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Welcome to UISpace, The University of Ibadan Institutional Repository. A collection of theses, articles, books, videos, images, lectures, papers, data sets and all types of digital content originating from the University of Ibadan Nigeria. This repository is managed by the Kenneth Dike Library University of Ibadan, Nigeria.
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Comparative analysis of the effect of plant-based and petroleum-based wax inhibition additives on heavy crude oil in the Niger-Delta
(Egyptian Petroleum Research Institute, 2025) Magashi, T.; Akintola, S.A.; Ebere, F.O.; Magashi, L.N.; Fulalo, L.D.
This study investigates the use of plant-based oils-soybean oil (SO), coconut oil (CO), and their biofuels, and petroleum distillates, namely automotive gas oil (AGO) and premium motor spirit (PMS) as potential wax inhibitors. At various volume concentrations (3 %, 5 %, 10 %), the impact of the additives on the pour point, rheology, and wax deposition of a heavy waxy crude oil sample from the Niger-Delta was investigated. The ASTM standard test procedures were used, using the cold finger apparatus for wax deposition test and paraffin inhibition efficiency determination. It was observed that though all the additives tested could reduce crude oil viscosity, SO and CO had the least effect compared with their biofuels and petroleum distillates (which had the greatest effect). PMS reduced the yield point (YP) significantly at all concentrations, while AGO reduced it only at a low concentration (3 %). The plant oils and biodieselts had a poor effect on YP. Again PMS had the most effect on pour point reduction, followed by AGO. SO and SO biodiesel (SOBD) showed a similar trend, raising the pour point at low concentrations, while reducing the same at higher concentrations. CO and COBD both reduced the pour point at all concentrations. The cold finger wax deposition test ultimately revealed that SO is a good wax crystal modifier. At a high concentration, its paraffin inhibition efficiency is almost comparable to that of AGO and PMS at reduced concentration. Its flow improvement property is however relatively poor, as it could not improve the YP and pour point of the crude oil significantly. In comparison with CO, however, SO shows greater potential for wax inhibition and flow improvement, while AGO and PMS show excellent results. The plant oil biodiesels (SOBD and COBD), however, showed more promise than the original plant oils (SO and CO) in flow improvement, but are less attractive in wax inhibition.
Advancing sustainability of drilling fluid: coconut and shea butter oils as alternative to diesel
(Sciencedomain International, 2024) Akintola, S.A.; Ehwarieme, F.; Amaechi, I.
Drilling fluid is a key element in the drilling process because it lifts cuttings to the surface, maintains a stable wellbore, and generates sufficient hydrostatic pressure to prevent the influx of formation fluids into the wellbore. While oil-based drilling fluids offer advantages like wellbore stability, lubrication, and temperature resistance, disposing of oil-contaminated cuttings, particularly those using diesel, harms the environment. This study explores the use of coconut oil and shear butter oil, a renewable and biodegradable resource, as the base for oil-based drilling fluids. Two samples of coconut oil and shea butter oil-based mud samples were formulated and tested in the laboratory against the conventional crude oil-based mud. Laboratory tests compared each sample of coconut oil and shea butter oil-based mud against conventional diesel-based mud. Tests included FTIR characterization of additives, and evaluation of gel strengths, yield point, viscosity, and emulsion stability at 120°F and 300°F. Filtration loss and mud thickness were also measured. Results indicate that coconut oil and shea butter oil-based drilling fluids offer promising rheological properties and environmental benefits. Coconut oil-based sample (VCO I) exhibited superior viscosity and emulsion stability, though it produced a thicker mud cake, indicating a need for optimization. These alternatives present a viable solution to reduce the environmental impact of drilling operations. Further research and field trials are recommended for practical application.
Sterilized chicken feather as eco-friendly corrosion inhibitor for mild steel in a water-based drilling mud–gravimetric and FTIR assessment
(Sciencedomain International, 2024) Akintola, S.A.; Aleem, A.A.; Oki, M.; Ikubanni, P.P.; Adediran, A.A.; Esabunor, O.R.
This research evaluated the corrosion performance of mild steel in sterilized and unsterilized alkaline mud corroding systems using chicken feather powder (CFP) obtained through the usual hydrolysis and acid neutralization protocol. Insightfully, gravimetric analysis revealed that bacterial infestation of the unsterilized environment caused its corrosion performance to be lower at 10.3% while the sterilized counterpart stood at 49% at 92 days of exposure to the environments respectively. The functional groups, C=N, O=C=O, H-C=O etc, revealed by FTIR to be present in the protein saturated feather were overwhelmed by microbial activities rendering them inactive to perform as inhibitors.
Performance Evaluation of Delonix regia sawdust as cement retarder in oil and gas well
(SCIENCEDOMAIN international, 2024) Akintola, S.A.; Kolajo, T.; Obande, A.
Sawdust, a byproduct of wood exploitation and processing, poses environmental pollution risks if not managed appropriately. Its substantial carbon footprint can lead to pollution, habitat disruption, and fire hazards. However, repurposing sawdust as a chemical additive in cement slurry within the oil and gas industry offers an environmentally friendly solution. This practice aligns with sustainability goals, enhances cement slurry properties, promotes wellbore stability, and replaces more hazardous additives, thereby reducing environmental impact. This study is aimed at the production of a retarder (sodium lignin) from sawdust waste obtained from the Delonix regia species, and examining its effect on the thickening time/consistency, compressive strength, and rheological properties on the slurry of a Class G cement At a Bottom Hole Circulating Temperature (BHCT) of 90°C, thickening time tests conducted on the slurry samples revealed that as the concentration of the locally synthesized retarder increases, the thickening time of the concrete also increases, with minimal effect on compressive strength. The optimal thickening time result of 6 hours and 13 minutes was achieved with 0.5% Sodium Lignin (Retarder from Delonix regia sawdust) replacing a portion of the cement. At a bottomhole static temperature (BHST) of 100°C, increasing the concentration of the formulated sample led to higher Plastic Viscosities (PV) and yield points in the slurries. The findings indicate that slurries formulated with sodium lignin maintain viscosities within recommended values, making them suitable for pumping.
Performance evaluation and application of apparent viscosity models based on marsh funnel viscosity and mud density using high-temperature high-pressure field data
(Melbourne Scientific Publishers, 2024) Ekanem, P.E.; Akintola, S.A.
The exponential increase in global demand for energy has necessitated increased oil and gas operations in harsh terrains. This in turn requires high-level precision in operations as errors may lead to great implications on cost and resources. Drilling fluid plays a key role in the success of every oil and gas drilling operation. Therefore, monitoring and engineering of drilling fluid in real time to ensure its sustained suitability as it goes through different formations and conditions remain a priority. Different mathematical models have been researched to complement this effort. However, practical application of these models has not been addressed, creating a gap between theoretical solutions and practical applications. Field data from five different wells were used to evaluate the performance of five models in predicting the apparent viscosity of drilling fluids based on marsh funnel and mud density test results. The best prediction had root mean square errors of 2.57; R-squared of 0.71; mean absolute percentage error of 5%; and mean absolute error of 2.16. It was found that mathematical models could be used to predict apparent viscosity with high accuracy and that the models could be used to identify regions of concern during the drilling process by a simple history matching and comparing of the performance of the models on previous data using a particular model and comparing the result with results from other models to observe patterns. This work, for the first time, gives a practical application of mathematical models based on marsh funnel and mud density tests.