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By F. Bourgouin

Thirty-one years ago, African leaders met in Lagos for the drafting of the Lagos Plan of Action for the Economic Development of Africa, 1980?2000. The main objective of the plan was to increase Africa?s self-sufficiency and in this regard, the plan had a section pertaining specifically to redressing the ills of an unproductive mining and minerals industry and harnessing its potential for socio-economic development. However, if we look at the nature of this sector on the continent today, its characteristics resemble the diagnosis of the sector given in the plan back in 1980: lack of information on endowments of minerals; lack of value added in the sector; low development and use of those endowments that are not of interest to transnational corporations (TNCs); and most importantly, low contribution to socio-economic development. The primary consequence of the lack of visible benefits to African states, despite growth and development of the sector in terms of increased mining activity led by Foreign Direct Investment is that countries with mining industries are characterized by dysfunctional internal processes. Improvements in governance, monitored with indices such as those set out in the Extractive Industries Transparency Initiative, the Millennium Development Goals, and other such ?good governance? agendas, are being asserted. However, before we prescribe the introduction of initiatives or guidelines based upon highly subjective norms which we believe to fit this diagnosis, it is necessary to review how it is that we got to this situation that we are in today. How is it that, 31 years after the Lagos Plan of Action, we have not seen any major changes in the role the industry can play in socio-economic development, despite the vast increase in mining activity on the continent?

Jan 1, 2011

By Neal Harries

The monitoring of rock slopes is a common procedure in the management of hazards associated with slope instability. Slope stability radar has become widely accepted as the state-of-the-art method for management of hazards associated with unstable slopes in open pit mines. This is confirmed by the rapid adoption of the technology since inception in mid 2003, with over 70 GroundProbe slope stability radars now in use at open pit operations throughout the World. The use of a monitoring system such as slope radar to identify slope hazards is only part of the solution to minimise the consequences associated with slope instability. The presence of the hazard must also be effectively communicated to the mine personnel, so that the correct response to the hazard can be enacted, and the risk mitigated to an acceptable level. In some surface mines, due to the geotechnical characteristics of the rock mass, hazards can develop rapidly; with slopes progressing from stability to ultimate collapse in just hours. In these situations, it is vital that efficient systems are developed to evacuate the area of the pit affected. Such a system has been developed by GroundProbe in South Africa, with the vital driving force for the project being provided by the Anglo Platinum Mogalakwena mine operation based at Mokopane. The mine based development of the system was perceived as an essential aspect in the development of the successful system. From an early stage, the mine provided essential input on both hardware and software developments to allow the system to be rapidly integrated into the mining operation. This paper describes the pit evacuation alarm system that was developed and discussed the benefits obtained from a mine based development program.

Jan 1, 2008

By S. Kauchali, J. van Dyk, J. Feris, S. Pershad, M. van der Riet, D. Love, J. Brand, C. A. Strydom

"This paper offers an introduction to and strategic context for the other papers included in this special UCG edition of the Journal of the Southern African Institute of Mining and Metallurgy. South Africa is facing long-term energy security challenges, brought about by a myriad of factors that are somewhat unique or exacerbated in the global context. Underground coal gasification (UCG) is a process used to produce synthesis gas from coal in situ, that is, in the coal seam. UCG is an emerging, advanced clean coal technology that offers a potential solution for these challenges, as it can cost-effectively and cleanly liberate vast coal resources in the country that currently cannot be economically exploited using traditional mining technologies. One of the tasks of the South African Underground Coal Gasification Association (SAUCGA) is to advance the development of UCG in South Africa by compiling a technology roadmap. This paper presents the initial findings of the SAUCGA Roadmap (Draft), and contextualizes the technology opportunities and challenges, stakeholders, and provides a basis from which to progress further plans for technology development. Firm development plans and deadlines are not yet possible due to the reliance of the UCG Roadmap on the higher level South African energy policy and regulatory framework. However, the draft roadmap has taken the first step of identifying these policies and stakeholders, and should be seen as the seed from which this embryonic technology and industry can be further developed. IntroductionSouth Africa’s long-term energy security challenges include energy access and affordability, dwindling reserves of accessible bulk primary energy, mounting environmental concerns with all forms of energy generation (especially coal and nuclear), balancing the electricity grid by incorporating an increasing proportion of non-despatchable renewable energy sources, mounting environmental liabilities regarding defunct mining operations, and lastly but by no means less important, fluctuating exchange rates and energy commodity prices.Correctly managed underground coal gasification (UCG) is an emerging, advanced clean coal technology that offers a potential solution for these challenges, as it has been shown to have the potential to cost-effectively and cleanly liberate vast coal resources in the country that currently cannot be economically exploited using traditional mining technologies."

Jan 1, 2019

By T. P. Katakwa

The utilization of software is now inherent to virtually every activity along the mining value chain. However, apart from the software survey done by Gibbs in the 1990s and work on the extent of diffusion of information and communication technology (ICT) in the South African platinum sector by Mugodi and Fleming in 2003, the nature and extent of software utilization in the South African mining industry has never been evaluated. The Mine Planning, Optimisation and Valuation (MPOV) Research Group in the School of Mining Engineering, University of Witwatersrand, therefore initiated a project to collate and analyse the current utilization of software in the South African mining industry. This was done through the development of a web-based database of the relevant software. Snowball sampling was used to collect the data because the South African mining industry is diverse and software utilization is fragmented across and within the sectors of the industry. The data was then organized into distinct categories so that the information from a variety of sources could be evaluated on the same basis. A beta version of the database can be accessed online through a user-friendly front-end platform at http://db.mining.wits.ac.za. The database is expected to help at least 13 educational institutions with decisions on facilities and training that are vital to the education of mining and mining-related professionals. Exploration, mining, and consulting companies will also benefit from information in the database relating to availability and useful combinations of software solutions. The database is also strategic to software providers by providing a better understanding of their respective relative market share along the mining value chain. An analysis of the data collated in this research shows that about 77% of the software users are mining companies, 17% are consulting companies, 3% are mineral exploration companies, and the rest are software providers and educational institutions. The software used in the South African mining industry is largely provided by Gemcom Software International, MineRP Solutions, and MRM Mining Services. CAE Mining, who in 2010 acquired the Datamine Group providing Datamine software, is also widely acknowledged as a major software supplier in South Africa, but data from them had not been obtained at the time of producing the beta version of the database due to proprietary constraints. The work reported in this paper is part of an MSc research study in the School of Mining Engineering at the University of the Witwatersrand. Keywords mine planning, mining, value chain, software, database, South African mining industry, utilization.

Jun 1, 2013

By J. Ning, T. Bu, J-Q. Jiang, L. Jiang

"In coal mining in China, the cutting height of the shearer in longwall faces is increasing. Owing to the increase of extraction height, the caved roof strata area is enlarged, and new issues are being encountered, such as determination of a suitable working resistance for the shield and control of the roof. Through field observation and theoretical analysis of the first longwall face with a height of 6.0 m in the Bayangaole mine, a three-stage structural model was developed. Stage I is defined as the period in which the lower immediate roof (LIR) caves into the goaf and is broken into irregular shapes of various sizes. Stage II is defined as the period in which the upper immediate roof (UIR) breaks and impacts the LIR. In stage III, the main roof breaks into blocks and then impacts the UIR. With respect to these three stages, a suitable method was identified for calculating the working resistance of the shield support for a super-great mining height longwall face (SGMHLW). Introduction and backgroundThe coal seams in the Shendong coalfield, located in the northwest of China, are characterized by low dips and large thicknesses and are thus suited for full thickness extraction. Since the mid-1990s, the Shendong coalfield has been developed into one of the largest in the world (Ning, Liu, and Tan. 2014; Ning et al., 2017). Recent developments in mining equipment have made it possible extract entire seams up to 5.0 m thick in a single cut. This method, termed the ‘super-great mining height longwall face’ (SGMHLW) method, has been widely adopted in the Shendong coalfield (Table I) (Ju and Xu, 2013; Peng, Li, and Zhou 2015; Zhang, Fan, and Ma 2011). According to some studies, sudden support-closure incidents often occur when using the SGMHLW method. The key to solving this engineering issue is to have a clear understanding of the structural characteristics and movement laws of the overlying strata. For instance, the load on the supports is related to the movement of the roof stratum as a response to the mining activities."

Nov 1, 2018

By M. Kumral, S. Hmoud

Optimising the configuration of infill drill holes is an important step during mineral exploration campaigns. However, this optimisation process encompassing all possible drilling configurations within a mineral deposit is highly combinatorial and hard to solve in a reasonable time. This paper proposes using spatial clustering algorithms to divide the orebody into contiguous zones and target the best zones with infill drilling in order to reduce the size of this optimisation problem. Several clustering algorithms are assessed in a spatial context on hypothetical datasets. This evaluation shows that the hierarchical density-based spatial clustering application with noise (HDBSCAN) algorithm can be used in combination with the uniform manifold approximation and projection (UMAP) dimensionality reduction algorithm to identify contiguous zones in the orebody.

Sep 1, 2021

By S. W. Jacobsz, E. P. Kearsley, N. K. Schoeman

A physical modelling approach was adopted to simulate the process of cave mining propagation at various horizontal to vertical stress state ratios, and image data was captured and used to characterize the resulting failure mechanisms. Image processing was integrated into the study to determine minor principal strains in models to identify where critical extensional strains had been exceeded relative to crack propagation. The study exhibited a scale factor magnitude of 119 using a calculated critical extensional strain value of 0.014% for the modelling material used. It was perceived that cave propagation occurred through successive parallel extensional ‘fracture bands’ in all cases, as noticed in models of prior studies, deviating from that described by the Duplancic model. Cracks tended to bisect regions of minor principal strain equal to the critical extensional strain, which suggests ‘fracture banding’ is an acceptable failure mode for brittle, rock-like materials. Moreover, it was found that models with lower horizontal to vertical stress ratios (K ratios) showed a greater degree of vertical development of the caving mechanism (at similar vertical stresses), while the vertical extent of the cave was suppressed in models with higher K ratios. Models subjected to larger vertical stresses experienced slower cave formation in latter time-steps. These models exhibited larger two-dimensional caved perimeters and areas, respectively.

Nov 30, 2022

By E. Mpoloka

Debswana together with ADP as their design partner have embarked on an RDP project at Jwaneng Mine. The objective of the project is to install a 2 million ton per annum mineral processing plant that will fast track the recovery of diamonds from the Debswana tailings resource to ensure maximum return on investment for the company. Due to the prevailing economic conditions Debswana has had to review the way they used to build plants in the past and consider simple, fast and effective ways of doing things. The rapid deployment plant concept is therefore the most suitable means of achieving this objective. Debswana is also considering an operating partner who will operate far more efficiently and cheaply compared to the larger more cumbersome and less agile Debswana.

Jan 1, 2010

By C. Pamukcu

In this paper, which is aimed to serve as a review article, first of all a breakdown of the earth?s total water reserves is given. The usage areas of water in the mining industry are mentioned and these uses are briefly outlined, together with the main pollution potential of each. According to this, most of the water (almost 80% of it) is utilized in processing. Later on, probable damages that the mining would give to groundwater as a result of acid mine drainage, heavy metal pollution, euthrophication and deoxygenation is described. Finally, the measures and controls that should be taken against water contamination in mines are presented.

Jan 1, 2008

By N. J. Roodt

Mine dumps created in terms of the pre-MPRDA regime (old order mine dumps) are currently not regulated by the MPRDA, and the common law owners of such dumps are free to process them without the need to obtain the relevant rights. The MPRDA Amendment Act purports to change this position. However, the wording of the Amendment Act raises a number of problems which render the post-amendment position at best unclear and at worst absurd and unworkable. The primary concern with the Amendment Act is that, on one interpretation, material placed on the same dump at different times may be treated differently at law. Thus, parts of a dump may be subject to one person?s right while others may be subject to another?s right. Moreover, case law has generally regarded mine dumps as movable property and, by extending the MPRDA to apply to all mine dumps, the Legislature is extending the ambit of the Act to cover movable property, a scenario not contemplated by the wording of the Act (even after its amendment) in relation to applications for rights. The better interpretation of the amendments, which are not yet in force, is that they will not apply retrospectively to old order mine dumps.

Jan 1, 2010

Determination of mineral composition is of significant importance for the mineral sands industry as this information is required for orebody evaluation, the control of mineral processing plants and the determination of product quality. Mineral processing is made more difficult by the presence of pseudorutile, leucoxene, altered-ilmenite and particle inclusions. The paper investigates the properties of such elements from a single product stream using an MLA approach.

Jan 1, 2007

By D. E. Kraushaar

Ruhrkohle in West Germany evaluates and compares the net present values of long-term periods from its coal mines by a computer assisted long-term planning system. Two main parts of this system are computer programs for the prediction of: (a) mineable reserves and their distribution in longwall panels as a function of dependent geological variables; (b) daily outputs and costs of longwall panels as a function of dependent geo- logical, layout and operational variables. This paper describes the investigations, which ended in the above computer programs: ? the collection of information from past workings and their organization in databases; ? the statistical evaluation of the databases, and ? the resulting correlation formulas. The correlation formulas vary the mean dependent variables as a function of independent variables which can be indicated with high reliability for planning projects in the long run. The system thus serves the purpose of facilitating long-term planning and excluding biased individual judgement of local planning staffs.

Jan 1, 1987

By R. J. Cocks

Water auditing and water efficient practices are evolving as the quantitative tools for water balance reporting in the mining and minerals processing sector. This paper was written to describe the process of water auditing in a gold mining environment. It will contribute towards building an appropriate water management framework for The Cooperative Research Centre (CRC) for sustainable resource processing (CSRP). The research assists with the assessment of water balances in mining and hydrometallurgical processes and provides, on the ground, steady-state data for ongoing probabilistic modeling underway at most of Newmont?s gold mine operations. Five Newmont case study mine sites including the Tanami Granites Goldmine are central to this PhD water project study. The function of the Tanami-Granites water audit exercise was to measure a controlled flow of various water quality types and set a framework to establish further research for water efficiencies and water conservation in mining.

Jan 1, 2009

By P. G. Terrazas Prado

This paper presents the results of research on the development and application of a custom-made truck cycle and delay automated data collection system (TCD-ADCS) in a surface coal mining. Truck cycle and delay field data are locally stored in trucks and then synchronized and replicated through a wireless network into a centralized server containing an already-developed integrated production management system (IPMS). The system relies on motion sensing and distance travelled in order to automatically define the cycle starting/ending points, cycle time, position, and delay time. Connectivity and communication between loading equipment and trucks are also established. Communication between the equipment operators and TCD-ADCS system is via a user-friendly graphic interface. The hardware used for the development of this system consists of a rugged touch-screen personal computer, 2.4 GHz radio transmitter antenna, and a commercial GPS receiver. The system was developed, tested, and deployed at a surface coal mine in the USA. Keywords surface coal mining, truck and shovel, data collection, information systems.

Nov 1, 2013

By S. Özgen

In this study, the possibility of beneficiation of chromite tailings in the Uckopru/Fethiye-Turkey region by a combination of hydrocyclone and multigravity separator (MGS) was investigated. The two significant operational parameters of hydrocyclone, which were diameter of the apex and diameter of the vortex, and the three significant operational parameters of the MGS, which were drum speed, tilt angle, and wash water, were varied and the results were evaluated with the central composite rotatable design. In order to produce a chromite concentrate by hydrocyclone and MGS, mathematical model equations were derived by computer simulation programming, applying the least-squares method using Minitab 15. Second-order response functions were produced for the grade and recovery of chromite concentrates.

Jan 1, 2012

By R. M. Kear

The Mine Planning Department of Rio Tinto Management Services South Africa has installed an interactive graphic work station to assist with the long- term mine planning of Palabora. Previously, the planning was drafted manually after which digitised areas were fed to the computerised ore reserve system. This method was slow, tedious, prone to error and was becoming incapable of meeting new planning parameters. To assist the planning engineer an interactive graphic system was developed, and subsequently a rewrite of the ore reserve reporting system was incorporated. The work station has reasonable computing power and, when not utilised for graphics, has been found suitable for the evaluation of various non- graphical applications, a recent example of which was the in-pit crusher investigation. This project, in contrast to similar studies, was not based on a fixed system throughput but rather on a well designed system which would be operated at its own optimum capacity. In order to determine the probable throughput a simple simulator was designed to model the crushing and conveying system. This paper describes the investigation into the specifications for the work station, the selection of hardware, operating system and languages. An over- view is then given of the graphic planning system. The in-pit crushing simulation has been included as an example of how the work station has been applied to other, non graphical, applications.

Jan 1, 1987

By J. Grobler, J. Zietsman

"Understanding the influence of feed material mineral assemblage on spiral separation is paramount for the successful and consistent operation of a spiral plant. Plant stability is required to maintain high recovery of valuable heavy minerals (VHM). Standard material analysis methods used in the heavy mineral industry to evaluate spiral separation behaviour are unable to quantify performance differences in the case of large variations in feed assemblage. This study illustrates a systematic approach to evaluate spiral separation performance. This technique was applied on a four-stage spiral plant. The performance information was used in a circuit simulation to clearly illustrate the importance of correct setting of the spiral splitter position and resulting spiral mass loading to ensure optimal circuit stability and maximum VHM recovery.IntroductionHeavy mineral sands deposits generally consist of naturally fine-grained, free-flowing sand due to the way in which the deposit was formed. The size of the heavy minerals market is roughly 8 Mt/a of zircon and titanium combined (Iluka, 2013). If an average combined feed grade of 5% zircon and titanium and an average combined overall product recovery of 80% are assumed, the resulting run-of-mine feed tons that would require primary spiral beneficiation is 200 Mt/a. The number of spirals required for the processing of this material, assuming 6500 operating hours per annum, an average of 2 t/h per start, and the same number of rougher spirals as other duty spirals, is over 30 000 spirals for the heavy mineral sands business alone. These numbers clearly illustrate the importance of the spiral in the heavy mineral industry.The aim of a spiral plant in the primary processing value chain of a heavy mineral process is to reject non-valuable quartz (a light mineral) from various valuable heavy minerals (VHM). The product from the spiral plant is a heavy mineral concentrate that has a reasonable grade (more than 90% heavy minerals) at a reasonable heavy mineral recovery (greater than 90%). This benchmark is fairly easy to achieve if all the mineral particles are well liberated (as in the case free-flowing sand), the feed is properly deslimed (-45 µm fraction removed to less than 5% of the solids mass), and the spirals are fed within design solids concentration (water to solids ratio) and design spiral load (dry tons per hour per start)."

Jan 1, 2017

By V. Matou?ek

The paper addresses pipe flows of aqueous medium-sand slurries at velocities lower than the deposition-limit velocity. Laboratory test results including measurements of particle concentration distributions are used in order to describe a flow with a (pseudo-) linear concentration gradient above a stationary bed. Particle dispersion within the flow is evaluated and a stratification-ratio equation is formulated, estimating a portion of contact load in the flow. The formula is incorporated in the proposed predictive model for the hydraulic gradient for a medium-sand flow above a stationary bed.

Jan 1, 2007

By Allan Jansen, Robin Bissett

[Power-Point Presentation]

Jan 1, 2005

By D. J. Hallbom

A new graphical method termed the ?Design Curve Diagram? (DCD) has been developed to analyse non-Newtonian pipe flow data by relating the plastic Karman number to the plastic Reynolds number. Since the plastic Karman number is directly proportional to the pressure loss gradient and the plastic Reynolds number is directly proportional to the velocity, the DCD is essentially a non-dimensional pipe flow curve. This makes the DCD conceptually easier than the commonly used Hedström-Moody diagram. While, the DCD was developed for the analysis of yield plastic fluids (e.g., Bingham plastics), it is equally applicable to Newtonian fluids.

Jan 1, 2007