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By Mwaba CC

Ok Tedi Mining Ltd has been using flotation for the production of copper/gold concentrates from a complex copper sulphide ore for several years. During this period, much effort has been devoted to metall- urgical treatment of the ore. This paper examines some of the mineralogical aspects of the sulphide minerals in the ore using the electron microprobe analyser. Results have revealed the complexity of the copper sulphide minerals and in particular, chalcocite. Analysis of both plant and laboratory flotation products has provided further insight into the effects of mineralogy on the flotation of copper and iron sulphides. A significant observation is that some of the pyrite minerals apparently exhibit natural floatability. The implications of the mineralogical characteristics of the sulphide minerals on the flotation of the ore are also discussed.

Jan 1, 1991

By A. Patri, D. S. Nimaje

Wireless sensor networks and wireless communication systems have become indispensable in underground mines. Wireless sensor networks are being used for better real-time data acquisition from ground monitoring devices, gas sensors, and mining equipment, whereas wireless communication systems are needed for locating and communicating with workers. Conventional methods like wireline communication have proved to be ineffective in the event of mine hazards such as roof falls, fires etc. Before implementation of any wireless system, the variable path loss indices for different workplaces should be determined. This helps in better signal reception and sensor node localization, and also improves the method by which miners carrying the wireless devices are tracked. This paper proposes a novel method for determining the parameters of a suitable radio propagation model, which is illustrated with the results of a practical experiment carried out in an underground coal mine in southern India. The path loss indices, along with other essential parameters for accurate localization, have been determined using the XBee modules and ZigBee protocol at 2.4 GHz frequency.

Jan 1, 2015

By R. E. Dye

Introduction Research concerning all phases of hoisting practice, but more particularly the causes and prevention of hoisting rope deterioration and the improvement of safety dogs 158 for shaft conveyances, has been carried on intensively for the past three years in the Province of Ontario. Prior to the hoisting accident at the Paymaster mine on February 2nd, 1945, there had been no fatalities in the Province due to a hoisting rope failure. It was probably on this account that little original research on hoisting problems had been undertaken here and that the mining industry had been content to look to British, South African, and United States investigators for new developments in this field. Except for the Paymaster accident this might still be the case since, in any industry, it is apparently necessary for a serious accident to occur before any extensive programme of preventive research is launched. When this accident occurred, the Government of Ontario, with the close co-operation of the Paymaster officials and the mining industry as a whole, took immediate steps to determine the cause. A five-man, non-industry committee, selected from the Faculty of the University of Toronto with Dean C. R. Young as Chairman, was appointed by the Government, and a three-man Committee consisting of R. D. Parker, General Superintendent of the International Nickel Company of Canada, Limited, R. L. Healy, General Manager of Wright Hargreaves Mines, Limited, and R. E. Dye, General Manager of Dome Mines, Limited, with the latter acting as Chairman, was appointed by the Ontario Mining Association.

Jan 1, 1948

By Jamie Archibald

The Department of Mining Engineering at Queen?s University conducted a study of backfill practices in underground mines across Canada to assess the current state of backfill usage and to overview potential hazards associated with backfill practice, from preparation to transportation to placement. The primary aim of this study was to cover each component of a typical mine backfill system, and to identify potential incidents leading to the disruption of backfilling operations and any associated corrective actions. This paper, Part II of the study, deals with underground operations consisting of backfill transportation and backfill placement. Part I of the study, which deals with surface operations consisting of backfill material supply and backfill plant preparation, is also presented in these proceedings. A review of safety measures associated with current backfill operations and recommendations for procedures of best practice that should be implemented to reduce fill-related hazards in all mine backfill workplace environments are presented. In general it has been found that system failures normally lead only to minor losses to the operations.

May 1, 2009

By H. Kose

In this research, a model quarry with an annual production capacity of 1 000 000 tonnes has been studied for both pit and hillside quarry cases with constant overall slope angle and variable bench slope angle, considering road grades of 8 per cent and 10 per cent. First, technical requirements have been determined and then the effect of production parameters, such as hole diameter, type of quarrying (pit or hillside) and road grade, on the cost has been investigated to determine bench height. Based on the results, it has been concluded that hole diameter has to be kept large in both pit and hillside quarrying to reduce drilling unit costs. In addition, in order to take advantage of gravity and reduce transportation cost, it has been suggested that bench height and road grade have to be kept high and low respectively in the case of hillside quarrying (downhill transportation) while, in the case of pit quarrying (uphill transportation), bench height and road grade have to be kept low and high respectively, in order to transport the blasted material to a lower height and distance, to save energy, thus decreasing the transport cost. Keywords: Quarry, pit, hillside, road grade, bench height

Jan 1, 2005

By G. A. Bezuidenhout, S. Bradshaw, W. Malan

"The purpose of the study was to investigate the feasibility of SiC reduction of low-grade concentrates from Lonmin’s Rowland and Easterns operations with respect to metal fall and PGM recovery. These concentrates are rich in SiO2 and MgO with low concentrations of chalcopyrite and Cr2O3. Pd is the most abundant of the PGMs. SiC reduction of samples was conducted at 1600? with 2.5-3.5 kg SiC per 100 kg concentrate.PGM recoveries for Easterns concentrate were better than for Rowland. More than 85% of the Ir and Pd and almost 60% of the Pt were recovered with 3.5 kg SiC per 100 kg concentrate. SEM of slag samples showed little entrainment of metallic prills compared to Rowland samples. This was attributed to the relatively higher melt viscosities of the Rowland concentrate. In order to decrease slag viscosity and to enhance PGM recovery, the FeO content of the Easterns concentrate was increased with the addition of 10 kg converter slag per 100 kg concentrate. Ir and Pd recoveries were increased to about 95%, while Pt recovery was around 70%. On the basis of these results an optimum feed ratio between Easterns and Rowland concentrates and converter slag is proposed. Carbothermic reduction of the optimum charge was also compared to SiC reduction. Carbothermic reduction yielded a marginally higher metal fall; however, the calculated gas emissions and energy requirements were higher than for SiC reduction."

Jan 1, 2015

These proceedings consist of papers presented at two Bureau of Mines Technology Transfer Seminars for the purpose of disseminating recent advances in mining technology related to coal mine fire and explosion prevention. Primary, although not exclusive, emphasis is placed on underground coal mining. The papers address research accomplishments ranging from methods for detecting mine fires to remote sealing systems for extinguishing coal mine fires. Each paper represents the current state-of-the-art in the respective research categories. Presentations include research occurring from both Bureau in-house and contract efforts.

Jan 1, 1978

By R. D. Berkenkotter

Titanium and iron assays obtained from cores of three diamond-drill holes from the Cebolla Creek titaniferous iron deposit were evaluated by statistical techniques to obtain information concerning the mineral characteristics of the deposit and to make a preliminary determination of sampling requirements for the deposit. A range of sample volumes representing sizes from one-sixth NX core 2 feet in length through full NX core 10 feet in length were prepared by split-ting the NX core with a diamond saw and combining pulverized splits. Results indicate the existence of at least two statistical populations having different average grades of iron and titanium. Each has an assay frequency distribution that is not normal but is highly peaked (leptokurtic). Frequency distributions of assays from specific altered zones of the drill holes appear to be normally distributed. Increasing the cross-sectional area of the sample unit to change assay volume did not result in significant changes either in assay values or the resulting frequency distributions of assays. However, when assay volume is increased by increasing sample interval, the shape of the assay frequency distribution changes, and a normal distribution of assays is approached. Positive correlation exists between titanium and iron assays. The degree of correlation, although very significant, is too low to use for prediction purposes. Although the amount of data from three widely separated drill holes is not sufficient to establish an average grade for this large deposit, it indicates a range of expected assay values and provides some information for determining requirements of future sampling for evaluation purposes.

Jan 1, 1963

By M. Bwalya, L. Mabokela, L. C. Woollacott

This paper presents a study on the ability of the King stratification modelto describe density stratification patterns that are achieved under idealizedconditions. Tests were conducted in a batch jig using artificial particles inseven density classes. All particles in a density class had essentially thesame density, size, and shape. Tests were conducted for particle systemsinvolving from two to seven components. Good agreement was obtainedbetween measured and modelled data to an extent that gave strongendorsement of the mathematical appropriateness of the core equation inthe King model. Somewhat ambiguous results were found with regard toclaims about the independencies of the single experimentally-determinedparameter required by the model.

Jan 1, 2015

By Yijun Caoa, Xiuxiang Taoc, Zhongbo Hub, Yinfei Liaoa

A new preparation scheme for a difficult-to-float coking coal from the Kailuan Mine, Tangshan, China was investigated. The results showed that grinding followed by column flotation was beneficial for obtaining products with low ash content. The positive effect of grinding on the coal floatability is attributed to the liberation of intergrowths and coal surface improvement. Tests indicated that 10 minutes was the optimum grinding time, and over grinding resulted in a deterioration in flotation performance. With a grinding time of 10 minutes, conventional flotation had potential to yield a product with around 12.42% ash content and 69.15% combustible recovery. Column flotation can reduce the product ash content to 11.15%and increase combustible recovery to 74.47%. Consistently better flotation results reveal that column flotation is more efficient than conventional flotation for such fines.

Jan 1, 2015

By Gerhard Braüner

The present knowledge on ground movements and mining damage is mainly based on observations made when mining seamlike deposits. The studies, rules, and regulations in different countries agree in that the differential ground movements, especially the strain, account for the damage to structures. Accordingly, large buildings are particularly susceptible. The opinions on what amount of ground deformation induces what degree of structural damage are not quite uniform. Mining damage can be reduced or prevented by structural and/or underground precautions. The latter comprise measures for generally reducing the ground movements (leaving pillars, filling, partial extraction) and for reducing temporary movements (rapid extraction, specially arranged workings). Because the differential movements decrease with increasing depth of mining, safety pillars are largely dispensable at greater depths. Shafts are mainly affected by the vertical derivatives of rock displacements, but extraction in the vicinity of shafts is feasible even under difficult conditions. The theoretical concept of the ground movement process established in part 1 of this work is in qualitative agreement with the facts herein observed. As a quantitative approach, it should be applied to calculating ground surface movements rather than rock movements about underground openings. It can be extended by introducing more detailed strata characteristics.

Jan 1, 1973

By M Carter

The Great South Basin is located beneath the northwest part of the Campbell Plateau, a+broad, nearly level, triangular shaped submarine platform, southeast of the South Island of New Zealand. It encompasses an area of 77 700 square kilometres and contains a sequence of Cretaceous to Tertiary sedimentary rocks which are up to 6000 metres thick near the centre of the basin (Shirley, 1983). The western boundary of the basin is adjacent to the steep Aucklands Slope. In the+ north it merges with the Canterbury Basin and to the south onlaps against the Pukaki Rise, a basement high. The eastern margin of the basin is bounded by the northeast - southwest trending steep linear Antipodes Scarp. In the extreme south the Antipodes Scarp curves westward and joins the north trending Aucklands Slope. The Campbell Plateau is dominated by tensional tectonics. The Antipodes Scarp represents a major region of transcurrent faulting initiated by Cretaceous rotation within the Campbell Plateau. Later movements are associated with the Alpine Fault of the South Island (Sandford, 1980; Anderton, Holloway, Engstrom, Ahmad and Chong, 1982).

Jan 1, 1983

Study on Treatment of Wastewater Containing Heavy Metal Ions Using Modified Oceanic Cobalt-Rich Crusts

Sep 13, 2010

By Robert G. Nisle

The classic theory of pressure build-up in shut-in oil wells as developed by Horner and van Everdingen is based on two-dimensional radial symmetry in the well-reservoir system. Such symmetry does not exist in the case of a well which parfiially penetrates the producing formation. As a result of this lack of symmetry the use of the classic theory in such cases become questionable. In this paper the mathematical theory has been extended to include the case of partially penetrating wells. Numerical solutions illustrating the up-dication of the equations are presented. The effect of partial penetration on pressure build-up is shown by a comparison of synthetic pressure build-up curves derived from the numerical solution of the equation for partially penetrating wells for various degrees of penetration. It is shown that partial penetration is detectable from the characteristic shape of the pressure build-up curve and that formation productivity may be calculated from the pressure buildup data in a manner identical to that described by the classic theory. INTRO DUCTION The use of pressure build-up data on shut-in oil wells is a well-established technique for the measurement of reservoir productivity. The work of Homer' and van Everdingen' is well known. Since the publication of their pioneering work, others"' have elaborated and extended the technique. These authors have dealt exclusively with the case of wells that completely penetrate he producing formation. Two-dimensional radial symmetry is achieved, thereby, and the problem is greatly simplified. This ideal situation is seldom encountered in practice. But, in spite of this, the technique is often employed anyway. The question, therefore, arises: how much confidence can be placed in the results of such calculations when the data are taken on wells that only partially penetrate the producing formation? It is the purpose of this work to answer this question. Only the single-phase fluid case will be considered. van Everdigen' has presented a rigorous solution of the two-dimensional case, but because of mathematical complexity, this solution has not proved to be particularly useful. Horner' utilized Kelvin's point source solution in two dimensions and showed that it is a sufficiently good approximation for oil reservoir studies. The geometry of the well and the producing formation is illustrated in Fig. l. Geometrically the formation may be described as an infinite slab. The infinite slab is defined as the solid (the porous medium in this case) bounded by two parallel planes. Thus, the slab extends to very great distances in both the positive and negative directions of two of the coordinate axes, but is finite in

A study of literature on the epidiorite dykes which transgress the Broken Hill lode and its wall rocks reveals a considerable diversity of thought regarding the time of emplacement of such dykes. In this paper it is deduced that the epidiorite dykes were formed at a late stage and were probably post-ore. Detailed mapping, sampling, and correlation of data from over 100 exposures substantiates this deduction. Physical disruption of the epidiorite dykes is indicated and some interaction of the epidiorite and ore at the time of intrusion is inferred.Further petrological study may confirm this.

Jan 1, 1968

By Brian Wilson, Megan Atkinson, Richard Diggle, Nathan Sweeney

"Ruskin Dam, located near Mission, British Columbia, was constructed in 1929 and 1930 and comprises of a concrete gravity dam structure founded on bedrock. At the right abutment, which consists mostly of dense to very dense sands and silt, the dam abuts against overburden soils, and connects to a cutoff wall system consisting of sloping concrete slabs. Significant seepage and piping issues were encountered during first filling of the reservoir in 1930. In 2012, BC Hydro, the owner of the dam, awarded a contract for the construction of seepage control measures at the right abutment, including construction of a plastic concrete cut-off wall extending upstream of the dam, a plastic concrete seepage training wall extending downstream of the dam, tie-in of the new cutoff wall to the dam, consisting of jet grouting of the soils adjacent to the dam to allow for the construction of the special cutoff connecting the cutoff wall to the dam, and construction of additional jet-grouting ground improvement downstream of the dam.Integral to the upgrade was the requirement for the special tie-in cutoff wall, consisting of a highly flexible, impermeable membrane to connect the concrete dam to the new, 1 m thick plastic concrete cutoff wall. The tie-in extends vertically into bedrock through the dam and jet grout columns constructed adjacent and beneath the overhanging portion of the dam at the right abutment. The membrane is required to survive the anticipated earthquake induced deformation between the dam and the abutment soils.This paper describes the processes used to develop a material suitable to meet the specified flexibility and permeability criteria, as well as the innovative construction techniques utilized to construct the slot and place the bituminous material within it. The final dimensions of the slot were in the order of 7 m long by 25 m deep by 0.17 m wide. The bituminous material was placed under a head of water which was required to maintain stability of the slot, and was placed at temperatures in excess of 120 degrees Celsius."

Jan 1, 2017

By J Lööw, M Nygren, E Segerstedt, L Abrahamsson

The purpose of the paper is to discuss socially sustainable development in the mining industry and the communities surrounding the mines. The discussions are based on results from a prestudy and literature review on mining and sustainable development conducted during 2013–2014 at Luleå University of Technology in Sweden. ‘A social licence to mine’ is important for the mining industry, but the social dimension is a relatively underdeveloped dimension when it comes to sustainable development in general and the mining industry in particular, one reason probably being the lack of effective methods for capturing social impacts. The mining industry and the surrounding communities face many challenges that provide both possibilities and obstacles to socially sustainable development; eg aspects such as gender, work conditions and cultural aspects. For example, a strong mining workplace culture and community identity can create strong cohesion but also lead to excluding certain groups, rejecting new ideas and reinforcing obsolete values. Other challenges include recruitment, as well as health and safety in relation to an increased use of fly-in-fly-out, contractors and automation of mining. Some challenges relate to the effects of fluctuations in the mining market. There is a lack of research that links attitudes, policies and activities within companies to their impact on the wider community, and vice versa. Future research should also include the development of methods and indicators for social sustainability relevant for mining – in other words: how do mining companies get ‘a social licence to mine’?CITATION:Abrahamsson, L, Lööw, J, Nygren, M and Segerstedt, E, 2015. How to get a social licence to mine, in Proceedings Third International Future Mining Conference, pp 125–136 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 4, 2015

By Dale Berner, Michael O’Sullivan

"This paper focuses on lessons learned from the innovative designs, in-the-wet construction methodology and modified foundation conditions, for two United States Army Corps of Engineers, USACE, Megaprojects:(a) The over $2 Billion Olmsted Dam across the Ohio River for the Louisville District; and(b) The $1.75 Billion Inner Harbor Navigation Canal, IHNC, Lake Borgne Hurricane Barrier in New Orleans for the Hurricane Protection Office, and the New Orleans District.Design innovations for the 24-inch dia. pipe pile foundation for the Olmsted Dam project include: (i) the use of controlled-fixity moment connections to the dam monoliths in order to tune the response of the dam under the 8.3 Richter scale seismic Maximum Credible Event, MCE; (ii) soil densification to inhibit liquefaction potential and (iii) design to facilitate underwater construction in a river with a highly moveable sand bed.Design innovations for 66-inch dia. concrete cylinder piles for the IHNC floodwall include: (i) the use of soil structure interaction, SSI, analyses to verify capacity to resist deep-seated failure plane in soft soil, while limiting lateral deflections to acceptable limits; (ii) the use of geo-fabric and scour stone for enhanced foundation response and (iii) design for ""in-the-wet"" construction on a fast-track basis.LESSONS LEARNED FROM THE INNOVATIVE OLMSTED DAM FOUNDATIONThe over $2Billion Olmsted Dam on the Ohio River is currently under construction 16 miles upstream from the confluence with the Mississippi River. It will consist of an 800-foot-long tainter gate section, a 1,400-foot navigable pass, two boat abutment sections, a fixed weir section, and upstream and downstream scour protection. The Olmsted Dam and its two, 1,200-foot locks, which were built in 2002, will eventually replace both Locks and Dam #52 and #53, both built in 1929, and thereby bring significant benefits to the Ohio River navigation system.In 2002, the Jacobs/COWI JV completed the design of the dam; which was an engineering challenge for several reasons, including:(a) Its proximity to the New Madrid Fault, could impose an 8.4 Richter Scale seismic event on the structure, which is located in an area of potentially liquefiable alluvium. The extensive seismic analysis performed by COWI included a response spectra analyses; lateral pushover analyses of pile foundations; hydrodynamic added masses; pile group effects; and the development of kinematic motions as a result of the soil-pile-structure interaction.(b) Maintaining vessel traffic along the river and accommodating fluctuating river elevations between 30-40 ft annually, and as much as 60 ft in a 100-year period.(c) Designing for the scour and uplift forces of artesian ground water and preserving a wildlife sanctuary on the Southern shore at the dam site."

Jan 1, 2017

By D Craw, L Cox, R J. Norris

The Rise and Shine Shear Zone is a mineralised low-angle deformation zone traceable for at least 7 km through biotite zone schist of the Dunstan Range, central Otago. The zone is commonly believed to be similar to the actively mined Macraes deposit. The Rise and Shine Shear Zone occurs in the immediate footwall of the Thomsons Gorge Fault, a regional scale Cretaceous normal fault that juxtaposes chlorite zone schist against biotite zone schist. Most mineralised rocks are deformed and record a progression from early stages of semiductile deformation to more brittle cataclasis. Folds in mineralised rocks trend northwards. The mineralised schist is hydrothermally altered with variable silicification, sericitisation, chloritisation, replacement of titanite by rutile and carbonate alteration. Gold is associated with pyrite and arsenopyrite and occurs in both ductile and brittle microstructures. Sheared and mineralised schist is cut by north-striking fault zones which host mineralised quartz veins. Veins in the shear zone contain hydrothermal albite. Trace element analyses show enrichment in As, U, Th and rare earth elements. Many of the above features are similar to Macraes deposit, but there are important differences. In particular, the Macraes deposit is hosted in lower grade rocks and truncated beneath by a normal fault, Macraes has no U or Th enrichment, Macraes veins have no albite and folds at Macraes trend NW-W. Rise and Shine mineralised rocks have no Cr enrichment and no hydrothermal graphite.

Jan 1, 2005

By N. E. Yasitli

There is a considerable amount of lignite reserve in the form of thick seams in Turkey. It is rather complicated to predict the characteristics of strata response to mining operation in thick seams. However, a comprehensive evaluation of ground behaviour is a prerequisite for maintaining an efficient production, especially when top coal winning by means of caving behind the face is applied. A comprehensive modelling of deformations and induced stresses is vital for the selection of optimum production strategy. In this study, numerical modelling and analysis of a longwall panel at Omerler underground coalmine have been carried out by using the software called FLAC3D developed based on the finite difference technique. Firstly, a 3-D numerical model of the M3 panel has been prepared. Secondly, induced stresses formed around the longwall face have been determined as a function of face advance where the face was located at the bottom of thick coal-seam. Results obtained from modelling studies have revealed that the front abutment vertical stress was maximum at 7 metres in front of the face and magnitude of front abutment stress was found to increase up to a distance of 200 metres away from the face start line. As the face was further advanced after 200 m from the face start line, there was not any significant change in the characteristics of front abutment stresses. Results of numerical analysis of the panel were in good agreement with in situ observations.

Jan 1, 2005