摘要
针对目前钻井用柔性封堵剂抗温性弱的问题,开展了抗高温聚合物纳米微球封堵剂的研究。以丙烯酰胺(AM)、对苯乙烯磺酸钠(SSS)、丙烯酸钠(AAS)、丙烯酸十三氟辛酯(TEAC)和1,3,5-三(甲基丙烯酰胺基甲酸酯)苯(B-TMAC)为原料,偶氮异丁氰基甲酰胺(CABN)为引发剂,十二烷基硫醇(TDDM)为分子量调节剂,通过自由基胶束聚合法合成了聚合物纳米微球OPTB。通过正交实验确定了最佳合成条件:反应温度105℃、反应时间20 h、反应单体浓度7.5%、CABN浓度0.4%和TDDM浓度1.5%。借助核磁共振光谱仪(1 H-NMR)进行了分子结构表征。OPTB的钻井液性能测试结果显示,OPTB对钻井液的流变性能影响较小,滤失造壁性能显著。高温老化后,OPTB的粒径仍呈单分散状态。OPTB的加量达到3.0%时,对纳微米孔隙的封堵率高达90.84%,且可有效减慢井筒内液柱压力向地层传递的速度。采用扫描电镜(ESEM)观测了160℃老化16 h前后的OPTB的微观形貌,结果显示OPTB颗粒呈球形,粒径较均一,高温作用仍有部分颗粒仍保持单分散状态。
A nano micro-spherical polymer plugging agent OPTB was developed to try to replace the flexible plugging agents presently in use,which have the shortage of low thermal stability.OTPB is a high temperature plugging agent and is synthesized through free radical micellar polymerization with several raw materials such as acrylamide(AM),sodium p-styrene sulfonate(SSS),sodium acrylate(AAS),1H,1H,2H,2H-perfluorooctyl acrylate(TEAC)and 1,3,5-tris(methacrylamido)benzene(B-TMAC).The polymerization used 1-((cyano-1-methylethyl)azo)formamide as the initiator,and dodecyl mercaptan(TDDM)as the molecular weight regulator.The optimum synthesis conditions were determined through orthogonal experiment,as follows:reaction temperature=105℃,reaction time=20 h,concentration of the monomeric raw materials=7.5%,concentration of CABN=0.4%,and concentration of TDDM=1.5%.The molecular structure of OPTB was characterized with 1 H-NMR.Experiment on the properties of the drilling fluid treated with OPTB showed that OPTB has little effect on the rheology of the drilling fluid,and the quality of the mud cake was significantly improved.After aging at high temperature,the particle size of OPTB is still in a monodisperse state.At a concentration of 3.0%,90.84%of the nanometer-sized and micron-sized pores can be plugged by OPTB,and this plugging effect can effectively slow down the transmission of the pressure of the fluid column in the wellbore into the formations.The micromorphology of OPTB before and after aging at 160℃for 16 h observed under SEM showed that the particles of OPTB are spherical with narrow size distribution.At elevated temperatures,part of the OPTB particles is still in monodisperse state.
作者
黄乘升
褚奇
李涛
刘金华
HUANG Chengsheng;CHU Qi;LI Tao;LIU Jinhua(Liupu Drilling Branch,SINOPEC East-China Petroleum Engineering Co.,Ltd.,Zhenjiang,Jiangsu 212000;State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development,Beijing 100101;Sinopec Research Institute of Petroleum Engineering,SINOPEC,Beijing 100101)
出处
《钻井液与完井液》
CAS
北大核心
2022年第2期139-145,共7页
Drilling Fluid & Completion Fluid
基金
国家自然科学基金重大项目“页岩油气高效开发基础理论研究”(51490650)。
关键词
钻井液
井壁稳定
聚合物纳米微球
抗高温
封堵性能
Drilling fluid
Borehole wall stability
Nano polymer microsphere
High temperature resistant
Plugging performance
