疏水缔合物在压裂液中的应用

THE APPLICATION OF HYDROPHOBIC ASSOCIATING WATER- SOLUBLE POLYMER IN THE FRACTURING FLUID

疏水缔合型压裂液作为一类新型低伤害压裂液体系,由于其独特的流变性能应用在压裂改造中。讨论了稠化剂、盐对基液表观粘度的影响。随着盐浓度的增加,基液表观粘度降低;120℃缔合基压裂液在该温度下,170S-1的剪切速率下连续剪切2h后,表观粘度为43mPa.s;150℃缔合基压裂液在该温度下,170S-1的剪切速率下连续剪切100min后,表观粘度为40 mPa.s;该配方具有较好的耐温耐剪切特性。通过粘弹性测试得出该结构流体在整个扫描过程中储能模量高于损耗模量,表现出以弹性行为为主。少量破胶剂即可使压裂液在4h后完全破胶,且破胶液粘度小于5mPa.s。破胶液的固相含量为零,残渣含量极低,与常规瓜胶压裂液相比,降低了液体对地层的伤害。

Hydrophobic associating water- soluble polymer based on fracturing fluid is a new type of low damage fracturing fluid. Because of the distinctive rheological characters,it is applied in the hydraulic fracturing. The influences of viscosifier and salt on the fracturing fluid's apparent viscosity are discussed. As the content of salt increased,the apparent viscosity decreased. When the temperature increases to 120℃,the apparent viscosity of fracturing fluid is 43 mPa. s at the shear rate of 170 seconds after two hours. When the temperature increases150℃,the apparent viscosity of fracturing fluid is 40 mPa. s at the shear rate of 170 after 100 minutes. When the temperature increases,the apparent viscosity decreases. This fluid has good stabilities of temperature、shearing and time,and is well satisfied at high temperature formation. By the way of the test of viscoelastic character,thestorage modulu is higher than the wastage modulu. This fluid focuses on the behavior of elastic. The good ability of carrying sand is showed as the apparent viscosity is a little low. The fracturing fluid will totally break after 4hours. The apparent viscosity of break fluid is less than 5mPa. s. The content of solid in the break fluid is zero.Because the residue of fracturing fluid is very low,the formation damage will relatively decrease,compared to conventional guar fracturing fluid.