Environmental Life Cycle Assessment of Sorghum (sorghum bicolor) Production, Storage and Disposal in Ilorin, Nigeria

Nigeria is one of the major producers of sorghum grains in the world. The production and storage of the crop consumed resources, both biotic and abiotic and this could lead to some environment burden in form of emissions and pollutions.  Therefore, this study was carried out to assess the environmental life cycle of sorghum, from production to storage and packaging for market using life cycle assessment model (LCA).The life cycle inventory data was collected for production, and storage operations of three scenarios of sorghum namely: storage in jute bags and fumigation in Warehouse (FW), usage of Bio-pesticide (BP) and NSPRIDUST (ND) as protectant. The inventory data collected was based on a functional unit of one hectare of land for production, and one ton of grains for storage operations respectively. The data were analyzed using “Ganzheitliche Bilanz” (GaBi) 8.7 software. Environmental impact categories generated were Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP), Ozone Depletion Potential (ODP) and Human Toxicity Potential (HTP).The GWP values obtained for sorghum scenario using FW, BP, and ND were 6.850, 7.930 and 6.890 kg CO2, respectively. The AP values for FW, BP and ND were 0.009, 0.012 and 0.009 kg SO2, respectively, while EP values obtained for FW, BP and ND were 2.180, 3.010 and 2.070 E-3 kg Phosphate, respectively. The ODP values using FW, BP and ND were 8.96, 8.96, and 8.96 E-13 kg R11 respectively, while the HTP values obtained using FW, BP and ND were 4.150, 4.150 and 4.150 kg DCB, respectively.The research showed that the impact values of FW, BP and NS for sorghum scenario had not much difference. The research finding is recommended for environmentalists, grain producers and handlers. Keywords: Life Cycle Assessment, global warming, acidification, eutrophication, ozone layer depletion DOI: 10.7176/JEES/12-8-01 Publication date:August 31st 202

ENERGY ANALYSIS AND ESTIMATION OF CO2 EMISSION OF SELECTED PLASTIC RECYCLING PLANTS IN NIGERIA

Energy management is a technical and management function which is to monitor, record, analyse, critically examine, alter and control energy flows through systems so that energy is utilized with maximum efficiency.  In line with this, a study was conducted in 4 randomly selected plastic recycling plants located in Osun and Oyo States in South West Nigeria.  The plants referred to as 1, 2, 3 and 4 in the study were investigated to determine the energy utilization patterns, estimate the CO2 emission and carry out exergy analysis.  The process analysis method of energy accounting was adopted to evaluate the energy requirement for each of the unit operations involved in the selected plants.  Investigation revealed that the types of energy used in the recycling plants were electrical, thermal and human labour with percent contribution of 7.14, 92.83 and 0.03% of the total energy in plant 1.  The corresponding values in the other plants were 87.81, 0, 11.9%; 22.44, 77.53, 0.03% and 8.12, 91.81, 0.06% respectively.  The total energy requirements for the four plants per tons of raw plastic wastes were 16.9, 0.5, 49.3 and 11.5 GJ respectively.  The amount of CO2 emitted in all the four plastic plants, which were mainly from the use of liquid fuels, were 76.8, 77.2, 74.5 and 90.6 tons of CO2 for 2005, 2006, 2007 and 2008 production years respectively.  The exergy analysis revealed that melting operation accounted for the highest exergy (available energy) in all the four selected plants. The results of this study have provided baseline data needed for monitoring energy utilization and policy making decision in the selected plastic recycling plants which could also find useful application in other similar plants in Nigeria

DESIGN AND CONSTRUCTION OF A METALLIC BIO-DIGESTER FOR THE PRODUCTION OF BIOGAS FROM COW DUNG

Biogas production has contributed greatly as an alternative source of fuel power to solving various developing nations’ problems including high dependency on petroleum products. This gives a clear objective why its production is seriously needed, as it plays a significant role in destroying and converting municipal and agricultural wastes into a useful fuel which can be used in homes and on farms for lighting, heating and moving equipment by supplying the fuel power needed This work focused on design and construction of a metallic bio digester for the production of biogas. Cow dung was mixed with water in ratio 1:2 of particulate mass. The experiment was carried out in a metallic digester under mesophilic temperature. The average retention time for the experiment was 30days. The average internal temperature of the biogas digester was 32.3oC. The total volume of biogas produced was 5.208 m3. The concentrations of methane and carbon dioxide in the biogas produced were found to be 59% and 40% respectively. The developed metallic bio-digester has been found to be appropriate for the production of biogas from cow dung at mesophilic temperature

EVALUATION OF A PEDAL – OPERATED CASSAVA GRATER

A pedal – operated cassava grating machine was developed and evaluated. The grater is to bridge the gap between the motorized grater and the labour-intensive, traditional cassava grating device, and to ameliorate the tedium of cassava grating at the village level. The grater’s component parts are: the grating unit, power and transmission unit, the housing, the hopper and the discharge chute. The cassava grater output capacity ranged between 28.50kg/h and 45.00kg/h depending on cassava variety. The particle size distribution in the end product representing medium fine, fine and powdery materials is 1:3:6. The grater capacity has a comparative advantage ratio of more than 220% over traditional grating device. One average person of between 25 – 45 years of age can comfortably operate the continuously for about 16 minutes to produce an output of about 4kg

Development and Evaluation of a Combined Castor Seed Roaster-Oil Expeller

This study evaluated optimal process parameters for mechanical oil expression from castor seeds after designing a castor seed roaster-expeller. The effect of input variables (Moisture Content at 6, 7, 8, 9 and 10% db; Roasting Temperature at 80, 90, 100,110 and 120oC and Applied Pressure at 15, 20, 25, 30 and 35 MPa) on the oil yield, expression efficiency, expression loss and energy used were determined using Central Composite Design in Response Surface Methodology for the optimization and modelling. Analysis of Variance was employed to determine the level of significance (P≤ 0.05). The optimum expression efficiency, expression loss and minimum energy used were 72.86%, 0.63% and 584.19 Watts obtained at experimental conditions of 15.00 MPa applied pressure, 6% moisture content and 85.52°C heating temperature respectively. The R2 values of the developed models ranged from 0.813 to 0.982 at 95% confidence level. The developed combined castor seed roaster-oil expeller was found to be efficient and developed models showed adequate prediction with good relationships between dependent and independent variables. Keywords: castor seed, oil extraction, modeling, optimization DOI: 10.7176/ISDE/11-1-07 Publication date: January 31st 2020

EXPLORING SOURSOP KERNEL AS A SUSTAINABLE BIOFUEL: ANALYZING PHYSICAL AND SOLID FLOW PROPERTIES FOR FEASIBILITY ASSESSMENT

  Soursop kernel is an oil-bearing seed containing about 25% non-edible oil per 100 g sample making it a potential feedstock for biofuel production. However, exploring the full potential of the oil requires data to design and fabricate appropriate machines for its processing. So, this necessitates a thorough examination of its physical and solid flow behaviour in relation to moisture contents. The experiments conducted on rewetted samples revealed that as moisture content (mc) increased from 8% to 32.5% dry basis (db), the length, width, thickness, arithmetic and geometric mean diameter, volume, surface area, sphericity, and thousand kernels weight increased from 11.40-12.06 mm, 7.04-7.92 mm, 4.58-5.34 mm, 7.69-8.44 mm, 7.12-7.49 mm, 6.5–8.13 cm3, 160.19-199.05 mm2, 0.62- 0.66 and 186.4–291 g, respectively. The true density decreased from 720 to 670 kg/m³, whereas the bulk density increased from 470 to 570 kg/m³. The angle of repose linearly increased from 25.8° to 39.2° as moisture content increased. The highest mean values for coefficients of friction were observed on mild steel surfaces (0.44 for static and 0.53 for dynamic) at 8.0% mc (db) while the lowest values were recorded on stainless steel surfaces (0.20 for static and 0.37 for dynamic) at both 32.5% and 8.0%, (mc, db). The data obtained will prove beneficial to engineers in the design and development of appropriate machines, as well as other handling and processing equipment such as oil expellers, so as to explore the full industrial application of the oil for biodiesel production and other chemical productio

LIFE CYCLE ASSESSMENT OF WHEAT PRODUCTION AND PROCESSING SYSTEM

Wheat being the leading source of vegetable protein in the human diets has higher protein content than other major staple grains or cereals like rice or maize; therefore it was necessary to study the environmental impacts associated with its field production and industrial processing using the life cycle assessment tool. The functional unit selected for the study was 1kg of wheat, and emission from various inputs into the system was aggregated into a large inventory table. Four environmental impacts were considered namely; global warming, acidification, eutrophication and ozone layer depletion. It was discovered that global warming has the highest impact score which is closely followed by eutrophication; 4.7153E – 02 kg CO2 equivalent and 3.5907E– 04kg NO3- equivalent respectively, while ozone layer depletion has the lowest environmental impact score of 1.1889E – 07 kg R11 equivalent. High emission of CO2 gas from fossil fuel during field operations and processing of wheat was observed as the reason for the high impact score of global warming

Energetic analysis of fruit juice processing operations in Nigeria

Abstract Energy and exergy studies were conducted in an orange juice manufacturing industry in Nigeria to determine the energy consumption pattern and methods of energy optimization in the company. An adaptation of the process analysis method of energy accounting was used to evaluate the energy requirement for each of the eight defined unit operations. The types of energy used in the manufacturing of orange juice were electrical, steam and manual with the respective proportions of 18.51%, 80.91% and 0.58% of the total energy. It was estimated that an average energy intensity of 1.12 MJ/kg was required for the manufacturing of orange juice. The most energy intensive operation was identified as the pasteurizer followed by packaging unit with energy intensities of 0.932 and 0.119 MJ/kg, respectively. The exergy analysis revealed that the pasteurizer was responsible for most of the inefficiency (over 90%) followed by packaging (6.60%). It was suggested that the capacity of the pasteurizer be increased to reduce the level of inefficiency of the plant. The suggestion has been limited to equipment modification rather than process alteration, which constitutes additional investment cost and may not be economical from an energy savings perspective.

Alkali-catalysed Laboratory Production and Testing of Biodiesel Fuel from Nigerian Palm Kernel Oil

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 9 (2007): Alkali-catalysed Laboratory Production and Testing of Biodiesel Fuel from Nigerian Palm Kernel Oil. Manuscript EE 07 00 9. Vol. IX. July, 2007