Modified Biosurfactant Cationic Alkyl Polyglycoside as an Effective Additive for Inhibition of Highly Reactive Shale

Abstract

The wellbore instability caused by shale hydration in highly reactive shale formation is a troublesome problem during the oil and gas drilling process. In this study, cationic alkyl polyglycoside (CAPG) was synthesized by the etherification of C4 APG and applied to inhibit shale hydration. Using a highly reactive shale sample, the inhibiting performance of CAPG was studied by the mud ball immersing test, linear swelling test, shale recovery test, and bentonite inhibition test. The inhibiting mechanism was studied by experiments of surface tension, contact angle, particle size, X-ray diffraction, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy. Evaluation of experimental results proved that CAPG had the best inhibition performance for highly reactive shale among the inhibitors studied in this work. Especially, CAPG has a substantially higher shale recovery ratio of 87.08%, while the shale recovery ratio of water is merely 5.41%. According to the mechanism analysis, the excellent inhibition performances of CAPG could be explained in three aspects. First, CAPG could reduce surface tension, reducing water infiltration into shale caused by capillary pressure. Second, CAPG could enter interlayer spaces of bentonite. The multipoint adsorption of CAPG on the clay surface caused by electrostatic attraction and hydrogen bonding could isolate water and neutralize negative charges on the clay surface, which is beneficial in reducing both surface hydration and osmotic hydration of clay. Third, CAPG could substantially decrease porosity of the shale surface according to SEM, reducing water invasion, which is probably because the CAPG aggregates (particle size is 248.5 nm for 1 wt % solution) plug shale pores. This paper provided an effective method to inhibit highly reactive shale.

Laponite: a promising nanomaterial to formulate high-performance water-based drilling fluids

“…Shale inhibitor is widely used in WBF to reduce hydration and swelling of clay. The existing inhibitors include inorganic salts, surfactants (Lv et al 2020;Shadizadeh et al 2015), polymers, alcohols, and polyamines (Jiang et al 2016;Zhong et al 2016), which reduce shale hydration by charge neutralization, wettability reversal, forming isolated layers, reducing surface tension, etc.…”

Oxygen-Vacancy-Rich BiO2–x/Ag3PO4/CNT Composite for Polycyclic Aromatic Hydrocarbons (PAHs) Removal via Visible and Near-Infrared Light Irradiation

“…The interaction between the functional groups of CNT, Ag 3 pO 4 , and BiO 2– x was evidenced by FT-IR spectroscopy. For CNT, the stretching vibration of −OH group shows a distinct absorption peak at 3430 cm –1 . , Two absorption peaks located at around 1708 and 1647 cm –1 , corresponding to the – CO and – COOH groups on CNT surface, , as shown in Figure . Detail information can be seen in the enlarged perspective view of Figure .…”

Preparation and Performance of the Hyperbranched Polyamine as an Effective Shale Inhibitor for Water-Based Drilling Fluid

“…The ability of the inhibitor to prevent shale hydration swelling can be detected by the changing rules of yield points for bentonite slurries with various concentrations [11] [12] [13]. The evaluation results of the bentonite inhibition test were shown in Figure 3.…”