摘要
我国煤层气资源储量丰富,但是单井产量低、增产难度大、稳产期短是煤层气高效开发的瓶颈难题。此外,煤层气井在排采过程中普遍存在着由于出砂、出煤粉导致关停井的现象,严重制约了煤层气的开发效果。为了实现定点、定向、体积造缝,研发了水力喷射定向多段多簇压裂配套防砂工艺。该方法通过采用“反重力法”在水平井段实现喷砂射孔喷嘴的精准定向,集喷砂射孔、水力封隔、体积压裂为一体,提高产量的同时有效防砂。以山西沁水盆地郑庄区块3号煤层为改造对象,开展了2口L型水平井分段压裂工程试验,以“4点钟—8点钟”方向定向喷射造缝,取得了良好的增产和防砂双重效果。结果表明:①2口L型套管水平井均压裂10段,其中1口井含1段2簇、簇间距10 m,单段平均砂量50 m^(3)、液量800 m^(3),施工顺利,未出现压裂液大量滤失、窜层和砂堵的问题;②改造后2口井稳定日产气量分别为10100,16000 m^(3)/d,日产气量达到10000 m^(3)/d的提产时间为1个月,具有提产速度快、达产时间短、稳产气量高的特点,日产气量是同区块直井单井日均产气量的5~9倍,是水平井单井日均产气量的1.4~2.3倍;③现场取水样表明水质较清,2口井均未出砂,排采设备运行平稳。除了原生结构煤储层改造外,该技术还可推广应用于构造煤顶底板定向压裂、多层/薄互层定点定向穿层改造等,为煤层气水平井的高效开发提供了新的技术支撑和增产方向。
Coalbed methane resources is abundant in China.But low single well daily production,difficult stimulation and short stable production time are the bottlenecks for efficient development of coalbed methane.In addition,it is common to shut down Wells due to sand production,which seriously restricts the exploitation efficiency of coalbed methane.Hydra-jet oriented multi-stage/multi-cluster fracturing technology is developed for pin-point and oriented network fracturing.The abrasive jet perforation,hydraulic isolation,network fracturing,and precise orientation are integrated into this technique.Oriented perforation and fracturing are achieved by using the“anti-gravity”method to increase production and effectively control sand.No.3 coal seam in Zhengzhuang block,Qinshui Basin,Shanxi Province is taken as the object of stimulation,2 L-shaped horizontal wells were fractured.Oriented perforation was carried out in the direction of 4 o’clock and 8 o’clock,which achieved a good dual effect of production enhancement and sand control.The results show that:①There are 10 fracturing stages in ZX-1L well and 10 fracturing stages in ZX-2L well(consists of two clusters in one stage,with a cluster spacing of 10 m).The average sand amount in each stage of the two wells is 50 m^(3)and 800 m^(3)respectively.The fracturing was successful,and there are no problems of fracturing fluid loss,interzonal cross-flow and sand plugging.②The stable daily gas production of the two wells is 10100 m^(3)/d and 16000 m^(3)/d,respectively,and the time for production increment is one month when the daily gas production reaches 10000 m^(3)/d,which has the characteristics of fast production increment speed and high stable gas production.The daily gas production is 5-9 times that of vertical wells and 1.4-2.3 times that of horizontal wells in the same block.③The water samples taken from 2 wells showed that the water quality was relatively clear,and no sand was produced.The production equipment ran smoothly.This technology can be widely applied
作者
黄中伟
李志军
李根生
杨睿月
梅永贵
牛继磊
李宗源
吴春升
温海涛
丛日超
HUANG Zhongwei;LI Zhijun;LI Gensheng;YANG Ruiyue;MEI Yonggui;NIU Jilei;LI Zongyuan;WU Chunsheng;WEN Haitao;CONG Richao(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing 102249,China;PetroChina Huabei Oilfield Company,Renqiu 062500,China;College of Petroleum Engineering,China University of Petroleum,East China,Qingdao 266580,China;Shanxi CBM Exploration&Development Branch,PetroChina Huabei Oilfield Company,Changzhi 046000,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2022年第7期2687-2697,共11页
Journal of China Coal Society
基金
国家自然科学基金国际(地区)合作与交流资助项目(52020105001)。
关键词
煤层气
增产改造
体积压裂
定向布缝
防砂
coalbed methane
reservoir stimulation
network fracturing
oriented fracturing
sand control
