Rheological and transport properties of sulfonated polyacrylamide hydrogels for water shutoff in porous media

Abstract

In this research, an optimal hydrogel, based on sulfonated polyacrylamide, was synthesized by statistical design of experiments using central composite method. This new hydrogel composed of sulfonated polyacrylamide (AN125VLM) and chromium triacetate as copolymer and crosslinker, respectively. The bottle and rheological tests were conducted to investigate the gelation time, thermal stability, gel strength and also ultimate elastic modulus, complex modulus, and yield stress. It was found that copolymer concentration had the main effect in both rheological and transport properties of hydrogels. The sample prepared at optimum condition, i.e. copolymer concentration of 26,340 ppm and crosslinker/copolymer ratio of 0.12, had an ultimate elastic modulus of 29.9 kPa, yield stress of 800 Pa, and complex modulus of 32 kPa. A coreflooding test through fracture was carried out to examine the optimum gel performance in a porous media. A value of 483 for the residual resistance factor ratio of water to oil confirmed the high ability of the hydrogel in reducing the relative permeability of water to oil in fractured media.

Synthesis, characterization and evaluation of polyacrylamide graft starch/clay nanocomposite hydrogel system for enhanced oil recovery

“…The efficiency and plugging capacity of hydrogel systems were determined by the residual resistance factor (F rr ) for water and oil and the percentage reduction in permeability, respectively. These studies determined the effect of gel on the absolute permeability of the sand pack, and the water shutoff efficiency was determined using the same procedure as followed by several researchers working in this area Salehi et al 2014;You et al 2015).…”

“…The residual resistance factor (F rr ) is a measure of permeability reduction and calculated using the following equations (Mohammadi et al 2015;Salehi et al 2014):…”

“…Water control is a key issue in most of hydrocarbon reservoirs (Liu et al 2010;Salehi et al 2014;Yadav and Mahto 2013a). Polymer gels are widely used to control water production by blocking the high-permeability zones in heterogeneous mature reservoirs and then diverting the water to the low-permeability zones during enhanced oil recovery operations.…”

Study of the polymer concentration and polymer/crosslinker ratio effect on gelation time of a novel grafted polymer gel for water shutoff using a central composite design method

“…That system, firstly, was proposed for reducing water permeability and consequently increasing oil sweep efficiency in enhanced oil operations. [10][11][12][13] For the well treatment, selection of a polymer gel system strongly depends on reservoir conditions such as temperature, hardness, salinity, and the pH of the water used for preparation of the gelant. There are other parameters that could be considered for the proper selection of a given polymer gel system such as permeability of the target zone, salinity of the formation water, and the lithology of the formation.…”

Preparation and probing of the steady shear flow and viscoelastic properties of weakly crosslinked hydrogels based on sulfonated polyacrylamide for oil recovery applications

“…Partially hydrolyzed polyacrylamide (HPAM) and sulfonated polyacrylamide (SPA) are well known water soluble and commercially available polymers whose solutions and gels are employed in many com mercial applications, especially for enhanced oil recovery and control of the excess water production through profile modification and blocking the paths with high permeability to water [3][4][5][6][7][8][9][10][11][12][13][14].…”