ARID ZONE JOURNAL OF ENGINEERING, TECHNOLOGY AND ENVIRONMENT

The Study and Analysis of Cell Phone Charging Modules in Nigeria

G. I. Efenedo — 2024-09-02

Cellular phones require frequent charging with the aid of modules known as chargers. The performance of chargers in Oleh, a community in the Niger Delta area of Nigeria as a case study were investigated with a view to proffering solutions arising from the conventional act of disposing failed chargers without attempted remedies by users. Twenty (20) chargers were sampled and examined to determine the electronic components most likely prone to failure in the modules and possible reactivation. Also, experiments were performed to compare charging rates to initial specifications by manufacturers for the sampled chargers. The results show that the components most likely prone to failure from the sampled chargers in order of frequency of failure were circuit breakers, capacitors, switching rectifier and switching power transistors. Furthermore, one of the reactivated chargers model, Infinix of initial specification mostly available in Nigeria with open-circuit voltage of 5.00V and short-circuit current of 1500mA, recorded 4.50V, 800mA and was able to charge Samsung A12 phone to full capacity (100%) in twenty(20) minutes at a charging rate of 0.01V.min or -4.67A/min respectively. Similarly, reactivated Oraimo charger recorded 4.70.00V, 2500mA as against 5.00V, 900mA specifications when charging the Tecno Pop2 phone. The results show that the reactivated modules charging performances were comparatively enhanced at current delivery to loads as shown by the two cell phones. Therefore, it is recommended that Engineers and Technicians skills be chandelled towards local design and reactivation of failed charging modules in Nigeria.

Development of Axle Load Spectra for Integration in Traffic Characteriaztion for Nigerian Empirical Mechanistic Pavement Analysis and Design Systems

D. O. Awosanya — 2024-09-02

Design traffic is employed in this research to estimate the expected load repetitions for a given axle load spectrum during the pavement life. In changing traffic characterization in mechanistic-empirical (M-E) design procedure, the process does away with the equivalent single axle load (ESAL) concept and traffic analysis implementation was done by directly using axle load. Comparison of predicted Number of Axle load range repetitions determined by equivalent axle load factor (EALF) and general axle load equivalency factors (GAF), is the main objective. In this study, axle load spectrum by Weigh-In-Motion (WIM) data and parametric standard axle loads which cause equal damage were collected and utilized. Determination of the axle load distribution factor (ALDF) from the WIM data. It is a critical input in the method based on different axle load groups for the estimation of the predicted number of axle load repetitions during the pavement design period. The results that the marked difference on the estimated predicted axle load predictions with the determination of EALF and GAF 63.95% of GAF value for SAST. Similarly, 10.14% for SADT; 30.24% for TADT and 21.43% for TRDT. This indicates the inherited error in the empiricism content in the empirical approach of handling traffic, for the determination of EALF. The estimated traffic prediction value increases as the captured axle load magnitude increased, as a resultant of the type of commodities and goods carried on the roadway pavement.

Development of a Palm Nut Cracker with Spinning Disc Shell Separator.

B. O. Lukman — 2024-09-02

This paper presents the design and evaluation of a palm nut cracker with a spinning disc separator. The machine has five units namely: the hopper, the cracking chamber, the separating unit made of a vibrating screen and a spinning disc, the collectors, and the drive unit. The machine was designed and fabricated using locally sourced materials, and it was tested and evaluated at two operating speeds (480 and 660rpm) with palm nuts at three moisture contents of 5, 10, and 12%, respectively. The kernel-shell mixture was separated using the spinning disc made of three different materials; mild steel, plywood, and jute fiber. At a constant feed rate of 50 nuts per second, the cracking unit achieved a maximum cracking efficiency of 94.52%, while the throughput capacity was 8.05 kg/hr at 660 rpm for nuts with a moisture content of 10%. The spinning disc constructed of mild steel had the highest separation efficiency of 69.2% and kernel purity of 90.69% for cracked mixture with 12% moisture content at 60 rpm.

Environmental Trends Due to Arc Welding Activities: Sensitivity of some Typical Workplaces

A. S. Shote — 2024-09-02

The associated hazards with welding process are recently looked into because of the emission threat or lack or improper use of safety devices in work places relating to welding that could potentially lead to long- or short-term effect on worker and other staying nearby. This article provides data for various air quality parameters such as Total Volatile Organic Compounds (TVOC), Air Quality Index (AQI), Carbon Monoxide (CO), Carbon Dioxide (CO2), and Formaldehyde (HCHO) measured at different locations, North (N), West (W), East (E), and South (S) within Lagos Metropolis. The results of CO and HCHO levels are apparently higher than recommended limits in some locations (East and South) which suggest potential harm for workers as CO is mostly dangerous to health. However, other data suggests that air quality is generally good, as all AQI values are significantly below the break point of 50ppm. Further analysis revealed that at 95% confidence, there is no significant difference in the CO emissions patterns from different workshops as well as from different locations (North, West, East, and South) as Pvalue> 0.05. However, there is difference in CO2 as a result of change in locations as Pvalue (0.014) < 0.05. About 57.6% of the variability in CO2 emissions from various locations can be accounted for due to the variation resulting from change in location. The data thus provides useful information that could enable enforcement of personal protective equipment to ameliorate the situation.

Electrical Resistivity Survey for Groundwater Investigation in Parts of Osun State, Southwestern Nigeria.

S. A. Adebiyi — 2024-09-02

This study used a non-invasive, cost-effective geophysical method for locating suitable sites for groundwater development. Thirty-two Vertical Electrical Sounding (VES) were probed in the investigated area using Schlumberger array. The data acquired were interpreted using the partial curve matching technique and computer-aided iteration through WINRESIST. The aquifer properties such as transverse resistance, longitudinal conductance, hydraulic conductivity and transmissivity were computed from the primary geoelectric parameters. The results of the study revealed that the investigated area is marked by heterogeneous lithology with three to five geoelectric layers. The aquifer resistivities ranged from 18 to 318 Ωm while the aquifer thicknesses ranged from 1.7 to 46.2 m. The computed transverse resistance revealed the groundwater development in the investigated area as low/moderate. Also, the transmissivity values computed from the primary aquifer parameters revealed that 72% of the investigated area has low aquifer transmissivity, while 28% have moderate aquifer transmissivity. This implies that the investigated area has low/moderate water-bearing potentiality. The quantitative analysis of the aquifer protective rating revealed that 78.1% of the investigated area has a good natural ﬁlter. Based on the aquifer potential rating and the protective capacity, VESes 10-12, 16, 19-20, 23-25 were recommended for drilling sites. The result of this study provides some important conclusions for future groundwater exploration and management in the investigated area.

Integrating Bowtie Analysis into Band Saw Maintenance

T. K. Tsapi — 2024-09-02

Sawing machines used to cut raw materials to desired dimensions in industrial manufacturing operations are of great importance. Occupational injuries have occurred in the past as a result of failures in the risk management of these machines. In this paper, Bowtie analysis-based risk identification is developed based on the diagnosis of band saw cutting machine components. The results of the Bowtie risk assessment for hazards associated with the impeller, pump housing, saw blade, clamp, and seal pump were developed to structure the decision-making process with better information visualization. Hazards in the Bowtie were used to describe the root causes of failure (threats) that were identified, such as inadequate maintenance planning, foreign objects entering the pump, and inadequate maintenance. Based on the Bowtie diagrams, which capture the sufficient complexity of the real system behavior, the cutting tool was maintained following a corrective action plan that was developed. The assessment of the band saw performance rate after maintenance was 93%. This demonstrates that decision-makers can manage risk and reinforce a work culture that prioritizes actions to improve maintenance and safety outcomes using the Bowtie analysis method.

Compressive Strength and Splitting Tensile Strength of Concrete Cube Using Magnetized Water

M. M. Adiama — 2024-09-02

Report on cases of collapse of residential buildings and other structures are common in Nigeria which is normally due to structural failure, failure of the materials that were used for the construction and poor design. Buildings Collapse normally results to loss of lives and properties. The study was conducted to determine the effect of Magnetized Water (MW) on the Compressive Strength (CS) and Splitting Tensile Strength (STS) of Concrete Cubes (CC). MW is the water that has passed through magnetic field which could enhance proper hydration of concrete and improve the strength of CC. The CC was produced using sand (4.75 mm diameter), ordinary Portland cement, crushed granite (12 mm diameter) and MW. The mixing ratio of cement, sand and granite for the CC was 1:2:4 and water-cement ratio was 0.5. The treatments were T1 (concrete produced with Non-Magnetized Water -NMW and cured in MW treated for 1 minute), T2 (CC with MW treated for 1 minute and cured in NMW), T3 (CC with MW treated for 1 minute and cured in MW treated for 1 minute), T4 (CC with MW treated for 2 minutes and cured in NMW), T5 (CC with MW treated for 2 minutes and cured in MW treated for 2 minutes) and control T0 (CC produced with NMW and cured in NMW). CS and STS were determined after cured for 7, 14 and 28 days. The mean CSs after cured for 28 days T1, T2, T3, T4, T5 and T0 were 18.13, 22.00, 23.40, 19.07, 17.87 and 18.66 N/mm², respectively. The mean STSs after cured for 28 days T₁, T₂, T₃, T₄, T₅ and T₀ were 1.33, 1.38, 1.59, 1.83, 1.21 and 1.32 N/mm², respectively. MW increased the CS and STS by 25.40% and 37.57% of the concrete cubes, respectively. This shows that magnetized water is economical, simple and environmentally-friendly technology for the production of concrete cubes.

Optimization of Groundnut Oil Extraction using Chemical Method

H. H. Mari — 2024-09-02

The chemical extraction technique is associated with suboptimal oil yield and quality, necessitating the development of optimized extraction technique. In this study, groundnut oil was extracted chemically with n-hexane using the Response Surface Methodology (RSM) and the extraction process was optimized considering the hexane concentration (30, 40 and 50), extraction duration (3, 5, 7 hrs) and the amount of groundnut (15, 20, and 25 g) as factors and the oil yield was evaluated. The Fourier Transform Infrared (FTIR) technique was used to check at the functional groups on the extracted oil. In the experimental results, the average optimum values of extraction time, solvent amount, groundnut amount, and oil yield were 5.05 hr, 40.5 mL, 20.25 g, and 48.18%, respectively. The profiled extracted oil by FTIR showed peaks at 3452 cm-1 2969 cm-1 2712 cm-1 1763 cm-1 1474 cm-1 which indicates the existence of -CH and OH, CH, C-H, aldehydes, ketones, carboxylic acids, and methylene groups functional groups which are useful for determining the oil's quality. Furthermore, findings from this study showed that RSM-optimized process parameters result in significantly greater oil yields than conventional approaches.