Aqueous Hybrids of Silica Nanoparticles and Hydrophobically Associating Hydrolyzed Polyacrylamide Used for EOR in High-Temperature and High-Salinity Reservoirs

Abstract

Water-soluble polymers are known to be used in chemically enhanced oil recovery (EOR) processes, but their applications are limited in high-temperature and high-salinity oil reservoirs because of their inherent poor salt tolerance and weak thermal stability. Hydrophobic association of partially hydrolyzed polyacryamide (HAHPAM) complexed with silica nanoparticles to prepare nano-hybrids is reported in this work. The rheological and enhanced oil recovery (EOR) properties of such hybrids were studied in comparison with HAHPAM under simulated high-temperature and high-salinity oil reservoir conditions (T: 85 °C; total dissolved solids: 32,868 mg873 mg•L −1 ). It was found that the apparent viscosity and elastic modulus of HAHPAM solutions increased with addition of silica nanoparticles, and HAHPAM/silica hybrids exhibit better shear resistance and long-term thermal stability than HAHPAM in synthetic brine. Moreover, core flooding tests show that HAHPAM/silica hybrid has a higher oil recovery factor than HAHPAM solution.

Studying the Effectiveness of Polyacrylamide (PAM) Application in Hydrocarbon Reservoirs at Different Operational Conditions

“…Among the chemical techniques that can be employed, polymer flooding applications are most commonly used for the control of fluid mobility in oilfield reservoirs [3,[5][6][7][8]. In an example of its use in China, over ten million tons of oil per year has been produced [1,[9][10][11]. Two of the most frequently applied synthetic water-soluble polymers are PAM and hydrolyzed PAM (HPAM).…”

Using Hybrid Silica Nanoparticles-Copolymer with Novel Micro-Model for Enhanced Oil Recovery

“…product has the segregated advantages of organic and inorganic materials, but hybrid mixtures can exhibit new properties not necessarily found in the individual components [15]. In addition to polymerization of the monomer in a suspension of inorganic particles (silica NPs), hybridization can also be obtained by swelling and gentle mixing of copolymer with side chain into silica NPs suspension [9]. In this way, we compare two di erent types of mixing of sulfonated copolymer and silica NPs to nd out which one is more e ective and results in a more powerful network to bear harsh conditions like high temperature.…”

“…The other way is modi cation of polymers with NPs additives to avoid time consumption or high cost of new polymer synthesizing. Zhu et al [9] reported application of NPs to increase the optical, thermal, magnetic, and electric properties of polymers. Attempts to nd additives for EOR purposes have been made by some researchers.…”

“…Maghzi et al [11,12] investigated dispersed silica NPs into polyacrylamide (PAM) in two types of laser and chemical MMs. Zhu et al [9] used core ooding test and checked hybridization of silica NPs and Hydrophobically Associating Hydrolyzed Polyacrylamide (HAPAM) in high-temperature and high-salinity reservoirs. In addition, Yousefvand and Jafari [13] showed that by adsorbing of SiO 2 NPs on pore walls, the wettability of MM changes to more Water-Wet (WW), so HPAM results in increasing RF.…”

Shear Resistance Properties of Modified Nano-SiO2/AA/AM Copolymer Oil Displacement Agent

“…Polymer flooding is an important technology to extend oilfield life and increase oilfield production [1][2][3][4][5][6][7][8]. As the most commonly used polymer in field applications, a small quantity of partially hydrolyzed polyacrylamide (HPAM) can increase the viscosity of water by 2 or more orders of magnitude in the absence of added electrolytes because of the extremely high molecular weight and the repulsion between the negative charges along the polymer chain [9].…”