Featured Papers

done_all Engineering

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    Review of Palm Kernel Oil Processing And Storage Techniques In South East Nigeria

  • person_outlineAuthor(s): Okeke CG, Oluka SI
  • subjectCategory: Engineering
  • access_time19 June, 2017
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    An assessment of palm kernel processing and storage in South-Eastern Nigeria was carried out by investigative survey approach. The survey basically ascertained the extent of mechanization applicable in the area to enable the palm kernel processors and agricultural policy makers, device the modalities for improving palm kernel processing in the area. According to the results obtained from the study, in Abia state, 85% of the respondents use mechanical method while 15% use manual method in cracking their kernels. In Imo state, 83% of the processors use mechanical method while 17% use manual method. In Enugu and Ebonyi state, 70% and 50% of the processors respectively use mechanical method. It is only in Anambra state that greater number of the processors (50%) use manual method while 45% use mechanical means. It is observable from the results that palm kernel oil extraction has not received much attention in mechanization. The ANOVA of the palm kernel oil extraction technique in South- East Nigeria showed significant difference in both the study area and oil extraction techniques at 5% level of probability. Results further revealed that in Abia State, 70% of the processors use complete fractional process in refining the palm kernel oil; 25% and 5% respectively use incomplete fractional process and zero refining process. In Anambra, 60% of the processors use complete fractional process and 40% use incomplete fractional process. Zero refining method is not applicable in Anambra state.  In Enugu sate, 53% use complete fractional process while 25% and 22% respectively use zero refining and incomplete fractional process in refining the palm kernel oil. Imo state, mostly use complete fractional process (85%) in refining palm kernel oil. About 10% use zero refining method while 5% of the processors use incomplete fractional process. Plastic containers and metal drums are dominantly used in most areas in south-east Nigeria for the storage of palm kernel oil.

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    Performance Characteristics of Agricultural Field Machineries In South- East Nigeria

  • person_outlineAuthor(s): Oduma O, Oluka SI
  • subjectCategory: Engineering
  • access_time19 June, 2017
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    The field performances of agricultural field machineries in South -East agricultural zone of Nigeria were assessed, to enable farmers and agriculturists select suitable farm machines/implements based on soil conditions/characteristics for their agricultural activities. The various implements studied include; disc plough, 2-gang tandem disc harrow, ridger, rotovator and 6-row combine seed planter. Three different makes and models of tractors namely: New Holland (model-NH5610SE and capacity-55.9kw), Massey Ferguson (model-MF430E and capacity-55.2kw) and Mahindra (model-NH7570E and capacity-55.9kw) with 3- point hitch systems and average age of 1.3 years were used to study the field performances of each of the implements, in five different states that made up the study area. The field performances studied include; implement’s working speed, operation time, depth of cut, effective and theoretical field capacities, field efficiency, fuel consumption rate, implement power requirements, and wheel slippage, under different soil conditions. Results obtained revealed that the disc plough had field efficiency range of 85.74% to 88.55%, effective and theoretical field capacities range of 0.846 to 1.164ha/hr and 0.961 to 1.319ha/hr respectively; and the highest field (ploughing) efficiency was obtained in loamy-sandy soil when the plough was operated with the Massey Ferguson tractor. Harrow recorded field efficiency range of 80.17 to 91.38%, effective and theoretical field capacities range of 0.931 to 1.458ha/hr and 1.151 to 1.667 ha/hr respectively; and the highest field (harrowing) efficiency was obtained on sandy-clay soil by New Holland tractor. Ridger recorded 83.65 to 88.82% field efficiency, 0.932 to 1.322ha/hr effective capacity and 1.073 to 1.504ha/hr theoretical field capacity; and sandy-clay gave the highest field (ridging) efficiency when operated with a New Holland tractor. The rotovator had field efficiency range of 81.10 to 89.81%, effective and theoretical field capacities range of 0.759 to 0.902ha/hr and 0.758 to1.039ha/hr respectively; and the highest pulverizing efficiency was achieved on the clay-loam soil with a Massey Ferguson tractor. The planter recorded 80.63 to 89.37 field efficiency,1.012 to1.481ha/hr effective field capacity and theoretical field capacity of 1.22 to 1.716ha/hr. Ploughing gave the highest average fuel consumption rate of 22.72L/ha (8.89L/hr), followed by harrowing with average consumption of 19.57L/ha (8.04L/hr), ridging recorded 19.42L/ha (7.97L/hr), rotovator had 16.79L/ha (7.19L/hr) and least was planter with average consumption rate of 15.10L/ha (6.26L/hr). More so, all implements recorded highest tyre slippage in sandy-clay soil, followed by loamy-sandy and the least slippage was recorded in the clay-loam soil. Results finally revealed that the highest draft force (10.8kN/m) was obtained by the plough, followed by the harrow and ridger with equal draft force values of 10.5kN/m respectively and least draft was recorded by the rotovator (5.1kN/m).

  • library_books

    SELECTED PHYSICAL AND AERODYNAMIC PROPERTIES OF AFRICAN BREADFRUIT (Treculia africana) SEEDS FROM SOUTH EASTERN NIGERIA.

  • person_outlineAuthor(s): Igwillo UC, Eze PC, Eze CN
  • subjectCategory: Engineering
  • access_time19 June, 2017
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    Physical and aerodynamic properties of African breadfruit (Treculia africana) seeds were studied at four moisture levels: 12.50, 15.00, 17.50 and 20.10% dry base (w.b). As moisture content increased from 10.50 to 20.10% (w.b), the average weight, major diameter, minor diameter, intermediate diameter, geometric mean diameter, arithmetic mean diameter of the seeds ranged from 0.35±0.08 to 0.60g±0.04g, 8.08±0.90 to 10.05±0.60mm, 4.04±0.53 to 5.00±0.10mm, 2.96±0.43 to 4.60±0.40mm, 4.52±0.45 to 6.03±0.20mm, 5.03±0.45 to 6.55±0.50mm respectively. Also the equivalent diameter, surface area, sphericity, projected area and aspect ratio of the seeds ranged from 4.75±0.42 to 6.03±0.41mm, 64.19±12.64 to 114.25±10.00mm2, 56±8.00 to 60±6.00%, 25.64±5.10 to 39.47 ± 3.80mm2, and 50±0.08 to 50±0.01mm respectively. The volume ranged from 0.35 ± 0.014 to 0.73 ± 0.014cm3, while the true and bulk densities ranged from 1.099 ± 0.141 to 1.110±0.424g/cm3 and 0.835±0.43 to 0.938±0.21g/cm3. Porosity decreased from 15.01±1.5 to 5.60±0.4% as moisture content increased from 10.50 to 20.10% (w.b). The angle of repose ranged from 39.80 to 60.10o with increase in moisture content. The optimum parboiling time, temperature and moisture content for hulling African breadfruit seeds were determined as 7.5minutes, 57.5oC and 20.10% (w.b) respectively. The terminal velocity of the seeds and kernels ranged from 12.5 to 17.02m/s and 11.40 to 13.36m/s. Drag coefficient and drag force of the hulls ranged from 0.1 to 0.7 and 0.518×10-4 to 0.858 ×10-4N, while the drag coefficient and drag force of the seeds and kernels ranged from 0.09 to 0.2, 4.50 ×10-4 to 6.00×10-4N; 0.2 to 0.3 and 4.0×10-4 to 5.10×10-4N respectively. This indicates that optimum separation can be achieved effectively without any loss of the seeds if the results obtained are properly applied in processing of African breadfruit.

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    DETERMINATION OF SOME PHYSICAL AND MECHANICAL PROPERTIES OF HORSE EYE BEAN (mucuna sloanei) FROM SOUTH EASTERN NIGERIA.

  • person_outlineAuthor(s): Eze PC, Eze CN
  • subjectCategory: Engineering
  • access_time19 June, 2017
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    Selected physical and mechanical properties of horse eye bean (mucuna sloanei) were studied at different moisture content levels of 11.5%, 13% and 17% (db). Compression strength characteristics were conducted under quasi-static compressive force at longitudinal and latitudinal (lateral) loading positions and the rupture forces, compressive strength, modulus of deformability, toughness, stiffness and force at bio-yield point determined as the mechanical properties. Results indicated that volume (20.137 - 21.856 mm3), surface area (598.362 - 720.208 mm2), geometric mean diameter (24.98 - 27.12 mm), and weight (7.625 - 9.203 g) of the velvet bean seed increased linearly with increase in moisture content. Also, the bulk density, specific gravity (0.378 - 0.421 g/mm3), sphericity (0.882 - 0.831) and aspect ratio (0.974 - 0.726) decreased linearly with increase in moisture content. These indicate that Velvet beans have wide size ranges and no single sample of the grains can effectively represent the other. In the case of the force-deformation characteristics, result indicates that the force and corresponding deformation to rupture of velvet bean seeds were found to vary from 400N - 2500N and 3mm - 10.25mm in longitudinal loading positions and 800N - 2800N, 3.5mm - 11.5mm  in lateral loading positions at the various moisture contents. The bio-yield force, compressive strength, stiffness and toughness of the velvet bean seeds varied from 400N - 1000N, 1.30N/mm2 - 8.03 N/mm2, 120N/mm - 833N/mm and 142.072 J/mm3 - 656.570 J/mm3 respectively in longitudinal loading positions to 600N - 2100N, 2.221 N/mm2 - 9.047 N/mm2, 57.14N/mm2 - 800 N/mm2 and 486.666 N/mm2 - 857.046 N/mm2 respectively in lateral loading position at the various moisture contents. Generally, the compressive strength of the horse eye bean seeds is higher at lateral loading position than at the longitudinal loading position.

  • library_books

    HYDROPROCESSING OF MICROALGAE OIL FOR GREEN DIESEL PRODUCTION

  • subjectCategory: Engineering
  • access_time18 December, 2016
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    This research was carried out to simulate microalgae oil hydroprocessing plant using ASPEN HYSYS simulation package. The simulation is based on conditions and parameters (temperature, pressure and catalyst selectivity) obtained from consulted literatures. After the successful completion of the simulation, total recovery of products for green diesel and propane was achieved as 85.6% and 4.01% (mass percentages) respectively. The green diesel composition indicated 0.01, 0.0005, 0.0201, 0.0757, 0.0021, 0.0089, 0.0041, 0.1813, 0.6822, 0.0191, and 0.005 mass fractions of n-C15, n-C16, n-C17, n-C18, n-C21, i-C15, i-C16, i-C17, i-C18, i-C21 and H2O respectively. The  quality specifications  of  the  simulated  Green  diesel  with  Cetane  number  86.7 fall within acceptable range and met the United State diesel standard  ASTM D975.  A complete disappearance of triglycerides in the product mixture at the hydrotreating temperature of 371 °C and pressure of 20 bar was observed. Economic analysis of the simulated project gives a total capital cost of ₦5.184billion, total production cost of ₦5.01 billion and cash flow as revenue of ₦6.02 billion after the fourth year. It shows that the project is highly profitable and efficient with a pay-back period of approximately 4years.

  • library_books

    MODELING SLOPE-ASCENDING SIGHT DISTANCE FOR OVERTAKING MANOEUVRE IN DOUBLE LANE HIGHWAY

  • subjectCategory: Engineering
  • access_time26 November, 2016
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    Many vehicles on the highway move at speeds below the design speed obviating overtaking maneuvers by vehicles that move at the design speeds. The paper is an attempt to formulate a model to determine the minimum overtaking sight distance to be maintained by the slope-ascending overtaking vehicle driver on an inclined double lane divided highway. The vehicle and road user characteristics as well as the vertical road geometry are combined to assess the overtaking distance by formulating a mathematical model that satisfies the laws of the mechanics of motion.

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    A MICROSWITCH BASED P.I.N DIODE SWITCH

  • subjectCategory: Engineering
  • access_time26 November, 2016
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    The behaviour of semiconductor devices at the microwave frequencies could be easily understood when the devices are represented by lumped networks. This paper has shown that the diode because of its smallness compared to the wavelength of the applied field could be used as a lumped element and the p-i-n diode serves as a good candidate for this purpose. The forward and reverse were seen to follow near normal diode characteristics bias impedences. The effect of insertion loss or minimum attenuation as well as impact of isolation on attenuation were  verified. These effects were tested on P-I.N diode for single and multiple throw  switches. The work showed that for two single switching circuits, there was minimum transmission coefficient of 0.94 at 3.2GHz and maximum of 0.11 at zero bias. For double switching grant, the minimum transmission coefficient was 0.92 with a maximum of 0.07. The isolation increase as the number of diodes increased, moving from 44db for double diode circuit to 53.9dB for three.

  • library_books

    INFLUENCE OF SCREEN SPEED AND AIR VELOCITY ON THE CLEANING EFFICIENCY OF A COWPEA ROTARY SCREEN CLEANER

  • subjectCategory: Engineering
  • access_time24 November, 2016
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    The influence of screen speed and air velocity on the cleaning efficiency of a rotary screen cleaner was investigated. The efficiency of separation of clean grain (xG) efficiency separation of material other than grain (xMOG) total cleaning efficiency    (xT) and percentage purity (%PP) were evaluated at air velocities of 0.3, 1.3, 2.2, 2.7 and 3.5 m/s and screen speed of 115, 145, 200, 280 and 315 rpm using two varieties of cowpea namely IT90K-277-2 and Ife brown. The results showed that xG decreased with increase in air velocity and screen speed while xMOG, xT and %Pp increased with increase in air velocity and screen speed for the two varieties. The highest values of xMOG, xT and %Pp for the two varieties were obtained at air velocity of 3.5 m/s and screen speed of 315 rpm.

  • library_books

    Physical and Mechanical Properties of Sorghum Grains (Sorghum Vulgare)

  • subjectCategory: Engineering
  • access_time22 November, 2016
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    The physical and mechanical properties of sorghum grains (sorghum vulgare) were studied at varying moisture contents of 13%, 20% and 30% (w.b). The four varieties of sorghum grains studied include; Dura, Guinea, Faterita and Kafir. Results indicate that the size ranges were 3.94mm - 4.83mm for Dura variety; 3.75mm - 4.54mm for Guinea variety; 3.21mm - 4.42mm for Kafir variety and 2.70mm - 4.14mm for Faterita variety. Irregularities in the shapes of the grains were observed but all approximated to a sphere. In the mechanical properties, at major diameter, Dura variety had highest rupture force of 1.16kN at 13% moisture content (w.b) while the Guinea variety had the lowest rupture force of 0.955kN. In minor diameter, the Dura variety also recorded highest rupture force of 1.12kN at 13% moisture content (w.b) while the Kafir variety had the lowest value of 0.952kN. Also at 20% moisture content, the Dura variety had highest rupture force of 1.025kN while the Guinea variety had the lowest rupture force of 0.965kN. The same trend applies in the varieties at 30% moisture content. This is because, increase in moisture content results to decrease in rupture force. And this implies that force beyond these points at these moisture contents may cause damage to the sorghum varieties.

  • library_books

    Physical and Frictional Properties of NERICA

  • subjectCategory: Engineering
  • access_time22 November, 2016
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    Some physical and frictional properties of the seeds and husks of New Rice for Africa (NERICA) were studied at varying moisture contents of 13%, 17%, and 20% (w.b). In the study, four varieties of NERICA namely; FARO 44, FARO 51, FARO 52 and FARO 57 were selected to represent the different size ranges common to NERICA. The physical properties of NERICA such as shape, size, volume, moisture contents, density, weights, surface area, aspect ratio and sphericity were obtained through physical measurement of the grains samples of each of the four varieties. Results of the physical measurements indicate that the size ranges for the varieties are as follows: FARO 44; 3.653mm to 3.858mm, FARO 51; 3.685mm to 3.916mm, FARO 52; 3.674mm to 3.863mm and FARO 57; 3.924mm to 4.019mm. Results of the frictional properties, shows that plywood material has the highest value of 28.4(1.36) = 33.0(1.41), 29.9(1.38) = 35.2(1.45) and 30.4(1.28) = 37.6(1.51) at 13%, 17% and 20% (w.b) respectively, while plastic material has the lowest coefficient of friction value of 20.8(1.21) = 17.7(1.14), 19.4(1.17) = 21.8(1.24) and 21.3(1.24) = 22.9(1.26) at 13%, 17% and 20% (w.b) respectively.

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