Journal of Applied Research of Chemical -Polymer Engineering

Abstract Research subject: One of the common problems in natural gas transmission lines is congestion and pressure drop in gas transmission pipes due to the formation of gas hydrates. Gas hydrates are stable crystalline compounds that are formed from the contact of water molecules with some gas molecules of the right size and under the right thermodynamic conditions (low temperature and high pressure). These compounds are studied from both thermodynamic and kinetic perspectives. Despite many studies in the thermodynamic part of hydrates, the kinetics of hydrates require further study.
Research approach: To this end, in order to determine the equilibrium conditions of natural gas hydrate, 5 different experiments were conducted with a natural gas sample from Gas and Liquefied Gas Refinery 1300 in the temperature range of 285.5, 281.5, 276.21, 275.59, 273.92 Kelvin and pressure of 41.1, 28.2, 18.84, 13.4, 11.5 bar in a reactor using the constant volume method.
Main results: Based on the experimental data, the mass transfer coefficient was 0.243, 0.159, 0.153, 0.094, 0.131 meters per second, respectively, and the molecular diffusion coefficient was 4.516(×10-09), 4.785(×10-09), 1.175(×10-09), 2.847(×10-09), 1.147(×10-09) m2/s. These results show that with increasing reactor temperature (at constant pressure), the mass transfer coefficient decreases and the molecular diffusion coefficient increases. Also, with increasing pressure (at constant temperature), the mass transfer coefficient increases and the molecular diffusion coefficient decreases, which is consistent with empirical equations. Statistical analysis of the results revealed that the reactor pressure parameter has a greater effect on the mass transfer coefficient than temperature. Furthermore, statistical examination showed that temperature is a more influential parameter on the molecular diffusion coefficient (DAB) of natural gas in water.

Abstract Research subject: Following the implementation of primary and secondary recovery processes in hydrocarbon reservoirs, enhanced oil recovery (EOR) methods are employed to increase extraction efficiency further. Among the most prominent techniques within this domain is chemical enhanced oil recovery (CEOR), encompassing well-established methods such as polymer flooding, polymer–surfactant hybrid flooding, polymer–nanoparticle flooding, and alkaline–surfactant–polymer (ASP) flooding. Despite their proven efficacy, these conventional approaches are often hindered by high operational costs, technical and operational complexities, and potential environmental concerns. In light of these challenges, polymeric surfactants have recently emerged as a promising and viable alternative, offering the dual functionality of viscosity enhancement and interfacial tension (IFT) reduction in a single agent.
Research approach: This study presents a comprehensive review and critical evaluation of recent research efforts concerning the application of polymeric surfactants in oil recovery processes. Key mechanisms, including viscosity modulation, IFT reduction, and wettability alteration, were systematically analyzed. Furthermore, limitations associated with the synthesis of these materials, elevated production costs, and the fragmented nature of available field data were considered. The review seeks to identify performance trends and knowledge gaps to guide future investigations.
Main results: The findings indicate that, under most reservoir conditions, polymeric surfactants have the potential to significantly improve oil recovery factors. However, their widespread implementation is currently constrained by complex synthesis procedures, economic barriers, and the lack of extensive field validation. This research synthesizes the latest advancements and offers recommendations for future work, including formulation optimization, cost-reduction strategies, and the design of large-scale field trials to assess real-world performance.