DSpace Repository :: Browsing by Author "Asere, A. A."

Browsing by Author "Asere, A. A."

Now showing 1 - 11 of 11

Co-pyrolysis of cassava peel with synthetic polymers: thermal and kinetic behaviors
(Waste Disposal & Sustainable Energy, 2021-06-24) Adeboye, B.S.; Adewole, B. Z.; Adedoja, A. M.; Obayopo, S. O.; Mamuru, S. A.; Idris, M. O.; Okediran, I. K.; Asere, A. A.
This research effort focuses on the co-pyrolysis of cassava peels waste and some synthetic polymers towards energy conversion and reducing the volume of these waste fractions dumped on dumpsites. The co-pyrolysis behavior and pyrolysis kinetics of various synthetic polymer wastes/cassava peel blends were investigated by blending cassava peel waste with low-density polyethylene (LDPE), polyethylene terephthalate (PET), and polystyrene (PS) at different weight ratios. The physical characteristics of each sample were investigated and the co-pyrolysis experiments were conducted at a heating rate of 10 °C/min from room temperature to 800 °C in N2 atmosphere in a thermogravimetric analyzer. Subsequent to thermal decomposition, kinetic analysis was done using the thermogravimetric data. Results from physicochemical characterization showed that cassava peel has a relatively lower calorific value of 15.92 MJ/kg compared with polystyrene (41.1 MJ/kg), low-density polyethylene (42.6 MJ/kg), and polyethylene terephthalate (21.1 MJ/kg). The thermal decomposition behavior of cassava peel was seen to be significantly different from those of the synthetic polymers. The decomposition of the biomass material such as cassava peel generally occurs in two stages while the decomposition of LDPE, PS, and PET occurred in a single stage. The activation energy required for thermal degradation in cassava peel was also found to be lower to that of the plastic material. The co-pyrolysis of cassava peel and different synthetic polymers affected the thermal and kinetic behaviors of the blends, reduce the activation energy and residue after pyrolysis.
A Comparative Performance and Emission Analysis of Blended Groundnut Oil and Mineral Oil Based Lubricants Using a Spark Ignition Engine
(The CIGR E journal Manuscript, 2008-09) Ejilah, I. R; Asere, A. A.
This paper presents the performance and emission behaviour of a spark ignition engine run on groundnut oil blended lubricants. However, for the purpose of comparism, benchmark tests were carried out on multigrade and monograde motor oils. A 5.0 h.p engine test-bed incorporated with an A.C dynamometer and flue gas analyzer was used to conduct the tests. At maximum engine speed, the groundnut oil blended lubricants generated an exhaust temperature of 6.02% higher than multigrade oil, and 6.26% higher than monograde oil. The brake power was 12.70% and 10.94% higher than the monograde and multigrade oils. In terms of fuel economy, the monograde and groundnut oil blended lubricants are 7.50% and 2.18% higher than multigrade oil respectively. It is shown that as the proportion of viscosity modifier in the oil sample increases, exhaust temperature, brake power, brake mean effective pressure (b.m.ep) also increases, while the specific fuel consumption diminishes. At various speeds, CO2 level emitted by the use of groundnut oil blended lubricants was observed to be higher than it was the case for multigrade and monograde oils. In the light of the fast depleting fossil fuel reserve in Nigeria, this work has demonstrated the feasibility of using groundnut oil blends as lubricant substitutes in spark ignition engines.
A Comparative Performance and Emission Analysis of Blended Groundnut Oil and Mineral Oil Based Lubricants Using a Spark Ignition Engine.
(Agricultural Engineering International: The CIGR E journal Manuscript EE 07017., 2008-09) Ejilah, I. R; Asere, A. A.
This paper presents the performance and emission behaviour of a spark ignition engine run on groundnut oil blended lubricants. However, for the purpose of comparism, benchmark tests were carried out on multigrade and monograde motor oils. A 5.0 h.p engine test-bed incorporated with an A.C dynamometer and flue gas analyzer was used to conduct the tests. At maximum engine speed, the groundnut oil blended lubricants generated an exhaust temperature of 6.02% higher than multigrade oil, and 6.26% higher than monograde oil. The brake power was 12.70% and 10.94% higher than the monograde and multigrade oils. In terms of fuel economy, the monograde and groundnut oil blended lubricants are 7.50% and 2.18% higher than multigrade oil respectively. It is shown that as the proportion of viscosity modifier in the oil sample increases, exhaust temperature, brake power, brake mean effective pressure (b.m.e.p) also increases, while the specific fuel consumption diminishes. At various speeds, CO2 level emitted by the use of groundnut oil blended lubricants was observed to be higher than it was the case for multigrade and monograde oils. In the light of the fast depleting fossil fuel reserve in Nigeria, this work has demonstrated the feasibility of using groundnut oil blends as lubricant substitutes in spark ignition engines.
DETERMINATION OF HEAT TRANSFER PROPERTIES OF VARIOUS PVC AND NON-PVC CEILING MATERIALS AVAILABLE IN NIGERIAN MARKETS
(International Journal of Mechanical Engineering and Technology (IJMET), 2018-08) Oyekunle, J. A. O.; Dirisu, J. O.; Okokpujie, I. P.; Asere, A. A.
In this study, heat transfer properties of 10 polyvinyl chloride (PVC) ceiling composites and 4 other non-PVC ceiling materials, such as particle board, cardboard, plywood and asbestos were determined using an automated Lee’s disc apparatus and XRY-1C bomb calorimeter. Results obtained indicated that asbestos were consistent in being inert to ignition in addition to having the lowest specific heat capacity (SHC). Polyvinyl chloride ceiling composites had advantageous thermal conductivities in comparison to the non-PVC ceiling materials. The SHCs and thermal characteristics of ceiling materials for building constructions and other applications should be appraised by manufacturers where combustion requirements are of utmost consideration.
Development of a bench-scale fluidized bed combustor (FBC) for coal and biomas combustion
(Federal University of Technology, Minna, Niger State, Nigeria., 2015-03) Popoola, O. T.; Adio, S. A.; Oke, A. O.; Asere, A. A.
The high technological level of equipment for combustion of fuels, as well as the necessity for rational and efficient use of non-renewable energy resources, has resulted demanding requirements that must be fulfilled by equipment for energy production, via combustion. These requirements form the characteristics of Fluidized bed Combustor (FBC). The objective of this work is to design and fabricate a Circulating FBC for the combustion of coal and biomass and present the design criteria considered in the combustion process. The Designed FBC was then tested by combusting coal (Lafia Obi) and biomass (coconut shell) using the relevant ASTM guidelines. For coal combustion, the characteristic quantities measured from the bench-scale fluidized bed combustion include a mean NOx emission of 455.35, 376.69, 323.35 and 277.35 ppm for a coal feed size of 10, 15, 20 and 25 mm respectively. NOx emission from the combustion of coconut shell in fluidized bed is low and further reduced by the introduction of secondary air. Secondary air increases the recoverable energy level from this biomass, while average CO emission was 13,080 16,620 17,040 and 19,140 ppm for a coal feed size of 10, 15, 20 and 25mm. The temperature in the fluidized bed at ≥ 1100oC was sustained.
Effects of Emission Characteristics on Elemental Composition of Selected PVC Ceiling Materials
(American Scientific Publishers : Materials Focus, 2018) Dirisu, J. O.; Oyedepo, S. O.; Fayomi, O. S. I.; Okokpujie, I. P.; Asere, A. A.; Oyekunle, J. A.; Afolalu, S. A.; Abioye, A. A.
This research work determined the emission characteristics and elemental composition of selected PVC ceiling materials common in Nigerian markets especially during service. This research work determined the emission characteristics and elemental composition of selected PVC ceiling materials common in Nigerian markets. The emission data and elemental structure gave insight to appraise their suitability as ceiling materials. Three PVC ceiling materials were used for this analysis: Nigerian made PVC, layered Composite PVC and white PVC. Rutherford Backscattering Spectrometry (RBS) was performed to obtain the elemental structure of the ceiling materials using Ion Beam Analysis facility. 0.05 kg of the samples were combusted in a controlled fire chamber and the gasses emitted; CO, SO2, NO, and volatile organic compounds (VOC) were identified using four gas analyzers. Elements were detected in total and data collected from the experiment were analyzed. Results showed that Nigerian made PVC has the highest total noxious gas among the three samples with value of 3732.5 ppm while layered composite PVC has the lowest among the PVCs with the value of 1477.5 ppm. The elemental make-ups of the samples influence their emission characteristics. The study established that PVC samples were noxious in terms of their emission characteristics due to the effects of their elemental basis.
Effects of Soybean Methyl Ester on the Performance Characteristics of Compression Ignition Engine
(World Academy of Science, Engineering and Technology International Journal of Mechanical and Mechatronics Engineering, 2014) Fasogbon, S. K.; Asere, A. A.
Depletion and hazardous gas emissions associated with fossil fuels have caused scientists and global attention to focus on the use of “alternative, eco-friendly substitutes for use in Compression Ignition Engines. In this work, biodiesel was produced by trans-esterification of soybean obtained from a Nigerian market using Sodium Hydroxide (NaOH) as a catalyst.” After the production, the physical properties (specific gravity to kinematic viscosity and net calorific value) of the Soybean-biodiesel produced and petrol diesel obtained from a filling station in Nigeria were determined, and these properties conform to conventional standards (ASTM). A cummins-6V-92TA DDEC diesel (Compression ignition, CI) engine was run on various biodiesel-petrol diesel blends (0/100, 10/90, 20/80, 30/70 and 40/60), the B20 (blend 20/80) was found to be the most satisfactory.
ENERGY OUTPUT ASSESSMENT OF LAFIA-OBI COAL IN A FLUIDIZED BED COMBUSTOR
(Faculty of Engineering, University of Nigeria, Nsukka : Nigerian Journal of Technology (NIJOTECH), 2018-10) Ilyas, E. O; Adewole, B. Z.; Adio, S. A.; Popoola, O. T.; Asere, A. A.
This work investigated the energy output from the fluidized bed combustion of Lafia-Obi coal using five range of fuel equivalent diameters (FED) of 125 μm, 250 μm, 355 μm, 2.5 mm and 5.0 mm. Energy output in response to variation in bed temperature, FED, bed pressure, and fluidizing velocity was examined in the fluidized bed heat exchanger. Results indicated an increase in heat transfer rate by 80, 11 and 25% when 5 mm coal was reduced to 355, 250 and 150 μm respectively. Bed temperature increased by 8% for 355 μm and decreased by 6% when 5.0 mm coal was fired. Higher bed pressure was observed when larger particle sizes (5.0 and 2.5 mm) were fired. This resulted in poor bed temperature and increasing fluidization velocity and thus, reduced steam discharge temperature at the heat exchanger outlet.
INFLUENCE OF TEMPERATURE DIFFERENCE (WATER-COVER SURFACE) ON THE PERFORMANCE OF A COMPACT HEMISPHERICAL SOLAR STILL
(Faculty of Engineering, University of Nigeria, Nsukka : Nigerian Journal of Technology (NIJOTECH), 2020-07) Adewole, B. Z.; Arabambi, A. E.; Asere, A. A.
The study investigated the influence of temperature difference (ΔT) between evaporative and condensing surface temperature on water productivity of hemispherical solar still. The still was developed, tested and evaluated under the climatic conditions of Ile-Ife, Nigeria, to obtain an average distillate yield per hour per day for different combination of basin temperature, water temperature, transparent cover temperature, ambient temperature and solar intensity. Results indicated a decrease in the hourly water yield as (ΔT) increases. Regression analysis revealed that ΔT has no significant influence on the hourly water yield (P > 0.05). Maximum water productivity was obtained for a low condensing surface temperature and a high evaporative surface temperature. The study concluded that the improvement on water productivity of solar still can be achieved by enhancing the evaporative and condensing surface temperature. Methods for obtaining higher evaporating temperature should be sought in order to boost water productivity of solar stills.
PARABOLIC SOLAR COOKER DISH: DESIGN AND SIMULATION
(Solar Energy Society of Nigeria (SESN), 2011) Dasin, D. Y.; Asere, A. A.; Habou, D.
ABSTRACT A complete design and simulation of a parabolic dish solar cooker was carried out. The cooker can be used for boiling water as well as cooking in an isolation. A simulation model for transient state was introduced to predict the absorber (cooking pot), pot cover, cooking fluid and air gap temperatures. Linear regression was used to analyzed the data, an average standard error limit of 12.458345% and R2of 85.725% for the model was obtained which indicate a satisfactory agreement by comparison of experimental and theoretical result. An average instantaneous efficiency of 84% was determined at beam radiation of 650W/m2.
Thermal Performance of a Reflector Based Solar Box Cooker Implemented in Ile-Ife, Nigeria
(International Journal of Energy Engineering, 2015) Adewole, B. Z.; Popoola, O. T.; Asere, A. A.
Different categories of solar cooker ranging from concentrator types, solar ovens, box type cookers with or without reflectors and indirect solar cookers have been designed and tested in Nigeria. The uses of different designs of solar cookers have not become acceptable in the rural areas due to number of reasons. It is either they are too expensive for individual family to afford or they are yet to be practically known. In view of these shortcomings, this paper presents thermal performance of low cost reflectors based solar box cooker implemented in Ile-Ife, Nigeria. The cooker was constructed with locally available materials. The thermal performance of the cooker in terms of figures of merits and cooker efficiency was evaluated based on Indian Standard (IS 13429:2000). Results of field evaluation show maximum insolation of 520 W/m2 at 2.00 pm and minimum of 246 W/m2 at 11.00 am. The average solar radiation and ambient temperature observed during the test periods were 403 W/m2 and 40°C respectively. The water temperature values between 60 and 67°C were observed at insolation values between 398 and 520 W/m2. These occur between the hour of 1:20 pm and 4:00 pm with the highest water temperature of 67°C at 3.00 pm. The performance of the cooker in terms of first figure of merit, second figure of merit and thermal efficiency show that the cooker compare favourably well with international standard. The cooker has a better heat retention capacity when compared with others found in the literature. The experimental results obtained for thermal performance of the cooker demonstrated its suitability for cooking even during fluctuating weather conditions.

Browsing by Author "Asere, A. A."

Results Per Page

Sort Options