Freddie L. Inambao

Hybridization of feedstocks—A new approach in biodiesel development: A case of Moringa and Jatropha seed oils

ABSTRACT In this study, two selected feedstocks, Moringa oleifera and Jatropha curcas seed oils, and their methyl esters (biodiesel) were subjected to two new different hybridization processes at varying proportions experimentally. The hybrid compositions were J50M50, J40M10, J30M20, J20M30, and J10M40 from crude oil samples (in situ) and BM50J50, BM40J10, BM30J20, BM20J30, and BM10J40 from produced biodiesel by transesterification (ex situ) using production variables and optimization sequences. The hybrids were evaluated for chemo-physical and thermal properties using American Society for Testing and Materials and South African National Standards standards for each specific test(s). Results obtained revealed the efficacy of hybridization in improving the specific biodiesel properties as fuels. Specific tests include viscosity, specific gravity, refractive index, cetane index, fatty acid composition, free and total glycerine (TG), free fatty acid (FFA) composition, flash point, pour and cloud points, and calorific values. These were all higher and better than the single-stock biodiesel fuels. Moringa oleifera biodiesel, which was proved an excellent biodiesel fuel in the previous studies of the authors having high oleic acid content (>70%), impacted positively on Jatropha in enhancing its potential, with positive correlation at a 95% confidence level (α > 0.05) and on analysis of variation (ANOVA). This is a new approach in biodiesel development as studies of this nature are scarce in the literature.

Centrifugal casting technique baseline knowledge, applications, and processing parameters: overview

Abstract The increasing need for materials with light weight, high resistance to corrosion and wear, toughness and strength, machinability, high thermal capacity etc. for various applications is unending. This demand has continued to stretch the exploitation and manipulation of various functionally graded materials (FGMs) and their production methods. This study explores one of the FGM production processes called the centrifugal casting technique (CCT). The centrifugal casting process has several potential advantages over traditional casting methods. This study provides information regarding the basic functionally graded production methods and their applications and also discusses categories of CCT, evolution and process parameters.

Principles and Baseline Knowledge of Functionally Graded Aluminium Matrix Materials (FGAMMs): Fabrication Techniques and Applications

This paper discusses the main Functionally Graded Materials (FGMs) and their bulk fabrication techniques, their development, principles and applications. The fabrication processes considered include powder metallurgy (PM), sintering, squeeze casting, infiltration process, compocasting, centrifugal casting, stir casting, material prototyping. The paper provides an overview of the FGM processing parameters including reinforcement particles size and volume %, temperature, pressure (for PM), and stirrer and mould rotational speeds (for stir and centrifugal casting processes respectively). The paper notes that the FGMs are widely used in the following sectors: automotive, medical, aerospace, aviation, nuclear energy, renewable energy, chemical, engineering, optics electronics etc.

Design basics of a small hydro turbine plant for capacity building in sub-Saharan Africa

This paper presents a simplified design considerations for a propeller hydro-turbine, including tabulated relevant mathematical expressions of operating parameters. In the design calculation, a 2.5 m head and 0.183 m3/s flow rate were used as river data for power of 2.61 kW. A four-blade propeller with an outer diameter of 0.226 m and a hub diameter of 0.079 m was considered suitable for the low head application. Dimensionless performance parameters for various power (2–10 kW) and flow rate (0.2–0.6 m3/s) were evaluated (using constant head and rotational speed), the results were tabulated and graphs plotted. The static axial force on the blade and hub analysis was carried out and results shown satisfactory performance of aluminum 6061-T6 alloy as the blade material. Popularisation of small hydro power (SHP) design and production technology in sub-Saharan Africa through domestic capacity building will accelerate local fabrication of SHP plants and components. The study recommends that the design process be based on available materials and manufacturing facilities. The provision of SHP for rural areas, industrial estates and standalone electrification will provoke commercial and industrial activities in sub-Saharan Africa. This will consequently raise the productivity and the standard of living of the people.

Reducing infrasound and low frequency noise from windturbine blades and rotors using ANC

Abstract nThe paper constitutes an application of Active Noise Control (ANC) on noise from wind turbine blades and n rotors. This study aims at considering the potential of using ANC on wind turbines. To this end, a review n was

Solar Energy as an Alternative Energy Source to Power Mobile Robots

Solar energy can provide a viable alternative energy source to meet the special energy demands that are typically required to operate mobile robots. Conventional energy sources cannot fulfil these demands as satisfactorily as solar energy can, given the disfavour that conventional energy sources find in an eco-conscious world, and also given the practical limitations associated with conventional energy sources which cannot conveniently be accessed in places where mobile robots are normally put to use which are often inaccessible and beyond human reach. This study seeks to demonstrate that solar energy can be harnessed and stored using hydrogen as a medium to store an otherwise intermittent supply of energy that is characteristic of solar energy. In this study, an Industrial Mobile Robot Platform (IMRP) was designed to run on fuel cells using a low-pressure metal hydride hydrogen storage system which would store more energy on board than a rechargeable battery could.

Energy sustainability through domestication of energy technologies in third world countries in Africa

Access to reliable and adequate energy is a compulsory step to industrialization, improving the living standards of the people, enhancing safety and security, and preserving a healthy environment. Energy plays a fundamental role in shaping and reshaping of the human condition and is therefore essential for human survival and a major factor for economic growth. There is a strong correlation between socio-economic development and the availability of electricity. The third world countries are faced with chronic electricity problems, which are hindering economic developmental programmes, notwithstanding the availability of vast natural resources in these countries. This paper sees and discusses over dependence of foreign energy production technologies, expatriates for operation and maintenance of power facilities as major failure of energy infrastructural growth and consequent inhibitor of economic growth. It went further to suggest capacities building in the area of renewable energy especially design and fabrication of small hydro power (SHP) facilities (parts and systems) and their production technologies as a key for better energy delivery for third world countries in African economic growth.

Electricity insufficiency in Africa: A product of inadequate manufacturing capacity

Energy availability is fundamental and crucial for human survival and for national economic development. Energy consumption per capita of a country or region is a measure of quality of life and industrialisation of a country or region. This to certain extent explains why energy consumption is higher in technologically developed countries than the developing ones. Africa is faced with chronic power problems and this stalls her economic growth, in spite of availability of vast natural resources in the region. The number of Africans without access to modern energy is over 600 million and the projected year of adequate power accessibility in Africa is 2080. This study shows that the main hindrances to access to power in Africa are insufficient continental collective effort, inadequate application of academic based research findings, inadequate manufacturing infrastructure and overdependence on foreign technology, insufficient human capacity development and the high cost of power projects in the region. The study went further to identify small hydropower plant (SHP) technology capacity building to facilitate domestication, establishment of regional energy research institutions, transformation of research findings into real products, and adoption of Asian developing countries’ energy development approach as formidable ways of tackling power problems and power sustainability in Africa.

Performance and emission evaluation of pure biodiesel from non-edible feedstock and waste oil in a diesel engine

Biodiesel prepared from Jatropha, Moringa and restaurant waste oil were evaluated in a 3.5u2005kw diesel engine to determine their performance and pollutant emission. The brake specific (BS) emissions across the full load spectrum were benchmarked against the United States Environmental Protection Agency (US, EPA) and the European Union (EU) emission caps. Results showed that the brake specific fuel consumption (BSFC) and brake thermal efficiencies gave marginal differences between conventional diesel fuel (ndiesel) and the biodiesel fuel samples (±4% and ±5 respectively at peak load). Carbon monoxide (CO), unburnt hydrocarbon (UHC) and particulate matter (PM) emissions (in parts per million) showed a decreasing trend with load increase and were lower than those of ndiesel fuel samples. Oxides of nitrogen (NOX) emission for the biodiesel were observed to be lower than those of ndiesel. This was because the 1650u2005k peak temperature to activate thermal NOX was sparingly breached for the biodiesels. BSHC for all fuel types failed the EPA as well as the EU emission caps under all loading conditions. All tested fuel samples met the regulatory standards at load conditions exceeding 65%. Brake specific particulate matter (BSPM) for all fuel type fell short of the EPA and EU standard, except those of waste oil and jatropha biodiesel, with BSPM below the EU upper limit of 0.85 g/Kwh.

A property prediction scheme for biodiesel derived from non-edible feedstock

Biodiesels renewability, universal accessibility and milder impact on the environment has positioned it as a potential fuel of choice for transport prime movers going forward. Biodiesels unique fuel chemistry while conferring some advantage, has shown some mismatch between it and the current compression ignition (CI) combustion strategy. Computational as well as experimental research on biodiesel combustion are presently, in large part, geared toward resolving this mismatch. Numerical property prediction, as a more efficient and cost effective tool was implemented here to determine the thermo-physical and transport properties of biodiesel derived from moringa, jatropher and waste restaurant oil. Primary and secondary experimental data obtained in accordance with biodiesel standard ASTM D6751 were used to validate the scheme. The average relative deviation (ARD) for most key properties fell within acceptable limit (≤5%). Obtaining higher computational fidelity was observed to correlate with improved accuracy in determining the free fatty acid (FFA) composition of the different component and group contribution of the biodiesel mixture.