bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Minimum Miscibility Pressure Between Heavy Oil – Supercritical Carbon Dioxide System Using the Slim Tube Method
Authors: Uzoho C. U. , Okorafor I. F. , Olomu D. O. , Achilike N. E. , Adesina O. D. , Onyekonwu M. O. 
Published: July 2023

Abstract
The minimum miscibility pressure is the lowest pressure at which the reservoir fluid can be subjected in order to achieve miscibility with the desired gas. In this experimental study, a 40-ft slim tube, Haste alloy coil with an outer diameter of ¼″ was used to determine the minimum miscibility pressure (MMP) of a Heavy Oil-CO2 System at reservoir conditions. The slim tube was saturated with crude oil from a Niger Delta Field at a constant temperature of 139.2°F after which, 1.2 PV of supercritical carbon dioxide was injected above the heavy oil bubble point pressure at a constant flowrate of 0.2cc/min. The flooding process continued until a high-pressure drop was observed with minimal oil recovered. It was seen that the displacement efficiency increased with an increase in experimental pressures beyond a point where its increase was nominal. However, the MMP for this study occurred at a reservoir pressure of 2042 psi which is the break-over point where no significant change in oil recovery was observed with a recovery above 70%OOIP. The determined MMP was used as a guide in a CO2-EOR and CO2 secondary mode flooding project using a Niger Delta and tight Berea Buff reservoir core samples. The result shows that MMP plays a vital role in any successful miscible flooding EOR project. In the era of carbon capture and sequestration, we can therefore capture carbon and use it for EOR. However, the MMP of the crude oil has to be determined.
Introducing Python Coding to Petroleum Engineering Undergraduates: Excerpts from a Teaching Experience
Authors: Mosobalaje O. O. , Orodu O. D. 
Published: July 2023

Abstract
The post-Covid world is witnessing a rise in automation and remote work models. Oilfield operations are becoming increasingly innovation-driven with advances such as digitalization technologies, smart fields and intelligent wells. Proliferation of data is extending career frontiers in data analytics, machine learning and artificial intelligence. Human competence in computer programming is a key enabler of these trends. As a contribution to the Nigerian oil/gas human resources development, the petroleum engineering program at Covenant University recently developed and is implementing a course module on Python programing with oil/gas applications. This paper documents the philosophy, pedagogy, and prospects of this initiative and provides a guide for its implementation across the Nigerian educational space.
The module opens with a seminar on the emerging oil/gas opportunities in data science – to stimulate students’ interest. Thereafter, a gentle introduction to computer programming is taught. At its core, the module teaches basics of Python programming language – input/output, objects (values, variables, keywords), conditional and repetitive structures, functions, lists, tuples and dictionaries. The module is enriched with applications in reservoir volumetrics, material balance equation, PVT properties, reservoir discretization and simulation. Hands-on experience is enhanced with class demos and take-home programming assignments featuring simple algorithms. Also, the course features a training on the use of distributed version control (GitHub) for collaboration between students and instructors. All course materials are available on an open-access GitHub repository, with hyperlinks embedded in lecture notes. Ultimately, the course assesses students’ skills with exams set in the context of quasi-real-life projects. The future prospects targeted in this initiative includes a follow-up module on petroleum data analytics and machine learning, incorporation of Python coding into other modules, and a short-course for industry professionals.
Energy Efficiency as a Key Driver for Environmental Sustainability in the Oil and Gas Sector in Nigeria.
Authors: Oruwari Humphrey Otombosoba , Ubani Chris 
Published: July 2023

Abstract
Energy efficiency is concerned with the ratio of benefits gained from an energy related operation or activity in comparison to the actual energy utilized in deriving that benefits. In essence energy efficiency means doing more with less energy and it involves all aspects of energy production This study investigated energy efficiency as a key driver of environmental sustainability in oil and gas sector in Nigeria. Inefficiency in energy use has brought a significant negative impact by increasing cost of production and emission of green house gases. The implications of this is that the cost of oil and gas operations will be high thereby reducing the profitability and increasing emission by green house gases. The study methodology used literature review and case study of other countries with focus on the oil and gas sector. The findings revealed that energy consumption in oilfields found significant potential for reducing costs through energy efficiency improvements and contributing to climate change mitigation through reducing green house gases emissions. Moreover, reducing oilfield energy costs reduced the overall cost of oil production. Efficiency gains lead to reduced emission, simply changes to field equipment or operating procedures can yield major efficiency gains in oil and gas operation. It is concluded the adoption of energy efficiency in energy intensive sectors with huge carbon foot print such as oil and gas sector will serve to decarbonize the economy and accelerate the nation towards climate change mitigation and sustainable development. The key to increasing energy efficiency and reducing environmental costs is having the right drivers through education, policy and legislation, financial incentives and technological advances. These drivers need to be integrated with both management and technology of the business to drive down cost. It will be crucial for oil and gas companies to improve energy efficiency in all the production process.
Investigation of the Impact of Surfactant Concentration on Gas Well Deliquification
Authors: Kinate Bright Bariakpoa , Nmegbu Chukwuma Godwin Jacob , Amadichuku Nyelebuchi 
Published: July 2023

Abstract
This work investigates the effect of surfactant concentrations on gas well deliquification and quantify the incremental gas production rate. A base model was built to verify the possibility of liquid loading behavior using the Turner velocity criteria. Foam lift was enabled and the well flow path was defined including the micro-annular space between the coiled tubing and the tubing strings. Different Surfactant concentrations of 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45 and 0.5mass percent were injected for an optimum concentration required to unload liquid from the gas well. Results reveals that the reservoir will deliver 13.315MMscf/day of gas across the completion into the wellbore when the pressure drawdown is maximum.The intersection of the inflow and outflow performance curves shows that the well was producing 2.09787 MMscf/day of gas which occurs where the Turner velocity criteria shows a potential issue (liquid loading). A gas production rate of 2.09787 MMscf/day was produced with no foam lift but with foam lift and 0.05mass% of surfactant injected, the well production rate increases from 2.09787 MMscf/day to 7.60823MMscf/day. The result shows that a surfactant mass percent of about 0.4% will maximize gas production from the well producing 7.71049MMscf/day. Results reveal that surfactant should not be injected at concentration above the critical micelles concentration (CMC) as it will lead to a significant increase in the frictional component of the fluid pressure loss due to the rheology of the foam.
Investigative Approaches to Troubleshooting and Remediating Sub-Optimal Gas Lift Performance in a Dual Completion Well
Authors: Akinola Obembe , Olufisayo Fagbowore , Ebikeme Adowei , Olumide Taiwo , Aluba Oragwu , Clement Chukwuka 
Published: July 2023

Abstract
Gas lift is said to be one of the most forgiving forms of artificial lift techniques because even a poorly designed gas lift system will lead to some production of fluids. As a result, the tendency exists for Production Engineers to pay little attention to designing and maintaining optimal gas lift systems. Some unique considerations are required for a dual gas lift system where both strings in a dual completion are on gas lift. Using a case study, this paper highlights key investigative questions and assessments to understand the individual well string performances, assess optimal contribution of both strings and optimal distribution of the injected gas. This paper focuses on the gas lift optimization on Well-AX SS which experienced production decline from about 1,000 BOPD to 40 BOPD.
The highlights of the methods employed involved investigating for communication between strings, identifying the string with highest production potential, determining optimal gas lift valve depth, and ensuring no surface network bottleneck exists. With industry emphasis on low-cost oil, it has become critical to minimize the Operating Expense (OPEX) by ensuring optimal gas lift injection into wells. After investigation and assessment of the production potential and the gas lift injection status, the gas lift injection was redesigned, and optimal gas lift design recommended. The work-over executed involved isolating the source of communication, shutting in the completion with lower potential and optimizing the gas lift system of the more productive string. This work-over led to an increase in production of 850 BOPD.
One of the key challenges to optimal gas lift is accurate gas measurement and understanding the split of gas between each string in a dual completion. Lessons learned from this assessment include obtaining robust and recent surveillance data for well performance assessment and thorough evaluation of production strings to ascertain the injection depth of gas lift gas.
Decommissioning and Abandonment of Oil and Gas Assets – A Case for Coexisting with Mother Nature
Authors: Akanegbu Stanley , Agbogu George , Okonkwo Ngozi , Nnanna Erasmus , Imoyo Olusola 
Published: July 2023

Abstract
All oil and gas assets including wells, flowlines, production facilities, and all surface structures installed as part of the network of facilities required for the safe exploration, development and production of hydrocarbons are required by law to be properly decommissioned at the end of their useful life, and the environment restored to her original form in sync with mother nature. Of particular significance are the considerations that are given to Oil and Gas well Decommissioning and Abandonment (D&A) owing to their extensive sub-surface footprint where achieving acceptable D&A at their end of the useful life requires significant upfront planning during the early stages of project maturation and involves projections and decisions being made around funding, timing, and extent of the decommissioning that needs to be done including proper zonal abandonment of respective reservoirs, retrieval of well construction hardware and sub-surface plug back of the well to ensure hydrocarbon never finds their way to surface under any circumstance after abandonment of the well. The requirement and extent of Decommissioning and Abandonment of oil and gas assets is a statutory requirement governed by the legislature in place in respective countries of operation and governed by international best practices that ensures environmental sustainability, and the provisions for D&A is made in each operator's financial statements to recognize the liability for D&A at the end of the license expiry or at end of production. This mandated by international financial reporting standards (IFRS). The D&A process is fraught with a lot of technical and non-technical challenges, which require significant upfront identification, and robust risk identification and mitigation in order to be able to manage them and be in compliance.
This paper reviews the D&A practice in Nigeria, looks at candidate identification strategies, breaks down the methodology and best practices involved in D&A operations for wells, and x-rays the requirements for open-hole and cased-hole abandonment as well as the logging and testing requirements that guides the decisions made. The risks involved in D&A projects would be analyzed and insights into how they tie back to the mitigations put in place to ensure successful decommissioning and restorations of the assets reviewed, and how these all connects back to nature with a view to sustaining global best practices for returning our environment to her clean and green state before exploration activities disrupted nature's balance would be established.
Inhibition Effect of Order Brassicales Plant Extract (BPE) on Methane Gas Hydrate Formation in a Gas Dominated System
Authors: Wachikwu-Elechi V. U. , Ikiensikimama S. S. , Ajienka J. A. 
Published: July 2023

Abstract
Problems related to gas hydrate formation abound in oil field operations due to deep offshore activities, leading to severe adverse effects and safety problems all of which add to operating cost (OPEX). Prevention of these problems is key. The use THIs and KHIs have been explored but has their disadvantages. Due to the alarming rate of environmental degradation via toxic substances, there is an urgent need for friendly alternatives for both humans and the environment. This study compares the use of Brassicales Extract (BPE) and Poly n-vinyl caprolactam (N-VCap) as gas hydrate inhibitors. The BPE was evaluated using a locally fabricated stainless pipe mini flow loop. Hydrate formation and inhibition experiments were carried out for a period of 120 minutes with pressure and temperature readings recorded every 2 minutes. A rapid decrease in pressure and sudden increase in temperature are pointers to hydrate formation in the constant volume batch process loop. Microsoft excel was used to generate plots relevant to hydrate formation and inhibition. The various pressure plots showed that the BPE performed better than the conventional in most weight percentages considered. Pressure decline and temperature increase was more regulated in the systems with BPE unlike in the uninhibited experiment. The Volume of gas used up in the BPE inhibited system were 23.3, 14.7, 16.7, 15.3 and 12.7% for 0.01-0.05wt% respectively while for N-VCap, the volume of gas used up for the same weight percentage were 24, 17.3,22, 10.7 and 29.3% at the end of the experiments. BPE has inhibition efficiency values of 69.3, 80.7, 78.07, 79.82 and 83.3% for 0.01-0.05wt% respectively while that of the synthetic inhibitor was 68.42, 77.2, 71.1, 86 and 61.4%. It is recommended that the BPE be developed for gas hydrate inhibition because it did very well and is environmentally friendly unlike the N-VCap which is a toxicant.
Safeguarding Export Gas Supply with Subsurface Disposal of Produced Water: The MXC Approach to Liquid Handling
Authors: Udobata Uchenna , Ogbunude Basil , Muzan Eelah , Chiroma Barka , Musa Nabage , Maxwell-Amgbaduba Sunday , Monday Nanpan , Okereke Onyedikachi , Tamunotonye Biambo , Femi Obakhena , Chinedu Nwachukwu 
Published: July 2023

Abstract
Unprocessed gas from the gas wells in the nearby fields is routed through the production manifolds to the processing trains in gas plants. The associated liquids from the treatment process accumulate in a stabilization tank, where it undergoes separation by gravity into condensate and water and therefore needs to be evacuated to sustain gas production. The base design strategy for MXC's export gas supply from gas plants A and B relies on two major export pipelines as the primary evacuation routes for the accumulated condensate and water.
In the absence of these major export pipelines, the condensate can be evacuated by spiking via the gas export pipeline to the LNG plant. However, the only available option to evacuate the produced water was by barging to the export terminal for subsequent disposal into the sea. This option was unsustainable due to logistics, insecurity, and operating costs. Inability to dispose of the produced water would result in water level build-up in the condensate stabilization tank, which impacts the ability to spike condensate, forced reduction in gas production as much as 500MMscf/d or complete gas plant shut down with deferments as high as 1.2 Bscf/d from both gas plants. With the prevailing external context of frequent and prolonged outages of the export pipelines, resulting in gas deferment, and external regulatory requirements to limit evacuation of produced water to the sea, it became imperative to create additional options for liquid evacuation to guarantee the security of export gas supply as well as meet regulatory requirements.
Produced water disposal into the subsurface was considered a critical and essential strategy for building this robustness. This paper discusses the strategy adopted by MXC to build water disposal capacity in Plant A, comply with regulator stipulations, and sustain gas supply from MXC's gas plants. It highlights the initial trade-offs and challenges in developing and managing the system and the best practices adopted to improve system reliability.
Using Machine Learning to Predict Permeability from Well Logs: A Comparative Study of Different Models
Authors: Asimiea Nicholas Walson , Ebere Emmanuella Nkiruka 
Published: July 2023

Abstract
Permeability is a crucial parameter in reservoir engineering, as it determines how easily fluids can flow through subsurface rocks. Traditional methods of measuring permeability are expensive, error-prone and time-consuming, which has led to the development of machine learning models that can predict permeability based on well-log data. This study aims to determine the most effective machine learning models for predicting permeability based on available well-log data. The study covers a detailed explanation of the data-gathering and pre-processing techniques used. Four input features were used in the models, namely gamma ray (GR), bulk density (RHOB), neutron porosity (NPHI), and resistivity (RT). Six different models were trained and evaluated based on their performance, namely linear regression, support vector machine, decision trees, gradient boosting, multi-layer perceptron, and random forest models. The models were evaluated based on their Mean Squared Error and RSquare values. Our results showed that the random forest model outperformed the other models, achieving a Mean Squared Error (MSE) value of 0.88. The multi-layer perceptron and gradient boosting models also showed promising results, achieving MSE values of 0.81 each. These findings suggest that machine learning models can be a powerful tool for predicting permeability from well-log data, and the random forest model, in particular, holds great promise for future modelling efforts in this area.
Evaluation of the Potential of Watermelon Rind as a Ph Enhancer for Water-Based Drilling Fluid
Authors: Salihu A. , Sani I. , Ibrahim K. , Nzerem P. , Gimba A. S. B 
Published: July 2023

Abstract
How effectively drilling mud's qualities, such as pH, mud weight, viscosity, etc. are maintained determines how successful it is. Therefore, it is essential to choose drilling fluids, additives, and its composition carefully. The urgent need for product substitution, cost cutting, waste management, and environmental protection was connected with this study project. This research attempted to determine whether potassium hydroxide might be replaced by watermelon rinds (KOH). Watermelon rinds are a common household waste that is commonly available, easily accessible, and biodegradable. They also contain a high amount of potassium. The method used to synthesize KOH from the watermelon rind is caustification of potassium carbonate (K2CO3) from calcining of processed watermelon rind (dried and pulverized). A laboratory barrel of water-based mud was prepared using Wyoming bentonite clay. The produced additives from the watermelon rinds were added to the mud at different concentrations. The results obtained from the experiments conducted showed that the values pH values for synthesized KOH gave comparable results to the commercial KOH. The pH increase was 8.62%, 12.06%, 24.25% and 39.31% for watermelon rind (processed rind), ash, synthesized potassium carbonate and synthesized KOH respectively at maximum concentration. The four additives used increased filtrate loss and mud cake thickness, the rheological properties and mud weight of the mud. In conclusion as a pH enhancer, the synthesized KOH from watermelon rind is suitable and also has secondary effects on mud weight, filtration properties and rheological properties.
Operationalising Process Safety in Gas Lift Operations - Okom Field Experience
Authors: Obong Benjamin , Ofia Ifeanyichukwu , Balogun Bayo , Ukenye Sunday , Oginni Abiodun , Mozeh James , Azibapu Franklin , Ewuzie Theresa 
Published: July 2023

Abstract
The oil and gas industry faces inherent hazards that can result in process safety incidents, such as leaks, fires, and explosions, causing harm to people, assets and the environment. Process safety requires a comprehensive commitment from everyone involved, going beyond policy compliance. Each specialization within the industry has a role in maintaining a safe work area and ensuring sustainable oil and gas production.
Process safety entails the proper design, safe operation, and maintenance of physical assets like drilling rigs, platforms, and processing facilities to prevent the release of hazardous materials. It relies on proactive leadership and competent personnel to achieve the goal of zero harm to employees, contractors, communities, and the environment. A crucial aspect of process safety management is the continuous evaluation of potential risks, the identification of preventive measures, and the assessment of the effectiveness of existing controls. Many process safety incidents in the industry have resulted from a failure to recognize and mitigate risks associated with changes. The Piper Alpha disaster in 1988 serves as a tragic example of such a failure.
Gas lift systems can present integrity challenges. Operators have prioritized addressing well integrity compromises in gas lift systems, especially regarding the check valve in gas lift valves.
The Okom field with over fifty-nine (59) years of production, began using artificial lift gas in 1993 to maximize oil production but has encountered challenges in its gas lift system operations, such as reverse flow issues and liquid fouling of gas lift manifolds during shutdowns, which further emphasizes the importance of process safety management in its operations. Aging infrastructure further underscores the criticality of process safety for mature assets like Okom.
This paper focuses on the integrated approach employed by the Okom Asset team to address process safety challenges, maintain gas lift integrity, manage major accident hazards, and consistently deliver process safety fundamentals across its assets.