碎软低渗煤层水平井水力喷砂射孔工艺优化  

Optimization of hydraulic jet perforation tools for horizontal wells in broken soft and low permeability coal seams

作　　者：张永成 赵祉友 汪奇 文贤利 刘亮亮 李德慧 张为 王旭超 李大冬 ZHANG Yongcheng;ZHAO Zhiyou;WANG Qi;WEN Xianli;LIU Liangliang;LI Dehui;ZHANG Wei;WANG Xuchao;LI Dadong(State Key Laboratory of Coal and CBM Co-mining,Jincheng 048000,China;Jinneng Holding Group Co.,Ltd.,Datong 037000,China;Underground Service Company of Zhongyuan Petroleum Exploration Bureau,Puyang 457000,China;Engineering Technology Research Institute of Xinjiang Oilfield Company,Karamay 834000,China;China Petrolum Engineering and Construction Corporation,Beijing 100120,China;Huayang No.1 Coal Mine,Yangquan 045000,China)

机构地区：[1]煤与煤层气共采国家重点实验室,山西晋城048000 [2]晋能控股集团有限公司,山西大同037000 [3]中原石油勘探局井下特种作业公司,河南濮阳457000 [4]新疆油田公司工程技术研究院,新疆克拉玛依834000 [5]中国石油工程建设有限公司,北京100120 [6]华阳一矿通风工区,山西阳泉045000

出　　处：《煤炭工程》2024年第2期17-23,共7页Coal Engineering

基　　金：山西省煤层气联合研究基金项目(2016012003);中国工程院院地合作项目(2020SX4);山西省揭榜招标项目(20201101004)。

摘　　要：针对碎软低渗煤层水平井煤粉产出危害,提出采用水力喷砂射孔压裂来实现“射孔-增透-控粉”为一体的压裂改造理念,具体工艺包含水力喷砂射孔、高压射流、环空压裂以及水力补射孔清洗。通过成本及工艺对比,选择油管拖动水力喷砂射孔方式进行压裂,并对工艺和关键工具进行优化。首先,优化防反冲蚀破坏一体化硬质合金圆锥收敛型喷嘴,能实现排量2.0~2.5 m3/min时,射流压力为16.5~25.8 MPa。其次,优化喷射器本体,能有效射穿套管、水泥塞,并射入岩石一定深度。配套一体化管柱顺利完成了煤层气U型水平井压裂和补射孔施工各8段,每段射孔时间15 min以上,并充分顶替返排煤粉,投产3年后产气量仍达到3500 m3/d以上,表明优化工艺达到了碎软低渗煤层改造效果。与连续油管分段压裂技术相比,油管拖动水力喷射压裂单段压裂作业成本降低了28.5%。Aiming at the harm of pulverized coal production in horizontal wells in broken soft and low permeability coal seams,a new concept of hydraulic jet perforation and fracturing was proposed,to enhance coal seam permeability and reduce pulverized coal.The process was comprised hydraulic jet perforation,high-pressure jet,annulus fracturing and hydraulic jet perforation cleaning.Through the comparison of cost and process,drag tubing hydraulic sand blasting perforation fracturing was selected,and the process and key tools were optimized.Firstly,the integrated cemented carbide conical convergent nozzle was optimized to prevent reverse erosion damage,to maintain a jet pressure of 16.5~25.8 MPa when the displacement was 2.0~2.5 m3/min.Secondly,the ejector body was optimized,to effectively shoot through the casing and cement plug,and shoot into the rock to a certain depth.The supporting integrated string successfully completed the construction of 8-stage fracturing and 8-stage supplementary perforation of coalbed methane U-shaped horizontal well.The perforation time of each section was more than 15 min,and fully displaced the backflow pulverized coal.After three years of operation,the gas production is still more than 3500 m3/d,which shows that the optimized process has achieved the transformation effect of broken soft and low permeability coal seams.Compared with coiled tubing staged fracturing technology,the single-stage fracturing operation cost through hydraulic jet fracturing by dragging tubing has been reduced by 28.5%.

关 键 词：碎软低渗煤层 水平井 水力喷砂射孔 压裂 

分 类 号：TD712[矿业工程—矿井通风与安全]