The ability to predict the quantity of energy to be produced is of paramount importance in every ... more The ability to predict the quantity of energy to be produced is of paramount importance in every country. It would assist in setting up a waste management plan which will lead to a sustainable energy policy. This paper presents the development of a statistical linear regression mathematical model to predict the amount of energy contained in municipal solid wastes from the knowledge of such characteristics of the wastes as physical composition and/or moisture content. Major cities of Kano, Katsina, Dutse, Damaturu, Maiduguri, Bauchi, Birnin Kebbi, Gusau and Sokoto in Northern Nigeria, with high population densities and intense industrial activities constituted the area of study. Ten kilogram each, of the municipal solid waste was collected from the government designated refuse dumping sites in both highly dense populated low income areas and government residential areas, during the hottest months of February, March and April and during the rainy season in the month of August for thre...
International Journal of Agricultural and Biological Engineering, 2014
Some physical, frictional and thermal properties of Brachystegia eurycoma seed were studied at di... more Some physical, frictional and thermal properties of Brachystegia eurycoma seed were studied at different moisture contents in order to explore the possibility of mechanizing the handling and processing techniques. Results showed that the seed could be considered an oval disc in shape. In the moisture range of 2.79% to 27.13% (d.b.), the major, intermediate and minor axial dimensions increased with increase in moisture content from 2.29 mm to 2.45 mm, 1.65 mm to 1.91 mm and 0.34 mm to 0.52 mm, respectively. In the above moisture range, one thousand seed weight, particle density, porosity, roundness, sphericity, surface area and angle of repose increased linearly from 0.901 kg to 1.252 kg, 2270 kg/m3 to 2520 kg/m3, 11.23% to 15.46%, 35% to 47%, 67% to 82%, 7.67 cm2 to 8.48 cm2 and 16.8° to 29.2° respectively, while bulk density decreased from 745.4 kg/m3 to 613.6 kg/m3. Static coefficient of friction on different structural surfaces increased linearly with moisture content and had the...
Agricultural Engineering International: The CIGR Journal, 2016
Application of reversible thermodynamic principles to gain fundamental understanding of food–wate... more Application of reversible thermodynamic principles to gain fundamental understanding of food–water interactions in foods has met with limited success due to the presence of moisture sorption hysteresis which is a manifestation of irreversibility. This study was aimed at understanding the nature and extent of influence of hysteresis on thermodynamic properties of two millet varieties namely EX-BORNO and SOSAT C88. Moisture sorption data (adsorption and desorption) in the water activity and temperature ranges of 0.07 – 0.98 and 30°C – 70°C, respectively were used. Ratio of latent heat of moisture sorption to the latent heat of pure water was determined using Clausius-Clapeyron equation. Effect of moisture content on ratio of latent heat of sorption to latent heat of pure water was determined using Gallaher model. Net integral enthalpy was determined at constant spreading pressure with monolayer moisture contents calculated using Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de ...
Brachystegia Eurycoma seed is an important food thickening agent with seed gum that has potential... more Brachystegia Eurycoma seed is an important food thickening agent with seed gum that has potential as binding agent in the pharmaceutical industry in Nigeria. Presently, the kernel is obtained by manually dehulling the seed and the operation is not only time consuming and tasky but also wasteful. In order to overcome the above problems associated with the processing of the seed, there is the need to development a mechanical device for handling and processing the crop. The development of such device requires knowledge of the mechanical properties of the seed. To provide the needed data, investigation of the mechanical properties of the seed under different processing conditions of soaking, parboiling and roasting and moisture content levels of 8.90, 14.02, 20.90 and 26.30% (w.b) was carried out using the Testometric Universal Testing Machine (UTM). The properties studied include bioyield point, yield point, rupture point, bioyield strength, compressive strength and rupture strength, m...
Energy and exergy analyses of native cassava starch drying in a tray dryer were carried out to as... more Energy and exergy analyses of native cassava starch drying in a tray dryer were carried out to assess the performance of the system in terms of energy utilization, energy utilization ratio, energy efficiency, exergy inflow and outflow, exergy loss and exegetic efficiency. The results indicated that for the starch with ash content of 0.76%, 0.85% crude protein, 0.16% crude fat, negligible amount of fiber, average granule size of 14.1 μm, pH of 5.88, amylose content of 23.45% and degree of crystallinity of 22.34%, energy utilization and energy utilization ratio increased from 1.93 to 5.51 J/s and 0.65 to 0.6 as the drying temperature increased from 40 to 60 °C. Energy efficiency increased from 16.036 to 30.645%, while exergy inflow, outflow and losses increased from 0.399 to 2.686, 0.055 to 0.555 and 0.344 to 2.131 J/s respectively in the above temperature range. Exergetic efficiency increased with increase in both drying air temperature and energy utilization and was lower than energy efficiency. Exergetic improvement potential also increased with increase in drying air temperature. Model equations that could be used to express the energy and exergy parameters as a function of drying temperature were established.
The desorption and adsorption equilibrium moisture isotherms of sorghum malt at the temperatures ... more The desorption and adsorption equilibrium moisture isotherms of sorghum malt at the temperatures of 40 and 50°C, over the water activity range of 0.1–0.9, were determined using the static gravimetric method. A non-linear regression programme was used to fit five moisture sorption isotherm models [Modified Henderson, Modified Chung-Pfost, Modified Guggenheim–Anderson–de Boer (GAB), Modified Halsey and Modified Oswin] to the experimental
The ability to predict the quantity of energy to be produced is of paramount importance in every ... more The ability to predict the quantity of energy to be produced is of paramount importance in every country. It would assist in setting up a waste management plan which will lead to a sustainable energy policy. This paper presents the development of a statistical linear regression mathematical model to predict the amount of energy contained in municipal solid wastes from the knowledge of such characteristics of the wastes as physical composition and/or moisture content. Major cities of Kano, Katsina, Dutse, Damaturu, Maiduguri, Bauchi, Birnin Kebbi, Gusau and Sokoto in Northern Nigeria, with high population densities and intense industrial activities constituted the area of study. Ten kilogram each, of the municipal solid waste was collected from the government designated refuse dumping sites in both highly dense populated low income areas and government residential areas, during the hottest months of February, March and April and during the rainy season in the month of August for thre...
International Journal of Agricultural and Biological Engineering, 2014
Some physical, frictional and thermal properties of Brachystegia eurycoma seed were studied at di... more Some physical, frictional and thermal properties of Brachystegia eurycoma seed were studied at different moisture contents in order to explore the possibility of mechanizing the handling and processing techniques. Results showed that the seed could be considered an oval disc in shape. In the moisture range of 2.79% to 27.13% (d.b.), the major, intermediate and minor axial dimensions increased with increase in moisture content from 2.29 mm to 2.45 mm, 1.65 mm to 1.91 mm and 0.34 mm to 0.52 mm, respectively. In the above moisture range, one thousand seed weight, particle density, porosity, roundness, sphericity, surface area and angle of repose increased linearly from 0.901 kg to 1.252 kg, 2270 kg/m3 to 2520 kg/m3, 11.23% to 15.46%, 35% to 47%, 67% to 82%, 7.67 cm2 to 8.48 cm2 and 16.8° to 29.2° respectively, while bulk density decreased from 745.4 kg/m3 to 613.6 kg/m3. Static coefficient of friction on different structural surfaces increased linearly with moisture content and had the...
Agricultural Engineering International: The CIGR Journal, 2016
Application of reversible thermodynamic principles to gain fundamental understanding of food–wate... more Application of reversible thermodynamic principles to gain fundamental understanding of food–water interactions in foods has met with limited success due to the presence of moisture sorption hysteresis which is a manifestation of irreversibility. This study was aimed at understanding the nature and extent of influence of hysteresis on thermodynamic properties of two millet varieties namely EX-BORNO and SOSAT C88. Moisture sorption data (adsorption and desorption) in the water activity and temperature ranges of 0.07 – 0.98 and 30°C – 70°C, respectively were used. Ratio of latent heat of moisture sorption to the latent heat of pure water was determined using Clausius-Clapeyron equation. Effect of moisture content on ratio of latent heat of sorption to latent heat of pure water was determined using Gallaher model. Net integral enthalpy was determined at constant spreading pressure with monolayer moisture contents calculated using Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de ...
Brachystegia Eurycoma seed is an important food thickening agent with seed gum that has potential... more Brachystegia Eurycoma seed is an important food thickening agent with seed gum that has potential as binding agent in the pharmaceutical industry in Nigeria. Presently, the kernel is obtained by manually dehulling the seed and the operation is not only time consuming and tasky but also wasteful. In order to overcome the above problems associated with the processing of the seed, there is the need to development a mechanical device for handling and processing the crop. The development of such device requires knowledge of the mechanical properties of the seed. To provide the needed data, investigation of the mechanical properties of the seed under different processing conditions of soaking, parboiling and roasting and moisture content levels of 8.90, 14.02, 20.90 and 26.30% (w.b) was carried out using the Testometric Universal Testing Machine (UTM). The properties studied include bioyield point, yield point, rupture point, bioyield strength, compressive strength and rupture strength, m...
Energy and exergy analyses of native cassava starch drying in a tray dryer were carried out to as... more Energy and exergy analyses of native cassava starch drying in a tray dryer were carried out to assess the performance of the system in terms of energy utilization, energy utilization ratio, energy efficiency, exergy inflow and outflow, exergy loss and exegetic efficiency. The results indicated that for the starch with ash content of 0.76%, 0.85% crude protein, 0.16% crude fat, negligible amount of fiber, average granule size of 14.1 μm, pH of 5.88, amylose content of 23.45% and degree of crystallinity of 22.34%, energy utilization and energy utilization ratio increased from 1.93 to 5.51 J/s and 0.65 to 0.6 as the drying temperature increased from 40 to 60 °C. Energy efficiency increased from 16.036 to 30.645%, while exergy inflow, outflow and losses increased from 0.399 to 2.686, 0.055 to 0.555 and 0.344 to 2.131 J/s respectively in the above temperature range. Exergetic efficiency increased with increase in both drying air temperature and energy utilization and was lower than energy efficiency. Exergetic improvement potential also increased with increase in drying air temperature. Model equations that could be used to express the energy and exergy parameters as a function of drying temperature were established.
The desorption and adsorption equilibrium moisture isotherms of sorghum malt at the temperatures ... more The desorption and adsorption equilibrium moisture isotherms of sorghum malt at the temperatures of 40 and 50°C, over the water activity range of 0.1–0.9, were determined using the static gravimetric method. A non-linear regression programme was used to fit five moisture sorption isotherm models [Modified Henderson, Modified Chung-Pfost, Modified Guggenheim–Anderson–de Boer (GAB), Modified Halsey and Modified Oswin] to the experimental
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