Papers by African Journal of Engineering and Environment Research
African Journal of Engineering and Environment Research Vol.7(2), 2025
This study investigated the concentration, distribution, and modes of occurrences of rare earth e... more This study investigated the concentration, distribution, and modes of occurrences of rare earth elements in coal from the Middle Benue Trough, northcentral Nigeria. This basin comprise one coal bearing Formation i.e. Awgu Formation. Using inductively coupled plasma mass spectrometry (ICP-MS), we analysed 28 coal samples from the Awgu Formation. Results indicated that the total REE concentrations (̩ REE) were similar to REE-enriched shales, running as high as 110.01 ppm. The distribution patterns show LREE enrichment (LREE/HREE = 2.78-9.41) with positive Eu anomalies and suboxic Ce/Ce* signatures, suggesting terrigenous input and redox shifts during deposition. Low LREE/HREE ratios and negative Ce anomalies imply a robust organic connection of REEs and little oxidative breakdown. These results identify the REE signature as B-type, suggesting stable provenance with no diagenetic change. The findings also highlight intricate depositional patterns in the Turonian-Santonian phase of the Benue Trough, hence stressing the impact of volcanic ash and hinterland weathering. Through the combination of trace element geochemistry and stratigraphic context, this study offers significant new information on the modes of occurrence and extraction potential of REEs in Nigerian coals. In addition to supporting the environmental viability of coal-based REE extraction in sub-Saharan Africa, the implications extend beyond energy transition plans, positioning Nigeria as a stakeholder in the geopolitics of essential minerals.
African Journal of Engineering and Environment Research Vol.7(2), 2025
The oil and gas industry plays a vast role in the socioeconomic development and political advance... more The oil and gas industry plays a vast role in the socioeconomic development and political advancement of Nigeria. Despite the numerous benefits, a lot of environmental aspects are associated with petroleum and gas production facilities in the Niger Delta Region. Result of field measurement around an oil and gas facility in Rivers State indicated that high concentrations of CH4, SO2, NO2, NH3 and H2S up to 50,000ppm, 5ppm, 5ppn, 10ppm and 506ppm respectively. Field reports and statistical data indicated an estimated 350,107.43 barrels of petroleum were spilled into the Niger Delta environment between 2010 and 2019; the highest volume of 157,098.96 barrels (45%) spilled in Rives State, followed by Delta State with 79,375.65 barrels (23%) and Bayelsa State with 63,123.19 barrels (18%); crude oil theft accounting for 47%, sabotage accounting for 35%, while operational, equipment failures and mystery spills accounted for 18% of total oil spilled. Approximately, 1.42 billion million standard cubic feet (mscf) of natural gas was flared in selected 7 states in Nigeria between 2012 and 2019; 75.7 million tonnes of CO2 are emitted into the atmosphere; an estimate of 4. 94billion US Dollars is lost in 6 states between 2012 and 2019 due to gas flaring; approximately 141.6 thousand Giga Watt-hour of electricity is also lost. Enormous volumes of hazardous drilling waste/chemicals and wastewater effluent are discharged into the environment. The air, land, water resources, both terrestrial and aquatic plants and animals in the Niger Delta are adversely devastated. The ecological systems, public health, agriculture, natural resources and economic livelihoods have been significantly degraded. Hence, the study highlighted the need for all stakeholders, particularly the government and multinational oil and gas companies to quickly intervene and take urgent measures that save the Niger Delta environment and its inhabitants from imminent destruction.
African Journal of Engineering and Environment Research Vol.7(2), 2025
The rapid integration of technology into daily life has made the use and exchange of information ... more The rapid integration of technology into daily life has made the use and exchange of information inevitable, exposing individuals and institutions to rising risks of data breaches. In Nigeria, a nation undergoing rapid digital transformation, addressing these vulnerabilities is essential to fully realize the benefits of a burgeoning digital economy. Despite the enactment of the Nigeria Data Protection Act (NDPA) and the establishment of institutional frameworks, critical implementation deficiencies persist. These gaps, driven by corruption, underfunded agencies, and weak enforcement mechanisms, leave the nation's data ecosystem vulnerable to high-profile breaches. This article examines key incidents involving government and corporate actors and assesses the strengths and shortcomings of Nigeria's current data protection regime. It explores the broader implications for privacy, institutional trust, and national security, while emphasizing the urgent need to strengthen the Nigeria Data Protection Commission (NDPC), enforce accountability across sectors, and increase public awareness. Finally, it calls for local and international cooperation to build capacity, promote transparency, and ensure that both state and private entities adhere to best practices. Bridging the gap between legislation and enforcement is key to establishing Nigeria as a leader in data protection and digital governance in Africa.
African Journal of Engineering and Environment Research Vol.7(2), 2025
The challenge of artisanal petroleum products has been a national issue. Artisanal petroleum prod... more The challenge of artisanal petroleum products has been a national issue. Artisanal petroleum products are diesel, petrol (gasoline) and kerosene are obtained from the illegal refineries located in the creeks. Artisan refineries are illegal because they do not have licence and technologies to operate, and physiochemical properties of their products had not been studied to ascertain the quality. Therefore, the study sought to investigate the physiochemical properties of the artisan-refined petroleum products such as diesel, kerosene and petrol (gasoline) in comparison with the imported sample (reference). The investigation was done using ASTM standard procedures. The results of pH readings for reference samples (Diesel, kerosene and petrol) and the artisan-refined samples (Diesel, kerosene and petrol) were 7.5, 5.9 and 7.25 and 6.7, 5.35 and 6.10 respectively. The flash points of artisan diesel, petrol and kerosene were 50,-32 and 39 respectively while the flash points of imported samples of diesel, petrol and kerosene were 48,-228 and 39 respectively. All other physiochemical properties such as specific gravity, API gravity and impurity, Kinematic viscosity, ASTM colour and Saybolt of the illegally refined product showed some variations with those of the reference samples. From the results, it could be deduced that artisan petroleum products had poor quality and did not meet ASTM specification. These irregular characteristics of the illegal products damage engines of automobiles, causes environmental pollution and health hazard to man.
Petroleum contamination is a known environmental challenge in the South-South region of Nigeria. ... more Petroleum contamination is a known environmental challenge in the South-South region of Nigeria. This study investigated the fungal population and diversity of diesel contaminated soil close to a petroleum dispensing station in Port Harcourt. Four composite soil samples were collected equidistance from the polluted site and designated as A, B, C and D. An unpolluted soil sample designated E served as control. The cultivation and isolation of fungi from the soil samples were carried out by plating aliquot of serially diluted samples onto sterile Sabouraud Dextrose Agar in Petri dishes. Cultured plates were incubated at room temperature for 3 to 5 days for the growth of fungi. Colonies which developed were counted and identified through macroscopic and microscopic methods. Fungal population were found to decrease in the diesel oil polluted samples (A, B, C, and D) and increased in the unpolluted soil sample E. This shows that the diesel oil has a decreasing effect on soil fungi population as depicted in the drop of the mean count spore forming units (SFU) from 620 x10 5 SFU/gt to 2.15 x 10 5 SFU/g with the control recording the highest count of fungi. Some fungi isolated from the soils and identified were: Penicillium chrysogenum, Aspergillus niger, Rhizopus oligiosporus, Fusarium solani, Thrichoderma sp., Alternaria sp., Pichia sp. And other species of Aspergillus. Amongst the isolates, Aspergillus niver and Penicillum chrysogenum were predominant and showed fast growth rates and are suggestive for utilization and biodegradation of diesel hydrocarbon in the polluted soils.
African Journal of Engineering and Environment Research Vol.7(2), 2025
The success of drilling oil and gas wells are highly dependent on the drilling fluid used for dri... more The success of drilling oil and gas wells are highly dependent on the drilling fluid used for drilling and completion. The choice of the drilling fluid and its additives becomes more complex especially when more products of different functions are introduced from time to time. Drilling operations face great technical challenges with drilling problem especially in deep water operation. When exposed to high pressure high temperature (HPHT) conditions, drilling in deep wells will have negative impact on drilling fluids rheological properties. One of the major factors contributing to non-productive time (NPT) in drilling industry is lost circulation, which usually occurs during overbalance drilling operation and is defined as the partial or complete loss of drilling mud into the fracture. In this study, efforts were made using computational analysis to predict an optimal operations of an existing drilling fluid line systems, the operations has provided valuable insights into both pressure and velocity distribution of the systems. The results reveal significant variations in pressure gradients along the fluid line, with certain regions exhibiting high-pressure zones that may contribute to energy losses and potential wear on the pipeline. Additionally, the velocity distribution analysis highlights areas of uneven flow, including zones of high velocity that could lead to turbulence and inefficiencies, as well as low-velocity regions that may cause sedimentation or blockages. The results for the 3 predicted fluid samples: water (H2O), hydrogen peroxide (H2O2), and hydrochloric acid (HCl) were validated with the open literature. These findings emphasize the importance of optimizing the fluid line design and operational parameters to improve the overall efficiency and reliability of the system. By addressing pressure and velocity irregularities, the drilling fluid-line can achieve enhanced performance, reduced energy consumption, and extended operational life.
African Journal of Engineering and Environment Research Vol.7(2), 2025
This study aimed to evaluate Aspergillus flavus' potential in remediating bitumen-contaminated so... more This study aimed to evaluate Aspergillus flavus' potential in remediating bitumen-contaminated soil. Aspergillus flavus, previously isolated from a crude oil-contaminated soil sample in Nigeria's Niger Delta region, was sourced from the Old Biology laboratory of Ajayi Crowther University, Oyo state. Bitumen was purchased from Ogunpa market, Ibadan and soil samples from the university's Old Biology Laboratory area. Twenty-four soil samples were collected, with eighteen intentionally contaminated with bitumen and six kept as uncontaminated controls. Aspergillus flavus broth was inoculated into eight contaminated samples. Over three months, microbial and physico-chemical parameters of the soil samples were analyzed using standard methods, including monitoring changes in total petroleum hydrocarbon levels. Microbial counts were enumerated biweekly and compared. Field mycoremediation lasted for 12 weeks. In contaminated, sterilized soil treated with Aspergillus flavus, fungal counts initially increased until the 8th week, followed by a decline. Initial contamination yielded a fungal count of 2.5 x 10^6 cfu/g, decreasing to 2.3 x 10^5 cfu/g after 3 months. Total petroleum hydrocarbon in treated soil decreased from 4.60 ppm to 1.06 ppm, indicating a progressive reduction in oil concentration. The Aspergillus flavus isolate exhibited potential for bitumen degradation, suggesting its viability for environmental cleanup of bitumen-contaminated soil.
African Journal of Engineering and Environment Research Vol.7(2) 2025, 2025
Reservoir analysis is a vital component of hydrocarbon exploration and production, offering cruci... more Reservoir analysis is a vital component of hydrocarbon exploration and production, offering crucial insights into reservoir characteristics, fluid dynamics, and prospective production efficacy. This article provides an overview of the utilization of linked geophysical well logging and spatial modelling in improving reservoir analysis. The integration of geophysical well logging and spatial modelling facilitates a thorough comprehension of reservoir characteristics and variabilities, resulting in enhanced reservoir models and optimized reservoir management approaches. Geophysical well logging entails the analysis of well log data, core measurements, and laboratory studies to quantify reservoir characteristics like porosity, permeability, fluid saturations, and lithology. Spatial modelling, encompassing variogram analysis, spatial interpolation, and stochastic simulation, is employed to represent reservoir features and uncertainties, integrating available data and incorporating spatial variability. The main advantages of combining geophysical well logging with spatial modelling include increased reservoir analysis, improved reservoir modelling accuracy, optimized well location and production plans, and decreased exploration and development risks. Case studies illustrate the use of integrated methodologies across diverse reservoir types, including as clastic, carbonate, and unconventional reservoirs, emphasizing the efficacy of these techniques in enhancing reservoir comprehension and performance forecasting. Challenges and limits related to combine geophysical well logging and spatial modelling encompass data quality and availability, uncertainty quantification, computational complexity, and model validation. Confronting these difficulties necessitates a multidisciplinary strategy, entailing cooperation among geoscientists, reservoir engineers, reservoir geophysicists, and data scientists, with progress in data collecting, processing, and modelling methodologies. The combined application of geophysical well logging and spatial modelling has substantial prospects for advancing reservoir analysis and optimizing reservoir management techniques. By utilizing existing data and integrating interdisciplinary skills, operators may enhance their comprehension of reservoir behavior, refine production methods, and improve hydrocarbon recovery from underground reservoirs. Ongoing research and improvement in coupled Reservoir Analysis methodologies are crucial for tackling issues and realizing the whole potential of hydrocarbon resources sustainably and efficiently.
African Journal of Engineering and Environment Research Vol.7(2) 2025, 2025
Sound is produced in every human activity. High levels of occupational noise remain a problem in ... more Sound is produced in every human activity. High levels of occupational noise remain a problem in many workplaces all over the world. Therefore, the importance of assessing occupational noise in artesian welding workshops and its impact on the workers cannot be over emphasized. This study measured and analyzed noise levels and its potential impacts among artesian welders in Port Harcourt metropolis. Noise levels produced in twenty artesian welding workshops in Port Harcourt metropolis were monitored using a smart sensor digital sound level meter, model AS 824. Noise descriptors, L10, L50, L90, noise logarithm average (Lavg), equivalent noise levels (Leq), noise climate (NC), noise pollution level (Lnp) were evaluated. The study showed that the used electric generators constituted the highest noise source in the artisan welding workshops. Noise levels in the artesian welding workshops ranged between 68.9 and 106.6dBA. The study showed high fluctuation of noise levels in 80% of the studied artisan welding workshops, with mean noise values exceeding permissible limit. Lavg values ranged between 80.2 and 97.6dBA; Leq values ranged between 82.2 and 98.8dBA; L10 ranged between 84.4 and 102.6dBA; L50 ranged between 76.6 and 96.2 dBA; L90 ranged between 72.8 and 90.2dBA. Noise pollution levels (Lnp) ranged between 86.1 and 125.9dBA. Conclusively, the study demonstrated that a significant number of artisan welding workers in Port Harcourt metropolis are exposed to high noise pollution, which may adversely affect their health. Therefore, the use of hearing protectors is recommended for artesian welders, which should be made mandatory to protect them against high noise exposure.
African Journal of Engineering and Environment Research Vol.7(1) 2025, 2025
National energy policies, politics of climate change and the environment affect energy supply cha... more National energy policies, politics of climate change and the environment affect energy supply chains and energy access, known to be proportional to rapid economic growth and industrialization drive of both developing and developed nations. While energy access is critical to sustainable development, the resources that provide links to direct access are in limited supply all over the world. Natural gas resources are one of the cleanest sources of energy and are also in high demand but limited in supply. Moreover, gas infrastructure such as pipeline networks, storage facilities are not readily available neither is the cost of construction, operation and maintenance affordable. The changing climatic conditions and environmental variance also contribute to the challenges of making gas resource and infrastructure accessible. Most of these challenges and other factors are consequences of established Management structure. In this paper, gas infrastructural development for enhanced industrialization was examined to determine the effectiveness and compliance level of government policy implementation. Strategic Management policies for the initial design, contract procurement, construction and commissioning stages were statistically analysed from hands-on real time data. A historical review of previous gas infrastructure and pipeline networks in the country were undertaken to ascertain the parametric design data. The Calabar-Umuahia-Ajaokuta (CUA) and the Ajaokuta-Abuja-Kano (AAK) are two streams of the Trans-Nigeria Gas Pipelines for transporting natural gas from areas of high concentrations to areas of high demands in the country. It was established that policy fluctuation, funding releases, dearth of in-country manpower and topological variance contributed substantially to the inconclusiveness of the Trans-Nigeria gas pipeline project for over a decade. This paper is therefore useful for decision-making and policy formulation on gas development.
African Journal of Engineering and Environment Research Vol.7(1) 2025, 2025
Spill sites, the proximity of workshops and flow stations to various ecosystems, coupled with the... more Spill sites, the proximity of workshops and flow stations to various ecosystems, coupled with the improper handling and disposal of waste oil, has led to the inadvertent release of petroleum hydrocarbons into the surrounding soil. This contamination poses a significant environmental challenge as it has the potential to disrupt soil fertility dynamics, including nutrient availability, microbial activity, and overall ecosystem health. The aim of this work is to ascertain the effect of petroleum level (waste oil) on soil fertility using Ajeokpori Ogale Eleme as a case study. Two sites, Location A (LC-A) and Location B (LC-B) were assessed by collecting soil samples from different points at depths of 0.15m and 0.30m respectively and analyzed for Ammonium, Nitrate, Sulphate, and Soil Carbonate. However, experimental results shows varying values of each parameter as compared to the control sample taken 100m away from spill site. Highest TPH values for site LC-A (6232 mg/kg) and LC-B (6648 mg/kg) clearly overshoots the EGASPIN standards. Nitrate and Ammonium levels were significantly lower at all contaminated points compared to the control, indicating a consistent disruption of nitrogen cycling. Consequently, LC-A displayed elevated iron levels, indicative of potential anaerobic conditions caused by pollution, while LC-B exhibited varying manganese levels and site-specific fluctuations in potassium and calcium. This implies that the soil health has been tampered with as a result of the oil spill and remediation must be done to restore the soil to its origin state.
African Journal of Engineering and Environment Research Vol.7(1) 2025, 2025
The effects of corrosion and hydrate formation on carbon steel pipeline is a major challenge to t... more The effects of corrosion and hydrate formation on carbon steel pipeline is a major challenge to the oil and gas industry. These hydrates are often encountered during multiphase flow of fluid and the problem is more significant in transient operations. Different types and grades of inhibitors (both thermodynamics and kinetic) are applied to the pipelines to avoid hydrate formation, especially when the pipelines are operated under high-pressure and low-temperature conditions. However, these thermodynamic and kinetic inhibitors are quite expensive and are not environmentally friendly. In this paper, the inhibition performance of a local inhibitor Saccharum Officinarum (SAOF) on X-65 carbon steel in deaerated environment were evaluated at varying conditions using a flow loop. Experimental results obtained were recorded and analyzed to determine the efficiencies of the inhibitors used at varies conditions of temperature, pressure and concentrations. The results obtained shows that the local inhibitor perform extremely well compared to the conventional inhibitor, and are found to be very effective in reducing the hydrate formation of X65 carbon steel compared to the conventional inhibitor at the specified conditions and concentrations. Consequently, It was noted that the optimum inhibition capacity occurred at 0.05 wt. % and prevented hydrate formation at declined temperature of 6.5 o C.
African Journal of Engineering and Environment Research Vol.7(1) 2025, 2025
The quest of living in a healthy environment and exploring a sustainable diverse energy-use towar... more The quest of living in a healthy environment and exploring a sustainable diverse energy-use toward improve economy has brought the continuous research to convert farm and municipal solid wastes (MSW) to useful energy. This study presents a case scenario on agricultural and solid waste generation, material recovery and the recycling potential of MSW in Maiduguri, Nigeria. The weights of the farm and MSW generation were estimated, while the energy and power potentials were estimated using thermo-chemical conversion model, from selected locations and tested within five planned areas; which are the General hospital, Gomshey dumping spot, State secretariat, University of Maiduguri campus, and University farms area of the Maiduguri metropolis. The mathematical model predicted 18702.87 kW/h of the energy potential and 779.29 kW/h of the power generation potential, these are appreciating values of energy potential and power generation potential found to be generated within the area studied. In summary, the study was concluded on possible investment opportunities to enhance the state resources utilization for energy purpose, increase in gross domestic project (GDP) and employment opportunity.
African Journal of Engineering and Environment Research Vol.7(1) 2025, 2025
Forensic audit analysis investigates the ideal fingerprint of nuclear or radioactive materials wi... more Forensic audit analysis investigates the ideal fingerprint of nuclear or radioactive materials within regulatory control, to aid attribution process. It is as fundamental part of a strong nuclear security program as establishment of a nuclear power plant. Fingerprints of uranium and thorium concentration, uranium isotopic and activity ratio, rare-earth elements patterns, trace impurities elements and age is determined to avoid dangerous radionuclides seepages into the environment. They provide specific information on the origin and production process of uranium bearing materials. This paper evaluate the audit processes in the investigation of the fingerprints and their applications in four uranium ore mined samples from parts of northern Nigeria (XR, M1, MII and MK), using integrated Inductive Couple Plasma Mass Spectrometric (IIC-PMS) analytical techniques. Results showed concentration range for uranium as 0.084±0.003 ppm to 73.965±1.371 ppm, equivalent to 1.053±0.033 Bq/kg to 924.566 Bq/kg; thorium had 0.055±0.006 ppm to 5.410±0.318 ppm, equivalent to 0.224±0.027 Bq/kg to 21.966±1.289 Bq/kg. The values for the locations vary significantly hence serve as the fingerprint of the areas. 235 U/ 238 U and 232 Th/ 238 U ratios had comparable values with standard of 0.047 and 0.001±7.96E-06-1.333±0.039 respectively. Both were analyzed by ANOVA and level of statistical significance of the variations identified as unique fingerprints. Isotopic ratios of 87 Sr/ 86 Sr (0.15126 ± 7.8505E-17), 143 Nd/ 144 Nd (0.71429 ± 7.85E-17) and 208 Pb/ 206 Pb (2.17427) had invariant but comparable values not distinct for fingerprint but can serve as supplementary information. The 232 Th/ 238 U isotopic ratio was applied to the chronometry of the samples. Age range of 4.506E+06 ± 5.126E+04 to 6.094E+09 ± 1.317E+08 years is comparable with the age of the Earth (4.543E+09 years). Study of viable fingerprints using other set up and technique such as LA-ICP-MS to differentiate between mines in the study area is recommended. This study is important for informed decision making and policy formulation on nuclear energy in Nigeria.
African Journal of Engineering and Environment Research Vol.7(1) 2025, 2025
Failures of engineering structures such as buildings and roads erected on expansive soils that oc... more Failures of engineering structures such as buildings and roads erected on expansive soils that occur extensively in the study area have been observed. Expansive soils are a clayey soil that swells or increases in volume when in contact with water but also shrinks or decreases in volume when the water is removed. This study was undertaken to evaluate the engineering properties of soils in the study area Nibo and environs, in relation to the failures of engineering structures in the areas. The study area is located bounded by latitude 60 101N and longitude 70 41 1.111E. A surface Geological mapping of the area revealed that there are two dominant formations in the area; the Eocene Nanka Formation and the Paleocene Imo Formation. A total of 9 soil samples were collected in different locations of the study area and their geotechnical properties determined in the laboratory. The geotechnical properties analyzed in the laboratory includes: sieve analysis and atterberg limit test. Water samples were also taken to analyze the Hydro geochemical properties so as to determine its portability. Results from the sieve analysis showed that soil samples analyzed are poorly graded with grain sizes ranging from medium to coarse sands, the Atterberg limit test shows that shales found in the shaley areas has high plasticity thus having high swelling potential while soils obtained from sandy areas exhibited low to medium plasticity thus suitable as foundation materials. Result from the water analysis carried out shows that the water resources present in the area do not meet up with the World Health Organization (W.H.O) standard and hence not potable. The area has industrial earth materials such as clay, laterite, sandstone and ironstone which are actively quarried for various industrial purposes.
African Journal of Engineering and Environment Research Vol.6(2) 2024, 2024
Conventional demulsifier (chemical) are still been used until now in many oil industries with the... more Conventional demulsifier (chemical) are still been used until now in many oil industries with the attendant formulas been both expensive and harmful for the environment. In this research, the new formula of local demulsifier has been tested with palm oil, glycerin, and Potassium Hydroxide (KOH). These materials are friendly for the environment and contain hexane group and octadecenoic acid which are basic composition in plants that can break the emulsion. The method of formulation of the demulsifier used is saponification is fundamental. Other methods currently available for demulsification can be broadly classified as chemical, electrical and mechanical. In this paper, the first experiment was carried out without any emulsion breaker. This was to certify that there was no natural demulsifier available in the crude oil. The second experiment was carried out using surphuric acid (H2S04) as demulsifier. There was little separation of water from the emulsion. The third experiment was carried out using the local demulsifier that was formulated, which show a high level of water separation from the oil emulsion. The results indicated that there is better level of separation when using local demulsifier than sulphuric acid. Also the density of crude oil emulsion before local demulsifier was added are 1.086 for BET-SCS and 0.982 for OREDO-4ST and after the local demulsifier was added, the density of crude oil increased to 1.141 for BET-SCS and 1.053 for OREDO-4ST. The research is fundamental to local content development, policy formulation and quality decisionmaking driven by adequate and verifiable data for sustainable development.
African Journal of Engineering and Environment Research Vol.6(2) 2024, 2024
The current study uses various approaches to assess the levels and possibly identify the source o... more The current study uses various approaches to assess the levels and possibly identify the source of atmospheric air pollutants in ambient air within designated areas of Port Harcourt metropolitan city of Rivers state. The pollutants of interest were particulate matters (PM2.5 and PM10), NO2, SO2, CO, CO2 O3, CH4, and NH3. The concentrations of air pollutants were evaluated using in-situ portable aeroqual gas detector and particulate matter counter. The source identification was carried out using principal component analysis (PCA). The average value for air pollutants in Port Harcourt zone were as follows: PM2.
African Journal of Engineering and Environment Research Vol.6(2) 2024, 2024
Traits changes in Planktonic Foraminiferal during the Palaeocene-Eocene Thermal Maximum (PETM) at... more Traits changes in Planktonic Foraminiferal during the Palaeocene-Eocene Thermal Maximum (PETM) at ODP Site 1265A, Walvis Ridge, SE Atlantic Ocean.
African Journal of Engineering and Environment Research Vol.6(2) 2024, 2024
The quest for continuous managing our operating plants systems to achieve a greateroutput optimiz... more The quest for continuous managing our operating plants systems to achieve a greateroutput optimization of process operation and systems maximization, the need for researches on quality mitigation of unforeseen system operation faults. Several research studies have been conducted over the years using several methods to mitigate the system-faults that may occur. However, the methods adopted in this study are: risk assessment framework, determination of risk level and analysis of data. The Maiduguri depot plant is a vital component of the NorthEast regional petroleum distribution network. Unfortunately, it faces distinctive challenges concerning of illoperations that requires the determination of acceptable risk levels for its pipeline and operations. Other challenges encompass geographical vulnerability, security threats, operational significance, regulatory compliance, and data limitations. In summary, the comprehensive risk assessment of Maiduguri Refinery Depot's pipeline systems has provided valuable insights into the varying risk levels associated with each segment. The findings indicate that Segment 2 poses a high risk due to a combination of elevated probability and severe consequences, necessitating immediate attention and targeted risk mitigation efforts. On the other hand, Segments 1 and 3 align with acceptable risk criteria, reflecting relatively lower likelihoods and less severe consequences. The incident frequency and severity rates further underscore the importance of a nuanced approach to risk management, tailored to the specific characteristics of each segment. These results align with existing studies as seen in the open literatures.
African Journal of Engineering and Environment Research Vol.6(2) 2024, 2024
Knowledge of the concentration of inhibitors in the flowline is necessary for operators
to deci... more Knowledge of the concentration of inhibitors in the flowline is necessary for operators
to decide on how much more chemical inhibitors to inject to keep the flowline safe. A
common flow assurance strategy of applying excessive dosages of an inhibitor to
minimize the risk of pipeline blockage due to hydrate formation often results in more
cost and severe impact on the environment. Current research interest is in chemical
methods that require the optimum chemical dosage that will be just enough to keep
the system safe from hydrate formation using knowledge of inhibitor concentrations
in the flowline. One of the most efficient of the methods is the conductivity and
velocity (C-V) technique. However, the method lacks mathematical models to
interpret the correlation of variables in the experimental data. It also does not have a
model that can be used as a predictor of new results. This work presents a second-
degree regression predictive model equation as the formulation approach for
mathematical models (MM) of electrical conductivity and velocity as a function of
inhibitor concentrations, salt concentrations, and temperature, leveraging on the
relationships of experimental parameters in the existing C-V method. Furthermore, an
artificial neural network (ANN) model is developed and trained to predict inhibitor
concentrations. To achieve all these, the study generated experimental data by
carrying out series of laboratory works to determine salt and inhibitor concentrations
in at varying temperatures using the conductivity-velocity (C-V) method. From the
results, apart from the solution containing 30.0 wt% Mono Ethylene Glycol (MEG)
and 5.0 wt% NaCl that has slightly larger deviations of – 0.7 and – 0.9 for MM and
ANN respectively due to MEG inhibitor concentrations that were beyond the range of
the training data, mathematical models and the ANN model generally agreed with
experimental measurements in determining inhibitor concentrations.
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Papers by African Journal of Engineering and Environment Research
to decide on how much more chemical inhibitors to inject to keep the flowline safe. A
common flow assurance strategy of applying excessive dosages of an inhibitor to
minimize the risk of pipeline blockage due to hydrate formation often results in more
cost and severe impact on the environment. Current research interest is in chemical
methods that require the optimum chemical dosage that will be just enough to keep
the system safe from hydrate formation using knowledge of inhibitor concentrations
in the flowline. One of the most efficient of the methods is the conductivity and
velocity (C-V) technique. However, the method lacks mathematical models to
interpret the correlation of variables in the experimental data. It also does not have a
model that can be used as a predictor of new results. This work presents a second-
degree regression predictive model equation as the formulation approach for
mathematical models (MM) of electrical conductivity and velocity as a function of
inhibitor concentrations, salt concentrations, and temperature, leveraging on the
relationships of experimental parameters in the existing C-V method. Furthermore, an
artificial neural network (ANN) model is developed and trained to predict inhibitor
concentrations. To achieve all these, the study generated experimental data by
carrying out series of laboratory works to determine salt and inhibitor concentrations
in at varying temperatures using the conductivity-velocity (C-V) method. From the
results, apart from the solution containing 30.0 wt% Mono Ethylene Glycol (MEG)
and 5.0 wt% NaCl that has slightly larger deviations of – 0.7 and – 0.9 for MM and
ANN respectively due to MEG inhibitor concentrations that were beyond the range of
the training data, mathematical models and the ANN model generally agreed with
experimental measurements in determining inhibitor concentrations.