FACULTY OF ENGINEERING

Welding is a vital manufacturing process used in several industries, including aerospace, automotive, and construction. However, residual and induced stresses that develop during welding due to rapid heating and cooling cycles often affect the structural integrity of the weldment thereby reducing the integrity of the structure. The study investigates the application of Artificial Neural Networks (ANN) in predicting the actual maximum stress in Tungsten Inert Gas (TIG) weldments and develop a predictive model capable of accurately estimating the actual maximum stress in TIG welded joints based on key process parameters such as welding current, voltage, and gas flow rate. Twenty (20) experimental runs as generated by the Central Composite Design (CCD) was used to carry out TIG welding on mild steel plates. A Universal Stress Testing Machine was used to measure the actual maximum stress in the weldment and the result was recorded for each experimental run. This experimental result was then analyzed using ANN. ANN trained trained the neural network with fourteen (14) of the observations and use three for network validation and another three for network testing. The best validation performance value of 80.6689 was observed at epoch 5 with an overall performance value of 0.96864. ANN predicted response values was compared with the experimental result and it showed a meritorious correlation with the experimental result trend. The results revealed that the developed ANN model achieved high prediction accuracy with minimal error, confirming its capability to learn and represent the complex nonlinear relationship between the welding input parameters and the resulting actual maximum stress

The global edible oil industry is dominated by palm oil due to its high yield, versatility, and economic importance. Although Nigeria was once the world’s leading producer of palm oil, its current contribution to global output is less than 2%, largely due to outdated and inefficient processing technologies, particularly at the small-scale production level. One of the critical stages affected is the clarification process, which significantly influences the quality of the final product.

This study focuses on the design and fabrication of an improved diesel-powered palm oil clarifier specifically intended for small-scale producers. The machine is developed to enhance processing efficiency, improve product quality, and reduce the labor-intensive and rudimentary methods currently in use. The design addresses key challenges in the clarification stage by introducing a more effective separation process, thereby minimizing impurities and improving oil yield and quality.

The proposed system is tailored to meet the needs of rural and small-scale oil palm farmers who lack access to advanced processing technologies. By improving the efficiency of palm oil clarification, the machine is expected to contribute to increased productivity, better product quality, and enhanced economic returns for local producers. The study concludes that the adoption of improved mechanized clarification technology is essential for revitalizing Nigeria’s palm oil sector and strengthening its competitiveness in the global market.

The main objective of this machine is to remove the coconut shell and to eliminate the skilled labour involved in de-husking. The coconut outer shell is a fibrous husk one to two inches thick. This paper deals with the design and fabrication of Electric motor operated coconut de-husking machine. This project is aimed at producing an efficient and more economical machine for coconut industry. The coconut is known for its great versatility as seen in many domestic, commercial, and industrial uses of its different parts. Coconuts are different from any other fruits because they contain large quantity of tender and when immature they are known as tender-nuts or jelly-nuts and may be harvested for drinking. When they mature they still contain some water and can be used as seed nuts or processed to give oil from the kernel, charcoal from hard shell and coir from fibrous husk.
One traditional method used for coconut de-husking is using a machete. This is done by using human energy. This method is risky and tedious and yet requires skills. Hence an alternative is suggested in our project which reduces time involved in coconut de-husking and human effort. Depending upon the survey different sizes of coconut are determined. The machine is designed to accommodate different sizes of the coconut that are cultivated anywhere in the world.

Process parameters have been known to determine the quality of weldments in welding operations. Therefore the process parameters have to be manipulated to determine the desirable quality of the weldment. In doing this, the Taguchi method was applied to optimize these process parameters. The response obtained from the welding operation was the Impact strength of the weldments. From using the Taguchi method, it was derived that the optimum process parameters is A3,B1,C3. The analysis of variance was computed to determine the level of contribution of each of the process parameter to the quality level of the weldment.
It was investigated that voltage contributed most having a total of 14.42% of the quality level of the weldment, followed by the welding current, with a value of 7.94% and gas flow rate being the least with a contribution of 2.04%. A confirmation test was carried out to validate the inference that A3,B1,C3 is the optimum process parameters. The signal to noise ratio of the existing process parameters of A2 B3, C1 was determined to be 40.3997dB, whereas, the optimum welding process has a signal to noise ratio of 42.8796 dB. This shows that there is an improvement of 2.4799 dB of the optimum process parameters over the existing one. The Impact Energy of the weldment produced by the welding operation made by using the optimum process parameters has 12 J more than the Impact Energy obtained from the weldment made by using the existing process parameters.
In this study, the Taguchi method was useful in improving the quality of weldment made by applying the optimum process parameters obtained.

Climate change poses significant threats to the built environment through rising temperatures, altered precipitation patterns, and increased frequency of extreme weather events. This study investigated the impact of climate change on the durability of building materials commonly used in Nigeria. A comprehensive analysis of 60 years of meteorological data (1965-2024) from the Nigerian Meteorological Agency (NIMET) was conducted across Nigeria's three climatic zones. The data was divided into two 30-year periods Historical Period 1 (HP1: 1965-1994) and Historical Period 2 (HP2: 1995-2024) to identify climatic trends and their implications for concrete, steel, timber, and masonry materials. The methodology employed secondary data collection and literature review, analyzing four key climatic parameters: mean annual temperature, total annual rainfall, mean annual sunshine hours, and mean annual wind speed. Comparative analysis revealed significant environmental shifts, with Southern Nigeria experiencing the most severe changes including temperature increases of +1.0°C, rainfall increases of +298mm, and reductions in both sunshine hours (-0.6 hr/day) and wind speed (-0.6 m/s).Results demonstrated that all building materials face substantially accelerated degradation under current conditions. Concrete experiences enhanced carbonation and chloride penetration with 2030% service life reductions. Steel reinforcement shows 30-40% service life reduction in coastal environments due to intensified corrosion. Timber faces the highest vulnerability with potential 40-50% service life reductions from enhanced fungal decay and increased termite activity. Porous masonry units experience severe efflorescence and progressive strength loss, resulting in 20-40% service life reductions. The study revealed synergistic effects where combined climatic changes produce deterioration exceeding individual impacts, with Southern Nigeria facing the most aggressive conditions. The study concludes that traditional construction practices based on historical climate data are inadequate for current conditions. Recommendations include immediate revision of building codes and material specifications, adoption of climate-resilient materials and enhanced protective systems, implementation of climate-responsive design approaches, and intensified maintenance programs for existing structures. These findings provide critical insights for stakeholders to enhance building resilience and ensure the sustainability and safety of Nigeria's built environment.

This research investigates the suitability of cow bone ash (CBA) as a partial replacement for ordinary Portland cement (OPC) in concrete production, with the aim of reducing cement consumption, lowering environmental impact, and promoting sustainable waste management practices in Nigeria. Cow bones, which constitute a major agricultural waste product, were processed into ash through controlled calcination and evaluated for their potential pozzolanic contribution in concrete. The study focused on assessing the effects of varying percentages of CBA on the fresh and hardened properties of concrete, particularly particle size distribution, workability, strength development, and durability. To achieve the objectives of the study, concrete mixes were prepared using a nominal mix ratio of 1:2:4 and a constant water–cement ratio of 0.50. Cow bone ash was used to partially replace cement at replacement levels of 0%, 5%, 10%, 15%, 20%, and 25% by weight. Laboratory tests were conducted in accordance with relevant British and ASTM standards. These tests included sieve analysis to determine particle size distribution, slump test to assess workability, compressive and flexural strength tests at curing ages of 7, 14, and 28 days, and water absorption tests to evaluate durability characteristics. The results showed that concrete containing 5–10% cow bone ash exhibited improved performance compared to the control mix. At these replacement levels, improved particle packing and additional calcium silicate hydrate (C–S–H) formation led to enhanced strength and reduced water absorption. However, workability decreased with increasing CBA content due to higher water demand, and replacement levels above 15% resulted in reduced strength and increased water absorption caused by higher porosity and unreacted ash particles. In conclusion, cow bone ash can be effectively used as a supplementary cementitious material at replacement levels of up to 10–15%, offering an environmentally friendly and cost-effective alternative to conventional cement in concrete production.

Heavy metal pollution has become a critical environmental challenge, particularly due to the persistence and toxicity of metals such as copper in aquatic ecosystems. Conventional treatment methods for metal removal, including chemical precipitation, ion exchange, and membrane filtration, are often costly, inefficient at low metal concentrations, and produce secondary waste. In response, biosorption has emerged as an eco-friendly and sustainable alternative. This study investigates the potential of corn cobs, an abundant agricultural by-product, as a low-cost biosorbent for the removal of Cu2+ ions from aqueous solutions. The biosorbent was prepared through collection, washing, drying, crushing, and sieving of corn cobs to obtain uniform particle sizes. A Box-Behnken Design (BBD) under the Response Surface Methodology (RSM) framework was employed to optimize process parameters such as adsorbent dosage, contact time, and metal concentration. Experimental data were fitted to a quadratic model, and statistical analysis through ANOVA revealed that the model was highly significant (F-value = 116.31 , P < 0 .0001) with strong correlation coefficients (R2 = 0.9934, Adjusted R2 = 0.9848, Predicted R2 = 0.9135). Optimization results indicated maximum copper ion removal of 94.73% at the optimal conditions of 5.5g/L adsorbent dosage, 67.5 minutes contact time, and 6 mg/L initial metal concentration. The model validation confirmed close agreement between predicted and experimental results, demonstrating the reliability of the developed model. Thermogravimetric and differential thermal analyses (TGA/DTA) suggested that the corn cob biosorbent possessed good thermal stability, which supports its suitability for adsorption applications. The study concludes that corn cobs are an effective, sustainable, and economical biosorbent for copper ion removal from wastewater. It further recommends their potential application in small- to medium-scale industrial effluent treatment systems. Future research should focus on kinetic and isotherm modeling, column adsorption studies, and biosorbent modification to enhance adsorption efficiency and extend applicability to other heavy metals.

This research investigates the feasibility and performance of polymer flooding as an enhanced oil recovery (EOR) method for Nigerian sandstone reservoirs. With the growing need to improve oil recovery from mature fields and reduce dependency on primary and secondary recovery techniques, polymer flooding has emerged as a promising tertiary recovery strategy. The study focuses on evaluating the technical and operational effectiveness of injecting hydrolyzed polyacrylamide (HPAM) polymer solution under representative Nigerian reservoir conditions using the CMG-STARS simulation software. A detailed reservoir model was developed, incorporating a six-layer sandstone formation characterized by an average porosity of 20%, initial pressure of 2299.2 psi, and oil viscosity of 5 cP. Two simulation cases were analyzed: a base case (without EOR) and a polymer flooding case with a 2000 ppm polymer solution injected over a 30-year production period (2025–2055). The performance of both scenarios was evaluated based on field oil production rate, bottom-hole pressure, water cut, and cumulative oil recovery. The results revealed that polymer flooding significantly improved reservoir performance compared to the base case. While the base case exhibited a steady decline in pressure and oil rate leading to early depletion around 2047, the polymer injection maintained an average pressure of about 2100 psi throughout the simulation. The polymer case also achieved a cumulative oil
recovery of 23.6 million stock tank barrels (MMSTB), representing an incremental gain of 5.8 MMSTB (32.6%) over the base case. Furthermore, water cut was reduced from 89% to 68%, indicating better mobility control and sweep efficiency. These findings confirm that polymer flooding is a technically viable and cost-effective EOR method for Nigerian sandstone reservoirs, capable of improving oil displacement efficiency and extending field life. The study recommends that field pilot projects be implemented to validate simulation outcomes and optimize polymer formulation for local reservoir conditions. Overall, this research demonstrates that polymer flooding can play a vital role in maximizing Nigeria’s oil recovery potential, supporting energy sustainability, and promoting efficient reservoir management.

This study assessed the water quality of the fish pond located at the Faculty of Agriculture, University of Benin, with the aim of determining its Water Quality Index (WQI) and proposing environmentally sustainable alternative uses in the event of water exchange or discharge. The study was carried out in response to the growing need for scientific evaluation of aquaculture effluents, which, if improperly managed, may cause ecological degradation through nutrient enrichment, heavy metal buildup, and microbial contamination. The research therefore sought to evaluate the physicochemical and microbial characteristics of the pond water, compute its WQI using the Arithmetic Weightage Index Model, and recommend safe reuse or disposal options. Water samples were collected from two ponds (Sample A and Sample B) representing five-day and thirteen-day retention periods respectively. Laboratory analyses were performed in the Civil Engineering Hydraulics/Water Laboratory following APHA (2017) standard methods to determine parameters such as pH, turbidity, total dissolved solids (TDS), total suspended solids (TSS), etc. The obtained data were analyzed using the Arithmetic Weightage Index Model, where individual parameter values were compared against WHO (2017) and FAO (2011) standards to derive the overall WQI and corresponding water quality grades The results showed that Sample A, with a WQI of 20.41, was classified as Excellent, indicating that the pond water met acceptable limits. Sample B, with a WQI of 51.69, fell under the Poor category, signifying moderate pollution resulting from prolonged water retention, organic enrichment, and higher microbial counts. Consequently, while Sample A water could be reused or safely discharged without treatment, Sample B water required simple treatment such as aeration or sedimentation prior to reuse or discharge. The study concluded that proper monitoring of water quality and periodic application of the WQI approach are vital for sustainable aquaculture management. It recommended regular effluent testing, adoption of low cost pre-treatment systems, and reuse of treated pond water for agricultural irrigation or secondary aquaculture to reduce environmental pollution and promote resource conservation.

Ikpoba River is the major recipient for municipal waste and industrial effluent in Benin City,samples of water were collected at five different locations in the river for some selected heavy metal analysis in order to determine the extent of pollution. Samples were collected in August to December 2021. Chemical analyses of samples river water and Dam was collected at predetermined sampling points were undertaken, the observations obtained were subjected to ANOVAand correlation analysis. Results obtained showed that each point source has its relative contribution to the overall degradation of the river water quality. The heavy metals were determined with atomic absorption spectrophotometry (AAS). From river water and dam the heavy metal concentrationwere found to be in the increasing order, fe>zn>cu> pb>Cd for all the five samples point collection as show in the result analysis. It also shows that the lead was not present in one of the point and Cadmium were not also detection in all of five sample. The analyses carried out also show the level of phosphate, nitrate, magnesium, pH, BOD,DO, electrical conductivity and turbidity in all the five stations and the turbidity was also notice to be relatively high. Most of the heavy metal determine were below the maximum permissible limit set by FEPA and WHO