SiO_(2)纳米粒子型低浓度阳离子表面活性剂压裂液研究  

Study on SiO_(2) Nanoparticle Type Low Concentration Cationic Surfactant Fracturing Fluid

作　　者：张霜霜 东野升富 徐灿[3] 周平 赵梦龙 李建元 ZHANG Shuangshuang;DONGYE Shengfu;XU Can;ZHOU Ping;ZHAO Menglong;LI Jianyuan(College of Petroleum Engineering,University of Yangtze,Wuhan,Hubei 430100,China;No.2 Oil Production Plant of PetroChina Changqing Oilfield Branch,Shaanxi,Xi’an 744100,China;No.5 Oil Production Plant of PetroChina Changqing Oilfield Branch,Shaanxi,Xi’an,710200,China;No.5 Oil Production Plant of PetroChina Qinghai Oilfield Branch,Mangya,Qinghai 816499,China;Drilling and Production Technology Research Institute of PetroChina Qinghai Oilfield Company,Dunhuang,Gansu 736202,China;No.4 Oil Production Plant of PetroChina Qinghai Oilfield Company,Mangya,Qinghai 816499,China)

机构地区：[1]长江大学地球科学学院 [2]中国石油长庆油田分公司第二采油厂 [3]中国石油长庆油田分公司第五采油厂 [4]中国石油青海油田分公司采油五厂 [5]中国石油青海油田分公司钻采工艺研究院 [6]中国石油青海油田分公司采油四厂

出　　处：《钻采工艺》2021年第2期102-106,共5页Drilling & Production Technology

基　　金：国家科技重大专项“大型油气田及煤层气开发”(编号:2016ZX05007-002)。

摘　　要：黏弹性表面活性剂(VES)压裂液由于具有无残渣、低摩擦、破胶完全等优点,越来越受到人们的重视。然而,由于价格高、耗用量大,进一步限制了VES的广泛应用,本研究提出了SiO_(2)纳米粒子低浓度VES压裂液(NAVES)。由1%EDAA和0.01%SiO_(2)组成的NAVES体系在70℃下剪切2 h黏度在33 mPa·s以上;而1%EDAA在相同条件下黏度为24 mPa·s,这是由于表面活性剂胶束附着在带负电的SiO_(2)纳米颗粒的表面上,通过静电相互作用形成动态网络结构,所以NAVES体系比EDAA体系具有更高的黏度。黏弹性测试也证实了SiO_(2)与胶束的伪交联可以提高EDAA的抗剪切性能和弛豫时间。NAVES体系在100 min内可以完全破碎,其黏度降低到5 mPa·s以下。25℃时,EDAA/SiO_(2)体系中石英砂的沉降速率为0.0021 cm/s,低于传统的VES压裂液,因此,NAVES可以作为低浓度的水力压裂液。Attributing to its advantages including no residue,low friction and complete gel breaking,viscoelastic surfactant(VES)fracturing fluids are attracting more and more attention.However,due to the high price and high consumption the wide application of VES is further restricted.SiO_(2) nanoparticle-assisted VES fracturing fluid(NAVES)with low concentration is proposed in this study.The NAVES system consisting of 1%EDAA and 0.01%SiO_(2) maintains a shear viscosity of above 33 mPa·s at 70℃for 2 h;in contrast,the viscosity of a 1%EDAA(VES)solution is 24 mPa·s at 70℃for 2 h.This could be attributing to the formation of a strong dynamic network structure,in which the surfactant micelles attach to the surface of SiO_(2) nano-particles that are negatively charged through electrostatic interactions.Therefore,the NAVES system has higher viscosity than the EDAA system.The viscoelastic test also confirmed that the pseudo-cross-linking of SiO_(2) and micelles can improve the shear resistance and relaxation time of EDAA.The NAVES system could break completely within 100 min,as reflected by the fact that its viscosity decreased to less than 5 mPa·s.The settling rate of quartz sand in an EDAA/SiO_(2) system at 25℃was 0.0021 cm/s,which was lower than that of traditional VES fracturing fluid.Therefore,NAVES could serve as a low-concentration hydraulic fracturing fluid.

关 键 词：阳离子表面活性剂 SiO_(2)纳米颗粒 压裂液 黏弹性 流变学 

分 类 号：TE357.12[石油与天然气工程—油气田开发工程]