一种新型线性胶压裂液的室内评价及应用

Laboratory Evaluation and Application of A Novel Linear Gel Fracturing Fluid

从体系交联性能、耐温耐剪切性能、滤失性能、破胶性能、助排性能以及储层岩心伤害性能等对一种由人工合成的线性胶稠化剂配置而成的新型线性胶压裂液体系进行了室内评价,并在红河油田红河121井长81层进行了现场应用。室内评价结果及现场应用表明,新型线性胶压裂液体系携砂性好,60℃条件下连续剪切90min时压裂液黏度仍保持在100mPa·s左右;破胶彻底,残渣低,在储层温度下均能完全破胶,且180min内破胶液黏度均小于5mPa·s,60℃时破胶后的残渣含量为18mg/L;破胶液黏土防膨效果较强,防膨率达到82.5%;破胶液表、界面张力较低,55℃时,破胶液的表面张力为26.7mN/m,界面张力为1.24mN/m,利于压后返排;破胶液对岩心平均伤害率仅为15.3%,伤害较低,该压裂液既能满足现场压裂施工和压后快速破胶返排的需要,又利于保护储层。

Based on the characteristics of cross linking performance,temperature and sheer resistant properties,filtration property,gel breaking performance,cleanup performance and reservoir core damage property of the fracturing system,a fracturing fluid system which is composed of a linear gel gelatinizer of synthesized/manually is evaluated in the laboratory and field application is carried out in Chang 81 Reservoir in Well Honghe 121 of Honghe Oilfield.The results of the laboratory evaluation and field application show that a novel linear gel fracturing fluid system has good carrying ability,the fracturing fluid viscosity remains at about 100mPa·s under the condition of continuous shearing for 90 min at 60℃,its gel breaking is complete with low residue,its gel breaking is complete at reservoir temperature and the viscosity of gel breaking liquid is less than 5mPa·s in 180 min,the residue content is 18mg/L after gel breaking at 60℃,its clay antiswelling effect is strong with anti swelling rate of 82.5%;its interfacial and surface tensions are low,the surface tension is 26.7mN/m and the interfacial tension is 1.24mN/m at 55℃,it is favor of postfrac flowback,the average core damage is as low as 15.3%.These advantages not only can meet the needs of fast breaking in field fracturing and and also can protect the reservoirs.