川南地区深层页岩气井筒清洁技术研究与现场试验  

Research and Field Test of Deep Shale Gas Wellbore Cleaning Technology in South Sichuan

作　　者：帅春岗 吴昊 王俐佳 秦梦 宋颐 徐波 SHUAI Chungang;WU Hao;WANG Lijia;QIN Meng;SONG Yi;XU Bo(Sichuan Shale Gas Exploration and Development Co.,Ltd.,Chengdu,Sichuan 610000,China;Institute of Engineering Technology,Southwest Oil&Gas Field Company,PetroChina,Chengdu,Sichuan 610000,China)

机构地区：[1]四川页岩气勘探开发有限责任公司,四川成都610000 [2]中国石油西南油气田分公司工程技术研究院,四川成都610000

出　　处：《石油工业技术监督》2025年第4期46-50,共5页Technology Supervision in Petroleum Industry

摘　　要：四川南部地区的页岩气井具有井深(平均超4 000 m)、水平段长(平均超1 500 m)的特点,因页岩气井采用大规模分段加砂压裂获取产能,大量桥塞残留碎屑、压裂砂返吐堆积于水平段产层造成生产通道受限,严重影响产能发挥以及后续维护作业,因此投产前采用连续油管进行水平段专项井筒清洁作业。长水平段井筒清洁作业面临两个难题:(1)冲砂过程中悬浮于环空的沉砂再次沉降、堆积;(2)沉积于水平段的复合桥塞钻屑、可溶桥塞的未溶解物、前期作业残留铁片打捞困难,常规打捞工具效果差。针对难题一,发明了适用于提高可改变射流方向的换向冲砂工具,有效解决了长水平段冲砂面临的再次沉降难题;针对难题二,设计、加工了通过文丘里效应产生大吸力的负压清洁工具,适用于长水平段沉积碎屑打捞,其工具端局部循环即可产生吸力的特点也适用于低压井况下捞砂作业;在新工具的基础上进行配套工艺研究,形成了适用于深层页岩气的井筒清洁技术。在深层页岩气井开展了换向冲砂工具、负压清洁工具现场试验,获得良好的效果。Shale gas wells in southern Sichuan are characterized by deep wells(over 4000 m on average)and long horizontal sections(over 1500 m on average).Because the shale gas well uses large-scale staged sand fracturing to obtain production capacity,a large number of bridge plug residual debris and fracturing sand backflow are accumulated in the horizontal production layer,causing limit-ed production channels,seriously affecting the production capacity and subsequent maintenance operations.Therefore,coiled tubing is used to carry out special horizontal wellbore cleaning operations before production.There are two problems in the cleaning opera-tion of long horizontal section wellbore:①the sand suspended in the annulus settles and piles up again during the sand washing pro-cess;②It is difficult to salvage the drilling cuttings of the composite plug deposited in the horizontal section,the undissolved matter of the soluble plug,and the residual iron sheet of the previous operation,and the effect of conventional fishing tools is poor.In view of the first problem,a reversing sand washing tool which can improve the direction of the jet and change the direction of the jet has been invented to effectively solve the problem of resettling in the long horizontal section sand washing.For the second problem,a negative pressure cleaning tool with large suction generated by Venturi effect has been designed and fabricated,which is suitable for the dredging of sedimentary debris in long horizontal section.The feature that suction can be generated by local circulation at the tool end is also suitable for sand fishing in low pressure wells.On the basis of the new tool,the supporting technology was studied,and the cleaning technology for deep shale gas wellbore was formed.Field tests of reversing sand washing tools and negative pressure cleaning tools were carried out in deep shale gas wells,and good results have been obtained.

关 键 词：页岩气井筒清洁 水平井冲砂 水平井碎屑打捞 负压清洁工具 

分 类 号：TE3[石油与天然气工程—油气田开发工程]