Centers for Ethio Mines Development

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Beneficiation and Characterization Techniques of Coal in the Western region of Tarcha Zuria Wereda, Southern Ethiopia
(Addis Ababa University, 2015-05) Daniel Kassaye; Zekarias Gebreyes (PhD)
Coal stands as the most plentiful and extensively found fossil fuel. Thanks to advanced methods, it can be extracted, moved, and stored efficiently and economically. The global trade of coal is experiencing consistent growth, accompanied by intense competition regarding supply and pricing. Nevertheless, the future commercial viability of coal hinges on its environmental sustainability, particularly on the ability of the power generation sector to minimize sulfur and other harmful emissions. This research examines the extraction methods employed at the Tarcha coal deposit located in Tercha Zuria Wereda, Southern Ethiopia. It utilizes a wet extraction technique to evaluate flotation responses and optimize key factors such as yield percentage and ash content. The primary goal of the study is to enhance the quality of coal by refining flotation processes and minimizing impurities. Laboratory experiments are conducted with varying particle sizes and different ratios of collector to frother in the froth flotation process. The results indicate that the highest coal recovery yields are achieved at a collector-to-frother ratio of 8:4, while also assessing how these variables affect ash content. The data reveal a clear trend of increasing ash content as particle size decreases, highlighting the importance of maintaining specific parameter ranges to optimize yield. Ultimately, this project offers valuable insights that could support local mining operations, particularly the ET-Mining Development Company, which is actively involved in job creation and community development initiatives. The outcomes of this study may also aid Ethiopia in meeting its domestic coal needs, potentially decreasing its dependence on imported coal as the nation advances its coal resource development
A Masters Project on Utilization and Quality Enhancement of Local Kaolin Clay Minerals Through Beneficiation
(Addis Ababa University, 2023-02) Abiyot Ayalew; Anteneh Marlign (PhD); Meseret Aregahegn:-Co-Advisor
Recently, some researchers labeled industrial minerals as ‘Development Minerals ‘because of their crucial role for fast local economic development and their necessity in the industrialization. The commercial term “Kaolin “is one of the most versatile industrial clay minerals composed essentially of kaolinite (Al2O3.2SiO22H2O). Kaolin What we call it as “China clay” have been found in Ethiopia as huge reserve estimated (20 million tons), throughout in the different parts of country. However, manufacturing industries import commercially value-added Kaolin from foreign countries due to the low qualities of local kaolin which have major impurities. The impurities of Kaolin from literatures and from XRF characterization of Raw Kaolin (RK) are quartz, mica, feldspar, iron oxide and titanium oxide minerals. Here my interest was to improve the qualities of this local kaolin through physical, thermal and chemical beneficiation to substitute imported commercial Kaolin. The two principal objectives of kaolin refining were the removal of impurities and the production of the desired particle-size distributions. Possibly to meet some industrial requirements, the coloring impurities (mainly iron oxides and other small amounts of fuxing components) must be removed. Based on the XRF analysis, the raw kaolin ore from AlemTena, Ethiopia containing 64.135 wt% SiO2, 25.747 wt% Al2O3, 4.838 wt% Fe2O3, and 8.22 wt% loss of ignition (LOI). Then it was physically beneficiated, chemically leached, and thermally treated for possible industrial use, especially for ceramic applications. The leaching experiments were carried out using oxalic acid solutions as leaching reagents for the iron extraction and colour enhancement process. A substantial reduction of iron oxide (4.838 to 3.107 wt %) and silica (64.135 to 57.285 wt%) SiO2 on the other hand a substantial increment of alumina (25.747 to 33.662 wt%) Al2O3 from the raw kaolin was observed at operating conditions of 2.0 M oxalic acid, the temperature of 90 °C, and contact time of 120 min. From Chemically leached kaolin we observed a significant whiteness and brightness. In other way the thermally treated kaolin was observed an increment of iron oxide (4.838 to 6.605 wt %) and also it lost its crystalline structure and becomes an amorphous phase but still its alumina and silica contents improved. Generally, from my study I understood that, the physically beneficiated, chemically leached, and thermally treated kaolin raw material can used to fabricate low-cost kaolin-based ceramic products.
Reverse Flotation as a Method for Beneficiation of Sekota Iron Ore
(Addis Ababa University, 2023-06) Temesgen Demissie; Abubeker Yimam (PhD)
Upgrading low grade Sekota iron ore to reduce the unwanted minerals and improve the quality is necessary to address these issues, in order to produce an acceptable feed for a steel production facility. The primary aim was to use reverse flotation as a beneficiation method for Sekota iron ore, in order to get a last flotation that meets the desired specifications. This process was divided into three stages: crushing, grinding, and flotation. For each of these stages, such as grinding, dosage of collectors, flotation duration, and procedures were determined. In the laboratory, where the samples were obtained, the ore was ground in a size of -0.074mm, using 250 grams of ore, with varying amounts of anionic oleic acid as the collector, 5mg/ton of activator and 5mg/ton of depressant, and floated with 2.0 g/ton of ethanol frother. The slurry was maintained at 10.5 using NaOH throughout the process. Before conducting any optimization tests on the iron ore flotation process, a laboratory procedure was developed to carry out the reverse flotation of the iron ore. The results showed that following these parameters, the flotation process achieved a final concentrate with a grade of 39.16% iron and an iron recovery of 41.29%. In this study, with varying duration of flotation, the iron grade ranged from 40-45% with an iron recovery of approximately 42%.
Identification of Reservoir Rocks, Properties and Structural Mapping of the Abay Basin in Viewing of Petroleum Exploration
(Addis Ababa University, 2023-06) Seid Endrie; Ketsela Tadesse (PhD); Bisrat Kebede (PhD) (Co-Advisor)
The basins has unique geological characteristics and holds different types of sedimentary rocks, such as sandstones, shales, carbonates, and volcanic rocks. The Abay (Blue Nile) Basin is located in the northwestern part of the country and covers an area of over 63,000 square kilometers. The Abay Basins covers a sizable area of the country. It includes Were Ilu, Mechale, and Legehida, which have notable oil seep exhibits. The contribution of the Upper Sandstone reservoir rock data is gathered from prior researchers and written materials in order to develop a relevant relationship between the types of reservoir rocks and structural mapping of the study area. In order to undertake the experimental tests for this study, samples are gathered from the field and sent to laboratory centers. In the laboratory, the chemical composition, porosity and permeability values of the reservoir rocks are determined using a representative sample that was collected from the study area. Based on the results of the experiments, the reservoir rock for the Abay (Blue Nile) Basin formation is an Upper Sandstone reservoir rock with relatively good porosity and excellent permeability. The Upper Sandstone rocks in the Abay basin have porosity values that range from 32.31 to 34.35% and permeability values that range from 1766 to 2350 mD, which suggests that the reservoir quality is generally very good (porosity)and excellent (permeability). During field work, it was discovered that the following fault systems were dominate in the study area. These includes; east-west (E-W) trending faults, northeast-southwest (NE-SW) trending faults, and northwest-southeast (NW-SE) trending faults. The oil and natural gas can be gathered and stored in reservoirs, the geological features called hydrocarbon traps. The presence of a petroleum system in the Abay Basin is strongly supported by the oil seepage at Were Ilu. The study area is characterized by rough structures, so airborne geophysical surveys are advised rather than ground geophysical surveys; seismic lines are needed for the study of the Abay Basin in order to delineate structural traps, stratigraphic traps, and indicate active faulting in the areas where it is possible for seismic line surveys; the basin requires further study regarding the main hydrocarbon fluids reservoir rocks, the total organic carbon contents of the source rocks and the carbonate reservoir rocks.
Reverse Flotation Potential of Bikilal Iron Ore Deposit: A Project Work on Wollega Area Western Ethiopia
(Addis Ababa University, 2023-06) Samuel Getaneh; Mulugeta Sisay (PhD); Guta Legesse (PhD) (Co-Advisor)
Iron is one of the most abundant rock forming elements, constituting about 5% of the earth’s crust. It is the fourth most abundant element next to oxygen, silicon and aluminum and after aluminum, the most abundant and widely distributed metal. Iron is extracted primarily from iron ores. The iron ores mainly include oxides and hydroxides such as magnetite (Fe3O4), hematite [Fe2O3], goethite [FeO(OH)], and limonite [FeO(OH)_nH2O].The primary gangue mineral in iron ores is quartz. The main problem regarding to beneficiate the Bikilal iron ore deposit are the presence of some deleterious gangue minerals such as Phosphorous, Alumina and silica and lack of advanced separation equipment. The aim of this project work is to indicate that the Bikilal iron ore deposit has naturally low grade iron content which is 41.2%Fe and it can be improved by anionic reverse flotation. The method used to upgrade this ore is first the qualitative and quantitative mineralogical analysis has been determined by atomic absorption spectroscopy (AAS) to know the initial amount of iron in the ore. Based on this information reverse anionic flotation has conducted in a batch flotation cell in two size classes at 75μm and 63μm. Oleic acid has been used as a collector whereas Ethanol used as a Frother. Modifiers such as activators, depressants and pH regulators have also used to promote the efficiency of flotation process. The concentrate of flotation has been analyzed again by (AAS) to evaluate the performance of the selected method. The amount from the concentrate has significantly increased from 41.2%Fe average grade to 62%Fe grade. The recovery of iron have been calculated as 65% for under 63μm and 74.4% for under 75μm.The amount of the concentrate for 63μm was 215g and that of 75μm was 250g. Therefore the recovery of iron from 215g under 63 μm is 65.5%Fe which is better than the recovery from 250g under 75μm that is 74.4%Fe. This project work mainly conducted based on (AAS) analysis results but it is not suffifeint to judge the general mineralogical composition and beneficiation process that should be applied in the Bikilal iron ore deposit. Therefore additional investigations and laboratory analysis such as (XRD), (SEM) and (XRF) are recommended to come up with a more tangible and realistic data. This paper have also discusses in detail about the factors that can affect the flotation performance of the ore and the alternative chemical reagents that can go through the mineralogy of Bikilal iron ore deposit.
Determining The Liberation Size of Mekaneselam Iron Ore Southern Wollo Zone, Northern Ethiopia: Implication for Beneficiation
(Addis Ababa University, 2023-06) Getahun Meseret; Dejene Hailemariam. (PhD); Belayneh Digafe (Mr.) (Co -Advisor)
Iron is one of the most important types of ferrous metals that extracted from ore minerals of iron, like magnetite, hematite and others. Ethiopia has a lot of iron ore resources which are located in different parts of the country. Among this, Mekane Selam iron mineralization, which is located in south Wollo zone, Northern Ethiopia, is the target area of this project work. The main objective of this project work was to determine the liberation size of the target iron-bearing ore mineral through mineralogical identification, chemical composition analysis, and examination of the particle size distribution. Atomic absorption spectrometry (AAS), X-ray florescence (X-RF), X-ray diffraction (X-RD) analysis, and sieve analysis, were widely used methods for this project work. The chemical composition of Mekaneselam iron ore consists of 16.55–77.59 % Fe2O3, 7.31–59.02% SiO2, and 1.44–17.38% Al2O3. With an average weight percentage of 48.34%,48.96% of Fe2O3, 34.7%,31.8 % of SiO2, 8.2%,10.68% of Al2O3, and 0.018% , 0.19 % of P2O5 and other minor compositions that resulted from X-RF and AAS compositional analysis respectively. The mineralogical results generated from X-ray diffraction showed that Mekaneselam iron ore consists of major iron-bearing ore minerals of 40–60% hematite, 8–59% goethite, with an average value of 49.13% hematite and 27.85% goethite. The dominant associated gangue minerals are 1–21% quartz with an average value of 11.5% and 1–23.5% kaolinite with a mean value of 8.6%. The examination of the particle size distribution of sizing curves shows that 80 percent passing (P80) of the grinded ore sample is 1100μm. The size-wise chemical compositional analysis of AAS revealed that a higher weight percentage of the target ore mineral was recorded under a sieve size range of (-250μm + 180 μm). This implies that the appropriate liberation size of the target iron-bearing ore mineral is found between (-250μm and +180μm) sieve size ranges. This liberation size range shows a cumulative passing of 38% total particles. The chemical and mineralogical results of Mekaneselam iron ore indicate that the ore is very low grade and can be upgraded to commercial values by using gravity concentration followed by a high-intensity magnetic separator. In addition, it can be upgraded by magnetic reduction roasting (MRR), followed by a low-intensity magnetic separator.
Characterization of Ore and Gangue Mineralogy at The Ashashire Gold Deposit, Benishangul- Gumz Region, Western Ethiopia
(Addis Ababa University, 2023-06) Getnet Belachew; Melesse Alemayehu (PhD); Basalifew Zenebe (Mr.) (Co-Advisor)
Gold is a precious metal that is highly prized and has been significant throughout human history. It has been used as money and for ornamental purposes. It is a crucial component in electronics, medical equipment, and other industrial uses. Around the world, mining operations have sprung up in response to the demand for gold, and efficient extraction and processing depend on an understanding of the mineralogy of gold deposits. This study aimed to characterize the mineralogy of the Ashashire gold deposit located in the Benishangul Gumuz Regional State, Western Ethiopia. Six representative mineralized core samples were analyzed using fire assay with atomic absorption spectroscopy (AAS), inductively coupled plasma (ICP), quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN) and X-ray diffraction (XRD). The study found that the gold in the deposit occurs primarily as native gold and gold-telluride, with a strong association with tellurium and often found as free particles or in association with gangue minerals such as quartz and pyrite. Pyrite is the dominant sulfide mineral detected in all core samples, with only trace amounts of chalcopyrite detected. The gangue minerals present in the deposit are mainly quartz, ankerite-dolomite, muscovite, chlorite, and albite, with lower levels of paragonite, rutile, magnetite, and calcite. The presence of tellurium suggests that specialized processing techniques may be required to liberate the gold from the tellurides. The degree of liberation, liberation sizes, and recovery of gold are all impacted by the texture of the ore. The gangue mineral composition of the ore can also impact gold processing in several ways, including cyanide consumption, clay coating and gold adsorption, ore hardness, mineralogical complexity, and processing costs. The mineralogical data can be used to develop a suitable processing route, taking into account the ore texture, gold mineralogy, and gangue mineral composition. A combination of techniques such as gravity separation, flotation, cyanide leaching, pressure oxidation, and CIL/CIP could be employed to maximize gold recovery and minimize environmental impact. Further metallurgical testing and optimization are necessary to fully understand and optimize gold recovery from this deposit.
Comminution circuit flow sheet Development for Optimum Performance of Iron Ore Processing, in the Case of Sekota, Wagehimra, Northern Ethiopia
(Addis Ababa University, 2023-06) Ephrem Tialhun; Abubeker Yimam (PhD); Megeressa Bedo (Mr.) (Co-Advisor)
Sekota Iron Ore aims to contribute to the economic development of Ethiopia by exploiting and producing high-quality iron ore for both domestic and international markets. The company expects to create employment opportunities and generate revenue for the government, which can be used to invest in other developmental projects. Besides, the establishment of Sekota Iron Ore could also help to reduce the country's reliance on imported iron and steel products, promote local industries and contribute to the growth of the mining sector. Most of the minerals extracted in the nature are founded disseminated with the gangue, this creates a necessity to liberate these particles and reduce the size for principally reach a big concentration of the desired material. As the comminution is by far the largest energy consumer in most mine sites, the study of the mineral processing try to conduct this size reduction with the bigger efficiency possible. comminution flowsheet design is a critical process in the production of iron ore. In this study, the flow rate was fixed at 150t/h with the Crusher specification of a Cedarapids JC24x36 jaw crusher model and a Nordberg Hp 300 S/M cone crusher. Based on the mineralogical information and ore properties provided the AggFlow Version 460.22 software is used to conduct, a comprehensive comminution flowsheet design to achieve the desired particle size distribution and mineral liberation. In the communition of primary crusher stage Iron ore at top size of 42 inches or (1066.8mm) generates 5 different ranges of materials, the first is at a size of 45mm, the second at 10mm, and the third is at 8mm, between 15 and 8mm and between 23.5 and 15mm. The primary crusher, a Cedarapids JC2436 Model Jaw crusher, was required to reduce the feed size with closed side setting of 69.85 mm to a manageable size of end product 21Mtph for further processing. The Nordberg Hp 300 S/M cone crusher was used as a secondary crusher with closed side setting (CSS) of 28mm to further reduce the particle size to 26Mtph. To complete the task several choices analyzed and as final design used 1 jaw crusher Cedarapids Jc 2436, and two cone crushers Nordberg HP 300 S/M. some screening and conveyors placed in the design to increase the reduction ratio of the equipment.
Determination Of Work Index of Spodumene from Kenticha Ore, Southern Ethiopia
(Addis Ababa University, 2023-06) Anuwar Mama; Bisrat Kebede (PhD)
From Kenticha, Southern Ethiopia, granite and kenticha spodumene ore were collected and used separately as reference ores. Each test ore was weighed at 2000 grams, and the reference ore was weighed at 500 grams, and all were ground in a lab ball mill under the same conditions. Size analysis of the feed to the ball mill and the output from the ball mill was performed on both the test ore and the reference ore, with the results properly tabulated. The feed and discharge particle sizes for the samples going into the ball mill were calculated using the Gaudian Schumann formula to ensure an 80% passing rate. The work index of the Kenticha spodumene ore was then calculated using Bond's equation, and it was discovered to be 11.391 kWh/t.
Grindibility and breakage characteristics of Sekota iron ore deposit in Wag-Himra Zone, Northern Ethiopia
(Addis Ababa University, 2023-06) Yohanes Belachew; Bogale Tadesse (PhD); Birtukan Yenealem (Co-Advisor)
In this study, the influence of mill rotation speed and grinding time were investigated on Sekota iron ore grinding process in a batch mill with length 150 mm and inner diameter 150 mm. The particle size distribution of the feed was carried out by an electric sieve and the bulk feed was classified into three samples to perform the grinding test. Three distinct iron ore feed size fractions between -335mm to +0.71mm, -0.71mm to +0.15mm and -3.35 to -0.075mm separated by a series of √2 gaps were prepared. The fractions were milled at different grinding times (5, 15, 25, 35, 45 and 60 min) at 450 rpm and at different mill rotational speeds (250, 300, 350, 450 and 550 rpm) at 25 min. The mill rotation speed and grinding time affect the energy consumption, the desired grind size and the P80 of the feed size fraction. When grinding time increased from 5 to 60 min, the percentage of cumulative mass of target size increased from 8.5 to 31.1%, from 7.1 to 22.8% and from 10.6 to 26% for coarse, fine and mixed iron ore size fractions, respectively. Likewise, a significant amount of the desired grind size is produced as the grinding speed increases until the maximum critical speed is reached. For all feed size fractions, the required grind size amount (-0.075 mm) is not achieved at grinding times from 5 min to 60 min and at maximum mill rotation speed (450 rpm). The product size distribution of the three iron ore feed size fractions were also affected as the grinding time and the mill rotation speed increased from 5 to 60 min and 250 rpm to the maximum speed (450 rpm). The P80 values of all feed size fraction generally decreased both milling time and mill speed are increased from 5 to 60min and 250 to 450 rpm respectively. Unlike the P80, the energy consumption of the ball mill increases significantly as the mill speed and grinding time increase from 250 to 450 rpm and from 5 to 60 minutes respectively.
Characterizing the Ore Mineralogy of Kenticha Pegmatite for Lithium Beneficiation, Southern Ethiopia
(Addis Ababa University, 2023-06) Gutema Mekonen; Alberto Velazquez (Prof.); Kaleb Gebreyes (Mr.) (Co-Advisor)
Lithium is a highly sought-after resource crucial for rechargeable batteries, and the Kenticha pegmatite ore deposit in Ethiopia holds potential as a source of this valuable element. The focus of this study was to investigate the mineralization of Kenticha, specifically the spodumene ore, and its suitability for beneficiation processes. Through XRD, AAS, and petrographic microscope analysis, the study identified the minerals present in the spodumene pegmatite ore, their average composition, and mineral texture for spodumene concentrate liberation. Spodumene was found to be the most abundant mineral, but its low degree of liberation from other minerals required additional processing steps for high yield. Weathering significantly impacted mineral identification and quantification, affecting diverse mineral morphology and liberation. The study's findings have implications for mining operations, exploration, and processing strategies, suggesting additional processing steps for spodumene recovery and highlighting the impact of weathering on mineral characterization. The study provides valuable information on mineral texture and liberation for selecting processing methods for beneficiation, contributing to a better understanding of the Kenticha pegmatite ore deposit's mineralization potential for lithium extraction.
Study on Flotation Response of Coal from Gamo Zone Southern Ethiopia
(Addis Ababa University, 2023-06) Kibru Woldemariam; Abubeker YImam (PhD)
Based on the log results of pits, geophysical results and areal coverage of coal deposits in Gamo zone, Kuccha woreda, it is roughly estimated to have 744,174.96 tons of coal. The flotation response of a coal is a critical factor in determining the efficiency of coal beneficiation processes. The study investigated the effects of collector dosage, frother dosage, and particle size on the flotation response of Gamo area coal in a 3-liter batch flotation experiment. Kerosene was used as the collector and n-octanol as the frother. Full factorial Design was applied to investigate the effect of collector dosage (10ml, 20ml), frother dosage (2ml, 6ml) and particle size (-250 μm +125μm -125 μm) on the process of flotation using Design expert® 6 software, which shows the significant influence on the value of yield and recovery. The result showed that the optimum condition for the process was 18.3ml, 4.7ml and -125 μm which resulted in 81.7% yield,90% combustible matter recovery and 37.5% flotation efficiency index. The findings suggest that careful optimization of reagent dosages and particle size can significantly improve the flotation response of Gamo area coals, with potential applications in coal beneficiation processes.
Mineralogical Assessment of Ashashire Gold Ore to Investigate Its Beneficiation Potential by Flotation Method, In Benshangul Gumuz Western Ethiopia
(Addis Ababa University, 2023-06) Kiross Haile; Bogale Tadesse (PhD); Kaleb Gebreyes (Mr.) (Co-advisor)
Primary and placer gold deposits are found in the Ashashire area, which is an orogenic gold prospect area. These resources are a source of income for both companies and artisanal gold miners. It is located in the Western Greenstone belt of the Precambrian volcano-sedimentary belt, at Kurmuk Woreda, in the western Ethiopian region of Benshangul Gumuz. The region is near to the Sudanese border and is referred to as Ashashire informally. Gold is the most valuable commodity in the world. Due to the significant study that experts from all around the world have done on the history of gold, namely its birth. Ethiopia is a developing country, but it has not yet reached its full potential. Some claims and exploratory activities claim that Ethiopia is rich in precious metals, including gold, which are processed using incredibly archaic methods in many different regions of the country. As a result, the main objective of this research project is to investigate the mineral makeup of Ashashire gold ore in order to assess its potential for flotation-based beneficiation. The geochemistry was validated by both inductively coupled plasma mass spectrometry and fire assay. The petrographic analysis includes a description of the host rock and ore deposit. The host rock mostly consists of chlorite, carbonate, sericite, and quartz, with minor amounts of greenschist to amphibolite facies metamorphic minerals. Pyrite, pyrrhotite, magnetite, sphalerite, chalcopyrite, galena, and gold are found in the ore after petrographic investigation. According to ore microscopic and geochemical study, gold mineralization has strong spatial connections with alteration traits as carbonitization, silicification, sulfidation, and sercitization. The concentration of gold increases with host rocks that have been sericitized, carbonitized, silicified, and sulfurized. According to the ore geochemical data, the gold deposit contains up to 10.3ppm and is contained in chlorite-sericite-carbonate schist in carbonate-quartz veins. This gold deposit's target region is the Ashashire region. It is possible that gold is precipitated from hydrothermal solutions due to the intense wall rock alteration and the strong relationship between carbonate-quartz veins and gold. Every experimental mineralogical examination conducted by organizations and individuals in Ashashire ore mineralogy produces comparable results. It is not economically feasible to concentrate Ashashire gold for the reported gangue minerals using the flotation method. Due to the possibility of large recovery losses and increased chemical reagent consumption from such gangues. Then, prospective approaches for recovering gold from the Ashashire gold deposit include combining processing technologies like gravity separation, flotation processes, and leaching.
Characterization of Coal Composition of Shela Area, Wolayita Zone, Southern Ethiopia, Implication
(Addis Ababa University, 2023-06) Abinet Markos; Sofiya Abdulkadir (PhD)
The present study focused on the mineral characterization of Kindo-Didaye coal by adiabatic Calorie Metter, Gravimetric, hard groove index and proximate techniques. The result showed that coal quality ranged between (2475.79-10931.96Btu/lb); Sulphur (<0.02 % to 2.93%), moisture (1.21 to 1.99 %), volatile matter (15.45 to 26.37%), ash content (28.19 to 71.26%) and fixed carbon (11.21 to 44.23%). The majority of the Coal samples fall within lignite “B”, subbituminous “B” and sub-bituminous “C” ranks and none agglomerating. The grindablity index of the majority of the coal samples has the range (56.2-66), which HGI values of the Shela area coal samples indicate that most of the samples can be characterized as lignite and are also extremely challenging to grind.
Evaluation of the Nature of Porosity in Carbonate Rock Of Hamanlei Formation, Ogaden Basin, Ethiopia: Implications For Prediction of Reservoir Quality
(Addis Ababa University, 2023-06) Yimam Ali; Solomon Kassa (PhD)
The Ogaden basin is the largest sedimentary basin in Ethiopia having 350,000 km2 areal coverage. It is also the most studied sedimentary basin in Ethiopia. Nonetheless, the amount of data gathered from this baisn is not enough to better comprehend the petroleum system of the basin. The Hamanlei carbonate rock in the basin makes good reservoir rock. The nature of this reservoir rock is complex owing to various factors. Despite detail studies were conducted to understand the reservoir property, particularly core and wireline log study, further studies are needed for better characterization of this reservoir rock. To further characterize the reservoir property, i.e. porosity, of this rock and prediction for reservoir quality, petrographic and image analysis were performed. The outcome of this study provides valuable insights into the mineralogy and texture of the studied rocks. Furthermore, it highlights the importance of understanding the different pore types that enables to better interpret the reservoir quality and potential flow characteristics of the studied rocks. Generally, the porosity value of the reservoir rock is too small which is caused by the dominant proportion of matrix and cement
Value Addition of Ethiopian Gemstones
(2023-06) Mehatebe Gebrewold; Abubeker Yimam (PhD); Aselefech Mitiku (Ms.) (Co-Advisor)
Ethiopia is well recognized for producing gemstones. Numerous high quality gemstone varieties, such as opals, emeralds, sapphires, amazonite, amber, rubies, tourmalines, aquamarines, chrysoprase, peridot, chalcedony, obsidian, agate (scapolite agate), jasper, petrified wood, and various types of quartz, including precious quartz, are the main gemstones mined in the nation. However, the industry continued to generate little appreciable economic advantage because the country mostly exported rough gemstones with no added value. This project study intends to demonstrate the technology needed for adding value to various Ethiopian gemstones and the associated financial advantage. The following measures were taken in order to add value: Sorting the chosen gemstone by specie, selecting clean, color-full, large (excellent size to cut) pieces from the rough collection, cutting, polishing, and ultimately faceting of the chosen gemstone. The value added gemstones are then each given a physical description based on their Color, Clarity, and Cut. Finally, a price estimate has been generated for the gemstones with enhanced value. The project's findings showed that enhancing the value of the rough gemstone might produce earnings of up to 1,610,590 ETB/Kg of Opal, 293,560 ETB/Kg of Crystal Quartz, 213,040 ETB/Kg of Green Obsidian, 48,565 ETB/Kg of Jasper, 43,730 ETB/Kg of Agate and 43,675 ETB/Kg of Black Obsidian. As a result, small-scale gemstone business owners can profit from the high prices of their products and the country can increase the foreign currency revenues from selling the value-added gemstones by adding value to the rough gemstones through the use of relevant technology.
The Beneficiation of Lithium from A Brine Solution of Afdera Lake Using Evaporation and Chemical Treatment Method, Afar, North Eastern Ethiopia
(Addis Ababa University, 2023-06) Elias Mamushet; Bogale Tadesse (PhD); Abayinesh Mitku (Mr.) Co-Advisor
Lithium is a crucial metal with a rapidly growing market demand, mostly due to its use in lithium-ion batteries for electric cars and medical devices. Lithium resources connected to pegmatites and rift-bound brine deposits may exist in Ethiopia. The current project work, the beneficiation of lithium was conducted on Afdera brine lake Afar, North Eastern Ethiopia. This project aims beneficiating lithium using Evaporation and chemical treatment method. Totally 20 litter sample were collected from the lake using Purposive and random sampling method in order to analyzed in the laboratory for Atomic Absorption Spectroscopy (AAS) for the Lithium and major cation as well as for beneficiating lithium metal from the brine solution. The AAS result of the Lithium contents in brine water of Afdera lake is 8.7ppm which is relatively higher than other lakes in the main Ethiopian rift. The concentration of Sodium and potassium is extremely higher in the lake which is 82946 ppm and 661.5 ppm respectively while lithium is much lower. Even if the Lithium concentrations is below the cut of grade 200ppm it was processed using evaporation and chemical treatment method and the content of the lithium reached 53.8% in the concentrate. Despite the lake's lithium concentrations being below what can be commercially extracted, it can still be processed as a byproduct during the manufacturing of potash using sun evaporation pans. The current study strongly suggests that additional research is needed merely to assess the lithium resources as a primary product and as a secondary byproduct during the potash mining process in Afdera Lake and the surrounding area.
Application of Montmorillonite Type Bentonite Clay From Chacha Area as Alternative for Local Construction Material
(Addis Ababa University, 2023-06) Addisu Misgana; Abubeker Yimam (PhD); Enatfanta Melaku (Mr.)
Hollow concrete block are produced from derbanPozolana Portland Cement (PPC), pumice and other aggregates (sand, scoria, gravel and clay). Mixing ratio and composition for HCBs although depend on the availability of materials. It is widely varying among the producers of cottage and industrial scale. However, all producers apply cement as a major constituent for binding. The demand of cement for HCBs and other construction materials is very high while the cement supply is very low. As a result, cost of production and sell price in the market is expensive and becoming not affordable for end users. The objective of this study is to investigate and evaluate the effect in using relatively cheaper bentoniteas cement replacement in HCBs production. Bentonite is available in a bulk when compared to cement. In the process focushas been given for curing and compressive strengthof HCB by varying the amount of cement and bentonite as major constituents in three ways (10kg bentonite replacing 10kg cement, 15 kg bentonite replacing 15 kg cement and 20 kg bentonite replacing 20 kg cement for a single batch /64 HCBs). All HCB samples were produced using 0.84 m3 pumice, 40 liters’ water. In addition silicate analysis (chemical composition) and physical properties (bulk density, moisture content and free swell test) of Chacha clay. Standard Compressive strength tests using (CES24:2013) method for HCBs of six sample replicates with average result on a total of 54 samples tests were made for 14, 21 and 28 age of curing time. For 28days’ age the average compressive strength (N/mm2) of 1.43, 1.27 and 1.23 were achieved by 10%, 15% and 20% bentonite replacement respectively. The compressive strength of HCBs is found to increase with increase of curing age and decreases with increase of the bentonite loading ratio. Generally, replacing of cement with bentonite at 28 days, a 10% bentonite replacement obtained the highest strength value, followed by a 15% bentonite loading ratio and a 20% bentonite loading ratio.
Identifying the Effects of Diagenesis on Reservoir Quality, Adigrat Sandstone, Ogaden Basin, South East Ethiopia
(Addis Ababa University, 2023-06) Gemeda Ayansa; Solomon Kassa (PhD)
The Ogaden basin is a vast sedimentary basin having 350,000 km2 areal coverage. Although it is the most studied region in Ethiopia, so far 72 wells have been drilled in the area, i.e. the number of wells per area coverage is 4861 km2. Due to large area coverage of Adigrat Sandstone reservoirs there, the Ogaden Basin in SE Ethiopia is of great importance for hydrocarbon exploration and development. However, diagenetic processes, which modify the rock's physical properties, affect its ability to store and flow hydrocarbons, and can have a significant impact on reservoir quality. Despite its significance as a reservoir, it is practically impossible to predict how diagenesis may affect the sandstones' reservoir quality. This study was conducted to find out the types of digenesis and its effect on the quality of Adigrat sandstone reservoir. To this end, 15 (fifteen) thin sections of Adigrat sandstones from YH-4 well were prepared and, ImageJ, JMicroVision, and petrographic analyses were employed to characterize the reservoir's diagenetic effect. The cementation of authigenic clay, silica, growth of authigenic glauconite, mineral dissolution, and load compaction are the key diagenetic processes that have impacted the reservoir quality of Adigrat sandstones. According to the framework grain-cement interactions, Clay cements, particularly illite, that partially line and fill pore spaces, developed alongside or after the early calcite cement's precipitation. Thus, it is inevitable that the reservoir rock’s porosity and permeability will decrease by this clay, which acts as a pore-choking cement.
Reservoir Characterization of Adigrat Sandstone Around Calub Ogaden Basin, Ethiopia
(Addis Ababa University, 2023-06) Alemu Jifar; Samuel Getenet (PhD)
The sedimentary Basins of Ethiopia cover a significant portion of the country and there are five distinct sedimentary basins. Ogaden Basin is located in the southeastern part of the country and covers an area of about 350,000 sq. km. The Reservoir characterization of Adigrat sandstone of Calub Ogaden Basin Ethiopia using seismic and well-log data is the focus of this work. The data used for the study consisted of seismic lines, well logs, and published reports to achieve the aim and objectives of the work. Data from wells Calub-1, Calub-2, Calub-3, and Calub-4 were deployed. Software including Petrel, Eclipse, Interactive Petrophysics, and ArcGIS was used. A petrophysical analysis was carried out to determine porosity, permeability, water saturation, and other reservoir parameters. The methods used for analysis involved petrophysical analysis, geostatistical analysis, and reservoir modeling. The Calub wells had relatively consistent porosity and permeability slightly lower values. Based on these results, further exploration and production activities are recommended, but additional data collection and analysis are necessary to fully characterize the reservoir properties and optimize production. This includes conducting well tests, seismic surveys, and reservoir modeling to better understand reservoir behavior and optimize production strategies.

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