Journal of Petroleum Research & Studies

Hartha Formation (Upper Companian-Mastrechtian Sequence) consists mainly of detrital organic limestone and dolomitic limestone and may contains streaks of marl and through the petrographic study of the rocks of the formation, it was found that it consists of skeletal granules consisting of benthic foraminifera represented by fossils (orbitoid, rotalide and miliolide) and a few planktonic foraminifera belonging to the family of Globigerinacea and red, green algae, echinoderms, mollusks and the Formation also contained a few Calcispheres and these granules appeared affected by several modifying processes, the most important of which are Dolomitization, recrystallization, dissolution, Micritization and chemical compression and it was found through the analysis of the Microfacie that the Formation consists of four main, microfascies the upper limit of the Formation is conformable with the Formation of the Shiranish, while the lower limit represents unconformable with the Formation of Mashura. The present study focused on the effect of Diagenesis processes on the Hartha Formation in four subsurface sections within the Balad field in Salah al-Din Governorate in central Iraq, representing the first section (Ba-1) with a thickness of (443) m, the second section (Ba-5) with a thickness of (306) m, the third section (Ba-7) with a thickness of (306) m. (Ba-9) and thickness (307) m. Where (355) slides consisting of rock cutting and cores were studied, (144) slides for the well (Ba-1), (58) slides for the well (Ba-5), (54) slides for the well (Ba-7) and in the well (Ba-9). It was by (99) slides, as well as the logs of the above wells, through which the Formation was divided into three porous units.

The structural and seismic properties of the Paleocene carbonate reservoir are re-evaluated, using 3D seismic data multi-attributes, to improve reservoir prediction accuracy rarely documented earlier. This study highlights a number of relevant post-stack seismic attributes for understanding the structural setup and seismic properties of a carbonate reservoir. The structural analysis was carried out using seismic interpretation, combined with multi-attribute analysis for prospect actualization and generation of a 3D structural model to determine the structural aspect. The structural interpretation reveals the presence of faults and an asymmetrical anticlinal structure demonstrating a four-way closure, confirming compressional tectonics. The high amplitude anomaly (-6 to 12) combined with the RMS attribute (23 to 32) suggests bright spots in the Paleocene carbonate reservoir and gas saturated zone, the variance attribute (0.05 to 0.03) highlights the presence of two major faults, and the lower instantaneous frequency demonstrates the presence of hydrocarbons. The attribute results indicate that the Lockhart Limestone possesses good reservoir potential as revealed by DHI (bright spot), gas saturated zone and a trapping mechanism supported by four-way structure closure in the region and can help to understand analogous carbonate reservoirs in similar geological settings around the world.

This study aims to investigate the properties of drilling fluids with low solids content prepared using Iraqi bentonite. Polyacrylamide polymer, sodium polyacrylate polymer, Nano silica, and fine silica were used, as the results demonstrated the success of these materials in preparing drilling fluids with low solids content. As for micro silica, it is a material used with cement, but it was used in this study with drilling fluids because it is cheap in addition to being an environmentally friendly material. Polyacrylamide is a highly absorbent and effective material, which is usually used during well injection, but in this study it was used to improve the properties of Iraqi bentonite. 10 samples of drilling mud were prepared using the aforementioned materials in different proportions, and Iraqi bentonite was also used as a dispersant or dispersant phase. The percentage of bentonite during preparation ranged between (1.5-5) % in order to achieve sufficient gel resistance and balance the filtration speed. By drawing the relationship between shear stress and shear rate, it was found that all prepared samples follow the power law model, as this was used in hydraulic calculations in order to determine the pressure loss in the hydraulic system of the well. The results show that polyacrylamide polymer has the best effect on Iraqi bentonite among the other used materials in this study, where 1% from this material is enough to enhance properties (rheology and filtration) of Iraq bentonite. However, it has been observed from the laboratory results that when the percentage of bentonite is reduced to 1.5%, the prepared liquid will fail to suspend the barite and therefore will not achieve the required density in spite of the addition of barite. The best sample for the drilling fluid is when the percentage of the total solid is 5%, i.e. (10 gm Iraqi bentonite, 7 gm barite, 1 gm polymeric, Nano, or nanomaterials). As this drilling fluid had the best performance in terms of pressure loss, as they gave the least pressure loss.

Permeability estimation is a vital step in reservoir engineering due to its effect on reservoir's characterization, planning for perforations, and economic efficiency of the reservoirs. The core and well-logging data are the main sources of permeability measuring and calculating respectively. There are multiple methods to predict permeability such as classic, empirical, and geostatistical methods. In this research, two statistical approaches have been applied and compared for permeability prediction: Multiple Linear Regression and Random Forest, given the (M) reservoir interval in the (BH) Oil Field in the northern part of Iraq. The dataset was separated into two subsets: Training and Testing in order to cross-validate the accuracy and the performance of the algorithms. The random forest algorithm was the most accurate method leading to lowest Root Mean Square Prediction Error (RMSPE) and highest Adjusted R-Square than multiple linear regression algorithm for both training and testing subset respectively. Thus, random Forest algorithm is more trustable in permeability prediction in non-cored intervals and its distribution in the geological model.

Two wells are selected in the Faihaa field (well-1 and well-2) to study the petrophysical properties and evaluate the reservoir units of the Mishrif Formation. The cross plots of density-neutron and M-N show that the Mishrif Formation consisting mainly of limestone with calcite as the main mineral with the presence of dolomite in very few percentages and points within the range of secondary porosity and gas. Petrophysical properties were determined and plotted as computer processing interpretation (CPI) such as shale volume, porosity, water saturation, and hydrocarbon saturation by using Techlog software and showing that well-2 has a good petrophysical property than well-1. The main reservoir units in both wells are MA, MB, MC, MD and ME. The MD unit considered as the best reservoir unit with good of reservoir quality compared to the rest of the units due to good porosity values and low values of shale volume and water saturation. each of the MB and MC units has a good reservoir quality in well-2 and the lowest reservoir quality in well-1, while both the MA and ME units consider the weakest units that have poor reservoir quality, especially the MA unit which has a few thicknesses with high shale volume values.

Gaseous hydrates are defined as (clathrates) consisting of three basic components (crude liquid, gas, and water). When the gas (guest) is liberated from the raw liquid by the concepts of dynamic and thermal movement of gas and liquid, the (gas) is confined inside the cage of the evaporating water bubble (the host) to form gaseous hyder due to the conditions of heat and pressure in the form of a spherical crystalline structure linked by hydrogen bonds under the van der Waals force effect. Hydrates, when they occur, cause total or partial blockage and obstruction of the flow of crude oil and loss of operational capacity. It depends on the type of gaseous hydrate formed and the nature of the local conditions. Therefore, gaseous hydrates are considered one of the most important local scientific problems that crude oil refineries suffer from, especially in the two locations, starting from the primary heating area - heat exchangers package (EX-211ABC) all the way to the heating area Secondary - (the unit's furnace). The present study discusses in detail the.
most important scientific and practical solutions, and through the results it was found that the technical practical steps adopted by the operators of the refining units cause future damage and reduce the design life of the unit, in contrast to the scientific solutions.
The paper discusses the most important issues and related analyzes that predict the occurrence of hydrates to reduce or limit the impact of the occurrence of gaseous hydrates by relying on the following checks (Rvp, salt content, sediment and water). In short, the aim of this paper is to identify behaviors and discuss problems and solutions gas hydrates in crude oil refineries (Najaf Refinery - unit 2) specifically in the second heating area (Branch-B 105 thermal unit furnace), the paper shows complete information in a concise form for operators and engineers of the crude oil refining sector.

Engine oil (EO) is produced by mixing base oil derivatives from crude oil with chemical additives to the lubricity of moving parts and reduce the friction inside the engine. Used lubricating oil (ULO) is one of the hazardous materials that consists of pollution harmful to the environment, it needs to be managed properly. In this work, vacuum distillation technique is used to recycle used lubricating oil. Used lubricating oil samples from two different brands of diesel engine oil (20w-50) and gasoline engine oil (10W-30) are used in this study. Various properties of ULO and recycled oil were characterized such as kinematic viscosity, viscosity index, density, pour point, flash point, Sulphur content, and Fourier transform Infrared spectroscopy FTIR. The yield recycles for ULO of gasoline engines, diesel engines, and mix (gasoline and diesel) by vacuum process were 85%, 74%, and 75% respectively, it was discovered that the sulfur component decreased from 9792.3 ppm of ULO to 405 ppm of yield distillates. The pour point results show an increase from -30 °C of used lubricating oil to -18 and -6 for distillates cut for vacuum distillation, compared to the pour point of Iraqi base oil 40 and 60 Stook (SN150 and SN200) -18 °C and -6 °C.

In this research work, the main distillation column of Salahadin 1 refinery in Baiji Refineries is simulated and analyzed using Aspen HYSYS. Kirkuk, Basrah and Ajeel crudes are mixed together (with unknown mixing ratio) to create the feed stream of this unit. The determination of the blending ratio of these streams beside performance analysis of the system using actual plant data to increase the operating capacity are the main objectives of this research work. So, this work is very helpful to the refinery because it can be applicable to manage these blending ratios to obtain desired product quality. Also, this work enables the CDU unit at the refinery to work at full capacity. The validation results show that the system is perfectly simulated with Aspen HYSYS and the mixing ratio of (Ajeel, Basrah, and Kirkuk) crudes are (0.102,0.5, and 0.398) respectively; Furthermore, this study suggested that, it is important to replace the transfer line pipe diameter between the furnace and the distillation column according to the design specifications which enables the operators to rise the feed volumetric flowrate into full capacity.

Annually, a high amount of hazardous oily sludge (OS) is produced by North Refineries Company (NRC) Baiji. This work aims to study the specifications of oily sludge in crude oil storage tanks and to convert it into activated carbon (AC) by pyrolysis using KOH activated agent. The physical properties of OS have been measured and analyzed. The AC is produced by carbonizing oily sludge to char under N2 flow using KOH at an impregnation ratio of 2:1 KOH/char. The pore structure, morphology of the surface, and surface chemistry of the AC produced were characterized using Brunauer-Emmet-Teller (BET), Fourier Electron Scanning Electron Microscopy (FESEM), and Fourier-Transform Infrared Spectroscopy (FTIR). The result shows the surface area of the produced AC was 350 m2/g with a mesoporous structure. Based on the findings, the obtained surface area of the AC indicates the oily sludge was a light precursor, which is helpful in producing gas and liquid fuels rather than solid fuel.

Microscopic organisms are the only single-celled organisms proposed for the advancement of techniques for Estimation of Oil Recovery (EOR) because they have numerous desirable properties, including a simple structure and an unsustainable growth rate when supplied with vital nutrients, resulting in the release of metabolic chemicals like Aerosols, acids, minimum lubricants, surfactants, and polymers.
Clostridium acetobutylicum was isolated from intensive rice cultivation soil and has the ability to use polysaccharides such as starch and carboxylmethyl cellulose to produce biobutanol, while Desulfovibrio hydrocarbonoclasticus was isolated from marine sediment in Iraq and grows in anaerobic synthetic seawater medium with the addition of a trace element solution. These bacteria can also withstand difficult conditions High salinity, high pressure, and high temperature play roles and contribute to underground geological formations. An aqueous mixture of nutrients, Clostridium acetobutylicum, Desulfovibrio hydrocarbonoclasticus, and molasses with nutrient and bacterial spore injection into a reservoir. As a result, these microorganisms are capable of considerable catalytic reactions.
production of a diverse spectrum of products (biosolvents, bioacids, biogases, and biosurfactants) from relatively simple nutritional compounds, multiply vigorously under favourable conditions, and have resulted in increased oil release from reservoir rock. The well began producing 70 days after the medication was started. 80 to 90 days after the injection began, relatively brief polyunsaturated fats, Carbon dioxide, and residues of ethanol, 1-butanol, and acetone were detected. Because of their highly resistant endospores, Clostridium are the most ideal of the several microbes used in MEOR (Microbial enhanced oil recovery). Desulfovibrio strains capable of producing biosurfactants in situ, which are beneficial to the MEOR process, are also valuable. Nutrients are often supplied as fermentable carbs to promote microbial metabolism.