Department of Mining Engineering
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Item Evaluating the effectiveness of tobacco-derived biochar for the adsorptive removal of cyanide from gold mine tailings case study : Greenstone resource and mining limited.(Busitema University, 2026-07) Achomo, PriscaCyanide-containing gold tailings pose significant environmental and public health risks due to the high toxicity of cyanide compounds released during gold extraction processes. This study evaluated the effectiveness of tobacco-derived biochar (TBC) for the adsorptive removal of cyanide from gold mine tailings at Greenstone Resource and Mining Limited. Tobacco biomass waste was converted into biochar through slow pyrolysis at approximately 700°C under oxygen-limited conditions and subsequently characterized using Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD). The characterization results revealed the presence of functional groups such as hydroxyl (–OH), carbonyl (C=O), and carboxyl (–COOH), as well as a porous and predominantly amorphous surface structure suitable for cyanide adsorption. Response Surface Methodology coupled with Central Composite Design (RSM-CCD) was employed to optimize the adsorption process by investigating the effects of adsorbent dosage, initial cyanide concentration, contact time, and pH on cyanide removal efficiency. Batch adsorption experiments were conducted using simulated cyanide solutions within concentration ranges of 65–325 mg/L. The optimum adsorption conditions obtained were an adsorbent dosage of 0.92 g/L, contact time of 148.79 minutes, and pH of 11.73, under which the model predicted a cyanide removal efficiency of 93.00%. Experimental validation using real gold tailings spiked to 65 mg/L cyanide concentration produced an average removal efficiency of 91.80% with an Absolute Percentage Error (APE) of 1.31%, indicating good agreement between the predicted and experimental results. Adsorption isotherm studies showed that the adsorption process followed both Langmuir and Freundlich models, while kinetic studies indicated that the pseudo-second-order model provided the best fit, suggesting that chemisorption was the dominant mechanism. The study demonstrated that tobacco-derived biochar is an effective, low-cost, and environmentally sustainable adsorbent for cyanide removal from gold tailings and offers a promising approach for waste valorization and environmental remediation in the mining industry.Item Application of Machine Learning to optimize Gold recovery during Cyanide Leaching at Wagagai gold mine(Busitema University, 2026) Ayebale, ReyesThe cyanide leach process, also known as gold cyanidation, is a hydrometallurgical technique used to extract gold from low-grade ore, yet its efficiency is often compromised by the complex, non-linear interactions among various operational parameters (e.g., cyanide concentration, pH, leaching time, pulp density, and dissolved oxygen). Traditional optimization methods heavily rely on subjective operator experience, leading to suboptimal and inconsistent gold recovery rates.This study addressed this challenge by applying machine learning techniques to predict and optimize gold recovery during cyanide leaching at Wagagai Mining (U) Limited. A dataset of 2801 historical plant records was developed using key process variables, including cyanide concentration, pH, leaching time, pulp density, and dissolved oxygen. Three models including Multiple Linear Regression (MLR), Random Forest (RF), and Artificial Neural Network (ANN) were developed and evaluated using statistical performance metrics including the coefficient of determination (R²), Root Mean Square Error (RMSE), and Mean Squared Error (MSE). The results showed that the ANN model outperformed the others, achieving the highest predictive accuracy with an R² of 0.9444 and RMSE of 1.0209, compared to RF (R² = 0.9133) and MLR (R² = 0.8509). Hyperparameter optimization further improved ANN performance and confirmed that a single hidden layer with 10 neurons was optimal. The optimized ANN predicted a maximum gold recovery of 96.42% at a cyanide concentration of 800 mg/L, pH of 10.67, leaching time of 48 hours, pulp density of 35%, and dissolved oxygen of 12 mg/L. Partial Dependence Plots (PDPs) and sensitivity analysis were used to interpret the model, revealing that pulp density and cyanide concentration are the most influential variables affecting recovery, while pH and dissolved oxygen play significant but moderate roles. Sensitivity analysis revealed that pulp density (10.53) and cyanide concentration (8.004) were the most influential variables. The findings demonstrate that ANN-based models are effective tools for optimizing cyanide leaching and improving operational efficiency in gold mining.Item Uganda evaluates test crude oil bidders.(New Vision, 2018-05-15) Vision, ReporterThe Government is yet to decide on who is to take Uganda's stockpiles of the test crude oil. The successful bidder was expected to be announced on April 27, but sources at the Uganda National Oil Company (UNOC) said they experienced some delays.Item There are few institutions handling oil courses- Opuda.(New Vision, 2017-09-06) Opuda, AsiboThe governor of Bank of Uganda, Emmanuel Tumusiime Mutebile, while launching the laboratories at the International University of East Africa note that: "Central to economic development is the application of progressively more advanced technologies in production processes like oil mining and infrastructural development."Item Phosphates mining in Tororo set to start(Daily Monitor, 2017-10-16) Kahungu, Thembo MisairiGuangzhou Dongsong Energy Group Limited, a Chinese company licensed to mine phosphates in Sukulu hills in Tororo District, is set to start full-scale activities, Daily Monitor has learnt.Item Gold mining fueling criminality- leaders.(Daily Monitor, 2017-09-27) Amanyisa, ZadockLeaders in Buhweju district have decried the rising cases of criminality following the booming gold mining business in the district. The leaders expressed their worry last week during the "voice projection inception workshop" organised by Global Rights Alert,Item Government calls for more oil explorers(New Vision, 2018-04-26) Odyek, JohnThe Government has called for more investors in the oil and gas sector to participate in the second competitive licensing set for next year.Item Regional oil players to discuss sector growth(New Vision, 2018-04-24) Odyek, JohnUganda' oil and gas sector is gaining momentum and more players are angling to reap from the activities. As a result, oil sector leaders have organised a convention intended to create dialogue with other players in the region.Item Establish regional oil depots, not one centre in Mpigi(Daily Monitor, 2017-10-10) Oketa, JamesNews is that the government is set to construct national refined oils storage facility in Mpigi district, which is a non-oil producing area, but a large fuel consumption centre. This is a good idea. The government that encourages the teaching of sciences yet it appears that it does not make use if the scientists in making critical decisions such as this one.Item Oil exploration across boundaries(New Vision, 2018-06-05) Sebikari, Gloria' Countries can opt for joint operatorship where the two countries identify one company to exploit the petroleum resources and they share the proceeds'Item Scotland wants to plug skills gap in oil sector(Daily Monitor, 2017-10-20) Kamukama, EroineSetup. For Uganda to monetise its oil and gas reserves, it has to put enabling infrastructure in place.Item Uganda's small miners to benefit from ACP-EU's sh43b soft loans(New Vision, 2017-07-10) Odyek, JohnUganda's miners are set to benefit from a $12m (about Sh43b) loan from the European Union (EU), to support those mining development materials. The loan targets small businesses that quarry, manufacture and trade in industrial minerals, such as gravel, clay, granite, gypsum and other local materials critical for development in five African countries.Item Reforms to attract investors in mining sector underway(Daily Monitor, 2017-10-12) Nakaweesi, DorothyIn a bid to attract new investments in Uganda's Mineral sector, government has embarked on major regulatory and legal reforms for sustainable development.Item Mukono leaders divided over illegal sand mining.(New Vision, 2017-08-09) Nsubuga, HenryThe Police and Mukono district council leaders have failed to stop illegal sand mining at Wansinga Village, which has encroahed on the Nsanja- Mpunge road. The council, on May 29, resolved to immediately stop sand mining in the area because the process was threatening the lives of road users,Item Govt suspends mining activities.(New Vision, 2017-08-16) Karugaba, MaryIn an effort to get rid of illegal miners, the government has suspended all mining activities in the country for three months. The state minister for energy, Eng. Simon D'ujanga, representing energy minister Eng. Irene Muloni, told MPs on the natural resource committee yesterdayItem Oil: Preparing locals for more land acquisition(New Vision, 2018-05-22) Atuhairwe, RobertThe discovery of oil avails Ugandans with many opportunities, including jobs, increased revenue, development and poverty alleviation, however thee industry is being delayed due to challenges regarding land on which major projects are to be set up.Item Oil refinery consortium in place: What next?(New Vision, 2018-05-15) Rwothungeyo, BillyWhile signing of an agreement to build an oil refinery last month might mean thee earliest the plant will go into production is 2021, other oil developments will not be impeded, officials said. The framework agreement signed at state house Entebbe involved the Albertine Graben Refinery Consortium - a partnership between Italy's Nuovo Pignone International owned by American multinational conglomerate General Electric and SAIPEM SPA and Mauritius' Yaatra Africa and Lion works Group Limited.Item Experts warn on negative impacts of oil pipeline(New Vision, 2017-08-02) Rwothungeyo, BillyAfter a period of somewhat slow activity, developments in the oil and gas industry are picking pace ahead of the 2020 production year. Works on key infrastructure such as the refinery, pipelines and storage facilities will have to be done before thee production date and with these developments come impacts.Item Confusion mars kilembe mines deal.(Daily Monitor, 2017-11-01) Musisi, FredericA government- appointed committee has recommended termination of a contract to Tibet Hima Mining for Company Limited (THMCOL) and called for a fresh search to secure a new investor to revive Kilembe MinesItem Government declares sand, muram minerals(New Vision, 2018-05-09) Mubiru, ApolloAnybody found extracting sand and murram without a license from the energy minister will be liable to one year imprisonment or a fine not exceeding sh500,000 or both. Incase of a company the fine is sh1m. This is after the cabinet approved the mining and mineral policy which widens the definition of minerals to include sand, granite, stones and murram.