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Slope stability of the Pit Number One, El Encino mine, southern Jalisco, MexicoHernandez-Villanueva, Alfredo Ausencio, 1958- January 1987 (has links)
Experimental and analytical investigations were conducted to evaluate the overall stability for the final slope of the Pit Number One at El Encino mine, an iron ore property in Jalisco, Mexico. Shear strength of the intact rock and fractures was estimated from laboratory tests and back-analyses of previous slope failures. Back-analysis estimates were found to be more appropriate to represent the shear strength of fractures. Equal-area stereoplots were used to analyze geological structure data to differentiate structural domains with similar structural characteristics within the final slope. A kinematic analysis was performed for each structural domain using average joint set orientations and major discontinuities projected onto the final slope. The final pit walls were found to be stable, except for a 36,000 ton wedge and a 12,000 ton plane shear slide. These geometries and other potentially unstable areas were analyzed, and control measures and additional work suggested.
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Cost-effective strategies for dust control in an opencast coal mineAmponsah-Dacosta, Francis 03 March 2015 (has links)
Thesis (M.Sc. (Engineering))--University of the Witwatersrand, Faculty of Engineering, 1987.
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Development of a mining model and a financial analysis for the Entuba Coalfields - ZimbabweBotha, Quentin January 2016 (has links)
Master of Science in Engineering by advanced coursework and research: A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering
Johannesburg, 2016 / The mining sector plays a significant role in the economy of Zimbabwe. The mining sector is the second largest contributor to the country’s GDP at over 20%. Zimbabwe as a country is endowed with abundant mineral resources. The top three commodities in terms of estimated resources are iron ore, coal and platinum with resources of 30 billion tonnes, 26 billion tonnes and 2.8 billion tonnes respectively. Zimbabwe’s vast mineral resources and reserves are of strategic importance to the Zimbabwe economy. Coal mining is one of the major economic contributors to the mining industry in Zimbabwe.
The purpose of the study is to determine the optimal operational model for Makomo Resources from a mining and processing point of view. The study is based on a coal-mining project in the Zimbabwean mining industry. Makomo Resources is the largest privately owned coal mining company in the country, which has a mining licence to perform coal-mining activities in the north-west part of the Bulawayo Mining District of Zimbabwe. Makomo Resources applies a conventional strip mining method by means of truck and shovel to extract the coal reserves. Makomo Resources is supplying over 200,000 tonnes of coal per month to the local and export market.
The mine has invested in USD20 million capital to commission a wash plant. The study investigates how to optimise the plant throughput by comparing two mining options:
Mining Option 1 - crush and screen 2m power coal, crush & screen and wash a full 7m low ash coal seam and wash 2m of coking coal.
Mining Option 2 – crush and screen 2m power coal, crush & screen a 3m low sulphur coal seam and wash low ash coal and coking coal of 4m and 2m respectively.
The study investigated all the marketing, geology, mining and financial parameters in the Zimbabwean coal mining context. The study determines the appropriate mining methodology and explore to optimise the coal processing. Two financial models were developed to evaluate and compare the two proposed mining options, determine their feasibility and conclude the optimal mining model. Financial techniques were used to analyse and evaluate the two mining options.
The financial models were used to analyse and evaluate the following:
The cashflow over the 10-year period.
The Net Present Value (NPV) and Internal Rate of Return (IRR) of each mining option.
The payback period of the washing plant.
Profitability Index per mining option.
The NPV of a project determines the economic value of the mining project. The decision on a mining investment is mostly related to the NPV and IRR of the project.
Discounted Cash flow (DCF) models were developed for both mining options that shows project cash in and out flows and calculates economic indicators, such as IRR and NPV. The NPV and IRR were the main methods for the evaluation of the two mining options. The resulting DCF models were developed in an Excel spreadsheet format designed for a 10-year Life of Mine (LOM) period. Mining Option 1 has a higher NPV of USD38.2 million in comparison to USD9.7 million for Mining Option 2. The IRR for Mining Option 1 was calculated at 48%, which is bigger than the IRR for Mining Option 2 of 26%. Mining Option 1 has a simple payback period and discounted payback period of 2.7 years and 4.9 years respectively. Mining Option 2 has a simple payback period and discounted payback period of 3.9 years and 11.9 years respectively. Mining Option 1 has a shorter payback period than Mining Option 2. Both mining options have a Profitability Index (PI bigger than one with
Mining Option 1 and Mining Option 2 recording values of 1.87 and 1.18 respectively. Mining Option 1 has the better PI value and is therefore more profitable.
Based on the economic evaluation, Mining Options 1 is by far more attractive than Mining Option 2, which results in a better return on the investment and profitability, therefore the preferred option. / MT2017
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Remote sensing techniques for monitoring coal surface mining and reclamation in the Power River BasinAlden, Matthew G. January 2009 (has links)
Thesis (M.S.)--Ohio University, November, 2009. / Title from PDF t.p. Includes bibliographical references.
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Functionality assessment of a reconfigurable vibrating screen.Makinde, O. A. January 2014 (has links)
M. Tech. Industrial Engineering / The Reconfigurable Vibrating Screen is a newly designed beneficiation machine to be used for mineral particle separation in mines and quarries with adjustable screen capacity and structure in order to respond to changes in production and quantity demand required by the customers. In order to increase the durability, availability, reliability and maintainability of a reconfigurable vibrating screen, an effective method is required to functionally appraise and improve its working condition. The aim of this study is to develop a tool for functionally assessing reconfigurable vibrating screens and existing vibrating screens.
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Dispatching vs. nondispatching of trucks at open-pit minesIbarra Navarro, Miguel Angel January 1980 (has links)
No description available.
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The development and application of a 3D geotechnical model for mining optimisation Sandsloot open pit platinum mine South Africa.Bye, Alan Russell. January 2003 (has links)
Detailed geological knowledge is often a major unknown factor in open pit mining and design, and
therefore poses a significant risk in the mining venture. As the knowledge of the geology improves
so the risk of unforeseen conditions reduces and therefore safety and productivity can be increased.
Historically, geotechnical methods and information have predominantly been used exclusively for
pit slope optimisation. This research documents the procedures and developments undertaken to
compile a comprehensive geotechnical database, and the application of the geotechnical data to
open pit mining, beneficiation and planning. The utilisation of the geotechnical information has
been enhanced through the novel development and application of a computerised, 3D geotechnical
model.
Sandsloot open pit was developed to extract the Platreef pyroxenite orebody, which is hosted within
the Northern Limb of the Bushveld Complex. Sandsloot is currently the world's largest open pit
exploiting Platinum Group Metals. Interaction of the basic magma with the footwall sediments of
the Transvaal Supergroup and varying degrees of assimilation has resulted in a unique suite of
hybrid rock types. These various rock types provide significant engineering geological challenges.
Geology and the detailed understanding of its properties are fundamental to the optimal design and
successful operation of any mine. Extensive fieldwork was conducted to collect geotechnical
information, both from exploration boreholes and in-pit mining faces. Over a 5-year period,
geotechnical data were collected from 29,213 m of exploration core and 6,873 m of exposed
mining faces. Extensive field and laboratory testing was undertaken in order to define the complete
set of geotechnical properties for each rock type in the Sandsloot mining area.
The geotechnical information relating to each borehole and facemap was stored in the Datamine®
software package. The information was collected in the form of rock mass rating (RMR), uniaxial
compressive strength (DCS), fracture frequency (FF/m) and rock quality designation (RQD). The
architecture of the database was developed along the principals used for generating an ore reserve
model.
One of the novel applications was the development of a computerized 3D, geotechnical model in
Datamine®. The geotechnical parameters, namely RMR, DCS, FF/m and RQD, were modelled for
each rock type, using geostatistics, to generate a 3D model. The data were interpolated between
exploration boreholes and exposed mining faces and the modelling was constrained using
wireframes separated by rock type. The result is a 3D model containing 15 m3 model blocks
populated with interpolated geotechnical information. The dimensions of the model blocks are
linked to the mining bench height of 15 m. The model can be queried to give predictions on rock
mass conditions for any planned mining area, as is the case with the ore reserve model, which
provides predictions on platinum grades.
The crux of the innovative research is the practical application of the 3D geotechnical model. This
was achieved through the development of both a fragmentation and a slope design model, which
read the interpolated geotechnical information. These models provided an engineering tool to optimise mining and milling perfonnance.
Rather than viewing the drill and blast department as an isolated cost centre and focussing on
minimising drill and blast costs, the application of the model concentrated on the fragmentation
requirements of the milling and mining business areas. Two hundred and thirty-eight blasts were
assessed to detennine the optimum fragmentation requirements for ore and waste. Based on the
study a mean fragmentation target of 150 mm was set for delivery to the crushing circuit and a
mean fragmentation of 230 mm was set for waste loading from the pit.
The mine operates autogenous mills, which are sensitive to the fragmentation profile delivered.
The harder zones occurring in the ore zone have a major impact on the plant's perfonnance. The
geotechnical parameters in the model were related to Lilly's Blastability Index, and in turn to
required explosive volumes and the associated drill and blast costs. Having defmed the
fragmentation targets, the Kuz-Ram equation was used in the fragmentation model to predict the
explosive volumes required to ensure consistent mining and milling perfonnance. The
geotechnical model is used to predict changes in geotechnical conditions and therefore the blasting
parameters can be adjusted in advance to ensure the milling and mining fragmentation
requirements are met. Through the application of the fragmentation model over an eighteen-month
period the loading and milling efficiencies improved by 8.5% and 8.8% respectively, resulting in
additional revenue ofR29 million for PPL.
Based on the mining rock mass rating (MRMR) values within the geotechnical model a stable slope
design model was created in order to calculate optimum inter-ramp angles. From a slope design
perspective the model was used to target data-deficient zones and highlight potentially weak rock
mass areas. As this can be viewed in 3D, the open pit slopes were designed to accommodate the
poor quality areas before they are excavated. It also follows that competent geotechnical zones can
be readily identified and the slope optimised accordingly.
Due to the detailed geotechnical infonnation being available in three dimensions, the open pit
slopes were designed based on a risk versus reward profile. As a significant geotechnical database
was available, more accurate and reliable designs were generated resulting in the overall slope
angle increasing by 3 degrees. This optimisation process will result in a revenue gain of R900
million over the life of the mine. The revenue and safety benefits associated with this design
methodology are substantial and have potential application to all open pit mining operations.
The research has enabled detailed geotechnical infonnation to be available in three dimensions.
This information can be readily accessed and interpreted, thus providing a powerful planning and
financial tool from which production optimisations, feasibility studies and planning initiatives can
be implemented. The development and application of a 3D geotechnical model has added a new
dimension to the constant strive for business improvement and reflects a novel and successful
approach towards the application of engineering geology at the Sandsloot mining operation. / Thesis (Ph.D.)-University of Natal, Durban, 2003.
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Petrological and geochemical analysis of coal mine spoil to determine the source of magnesium-rich groundwater, Star Fire Mine, Eastern KentuckyBarone, Jessica Lynn January 2000 (has links)
The Star Fire Coal Mine is a large strip mining operation (10,000 acre permit) that produces mine spoil consisting of sandstones, shales, siltstones, and underclays of the Pennsylvanian Breathitt Formation. Chemical analysis of groundwater from the saturated mine spoil show unusually high magnesium concentrations, with magnesium constituting between 27 and 47 percent of the major cations. Excess magnesium in water is detrimental to plant metabolism, and its content in groundwater may limit its use for irrigation and other uses during a post-mining land use plan. Petrological methods (thin section point count analysis and x-ray diffraction) and geochemical methods (electron microprobe analysis and water extraction experiments) were performed to determine the source of magnesium in sandstone and shale samples of the Breathitt Formation. Based on mineral percents and concentrations of magnesium found in samples used for waterrock interaction samples, magnesium-rich siderite was found as the primary contributor of magnesium to the groundwater. / Department of Geology
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Water-harvesting on arid coal mine soil for vegetable and fruit productionPowelson, David. January 1982 (has links) (PDF)
Thesis (M.S. - Renewable Natural Resources)--University of Arizona, 1982. / Includes bibliographical references (leaves 72-77).
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Analyse de stabilité des pentes rocheuses de la mine Troilus, Chibougamau, Qc. /Bélanger, Julie, January 2005 (has links)
Thèse (M.Sc.A.) -- Université du Québec à Chicoutimi, 2005. / Bibliogr.: f. 317-326. Document électronique également accessible en format PDF. CaQCU
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