Research of a novel double cross-linking fracturing fluid

Yanrong Ge,Tao Liu,Xiupeng Guo,Tengfei Chen,Zhongcong Zhao,Xiaoliang Cheng

doi:10.1007/s13202-021-01167-5

Abstract

A kind of JDL-1 thickener for betaine hydrophobic association polymer was prepared by aqueous solution polymerization of mixed micelles, AM, AA, AMPS and DM16 were used as raw materials, which was synthesized by redox initiator system. Friction tester and high-temperature rheometer were used to evaluate the resistance reduction and temperature and shear resistance of the thickener. The results show that the viscosity average molecular weight of the polymer prepared with AM, AA, AMPS and DM16 mass ratio of 70∶20∶5∶5 was higher than 12 million, and the dissolution time of the polymer was less than 3 min. When the surfactant is used for physical cross-linking, the apparent viscosity of the cross-linked fracturing fluid is larger than that of 60 mPa·s at 90 °C, 170 s-1 sheared 1 h; when metal cross-linking agent is used for coordination cross-linking, the apparent viscosity is larger than that of 80 mPa·s at 120 °C, 170 s-1 sheared 1 h. The drag reduction rate was 73%, the anti-swelling rate was higher than70%, and the damage rate was less than10%. The field trial was successful and confirmed the multifunctional effect of betaine-type hydrophobic associating polymer.

Highlights

Fracturing fluid is a very important fluid for fracture and sand carrying during fracturing
On the basis of conventional aqueous solution polymerization process, a series of monomer compositions and ratios were designed according to the performance requirements of fracturing fluid for quick dissolution, drag reduction, cross-linking and sand carrying, so as to ensure that the relative molecular weight of the thickener can be controlled in an appropriate range, and the polymer has “linear main chain, proper side chain, slightly rigid and hydrophilic strong” molecular structure
According to the construction curve in Figs. (1, 4), the results showed that the construction displacement is 3 ~ 4 m3/min, the construction pressure is 40 ~ 50 MPa, and the highest sand carrying ratio is about 40%; 2) the average drag reduction rate is 72.5%, and the whole construction process is successfully completed without sand plugging, and the stable production capacity is good after fracturing; 3) the field trial was successful and confirmed the fracturing fluid can one agent multi-purpose

Summary

Introduction

Fracturing fluid is a very important fluid for fracture and sand carrying during fracturing. Traditional fracturing fluid is mainly guar gum fracturing fluid (Li et al 2019; Elkatatny et al 2018). Guar gum is becoming more and more expensive. With the development of unconventional oil and gas such as shale gas, tight gas and shale oil, new requirements are put forward for its the performance (Allison 2016; Wallace and Fritsch 2009; Bi et al 2013; Zhao and Dong 2016). In order to meet the fracturing requirements of complex formations, the fracturing fluids should be reformed and strengthened. It is necessary to study new fracturing fluid system (Qun et al 2020; Yang and Hou 2020; Mpelwa et al 2020; Cai Bo and Yun 2018; Yang et al 2015; Wang et al 2019)

Methods

Results

Conclusion