Egyptian Journal of Petroleum最新文献

There is a significant need for alternative fuels as a result of increased fuel usage and resource depletion. Esters made from vegetable oils, waste cooking oil and bio alcohols are majorly used in IC engines as a substitute. Coconut oil (Co) and sunflower oil (Su), which have sufficient productivity in India, biodiesel synthesized from karanja oil. In this study, fossil diesel (D) was mixed with karanja biodiesel (B), neat coconut oil and sunflower oil along with ethanol (Et), propanol (Pr) and n-butanol (Bu) alcohols was used. Quinary fuel blends of DB, DBCoSuEt, DBCoSuPr and DBCoSuBu were prepared. The physio-chemical properties of blends were tested and performance and emission tests were carried out on a single cylinder four stroke diesel engine. The results indicate that DBCoSuPr fuel combination increases brake thermal efficiency by 9.2% and DBCoSuEt fuel decreases HC and CO emissions by 37.2% and 53.93% respectively.

Produced fluids from oil field often contain emulsions which are a major challenge in the Petroleum Industry. Emulsion stability determines the ease with which oil and water separate in emulsion and plays an important role for production operations. The standard approach to know emulsion strength involves bottle testing which is time consuming and subject to human interpretation. A faster and safer alternative is by running a mathematical model. However, because of the complexity of emulsion system, an equation from first principles for predicting emulsion stability is not available even with such vast work in the literature. In this research we test a data driven approach for predicting emulsion stability category and introduce a new concept of emulsion stability index. A model is built from the emulsion behavior of real crude oil and validated for field success. A software application of this produced emulsion stability tool, packaged as PrEST, is also created for deploying the model at enterprise level to provide quick guideline for emulsion strength.

To investigate the dielectric strength and mechanical features of modified nitrile butadiene rubber (NBR), titanium dioxide (TiO₂) and magnesium oxide (MgO) nanoparticles have been used. Specimens have been experimentally prepared with loading various concentrations (0.5, 1, 1.5 and 3 parts per hundred part of rubber “Phr”) to NBR base material. The dielectric strength has been evaluated by applying AC high voltage on the prepared samples up to reaching the breakdown state. On the other hand tensile strength, elongation at break and modulus at 100% elongation have been experimented to exploration the mechanical features of the NBR enhanced by nanoparticles. Although all the recorded results of modified NBR samples showed improvement more than the base material at dielectric, tensile strength and modulus at 100% elongation tests. The elongation at break result showed a negative impact; it was caused by forming a new links between NBR and nanoparticles. The dielectric constants of applied nanoparticles are greater than NBR base materials, which can physically explain the improvement in all recorded breakdown results. But the enhancement in the measured mechanical features can be attributed to chemical bonds which were reconstructed and the gaps of NBR base material that had been filled.

Exploitable deposits of barite exist in northeastern Nigeria but are not harnessed because their qualities are not to a standard required for drilling mud formulation. The work presented here is a preliminary result obtained from the beneficiation of barite samples from these deposits with the aim of attaining a level that can be used in drilling mud formulation. Results of elemental, mineralogical, and mud densities, cation exchange capacity (CEC), and filtration loss were obtained using Instrumental Neutron Activation Analysis (INAA), X-Ray Diffraction (XRD), and other API 13B-1 recommended measurements before and after beneficiation. Barium composition of raw and laboratory-treated samples (GMB, IBI, BOK, DUM, and GAM) in percentage (%) are 50.5 ± 0.2, 55.6 ± 0.2, 57.9 ± 0.2, 57.6 ± 0.2, 0.097 ± 0.004, and 54.6 ± 0.2, 58.3 ± 0.2, 56.3 ± 0.2, 52.4 ± 0.2, 0.0845 ± 0.007, respectively while major impurity (Fe) is highest (1.52 ± 0.01) in sample GAM and lowest (0.025 ± 0.002) in sample DUM. The densities (g/m³) obtained after preliminary beneficiation increased to 3.89, 3.39, 4.28, 4.32, and 2.56 for samples GMB, IBI, BOK, DUM, and GAM, respectively. Filtration loss of 5 % W/V barite-mud formulation reported 12.2 ± 1.4 and 4.95 ± 1.7% more loss than two API-13A grade barite. The filtration loss reverses at 10 % W/V barite-mud formulation, with test barite reporting on average 3.22 and 1.15% improved filtration control against the API-13A barites. Mud formulation with loss additives reported significant filtration control with 23.6, 23.6 and 8.54% improvement over API 13A grade for beneficiated BOK, DUM and IBI samples. Similarly, the same formulated samples reported identical CEC values against API-Helicon and improved values against API-1 at 4.67, 7.29 and 4.67% respectively. Even at this stage BOK, DUM and IBI were improved to level that can be used in drilling mud formulation with samples DUM and BOK having the best potential (low impurity and high density). These results show that barite deposits from north-eastern Nigeria have great economic potential.

Cocogem surfactants are synthesized based on the neutralization reaction of higher monocarboxylic acids (octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid) and 2:1 mol of N,N'-bis(propyl-2-ol)ethylenediamine). Krafft temperatures of these surfactants and colloidal chemical properties of their aqueous solutions were determined by using tensiometric and conductometric measurements. Surface activity parameters of cocogem surfactants, critical micelle concentration (CMC), counter-ion binding degree (β), the surface tension reduction effectiveness (π_CMC), excess concentration of surface (Γ_max), as well as area per molecule at the interface (A_min), Gibbs free energy (ΔG_ad and ΔG_mic) values of adsorption and micellar formation processes are calculated. The size of the aggregates formed by anionic cocogem surfactants in an aqueous solution was determined by the DLS method. It was defined that cocogem surfactants have antibacterial properties against SRB, which is considered to be the most dangerous for the oil industry.

Background

this paper reviews the results obtained from recent studies mentioning the crustal architecture in Cameroon. It also discusses the study of [1] “Estimation of Curie depth, geothermal gradient and near-surface heat flow from spectral analysis of aeromagnetic data in the Loum-Minta area (Centre-East Cameroon)”. The paper published by [1] is an application of the spectral method for the determination of Curie depths, followed by interpretations on the local thermal structure (thermal gradient, heat flux) of the crust. However, some outliers are remarkable and depend at first analysis on a bad mesh of the data following a windows of 27.75 * 27.75 km. Similarly, the failure to take into account the various parameters (seismic, geological, tectonic) which would help to better calibrate the results.

Discussion

with this communication, we would like to mention and clarify some errors in the paper published by [1] based on a global review of thermal behaviour of the crust.

Summary

It is strongly recommended that information on regional geology and seismicity be used to estimate the Curie depths and that other independent data be integrated to determine the thermal and mechanical behaviour of the crust in Cameroon.

Unstable market of conventional fuel resources with the high fluctuation of oil prices is shifting interest towards obtaining fuels from renewable components. Unsaturated aliphatic hydrocarbons, produced in oil refineries and from renewable bioresources, present a potential feedstock for the production of oxygen-containing additives for motor fuels. In the present paper the interaction of the simplest representative of diene series – isoprene with various classes of oxygen-containing compounds: ethyl alcohol, acetic acid, acetaldehyde, produced from biomass as well, is analyzed. The possibility of synthesizing of various acetals and paraldehyde, proposed as potential high-quality fuel additives, via interaction of isoprene with ethyl alcohol and acetaldehyde, is shown. Within the first series of experiments, sufficiently high yields of products are obtained. Yield of potential oxygen containing additives to gasoline produced via interaction of isoprene with ethanol exceeds 15 %, via interaction of isoprene with acetaldehyde: potential diesel additives −40 %, gasoline additives −12.9 %.

A marine geophysical survey was carried out over the ruins of the ancient Eunostos harbor, in front of the recent western harbor of Alexandria. The survey works aimed to study the seafloor and the subsurface layers over the survey area using side-scan sonar and sub-bottom profiler. It is attempted to identify the impact of nature and geo-hazards on the coast of the submerged ancient harbor. Numerous ridges, reefs and breakwaters which protected the port from the northern swells were detected on the acoustic images of the side-scan sonar. In addition to some undefined artifacts and ancient coastal scars were noticed across the seafloor. Seismic interpretations also showed series of shallow diffractions that generally intensified towards east and north. Also deformed and disturbed subsurface layers were noticed beneath the area of the submerged ancient harbor. Side-scan sonar and sub-bottom profiler findings are concordant with the descriptions of the ancient literature and succeeded to confirm the vulnerability of the ancient coastal harbor to natural disasters during the past times.

The cost of oil and gas drilling fluids with their chemical additives is fairly high above the total well cost. It is imperative that mud engineers find cellulose-rich agro wastes local alternatives to cut down costs. In this work, we analyzed the effect of pineapple leaves as a cheaper and more environmentally friendly alternative additive on certain drilling fluid properties. Laboratory analysis and Factorial Design of Experiment (FDE) were carried out to study the effect of Pineapple leaves (PL) on water-based drilling mud’s viscosity and fluid loss at an ambient temperature of 29 °C, and pressure of 100 psi. Full 2³ and 2⁴ FDE which consider aging; the concentrations of Carboxymethyl cellulose (CMC) and PL; fluid loss time are independent variables while viscosity and fluid loss are the response variables that were managed. The main and interaction effects were investigated. Results showed that pineapple leaves are slightly acidic and cannot completely replace CMC. Combining it with CMC yields a better viscosity and fluid loss property. 1 g of CMC combined with 10 g of PL in a barrel of drilling mud gave a filtrate volume slightly higher (9%) than the control mud with 2 g CMC only, whereas, combining 5 g/10 g of PL with 2 g CMC reduced the filtrate volume by 5 and 24 %, respectively, making PL a good complementary fluid loss agent. Analysis of the main and interaction effects from factorial design also revealed that the PL and its interaction with CMC contribute about 30% to viscosity and prevented fluid loss by 5%. A plot of the plastic viscosity and fluid loss volume of samples containing 10 g of PL and varying CMC concentrations showed that combining the two additives in a CMC to PL ratio of 1.5:10 yielded mud properties comparable with the control mud. The volume of PL agro-wastes was also reduced.

Owing to strict emission-policies, vehicle manufacturers are mandated to control hazardous emissions from diesel engines. One novel step adopted in this work, is the use of hydrogen enrichment with nanofuel, where TiO₂ nanoparticles- Afzelia Africana biodiesel-mix was blended with hydrogen for use in a diesel engine. 25 ppm TiO₂ nanoparticles were admixed with biodiesel and ultrasonicated. Thereafter, H₂ was introduced through the air inlet at the lowest possible flow rate (3–4 LPM) to avoid reaching H₂/air explosion limit. The ratio of H₂ to the blended fuels (BNH) is (15: 85 vol/vol %). The effects of the nanofuels blended with pure H₂ were investigated by evaluating the brake thermal efficiency (BTE), wall temperature of the combustion chamber, NO_x, CO, and HC emissions. Via a simplified model, the associated uncertainties in the parametric variations were determined while a Supervisory Computer Aided Data Acquisition (SCADA) system with an in-built program, was configured in the engine set-up for data generation. The results showed that higher BTE of the blends + 25 ppm TiO₂ alongside hydrogen flowrates of 3 LPM and 4 LPM helped to improve the engine performance with lesser emissions of CO, NO_x and HC respectively. Sample BNH@-3-LPM gave the best performance/BTE of 39.5 % compared to BNH@-4-LPM (32.4 %), BN (29 %) and diesel (29.4 %), whereas, BNH@-3-LPM gave the lowest emissions of 0.4, 5 and 81 g/kwh for CO, HC and NO_x respectively compared with diesel which gave corresponding emissions of 0.8, 35 and 200 g/kwh for CO, HC and NO_x respectively.