Experimental Investigation on the Nanosilica-Reinforcing Polyacrylamide/Polyethylenimine Hydrogel for Water Shutoff Treatment

Abstract

Polyacrylamide hydrogel used in conformance control is subjected to poor stability at an elevated temperature. In this paper, nanosilica has been found to be a very effective stabilizing agent for the polyacrylamide/polyethylenimine hydrogel, and the reinforcing performance of nanosilica on the hydrogel was investigated in detail. The result showed that the strength of hydrogel is enhanced obviously by the nanosilica, and the hydrogel syneresis is also significantly inhibited by the nanosilica, which can increase the hydrogel stability time from 18 to 180 days at 130 °C. Besides, nanosilica can increase the shear viscosity and hydrodynamic radius of polyacrylamide, and the bound water in the hydrogel is also grown in the presence of nanosilica. In comparison to the micromorphology of common hydrogel, the dense and strong mesh structure is formed as a result of the reinforcing behavior of nanosilica. According to the above results, it is inferred that the silanol group of nanosilica cross-links with the amidogen of polyacrylamide via the hydrogen bond, which is considered as the primary cause of the reinforcing performance of nanosilica for the hydrogel. In addition, as a result of the improving strength and stability and increasing absorption of the polymer to rock surface, the hydrogel enhanced by nanosilica has a higher water shutoff ratio and residual resistance factor and a longer period of validity.

Applications of Graphene and Its Derivatives in the Upstream Oil and Gas Industry: A Systematic Review

“…The construction of oil flooding systems based on new materials has always been the main direction of the development of chemical flooding for oil recovery. The application of nanoparticles in CEOR, which has developed rapidly in the past two decades, provides the basis for the application of graphene materials in CEOR [79][80][81][82]. The following studies show that the use of graphene and its derivatives is feasible in chemical enhanced oil recovery.…”

Behavior of partially hydrolyzed polyacrylamide/polyethyleneimine reinforced with coal fly ash for preformed particle hydrogels

“…A similar proposal for PHPA/PEI-based gel formation can be seen in the literature. [10,14,24] Rheological analysis-Initially, to determine the properties in the oscillatory regime, a strain sweep was carried out to determine the linear viscoelasticity region in the conventional gel obtained with low molar mass PHPA (Pure L Gel). Figure 6 shows the storage (G') and loss (G") moduli obtained and the limit of the linear viscoelasticity region.…”

“…[10] Nevertheless, because of the soft and fragile nature of hydrogels, studies have focused on developing new polymeric hydrogels reinforced with fillers that have improved mechanical properties. [8,11] Numerous studies with different fillers exist, among them silica, [12,13,14,15] clay, [16,17,18] and coal fly ash (CFA). [19,20,21] CFA is a fine particle from the combustion of pulverized coal in power plants.…”

Polyvinylpyrrolidone-resorcinol-formaldehyde hydrogel system reinforced with bio-synthesized zinc-oxide for water shut-off in heterogeneous reservoir: An experimental investigation

“…Most of the researchers developed and widely studied nanocomposite hydrogels by reinforcing fillers in the hydrogel matrix. Among the most commonly used reinforced materials are nano-silica (Chen et al, 2018;Lashari et al, 2018), fly ash (Jiang and Liu, 2014;Singh et al, 2018), clays (Aalaie et al, 2008;Helvacıoğlu et al, 2011;Okay and Oppermann, 2007;Tongwa et al, 2013), and carbon nanotubes (Evingür and Pekcan, 2014;Li et al, 2016;Sudha et al, 2014). However, organically modified fillers were also used to enhance the properties of hydrogel (Helvacıoğlu et al, 2011;Rezaei et al, 2016).…”