School of Physical Sciences (Phys-Sciences) Collection
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ItemComparing the effect of binder on the quality of bagasse briquettes(Makerere University, 2026)Briquettes made from biomass, such as sugarcane bagasse, a by-product of sugarcane mills, is a renewable energy source. This research aimed at the production and characterisation of bagasse briquettes. The major raw material, bagasse, underwent drying, size reduction, sieving, addition of molasses and clay (binder), densification using a manual press and finally drying of the briquettes. Physical and chemical parameters investigated include density, shatter resistance, calorific value, moisture content, volatile matter, ash content and fixed carbon. The results show calorific value of bagasse was 17.29MJ/kg, cowdung-binder briquettes was 15.92MJ/kg, molasses-binder briquettes was 16.49MJ/kg. The analysis revealed a composition of 47.49% carbon, 5.133% hydrogen, 1.557% nitrogen and 45.446% oxygen. Therefore bagasse has a high calorific value and can be used for briquetting to replace fossil fuels and firewood. In addition, due to its availability, utilizing it as a fuel source has an economic advantage.
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ItemCharacterization of microplastics from wastewater treatment plants in Kampala(Makerere University, 2025)This study aimed to evaluate the presence, types, and removal efficiency of microplastics (MPs) in wastewater treatment processes at Lubigi and Bugolobi Wastewater Treatment Plants (WWTPs) in Uganda. Wastewater samples were collected from both influent and effluent points across two sampling campaigns at each plant. Microplastics were characterized based on shape, revealing that beads, fragments and fibers were the most dominant types across all samples. Quantitative analysis indicated that Bugolobi WWTP achieved consistently high MP removal efficiencies, ranging from 87.24% to 95.93%, while Lubigi WWTP exhibited a wider range of performance, from 30.99% to 94.10%. This inconsistency at Lubigi suggests possible operational fluctuations or infrastructural limitations. Supporting physicochemical analyses showed reductions in turbidity, BOD, COD, and nutrient levels between influent and effluent samples, validating the general effectiveness of the treatment processes. The findings highlight the need for improved treatment infrastructure, regular monitoring, and policy-level attention to microplastic pollution in wastewater management systems.
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ItemProduction of carbonized briquettes from candlenut shells using unripe banana peelings as the binder(Makerere University, 2025)This study investigated the fuel characteristics and performance efficiency of biomass briquettes made from carbonized candlenut shells, in combination with an organic binder derived from boiled banana peels. These peels, typically considered agro-waste, were selected for their adhesive properties and environmental sustainability. Four distinct briquette samples were formulated, each characterized by a specific binder-to-char mass ratio: 0.24, 0.50, 0.75, and 0.80, which were chosen to evaluate the effect of increasing binder concentration on various physical and combustion-related properties of the briquettes. The samples underwent a series of standardized laboratory tests to determine their calorific value, moisture content, ash content, bulk density, mechanical durability, and drop resistance. The results revealed a consistent trend whereby increasing the binder proportion generally led to a decrease in calorific value and burning rate, attributed to the relatively lower energy density of the banana peel binder compared to the carbonized candlenut shell. However, higher binder content was positively correlated with improvements in mechanical durability, cohesion, and resistance to breakage, likely due to the enhanced binding effect and increased starch and fiber content from the boiled banana peels. Among the four samples, the briquette with a binder-to-char ratio of 0.50 demonstrated the most optimal balance between thermal efficiency and physical robustness, making it the most practical choice for domestic energy applications that require moderate heat output and reasonable handling strength. On the other hand, samples with higher binder ratios (0.75 and 0.80) exhibited longer ignition times and slower burning rates, characteristics that could be advantageous in scenarios requiring sustained heat release over extended periods, such as slow cooking or space heating
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ItemA Semiliki basin field study report(Makerere University, 2025)This report presents findings from fieldwork conducted in Uganda's Semliki Basin (Albertine Graben) from 30/06/2024 to 10/07/2024, analyzing stratigraphic, sedimentologic, and structural data critical for petroleum exploration. The basin, formed by tensional tectonics, contains Middle Miocene-Recent sediments overlying Jurassic/Permo-Triassic to Early Tertiary strata unconformably deposited on Precambrian basement (granite/gneiss/amphibolite). Lithologies include variably sorted sands (white/yellow), clays, polymictic/monomictic conglomerates, and siltstones showing cyclic fluvial-deltaic (coarsening/fining upward) and lacustrine (blocky) deposition. Paleocurrent analysis (Stereonet rose diagrams) suggests braided/meandering river systems, while gypsum/iron(III) minerals indicate semi-arid conditions. Stratigraphy comprises (ascending): Kisegi, Kasande, Kakara, Oluka, Nyaburogo, Nyakabingo, and Nyabusosi Formations. Structural analysis reveals NE-SW trending basement faults/joints (minor SE-NW trend) influencing sedimentary structures (cross-bedding, unconformities, mud cracks). Sempaya Hot Springs evidence active crustal thinning, providing sufficient thermal maturity (TTI) for hydrocarbon generation in Kasande Formation source rocks, with Kisegi Formation as reservoirs. Reservoir compartmentalization by thin clays/gypsum poses production challenges, while joints facilitate migration and normal faults create traps. The basin also shows significant geothermal potential.
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ItemReducing the rate of scaling in evaporators in the sugar making factories using anti-scalants(Makerere University, 2023)This research project was aimed at lowering the rate of scaling in the evaporators in the sugar manufacturing industries particulary SCOUL using anti-scalants. The significance of this research was to create a basis for the use of anti-scalants in inhibiting the scaling ions in the clarified cane juice. This was to lower the concentrations of the scaling ions particulary Ca 2+ and Mg 2+ present in the cane juice to undetectable limits which would greatly lower the rate of scale formation in the evaporators. This would help reduce the maintenance costs incurred by companies during clean-up of evaporators to remove the scales and it would also provide the company with more time to utilize for production since the clean-up sessions would be reduced as well. This analysis was limited to testing the removal of Calcium and Magnesium ions from the clarified cane juice using two anti-scalants of EDTA and polyacrylic acid. The clarified cane juice was sampled from the clarifier and the scale samples were obtained from the evaporators after a clean-up session. These samples were prepared and analysis was carried out on them to determine their composition. The scale inhibitors were purchased from Ramed Chemicals Limited in Kampala. The cation and anion compositions of the clarified cane juice and scale samples were identical and found to be Ca 2+ , Mg 2+ , SO 4 2- , PO 4 3- , C 2 O 4 2- , CO 3 2- , NO 3 2- . When the clarified cane juice was treated with EDTA, the Mg 2+ ions were completely inhibited but the Ca 2+ ions were not inhibited by the EDTA. When the clarified cane juice was treated with polyacrylic acid, the Mg 2+ ions were inhibited to some extent and the Ca 2+ ions were inhibited completely by polyacrylic acid. When the clarified cane juice was treated with a combination of EDTA and polyacrylic acid, both Mg 2+ and Ca 2+ ions were inhibited beyond detectable limits. In conclusion, the combination of EDTA and polyacrylic acid was effective in inhibing the scaling ions Ca 2+ and Mg 2+ .