致密白云岩储层加砂压裂裂缝导流能力实验研究  

Experimental study of propped fracture conductivity in tight dolomite reservoir

作　　者：时贤[1,2] 葛晓鑫 张燕明[3] 黄维安[1,2] 战永平[1,2] 古永红[3] 牟春国[3] SHI Xian;GE Xiaoxin;ZHANG Yanming;HUANG Weian;ZHAN Yongping;GU Yonghong;MOU Chunguo(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao City,Shandong Province,266580,China;Key Laboratory of Unconventional Oil&Gas Development,Ministry of Education,China University of Petroleum(East China),Qingdao City,Shandong Province,266580,China;Oil&Gas Technology Research Institute,Changqing Oilfield Company,PetroChina,Xi’an City,Shaanxi Province,710021,China)

机构地区：[1]中国石油大学(华东)石油工程学院,山东青岛266580 [2]中国石油大学(华东)教育部非常规油气开发重点实验室,山东青岛266580 [3]中国石油长庆油田分公司油气工艺研究院,陕西西安710021

出　　处：《油气地质与采收率》2023年第4期167-172,共6页Petroleum Geology and Recovery Efficiency

基　　金：国家科技重大专项“大型油气田及煤层气开发”项目47“致密气富集规律与勘探开发关键技术”(2016ZX05047);国家自然科学基金项目“致密储层水平井定面射孔水力压裂裂缝起裂与扩展机理”(51704324)。

摘　　要：为了探讨加砂压裂技术在白云岩储层改造中的适应性,开展了致密白云岩储层加砂压裂裂缝导流能力实验,分析不同因素对加砂压裂裂缝导流能力的影响。实验结果表明,影响白云岩储层加砂压裂裂缝导流能力因素依次为支撑剂粒径、铺砂浓度、加砂模式、铺砂方式、支撑剂强度。对比单一支撑剂类型,混合支撑剂铺设时可以获得较好的导流能力,且粒径越大支撑剂占比越高,导流能力表现则越好。脉冲加砂模式下的裂缝导流能力变化波动较大,但是同样可以满足白云岩储层改造的裂缝导流能力。结合压裂施工效果和经济成本,优选支撑剂强度为69 MPa,平均铺砂浓度为1.8 kg/m^(2)的加砂参数即可满足白云岩储层现场加砂压裂的需要。白云岩储层由于杨氏模量高、闭合应力大,所以缝宽较小,而通过实施脉冲加砂模式则可以一定程度降低加砂压裂过程中的砂堵风险。Experiments on the conductivity of propped fracture in tight dolomite reservoirs were conducted to analyze the effects of different factors on the conductivity of propped fractures and thus explore the adaptability of proppant fracturing technology to dolomite reservoir stimulation.The experimental results showed that the factors affecting the conductivity of propped fractures in dolomite reservoirs are as follows:the particle sizes of proppants,proppant concentrations,proppant injection modes,proppant laying methods,and proppant strength.Compared with a single proppant,the mixed proppant can obtain better conductivity,and a larger particle size is accompanied by a higher proportion of proppants and better conductivity.In addition,the conductivity of fractures registers significant fluctuations under the pulsed proppant injection mode,but it can satisfy the stimulation requirement of dolomite reservoirs.Considering the fracturing effect and cost,the on-site sand fracturing needs in the dolomite reservoir can be met with the proppant strength of 69 MPa and an average proppant concentration of 1.8 kg/m^(2).The dolomite reservoir has a small fracture width because of the large Young’s modulus and high closure stress.Hence,the risk of proppant plugs in proppant fracturing can be reduced to a certain extent by the pulsed proppant injection mode.

关 键 词：白云岩 加砂压裂 裂缝导流能力 支撑剂 闭合应力 

分 类 号：TE344[石油与天然气工程—油气田开发工程]