Department of Chemical and Process Engineering
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Item Technical evaluation and beneficiation of Ugandan silica sands for solar glass and photovoltaic-grade silicon production.(Busitema University, 2026) Omuria, GodfreyThe growing demand for high-purity silica in photovoltaic applications has created a need to evaluate local silica resources for solar glass and silicon feedstock production. This study assessed the suitability of selected Ugandan silica sand deposits for these applications through systematic chemical, mineralogical, and physical characterization combined with sequential beneficiation. The specific objectives were to determine the chemical composition of the silica sand, quantify improvements in silica purity and iron removal after beneficiation, analyse mineralogical characteristics, and evaluate particle size distribution and morphological properties. Silica sand samples were subjected to physical beneficiation involving washing, sieving, and magnetic separation, followed by chemical beneficiation using hydrochloric, sulfuric, nitric, and oxalic acids. Chemical composition was determined using X-ray fluorescence (XRF), while mineralogical analysis was conducted using X-ray diffraction (XRD). Particle size distribution and morphological characteristics were evaluated using optical microscopy and ImageJ software. The results indicated that raw silica sand contained up to 96.696% 𝑆𝑖𝑂₂ and 0.338% 𝐹𝑒₂𝑂₃. Beneficiation significantly enhanced silica purity and reduced impurity concentrations across all samples. The highest silica purity of 99.815% and the lowest 𝐹𝑒₂𝑂₃ content of 0.00976% were achieved after oxalic acid leaching. XRD results confirmed quartz as the dominant mineral phase in all samples, with the crystallinity index increasing from 57.5% in the raw sample to 90.3% after magnetic separation and remaining above 84% after acid leaching. Particle size analysis showed progressive reductions in particle area, perimeter, and Ferret diameter, indicating improved liberation and impurity removal. Morphological analysis revealed that particles remained predominantly sub-angular to moderately rounded throughout processing. The study concludes that Ugandan silica sand can be successfully upgraded through sequential beneficiation to produce high-purity silica suitable for high-quality solar glass production and with strong potential as a feedstock for metallurgical-grade silicon and photovoltaic applications. The final product (99.815% 𝑆𝑖𝑂₂) with extremely low 𝐹𝑒₂𝑂₃ (0.00976%) meets quality requirements for solar glass and has a promising potential as an upgraded feedstock precursor for carbothermic reduction to MG-Si, rather than direct semiconductor-grade silicon. Further studies should focus on pilot-scale processing and industrial application of the beneficiated silica.Item Investigating the energy potential of selected municipal solid waste in Mbale city.(Busitema University, 2026) Isabirye, IbrahimSolid waste management poses significant environmental and energy challenges for rapidly urbanising cities such as Mbale, Uganda. This study investigated the energy potential of three selected municipal solid waste fractions banana leaves, disposable diapers, and polythene bags in Mbale City, to identify their suitability for waste-to-energy (WtE) conversion pathways. Bomb-calorimetry-based proximate analysis showed net calorific values of 13.86 MJ/kg (equivalent to 3,851 kWh per tonne) for banana leaves, 18.50 MJ/kg (5,138 kWh per tonne) for disposable diapers, and 46.03 MJ/kg (12,785 kWh per tonne) for polythene bags, identifying polythene bags as the highest-value feedstock for thermochemical conversion. Laboratorybased biochemical methane potential (BMP) tests were conducted on boiled, alkali-pretreated banana leaves co-digested with cow dung at seven mixing ratios to evaluate biogas yield, methane content, and energy recovery. Physicochemical characterisation showed that banana leaves possess a high carbon-to-nitrogen (C:N) ratio that, when balanced through co-digestion with cow dung, improved methane yield. A 1:2 banana-leaf-to-cow-dung ratio produced the highest methane volume (330 mL from a 1,200 g digester charge, equivalent to a biochemical methane potential of 1.59 mL CH₄/g volatile solids), yielding a laboratory-scale energy recovery potential of 11.81 kJ — equivalent to approximately 12.2 kWh of recoverable methane energy, or 3.65 kWh of deliverable electricity at a 30% generator efficiency, per tonne of banana-leaf waste treated under the boiled and alkali-pretreated conditions used in this study. A multi-criteria Analytic Hierarchy Process (AHP) assessment further indicated that gasification is the most suitable technology for polythene bags, incineration for disposable diapers, and anaerobic digestion for banana leaves. Collectively, the three waste streams account for over 62% of Mbale City's municipal solid waste by mass, and a hybrid WtE strategy combining these technologies is estimated to yield a combined practical generation potential of approximately 4.17 MW for the city, overwhelmingly dominated by the thermochemical conversion of polythene bags and diapers. This research provides evidence-based guidance for sustainable municipal solid waste management and waste-to-energy technology selection in secondary Ugandan cities.Item Machine learning-based monitoring and performance analysis of a laboratory solar photovoltaic system using an internet of things framework.(Busitema University, 2026) Mbabali, FrankSolar photovoltaic (PV) systems are increasingly important for electricity generation in Uganda, but their performance varies with environmental and operational conditions, while existing monitoring provides limited integration of real-time sensing and advanced data analysis. This experimental study aimed to design and implement an Internet of Things (IoT)enabled monitoring framework integrated with machine learning for real-time monitoring and performance analysis of a laboratory PV system. Specifically, the study sought to: (i) design and implement an IoT system for real-time acquisition, transmission and monitoring of environmental and electrical parameters; (ii) develop and evaluate exploratory XGBoost and LSTM tasks for PV power prediction and time-series forecasting; and (iii) evaluate relationships between environmental conditions and directly measured electrical performance. The experimental platform comprised a 40 W PV module, ESP32 microcontroller, seven environmental and electrical sensors, Wi-Fi/MQTT communication and HiveMQ cloud storage. Data were acquired at approximately 5-second intervals across five monitoring sessions between May and August 2026, producing 1,729 valid observations, of which 1,001 were used for analysis. XGBoost was evaluated using a chronological cross-session holdout and linear-regression baseline, while LSTM was retained as an exploratory time-series prototype; graphical and statistical analyses were conducted. The IoT framework successfully acquired, transmitted, stored and visualized monitoring data. However, XGBoost did not generalize to an unseen session (R² = −0.571), while the linear baseline also performed poorly (R² = −0.109), indicating insufficient data diversity for deployable prediction. The irradiance channel was not calibrated, and the battery-buffered topology prevented validation of conventional instantaneous efficiency and performance-ratio measures. The study concludes that the IoT architecture provides a functional foundation for laboratory PV monitoring, but the machine-learning and performance indicators remain exploratory. Future work should recalibrate irradiance sensing, extend monitoring to multi-week or multi-season periods, log battery state of charge, and validate fault detection using labelled fault events before largerscale deployment.Item Development and evaluation of a vertical-axis wind turbine for generation of electricity : a case of Busitema hill.(Busitema University, 2026) Kukunda, AnyensiAccess to reliable and affordable electricity remains a challenge in many rural and peri-urban communities in Uganda despite the country's growing energy demand and abundant renewable energy resources. Wind energy offers a clean and sustainable solution for decentralized electricity generation, particularly where grid extension is economically unfeasible. However, the development of locally designed small-scale wind turbines suitable for Uganda's low- to moderate-wind conditions remains limited. This study aimed to develop and evaluate a Vertical Axis Wind Turbine (VAWT) for electricity generation using Busitema Hill as a case study. The study was conducted in three phases. First, the wind resource potential was assessed at Busitema University Main Campus (1,133 m asl), Busitema University Hill Top (1,188 m asl), and Busitema University Lower Plains (1,126 m asl) during the dry and wet seasons using a GT8709 BENETECH digital anemometer and a Global Positioning System (GPS). Second, a three-bladed twisted aero foil VAWT was designed using SolidWorks 2022 and analyzed through Computational Fluid Dynamics (CFD) in ANSYS Mechanical based on the measured wind characteristics. Finally, the prototype was fabricated and experimentally evaluated under field conditions. The assessment revealed significant spatial and seasonal variations in wind characteristics, with Busitema University Hill Top recording the highest and most consistent wind speeds (2.5–8.0 m/s) and a maximum wind power density of 52.4 W/m², making it the most suitable site for wind energy generation. The developed VAWT had a rotor diameter of 0.50 m, rotor height of 1.09 m, and swept area of 0.545 m². CFD simulation predicted mechanical power increasing from 9.4 W to 53.1 W and the power coefficient (Cp) from 0.215 to 0.282. Experimental evaluation showed rotor speed increasing from 241 RPM to 527 RPM as wind speed increased from 2.1 m/s to 4.6 m/s. Voltage and electrical power output also increased with wind speed, with the prototype producing a maximum electrical power output of 12.59 W, demonstrating its capability for small-scale electricity generation. The study concludes that Busitema Hill has adequate wind resources for small-scale electricity generation and that the developed VAWT is technically feasible for decentralized power supply under low- to moderate-wind conditions. Further optimization of the blade geometry, generator system, energy storage integration, and long-term field evaluation is recommended to improve performance and support wider deployment in similar environments.Item Optimizing operational efficiency and measurement integrity in Uganda’s fuel tanker logistics.(Busitema University, 2026-09) Nsimbe, JohnThis study develops a data-driven, mixed-methods decision-support framework that integrates operational variables with metrological variables, statistical analysis, qualitative coding (NVivo 15) and a Genetic Algorithm (GA) implemented in Python 3.12 and developed in VS Code. Field data (dispatch & delivery volumes, temperatures, densities, seal status, delays, telemetry uptime, safety scores, and stakeholder feedback) was collected from 106 trucks from Busia OSBP, Kampala depots, and fuel stations. All volumes were corrected to a 20 °C reference using fuel-specific thermal expansivity and density adjustments. Results indicated average fuel loss in the range of (1%–5%), with site patterns showing Busia OSBP (average absolute loss approx. 802.1 L), Kampala depots (approx. 500 L), and fuel stations (approx. 112.3 L). NVivo 15 coding corroborated qualitative priorities where Fraud & Siphoning Risks and Calibration & Measurement Integrity were the most frequently coded themes across depot managers, drivers, OMC staff, and end customers. Statistical analysis produced compressed component scores which were used as objective weights in the GA fitness function that balanced operational efficiency and measurement integrity. The GA converged on an optimized loss mitigation package termed as best solutions where PCA-derived component scores (FAC1 = - 2.16074, FAC = 2.000, FAC 3 = 0.96198) were used as objective weights in the fitness function balancing efficiency and integrity giving a best Loss = 43.0476 L and Best Fitness = 0.20897. These prioritized calibration scheduling for high-risk tankers and custody transfer points, automated volume correction factors and telemetry reconciliation at handovers and tamper-evident digital seals integrated with telemetry reconciliation rules. This combined strategy was selected because it simultaneously reduces meter drift exposure, enforces corrected volumetric accounting, and closes primary siphoning pathways. Scenario simulations and sensitivity tests show consistent improvements in delivery accuracy and reductions in expected loss compared with baseline heuristics. The final deliverable is a reproducible Python module and a ranked set of implementable interventions that together improve measurement integrity, reduce fuel losses, and strengthen regulatory confidence in Uganda’s downstream fuel tanker logisticsItem Antimicrobial hand wipes from banana fibres.(Busitema University, 2023) Kanene, Levi BrianAt the onset of the COVID-19 pandemic, one of the measures for combating the spread was the use of personal decontamination. Whereas sanitizing wipes are among the strategies for combatting COVID-19, there are growing concerns regarding their disposal, due to majority of them being made of non-biodegradable fibres. Additionally, some of the sanitizing solutions used have been found irritant, while some are carcinogenic. In this study, banana fibre wipes, impregnated with an organic antimicrobial formulation were developed as a sustainable alternative to synthetic fibre wipes and synthetic antimicrobial formulations. Banana fibres were extracted from banana pseudostem sheaths and alkali-treated at varying sodium hydroxide concentrations of 5 g/l – 20 g/l, varying temperatures of 85 0C to 105 0C under different immersion times of 60 min to 180 min. Other factors that were varied include the fibre length (20 mm – 40 mm) and the concentration of hydrogen peroxide (5 % v/v – 20 % v/v). Functional group analysis of the alkalitreated samples was done using the Fourier transform infrared (FTIR) spectroscopy. It was observed that during alkali treatment, the banana fibres undergo a loss of lignin and hemicellulose. Hydro-distillation was used to extract essential oils from the sap of Pinus caribaea var. hondurensis as a specie cited to possess antimicrobial activity. Phytochemical screening indicated that P. caribaea sap contains flavonoids and alkaloids. Extracts from lemon essential oil and cedar oil were equally studied and compared with oil from P. caribaea sap for antimicrobial efficacy. Assessment of the agar plates revealed that the P. caribaea extract did not show inhibitory activity to Escherichia coli (wild), E. coli (ATCC 25922), Staphylococcus aureus (wild), S. aureus (ATCC 25923), Pseudomonas aeruginosa (wild) and P. aeruginosa (ATCC 27853). However, essential oils from cedar and lemon showed inhibitory activity. From the Gas chromatography–mass spectrometry (GC-MS) analysis, oil obtained from P. caribaea sap was found to contain 23 bioactive compounds, with sabinene having the highest concentration of 34.24 % followed by βPinene (24.82%). A spunlaced non-woven fabric made from 100% banana fibres was impregnated with a commercial formulation containing essential oils from lemon, eucalyptus, cedar and orange. The antimicrobial efficacy test done on the impregnated wipe showed inhibitory activity against all the bacterial strains. Furthermore, the mechanical properties of the fabric showed that the tensile strength in the wet state increased by 4.29% and 20.414% in both the machine and cross directions respectively. Given that synthetic fibres are used in wipes to achieve a high wet tensile strength since most cellulosic fibres become weaker and disintegrate when wet, it can be concluded that banana fibres can be effectively used in wipes functionality given that they are biodegradable and are stronger when wet. From this study, there is need to carry out more studies on the dispersibility behaviour of the wet banana wipes and their rate of degradation during storage. Keywords: Sanitizing wipes, banana pseudostem, COVID-19, antimicrobial formulation, biodegradability, bio-based, nonwoven, plant extractItem CVD growth of ZrC layers at different temperatures.(SciEP, 2016) Alawad, BAB; Biira, S; Bissett, H; Nel, J; Hlatshwayo, TT; Crouse, PL; Malherbe, JBZirconium carbide (ZrC) layers were grown on a graphite substrate by chemical vapour deposition(CVD) at 1250°C, 1300°C and 1350°C. Zirconium tetrachloride (ZrCl4), methane (CH4), hydrogen (H2) and argon(Ar) were used as precursors. The deposited ZrC layers were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XDR showed ZrC characteristic peaks with free carbon. Free carbon incorporated in the ZrC layer increased with deposition temperature. The average of grain size also increased with deposition temperature. The latter findings were confirmed by SEM results. Keywords: chemical vapour deposition (CVD), ZrC, XRD, SEMItem Experts warn of Mass soil Pollution(2018-05-24) Tajuba, PaulUganda soils are getting polluted with chemicals which are depleting the soil fertility loosening bee population and killing other important micro-organisms the national environment management authority (NEMA) has warned.Item Kaberamoido hydrofoam machine left to rust(New Vision, 2018-04-10) Alomu, EmmanuelThe Hydrofoam machine donated to Kaberamaido district by the Office of the Prime Minister (OPM) has been lying idle for close to four years. Hydrofoam Machines were intended to help construct low-cost housing for vulnerable people and classrooms.Item How will Uganda's gas resource be used?(New Vision, 2018-04-10) Rwothungeyo, Billy32 sq km Kingfisher Oil field The associated gas that will be produced will bee used for powering a CPF and heating pipelines feeding the CPF with oil from well pads. The excess gas will be treated for LPG by recycling propane and the butanes.Item A crusader for sustainable energy(New Vision, 2018-04-04) Rwothungeyo, Billy"Hydrogen obtained from water will be the dominant fuel for most of our energy needs", Dr.Masa.Item Development of electronic waste management framework at college of engineering, design, art, and technology(Journal of Applied Material Science & Engineering Research, 2023) Nakeya, Zahara; Olupot, Peter; Wafula, Simon Peter; Kamulegeya, Obed; Nakimuli, Naqiyyah KimuliThe worldwide use of information and communications technology (ICT) equipment and other electronic equipment is growing. There is growing amount of equipment that becomes waste after its time in use. This growth is expected to accelerate since equipment lifetime decreases with time and growing consumption. As a result, e-waste is one of the fastest-growing waste streams globally. The United Nations University (UNU) calculates in its second Global E-waste Monitor 44.7 million metric tonnes (Mt) of e-waste were generated globally in 2016. The objective of the study was to develop a framework for improving e-waste management at the College of Engineering, Design, Art, and Technology (CEDAT). This was achieved by breaking it down into specific objectives, and these included the establishment of the policy and procedures being used in e-waste management at CEDAT, the determination of the effectiveness of the e-waste management practices at CEDAT, the establishment of the critical challenges constraining e-waste management at the College, development of a framework for e-waste management. The study population was 80 respondents, from which a sample of 69 respondents was selected using simple and purposive sampling techniques. This research was carried out to investigate the problem of e-waste and come up with a framework to improve e-waste management. The study reviewed the e-waste regulatory framework used at the college and then collected data, which was used to come up with a framework. The study also established that weak policy and regulatory framework, lack of proper infrastructure, improper disposal of e-waste and a general lack of awareness of the e-waste and the magnitude of the problem are the critical challenges of e-waste management. In order to appropriately address the issue, the policy and regulatory framework should be updated, localized, and strengthened. It will be helpful to launch awareness campaigns, issues. The study suggests a framework for e-waste improvement Keywords E-Waste, Treatment, Disposal, Computers, Model, Management Policy and Guidelines.Item Design review of an innovated single piston diesel engine in Uganda(Journal of Applied Material Science & Engineering Research, 2023) Wafula, Simon Peter; Kirabira, John Baptist; Mukasa, Norbert; Kamulegeya, Obed; Nakimuli, Naqiyyah KimuliEngineering designs are important in engine production. This research aimed at incorporating engineering principles and practices into the developed single piston diesel engine at Kevoton. Tests on the already innovated engine were carried out to evaluate the performance of the existing engines in terms of power, torque, rpm and exhaust temperature. Designs of the major components were generated together with material selection, which helped in determining whether the used material was appropriate for engine production. Results showed that the engine runs at a speed of 1800 rpm, a torque of 5 Nm, and a power of 10 HP with 2.4 liters per hour of fuel. The major components of the engine include the engine piston, the crankshaft, connecting rod, cylinder head and the camshaft. The power obtained after carrying out the new design was 13 HP, with a 5 Nm torque as well as 1 liter of fuel consumed per hour. It was realized that some components were not meeting the design specifications and the design was below the minimum required power of 13 HP. Power produced was less than 13 HP that was required to handle the purpose of engine manufacture, the engine was designed to be a prime mover to do most of the local. It was identified that the need of the engine should be considered as a primary requirement when coming up with the designs, the choice of injectors affect the amount of exhaust and engine testing requires consideration while designing an engine.