Iranian Journal of Oil and Gas Science and Technology

Abstract Municipal and industrial wastewater possess potentially hazardous implications for the environment. Consequently, appropriate treatment measures must be implemented before its discharge into water bodies, onto land, or reuse. The provision of clean water constitutes a significant global priority. This investigation seeks to contribute to developing an efficient Wastewater Treatment Plant (WWTP). The implementation of technical simulation and modeling is of paramount importance in the design, construction, and prediction of the requisites for WWTP designs. Simulating a project before its implementation can mitigate additional expenses, and the project can be thoroughly assessed and scrutinized from various angles.

This examination proposes utilizing a combined nitrifying trickling filter/activated sludge (NTF/AS) process to modernize a Municipal Wastewater Treatment Plant (MWWTP). The performance of MWWTPs was analyzed and compared based on the combined rotating biological contactor (RBC)/AS process and the combined NTF/AS process. Two wastewater treatment plants were implanted and technically evaluated using data from the Ekbatan treatment plant in Tehran. In these scenarios, the GPS-X software was employed to explore the impact of variations in raw wastewater between their minimum and maximum intervals on the quality of effluent. Due to the divergence in the inlet effluent range, more precise outcomes were attained. In the fixed flow scenario, the RBC/AS wastewater treatment plant achieves removal percentages of 90.51, 89.7, 95.14, 14.8, and 76.41 for COD, TSS, BOD5, total phosphorus, and ammonia in the effluent, respectively.the RBC/AS method yields removal percentages of 92.2, 90.83, 97.22, 17.8, and 73.76 for the same parameters in the wastewater treatment plant. It is worth noting that both methods comply with Iranian standards, ensuring the quality of the effluent is suitable for discharge into the environment. One advantage of implementing the NTF method is the reduction in sludge yield.

Abstract This study presents an advanced petrophysical evaluation of the Sarvak Formation in one of the major supergiant oil fields in Southwest Iran, achieved by integrating Nuclear Magnetic Resonance (NMR) log data with conventional well logs. NMR measurements from Well-A were analysed to extract critical reservoir properties—including total and effective porosity, and volumes of bound and free water—which significantly enhanced the accuracy of the petrophysical model. A multi-resolution graph-based clustering (MRGC) algorithm was developed to estimate NMR-derived parameters from conventional logs for the adjacent Well-B, where NMR data were unavailable. The MRGC model utilised gamma-ray, acoustic, density, neutron, and photoelectric logs to predict total and effective porosity, clay-bound water, irreducible water saturation, and other NMR-related parameters. The model was calibrated using data from Well-A and subsequently applied to Well-B, enabling NMR-informed petrophysical characterisation in the absence of direct measurements. The optimised petrophysical model demonstrated consistent reservoir characteristics across both wells. Average total porosity was 10.7% in Well-A and 12.2% in Well-B; effective porosity averaged 10.2% and 11.8%, respectively; clay volume was approximately 3.2% in Well-A and 3.6% in Well-B; and water saturation was 85% and 84%, respectively. Based on cutoff thresholds of 5% porosity, 15% clay volume, and 50% water saturation, net pay intervals were delineated, yielding approximately 31 m of productive zone out of 411 m in Well-A, and 30 m out of 380 m in Well-B. The NMR-augmented analysis provided more precise differentiation of hydrocarbon-bearing zones and proved more cost-effective than traditional log-based methods. This refined petrophysical workflow significantly improves reservoir characterisation, enhances the accuracy of hydrocarbon volume estimation, and supports more informed field development planning.

Abstract In this study, nanostructured homogeneous and functionally graded (FG) Ni-Co/SiC coatings were fabricated on aluminum substrates via electrodeposition using a square pulse current. The FG coating was produced by continuously varying the concentration of SiC particles (0–40 g/L) in the electrolyte, resulting in a graded particle distribution across the coating thickness. The microstructure and morphology of the coatings were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Mechanical and electrochemical properties were evaluated through microhardness testing, T-peel adhesion testing, pin-on-disk wear testing, erosion testing, and potentiodynamic polarization and impedance spectroscopy. The results revealed that the SiC content in the FG coating gradually increased from 0 wt.% at the substrate interface to 6 wt.% at the surface. Compared to the homogeneous Ni-Co/SiC coatings, the FG coating demonstrated 40% higher adhesion strength and twice the wear resistance. Additionally, the FG coating exhibited improved corrosion resistance and overall mechanical performance, highlighting its potential for demanding industrial applications.

Abstract In this study, acid oil, which is a by-product of oil refinery waste was used for acid-catalyzed esterification to produce biodiesel. The reaction variables were methanol: acid oil molar ratio (1:1, 5:1, and 10:1), catalyst concentration (1%, 2%, and 3%), and reaction time (5, 30, and 60 min). Conversion yield, mass yield, free fatty acid (FFA) content, and physical properties (viscosity, density, refractive index, color attributes) of all the biodiesel samples were investigated. With increasing the methanol: acid oil molar ratio, catalyst concentration, and time, conversion yield and density increased, while free fatty acid content, viscosity and refractive index decreased, displaying an asymptotic trend toward equilibrium. At methanol: acid oil molar ratio of 10:1, catalyst concentration of 3%, and reaction time of 60 min, a near-maximum conversion yield of 95.3% was achieved. These conditions were considered optimum practical conditions, balancing biodiesel yield with operational and economic feasibility. Final yield of produced biodiesel at the practical optimum condition was 84.25%, which confirms that acid oil is a suitable feedstock for biodiesel production.