DEPARTMENT OF PETROLEUM ENGINEERING

Efficient management of oil reservoirs requires accurate prediction of reservoir performance and optimization of recovery strategies. This study focuses on the simulation and performance analysis of a waterflooded oil field using Computer Modelling Group (CMG) software. Waterflooding, a secondary recovery method, is applied to sustain reservoir pressure and enhance oil displacement efficiency after primary depletion. In this research, a threedimensional reservoir model was constructed using geological, petrophysical, and production data, incorporating rock and fluid properties such as porosity, permeability, viscosity, and relative permeability curves. The simulation was performed using CMG IMEX, a black-oil simulator, to evaluate reservoir behavior under both natural depletion and water injection scenarios. The results from the base case simulation indicated a gradual decline in oil production rate due to reservoir pressure depletion, while the waterflooded case demonstrated a significant improvement in oil recovery performance. The initial oil production rate before flooding was approximately 1500 STB/day, which declined to 500 STB/day before water injection. After waterflood initiation, oil production increased to about 1450 STB/day, accompanied by a gradual rise in water cut from 10% to 70% over the simulation period. Cumulative oil recovery improved from 25% under primary recovery to approximately 45% with waterflooding, indicating a 20% incremental recovery due to secondary recovery efforts. The study highlights the importance of reservoir simulation tools such as CMG in designing and optimizing waterflood operations, predicting production performance, and evaluating reservoir management strategies. It concludes that waterflooding remains one of the most efficient and economical methods of improving oil recovery in mature fields when properly designed using robust simulation techniques.

In the petroleum industry, the accurate determination of hydrocarbons initially in place is critical for effective reservoir management and the formulation of efficient production strategies. This research focuses on the evaluation of a saturated oil reservoir in an onshore Niger Delta field through the application of Material Balance Analysis (MBA). The objectives of the study include estimating the initial oil in place, evaluating the presence and strength of an underlying aquifer, identifying the dominant reservoir drive mechanism, and recommending an optimal production scheme capable of maximizing economic recovery. For this research, the majority of the reservoir and production data were obtained from Nigerian National Petroleum Company (NNPC), which also provided access to the MBAL simulation software. MBAL is a simplified yet powerful analytical tool that applies the concept of material balance to characterize reservoir behavior. The program models the reservoir using a zero-dimensional (tank) approach, which does not explicitly account for geometry, drainage area, or well orientation, but provides valuable insights into fluid distribution and drive mechanisms by analyzing production and pressure performance. The results from the MBAL analysis indicate that the reservoir contains an estimated 250.258 MMSTB of oil initially in place, and the predicted volume of water in place to be 99788.4 MMft3 . Furthermore, the aquifer’s influence on reservoir pressure performance demonstrates that water drive is the predominant drive mechanism sustaining production. These findings provide a reliable basis for planning production strategies that optimize reservoir performance while enhancing ultimate recovery. In carrying out this research, valuable hands-on experience was gained in data handling, diagnostic plotting, and MBAL simulation. The work strengthened descriptive, technical and analytical competence in reservoir evaluation and provided deeper insight into the importance of accurate data interpretation for sustainable hydrocarbon recovery in the Niger Delta basin.

Managed Pressure Drilling (MPD) has emerged as a critical technology for addressing deepwater drilling challenges including narrow pressure windows, formation uncertainty, and wellbore instability. Despite proven benefits, limited research has comprehensively reviewed optimal MPD configurations and implementation strategies for deepwater environments. This systematic literature review analyzed multiple published sources to identify best practices, evaluate existing technologies, and provide evidence-based recommendations.The review identified four critical success factors: comprehensive planning, appropriate technical configurations, disciplined operational procedures, and effective team integration. Three case studies from Gulf of Mexico, East Malaysia, and Mediterranean demonstrated quantified improvements of 35-81% in performancemetrics with substantial cost savings including USD 3.5 million contingency avoidance. Analysis revealed that MPD effectiveness requires formation-specific customization, with economic benefits extending beyond cost reduction to risk mitigation and enabling access to challenging reserves. Persistent challenges include extended response times, equipment reliability concerns, lack of standardization, and economic evaluation uncertainties. Priority research areas recommended include advanced control systems, equipment reliability enhancement, standardization initiatives, and comprehensive economic frameworks. These findings provide valuable guidance for optimizing MPD application in deepwater drilling environments.

Natural gas, which can be found in conventional natural gas reservoirs as non-associated gas (NAG), associated gas (AG), or gas condensation products, is a combustible gaseous combination of gaseous hydrocarbons, very light liquid hydrocarbons, free water, water vapor, and other undesirable non- hydrocarbon gaseous and solid components. Water or water vapor is eliminated rom the streams of natural gas through the process of natural gas dehydration. Production, handling, and transportation of natural gas are hampered by the presence of water that is free in the gas. Therefore, it is imperative to eliminate a large portion moisture as feasible from the gas stream. While there are a number of ways to dehydrate natural gas, the following are the most idely used ones:

This project examines how sodium chloride (NaCl) affects the rheological properties of beneficiated gum Arabic-based drilling fluids and their blends with cocoyam starch, ginger extract, and xanthan gum. The aim was to develop an environmentally friendly drilling fluid that remains stable in saline environments. Laboratory tests were conducted using a Fann viscometer
to measure key properties such as plastic viscosity, yield point, and gel strength at NaCl concentrations of 7.5 g and 15 g. The results showed that moderate salt levels improved gel strength and yield point, while higher salt concentrations slightly reduced viscosity due to polymer chain tightening. Among all the tested samples, the gum Arabic–ginger and xanthan
gum blends performed best, showing strong salt tolerance and stable shear-thinning behavior described by the Herschel–Bulkley model. Overall, the study highlights gum Arabic’s potential as a natural, cost-effective, and sustainable alternative to synthetic polymers for drilling operations.

Temperature increases with depth as we drill through or within deep formations; therefore, producing from such high temperature zones involves several challenges to petroleum engineers in terms of drilling, completion, and production. This makes it necessary to study the rheology of drilling fluids and how it is affected by these changes. Laboratory tests were carried out to determine the mud weight, pH, plastic viscosity, yield point, gel strength of mud samples at different conditions of temperature and concentration of yam powder used as an additive. The first stage was to investigate how the mud properties of water-based Bentonite muds are affected by different concentration (3g, 5g, 7g and 9g) of yam powder added as an additive to improve the muds properties. The second stage was to investigate the effects of temperature on the mud properties at different concentrations of yam additive with a temperature variation of 28℃, 40℃, 60℃ and 80℃. From the results obtained, it could be seen that the mud weight, plastic viscosity, yield point and gel strength improved significantly but the pH reduced as the yam powder was added to the fresh mud at various concentrations. The mud weight, pH, plastic viscosity and yield point decreased as the temperature increased from 28℃ to 80℃. The gel strength showed increase with increasing temperature of 28℃ to 80℃. From this work, temperature has a remarkable effect on properties of drilling mud. Proper knowledge of the key factors governing the selection of drilling mud is critical for appropriate drilling mud selection because the behavior of the drilling mud under high temperature is extremely important for drilling geothermal wells and for drilling deep wells.

The prediction and control of emulsion tightness in oil fields is crucial for optimizing production processes and maintaining operational efficiency. This project focuses on developing a predictive and control model to assess and manage the tightness of emulsions in oil reservoirs. Emulsions, which are mixtures of oil and water, can significantly impact the efficiency of extraction and refining processes, leading to operational challenges and increased production costs. By employing a combination of empirical data analysis, computational modelling, and machine learning techniques, this research aims to predict emulsion behaviour under various reservoir conditions and control the factors influencing emulsion stability. The model incorporates reservoir characteristics, fluid properties, and production parameters to provide realtime insights and effective strategies for mitigating emulsion-related issues. Ultimately, the model aims to enhance oil recovery, reduce operational costs, and improve the overall efficiency of oil field operations.

In this study, the effect of two food waste materials, cassava peels, and plantain peels as local environmentally-friendly additives,on the pH, mud weight, viscosity and the fluid loss properties of water based mud was evaluated. The water based mud samples were formulated using bentonite, barite, distilled water with cassava peels and plantain peels in varying weight proportions. Mud weight and pH measurements, viscosity and the volume of fluid loss were measured. Experimental results indicated that at same concentration, the cassava peels had higher rheological properties compared with the plantain peels. However, the muds formed from the combination of cassava and plantain peels have better filtration control properties. Although the viscosity of the drilling fluid produced from the plantain peels were lower than that of the cassava peels, the cassava peels shows a
lower fluid loss than the plantain peels. Therefore, with proper quality control efforts, they could be used as a drilling mud additive for exploration and exploitation of oil and gas in Nigeria. It is also hoped that this work will open new market for the use of cassava and plantain waste.

In this study, the effect of two food waste materials, cassava peels, and plantain peels as local environmentally-friendly additives, on the pH, mud weight, viscosity and the fluid loss properties of water based mud was evaluated. The water based mud samples were formulated using bentonite, barite, distilled water with cassava peels and plantain peels in varying weight proportions. Mud weight and pH measurements, viscosity and the volume of fluid loss were measured. Experimental results indicated that at same concentration, the cassava peels had higher rheological properties compared with the plantain peels. However, the muds formed from the combination of cassava and plantain peels have better filtration control properties. Although the viscosity of the drilling fluid produced from the plantain peels were lower than that of the cassava peels, the cassava peels shows a lower fluid loss than the plantain peels. Therefore, with proper quality control efforts, they could be used as a drilling mud additive for exploration and
exploitation of oil and gas in Nigeria. It is also hoped that this work will open new market for the use of cassava and plantain waste.