Journal of Innovative Research in Engineering and Sciences
Journal of Innovative Research in Engineering and Science (JOIRES) is an international, peer-reviewed, open access journal that publishes the high quality research in the field of Applied Sciences and Engineering Technologies. It is an important forum for academics, researchers and industry practitioners to present latest developments, theoretical insights and solutions to the most pressing challenges of the present-day.
Comparative Proximate Composition of Leaves and Stems of Artocarpus heterophyllus, Artocarpus altilis, and Artocarpus camansi
This study compared the proximate and mineral compositions of Artocarpus heterophyllus, Artocarpus altilis, and Artocarpus camansi. Fresh leaf and stem samples were collected from Aguluezechukwu, Anambra State, Nigeria, and authenticated by a plant taxonomist. Proximate analyses were conducted using standard AOAC (2016) methods for moisture, crude protein, ash, crude fibre, fat, carbohydrate, and dry matter determination. Mineral composition was assessed using Atomic Absorption Spectrophotometry following acid digestion. Data obtained were analyzed using Analysis of Variance (ANOVA) and Duncan’s Multiple Range Test at 5% significance level. Results revealed no significant differences (p>0.05) in most proximate parameters among the three species, although variations in mean values were observed. Artocarpus altilis exhibited comparatively higher fibre, carbohydrate, and ash contents, while A. camansi showed slightly higher moisture and fat contents in some parameters. Mineral analysis indicated that leaves generally contained higher concentrations of calcium, phosphorus, potassium, and sodium, whereas stems showed relatively higher magnesium levels. In conclusion, while these Artocarpus species share similar proximate profiles, their distinct mineral distributions highlight their specific nutritional value, suggesting they are viable resources for dietary supplementation and therapeutic applications in Nigeria.
Optimisation of an industrial high-temperature thermal shell-and-tube heat exchanger: a petrochemical case study
This study presents computational fluid dynamics (CFD) evaluation of Syltherm 800 and ethylene glycol as shell-side working fluids in a shell-and-tube heat exchanger (STHE) used for feedstock preheating in a petrochemical facility. The major objective was to enhance thermal efficiency while minimizing pressure drop and pumping power in energy-intensive operations at Indorama Eleme Petrochemicals Company Limited, Nigeria as a case study. A three-dimensional steady-state CFD model was developed in COMSOL multiphysics using the Navier–Stokes and energy equations under turbulent flow conditions. Ethylene glycol at 120°C was used as the baseline case and compared with Syltherm 800 at 120°C, 300°C, and 350°C. Results showed that Syltherm 800 significantly improved the thermal performance at elevated temperatures; while ethylene glycol at 120°C produced a total heat flux of approximately 9.1kW with an inlet pressure of 3,197Pa, Syltherm 800 at 350°C achieved a heat flux of 30.996kW and reduced inlet pressure to 1,676Pa. Further, the tube-side outlet water temperature increased from 35.28°C (ethylene glycol) to 44.03°C (Syltherm 800 at 350°C). The findings revealed that Syltherm 800 enhances heat transfer while reducing hydraulic resistance. The research work established the required fluid material to be used for optimal performance of the case studied industrial heat exchangers for high-temperature petrochemical applications.
Development of Sb2S3 as a double absorber layer with Sb2Se3 by Simple and Low Cost Chemical Bath Deposition Technique for Solar Cell Applications
Antimony sulfide (Sb2S3) has been explored for its potential in optoelectronic applications. It was synthesized using a low-cost and facale chemical bath deposition (CBD) method. The resulting material showed an orange color, consistent with previous reports. This study focused on examining how varying concentrations of sodium thiosulphate (Na2S2O3) affect the optical and morphological characteristics of Sb2S3. Additionally, the impact of annealing on these properties was also analyzed. Comprehensive characterization was carried out to assess structural, optical, and surface features. X-ray diffraction (XRD) results indicated that the as-deposited Sb2S3 films were amorphous. However, annealing at 200 °C enhanced the crystallinity of the material. Optically, the film deposited with a 2.0 M concentration showed 99% absorption in the blue line (450–495 nm) of the visible spectrum, while the 2.5 M sample exhibited similar absorption in the UV range. An increase in Na2S2O3 concentration corresponds to a gradual rise in the energy bandgap. Atomic force microscopy (AFM) revealed that root mean square (RMS) roughness consistently decreased with increasing annealing temperature. However, changes in sodium thiosulfate concentration did not produce a clear trend in surface morphology. The surface roughness varied across different concentrations. Scanning electron microscopy (SEM) images showed the formation of large, mushroom-shaped grains around 8 µm in size, which reduced with annealing. The strong light absorption in both visible and ultraviolet regions suggests that Sb2S3 is a promising material for solar cell absorber layers and photodetector applications.
Multi-Factorial Prediction of Mild Steel Exposure Time during Its Corrosion Inhibitionwith Hibiscus Sabdariffa Leaf Extract in 0.5M H2SO4
This paper evaluates the exposure time of mild steel (which corroded in sulphur acid solution while in contact with an inhibitor- Hibiscus Sabdriffa) based on pre-determined penetration depth and corrosion rate. The analysis carried out was using a derived empirical model; θ = exp(Ϧ(ẟγξ-1) - ẞ). Mild steel was submerged in 0.5M H2SO4 containing sabdariffa leaf extract which serves to inhibit corrosion of the steel. In the course of the model derivation, following experimentals, the applied range of values of the process parameters: exposure time, penetration depth and corrosion rate were 0.00548 – 0.011 hrs, 0.0047 – 1.0121mm, 0.8638-0.1027mm/yr respectively. The validity of the model is strongly rooted on the core model structure; lnθ + ẞ ≈ Ϧ(ẟγξ-1). The model-predicted results agree with previous research on the direct relationship between the corrosion rate & penetration rate and exposure time, while inhibitor concentration is constant. The standard error incurred in predicting the model based exposure time relative to the experimental results was 0.0004%, implying over 99% model confidence level. The exposure times per unit penetration depth and corrosion rate for experimental & model-predicted results were evaluated as: 0.7459 & 0.9297 yr mm-1 and 0.0231 & 0.0288 (yr)2 mm-1 respectively. Furthermore, the correlations between these highlighted parameters, as evaluated from both results were all > 0.97. The overall maximum deviation of model-predicted mild steel exposure time from experimental results was 9.09%.
Response Evaluation of Mild Steel Corrosion Rate in H2SO4 to the Synegistic Influenceof Exposure Time and Steel Weight Loss
The response of mild steel corrosion rate in 0.5M H2SO4 (while in contact with an indicator- Hibiscus Sabdariffa) to the synergistic influence of exposure time and weight loss of the steel has been successfully evaluated. The predictive evaluation was carried out using a derived empirical model; ξ = Ϧ (- ẞɤ2 + Ҽɤ - Nτ2 + Фτ+ Ǧ) Prior to derivation of the empirical model, mild steel was submerged in 0.5M H2SO4 containing an inhibitor; sabdariffa leaf extract which strived to resist corrosion of the steel. In the course of the model derivation, applied ranges of values of the process parameters: corrosion rate, exposure time and weight loss were 0.6916 – 0.7086 mm/yr, 0.00548 – 0.0164yr and 0.0799 -0.2456g respectively. Results generated were based on weight-loss method. The validity of the derived model is strongly rooted on the core model structure; (ξ/Ϧ) – Ǧ ≈ - ẞɤ2 + Ҽɤ - Nτ2 + Фτ.. The model-predicted results agree with previous research on the polynomial relationship between the corrosion rate and exposure time & mild steel weight loss, while inhibitor concentration is constant. The standard error associating model prediction of corrosion rate, relative to the experimental results was 0.0076%, implying over 99% model confidence level. The corrosion penetration depth on the mild steel per unit exposure time for experimental & model-predicted results were evaluated as: 4.406 x 10-4 mm and 4.509 x 10-4 mm, while corrosion rate per unit weight loss of the steel were 1.304 and 1.335mm/yr/g respectively. Evaluated correlations between corrosion rate and exposure time & weight loss of steel, as obtained from both results were all > 0.96. Deviational and statistical analyses of evaluated results indicate that the overall maximum discrepancy of model-predicted mild steel corrosion rate from experimental results was 2.4%.
Process performance enhancement in cable manufacturing based on the synergetic integration of LSS-DMAIC approach and knowledge capturing mechanisms
In cable manufacturing, product quality is essential and variation in product is a critical issue, but in most cases results from solutions to cable defects identified during process improvement projects are not sustained. This anomaly is likened to the outsourcing of improvement functions to external professionals most of the time and also due to absence of knowledge-based solution, robust enough to solve most of the real-life quality problems that prevails in a dynamic cable manufacturing environment. Hence there exists a need for an efficient deployment strategy applicable in cable manufacturing that will aid organizations in their improvement studies to solve real life problems as well as to become a knowledgeable organization. The goal of this study is to improve cable manufacturing process performance by utilizing the complementary ideas of Knowledge Management (KM) and Lean Six Sigma-DMAIC (LSS-DMAIC). The conceptualized model also provided an environment for the development of employee capability while preventing excessive financial losses for the cable manufacturing sector through the careful identification of knowledge domains, retention of previously learned information, and the development of strong social capital within the organization. Finally, this study added a type of integration strategy that would help process improvement practitioners in cable manufacturing companies to the body of existing process improvement studies. It focused on the complementary benefits of these two different disciplines, "LSS and KM," which have been rarely discussed in Nigerian process improvement studies
Process Parameters Optimization in Plastic Manufacturing Industry using Machine Learning
This research is aimed at optimizing the process parameters in plastic manufacturing industry using machine learning. Taguchi L27 orthogonal array was employed in the design of experiments and small-the-better signal to noise ratio was used in the analysis of volumetric shrinkage variation (VSV) of the plastic tray. The analysis of variance (ANOVA) was used to determine the significant parameters affecting VSV of the product. Artificial neural network (ANN) was employed in optimization of the machine process parameters settings and prediction of the quality characteristic. The results showed that the optimal VSV occurred at mould temperature of 440C, melt temperature of 2100C, holding pressure of 41MPa, injection time of 6 seconds, and packing time of 8 seconds. The ANOVA results showed that the mould temperature was the dominant factor influencing VSV of the plastic product. The optimization of the machine process parameters and quality characteristic using ANN model reduced the shrinkage value of the product by 29.9%. This study concludes that the optimal process parameters settings determined using ANN are better than the settings being used in the industry.
Development of Hybrid Bamboo-Plantain Fibre Composite for Ship Hulls and Submarines
Marine composites require a combination of high strength, low weight, and durability to withstand the harsh environments. In light of the traditional glass and carbon fibre composites present sustainability challenges, hybrid natural fibre composites hold promise for environmental benefits. However, their properties need optimization for maritime applications. This study focuses on developing a hybrid bamboo-plantain fibre-reinforced polyester composite, employing response surface methodology (RSM) to enhance mechanical performance and durability. Alkaline-treated bamboo and plantain fibres were incorporated into unsaturated polyester resin with varying orientations, stress ratios, and volume fractions, following a custom optimal design within RSM. The resulting specimens underwent tests, including tensile, impact, absorption, fatigue, and buckling assessments. Statistical analyses demonstrated that fiber orientation, volume fraction, and stress ratio markedly influence the composite's properties. The RSM findings identified the optimal configurations for fiber orientation (51.22), volume fraction (56.14), stress ratio (0.5), as well as impact testing, ultimate tensile strength, water absorption, oil absorption, fatigue strength, and buckling load, quantified as19.81, 159.93, 2.87, 2.32, 150.46 and 110.49, respectively. Overall, RSM successfully optimised the hybrid composite, highlighting the potential of natural fibre materials in shipbuilding through systematic material design strategies.
Small and Large Deflections in Slabs and Cantilevers Using Isogeometric and Finite Element Analysis Approach: Implications for Buildings under Erosion Effects
In this study, the deflection behaviour of structural elements was reviewed in detail in order to ascertain the possible failure behaviour of structures in erosion prone regions of Anambra State. The study was approached using isogeometric and finite element analysis using MATLAB and C++ programming language. The study focused more on deflection sensitive structural components such as plates and cantilevers. Using isogeometric analysis (IGA), the small deflection of a 6m x 6m clamped plate subjected to a serviceability pressure load was found to be 0.0627% more than the exact solution. IGA gave better result than finite element analysis carried out using StaadPro software (matrix size: 20 x 20) which was 1.1173% higher than the exact solution. Using Mindlin plate theory (incorporating shear deformation), IGA results were 0.1856% higher than finite element analysis result. On considering the large deformation of the square plate element at serviceability limit state at 100 iteration steps, the results show that the maximum deflection was 1.613mm, exactly the same with small deflection theory. At ultimate limit state (failure load), the result from large deflection analysis increased to 2.375mm (32.084% increase) at 100 iteration steps.
Review of Oil and Gas Composite Piping System
Continued increase in the use of vessels for storage, industrial processing, and power generation under unusual conditions of pressure, temperature, and environment has given special emphasis to analytical and environmental methods for determining their operating stresses. Creeps, fracture, fatigue, explosion, vibration, expansion, buckling loads, etc constitute factors known to cause some form of stresses and deformations or failure in composite material vessels used in oil and gas industry. Good knowledge of the nature and magnitude of these stresses enables provision of the adequate methods for their prevention and control. The study aimed at modeling the wall thickness of an oil pipeline (pressurized cylindrical vessels) used in transferring oil from one location to another. In doing so, a review of some published works on such factors as creeps, fracture, fatigue failure, expansion, buckling loads, etc was also made. A liquid flow problem was formulated and solved using a number of the existing design failure theories used in the design of oil and gas piping systems. The solved problem shows vividly how the wall thickness of an oil pipeline under fluid pressure can be determined and selected from among the existing commercial standard pipe sizes. It is hoped that this work will answer some of the questions asked by engineering students during lectures on theories and design of pressure vessels.
Characterization of Plantain Fiber Reinforced High Density Polyethylene Composite for Application in Design of Auto Body Fenders
High density polyethylene composite reinforced with natural plantain fiber was produced using injection moulding technique. The production process utilized the popular L18 Taguchi experimental design which allowed for investigating the effects of the major production variables (the machine parameters) such as; barrel(melt) temperature, mold temperature, injection pressure, holding pressure, back pressure, clamping force and shaft speed in the final mechanical property of the product. Moreover, the need to use improved fiber volume fraction/particle size and appropriate compactibilizer mass was verified. The various mechanical tests conducted on the new composite material reveal that fiber volume fraction of 0.1, particle size of 75μm and compactibilizer mass of 0.00024kg yields a high quality composite material with improved mechanical properties suitable for auto body fender application. The Taguchi robust design technique was applied for "the greater the better" to obtain the highest signal-to-noise ratio (SNratio) for quality characteristics (strengths) in the determination of optimum factor levels. The improved PFRHDPEC was found to have optimum tensile strength of 87.44MPa , yield strength of 76.6MPa , Flexural strength of 77.03J, Rockwell Hardness strength of 756.99, Impact strength of 16.21J and density of 993kg/m3 . The result shows that the auto body fender produced based on compactibilized PFRHDPEC has an advantage of reduced density compared to that of steel and alternative composite materials
Response Surface Optimization of the Impact Strength of Plantain Fiber Reinforced Polyester for Application in Auto Body Works
The impact strength of plantain fiber reinforced polyester composites (PFRP) was evaluated to assess the possibility of using it as a new material in engineering applications. The study considered the controlling factors (notch tip radius (A) and notch depth (B)) of different reinforcement combinations in the determination of impact strength of the composites. This property was determined for plantain empty fruit bunch (PEFBF) and plantain pseudo stem (PPS). Impact tests were conducted on the replicated samples of PEFB fiber reinforced polyester composite and PPS fiber reinforced polyester respectively using Archimedes principles in each case to determine the volume fraction of fibers. To obtain the optimum properties being investigated, Charpy impact tester was used to establish the actual control factor levels needed to optimize the mechanical properties being investigated. These control factor levels were then applied to optimize the mechanical properties of plantain fiber composites using response surface methodology (RSM) of Design – Expert 8 software. The impact strength of plantain fiber reinforced polyester was evaluated as 167.851 KJ/m2 for optimum performance.
Optimal Design for Flexural Strength of Plantain Fibers Reinforced Polyester Matrix
This study considered the controlling factors, volume fraction of fibers (A), aspect ratio of fibers (B) and fibers orientation (C) in the determination of flexural strength of plantain fibers reinforced polyester composites (PFRP). These properties were determined for plantain empty fruit bunch fibers reinforced polyester matrix (PEFBFRP) and plantain pseudo stem fibers reinforced polyester (PPSFRP). Flexural tests were conducted on the replicated samples of PEFBFRP and PPSFRP respectively using Archimedes principles in each case to determine the volume fraction of fibers. To obtain the optimum properties being investigated for the results of the mechanical tests obtained using a Monsanto tensometer were used to establish the control factor levels needed to optimize the mechanical properties being investigated. The optimum values of the control factors were established for empty fruit bunch composites and for pseudo stem fiber composite. The empty fruit bunch fiber reinforced polyester matrix composite has the maximum flexural strength of 42.40MPa, while the pseudo stem plantain fiber reinforced matrix composite has the maximum flexural strength of 41.16MPa. The finite element analysis showed that the composite sample subjected to 48.228MPa will deflect 14.569mm within its elastic limit while the use of FTIR spectroscopy confirms that PEFPRFP is stronger than PPSFRP.
Factors Affecting Dephosphorization of Agbaja Iron Ore (Kogi State), Nigeria
The purpose of this research work is to determine the optimal factor combinations for dephosphorization of a Nigerian Agbaja iron deposit –the largest inferred deposit of about 1.250 billion tones. The process parameters used in dephosphorization include concentration, particle size and time dwell. Because of sequential experimentation, RSM [Response Surface Methodology] of central composite design (CCD) as used in estimating response surface of second order regression equation. The RSM is widely used as an optimization, development, and improvement technique for processes based on the use of factorial designs—that is, those in which the response variable is measured for all the possible combinations of the levels chosen of the factors. The main effect of a factor is defined as the variation in response caused by a change in the level of the factor considered, when the other ones are kept constant. The results generated from the experiment indicated that optimum conditions of dephosphorization of about ≤0.05 were obtainable at concentrations of 0.6M, dwell time of 35mins and particle size of 0.27mm respectively
Common Types of Anopheles Gambiae Breeding Habitats in North Western Nigeria
Malaria constitutes a major public health concern in Nigeria, where it is exacerbated by very high vectorial density due to favourable breeding conditions. This study investigates whether the links between physicochemical characteristics of An. gambiae breeding habitats and their productivity (larval density) can be used to finger print and define mosquito breeding habitats based on three most common human related activities (residential, agricultural and petrochemical) in Northern Nigeria. The characteristics and levels of 13 physicochemical environmental factors and breeding sites productivity were determined in three common mosquito breeding habitats (designated as study zones). Biological oxygen demand (BOD), total dissolved solids (TDS) and all the six chemical factors examined differed significantly (p<0.05) across the three study zones. Specifically sulphates, phosphates, nitrites and nitrates levels were significantly higher in the agricultural areas, while carbon content and oil and grease were significantly higher in the petrochemical laden breeding ecologies. An. gambiae larval density was significantly higher in domestic environments compared to the other two studied zones and correlated positively with BOD and transparency (p<0.05). Contrarily, the larval density correlated negatively with pH, temperature and all the chemical factors (p<0.05). An. gambiae breeding sites productivity was significantly affected by the levels and characteristics of some physicochemical environmental factors, which also weightily impacted to segregate and distinctly define the major human related activities taking place within and/or around the sites. This could pose a serious but different challenge to environmental management and insecticides based approaches to malaria vector control in Nigeria.
Usability of the Colour Coded Resistor Identification tool for students of Tertiary institution
Functionalities of electronic and electrical designs and experimentations are based not only on accurate calculation, but also on the choice of correct components. However, the identification of passive electrical components is one of the major problems facing the students of tertiary institutions during design implementation and experimental works. This work is the development and testing of a visualization tool that can easily be applied to enhance the identification of the values of coded resistors during laboratory experiments and electrical design implementation. An algorithm was developed based on the standard British colour codes, and was coded using Microsoft Visual Basic 2010 programming language. Sample cases were considered to test the usability of the developed algorithm. To validate the usefulness of the tool, usability tests were carried out by sequentially assigning sixteen samples of coded resistors for identification to part III, part IV and part V students of electrical and electronic students. The results showed that when identifying without using the tool, only 19% of the students identified resistors values correctly, whereas 96% of the students identified them correctly when identification tool was used, indicating the usefulness of the tool to students of tertiary institution engaging in electrical laboratory and design works.
Structural Characteristics of Sandcrete Blocks Produced in South-East Nigeria
Blocks are indispensable materials predominantly used as walling units in the construction of shelter (which is one of the basic needs of man) and other infrastructures. Some of the problems faced in construction can be linked to this masonry unit, which is a major construction material. A survey was conducted of the various block moulding firms within south east Nigeria to determine the mode of production of blocks, mix ratios nature/quality of sand and the structural characteristics of the blocks. In this paper, the results obtained were compared with standard specifications. It was found out that most of the blocks produced are generally substandard. Block production practices in Nigeria should be looked into by the government. Quality control should be introduced to assist block producers to produce strong and durable blocks at minimal cost.
Construction and Installation of Solar Powered Borehole for a Primary Health Centre
The need for constant water supply cannot be over emphasized. This cannot be attained with our epileptic grid power supply while some rural areas have no grid power supply at all. In order to ensure constant water supply especially to remote areas without grid power supply, we must go for an alternative energy source to provide constant electrical power to the water pumping machine. The alternative energy source used in this work is the ever present renewable Solar Energy. In this installation, solar panels were used to harness the energy from the sun, CU200 controller to control the pumping mechanism and Grundfos SQFlex water pumping machine to pump out water from the borehole. The system is an automatic water pumping system which does not need an operator to control its ON/OFF state.
Analysis of Brands of Glibenclamide Tablets in Lagos Market
Glibenclamide is an oral antidiabetic drug which belongs to the second generation of sulfonulureas. It is an insulin secretagogue used in the treatment of type 2 diabetes mellitus. Use of substandard products may lead to poor blood glucose control and life threatening complications. The aim of this study was to analyze different brands of glibenclamidetablets for quality in terms of content of active ingredients and some physicochemical parameters. Nine brands of glibenclamide tablets were sourced from various pharmacy retail outlets in Lagos and subjected to chemical assay by HPLC method. Various physical tests including uniformity of weight, hardness, friability and disintegration time were also carried out. The results indicate that 78% of the samples show compliance with the British Pharmacopoeia (BP) standards for content of active ingredients. All the samples passed the tests for uniformity of weight and disintegration time but failure rate of 11% was recorded for both friability and tablet hardness tests. It is recommended that routine quality surveillance systems be established by drug regulatory bodies to monitor drug quality at all levels of the distribution chain to ensure product quality and consumer safety.
Optimisation of concrete mix cost using Scheffe’s simplex lattice theory
In order to obtain concrete which will meet a number of performance criteria simultaneously at minimum cost, it is necessary to carry out the optimization of concrete mixture design. In this work, the cost of concrete mixtures is optimised using Scheffe’s optimisation theory. The cost optimisation is based on current market prices of concrete components. In case of price fluctuations over time, the current prices of concrete component can be obtained by multiplying the base prices with a price fluctuation factor (PFF). The optimization model can be used to determine the cost of producing one cubic meter of concrete. Conversely, it can be used to obtain the concrete mix proportions that can be afforded by a specified amount of money. The model values were approximately equal to estimated values. The use of the optimisation model eliminated the arbitrary choice of concrete design mixes and its associated disadvantages. In addition, it yielded optimum concrete mixtures, which minimises costs and satisfies specific performance requirements.
E-Marketing for Nigeria Agricultural Products
One of the problems facing Agricultural farmers in Nigeria is how to market their products beyond their locality. Information technology tools have been tested and accepted widely and can be used to solve the problem of marketing faced by farmers. This paper explores the background of the study relating to agricultural practice and marketing of the agricultural products in Nigeria. It proposes the use of merchant to act as a middle-agent between the farmers and consumers for the marketing system. This paper explores the use of web application to market farm products which includes tubers, grains, and so on. An interface is provided on the web application to allow the customers select their preferred products to their carts and an invoice will be generated electronically based on the goods selected. Thereafter, a two-way payment is made available; online payment using e-transacts and local payment to the merchant account directly.
Analysis of Nigeria Power Generation Sustainability through Natural Gas Supply
The use of natural gas as a fuel in heat engines for the generation of electricity is a technology that has been for decades, which operates on the Brayton cycle principle. In a bid to meet the energy needs of Nigerians despite its unparallel gas potentials of about 187 TCF of proven gas reserves, Ughelli Power PLC was put under study. The study reveals that there was an uneven energy generation despite the large quantity of gas supplied. Nigeria’s total installed capacity is at 6000 MW with its present output at 3000MW. The study of Delta four power plants reveals an average consumption of 1,021,490,501.43 scf of gas indicating 82,461.24 MWH (178.1MW) energy generation. A total average power generation of 30.5% out of the installed capacity was found, resulting in 2.9% of National contribution. It is strongly recommended that Proper gas conservation practices should be enforced.
Discrete Vortex Modelling of Turbulent Flow in Two Dimensions
There has been growing need to characterize the turbulent flow through a simplified model. This paper reports the characterization of turbulent flow in two dimensions using discrete vortex modelling. The free surface flow in channel is considered as a case study. Appropriate flow charts and FORTRAN source codes were developed to solve the main governing equations of fluid flow. The Reynolds number which is the control parameter from 100,000 (experimental transition point) at an interval of 10,000 to 1,000,000 is used and the result is displayed using Microsoft Excel Graph. After the four stages of transition process due to Helmholtz instability, the turbulent region is reached, which is characterized by irregularity, low momentum diffusion, high momentum convection, and rapid variation of velocity. The result has shown that turbulent flow can be characterized with ease by using discrete vortex modelling.
Caffeine Content of Cocoa and Coffee Beverages in Lagos, Nigeria
This study determined the caffeine content of various brands of cocoa and coffee-based beverages in Lagos, Nigeria. Ten brands of these products were purchased from various shops in the Lagos metropolis. Caffeine was carefully extracted from each product and analyzed by ultraviolet/visible spectrophotometric methods. The results show that the caffeine content of the cocoa-based products ranged from 1.8 to 3.1 mg/g of product while classic and decaffeinated coffee contained 8.4 and 2.3 mg/g of product respectively. These amounts are considered low and safe for healthy adults when compared with established safety levels of the US Food and Drugs Administration. It was recommended that people who need caffeine restriction due to health conditions should choose products with lower caffeine contents. Also, since caffeine is an additive substance, manufacturers of caffeine-containing products should be required by regulation to indicate its presence and amounts on package labels for the information of the consuming public.
Project Economics as a Tool for Evaluation of Viability of Projects: A Case of Palm Oil Milling Plant
In this research work, a case study of a proposed palm oil milling plant by an entrepreneur is looked into. This is with a view to ensuring its Viability, and also delving into the Risk, Uncertainty and Sensitivity Analysis of vital parameters. At the end of all analyses, the entrepreneur is well guided to take a decision on whether or not to commit his or her scarce resources. Basic engineering economy methods for project evaluation are highlighted. With the added information from the sensitivity analysis the investor would be better informed about critical factor and therefore could take appropriate actions.
Modelling and Real Time Implementation of Digital Pi Controller for a Non Linear Process
In Process industries, control of process parameters for a nonlinear process is one of the important issues identified in literature. The nonlinear process considered for modeling is spherical tank liquid level system. Control of liquid level in a spherical tank is nonlinear due to the variation in the area of cross section of the level system with change in shape. System identification of this nonlinear process is done using black box model, which is identified to be nonlinear and approximated to be first order plus dead time model. Here the Digital PI controller is designed using Ziegler Nicholas Tuning rule. The real time implementation of the process is designed and implemented in MATLAB using VMAT-01 Data Acquisition Module.
Managing Trans-Regional Water Transfer in Dry African Countries to Mitigate Shortages
The deficiency of water resources is limiting directly and severely the socioeconomic development and ecological environmental protection in the Internal Drainage basin (IDB) in the central part of Tanzania which is considered to be semi-arid region. Due to the regional differences in water availability a revised setting of in country water distribution is required. The objective of the work described here within is to determine the least-cost solution for a national water transportation system among the regions, simultaneously meeting the water delivery requirements in the IDB and complying with all other relevant regulatory criteria. The principal of optimal water transportation from eight administrative source basins to the IDB by cost minimization has been implemented. The results obtained by using 70% level of annual renewable water for Environment Water Requirements (EWR) suggest that excess annual renewable water resources from source basins is sufficient to supply the IDB. Transportation constraints imposed in the water management model limits some of the basins to be considered as preferred water sources. On the basis of the modeling results, Lake Tanganyika basin, Lake Rukwa basin and Wami/Ruvu river basins (all are in Tanzania) have been identified as reasonably preferred water sources. Pangani basin in the north-eastern part of Tanzania is under water shortage, water withdrawal from the Pangani basin would further damage the Pangani river ecology and water environment. The optimum total costs (operation costs, capital investments and maintenance of the concrete pipeline) range between 0.69 and 1.37 US $/m3.
Kinetic, equilibrium and thermodynamic studies of the biosorption of Pb(II), Cd(II) and Cr(III) by neem leaf
The biosorption of Pb(II), Cd(II) and Cr(III) by Neem (Azadirachta indica) leaf is reported in this work. The effects of solution pH, contact time, initial metal ion concentration and temperature on the biosorption of the metal ions were investigated. Optimum pH for each metal ion was obtained at pH 4. The kinetic study shows that the biosorption of the metal ions followed both pseudo-second-order and Elovich kinetic models. The sorption was analysed with Freundlich and Langmuir isotherm models and in each case the Freundlich model appears to have better regression coefficients than the Langmuir. Thermodynamically, the biosorption of Pb(II) and Cr(III) were found to be endothermic while that of Cd(II) was exothermic. Similarly positive change in entropy was observed for each of Pb(II) and Cr(III) while negative change in entropy was observed for Cd(II).
A comparative Study on the Design and Characteristic Performances of DICON made Guns in Nigeria
This paper provides insights into the designs and characteristic performances of different types of guns made by the Defence Industries Corporation of Nigeria (DICON), through comparative analysis of their data facts as obtained from surveys at the company with corresponding similar gun types designed and produced by reputable manufacturers in other nations of the world. Generally, the guns produced by the corporation have been found to be of high and comparable performance capabilities with the best similar types elsewhere in the world, inspite of design variations between them.
Production and Testing of Biodegradable Grease from Black-Date (Canarium schweinfurthii) Oil
This work focuses on the production and testing of biodegradable grease from Black-date oil. The production was carried out by extracting the oil from black-date seed with solvent extraction using n-hexane; hydrolyzing the oil extract as a mixture of the base oil, thickener (calcium hydroxide), stearic acid and additives to form solid grease. Tests were carried out to determine the quality of the biodegradable grease produced. Work ability, dropping point and biodegradability were also conducted. Oando and Texaco conventional greases were used as control and standards. The production condition, measurement standards and results were: water temperature for removing black-date flesh from the seed (600C -700C); and temperature for the productions of grease were 1000C, 1700C and 2100C. The BOD test result were within the acceptable range of 4.0 – 8.0 and the cone penetration of grease (consistency) result was of the ASTM D217 – IP50 standard with the highest produced grease dropping point close to that of Oando grease. This work therefore has added to the list of feedstocks for bio-based lubricants which can be of use both in terrestrial and aquatic environments for industrial and other applications.