LAUTECH Journal of Engineering and Technology (LAUJET)
Not a member yet
571 research outputs found
Sort by
COMBUSTION AND MECHANICAL PROPERTIES OF BAMBOO (BAMBUSA VULGARIS) AND THREE INDIGENOUS WOOD CHARCOALS
Get PDFThis study investigated the combustion and mechanical properties of bamboo (Bambusa vulgaris) charcoal and three indigenous wood charcoal (Teak ,Tectona grandis; Afara, Terminalia superba and Omo, Cordia millenii). Results revealed that there were no significant differences in the properties charcoal produced from bamvboo and the tree indigenous wood. Bamboo and Afara were the most efficient out of the charcoal samples considered in the study. Although the fuel value index of Bamboo was quite lower than that of Afara and other samples considered in the study, but its calorific value was higher than Afara. However, it has greater potentials to replace woody biomass as fuel. Bamboo can replace other wood species in the production of charcoal because of its faster growth rate
THE POTENTIAL OF NEEM SEED OIL (AZADIRACHTA INDICA) AS NATURAL HOUSEHOLD INSECTICIDE
Get PDFUse of synthetic insecticides has resulted into health hazards, ecological imbalance, resistance by pests and environmental pollution. Neem seed oil is reported to be a natural pesticide that has excellent insecticidal properties whose usage will reduce the risks associated with the use of synthetic insecticides.
In this study, attempts were made to formulate neem seed oil-additive emulsions to be used as insecticide on household pests. Solvent extraction method was used for extracting oil from neem seed while acetone and calcium oxide were used as additives (inert ingredients) to formulate emulsifiable medium which were tested on four common household pests (cockroaches, black ants, soldier ants and millipedes).
It was observed that the additive samples to which 5 ml of neem seed oil were added were the most effective and active of all the tested mixture samples. The insects were either killed or their movement retarded within the shortest time compared to other samples with lesser amount of neem seed oil
The results of the study showed that extracted oil from neem seed in emulsions with additives can be used as natural household insecticides. Also, acetone and calcium oxide used as additives (inert ingredient) readily improve the insecticidal properties of the neem seed oil with acetone being the most effective
REVIEW ON CASSAVA MASH SIF TING METHODS AND MECHANISMS
Get PDFCassava is presently the most important food crop in Nigeria from the point of view of both the area cultivated and the tonnage produced.Cassava has transformed greatly into high yielding cash crop, a foreign exchange earner as well as a crop for world food security and industrialization. As a result of this, there has been an unprecedented rise in the demand for cassava and its numerous products worldwide for both domestic and industrial applications. However, cassava processors are currently finding it extremely difficult to respond positively to this increase in demand due to the prevalence of the traditional processing methods employed the sifting operation inclusive. This has made the appraisal of the current sifting technologies pertinent in order to address the areas that need technical improvement and further research efforts towards the evolution of cost effective sifting technologies with improved efficiencies which would enhance the capacity to exploit the cassava market potential. Therefore, this paper reviews the efforts made, and currently being made towards an efficient and cost effective mechanization of cassava mash sifting operation so as to overcome the challenges being faced using traditional method of sieving cassava mash
PILOT STUDY ON LOW COST DOMESTIC SLOW SAND FILTER FOR GROUNDWATER QUALITY IMPROVEMENT
Get PDFMost waterborne diseases can be prevented using simple, low cost water filtration techniques. The aim of this study is to design a low cost domestic slow sand filter, which can be operated and maintained effectiveness at household level by a member of the family, and determine its effectiveness in removing selected contaminants from the raw groundwater. Fine sand, activated charcoal, coarse sand, and gravel were used as media column for the developed slow sand filtration media. Common selected physico-chemical and microbial water parameters were examined before and after filtration with the slow sand filtration system. The filter was able to remove turbidity of the raw groundwater in the range of 86 - 92% without hampering the pH value or the temperature below the acceptable standards set by the Nigerian standards for drinking water quality. The filter media was able to reduce an average of 44 - 82%, 29 - 53% and 60 – 66% of total hardness, calcium hardness and chloride content, respectively from the chemical composition of the groundwater samples. The media also showed high effectiveness in reducing biological impurities from the groundwater. It was able to remove effectively the concentration of E-Coli and coliform counts. The average percent removal of E-coli and coliforms was found to be 100%. These were achieved with the aid of the bio-film layer that developed on the topmost part (fine sand layer) of the filter which was able to predate on the microbes in the groundwater samples. Slow sand filters are a sustainable means of water treatment when applied to appropriate source waters and when designed and operated properly. 
PERFORMANCE IMPROVEMENT OF POWER SYSTEM NETWORKS USING FLEXIBLE ALTERNATING CURRENT TRANSMISSION SYSTEMS DEVICES: THE NIGERIAN 330 KV ELECTRICITY GRID AS A CASE STUDY
Get PDFA wide electricity supply-demand gap especially in developing economy such as Nigeria has created series of challenges such as frequent power outages, poor voltage profile and high power losses among others yet to be addressed. This work examines the effect of Static Var Compensator (SVC), a Flexible Alternating Current Transmission Systems (FACTS) device for performance improvement of power system networks with the Nigerian 330 kV, 28-bus electricity grid considered as a test network. The steady state performance of the system was modeled using Newton-Raphson load flow equations and was simulated without and with compensation on MATLAB/PSAT toolbox (version 2.1.9 ‘R2012a’). The obtained results showed that the system voltage profile improved to acceptable limit defined as with compensation compared to when voltage magnitudes of buses 9, 13, 14, 15, 16, 19, 22 and 26 of the test network fell outside of the acceptable limit without compensation. Also, the system total active power loss reduced from 15.727 MW without SVC to 14.709 MW with SVC, giving a 6.47% reduction in total active power loss. These results showed that the inclusion of SVC on the Nigerian electricity grid will improve both voltage profile and power transfer capability of the system.  
PERFORMANCE OF A NOVEL HELIUM-STIRRED SOLID OXIDE FUEL CELL WITH MOLTEN METAL ANODE FOR ELECTRICITY GENERATION AND OXYGEN DISSOLUTION IN MOLTEN METAL
Get PDF A novel helium-stirred solid oxide fuel cell (SOFC) with a molten metal anode for electricity generation and oxygen dissolution in a molten metal was investigated. This SOFC configuration employs conventional cathode and electrolyte but incorporates a molten metal contained in an alumina crucible as anode and inert gas stirring of the molten metal. Tin was the metal used in this study because it is non-toxic and inexpensive, it also has a relatively low melting point and very low vapour pressure at high temperatures. The performance of a SOFC with molten tin anode at 850 oC was evaluated by the techniques of electrochemical impedance spectroscopy, cyclic voltammetry and chronoamperometry. A peak power density of ca. 100 W m-2 at a potential difference of ca. 0.45 V and current density of ca. 222 A m-2 was achieved. Impedance spectra showed that ohmic potential losses controlled the reactor performance, with about 59% of those arising from the inherent difficulty in achieving a low resistance contact at the silver wire (silver wool) current collector | cathode interface. The molten metal bath provided a relatively large reservoir of molten metal for oxygen absorption and transport compared to a thin film of molten metal while gas stirring of molten metal enhanced the transport of dissolved oxygen atoms from the yttria stabilized zirconia (YSZ) electrolyte | molten metal interface to the bulk molten metal and assisted in preventing oxide formation at the YSZ electrolyte | molten metal interface. 
LAND USE DYNAMICS ANALYSIS FOR SUSTAINABLE DEVELOPMENT PLANNING USING GEO-INFORMATICS TECHNIQUES: CASE STUDY OF OGBOMOSO TOWN, NIGERIA
Get PDFLand use and Land cover mapping is an important task to conserve natural resources and to recommend suitable management practices. Understanding land use dynamics will help countries in land management thus preserving their natural resources. Geo-Informatics has been increasingly used for mapping land use and land cover due to specific characteristics of remotely sensed data such as resolution, accessibility to remote areas and faster interpretation with higher degree of objectivity and reproducibility. This study thereby mapped land use dynamics of Ogbomosho North Local Government area using Geo-informatics techniques between year 1984 and 2016. ArcGIS software package was used for the supervised classification in the study. The total area covered by the assessed land is about 253 Km2. The classification result of 1984 imagery showed that water body occupied 1.2% of the study area; shrub, 34.4%; arable land, 57.8%; built-up, 6.4% and bare land, 0.2% of the study area resulting into decrease in year 2000 and year 2016. The maps generated showed increase in water buddies, built-up area, pave and rocky areas and in vegetal and in other agriculture land, but decrease in forest land depicting loss of agricultural land, modification and alterations in the land use/land cover changes over time
WASTE TO WEALTH - CONVERSION OF POULTRY LITTER FROM RAW FORM TO PELLETED ORGANIC FERTILIZER
Get PDFA review of the use of pelletized poultry litter for creation of wealth through use as organic fertilizer was done, using information from literature and data from field observation. Poultry wastes, which are a menace to the environment, are sources of wealth creation, especially for organic farming. There is an abundance of poultry wastes in Nigeria, as about 932.5 metric tonnes of poultry manure is produced annually from the well-established poultry houses which keep expanding at the rate of 8% per year. Also, global trend is shifting to organic fertilizer as the use of chemical fertilizer over the years has destroyed our soil. Organic fertilizer has much organic content, which can rejuvenate the already destroyed soil. Not only that, organic fertilizer is safe for human health. Pelletized poultry litter would compete successfully as a soil conditioner or soil amendment. It would also be priced competitively, as it provides a unique mixture of nutrients and conditioning properties. Consequently, there is more poultry farming profitability, efficient resources utilization and conservation of environment due to waste management
SUSTAINABLE MANAGEMENT OF COW DUNG FROM SLAUGHTER HOUSES
Get PDFLarge amount of cattle dung are generated daily from slaughter houses which are not only of environmental concern due to methane emission but also present a significant health risk if not adequately managed. In this study, cow dung obtained from slaughter house was anaerobically digested and its composition evaluated.8 kg of the collected cow dung was mixed with water using a mechanical stirrer set at a speed of 150 rpm to form slurry before pouring it into a laboratory scale digester affixed with stirrer, inlet and outlet ports and temperature detector. The set up was left for 3days for microbial activation to take place, before daily stirring. Average weekly temperature of the slurry inside the digester tank was observed. Biogas produced was collected in a rubber tube and trapped with activated charcoal dissolved in 500 ml of carbon disulphide (CS2) for 120 minutes in an open air. The liquid filtrate was then analysed using a Gas Chromatography. The optimum temperature was observed at 36.5 OC. The digestion temperature variation was between 0.5 to 2 OC. Methane bacteria worked best in the temperature ranges between 34 and 37 OC. After the liquefaction process, 30 cm3 of biogas was generated. Out of which, methane occupied 25.002 cm3 (83.34 %), carbon dioxide 4.467 cm3 (14.89 %), nitrogen 0.468cm3 (1.56 %) while carbon monoxide generated was 0.063 cm3 (0.21 %). The result clearly show that methane has the highest yield, the energy contained in methane can be used as domestic gas.Cow dung is an excellent substrate for biogas production in anaerobic digesters instead of indiscriminate disposal. Bio-digestion of cow dung is a viable and sustainable solution to the problem of waste pollution, disposal, control and management
SYNTHESIS, CHARACTERISATION AND ANTIMICROBIAL ACTIVITY OF MIXED-LIGAND NICKEL(II) AND COPPER(II) COMPLEXES OF SALICYLALDEHYDE WITH 2,2?-BIPYRIDINE, 1,10-PHENANTHROLINE AND ETHYLENEDIAMINE
Get PDFNickel(II) and copper(II) mixed-ligand complexes of Salicylaldehyde with 2,2?-bipyridine, 1,10-phenanthroline and ethylenediamine were synthesised and characterised by molar conductance, spectroscopic measurement, room temperature magnetic measurement and antimicrobial activity. The complexes showed different shades of colour and were non-electrolyte. The infrared spectra of the complexes confirmed the coordination through the lone pair of the carbonyl oxygen of the Salicylaldehyde. The electronic transitions were consistent with the adoption of five-coordinate geometry for the copper complexes and six-coordinate geometry for the nickel complexes. The microbial susceptibility testing showed that the copper complexes had stronger antifungal activity than the antibacterial activity. The antifungal activity was more pronounced at 12.5 – 100 mg/mL, while the antibacterial activity was generally restricted to 100 mg/mL. Notably, [Cu(Sal)2(bipy)] showed no antifungal activity while [Cu(Sal)2(en)] showed neither antifungal nor antibacterial activity. Among the nickel complexes only [Ni(Sal)2(phen)] had both antifungal (except Fusarium) and antibacterial activity. [Ni(Sal)2(en)] was neither antifungal nor antibacterial