Browsing by Author "Ziwu, C."
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Item Feasibility study for biogas integration into waste treatment plants in Ghana(Egyptian Journal of Petroleum, 2017-09) Mohammed, M.; Egyir, I.S.; Donkor, A.K.; Amoah, P.; Nyarko, S.; Boateng, K.K.; Ziwu, C.Biogas (anaerobic digestion) technology is one of the most viable renewable energy technologies today. However, its economic efficiency depends on the investment costs, costs of operating the biogas plant and optimum methane production. Likewise the profit level also rests on its use directly for cooking or conversion into electricity. The present study assessed the economic potential for a 9000 m3 biogas plant, as an alternative to addressing energy and environmental challenges currently in Ghana. A cost-benefit analysis of the installation of biogas plant at University of Ghana (Legon Sewerage Treatment Plant) yielded positive net present values (NPV) at the prevailing discount rate of 23%. Further the results demonstrate that installation of the plant is capital intensive. Biogas used for cooking was by far the most viable option with a payback period (PBP) of 5 years. Sensitivity analysis also revealed cost of capital, plant and machinery as the most effective factors impacting on NPV and internal rate of return (IRR). © 2016 Egyptian Petroleum Research InstituteItem Leaching of trace metals from mixed electronic waste using four extraction methods(Science and Development, 2017) Donkor, A.; Owusu, G.; Banson, S.A.; Ziwu, C.; Bonzongo, J.; Nyarko, S.; Tawiah, R.; Asante, I.; Nyame, F.Rapid developments in technology in recent times, coupled with increasing demands for electronic products, have led to a rapid increase in electronic waste (e-waste) in the environment. The leaching of metals from e-wastes into the environment is a potential health and environmental hazard. The present study investigates the leaching potential of fourteen metals (Ag, Al, As, Ca, Cd, Cr, Cu, Fe, K, Mg, Na, Ni, Pb and Zn) in mixed waste printed circuit boards (PCBs) and plastic housing (PH) from recycling/dump sites. The assessment was carried out using rain water, deionized water, synthetic precipitation leaching procedure (SPLP) solution and seawater over a period of 192 hours at regular intervals. The data obtained was compared to TCLP and WET limits. The toxicity characteristic potential of the elements extracted by these solvents were in the order deionized water>rainwater>SPLP>seawater. The levels of the 14 elements studied were generally low and in varying concentrations, with Ca, K, Mg and Na being relatively higher in all the leaching fluids. The results further proved that leaching from PCBs and PH was a significant source of trace metals from recycling/dump sites. Therefore, proper handling and disposal of these waste materials should be encouraged to lessen their impact on the environment.Item A novel approach for reduction of total acidity in kerosene based on alkaline rich materials readily available in tropical and sub-tropical countries(Egyptian Journal of Petroleum, 2016-12) Donkor, A.; Nyarko, S.; Asemani, K.O.; Bonzongo, J.-C.; Kyeremeh, K.; Ziwu, C.The inability of refineries in some nations globally to produce kerosene locally as an aviation fuel is due to its acidity. In this study the viability of selected alkaline rich ash materials (e.g. cocoa husk, cassava peels, etc.) readily obtainable in tropical nations were examined for their ability to remove the acids. Fresh acidic kerosene samples were equilibrated with different ashes in predetermined ratios, filtered and characterized alongside with non-treated reference samples. Results revealed that the physicochemical properties of non-treated and treated kerosene remained the same except for conductivity, total acidity and micro-separation. The total acidity was reduced to a lowest limit than 0.015 mg KOH/g required. Treatment studies with specific masses of ashes and kerosene reduced acidity to approximately 0.00 mg KOH/g. Overall these alkaline source materials should be seen as a promising and alternative option in the systematic reduction of acidity in kerosene for aviation use. © 2015Item Public Perception of E-Waste Management and Disposal Practices in Accra Metropolis, Ghana(Science and Development, 2017) Owusu, G.; Donkor, A.; Ziwu, C.; Nyarko, S.; Bonzongo, J.; Dubey, B.; Asante, I.; Nyame, F.The electrical/electronic industry is one of the fastest growing sectors in the world today. The increasing demand for newer electrical/electronic equipment and the shorter lifespan of these products leads to the generation of large volumes of e-wastes (electrical and electronic wastes) in the environment. Unlike the developed nations, there is lack of public awareness and proper legislation to effectively manage these wastes in most developing nations, including Ghana. In this study, a survey was carried out on 800 respondents to determine their knowledge of e-waste management practices and the effects on humans and the environment. The results generally revealed a low level of awareness, with most participants showing little or no interest in their environment. The majority of respondents identified reselling and recycling of used electrical and electronic equipment (UEEE) as the most appropriate and safe disposal methods. There was a correlation between level of education and knowledge of: (i) toxic chemicals in e-waste, (ii) human health and environmental impact and (iii) disposal methods for e-waste using a Chi-square test, a fact emphasized by Principal Component Analysis (PCA). Thus, there is the need for programmes to educate and create general awareness for this class of wastes as a potential source of pollutants.