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By J. L. Porter

This paper takes a personal look, through the author?s own experiences, at the implementation of innovations in the narrow-seam, hard-rock mining environment of South Africa?s mining industry over the past 40 years. A number of examples are used to illustrate some of the successes and failures over this period. More importantly, the examples are used to illustrate that the bulk of the investment for these projects should have been applied in a manner that could have achieved more sustainable results. The use of the word ?technology? in this context is also examined, as it is the author?s contention that only measuring the performance of machinery fails to encapsulate the potential of the entire system describing the scope of the innovation being implemented. These experiences and observations are projected onto the current backdrop of upheaval in the relationship between key industry stakeholders and the sustainability challenges facing areas of the mining sector in the South African economy. The paper concludes with some opinions on where attention can be focused in order to develop new thinking that can be applied for the safe and economic extraction of the nation?s mineral wealth.

Jan 1, 2014

By W. J. Jordaan

The ability of soils to retain and hold cations is called the cation exchange capacity (CEC). Adsorbed cations, however, can be replaced by other cations through the process of cation exchange. Heavy mineral deposits contain a significant portion of slimes including the very fine clay minerals. In most circuits the slimes fraction hampers efficiency and has to be removed during early stages of the process. Being a nonvaluable process stream, the processing of the slimes is a costly exercise. In thickening applications it might be possible to manipulate the ability of clay minerals to retain and hold positively charged cations in order to optimize flocculation and therefore reduce flocculation costs. The CEC value of the slimes could be a measure of this possibility. To investigate this hypothesis, different slimes samples were characterized for size, chemical composition and clay minerals present. The CEC value of each sample was determined and explained in terms of the mineral phases present. Settling tests were conducted and an attempt was made to explain the CEC characteristics of the clay minerals in terms of settling rate. The scope of this investigation was to test the hypothesis and should not be seen as an in-depth study of the subject matter. A greater number of samples and detailed analyses to identify and quantify minerals and phases present would be required to investigate further the relationships between clay minerals in the deposit, CEC and settling rates. Location and geological setting Exxaro KZN Sands is mining a heavy minerals deposit at Hillendale mine located at Richards Bay, South Africa. The orebody consist of a dune some 8 km inland from the coast to the north of eSikhawini. A geological synopsis undertaken by Botha1 concluded that the Hillendale mining area represents a coastal dune sequence that accumulated north of the Tugela River. The northward movement of sediment by long shore drift currents result in a high sand budget on the beaches north of the river youth and is the dominant contributing factor to the accretion of the coastline and development of parallel dune systems along the coastal zone in this area. Beach swash zone processes and enrichment of the fine sand fraction occurs during wind transport off the beach by ascending parabolic dunes that form the coastal barrier dunes. This process results in heavy mineral concentration on the windward dune face and localized enrichment parallel to the dune forms. The aeolian sedimentary facies processes result in the primary concentration of higher grades in the upper silt-enriched reddish brown horizons of the profile. The synopsis by Botha1 further showed that an additional component of heavy mineral concentration can be ascribed to the post-depositional relative enrichment of heavy minerals due to weathering. Therefore, it is likely that the Hillendale orebody protolith was pedogenically weathered to form the homogeneous, silt-enriched, clayey reddish brown to dark red, palaeosol profile that grades downwards into yellowish brown, less clay-enriched sand. Slimes characterization Samples The Hillendale orebody was divided into geochemically discretized zones based on the concentration of ilmenite and other specific minerals and/or phases. Six composite samples were made up from exploration samples taken from Zone 9, Zone 11 and Zone 12. The red and orange horizons within these composite samples were separated and test samples were prepared to conduct test work and analyses. The test samples were submitted for preparation and analysis to characterize the slimes properties. Each test sample was deslimed at 45 µm representing the slimes fraction (-45 µm) and dried at 40°C. The -45 µm slimes samples were then split to conduct size analysis, chemical analysis, XRD and to determine the CEC. Size analysis The size distribution of the composite samples is shown in Table I. The size analysis shows that there is a difference in size distribution between the orange and red horizons of each zone. The orange horizons contain less 850 µ material as well as less slimes (-45 µm). The red horizons contain yore slimes (-45 µm). The size distribution of the slimes fraction (-45 µm) was determined using Malvern size analysis. The cumulative particle size distribution of the slimes is shown in Figure 1. The red horizons of the different zones show similar size distributions. The orange horizons show some differences. However, there is a difference in size distributions between the red and orange horizons.

Jan 1, 2007

By E. Lwamba

The aim of this study was to examine the effect of grain size distribution control of the raw material mixture on the permeability of the green sinter bed and the properties of the produced sinter. This was achieved by evaluating the granulation characteristics of the sinter mixture (moisture content, granulation time and mean granule diameter) in terms of its green bed permeability, and evaluating the productivity of the sinter bed, the coke rate, tumble index (TI), abrasion index (AI), reduction disintegration index(RDI) and reducibility (RI) of the produced sinter. The raw sinter mixtures contained combinations of Thabazimbi iron ore, Sishen iron ore, coke, lime and return fines. The grain size distributions were controlled by removing the ?0.5 mm size fractions of the return fines and coke, and the ?1 mm size fraction of lime. Of the examined mixtures, a mixture of 20 mass% Thabazimbi iron ore, 80 mass% Sishen iron ore and fluxes where the coke, lime and return fines were all sized had the highest granulation effectiveness and permeability. The sintering properties of the mixtures in which the grain size distributions were controlled, were very similar for all the mixtures, but superior to the base case mixture in which the grain size distribution was not controlled. Keywords: Thabazimbi iron ore; Sishen iron ore; granulation, permeability, grain size distribution; sinter.

Jan 1, 2008

By M. Kamali

In this research, in order to predict the peak particle velocity (PPV)(as vibration indicator) caused by blasting projects in the excavations of the Karoun III power plant and dam, three techniques including statistical, empirical, and neural network were used and their results were interpreted and compared. First, multivariate regression analysis (MVRA) was used as statistical approach. Next, PPV was predicted using some widely used empirical models. Lastly, an artificial neural network was used. In the ANN model, maximum charge per delay, total charge per round, distance from blast site, direction of firing, blasthole length, number of blastholes, total delay in milliseconds, number of delay intervals, and average specific charge were taken into consideration as input parameters and consequently the PPV as output parameter. The results of the techniques were interpreted from two points of view. Firstly, the correlation between the observed data and predicted ones, secondly the total error between observed data and predicted ones. The MVRA had a satisfactory correlation but its error of estimation was comparatively very high. The empirical model had reliable correlation and a small error of estimation; in total the results of empirical method were more reliable than those of MVRA. Generally, the ANN approach showed very high correlation and a very small error. The results of this research indicated that the ANN model is the best predicting model for PPV in comparison with other approaches.

Jan 1, 2010

By Z. Khan

Iron, in the form of steel and stainless steel, is the most commonly used metal in the world. Plain steels corrode and oxidize easily, while stainless steels exhibit improved corrosion and oxidation resistance. It has been found that rare earth metal (REM) additions, such as cerium and erbium, result in the improvement of the abovementioned properties in iron-containing compounds. Gadolinium is a REM, however, there is very little information available on the influence of gadolinium on the microstructure and mechanical properties of iron-containing compounds. Thus, the purpose of this research project was to determine the influence of gadolinium additions on the microstructure and mechanical properties of mild steel and 316 stainless steel. Ten alloys were produced for the purposes of this research. Five of the alloys had a base composition of mild steel while the remaining five had base composition of 316 stainless steel. The alloys for each of the base composition contained gadolinium additions of 0.1, 0.5, 1.2, and 5 weight per cent. The as-cast and the cold-rolled alloys were analysed. The alloys responded well to the cold-rolling with the exception of the 5 weight per cent gadolinium mild steel and stainless steel alloys. These alloys were extremely brittle and underwent a significant amount of cracking during the cold rolling process. A microstructural analysis of the alloys was conducted using a light optical microscope, while the chemical analysis of the alloys was conducted using energy dispersive x-ray spectroscopy (EDS). The resulting microstructures and EDS analyses revealed that the gadolinium displayed minimal solubility in the ferrite matrix of the mild steel alloys and minimal solubility in the austenite matrix of the stainless steel alloys. Instead the gadolinium formed as an interdendritic secondary phase in both alloys. EDS analysis revealed that the secondary phase in both alloys was gadolinium-rich. Vickers microhardness tests conducted on both alloys revealed that the alloys were composite-like, with a hard, brittle gadolinium-containing compound dispersed throughout a softer, more ductile matrix. The corrosion resistance of the alloys was determined through potentiodynamic anodic polarization tests. Two solutions were used for the corrosion rate tests: a 0.5 weight per cent NaC1 solution and a 0.5 M H2SO4 solution. The results from the mild steel alloys revealed that in both the solutions, the corrosion potentials and the corrosion resistance of the alloys increased with increasing gadolinium concentration up to 1 weight per cent. The corrosion rate test results from the stainless steel alloys revealed that the passivation current density and corrosion resistance of the alloys increased with increasing gadolinium concentration in both solutions. The oxidation resistances of the mild steel and stainless steel alloys were determined through the use of a Netzstch Simultaneous Thermal Analyser. For both the mild steel and the stainless steel alloys, it was found that the oxidation resistance of the alloys increased as the concentration of gadolinium increased when compared to the as-received mild steel and stainless steel samples. This could be due to a strongly adhering gadolinium oxide scale that formed on the surface of the alloys and resulted in the protection of the mild steel and the stainless steel.

Jan 1, 2012

By Y. Wang

Arsenic-bearing acidic effluent from hydrometallurgical processes contains many harmful metal ions and must be appropriately treated before discharge. In the present study, arsenic, copper, zinc, aluminum, and magnesium were co-precipitated by means of the Fenton reaction. The precipitates obtained under different conditions were investigated to determine their stability. The results indicate that pH value and hydrogen peroxide (H2O2) dosage have significant effects on the removal of various elements. Arsenic, copper, zinc, and aluminum (but not magnesium) can be removed at pH 5–6 and anH2O2/As mole ratio of 2 at ambient temperature. The precipitates were mainly amorphous and granular with particle size in the micrometre range. The arsenic concentration in leachate from the toxicity characteristic leaching test was 3.6 mg/L, which proves that the precipitates are effective in fixing arsenic.

Aug 3, 2023

By A. Chagnes

This paper presents a modelling tool that can be used to predict the behaviour of solvent extraction processes. In particular, this model allows calculating metal extraction efficiency as a function of pH, solvent flowrate, stripping flowrate and aqueous feed flowrate in the mixers-settlers. This model is applied to the recovery of cobalt from acidic chloride media by using CYANEX® 272 as extractant diluted in kerosene. Keywords: Cobalt, mixer-settler, modelling, solvent extraction

Jan 1, 2020

By Stephen Yirenkyi

The mining industry remains the backbone of many economies in the developing world. Its resurgence in Ghana since 1989 was driven by the global paradigm which emphasizes private sector-led development as the engine of economic growth in developing countries. The historical importance of mining in the economic development of Ghana is evident in the country?s colonial name, Gold Coast (Akabzaa T. and Darimani A., 2001). Ghana earned $2.5 billion from mineral exports in 2007. 20,000 people are employed in large-scale mining whilst 500,000 are employed in the small-scale sector. Mining contributes about 7% of Ghana?s total corporate tax earnings, 41% of total exports, 12% of revenue collected by the Internal Revenue Service and 5% of Gross Domestic Product (Ghana Chamber of Mines, 2008). Gold dominates the mining sector and the country is Africa?s second largest gold producer after South Africa. Surface Mining, which refers to a method of extracting minerals from the earth by their removal from an open pit or borrows, requires a large tract of land for its operations (Wikipedia, 2008). There is therefore a continuous divergence of interest between land required for surface mining and other land uses such as farming and housing, among others. In recent years, surface mining has been promoted in many mining countries because of the following reasons: ?Cost considerations compared to underground mining; ?Safety considerations, compared to underground mining; ?Low grade ore which requires processing huge quantities; ?Location of the ore bodies; and ?Competition among gold producing countries for investors. This paper looks at the socio-economic impacts and challenges of surface mining by using Gold Fields Ghana Ltd. Tarkwa, Ghana as a case study. The company has a concession of about 208 sq km located in the heart of the Wassa communities in the Western Region of Ghana and undertakes surface mining like most of the other mining companies in the country. Gold Fields, Tarkwa mine produces 700,000 ounces of gold a year with the potential of increasing this output to 800,000 ounces after its current expansion programme. Some of the effects of surface mining identified were: 1. Relocation/Resettlement of host communities and its negative effects; 2. Disturbance to Flora and Fauna; 3. Disturbance to Sacred Places; 4. Land Degradation; 5. Noise and Air Pollution; and 6. Water Pollution. This paper sought to investigate the measures put in place by the government and the Gold Fields Ghana Ltd. to mitigate the above effects in order to ensure peaceful coexistence between the mining company and its host communities. It concludes that most mining companies presume the provision of socio-economic development in mining communities will lead to the company securing a social license to operate. This however is not true but rather effective community relations combined with socio-economic development. According to Gold Fields Ghana Ltds. model, this involves continuous community engagement, conflict resolution and comprehensive environmental monitoring programme which will all lead to effective community relations. The strategies to ensure socio-economic development involves community development programme, livelihood restoration programme and community training and employment. All these will then lead to sustainable development which will ensure the company?s social license to operate. Gold Fields? model is in line with the principles of responsible mining. With this model, the community feels they are part of the company and the social license of the company is guaranteed. Gold Fields? model, which has been tried and tested for the past five years, could serve as a template with suitable modification for local conditions for other mining countries where surface mines operate.

Jan 1, 2008

By K. Arnold

AngloGold Ashanti has been proactive in the field of energy management for many years. AngloGold Ashanti is a signatory to South Africa?s National Energy Accord of 2005 calling for a15% reduction in energy consumption by 2015 for the mining sector. This target also supported our internal targets that were already set. AngloGold Ashanti?s seven South African mines consume on average 440 MW. Due to the dynamics of gold mines, and the large numbers of relatively small energy efficiency initiatives and awareness campaigns made measurement and verification of energy efficiency very difficult at a macro level since some initiatives could get lost in the fluctuating load profile. This paper will discuss the methodology and process followed to quantify the impacts of the combined energy efficiency initiatives at macro level. It will quantify the energy efficiency impacts in megawatt-hours (MWh), financial, and equivalent carbon emissions (CO2e) reduction with reference to our baseline year, 2004, for the Vaal River and West Wits mine clusters.

Jan 1, 2009

By George Kayesa

[ ] A multiple-bench slope failure occurred at Letlhakane mine on 14th July 2005. No injuries or damage to equipment was suffered and mining production was not affected. Slope failure was preceded by the precursors of tension crack formation, crack widening and extension as well as slope monitoring targets movement. It was predicted that slope failure was imminent using the Geomos slope monitoring system, though the timing was not certain. The area to be affected by the slope failure was also known before hand as was the slope failure mode. As a result, measures were taken to avoid exposing personnel and mining equipment to the slope failure risk. This paper discusses how the prediction of the slope failure of 14th July 2005 using the Geomos slope monitoring system resulted into avoiding potentially fatal injury, damage to mining equipment and loss of mining production.

Jan 1, 2006

By D. Vogt

South African underground hard rock mines are typically managed using measurements made daily, weekly or even monthly of key parameters such as face advance, readiness to blast, blast success, temperature or dust levels. Safety and health can be greatly improved if a real-time measurement system can inform decision making. To enable this vision of widespread sensing, communication and decision support, CSIR has developed an open standard architecture for communication of sensor data, and a reference implementation using that standard. The standard is called AziSA, which means ?to inform? in isiZulu. AziSA provides an architecture that allows for connection of any type of sensor and that is particularly suited to wireless sensing. On the safety side, the CSIR is developing a suite of sensors specifically around the risk of rockfalls. Sensors such as an electronic replacement for the barring tool, or a thermal sensor that can detect loose rock, can already be used to identify potential hazards in the hangingwall. When these sensors are combined with location and time information in a single database, it becomes possible to build maps of risk and to extrapolate risk into unmined areas. It is also easy to confirm that routine safety procedures like barring are actually taking place. In the future, it is proposed that entry inspections will be made using remote techniques that will not place an individual miner at risk. While miners will still be required to bar or place support, they will do so with a clear idea of which portions of the hangingwall are safe, and which present risk. On the health side, if a network such as AziSA is deployed in the stope, it becomes much easier to monitor the condition of individual miners. The work strain experienced by miners can be monitored through heart-rate sensors, and their core body temperature can be monitored using various novel techniques discussed in the paper. Additional sensors can be added to quantify worker exposure to hazards such as noise or dust. Individual sensors allow for people who are at an unacceptably high risk of developing heat disorders to be treated timeously, and they also allow for team management based on objective measures. Over a longer period, position sensing and environment monitors, or personal dosimetry, provide a powerful management tool to prevent workers from being overexposed to hazards, and to confirm that management instructions are being followed. Cost-effective sensing in the stope is a major challenge, but one that can be overcome through technology like that used in AziSA. Sensing provides opportunities both to make immediate interventions when workers are exposed to unacceptable risk, and to manage the long-term exposure of workers to hazard.

Jan 1, 2010

By J. H. C. Pretorius, P. Nelwamondo

"Although South Africa possesses more than 80% of the world’s platinum reserves, its reputation for reliability in supplying platinum to global markets is under threat. This is due to the 49% decrease in output per worker (1999–2014), while the domestic costs have risen by more than 10% annually for the past 5 years. In addition, the continued decline in the commodity price by 38.3% (2012–2016) has resulted in a significant portion of the sector producing at a loss in 2015. The Chamber of Mines (now the Minerals Councilof South Africa) has suggested that solutions to improve productivity and reduce cost pressures are required. This research aims to provide operational excellence through the application of event chain project management (ECPM) to improve productivity and reduce operational costs. A case study was used to carry out research in platinum mines, with data collected using a motion-time study to measure the current efficiency of operations in each mining stope through actual activity durations. The results indicate that through the application of the event chain project management methodology, risks affecting the mining stope schedule can be managed, the efficiency of operations was improved by reducing the time spent on each activity, productivity was increased by shortening the project duration, and operational costs were reduced in the process. IntroductionSouth Africa’s total mining industry production was 4.9% lower in 2016 than in 2015; it decreased by 1.9% year-on-year in December 2016, with the main contributor to this negative trend being the platinum group metals (PGMs) with a drop of 15.1% and contributing -3.8% percentage points (Statistics South Africa, 2016). Although South Africa possesses more than 80% of the world’s platinum reserves, the 8% drop in production output since 2008 has put the platinum mining industry under the threat of being seen as an unreliable supplier to global markets. This decline in production is caused by the 49% decrease in output per worker between 1999 and 2014. In addition, the continued decline in the commodity price by 38.3% from 2012 to 2016 and an increase in operational costs during the same period resulted in a significant portion of the sector producing at a loss in 2015. A turnaround strategy is required to overcome these challenges. The Chamber of Mines has suggested, among others, the need for solutions to improve productivity and reduce cost pressures. The implementation of these solutions will ensure that the PGM industry thrives and reaches its potential of growing production to more than 322 t by 2020 (Baxter, 2016)."

Jan 1, 2018

By B. Genc, C. Gous

Spontaneous combustion during coal mining operations is a major problem that affects the health and safety of workers and causes environmental problems. The phenomenon is associated with the presence of coal, coal shale, and pyrite. In 2020, a premature detonation incident occurred at an iron ore mine where the waste material contains black carbonaceous shale units known to be associated with pyrite. The spontaneous combustion propensity and properties of samples of the black carbonaceous shales from the mine were examined and compared with samples from the Witbank Coalfield. The spontaneous combustion liability indexes of these samples were correlated with X-ray fluorescence (XRF) and proximate and ultimate analyses using linear regression. The Wits-Ehac Index classification results show that the samples were between medium and high risk. The linear regression analysis showed very poor correlations between the Wits-Ehac Index results and the XRF and proximate and ultimate results. The most valuable relationship found is between the presence of relatively high sulphur (greater than 3%) and ground reactivity with nitrate-bearing explosive emulsion.

Jun 5, 2023

By L. Marais

The development of a post-mining economy is generally framed as accessible and desirable and something that mining companies, consultants, and the government can, and should, plan for. It is indeed possible. Yet, most mining regions, other than the big metropolitan municipalities, find economic diversification after mining challenging, despite their grand plans, consultant reports, and company intentions. Their efforts blind them to other ideas that are often prerequisites to diversification. This paper highlights some economic and social misconceptions about economic diversification and explains where planning goes wrong. Mistakes typically stem from ignorance and misunderstandings. Planners and policy makers fail to grasp the essential requirements for economic diversification. They underestimate the structural constraints created by mining. They do not see how mine rehabilitation is linked to economic diversification. They generally do not understand the South African space economy or the nature of new economies. The paper also proposes a more careful consideration of those economic aspects that mining cities have control over, such as land use management and infrastructure. The paper further explains how understanding long-term dependencies can help prevent governance failures. The social disruption that accompanies mine decline and closure must be recognised and dealt with. The mines must plan for decline as a way to resuscitate the economy. It concludes with a framework for assessing and developing a post-mining economy.

Apr 25, 2025

By F. H. Deist, M. P. Roberts

"The Collieries Research Laboratory of the Chamber of Mines of South Africa is developing a coherent system of programs to aid in the full spectrum of activities arising in the planning of new as well as operating mining enterprises. It is the purpose of this paper to describe the design and application of two subsystems in the complex.One of these subsystems is an initial version of a production simulator. This program draws upon a model of a mining enterprise and simulates the operational and financial aspects of a set of alternative mine production plans.These plans are specified in terms of proposed sequences of operations. Details such as reserves, production rates, resource requirements and so on, are taken from the model.Physically, the model takes the form of a cross-referenced data base, maintained by means of a general file maintenance system which is another subsystem described.The paper concludes with a description and analysis of the first practical application of the two programs."

Jan 1, 2014

By A. Drumond, J. F. C. L. Costa, M. G. Lemos, A. L. Rodrigues, F. G. Niquini

The past decade has seen a renewed possibility of using machine learning algorithms to solve a large collection of problems in several fields. Data acquisition for mining operations has increased with the growth in sensor-based technologies, and therefore the amount of information available for mining applications has dramatically increased. Ore sorting equipment is available for separating ore from waste based on differences in physical properties detected by a real-time analyser. The separation efficiency depends on the contrast in these properties. In this study we investigate the application of machine learning models trained using data from the output of a dual-energy X-ray ore sorting apparatus at a gold mine. The particles were first hand-sorted into ore and gangue classes based on their mineralogical composition. Classification models were then used to help decide the balance between the number of true and false positives for ore in the concentrate, with a view to economic parameters, using their receiver operator characteristic (ROC) curves. The results showed AUC (area under the ROC curve) scores of up to 0.85 for the classification models and a maximum reward condition Fpr/Tpr around 0.5/0.9 for a simplified economic model.

Aug 8, 2024

By I. Cameron, S. Ramjee, A. M. Garbers-Craig

The cause of reduced workability and increased ageing of a blast furnace taphole clay was examined. The investigated taphole clay contained 60 mass% alumina, with phenol-formaldehyde resole resin and liquid pitch serving as the binder system. The workability and Marshall extrusion pressure of the as-manufactured clay samples were evaluated to assess the extent of ageing of the clay. The wettability of all the raw materials was investigated to confirm compatibility between the dry raw materials and both the resin and liquid pitch, while the dry raw materials were analysed using XRF, XRD, and SEM-EDS. The characterisation of the resin and liquid pitch, as well as an analysis of their interaction, was performed using viscosity measurements, Fouriertransform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The analyses confirmed a chemical interaction between the resole resin and liquid pitch, where the chemical structure of the resole resin changed when mixed with pitch, preventing the typical curing behaviour of the resin. Upon ageing of the resin-pitch mixtures, the resin underwent premature cross-linking, causing the curing process to initiate at lower temperatures, i.e., earlier onset of curing. This premature cross-linking was likely due to secondary amines present in the liquid pitch, which acted as a catalyst for the curing process of the resin. This reduction in curing temperature after ageing was confirmed by an increase in binder viscosity, which was identified as the primary cause of reduced workability, accelerated ageing, and increased Marshall extrusion pressure of the taphole clay.

Jul 23, 2025

By B. Orgilbayar, B. Unursaikhan, S. Sukhbat, Ts. Zagarzusem, D. Baasanjav, L. Jargalsaikhan, E. Otgonjargal, N. Sugir-Erdene, Ts. Soyolmaa

This study has investigated the efficacy of the gravity beneficiation method based on gravitation and centrifugal forces for manganese ore. Powdered samples of manganese ores from the Unagad deposit in Mongolia were analysed for their element and mineralogical composition using ICP-MS and X-ray powder diffraction (XRD). The analysis presented the mineralogical compositions of the ores as hydro goethite, manganese minerals and magnetite, gangue minerals as quartz, albite, orthoclase and microcline of manganese ore. Manganese minerals are white in colour and have micro-veinlet, fine grained-aggregates associated with gangue minerals. The most important manganese minerals are hausmannite, pyrolusite, rhodochrosite, and manganosite. The composite of feed containing 17.31 % Mn and 36.3 % SiO2 was processed in a shaking table. In the experiment, a concentrate assaying 41.37% Mn was obtained from this composite with 65% recovery. In another experiment, f80=0.074 mm particle size ore was used in the MGS concentration test. A concentrate containing 38.34 % Mn with 75.2% recovery was produced in this experiment. The results showed that it is possible to obtain concentrate through gravity processing of manganese ore, which is an economically beneficial process for producing a product of a standard requirement. Keywords: Manganese ore, gravity separator, centrifuge, shaking table 1. Introduction

Jan 1, 2020

By Yuandong Qiao, Erdong Li, Chao Lv, Junjian Ye

The gas-based CO reduction of Panzhihua vanadium titanomagnetite concentrate from 1100°C- 1250°C was investigated in this paper. The reduction degree increased with increasing temperature and increasing reduction time. At a temperature of 1250°C and a reduction time of 20 minutes, the metallisation degree reached 92%. The iron-titanium oxide phase transformation during reduction process was Fe2.75Ti0.25O5→Fe2.5Ti0.5O4→FeTiO3→FeTi2O5 according to the X-ray diffraction analysis. The SEM and map scan by energy spectrum of results of reduced samples at different temperatures indicated that the metallic iron particle size increased gradually as the reduction temperature increased. These results can serve as a reference for the reduction of vanadium titanomagnetite by CO. Keywords: Vanadium titanomagnetite concentrate, CO reduction, phase transformation, reaction mechanism

Jan 1, 2020

By M. A. Mahboob, T. Celik, B. Genc, I. Atif, S. Ali

"Mapping of hydrothermally altered areas, which are usually associated with mineralization, is essential in mineral exploration. In this research, open source reflectance spectroscopy data from the multispectral moderate-resolution Landsat 8 satellite was used to map altered rocks in the Gauteng and Mpumalanga provinces of South Africa. The unique spectral reflectance and absorption characteristics of remotely sensed Landsat data in the visible, near-infrared (NIR), shortwave-infrared (SWIR) and thermal infrared (TIR) regions of the electromagnetic spectrum were used in different digital image processing techniques. The band ratios (red/blue, SWIR 2/NIR, SWIR 1/NIR), spectral band combinations (Kaufmann ratio, Sabins ratio) and principal component analysis (Crosta technique) were applied to efficiently and successfully map hydrothermal alteration minerals. The results showed that the combination of spectral bands and the principal component analysis method is effective in delineating mineral alteration through remotely sensed satellite data. The validation of results by using the published mineral maps of the Council for Geoscience South Africa showed a good relationship with the identified zones of mineralization. The methodology developed in this study is cost-effective and time-saving, and can be applied to inaccessible and/or new areas with limited ground-based knowledge to obtain reliable and up-to-date mineral information.IntroductionMany developing nations depend on exploration and exploitation of mineral resources to sustain their economic growth. Usually, the traditional mineral exploration techniques require enormous finances, prolonged time, and tremendous manpower, particularly in areas that are not easily reachable (Maduaka, 2014). Furthermore, mineral exploration required state-of-the-art techniques and expertise along with geological, geochemical, and geophysical datasets, which may not be easily available or may be lacking where access is problematic (Kaiser et al., 2002; Bemis et al., 2014). Modern remote sensing technology has proved to be one of the highly efficient and robust techniques used for mineral exploration. The use of remote sensing satellite images for geological mapping and mineral exploration usually involves studying the physicochemical properties of rocks and weathering soils, such as mineralogy, landforms, geochemical signatures, and the spatiall distribution of lineaments (Bhattacharya et al., 2012)."

Mar 1, 2019