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The reduction in the number and duration of machinery and equipment failures is an important source of economical efficiency enhancement in the Polish coal mining industry.Non-dismantling methods have been thus developed to evaluate the technical state of machines. Among these viroacoustical methods are the most effectively employed. Two-directional organisation of the testing can be chosen, such as periodical and continuous inspection. The monitoring methods for ball bearing, rope tension uniformity, longwall shearers, main fans and shafts installations etc. Instrumentation for monitoring measurements are either of intrinsically - safe or explosion - proof construction, which enables using them in a gas-hazard atmosphere. The development of these procedures has led to the trials to insert the diagnostic methods into the organisational scheme of a coal mine.

Jan 1, 1991

The preamble to the mining Act sets out that such Act is to provide for the encouragement and regulation of mining within the State of Queensland. This paper will attempt to follow the legislative path of such aim and in particular to show what part Mining Wardens play in the administration of the Mining Act.The Mining Act empowers the Governor in Council to constitute Mining Districts and Mining Fields and to appoint any duly qualified officer of the Public Service of Queensland to be a Warden or a Mining Registrar. As a matter of practice Stipendiary Magistrates who hold office in the major centre within a Mining District are appointed Wardens and Clerks of the Court are appointed Mining Registrars. In some districts where there is no Stipendiary Magistrate the Clerk of the Court is appointed an Acting Warden with all the powers of a Warden. Every Warden so appointed is a Warden for the whole State.To achieve impartiality Section 74 of the Mining Act provides that a Warden shall not hold or be entitled (directly or indirectly) to the benefits of any share or interest in a mining tenement or mining venture and provides a penalty of $1000 or imprisonment for six months or both, for contravention of such section.

Jan 1, 1986

By P J. Marsh, P J. Bartsch, N J. Semler

Iron Road Limited is currently studying the feasibility of producing 20 Mt/a of high-grade (67 per cent Fe) magnetite concentrate from a 2.6 Bt resource (JORC) located at Warramboo on the central Eyre Peninsula in South Australia. Bulk concentrate has been tested at a relatively coarse grind size of -106 ¦m. The preliminary flow sheet has been confirmed based on initial mine plans and comprehensive metallurgical testing across the range of mineralisation. Extensive Davis tube testing to predict magnetite recoveries has been conducted over the resource, however this was completed at settings different to the optimised settings developed in the metallurgical test work program.This paper outlines the development of an ore treatment simulation in SysCAD which utilises the mine production plan, the Davis tube test data from the resource, data from metallurgical test work and process design criteria to predict magnetite concentrate deliveries. Mineralogical data, including QEMScan results and metallurgical assessments, were a fundamental basis of the process models which enable predictions of concentrate yield and quality. Power and water requirements are also calculated within the model. SysCAD dynamic simulation has been used to assist with the design of the process plant and downstream infrastructure. The simulation has been set-up to allow iterative integration and optimisation of the mine plan when it becomes available.CITATION:Semler, N J, Marsh, P J and Bartsch, P J, 2013. Iron RoadÆs prediction of magnetite concentrate production from the Central Eyre Iron Project, in Proceedings Iron Ore 2013 , pp 539-546 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Brown N. R

This paper attempts to highlight some of the problems encountered in the economic exploitation of the deeper coal seams by opencast mining methods. The major cost elements of three methods of overburden removal are examined in relation to the overall cost of winning coal from deeper-lying coal seams. The three overburden removal methods examined are dragline stripping and two systems combining dragline stripping with shovels and trucks at varying depths of overburden. A dragline is, undoubtedly, the most cost effective system of overburden removal for depths of up to 30 metres but it is suggested that, when dealing with incremental overburden depths in excess of 30 metres, engineers should consider carefully the possibility of using a shovel and truck operation, or other system, to augment the use of a dragline.

Jan 1, 1986

By S Lakemond, L I. Ku, J Vaughan

Conventional processing of poly-metallic gold containing flotation concentrates are challenging for a number of reasons. One reason is that substantial copper and zinc in the cyanide leach solution compete with gold and silver for carbon adsorption sites. In this study, metal-cyanide adsorption kinetics and equilibrium are measured on three samples of coconut derived activated carbon and one sample of synthetic carbon. Loading selectivity was confirmed to be in the order gold>silver>copper>zinc for all carbon samples. The synthetic carbon tested showed promising results in terms of loading kinetics and capacity for precious metals.CITATION:Lakemond, S, Ku, L I and Vaughan, J, 2013. Effect of carbon type on adsorption of Cu, Zn, Ag and Au from mixed cyanide solution, in Proceedings World Gold 2013 , pp 411-418 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Short KC

The Hunter Region, with a major part of the coal resources of New South Wales and a long history of coal mining, has experienced a rapid expansion of coal resource development in recent years. While there are inevitable conflicts between mining, urban development and related infrastructure, and between mining and other resources, the application of sound planning practices, and improved co-operation and co-ordination among the various parties, helps to reduce such conflicts. The planning process involves consideration of factors such as transport- ation (including port facilities), mine subsidence, provision for surface facilities, a,iC the need for buffer 'ones. In addition, provision must be made for urban expansion, often co-existing or in close proximity to present or future coal mining development. Approval of coal mining developments takes place within the legislative framework of the Environmental Planning and Assessment Act, 1979 (EPA Act), the Coal Mining Act, 1973 (CM Act) and the Mining Act, 1973. Considerable effort has gone into stream- lining and co-ordinating the procedures under these Acts. The EPA Act provides for regional and local environmental plans, as well as a linked process of development control and environmental impact assessment. The CM Act provides for the grant of exploration and coal mining titles and mechanisms for the responsible management of Mining.

Jan 1, 1987

By J Rubio

This work presents design features of an innovative in-line mixing helical (coiled) reactor for flocculation and flotation as a solid-liquid separation process for suspended particles (including liquid droplets). The device has been named flocs generator reactor (FGR), a compact system whereby the flocculation of particles is assisted by the kinetic energy transfer from the hydraulic flow through the reactor and/or by the injection of microbubbles (30 - 70 ¦m). The flow mixing presented a plug flow regime with a low dispersion degree, promoting the required hydrodynamic conditions to disperse the polymer flocculant (cationic polyacrylamide) and to generate æstrongÆ flocs of Fe(OH)3 or clays (as colloidal model systems) with aggregation using an anionic polymer, Al2(SO4)3 and poly aluminium chloride (PAC), and oil emulsions destabilisation with a high molecular weight cationic polymer. The solid-liquid separation of the flocs was then achieved either by settling or by flotation with microbubbles. This paper discusses advances in this new in-line flocculation-rapid flotation device to remove æaerated aggregatesÆ, aggregates with entrained and entrapped bubbles. Studies were carried out with different models of FGRs (varying the length:volume ratio) and process efficiency (mainly kinetics) evaluated as a function of polymer concentration and some operating parameters, namely, feed flow-rate, air:solids ratio and residence time. Results showed that the aerated flocs are readily floated with rising rates in the order of 120 mh-1, values higher than those obtained for the settling of the non-aerated flocs (18 - 24 mh-1). The FGR requires short residence times and generates dense, well structured flocs (with a mass fractal dimension, dF of about three) which withstand high shear forces. Mechanisms involved appear to include small bubble formation and their rapid occlusion (entrapment) within flocs, nucleation of bubbles at floc/water interfaces, polymer coiling as a result of æsalting outÆ effects at the aqueous/air interface and plug flow type of mixing (flocculation). Successful examples of emulsified oil and solids removal from water are shown and because in all cases high efficiencies were obtained (>90 per cent removal). Due to the high process efficiency and high loading capacity shown, the FGR appears to have good potential as an in-line flotation-separator device in applications requiring high rate solid-liquid or liquid-liquid separations.

Jan 1, 2005

Recovery of gold by smelting zinc dust concentrate has been carried on at Lake View and Star, Ltd., since July, 1930, when the Merrill-Crowe precipitation plant was first put into operation.Part I describes the development of current gold-room practice, commencing with the clean-up of the MerrillCrowe plant, a procedure that has not materially changed since its inception, and then shows how modifications to straight roasting and smelting became necessary, following a gradual increase in the copper content of the ore treated by the mill.Present smelting practice converts most of the copper into a mixed copper-lead matte, thE sulphur being supplied by the addition of flotation concentrates containing about 35% sulphur as pyrite. The process yields gold bullion of a sufficiently high grade to send to the Royal Mint, but until 1943, suffered from the disadvantage of giving matte and slag by-products high in gold and silver, that were not recovered directly but had to be sent to a smelter.Part Il gives details, of experimental work cnrried out since 1943 which led .to a process for the satisfactory and economic recovery of not only the gold and silver, but also the copper from these, hitherto, troublesome by-products. Nevertheless, incidence of matte in a smelt has always been considered undesirable, and it is hoped that eventually it will be obviated by removing most of the copper from the zinc slime before smelting.Part III indicates the methods by which this might be achieved, and outlines the experimental work that has been done up to the present.

Jan 1, 1948

By G N. Phillips

Global annual gold production has been remarkably constant over the last decade at ~2500 t/a3. The major producers today are China (annual production over 350 t and rising), Australia (250 t), USA (240 t), Russia (200 t) and South Africa (190 t and falling); these figures are representative of recent years but approximate. Demand from jewellery, investment, industrial and dental uses has been in excess of mine production for the last decade, by approximately 1000 t/a.Ongoing exploration is the life-blood for gold mining, and more so than for many other metals. Explorers consider sovereign risk, security, labour costs, commercial terms, land availability and inherent geologic prospectivity to determine where to focus their activities. Exploration success over the last decade has been shared by established major producers like Australia, Canada and USA, several countries in West Africa, and many parts of the Pacific margin. Although gold-only deposits have dominated world gold production historically, the gold-plus types, especially copper-gold, are becoming more important.Australia experienced a major period of exploration success from 1979 that has led to annual gold production rising from 17 t in 1979 to 250 - 300 t/a recently. Today, Australia has economic demonstrated resources of over 9000 t Au, which has risen progressively from 220 t in 1979. The majority of production has come from gold-only deposits in the Yilgarn craton in the southern half of Western Australia, but there are a few large Proterozoic deposits in central Australia including Olympic Dam, Telfer and Starra, which are mostly gold-plus types with copper and gold. Large goldfields in the younger host rocks of eastern Australia include the gold-only deposits of Victoria and North Queensland, and gold-plus deposits of New South Wales.CITATION:Phillips, G N, 2013. Australian and global setting for gold in 2013, in Proceedings World Gold 2013 , pp 15-22 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By K Williams, A Lavrinec, V Gurung, D Ilic

The moisture content of iron ore during handling can range from the dust extinction moisture at the point of arrival at the port to the transportable moisture limit at the point of loading ships for maritime transport. Moisture content and ore composition, specifically fines content, have a large influence on ore flowability. Typically, elevated moisture can result in bottlenecks, downtime and lost productivity due to build-up, conveyor carry-back and blockages, increasing maintenance costs. On the other hand, low moisture can result in increased dust emissions influencing the environmental footprint and product losses. Managing the use of water across the supply chain is therefore critical for service life of equipment, productivity, but also has environmental and social impacts, affecting the social license to operate. Previously, experiments have shown that oscillations induced in iron ore during handling and transport can result in movement of moisture through the ore. This kind of moisture migration depends on the nature of these oscillations, such as the undulation of idlers during conveying, the inherent ore properties and the initial moisture content. Moisture has been observed to move either upwards and/or towards the bottom of the burden. These effects can be exploited to remove excess water from the ore influencing handleability and operation, however, the actual mechanisms of moisture migration are currently poorly understood. The study presented herein involves the use of simulation to examine moisture and ore interactions. Simulations using discrete element method (DEM) and coupled with smoothed particle hydrodynamics (SPH) are implemented to investigate the behaviour of moisture in wet ore in the presence of oscillation. This is conducted at a fundamental level first using glass beads and water which is then compared to iron ore at high moisture content. The results of the modelling are discussed in view of experiments conducted.

Sep 18, 2023

For some time fine coal (-0.5 mm) flot ation has been considered as a bulk flotation problem. Combinations of hydrocarbon oils and frothers have been used as surface active agents in coal flotation. The selectivity of the flotation process has always been poor in such cases. With the increase in fine coal production due to mining methods and coal handling systems, optimisation of fine coal treatment.has become important. Petrographic and mineralogical composit- ions of coal particles have been reported to influence their flotability. The problem becomes more complex due to surface oxidation of coal and the presence of slime forming clay minerals in the run of mine coal. In this paper, the flotation problem is examined on the basis of various constituents of coal and their associated gangue minerals. The selection of reagents has been suggested on the basis of their surface chemical properties. Factors such as surface modific- ation of coal and gangue materials, flotation kinetics and hydrocarbon oil - coal inter- action have been critically evaluated to improve fine coal flotation recovery.

Jan 1, 1978

Diamonds occur in N.S.W., Victoria and north west Tasmania. Diamonds from different areas appear to have their own characteristics, lending weight to the suggestion that three or four different sources (different in location and age) have produced the diamonds found in alluvials at quite a number of locations in Eastern Australia. Explorers for kimberlites in Victoria must overcome a number of field difficulties. The writer's approach attempted to find exploration targets by literature search, noting unusual garnet occurrences, and by relating records of diamond occurrences to described mining activity. While the records are biased towards gold, the study did lead to a pipe, located well away from known diamond-bearing alluvials. Core from one test hole has shown this intrusive to include an alkaline ultramafic breccia with many kimberlitic affinities - a breccia containing mantle-derived minerals, but not a true kimberlite. (A detailed rock description is appended to this paper, but is not the purpose of the paper.) This result enhances the possibility that kimberlites may occur in Victoria, on or near large scale faults or grabens. The depth of fracture penetration may have been different

Jan 1, 1979

By Y G. Anoman

This paper discusses the operating model within Endeavour Mining Corporation regarding the options of owner mining against contract mining. It’s based on the concept of ‘are we carrying out the most efficient mining’ regarding cost and performance. This question can only be answered through an extensive contract mining tender process and conducting a comprehensive comparison to evaluate the transition viability. Karma mine, located in Burkina Faso, is the subject of this paper. The Tender model included sales of equipment, parts and tooling associated with the traditional Load and Haul Schedule of Rates (SOR). The methodology focused on the structure of the tender process, which consists in the development of a SOR based on haulage profiles and mining schedule. This is a new Endeavour framework that allowed the bidders to compete on an even level. This was performed using a systemic analysis which encompassed all the elements involved in a transition such as the Human Resources (HR), taxes and customs implications, directs and non-direct costs (Finance and interest on assets, depreciation, insurance), contractor risk profiling. It was assessed against the normalised internal pricing tender-based. This paper gives an insight into how a West African mining operation addressed the sensitivities of the HR functions against the commercial aspects. This was one of the most successful transitions in West Africa and was carried out during the COVID crisis. The outcome of this project has created value by detailing a lesson learned model for both commercial and HR aspects. This discusses the commercial comparisons along with the internal model with the underlying HR functions as a risk factor that could have jeopardised the continuation of the operation. This resulted in a smooth transition with the additional cash flow generated by the sale of the parts and equipment turned Karma into a viable operation.

Jun 22, 2022

By Pate W. T

This paper describes the development of a dynamic flowsheet simulator for comminution operations. Object oriented software design allows the handling of multiple ore types, blended into multicomponent feed streams. Software objects have been c

Jan 1, 1998

By B Mennie, R Poedjono, G Coad

PT Freeport Indonesia operates a large copper and gold mining operation near Tembagapura, Papua (formerly, Irian Jaya), Indonesia. This is a remote location with its own set of unique operational characteristics. The mining and concentrating operations typically produce a concentrate containing 2500 tpd of copper and 6000 oz of gold per day from the combined mining of a 45 000 tpd (ore) block cave operation (DOZ Mine) and a 190 000 tpd (ore) open pit mining operation (Grasberg Open Pit). The Grasberg Open Pit mine will be exhausted in 2015 at which time FreeportÆs operations will entirely underground mining methods. The Common Infrastructure Project (CIP) incorporates the elements required for the shift to underground mining at a production rate approaching 200 000 tpd. The AB Adit portion of the CIP will provide deep level access to the Grasberg Block Cave (below the Open Pit), Kucing Liar, Big Gossan, and the Mill Level Zone orebodies. Commencement of the project was September 2003. The Grasberg Block Cave is planned to start production in 2014. This paper provides details on the project scope, innovative contractual framework, advancement of mining methods throughout the life of the operation, equipment selection, manpower selection, training, geological, and socio-political conditions related to the project.

Jan 1, 2005

Production scheduling of open pit mining is a key area as it deals with the management of operating cash flows of mining companies. The efficiency of long-term schedules is usually assessed with economic criteria such as net present value (NPV), discounted cash flow rate of return (DCFROR) and payback period, which are not sufficient on their own for revealing the complex picture of the decision-making process.This paper offers a thorough analysis of the most important contemporary criteria of long-term production scheduling, as way to provide the mining practice with a new approach to the decision-making process. The list of criteria includes technological, economic and probabilistic ones. A detailed case study is provided aiming to illustrate the applicability of the criteria for comparing the scheduling approaches regarding the economic interests of a mineÆs owner and contractor. The results obtained can be used for revealing new trends in the current methodology of open-pit production scheduling optimisations.

Sep 26, 2011

Incidental to the progress of a geological survey of the Kalgoorlie goldfield during 1927 - 1928 a number of specimens of telluride minerals were obtained, chiefly with the help of Mr F G Brinsden, general manager of the South Kalgoorlie mine, and Mr Ernest Williams, general manager of the Boulder Perseverance mine. This collection was supplemented by a number of small specimens, including the rare copper telluride, which were collected and preserved from the Kalgoorlie mine by Mr A E Paton, and also by a few miscellaneous specimens from the collection of MrS F C Cook, of the Palace Hotel, Kalgoorlie.An extensive knowledge of the rare tellurium-bearing minerals was compiled during the last century from occurrences in Transylvania and Colorado. The recognition of different species has been based on chemical analyses and crystallographic measurements. In a few species there has been an absence of crystalline form, and these, together with the discoveries in this century of rickardite and 'weissite', muthmannite and empressite, have depended chiefly on the chemical analysis for identification. On the other hand, the crystalline form of nagyagite and stiitzite has been described in detail, while their precise chemical formulae were doubtfully defined.The announcement of the occurrence of tellurides at Kalgoorlie by A G Holroyd in the Kalgoorlie Mine on 29 May 1896, followed by their discovery in comparative abundance, stimulated the further study of these minerals. In this locality there is a general absence of well-formed crystals, and the knowledge gained has been confined to the record and description of previously known, but exceedingly rare, species.No new species has been recorded, but the intimate association of various species resulted in early description of two supposedly new species, kalgoorlite and coolgardite. These have been discredited since the investigation by L J Spencer in 1903, based on a collection of specimens donated to the British Museum.Spencer's list of species at Kalgoorlie comprises calaverite, sylvanite (or krennnerite), petzite, coloradoite, 'and altaite, and does not include hessite, previously mentioned by Krusch. In 1912 melonite and a copper telluride were added by J A Thomson and the presence of hessite confirmed. In 1912 there also appeared a full and detailed account by E S Simpson on behalf of the WA Geological Survey, which embraced his earlier notes on the tellurides, and which represents the state of our knowledge of the Kalgoorlie minerals, practically as far as can be attained without the use of the reflecting microscope.The position has been stationary for about 18 years, and it was thought. that the best use to which the present collection of tellurides could be devoted was an attempt by mineragraphic methods to study the mineral relationships, not only of the tellurides among themselves, but also to gold and other associated minerals. The precise mineral content and relationships become a factor of added importance with the development of flotation methods of treatment at Kalgoorlie.Moreover, the study would supplement the description of the ore deposits of the Boulder Belt that has recently been published.

Jan 1, 1994

By G Lumley

Gold miners have been underperforming the price of gold for a number of years. So why has the æmarketÆ undervalued our gold miners relative to what they have been mining? The low valuation ascribed to gold mining companies is largely attributable to their profit performance. In the period since 2006 the price of gold in A$ has risen about $900/oz, but the real cash margin (operating cash costs + cost of finding and/or acquiring deposits + the cost of bringing them into production) has only risen about A$100. Rising operating costs are a major part of this reduction in real margin. Energy and labour costs have risen more than the inflation rates across a number of countries as have taxes, royalties, etc. There are however, more significant contributors to the rising cost base. Firstly, in 2006 the average gold grade was 2.0 g/t; today it is 1.3 g/t. Secondly, strip ratios (for surface mines) have increased by 19 per cent during this time. Open cut mining equipment unit output across the world has dropped by 26 per cent during 2006 - 2012. Finally, costs have risen by 55 per cent during this time period. Consequently, there is now 3.8 times more mining cost required to produce an ounce of gold from surface mines compared with 2006. The decline in gold grade looks to be a permanent trend as does increasing strip ratio if output is to be maintained. Costs will continue to rise although cost control will be necessary. Reversing the decline in equipment performance and closing the gap between median and best practice provides the hope for a sustainable reversal of cost increases. The current gap between best practice and median performance has grown to 112 per cent for mining trucks, 168 per cent for excavators and 169 per cent for front end loaders. Closing this gap is the potential for a more profitable future. For most gold mining companies improving mining efficiency is not an option; it is an imperative.CITATION:Lumley, G, 2013. How many gold mines will inefficiency kill?, in Proceedings World Gold 2013 , pp 267-276 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

Any future developer of underground mining on the Bendigo goldfield will need to understand the unique geology and gold occurrence of this field. The development and sloping system employed will be primarily designed around these unique features. Modern techniques and equipment used in narrow vein mining will be applicable in this situation.The purpose of this paper is to examine the important geological features of the field as well as the known historical occurrences of the type of gold deposition in the ore bodies. This information will point to a system of development and extraction which will accommodate these features.

Jan 1, 1993

By S McKnight, L Koroznikova, S Hall

Mineral sands represent an important new resource being developed in the Murray Basin, including parts of western Victoria. This paper will outline a simple methodology for mineral sands characterisation, developed as part of the AMIRA-managed project P777 æThe Development of Heavy Suspension Techniques for High Density Separations (Replacement of ClericiÆs Solution)Æ. This project is currently sponsored by three multinational mining companies (De Beers Consolidated Mines, Iluka Resources Limited and Rio Tinto Limited) and is developing an innovative laboratory mineral characterisation procedure that will allow the replacement of the currently employed highly-toxic chemicals.Mineral sand resources almost always contain more than one valuable (and relatively heavy) mineral. Titanium minerals are found with a large range of titanium contents, giving rise to density variation and often subjective mineralogical descriptions. Companies tend to rely on laboratory heavy liquid separation in the evaluation of samples arising from exploration, mining or metallurgical processes. Unfortunately, there are only a limited number of high density (æheavyÆ) liquids and these tend to be more toxic as their density increases. Low-toxicity inorganic solutions, based on tungsten compounds, have been developed that can be utilised at relative densities (RD) up to 3.0. However, beyond this value currently only organic liquids can be used. Diiodomethane (methylene iodide) having a relative density of 3.31 is commonly used; however, this presents significant health and safety hazards. Mixtures of thallium formate and thallium malonate were found in the early 1900s by Clerici to provide liquids having specific gravities between 4.0 and 5.0, hence æClericiÆs solutionÆ. For the characterisation of the heavy components of mineral sand deposits (eg anatase sg 3.9, rutile sg 4.2, ilmenite sg 4.4 û 4.7 and zircon sg 4.6 û 4.8) there is currently no heavy liquid alternative to ClericiÆs solution. ClericiÆs solution is highly toxic and testing is now conducted by very few laboratories worldwide with costs reflecting the chemical costs (though extensive efforts are made to recover and reuse the liquid, plus the requirement of its removal from the mineral samples), the infrastructure costs and health and safety regimes (eg blood testing of exposed staff, inventory management). A simple laboratory technique of density fractionation is being developed, employing suspensions of fine tungsten carbide particles in lithium heteropolytungstate (LST) solutions, that can replace ClericiÆs solution in the evaluation of fine mineral sands samples (eg -250+150 microns). The developing methodology that can achieve low-cost, low-toxic separations at relative densities above 5.0 will be outlined and the comparison of results with ClericiÆs solution presented.

Jan 1, 2006