Experimental evaluation of bentonite clay swelling and inhibition effect of nanoparticles

Formation damage due to clay minerals swelling and migration is one of the major challenges in shaly reservoirs. The main objective of this study was to explore the potential of nanoparticles application as clay swelling inhibitor and investigate the effect of various parameters on nanoparticles performance. The experiments were designed using Taguchi orthogonal array and the impact of the main factors, including pH value, salinity, and temperature, and the presence of nanoparticles with concentrations of 0.05-1 wt% was inspected on the clay swelling. Zeta potential measurements were used to determine the surface charge of nanoparticles at different pH values. XRD and XRF analyses were carried out to characterize the nanoparticles and bentonite powder. The experimental results showed that after solution salinity, the most effective parameter on the clay swelling is the concentration of nanoparticles. The minimum clay swelling index was obtained in the presence of silica nanoparticles at 0.1 wt% concentration. It was observed that higher concentrations of nanoparticles not only have no effect on reducing the clay swelling but also increase the volume due to nanoparticles agglomeration. The presence of alumina nanoparticles showed an inverse effect on the clay swelling and increased the swelling index. The results of zeta potential measurements indicated that nanoparticles with negative surface charge help to decrease the clay swelling as the result of similar charge repulsion. The low swelling index detected in samples containing silica nanoparticles shows the potential of nanoparticles to prevent the formation damage due to clay swelling.

Automated summary

The study aimed to investigate the potential of nanoparticles as clay swelling inhibitors and explore the impact of various parameters on their performance. The experiments showed that nanoparticles, particularly silica nanoparticles at the appropriate concentration, can effectively reduce clay swelling and prevent formation damage.