Experimental Investigation of a Novel Nanocomposite Particle Gel for Water Shutoff Treatment in Mature Oilfields

Abstract

Conventional preformed particle gels suffer from insufficient salt tolerance and weak mechanical properties after water absorption, which reduce the water shutoff effect in mature oilfields. In this paper, a nanocomposite particle gel (NCPG) is synthesized by copolymerization of acrylamide (AM) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) using laponite RD (LPT) as a physical cross-linker and N,N-methylene-bisacrylamide (MBA) as a chemical cross-linker via in situ free radical polymerization. Compared with the NCPG without LPT, both the swelling rate and mechanical properties of NCPG added with LPT are found to be improved. In addition, the pore sizes of the network of the swollen NCPG are smaller than those of the sample without LPT, and the thermal stability is also slightly enhanced. The swelling rate of NCPG increases with increasing AMPS concentration. The water absorbency of NCPG first increases and then decreases with increasing MBA and APS concentrations. The NCPG is sensitive to alkaline medium due to the presence of sulfonic acid groups on the molecular chains of the NCPG. The synthesized NCPG exhibits good salt tolerance at 80 °C in formation water. The plugging rate of the NCPG to a sand-pack is above 90%, and the residual resistance factor reaches 19.2 under reservoir conditions. These results indicate that the NCPG may have potential application for water shutoff treatment in mature oilfields.

Biodegradable Preformed Particle Gel (PPG) Made of Natural Chitosan Material for Water Shut-Off Application

“…However, increasing the temperature and the thermal hydrolysis beyond the optimum conditions will open up more of the 3D network structure, leading to losses in the polymer chain's connections and, thus, less water loss or syneresis and a lower swelling ratio [14]. Contrary to others, PAM6.5%/Cs0.25% is most susceptible to polymer chain ruptures and syn- When comparing the behavior of PAM/Cs PPG in saline conditions with other PPG systems in the literature [17,23,25,42], one can notice their good behavior in terms of swelling capacity and ultimate strength, besides their non-toxicity property. In HSW, the TDS of 67.2976 g/L, the swelling ratios of PAM/Cs vary from 12.22 to 18.73 g/g, and the strengths are from 2052.9 to 5980.2 Pa.…”

“…Nevertheless, polyacrylamide, polyacrylic acid, and the co-polymer combining are the most abundant. Typically, organic crosslinkers such as N, N-methylene bis-acrylamide [18,23,24] or inorganic crosslinkers [14,25] are utilized in the process of PPG's production. Some PPGs share formulations or crosslinkers with those used in the in-situ gels, such as polyethylenimine [19], chromium acetate [25], and aluminum nitrate [14], which indicates that the formulations of the current in-situ gels might also develop PPGs for water shut-off treatment, having the advantage of being PPG.…”

Development of Inorganically Cross-Linked Sulfonated Polyacrylamide Preformed Particle Gels for Conformance Control: Impact of Anionic Groups

“…This leads to an earlier equilibrium state with a lower swelling ratio than freshwater. Parallel studies have verified that utilizing saline solutions as swelling media decelerates the PPG swelling rate. − Moreover, the quicker swelling kinetics of AlLc PPG, as observed in freshwater and seawater, can be attributed to its denser network structure than others. This increased density restricts water inflow, facilitating the faster attainment of its equilibrium swelling capacity.…”

Titanium Dioxide Nanomaterial-Reinforced Particle Gel: Development, Characterization, and Performance Evaluation for Water Shutoff Jobs in Heterogeneous Reservoirs

“…It can be observed that the degradation temperature of the NR-PPG sample is shifted toward a higher temperature when compared to the WR-PPG sample. 33,51 Furthermore, the DTG graph (Figure 14) shows that the highest loss for WR-PPG was recorded at 371 °C. In contrast, a similar type of deterioration peak was found for the NR-PPG sample at 377 °C.…”