摘要
针对常规改性淀粉降滤失剂高温易降解导致钻开液抗温性差的问题,采用接枝共聚法,以天然淀粉为原料、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)与丙烯酰胺(AM)为接枝单体制备了一种抗温增黏降滤失剂STAR-AM,通过红外光谱表征了产物结构。将STAR-AM与流型调节剂、封堵剂、屏蔽暂堵剂、润滑消泡剂、HCOONa等复配制得无黏土相抗高温钻开液体系。分别评价了STAR-AM在基浆和钻开液体系中的抗温、增黏和降滤失性能,考察了钻开液的储层保护效果。结果表明,在淀粉(玉米淀粉、木薯淀粉质量比为60∶40)、单体(AMPS、AM物质的量比为1∶2)质量比为65∶35的条件下制备的STAR-AM具有较好的抗温增黏降滤失作用。STAR-AM加量为10~25 g/L时,基浆150℃老化后的黏切显著提高,API滤失量大幅降低;加入甲酸盐后,基浆抗温能力从150℃提高至170℃。STAR-AM加量为25 g/L时,无黏土相抗高温钻开液170℃老化后的API滤失量仅1.3 mL,HTHP滤失量仅10.2 mL,明显优于常规改性淀粉类降滤失剂;且具有优异的储层保护效果,岩心渗透率恢复值超过95%,可在超深水平井裸眼钻完井中推广应用。
Aiming at the problem of poor temperature resistance of drilling fluid due to the high temperature degradation of conventional modified starch filtration reducers,a filtration reducer STAR-AM with temperature resistance and viscosity increase was prepared by using natural starch as raw material,2-acrylamido-2-methylpropanesulfonic acid(AMPS)and acrylamide(AM)as grafting monomer through graft copolymerization method.The structure of the product was characterized by infrared spectroscopy.STAR-AM was compounded with flow modifier,plugging agent,shielding temporary plugging agent,lubricating defoamer and HCOONa to form a clay-free drilling fluid system with high temperature resistance.The temperature resistance,viscosity increase and fluid loss reduction performances of STAR-AM in base mud or drilling fluid system were evaluated respectively,and the reservoir protection effect of the drilling fluid was investigated.The results showed that STAR-AM prepared under the condition of starch(corn starch and tapioca starch in mass ratio 60∶40)and monomers(AMPS and AM in molar ratio 1∶2)in mass ratio 65∶35 had good performance of temperature resistance,viscosity increase and filtration reduction.When the dosage of STAR-AM was 10-25 g/L,the viscosity and shearing force of base mud significantly increased after aging at 150℃,and the API filtration greatly reduced.After adding formate,the temperature resistance of base mud increased from 150℃to 170℃.When the dosage of STAR-AM was 25 g/L,the API filtration of the clay-free drilling fluid after aging at 170℃was only 1.3 mL,and the HTHP filtration was only 10.2 mL,which was significantly better than that of conventional modified starch filtration reducers.It had excellent protection effect on reservoir,and the permeability recovery of core exceeded 95%,which could be popularized and applied in the open-hole drilling and completion of ultra-deep horizontal well.
作者
潘丽娟
吴宇
翟科军
龙武
由福昌
PAN Lijuan;WU Yu;ZHAI Kejun;LONG Wu;YOU Fuchang(Research Institute of Petroleum Engineering,Northwest Oilfield Branch Company,Sinopec,Urumqi,Xinjiang 830011,P R of China;Key Laboratory for Enhanced Oil Recovery in Fractured and Vuggy Reservoirs,Sinopec,Urumqi,Xinjiang 830011,P R of China;Hubei Cooperative Innovation Center of Unconventional Oil and Gas,Yangtze University,Wuhan,Hubei 430100,P R of China)
出处
《油田化学》
CAS
CSCD
北大核心
2021年第3期388-394,共7页
Oilfield Chemistry
基金
国家科技重大专项“海相碳酸盐岩超深油气井关键工程技术”(项目编号2017ZX05005-005)
中国石化科研项目“顺北一区采输关键技术研究与应用”(项目编号P18022-001)
“顺北一区5号断裂带提质提速钻完井技术研究”(项目编号P20002)。
关键词
无黏土相钻开液
改性淀粉
抗高温
增黏
降滤失
储层保护
clay-free drilling fluid
modified starch
high temperature resistance
viscosity increase
filtration reduction
reservoir protection
