Synthesis and performance evaluation of crosslinker for seawater‐based fracturing fluid

Abstract

Zirconium is one of the most commonly used crosslinkers for guar gum‐based fracturing fluid. Nevertheless, it is difficult for zirconium crosslinkers applied in fracturing to possess both high temperature resistance and adjustable crosslinking time. Meanwhile, few people did systematical research on the crosslinking process of fracturing fluid. In this study, an organic zirconium crosslinker with high temperature resistance and controllable crosslinking time was synthesized. The seawater‐based fracturing fluid gel prepared with the crosslinker could perform well under 170°C. Oscillatory shear experiments were conducted to analyze the rheology of the gelation process. Moreover, steady‐state shear and micro‐rheological tests were conducted to analyze the dynamic and static crosslinking process of the fracturing fluid, respectively. Meanwhile, rheo‐kinetic equation was used to fit the data and the effects that various factors had on the gelation process were illustrated thoroughly. This study not only prepared an organic zirconium crosslinker with good performances, but also explored the crosslinking process of fracturing fluid gel, which could improve its further application in oilfields.

Preparation and laboratory study of a sodium carboxymethyl cellulose smart temperature‐controlled crosslinked gel fracturing fluid system

“…According to a large number of related literature surveys, 26–28 we conducted experiments with a substance ratio of water to glycerol of 12:1–16:1. The fixed solute ratio, reaction temperature and reaction time were 3:1, 80°C and 5 h. The experimental results are shown in Figure 2b.…”

Review on High-Temperature-Resistant Viscoelastic Surfactant Fracturing Fluids: State-of-the-Art and Perspectives

“…Zhang et al reported that the insoluble content of guar gum derivatives decreased to 5 wt % . Among guar gum derivatives, hydroxypropyl guar gum (HPG) and carboxymethyl hydroxypropyl guar gum (CMHPG) are widely used in hydraulic fracturing due to their ease of hydration and low residue content. − The boron, zirconium, and titanium cross-linkers − are often used to cross-link guar-based fracturing fluids to enhance their elasticity and viscosity without increasing polymer concentration . The cross-linked polymers have better viscosity and proppant carrying capacity than linear gel but have greater damage to fracture conductivity (>38%). − In addition, the cross-linking process requires a specific pH environment and cross-linking time control …”

Seawater-Based Fracturing Fluid: A Review

“…Fourier transform infrared (FT-IR) and ultraviolet−visible (UV−vis) spectroscopy analyses confirmed that the ligands successfully bonded to the zirconium ions. 86 In yet another study, a fracturing fluid was manufactured with a stable operating temperature of 350 °F at 30 lb/1000 gal by mixing CMHPG with synthetic polymers (AA-AM-AMPS). 81 The cross-linker−polymer strength was able to be maintained at temperatures exceeding 350 °F by using a zirconium cross-linker that reacted slowly.…”

“…The CHKO 2 -weighted fracturing fluid created with the composite cross-linker showed excellent performance in static filtration loss and formation damage, as well as the capacity to preserve a high viscosity at 320 °F. In another study, an organic zirconium cross-linker with seawater compatibility was evaluated . The gel for fracturing was made by combining a CMHPG fluid based on seawater with an organic zirconium cross-linker.…”

“…In another study, an organic zirconium cross-linker with seawater compatibility was evaluated. 86 The gel for fracturing was made by combining a CMHPG fluid based on seawater with an organic zirconium cross-linker. Fourier transform infrared (FT-IR) and ultraviolet–visible (UV–vis) spectroscopy analyses confirmed that the ligands successfully bonded to the zirconium ions.…”