Iranian Journal of Oil and Gas Science and Technology

Abstract Process pipelines are essential for operations, but their failures can have severe consequences. This study investigates and analyzes the consequence modeling of the pipeline corridor located in southern Iran. It also determines the restricted and impacted areas around the pipelines using PHAST software. The consequence modeling of the main scenarios, including flammable and toxic gas dispersion, fire, and explosion, is analyzed. According to the results, the restricted and impacted areas around the pipelines are 426.9 meters and 454.3 meters for section 1, and 648 meters and 802 meters for section 2, respectively.

Following the results, preventive and mitigative measures are recommended to lower risks. Multiple strategies should be employed to reduce the risks associated with the pipelines. Some strategies aim to decrease the frequency of incidents, while others focus on reducing the impacts and consequences of leakage, rupture, or any other type of containment failure.

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 Chlorine is a toxic and oxidizing gas used to purify drinking water in Iran. There has been no research on the effects of the gas or the explosion of the tanks, which could cause irreparable damage to people and the surrounding area. No such study has been carried out in the city of Abadan. To this end, Areal Locations of Hazardous Atmospheres (ALOHA) software, a computer program that helps professionals understand what will happen during a hazardous release, such as a chemical or fire, allows them to make plans to keep people safe. Thus, it was used to assess the magnitude of the gas release, the various risk zones, and the population at risk. In the event of damage to the 1-inch outlet valve of the tank, the gas release could be lethal up to a radius of 2 km, could be effective up to a radius of 6.2 km, and could be felt up to 10 km away. Due to the probability of occurrence and the location of the station in the wind direction, gas could reach many residents within a 5 km radius of the station. Therefore, as indicated by the results of the failure mode and effects analysis (FMEA) model evaluation, the implementation of preventive measures is strongly recommended in order to avoid gas release in settling tanks.

Abstract Pipelines are considered the most practical way to transport oil and gas. However, some factors, such as corrosion and third-party damage, can lead to severe incidents. Appropriate risk assessment can help reduce the risk of pipeline systems. Prioritizing repairs, scheduling physical integrity assessments, and developing emergency plans cannot be adequately done without implementing an appropriate risk assessment method. Risk consists of the probability of failure (PoF) and consequence of failure (CoF) and, in many cases, is obtained from the failure statistics published by the pipeline operators. In an endeavor to apply more engineering concepts to the highly statistics-dominated idea of risk assessment, the PoF can be calculated using finite element and Monte Carlo methods. This paper is specifically concerned with finding the PoF caused by excavations neighboring a buried pipeline, a form of failure rarely considered as most studies about third-party damages are concerned with the direct hit as a failure cause. Hence, a Python script was written that modeled the excavations using Abaqus. The soil was modeled using the Mohr-Coulomb plasticity approach, while the pipe was modeled as a shell. The excavation adjacent to the pipe would cause the pipe to deflect due to gravity. The stress caused by this deflection was compared to the yield stress to determine whether or not it would fail. To determine the probability of failure, this iterative process was carried out for excavations of different sizes using a Monte Carlo method. Additionally, a methodology was implemented to address the issue of computationally expensive models. The method proposed in this paper was compared and weighted against other standard procedures to determine whether the advantages of risk assessment based on finite element analysis (FEA) could justify its complexity.

Abstract The importance of studying Quaternary deposits has increased to such an extent that it now occupies a significant part of research in different parts of the world. In oil-rich countries, including Iran, pollution caused by oil industry activities such as drilling and exploitation has seriously threatened the sediments and soils around these areas. The Abteymour oilfield is one of the big fields in southwestern Iran, located in the area of agricultural lands. As a result, it is essential to evaluate its environmental effects. In this research, 33 surface soil samples were collected, and in addition to measuring the concentration of heavy metals, some physical and chemical characteristics of the soil were measured. Statistical analyses such as correlation coefficient, principal component analysis, and cluster analysis were used to identify the source of pollutants. Environmental geological indices such as geoaccumulation index (Igeo), enrichment factor (EF), contamination factor (Cf), and Nemro integrated pollution index (NIP) were used to determine the level of heavy metal pollution. The cluster analysis results stated that the studied elements were clustered in two groups. Also, the factor analysis results showed that 89% of the variation of the studied parameters was affected by two factors. The results of the statistical analysis demonstrated that the pollution in the region was of anthropogenic origin, and the activities related to the extraction and exploitation of the Abteymour oilfield, agricultural activities, and wastewater impacted the soil quality in the area. Investigation of the pollution level of the samples based on the Igeo, EF, Cf, and NIP indices indicated that the samples were unpolluted for most of the studied elements. Some samples had low pollution levels for elements Na, Mg, Cr, Ni, Sr, Cu, Li, and Pb. Sulfur (S) also included all pollution levels although most of the samples were at the medium level. Based on the modified contamination degree index (mCd) and ecological risk of the sum of elements (RI) indices, 100% of the samples had very low levels and low risk, respectively. Due to the continuation of agricultural activities and oil industries in the studied area, there is a possibility of increasing the level of pollution.

Abstract Oil spill is one of major marine environmental challenges. The main impacts of this phenomenon are preventing light transmission into the deep water and oxygen absorption, which can disturb the photosynthesis process of water plants. In this research, we utilize SpecTIR airborne sensor data to extract and classify oils spill for the Gulf of Mexico Deepwater Horizon (DWH) happened in 2010. For this purpose, by using FLAASH algorithm atmospheric correction is first performed. Then, total 360 spectral bands from 183 to 198 and from 255 to 279 have been excluded by applying the atmospheric correction algorithm due to low signal to noise ratio (SNR). After that, bands 1 to 119 have been eliminated for their irrelevancy to extracting oil spill spectral endmembers. In the next step, by using MATLAB hyperspectral toolbox, six spectral endmembers according to the ratio of oil to water have been extracted. Finally, by using extracted endmembers and SAM classification algorithm, the image has been classified into 6 classes. The classes are 100% oil, 80% oil and 20% water, 60% oil and 40% water, 40% oil and 60% water, 20% oil and 80% water, and 100% water.