Unveiling crude oil viscosity and rheological Properties: An experimental comparison of Nano silica and Nano Molybdenum disulfide in Bazargan Oilfield

The present study intends to experimentally investigate the impact of incorporating silica nanoparticles and Nano Molybdenum disulfide on the viscosity property and crude oil rheological properties of Bazargan crude oil (Iraq) at different nanoparticles concentrations and crude oil temperatures. The results indicate a notable reduction of crude oil viscosity as a result to adding the nanoparticles, increasing the nanoparticles concentration, and increasing the operating temperature. Statistically, the viscosity has been reduced from 57.15 cP at 25 °C to $31.27$ cP at 55 °C after adding 0.3 wt% of silica nanoparticles compared to a reduction of viscosity from 57.15 cP at 25 °C to 31.37 cP after the inclusion of 0.3 wt% of Nano Molybdenum disulfide at 55 °C. To quantify the estimation of viscosity reduction after the addition of nanoparticles, the degree of viscosity reduction (DVR%) is established. Specifically, the addition of silica nanoparticles assures the maximum DVR% of 31.58 %. using 0.3 wt% at 25 °C compared to the maximum DVR% of 29.27 % after the addition of 0.3 wt% of Nano Molybdenum disulfide.

A critical analysis of the crude oil rheological properties indicates that the crude oil can exhibit a Bingham fluid behavior. In this regard, the addition of nanoparticles at variable concentrations resulted in a decrease in yield stress, plastic viscosity, and effective viscosity. This proposes that the crude oil is transitioning towards Newtonian behavior, as demonstrated by the lessening yield stress and its gradual approach to zero after the combination of nanomaterials.