Modeling of 1.0 MW-h Combustible Waste Fuel Steam Thermal Station: A Panacea for Rural/Off-Grid Areas’ Electrification

The problem of energy crisis can be best handled by making a more prudent use of some of those materials viewed as wastes. This study seeks to show how conversion of this waste to fuels can help tackle some of these energy dependent problems. A model of 1.0 MW-h steam thermal station was developed that could utilize wood and palm residues, produced by saw and palm oil mills, as fuels. Ondo and Edo States in southern part of Nigeria were considered as catchalls and data obtained from Mills in these States were used for this evaluation. Estimates were made of the capacity of these residues to evaluate the viability of the study. The Model requires 3.404 tons of waste wood or 2.70 tons of palm kernel residues per hour to meet the turbine steam consumption of 3.37 kg/s. The results revealed that the project would thrive well in the two states when wood residue is considered but could only be effectively in Edo State when firing on palm residue. The viability of the research as a panacea to ameliorate problems of power outages were validated using two software, Boiler efficiency and steam turbine consumption. Keywords: Wastes, Steam,  Electricity, National Grid, Development and Wealt

Development of A Dual-Fired Dryer for Augmentation of Fish Preservation

Food serves as one of the basic requirements for the well-being of every living being, but improper handling during post-harvesting stage to cater for the rainy day in the midst of insufficient energy source, is one of the factors responsible for food insecurity, especially in the developing countries. This study focused on the construction and evaluation of an adaptable dual-fired fish dryer. The dryer, designed to reduce moisture content of fish from 80% to 8% for proper product shelf life, has a rated drying capacity of 12 kg of fish per period of 4 hours per batch, while working on either electricity or natural gas as source of heat energy. Locally available materials were used in the construction of the device. The rig developed cost one hundred and forty-eight thousand eight hundred and twenty Naira (N148, 820.00). It was evaluated using salmon fish. The dryer is more efficient when electrically fired than when gas-fired and has the maximum drying and thermal efficiencies of 84.67 % and 92.93 % when operated at 85oC while the corresponding values when operated on gas are 36% and 62.65% respectively. Keywords: Food insecurity, Fish, dryer, Performance evaluation, Preservation, Incom

Development of a Refrigerant Recovery and Recycling Machine

Indiscriminate discharge of refrigerants into the atmosphere during servicing or overhauling of refrigerating systems by Heating, Ventilation and Air-conditioning (HVAC) Practitioners is one of the major contributing factors to ozone depletion and climate change. The objectives of this study are to: design, fabricate and evaluate the performance of refrigerants recovery and recycling machine. The machine with 19.44 kg/hr rated capacity produced at cost of N106, 503.00 (about USD 500) with locally sourced materials comprises: compressor, drier, capillary tube, solenoid valves, two (2) pressure gauges and heat exchanger as functional parts. In order to evaluate the performance of  this machine, R-12 and R-22 refrigerants were considered for its analysis and results showed that for every 1 kg refrigerant recovered and recycled it has average recovery and recycling efficiencies of 88.5 % and 85.68 % whilst recycling used refrigerant to 99.9 % of its original purity. Keywords: Refrigerants, Ozone Depletion, Global Warming, Recovery, Recycling, Performance evaluatio

Evaluation of andrological indices and testicular histology following administration of varied doses of nicotine

This study is aimed at determining the effect of Nicotine on male fertility by evaluating some andrological parameters of male Wistar rat such as sperm parameters (spermatozoa count and motility), serum concentration of testosterone and testicular weight. Histopathology of the testis was also carried out on the effect of nicotine on testicular microstructure. 20 adult male rats were randomly divided into four groups, the test groups were administered with 0.2mg/100g, 0.4/100g and 0.6/100g body weight daily for 30 days while the control were administered with 2mls 0.9% physiological saline. Nicotine caused a significant reduction (P < 0.05) and (P< 0.01) in the mean values of sperm count, serum testosterone concentration and testicular weight in the test when compared with the control. Also, in the test group, the deleterious effect of nicotine on the sperm parameters and testosterone concentration was corroborated by histopathology which revealed a marked degeneration of germ cell layers in the seminiferous tubule and disruption of interstitial cells of the testis thereby interfering with spermatogenesis and testosterone secretion while there was no visible change in the control group. It was concluded that nicotine exerted toxic effect on the germ cell layers in seminiferous tubule with concomitant reduction in reproductive potentials of the male rat whilst showing no significant change in sperm motility. Nicotine and nicotine based products should therefore be taken with caution in cases of infertility. Key words: germ cells, testes, testosterone, fertility, spermatogenesis

Micromechanical Properties of Injection-Molded Starch–Wood Particle Composites

The micromechanical properties of injection molded starch–wood particle composites were investigated as a function of particle content and humidity conditions. The composite materials were characterized by scanning electron microscopy and X-ray diffraction methods. The microhardness of the composites was shown to increase notably with the concentration of the wood particles. In addition,creep behavior under the indenter and temperature dependence were evaluated in terms of the independent contribution of the starch matrix and the wood microparticles to the hardness value. The influence of drying time on the density and weight uptake of the injection-molded composites was highlighted. The results revealed the role of the mechanism of water evaporation, showing that the dependence of water uptake and temperature was greater for the starch–wood composites than for the pure starch sample. Experiments performed during the drying process at 70°C indicated that the wood in the starch composites did not prevent water loss from the samples.Peer reviewe

The EFFECT OF INNOCULUM ON BIOGAS PRODUCTION FROM CASSAVA PEELS

This paper investigated the innoculum effect on cassava peels for biogas production. Cassava peels was mixed with cattle dung and poultry droppings as innoculum by mass into six different combinations. Each mixture was mixed with 12 litres of water before charging to different digesters made of plastics and equipped with mercury-in-glass thermometers and pressure gauges on their top surfaces. The mixtures include 6 kg of cassava peels; 3 kg each cassava peels and cattle dung; 3 kg cassava peels with 3 kg poultry droppings; 2 kg each of cassava peels, cattle dung and poultry droppings; 2 kg cassava peels with 3 kg cattle dung and a kilogram of poultry droppings; and 2 kg cassava peels with a kilogram of cattle dung and 2 kg poultry droppings. The pH of the contents of the digesters was also monitored. The digesters were monitored for 100 days for biogas production in a laboratory at the Federal Polytechnic, Ado-Ekiti, Nigeria. Biogas from each digester was daily tested for combustion as their temperatures and pressures were monitored at 10 am and 4 pm. The results indicated that pH 6.2 for the cassava peels digester. This increased to 7.0 as the quantity of cassava peels reduced in other digesters. The lowest morning ambient and digesters temperatures were respectively 22 oC and 21 oC while the maximum temperatures were 39 oC and 40 oC for the evenings. There were earlier and higher biogas productions with the addition of the innoculum in the digesters. The combustion time of the biogas reduced with increase in the masses of the innoculum

The unusual finding of peripheral lymphadenopathy among confirmed Lassa fever patients in Nigeria

Lassa fever is a viral haemorrhagic fever belonging to the arenaviridae family that is well known to be endemic to West Africa. The clinical presentation of the disease ranges from asymptomatic to fulminant illness. Lymphadenopathy a clinical manifestation of inflammation, infection, or malignancy has not been widely reported in Lassa fever disease. We report two cases of Lassa fever disease presenting with lymphadenopathy