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By Cem Şensöğüt, Özer Ören, Yaşar Kasap

The mining sector, which has an important place in terms of raw material and energy supply, is referred as a sector with one of the highest fatal accidents in comparison with other sectors. In this century, where occupational health and safety awareness has increased, it is important to review the past accident statistics and to determine the current deficiencies by using the information in the inventory. In this study, the Malmquist total factor productivity index (MPI) has been utilized to investigate the changes in the work accidents occurring in the Western Lignite Corporation (Turkey), where underground and surface production methods are applied, and to determine the measures to be taken. According to the results obtained, both the decrease in production amount and the increase in the number of accidents caused inefficiencies during the period in concern due to the expected 10-year economic life of the mechanized system operating in the underground production panel that came to an end in 2007 and the flooding took place in early 2017. Compared with the underground operations, it has been determined that production can be carried out at the appropriate scale despite the heavy working conditions encountered due to the changing climatic conditions and the progress of production in the surface operations.

By Z. T. Mathe, M. A. Vera, M. C. Harris

This contribution presents a methodology how to quantify froth zone recovery in a continuously operated laboratory mechanical flotation cell. The methodology consists of relating the overall flotation rate constant to the froth depth of the flotation cell. As a result, a froth zone recovery factor (Rf) can be extracted. This froth performance parameter has been studied as a function of the flotation cell operating variables. By understanding the effect of these operating variables on Rf, an integrated methodology for modelling froth zone performance in batch and continuously operated laboratory flotation cells has been proposed. The Rf modelling is based on a semi-empirical approach which considers a number of parameters to be used. Some of these parameters may have physical significance, i. e. they may be easily and physically measured. The modelling approach consists of taking into account the interaction between the pulp and froth zones. This interaction allows froth zone recovery (Rf) to be predicted. The whole modelling exercise process lies on auxiliaries relationships which indicate the dependence of the parameters with the operating conditions of the flotation cell. This contribution is part of a larger project that deals with the modelling and optimisation of flotation plants (Project P9L, 2000).

Jan 1, 2001

By Yunsheng Yao, P. Golledge, A. D. S. Gillies

In order to investigate the explosibility of sulphide mineral dusts, sulphide ore samples were collected from five underground metalliferous mines in Australia. The mineralogical and chemical composition of the dust samples was analysed by X-Ray Powder Diffraction and Atomic Absorption techniques. Simulated post detonation fumes were produced and used in dust explosibility tests to examine the influence of the fumes on sulphide dust ex- plosions. These tests were conducted in a 20 Litre Siwek Explosion Chamber with measurement and control system that is regarded as a standard testing system worldwide for dust explosion studies. The dust mineralogical composition and dust explosibility tests indicated that the content of sulphur can not accurately predict the explosibity of the sulphide dust. The percentage content of pyrite in the sulphide dust can be a relatively reliable diagnostic criterion in evaluating the risk of sulphide dust explosions in the mining of a massive sulphide orebody. The hybrid explosion tests demonstrated that the post detonation fumes from ANFO not only decrease the lower explosion limit of the sulphide dusts, but also increase the severity of the dust explosions. The explosion pressure reaches its peak value when the fumes content in the explosion chamber is about 20 per cent by volume

Jan 1, 1997

By P. Diehl

The increasing public interest in a useful framework for an assessment and classification of mineral resources (1) is documented by the recently published international classification scheme of the United Nations (1979) and the revision of the classification system of USBM/USGS (2) (1980). Moreover, various classification systems are currently discussed by the mining industry. In spite of major improvements in respect of the concepts, definitions, and taxonomy of ore classification, it has been recognized that the recent practice to classify mineral resources does not create truly reproductible results, i.e. an assessment to the various categories which is free from personal bias or corporate interests. Following are geostatistical methods proposed for a standardization and quantification of various terms in ore classification. After critical review of present practices, we will establish a precise link between the classical terms such as "measured", "indicated", and "inferred" reserves and the geostatistical concept of estimation errors. Moreover, we will demonstrate, how the basic criteria of economic feasibility, geologic assurance and recovery can be taken into account by geostatistics. A specific algorithm will be proposed to block out and to classify reserves according to the degree of geologic assurance. . We will also show computerized methods which perform complete classification procedures, and will also exemplify them with typical case studies.

Jan 1, 1982

By Terry Owen

Business development process. Throughout Cyprus Amax's early months in Russia, the company stayed focused on what was needed from a deposit for economic success. Cyprus Amax's reason for success in Russia is that all involved - its Russian partners, the workforce and expatriates - provided a focused effort that served the project as it worked through the tender process and the Russian regulations. The company developed an understanding of the regulatory process by working with solid, ethical partners. Infused into the Kubaka management structure were Russians with the knowledge to facilitate the process and a professional group of expatriates. Developing credibility and a solid rapport with the Russian mining authority was critical to the success of this venture. Identifying and gaining the trust of key Russian individuals was also critical during the early stages. Gaining their trust and building credibility was part of the process. These key Russians were brought to the United States to visit existing Cyprus Amax mines. These efforts proved valuable in building an understanding with the Russians about the kind of company Cyprus Amax is and the kind of efficient operations that it can run. This was a learning process for all parties. Fortunately, the company was dealing with intelligent and educated people.

Jan 1, 1997

By Zsolt Csillag, Dragorad Ivankovic, Miomir Ceh, Anna Csordás-Tóth

Results of the common research work of ALUTERV-FKI and RI in field of ore dressing are presented here. Although monohydrate types of bauxites consist of finely dispersed minerals, however, in some cases certain contaminants (carbonates mainly), can be reduced by physical methods before Bayer process. Electronmicroscopy combined with computerized data processing is proven to determine the possibility of beneficiation and to control the different stages of ore dressing. Test results gained by Hungarian and Yougoslavian bauxite samples, contaminated by calcite, dolomite, siderite and pyrite, are discussed. Basic operations were: grinding (mostly dry) and classification, magnetic separation (mostly wet) and selective agglomeration. Only simple processes, having high efficiency and mostly dry ore dressing technique may meet the requirement of economical criteria. 1. [CONDITIONS OF ADAPTING THE BAUXITE DRESSING METHOD] Bauxite is a relatively cheap raw material, occurring in great bulks. Bauxite deposits may often lay far from the traditional ore processing plants, and in such cases the ore reaches the plants after long transportation. Some of these plants must face the difficulty that the resources of high quality ore are exhausted, they fall short of supply and, consequently, they must decide on whether to utilize the existing resources of poorer

Jan 1, 1984

By J de Cuyper, N. R. Tipman, G. E. Agar, L. Laré, W. Freyberger

The flotation chemistry of the commercial INCO matte separation process was investigated. The slow cooling of Bessemer converter matte forms discrete phases of Cu2S and Ni3S2 and a Cu-Ni alloy. After magnetically removing the alloy, the Cu2S and Ni3S2 are separated by flotation at pH 12.4 (saturated lime) using diphenyl guanidine (DPG) as both collector and frother. DPG has been used exclusively in this flotation process because of its unusual selectivity for copper minerals. The surface product resulting from chemisorption of DPG onto the Cu2S was identified as the double salt Cu(DPG)2SO4,.CU(DPG)2(OH)2. The adsorption followed Langmuir behaviour up to a monolayer coverage. In the absence of DPG, the rapid adsorption of oxygen by Cu2S in flotation pulps was observed. The surface product was identified as the insoluble basic copper sulfate CuSO4.3Cu(OH)2 with the production of sulfate ion. In the presence of DPG, the oxidation reaction appears to be suppressed. The frothing properties of DPG and commercial frothers were compared. DPG is not a powerful frother. Batch flotation tests confirmed that DPG is a highly selective collector when compared to most sulfhydryl collectors.

Jan 1, 1976

By P. M. Soupios

An integrated suite of environmental methods was used to characterize the hydrogeological, geological and tectonic regimes of the study area, to determine the geometry of the landfill (depth and spatial extent of electrically conductive anomalies), to define the anisotropy caused by bedrock fabric fractures and to locate potential zones of electrically conductive contamination. The study area which covers an area of about 0.08 Km2 is a municipal solid waste site (MSW), located 20Km West of Herakleion in the central part of Crete (S. Greece). The landfill is located in a northwest oriented valley with highlands to the northeast and southwest. The combination of geophysical methods and chemical analysis are commonly implemented for characterization and management of land-fills. At the particular site, geophysical methods were focused on studying the electrical insolating properties of the materials, electrical con-ducting properties of fluids (leachates) and electromagnetic properties of the disturbed regolith materials in the burial zones. Three different types of geophysical surveys were performed: 1) 2D electrical tomography (ERT), 2) electro-magnetic measurements using very low frequencies (VLF) and 3) electromagnetic conductivity (EM31). Furthermore, in order to calibrate the geophysical methods dielectric spectrometry measurements are conducted. To evaluate the environmental degradation of the area, soil and liquids samples were collected.

Jan 1, 2005

By Ron Parks

High Pressure Grinding Rolls (HPGR) was introduced to the mineral processing industries in the mid-SO's as a tool for comminuting raw and processed materials. This tool made its an impact in the Cement Industry where it was used as a pre-grinder on existing ball mills, raw and finish grinding in a mill circuit and other various applications. This concept was a big success where the cost of power was high along with the desire to increase capacity. The HPGR reduced the power requirement and increased the capacity in the ball mill due to the finished product produced by the HPGR and the micro fractures in the coarse rock, which reduces the power required to finish grind the rock. This unit has found acceptance in many other industries including diamonds, iron and other selective applications. The diamond industry uses this tool for selective grinding purposes since the kimberlite rock is considerably softer than the actual diamonds. Therefore within a bed of material, kimberlite is crushed to fines and the diamonds are liberated and unharmed. The iron industry primarily uses this tool for concentrate comminution; however, there are installations using this tool as a pebble crusher and in an AG-pebble mill circuit.

Jan 1, 2000

By E. K. Albert

Title IV of the 1977 Surface Mining Control and Reclamation Act (SMCRA) provides for an abandoned mine reclamation fund. This fund, taken from fees collected from operating coal mines, provides capital for the reclamation process. The Act directs the Office of Surface Mining (OSM) to collect the fees based on coal production. Monies from the abandoned mine lands (AML) fund are distributed through two programs. The first provides OSM with capital to use in emergency situations resulting from abandoned mine sites and reclaiming high priority sites in states without established AML programs. The second distributes the money through a state's AML program in the form of grants. To provide for a flexible and customized selection procedure for AML projects, a management information system (MIS) that combines scientific selection procedures is being developed. This system employs objective and subjective methods developed in systems research in recent years. The MIS component is an essential part of any selection process involving large numbers of potential projects. It must contain all the necessary project parameters that can be applied to the selection of projects whether or not they are to be used in the immediate selection criteria. In addition, variable selection criteria will allow ‘what if’ types of inquiries for comparison of differing selections and benefits.

Jan 1, 1990

By Martin F. Grier, Nicholas H. Kempton

The Mt. Todd Gold Project in the Northern Territory is a joint venture between Billiton Australia Gold Pty. Limited, a wholly owned subsidiary of Shell Australia Limited, and Zapopan NL. As manager of the project, Billiton is guided by Shell's corporate policy that foremost consideration be given to protection of the environment from unacceptable impact and that sound environmental programmes are to be implemented effectively at all company operations. This policy on Health, Safety and the Environment helps operating companies in addressing environmental matters in a systematic way and gives guidance on the practical implementation of a range of controls to protect the environment. Most importantly, it seeks to do this in a co­ operative rather than adversarial manner. In developing the Mt. Todd Gold mine the joint venturers' environmental objectives have therefore been to plan and operate the project consistent with the highest industry standards and community expectations and in accordance with all Northern Territory government requirements. A development strategy has been designed which minimises environmental effects. Planning priorities have focused on the successful co-existence of the mine with an endangered species of bird, the Gouldian Finch, which breeds in the area; the mitigation of impacts on surface and ground. water qualities; and the protection of significant Aboriginal cultural and archaeological sites.

Jan 1, 1991

By A. Goulsbra, S. McAllister, R. Dunne

Since 1992, a tailings gravity re-treatment plant has been in operation at the New Celebration Gold Mine to recover aurifer­ous pyrite (Martins, Dunne and Gelfi 1991; Martins, Dunne and Delahey 1993). The gravity pyrite concentrate is ground in a Tower mill to liberate gold (average particle size around 25µm) prior to cyanide leaching. Although the re-treatment plant has met the predicted gold recovery, based on original laborat01y testwork, there is still room for improved gold recovery. This requires enhanced pyrite recovery, especially in the finer size ranges. The application of centrifugal gravity separators would seem to be an ideal means to achieve this criterion. In particular, the Falcon continuous centrifugal separator (Series C machines) would appear to be ideal for this particular duty. A testwork program to evaluate the application of the contin­uous Falcon to recover pyrite from New Celebration ores was unde1iaken over a six month period during the later part of 1997. The work involved laboratory batch testwork, followed by con­tinuous testing of the Falcon Cl0 (2tph to 3tph) and Falcon C40 (l00tph) units. A summary of the results from this evaluation program are provided in this paper.

Jan 1, 1998

By G. A. Hayes

The range of gold ores tested at AMMTEC LTD over several years has resulted in the requirement to analyse for the mode of occurrence of gold in order to assist selection of ore processing options. The aim of this paper is to describe the laboratory testwork and analytical procedures which have been of benefit in detail­ing the mode of occurrence and mineral associations of gold and hence being of value in developing an optimised ore processing route. The range of ore and mineral assemblages described include relatively simple pyrite and free milling ores, more complex pyrite plus arsenopyrite gold ores and the quite com­plex associations of gold in copper bearing ores or with car­bonaceous mixed sulphide ore assemblages. The aim of this paper is to describe the laboratory testwork and analytical procedures which have been of benefit in detail­ing the mode of occurrence and mineral associations of gold and hence being of value in developing an optimised ore processing route. The range of ore and mineral assemblages described include relatively simple pyrite and free milling ores, more complex pyrite plus arsenopyrite gold ores and the quite com­plex associations of gold in copper bearing ores or with car­bonaceous mixed sulphide ore assemblages.

Jan 1, 1996

By Marlin D. Schutte, Graham M. Fraser, Paul M. Kubera, Ronald J. Weetman

Mixers play an important function in the operation of multi-phase reactors in the minerals processing industry. They must suspend solids, transfer oxygen, maintain pH and temperature uniformity, assist in heat transfer, and, in biological processes, avoid the development of excessive shear rates. The LIGHTNIN A315 impeller (Figure 1) effectively supersedes the older Rushton turbine (Figure 2) which has been classically employed in gas­Iiquid-solids applications such as bacterial oxidation, cyanide destruction, etc. Since a stirred tank reactor can be such a key part of the overall process, it is essential that the mixers be designed for long term reliable operation, both process and mechanical, to insure a high percentage of on-line availability. Mixers in gas-liquid-solids processes may experience extraordinary loading conditions which must be taken into account to guarantee a robust mechanical design. Given the recent trend towards the design of world-class process units with maximum capacity equipment, there is increased importance and emphasis on the integrated design of the complete agitation system -mixer, vessel, and structure -to insure trouble free, post­commissioning performance. This paper presents some of the considerations necessary to specify the process functions of the mixer in multiphase applications, as well as special considerations for the mechanical design of the integrated reactor system.

Jan 1, 1993

By P. Tsakiris

The increasing social interest for the environmental issues, forces the authorities to enact more rigorous regulations. The mining industry is one of the sectors that concentrate vigorous remonstrance. It is an absolutely justified reaction, as a result of the numerous contaminated and polluted sites that have been inherited by previous operations and they remain unremedied. The lack of a consolidated global legislation, transfers the burden of decisions to the national level. This paper consists of two parts. At the first part, it discusses the critical role of the state to form an effective environmental policy, feasible for the context of the national economy. Afterwards it analyses two of the main points, which must be considered by the regulator for the excavation activity, the abandoned sites and the duration of the mining investment. The aims are to defuse, in the short-term, the public pressure, protecting the economic growth and, at the same time, to form a basic structure for the development of the corporate social responsibility. The second part presents an alternative financial instrument for the Greek regulatory framework, conformed to the characteristics of the Greek Economy, and analyses the expected benefits both for the business and the social welfare.

Jan 1, 2002

By N. S. Tombs

This paper presents the experimental results of an ongoing investigation into various properties related to the performance and durability of concretes made using existing and new cement replacements. The process of cement and concrete production is investigated focusing on product performance and environmental performance. The overriding factor for the progression of a material will be product performance however; each material selected will have many intrinsic environmental benefits. The study combines Ordinary Portland Cement (OPC) with each cement replacement candidate using the most common replacement percentages, 10, 20, 25, 30 and 50 percent. A 35N/mm2 concrete is then prepared and analysed in the fresh and hardened state. In addition, a chemical and physical analysis of each replacement material has been performed and results compared to the control samples containing OPC only and Ground Granulated Blast Furnace Slag (GGBS) as a replacement. The results show that in their present form the replacements used in this research do not compare with the strengths achieved by the controls. The right balance of chemical composition and particle grading needs to be achieved to produce a realistic replacement material. The processes required to achieve this must strike a balance between monetary and environmental cost.

Jan 1, 2006

By Robert S. Neil, O&apos

The basic transportation planning process consists of: 1. Inventories and analyses of existing conditions. 2. Estimates of future growth. 3. Determination of future travel demand. 4. Testing alternative systems to satisfy future travel demand. The many modeling techniques used in the transportation planning process are well known, commonly accepted, and thoroughly described in readily available literature. This paper will concentrate on the fourth step of the planning process, specifically the development of alternative systems for testing, and will discuss some of the factors which should be considered during the development of alternative systems. There are many factors which require consideration and which have a bearing on the configuration of alternative test systems. These comments will be limited to the influence of geographic, demographic, geologic, and economic factors. Although addressed separately, the four are to a great extent related and have a significant effect on each other. The objective of examining these factors during the early phases of system planning is to assure that more detailed corridor studies will not be stymied by considerations which could have been anticipated and accommodated at an earlier time. It is particularly important that feasibility of construction be assured before test systems lead to corridor decisions and accompanying commitments to

Jan 1, 1974

By Samantha Smith

Nautilus is completing the world's first environmental impact assessment (EIA) of seafloor mineral extraction and Nautilus has gained extensive experience conducting environmental studies in subsea environments. Nautilus is currently working on the Solwara 1 Project in the Bismarck Sea, Papua New Guinea, where high grade seafloor massive sulfide deposits lie at ~1600 m water depth. Conducting an EIA in the deep sea presents some interesting and exciting challenges. Seafloor studies commenced in December 2005 using a remotely operated vehicle (ROV) fitted out with highly specialized scientific equipment to conduct water quality, sediment, biological and oceanographic studies. During 2007 and 2008, Nautilus launched two two 30-day ROV programs dedicated to environmental baseline studies and during this campaign, over 550 biological, sediment and water samples were collected and over 20,000 seafloor observations were logged. On board specialists included an international team of experts in the field of deep sea marine science. Collaboration between industry and scientific research institutions allows data to be collected for the EIA but also provides an extraordinary opportunity for researchers to access sites that might otherwise remain unobtainable to science. This presentation will review the studies conducted as part of this exciting project. Keywords: Seafloor Massive Sulfides, Environmental Impact Assessment

Jan 1, 2008

By Jaye Pickarts, Bret Boster, Jack McPartland

Pegasus Minera de Chile, Ltda. is completing three phases of metallurgical evaluation on the Pullalli project to develop a preliminary process flowsheet. A project feasibility study is in progress. The feasibility study includes a proposed process flowsheet designed based on results from the multiple stages of metallurgical evaluation. Phases I and II of metallurgical evaluation included laboratory scale heap leach and milling cyanidation testwork on multiple drill core composites and bulk ore samples from the Pullalli Project. Phase Ill included pilot scale milling/cyanidation testwork on Pullalli drill core composites. The proposed flowsheet includes selective mining and separate processing of low grade and high grade ores. Low grade ore will be crushed and heap leached. High grade ore will be milled leached for 12 hours in an agitated cyanidation circuit. After 12 hours of leaching, sands and slimes will be separated and the sands will be washed using a counter current cyclone (CCC) circuit. Partially leached and washed sands will be added to the crushed low grade ore for heap leaching treatment and permanent placement. Partially leached slimes will be thickened in a high capacity thickener and will be processed in a CIP circuit. Leached slimes will be placed in a tailings impoundment.

Jan 1, 1996

By James A. Jones

The Doe Run Co. emerged from the depressed lead market of the mid-1980s as North America's leading lead producer. Doe Run was lean and mean but quickly recognized that technology had advanced while the company was held to the belt tightening slump. With the 1990s approaching, Doe Run moved quickly to update its technology and control equipment to ensure its position as an industry leader. Doe Run was formed in 1986 when Fluor Corp. and Homestake Mining Co. combined their lead-zinc-copper assets in Missouri to form a joint venture. Doe Run is now owned by Fluor Corp. A rich history of mining, milling and smelting started in Missouri in 1862 when the St. Joseph Lead Co. was founded. Subsequent acquisitions led to the formation of St. Joe Minerals, which was later purchased by Fluor Corp. Six mines, four concentrators and two smelters are presently being operated, and a secondary lead smelter was recently commissioned. The Viburnum, Buick and Fletcher operations are lead, zinc and copper flotation concentrators, while the Brushy Creek plant is set up to process high copper-low lead ores. This article looks primarily at the process control installation at the Fletcher concentrator.

Jan 1, 1991