Journal of Oil, Gas and Petrochemical Technology
سال دهم شماره 2 (Summer and Autumn 2023)

Atom Transfer Radical Polymerization (ATRP) is a beneficial technique for the preparation and design of multifunctional and nanostructured materials for a variety of applications. Macromolecular structure, order and functionality are of the most important factors and considerations in polymer science and ATRP enables precise control over these factors. This method aids synthesizing novel engineering polymeric materials which play an absolutely essential role in all aspects of our lives and there is a “must” to develop new and green methods to synthesize and produce novel materials as best as we can. In this research, we have synthesized novel graft copolymers of PVDF-g-PS and PVDF-g-PSSA via ATRP which have a variety of applications from membranes to Li-Ion batteries. These materials can be used to enhance the properties of Li-ion batteries’ separator operation. The characterization of the final copolymers was performed using Fourier transform infrared spectroscopy (FT-IR) and 1H nuclear magnetic resonance (1H-NMR) analyses. The grafting percentages obtained from 1H-NMR analyses are reported to be 2%, 13% and 44% for PVDF-g-PS (I), PVDF-g-PS (II) and PVDF-g-PSSA copolymer samples, respectively.

The measurement of shear wave velocity (Vs) using the dipole sonic imager (DSI) logging tool is regarded as a crucial physical parameter for rocks. However, not all wells have access to this data, making it essential to accurately and reliably estimate this parameter with minimal uncertainty to determine reservoir characteristics effectively. The Vs estimation approach in this study includes empirical methods and two rock physic models. In empirical methods, empirical correlations reported in studies have been used. In the second approach, two rock physics models, Gaussmann and Xu-Payne, which are more complicated than the experimental models, have been chosen to determine the characteristics of the Vs. The main innovation of this paper is the comparison of all the mentioned methods in Vs estimation. Correlation coefficient (R2) and Average Relative Error (ARE) were chosen as statistical comparison criteria. Based on the final findings, the Greenberg and Castagna method, incorporating Gaussmann fluid replacement theory, exhibited consistent performance and improved estimation accuracy of Vs with R2 and ARE values of 0.9067 and 3.2292, respectively. The suggested approach has the potential to be employed in various other oil and gas exploration fields and can provide accurate Vs estimates.

In the present study, acrylamide/2-acrylamido-2-methylpropane sulfonic acid (AM/AMPS) copolymers were synthesized for enhanced oil recovery (EOR). The effects of silica nanoparticles (SNPs) on the copolymer solution viscosity and oil recovery factor was investigated. Chemical structure of the copolymers and viscosity of the resultant aqueous solutions were determined using Fourier-transform Infrared (FTIR) spectrometer and an Ostwald viscometer, respectively. The functionality of the AMP55 copolymer in polymer injection test was studied using a glass micromodel. Oil recovery factor of 62.3% was obtained for injection of AMP55 copolymer. Additionally, the effect of SNPs on the solution viscosity and oil sweeping efficiency was studied. For this purpose, various amounts of SNPs (1, 2, and 3 wt.%) were added to the solutions with different AMP55 concentrations. Rheological results showed that incorporation of 2 wt.% of SNPs resulted in maximum viscosity of 42.8cs. Injection test results indicated that introduction of the 2 wt.% SNPs in the AMP55 solution enhanced the sweeping efficiency (71.7%) and recovery factor 15% and 400%, compared to the SNPs free copolymer solution and water flooding, respectively. The experiments led to proper selection of the synthesized copolymer structure and SNPs content in its solution, to attain the maximum viscosity and oil sweeping efficiency.

Liquid-liquid extraction is one of the main separation processes which has many applications in different industries. Among different influencing parameters on Liquid-liquid performance, the surface tension effect was investigated in the present study. The mass transfer of a single droplet was simulated using the volume of fluid approach coupled with a single-field mass transfer approach.  Due to the high computational time, the moving reference frame approach was supplemented to computational codes in parallel processing mode assuming static droplet and moving zone. The results showed that with the reduction of surface tension coefficient, while the other parameters were kept constant, the regime change from spherical to oscillating occurred, the velocity decreased. In addition, along with an additional reduction in the surface tension coefficient, the droplet breakage happened. Despite a considerable reduction in terminal velocity, the reduction in mass transfer was not observed due to the interfacial area increase which enhanced mass transfer while velocity reduction negatively disturbed it. The concentration contour plots of droplets in various surface tension coefficients were reported in different droplet regimes starting from circulating to breakup.