Zwitterionic Silica-Based Hybrid Nanoparticles for Filtration Control in Oil Drilling Conditions

Abstract

Water-based drilling fluids (WBDFs) that are susceptible to high temperature and saline pollution always exhibit poor ability to control fluid loss and seriously threaten the operation security of oil well drilling; especially, ultradeep well WBDFs that can simultaneously tolerate high salinity and temperature of over 200 °C are difficult to obtain. Herein, a zwitterionic silica-based hybrid nanomaterial (ZSHNM) with a spherical morphology (50−150 nm) was synthesized, and its filtration performance was thoroughly investigated. ZSHNM showed an extraordinary long-term (≥10 months) dispersion stability even at high concentrations in water and possessed remarkable tolerance to high temperature and salinity. Typically, merely adding 2 wt % ZSHNM in WBDFs could achieve an excellent filtration performance even at 240 °C, and with 11 wt % CaCl 2 or 36 wt % NaCl added, it showed the best performance to our knowledge. The results suggested that the sodium bentonite (Na-Bent) dispersion could be well stabilized in the presence of ZSHNM even at high temperature and with the presence of cations. Additionally, the silicate core could improve the thermal stability of ZSHNM, whereas the zwitterionic shell could form complexes with cations and further mitigate the aggregation of Na-Bent particles. Thus, the particle size distribution in WBDFs could be finely regulated similar to that in neat Na-Bent dispersion. Furthermore, given the zwitterionic ZSHNM filled in the micro−nanopores among the Na-Bent particles, a compact and lowpermeability filter cake was readily formed and ultimately reduced the drilling fluid loss during the filtration process. This work provided a versatile strategy to address the high temperature and high salinity tolerance of WBDFs synchronously, thereby pioneering a new way to develop high-performance drilling additives for ultradeep and complex wells.

Nanolaponite/Comb Polymer Composite as a Rheological Modifier for Water-Based Drilling Fluids

“…After adding LAP/P-TPEG, the interlayer spacing increased to 16.04 Å, which might be because the addition of LAP weakened the P-TPEG coating effect and enhanced the intercalation effect of the polyoxyethylene side chain, allowing full dispersion of the bentonite. The interlayer spacing was reduced to 12.86 Å due to the addition of NaCl, which reduced the water activity and osmotic pressure and inhibited the dispersion of bentonite . However, with the addition of P-TPEG, the polyoxyethylene side chains of the polymer were inserted into the lamellar layer, overcoming the influence of NaCl and restoring the interlayer spacing of bentonite.…”

“…With the addition of P-TPEG, the interlayer spacing of the bentonite sheets decreased by 13.92 Å. This might be attributed to the coating of bentonite particles by the comb polymer, 56 which somewhat inhibited the dispersion of bentonite. After adding LAP/P-TPEG, the interlayer spacing increased to 16.04 Å, which might be because the addition of LAP weakened the P-TPEG coating effect and enhanced the intercalation effect of the polyoxyethylene side chain, 27 allowing full dispersion of the bentonite.…”

“…The interlayer spacing was reduced to 12.86 Å due to the addition of NaCl, which reduced the water activity and osmotic pressure and inhibited the dispersion of bentonite. 56 However, with the addition of P-TPEG, the polyoxyethylene A good spatial network structure can improve the rheological properties of drilling fluids. 16,57 Bentonite was the basis for the drilling fluids.…”

Investigation on Filtration Control of Zwitterionic Polymer AADN in High Temperature High Pressure Water-Based Drilling Fluids

“…This may be due to the coating of BT particles by viscous AADN, which reduces the interlamellar distance of BT particles. With the addition of NaCl, the water activity and osmotic pressure decreased successively [ 43 ], decreasing d 001 to 12.52 Å, which reduced the hydration effect of BT particles. With the addition of AADN, which provides BT-DF with a salt-resistance effect that counteracts the effect of NaCl on BT particles, d 001 increased to 14.68 Å, and promoted the hydration and dispersion of BT particles.…”

Nano-Modified Polymer Gels as Temperature- and Salt-Resistant Fluid-Loss Additive for Water-Based Drilling Fluids

“…), organic nanomaterials (such as nanospheres, nano-gels, nano-emulsions, etc. ), and organic/inorganic composite nanomaterials, have been added into drilling fluids as filtrate reducers [ 27 , 28 , 29 , 30 , 31 , 32 ]. Furthermore, nanocomposites prepared by combining inorganic nanomaterials and polymers are especially beneficial for enhancing the dispersibility of nanomaterials and improving the temperature and salt resistance of polymers.…”