Journal of Petroleum Research & Studies

The effect of paraformaldehyde in the solution of 15% HCL as an inhibitor of C-steel corrosion has been studied using the weight loss method. It was found that the efficiency of inhibitor increased by increasing the inhibitor concentration and decreasing temperatures. Also, the action of paraformaldehyde as a corrosion inhibitor has been attributed to the insoluble complexes was adsorbed on the C-steel surface. The iron complexes were identified by FTIR spectrum and the mechanism of inhibition was explained as Langmuir adsorption. The thermodynamic parameters of the adsorption process were calculated and explained.

Scale formation and corrosion phenomena are major technical problems at Basra Refinery/ South Refineries Company (SRC). These technical problems are concentrated in cooling towers which are used to supply cooling water to the processing units. The Scales and corrosion products precipitate inside cooling units, heat exchangers and pipeline networks affecting negatively efficiency of refinery’s equipment. In this work, a real plant data was collected from four cooling towers which is supplied the coolant to the crude distillation units of the refinery and also from the raw water supplier. The collected data was fitted by Langelier model to predict the tendency of cooling water for scale forming and activation of corrosion. The obtained result shows that the cooling water has a tendency to form scale (CaCO3 Precipitation) at cooling tower units. Also the feed water has the same tendency for scale forming.
After analyzing the LSI (Langelier Saturation Index) results, the research team recommends the particular company to overcome this problem by installing a Reverse Osmosis (RO) plant for treating raw water to decrease the concentrations of total dissolved solids (TDS) which result scale and corrosion in the parts of cooling tower as an option to solve the problem.

The reinforced fiberglass in cement slurry reflects the effect on its properties compared to usual additives. Fiberglass is typically used in cement slurry design for one or another of the following goals: (Earth earthquake, bearing storage, and with differential stresses, to enhance cement durability and increase its compressive strength). The main goal is to use glass fiber and ground fiberglass to improve the tensile strength and moderate compressive strength significantly. On the other hand, the use of glass fibers led to a slight increase in the value of thickening time, which is a desirable effect. Eleven glass fiber samples and milled glass fiber were used to show these materials' effect on Iraqi cement with (0.125, 0.25, 0.5, 0.75, 1, and 2) % of cement weight. Those tests used to study cement slurry’s following properties were compressive strength, thickening time, rheology properties of free water, filtering, and density. These evaluations showed that slurries with less than 1% fiber content gave a higher compressive strength than a sample containing more than 1% glass fiber. However, the slurry mixed with equal or less than 1% milled glass fiber is higher compressive than the sample mixed with more than 1% milled glass fiber. So the optimal concentration for glass fiber is less than 1% by weight of cement (BWOC); either for milled glass fiber, it is less or equal to 1% BWOC. Both materials contributed to increasing the compressive strength of the cement. However, attention must be paid to the ideal concentration that should be added during the cement slurry preparation because if we use these two materials carelessly for the ideal concentration, this leads to the collapse and bombardment of the resistance of the cement rock. In other words, the collapse of cement resistance and causing problems during the cementing process.

This study presents is a classification of reservoir properties (porosity and shale volume) into rock types for carbonate Rumaila reservoir in Central Iraq (Ahdeb Field). The Cluster analysis method is used to identify rock types and to recognize well log clusters of similar characteristics. For most subsurface research, the determination of the rock type (lithofacies and petrofacies) is not adequate enough because of a lack of cores and cuttings. An interactive petrophysics software program was used to get the results of a cluster analysis technique, in order to determine the rock typing (log facies) in Rumaila formation units in the Ahdeb oil field. Initially, petrophysical parameters such as porosity, shale volume and quantity of various reservoir minerals were determined using the probabilistic evaluation process. In the second stage, the multi-resolution graphic clustering method was employed to separate the sequential electrofacies which resulted in the identification of four electrofacies with different geological reservoir properties. The vertical variations of the rock type for Rumaila formation are based on four log facial groups. These log groups are categorized according to porosity and shale volume of formation based on responses to well logs after division of Rumaila formation into four units (Ru-1, Ru-2, Ru-3, and Ru-4).A 3D rock type model for Rumaila Formation was performed using Petrel software in order to illustrate the horizontal distribution of rock type along the Ahdeb field and showing the best characterized of reservoir rock type in any unit of Rumaila Formation. Cluster analysis technique classified porosity and shale volume, which were calculated for Rumaila Formation using well logs, into four similar characteristics rock types: rock type-1, rock type-2, rock type-3 and rock type-4. A 3D Petrel model of rock type shows that rock type-2 has better reservoir quality than other rock types in Rumaila Formation which is characterized by high porosity and low shale volume. The model clarifies the distribution of rock type-2 in the Ahdeb field at units Ru-1 and Ru-3 of Rumaila Formation.

The Ismail-1 is located northwest of the Bai Hassan Field (Daoud Culmination), within the administrative boundaries of the provinces of Kirkuk and Erbil, which was later named Ismail Field. The objective of the research is to determine the geological relationship (structural and reservoir) of the well Ismail-1 with the Bai Hassan Field (Daoud Culmination). Based on geological and reservoir studies and seismic surveys of the region, the first basis of the research was based on the stratigraphy, structural, reservoir and morph structure aspects of this relationship.
In the beginning, the serial sequence of the well was reviewed and compared with David's wells. Then, cross-sections and long sections were drawn through the wells of Ismail-1 and Daoud wells, as well as, the fluid levels dotted on such sections. After that, a structural contour map was drawn on top of Jeribe Formation for the area of well Ismail-1 which is currently known as Ismail Field and part of the Bai Hassan Field (Daoud Culmination), depending on the structural and reservoir data. It was found that the area of the well Ismail-1 is an asymmetrical convex fold, the southwestern flank is more inclined than the northeastern flank, and the Daoud Culmination and the Ismail fold is separated by a narrow saddle. However, depending on the structural contour map of the top of Jeribe Formation (-1325) meters from the mean sea level, the deeper levels of which surround the two Culminations together, the similarity of the reservoir properties and the different levels of fluid in the Daoud Culmination and the area of the Ismail-1, all confirm that they are two separate Culminations of one field. So the so-called Ismail Field can be considered a third Culmination called Ismail Culmination of the Bai Hassan Field.
Using topographical maps and satellites data, the morph structure and geomorphological phenomena of the northwestern extensions of the Bai Hassan Field (the area of well Ismail-1) and towards the Quir Field, were studied and the northwestern aerial extensions of about 18 km length and 5 km width were delineated.
Thus, the Bai Hassan Field is consisting of three Culminations (from the southeast to the northwest, Kithka, Daoud and Ismail Culminations) with a total length about 50 km.

The current study is giving a new, more realistic mathematical description of the effect of stress on the amount of porosity and permeability. In addition to that it can be used to find mathematical formulas for other petrophysical characteristics, and to find mathematical relationships between new variables such as porosity and permeability in terms of depth or between porosity and permeability itself.
The measurement of the porosity and permeability property of reservoir rocks (Core) is important in terms of reservoir studies, as they enter into petrophysical calculations such as water and oil saturation as well as calculating the amount of hydrocarbon reserves and thus give a clear picture of the productivity of the reservoir oil. One of the most important factors that affect the amount of porosity and permeability is the so-called over burden pressure, where the reservoir rocks are under the influence of great pressure resulting from the weight of the ground layers, so when core samples are extracted from the reservoir they will expand as a result of the disappearance of the layer pressure on them, which leads to a change in the amount of porosity and permeability, Thus, laboratory results will be different from the real porosity and permeability of the reservoir, which leads to errors in reservoir calculations.
The simple non-linear regression method was used to formulate several models belonging to four families of mathematical functions (exponential function, forces function, logarithm function and polynomial function), which describe the relationship between stratified pressure and both porosity and permeability
The stable state equation (SSE) was chosen as an optimal mathematical model describing the relationship between over burden pressure and both porosity and permeability. The model's performance was evaluated using the determination coefficient (R2), as the results were highly accurate and reliable.
The study concluded that the mathematical model can be applied as a good tool in estimating the effect of over burden pressure on the petrophysical properties of sandstones rocks.

In the present study, the new oils were produced that compete with global oils, which reflects a positive economic return for the Middle Refineries Company and the reduction of imported oils in support of the national economy and the Iraqi product protection law with clarification of some basic terms and concepts for the production of ready-made oils, which enables knowledge of the main points of evaluating oils.
As well as addressing the types of base oils from which ready-made oils are manufactured, the way to obtain base oils of different levels, and the production units.
The reliance on research methods was on comparison with imported and manufactured oils according to international certificates and in coordination with the Research and Quality Control Department.
Laboratory experiments were conducted with different proportions for mixing until the required results were reached and using laboratory devices to conduct the required tests to meet the international standards.
Where several experiments were conducted by changing the mixing ratios between base oils (SN-150, SN-500). In addition, changing the percentage of additives of viscosity enhancer (VI) as well as changing the degree of pouring improver (PPD) while keeping the ratio of the improver constant (MX-2171). Which is wt. 13.6%.
Final results were obtained for mixing ratios to obtain identical specifications for diesel engine oil in conformity with international specifications, where the ratio of the MX-5217 enhancer was around 13.6%, which is considered the main enhancer as well as the viscosity enhancer, the ratio was 3.0% and the spillage reduction ratio was 1.5%. For a mixture of base oils, it was for the base oil SN-150 up to 18.0% and for base oil SN-500, the percentage was 36.9% knowing that all the aforementioned percentages are weight ratios.

The study aims at investigating the volatility of crude oil prices in the global market for the period (1990 - 2017). It also aims at estimating the returns of the global oil market and the risks that it faces as a result of volatility in the price of crude oil by using GARCH Models. The study revealed that the average return of volatility of Brent crude prices in the global market is about (1.12%) per month as well as the presence of a risk ratio in the global oil market of about (%0.32).