Study of a Novel Self-Thickening Polymer for Improved Oil Recovery

Abstract

The utilization of self-thickening polymer (STP) in conformance control was first investigated. Results show that these STP solutions exhibit an increase in viscosity (even like gel) under certain conditions. The optimized application conditions of this novel STP are as follows: mass concentration, 0.25−0.30 wt %; salinity, 4.0−8.0 wt %; and temperature range, 40−70°C. Environmental scanning images demonstrate that a clear and solid skeleton network structure is formed and the higher the salinity of the brine, the more compact the three-dimensional (3D) network structure. In addition, in-depth flow diversion and water permeability reduction were the main mechanisms of water shut-off treatment for improved oil recovery in oil displacement experiments. Finally, this novel STP with the ability to create a gel-like system is cost-competitive, simpler to apply, and more environmentally friendly than the current polymer−cross-linker system. It provides an alternative candidate for conformance control treatments at injection or production wells.

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).…”

“…Normally, the capacity of the gel system for water shutoff or water shutoff efficiency can be evaluated by the reduction in permeability of the sand pack after the gel treatment (Chen et al 2015;Kang et al 2015;Karimi et al 2014;Li et al 2016;You et al 2015), which is defined as:…”

Using State Functions and MRST’ls AD-OO Framework to Implement Simulators for Chemical EOR

“…Salinity effects: Like temperature, changes in salt ion type and concentration also affect the properties of polymers and surfactants [40]. For polymers, the viscosityincreasing effect changes with different salt ion concentration; usually the viscosity decreases, but a few special polymers have salt-sensitive self-thickening effects [41]. For surfactants, the presence of salt ions not only impacts the reduction in interfacial tension and the wettability alteration but also plays an important role in the phase behavior and properties of microemulsion.…”

Salt tolerant acrylamide-based quenched polyampholytes for polymer flooding

“…The most widely used synthetic EOR polymer is polyacrylamide (PAA) and its derivatives [9][10][11][12]. This polymer is usually used in hydrolyzed polyacrylamide (HPAM) form to achieve higher viscosity within a certain range of brine salinities [13].…”