturing
fracturing evaluation
clustering
plug
作者简介
朱炬辉(1978-),博士后,高级工程师,2007年毕业于西南石油大学,主要从事油气藏增产改造技术研究与管理工作。地址:(610051)四川省成都市成华区华盛路46号川庆钻探工程有限公司井下作业公司,电话:13982163685,E-mail:zhujh_jx@cnpc.com.cn
