| 1 |
Author(s):
Odenigbo C., Prof. Ademiluyi J.O., Onosakponome R. O. (Ph.D).
Page No : 1-14
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Modelling Electricity Generation from Biogas
Abstract
This study focused on the energy generation from the anaerobic treatment of the sewage sludge. The biogas yield obtained were used to power a micro gas turbine in order to determine electrical energy output from the system, a process that have now been commercialized for economic benefits. Equation 3.24 was derived and its consequent solution, equation 3.27 was used for that purpose. Figure 4.6 shows the energy output for experimental reactor 1. The result obtained shows a close fit between the turbine output and the model output. Precisely, a CORR value of 0.96 was obtained with a small error of estimate of 2.34 and 8.00 respectively for MAPE and RMSE. Similarly, figure 4.7 shows energy output for experimental reactor 2. In this, the coefficient of correlation was found to be 0.94 with MAPE and RMSE being 2.15 and 3.55 respectively. Figure 4.8 and 4.9 shows the energy output for model reactors 1 and 2 respectively. The CORR, MAPE and RMSE were 0.95, 3.78 and 5.51 respectively for model reactor 1 while a similar value of 0.97, 1.73 and 5.02 were recorded for model reactor 2 respectively. In all, a very good correlation values were obtained to show that energy generation from treatment plant can be modelled given the biogas yield data. It should be noted that turbine plant operational mechanism may vary slightly depending on their capacities; consequently, an updated recalibration of the model would be necessary.
| 2 |
Author(s):
Oriolowo Kolawole Taofik, Oladejo Kolawole Adesola, Abu R., Adekunle Nurudeen Olatunde.
Page No : 15-27
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Development and Performance Evaluation of Small-Scale Palm Kernel Cracker
Abstract
Cracking of palm kernel is a common process in order to separate the palm seeds from the kernel. Though, the palm kernel has been cracking with the aid of stone, ever since, due to the technological advancement there has been various palm kernel cracker machine on which there has been an improvement on them from time to time. It was observed that most people engage in palm kernels cracking were rural dweller, even some that are living in urban city are facing with incessant supply of electricity, therefore there should be a means of addressing the aforementioned shortcomings. This work aimed at producing a portable palm kernel cracker machine powered by gasoline motor with easy mobility that will reduce cracking time and human energy from local materials. The machine has main components: hopper, cracking chamber, bearing cover, frame assembly and puller. The Palm kernel nuts are mechanically cracked with the aid of centrifugal rotating three arms hammer that beats the Palm kernel from the seed. The machine optimum performance gave a throughput capacity of 401.4 kg/hr, cracking efficiency of 95.6%, split losses of 9.3% and uncracked losses of 6.2%. With the aforementioned capacity of the machine, the associated problems and difficulties in the traditional method will be culminated. With these attributes, this machine is suitable for both small and medium scale processors.
| 3 |
Author(s):
M. N. Nwigbo.
Page No : 28-35
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Effects of Heat Treatment on the Strength and Hardness of Hot Rolled 2SR, 3SR and 8SR Aluminium Alloys
Abstract
This paper examines the effects of selected heat treatment processes on the strength and hardness of hot rolled aluminium alloys, namely 2SR, 3SR and 8SR. Three heat treatment processes – annealing, solid solution heat treatment and precipitation heat treatment, are carried out on the alloy samples and their effects on the samples are evaluated by subjecting the samples to tensile and hardness tests before and after heat treatment. The results indicate an increase in hardness with 2SR aluminium alloy after annealing and solution heat treatment processes, and a drop in this property upon subjecting the sample to precipitation annealing, implying that the 2SR aluminium alloy can be better hardened by both annealing and solution heat treatment processes. On the other hand, precipitation heat treatment softens the alloy. This trend is equally applicable to 8SR sample but with a total deviation from this trend with 3SR sample, in which hardness decreases with each heat treat process. The results also suggest aluminium alloys 2SR and 8SR can be better hardened by both annealing and solution heat treatment processes and softened by precipitation hardening. However, 3SR alloy cannot be hardened by any of the heat treatment processes.
| 4 |
Author(s):
Orua Antia, Ubong Assian, William Olosunde.
Page No : 36-47
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Development of an Empirical Model Relating Palm Nut Moisture Content, Shell Thickness and Soaking Time
Abstract
This paper attempts to offer the use of shell thickness and soaking time to obtain any desired moisture content of dried palm nuts soaked in water at room temperature. In this study nuts were categorized into three size ranges based on its minor axis dimension (d_1) and then dried to dry bone mass. The nuts for each experimental run were subjected to soaking per size range per vessel containing water. The experimental data were obtained at 3 –hourly intervals for parameters (nut axial dimension, thickness and mass) considered. Moisture content was computed and statistical analysis carried out. Result revealed that dried palm nut shell thickness and soaking time, apart from any other possible parameter(s) influence water absorption by the nuts vis-à-vis moisture content. The empirical equation developed was tested, validated and found to be useful in estimating soaking time for dried palm nut to attain any desired moisture content.
| 5 |
Author(s):
Orua Antia, Ubong Assian, William Olosunde.
Page No : 48-55
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Effect of Moisture Content on Palm Nut Shell Fragmentation for Effective Separation of Kernel
Abstract
The search to accomplish effective separation of kernels from cracked nut mixture necessitated this work. In this study, nuts of bone-dry mass were soaked in water at room temperature and then subjected to cracking at 3-hourly intervals. The shell fragments and kernels obtained were further subjected to impact in order to examine the cycles of impact that would produce low % split kernels and high % shell fragments that could be sieved out while retaining on the sieve a high % kernels. Result revealed that at moisture content of 8.31% wb, impact energy of 0.4 J, impact speed of 25.32 m/s and 2 – 3 impact cycles, an effective separation of kernel was possible through production of shell fragments sizes that was sieved out to leave behind high % of kernels.
