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By P J. Grobler

The current commodity boom is depleting the ore bodies at a rate not seen in the past. As the existing ore bodies get depleted, only the more inferior bodies are left for exploitation. This places an emphasis on beneficiation to upgrade the lower grade ore to high-grade feedstock for downstream processes. This paper discusses the role of dense medium separation in this quest for high-grade feedstock for the future. It covers the production and utilization of ferrosilicon and gives a future perspective of the technology. It concludes about the way ahead and the challenges facing the processing fraternity and mining industry.

Jan 1, 2006

By Russell J. Foster

Many important materials are derived entirely or partially as byproducts of primary copper, lead, and zinc production. This U.S. Bureau of Mines report examines the collective role of byproducts with regard to the economics of domestic mineral production, and their individual significance in terms of dollar value, end uses, and strategic considerations. The study also analyzes circumstances that have affected the competitiveness and structure of the U.S. copper, lead, and zinc industries, and factors that impact byproduct availability. These factors include production capacity at smelters and refineries, process technology, changing sources and composition of ores, regulations, foreign ownership, and byproduct demand and price. Policy considerations regarding stockpiling, regulations, and research are assessed.

Jan 1, 1991

SOME notes on the works of the Electrolytic Refining and Smelting Company of Australia will no doubt be of interest to members of the Institute, more especially as much of the work is new to Australasia. As many of the members who may read this paper have not been in a position to visit works of this kind, and are consequently not thoroughly acquainted with all the operations carried on, the author has taken the liberty, in some cases, to enter into explanation which would otherwise be unnecessary. The works are situated at Port Kembla (New South Wales), about fifty miles south of Sydney, and are approachable both by rail and water. The Government has recently built a low-level jetty upwards of five hundred feet long, and intends installing at an early date an electrically operated portable crane to facilitate the handling of material to and from the boats. This will mean: a considerable reduction in the length of time that boats are laid up at the jetty. There are also under construction two breakwaters, which, when complete, will materially assist shipping operation...

Jan 1, 1910

By R. M. Sweetin

Detailed descriptions by operating area of the Kidd copper smelter are presented, together with accounts of complement staffing, training, and preparation activities for smelter start-up in June 1981. Concentrate tonnages smelted in the first twelve months of operation were constrained by the capacity of the furnace off-gas system. However, modifications designed and introduced over that period, plus sustained efforts by operations and maintenance personnel have resulted in stepwise improvements in smelter performance.. Consistent operation at design feed rates has been well demonstrated over the third and fourth smelter campaigns and efforts continue on further improving the continuous smelter on-line times and increasing campaign life. In November 1982., following a seventeen month preproduction period, the Kidd smelter attained full operating status.

Jan 1, 1983

By H. P. LeVan

The aced for reliable reserves of the essential element, manganese, has been a continuing concern of the Federal Government for more than three decades. Because of the increasing vulnerability of outside sources of supply efforts have been intensified to find a means for beneficiating United States domestic deposits. The deposits of most interest would of necessity be near, or have access to, suitable transportation to processing plants. The Georgia manganiferous iron deposits represent some 10 million tons4 of ore readily available to southern iron and steel industries, if a manganese recovery process capable of functioning in the presence of large quantities of iron can be developed. In addition, a successful method for beneficiating the Georgia ore could produce a significant quantity of high-grade iron concentrate. The Differential sulfatization process developed 47 the Bureau of Mines5 seemed to be well suited for this application, particularly because it results in low concentrations of iron in the leach liquors with relatively complete extractions of manganese. In this process, manganese in the presence of iron is preferentially reacted with sulfur dioxide at elevated temperatures and subsequently extracted with water.

Jan 1, 1962

By Uusna S, Canning R. G, Goodheart B. A

The development of a process for removal of iron oxides from ilmenite is outlined whereby the Ti02 content of Western Australian ilmenites can be upgraded from 55 to approximately 90 per cent. In the first stage, the iron oxides are reduced with solid carbon (coal) to metallic iron. Experimental reductions were carried out in crucibles, a fluidized bed, and a small pilot plant rotary kiln. The reduced ilmenite was then agitated in aerated water, in the presenceof catalysts, so that the iron "rusted" away from the ilmenite grains and the precipitated iron oxide was easily separable by decantation.The influence of variables on the rates of reduction and oxidation are discussed. The oxidation rate was examined for both the physical oxygen transfer characteristics and electrochemically by reference to Pourbaix diagrams, in which redox potential is plotted against solution pH.The upgraded ilmenite is expected to be an attractive material for pigment manufacture, and the iron oxide has prospects of being a marketable by-product. The process may possibly be applied to other ores.INTRODUCTIONThere are extensive deposits of ilmenitic beach sands, Le. iron titanium oxides of the general formula FeTi03, 'occurring in the lower south-west portion of Western Australia, and although there has been considerable commercial development, local producers face keen competition on a freight-cost basis. Thus the removal of the unwanted iron oxide constituent would have the double advantage of reducing the freight differential and presenting a more attractivematerial to pigment manufacturers.

Jan 1, 1965

By Neo Molelekeng, Jocelyn Bouchard, Rebecca Monnapula, Martin Émond

"Xstrata Alloys – Eland Platinum concentrator (South Africa) has recently been commissioned and is now initiating a challenging optimisation program encompassing the entire operation. Process control improvements are key elements of the program and initial results have demonstrated how leveraging from current assets can bring significant improvements through overall reduction of variability. This paper gives a brief overview of the operations and details how Eland is striving to become a top tier leader with advanced regulatory control strategies recently implemented. Results reveal that what can be achieved in a standard control system (PLC or DCS) should not be underestimated as the first interventions led to a steadier operation of the primary ball mill circuit. Following the improvements, significant and sustained reductions of standard variation were observed for key process variables around their set-point: primary ball mill feed rate (72 %), rougher feed density (58 %), and rougher feed flow rate (47 %). A path forward has been identified to tackle further opportunities around the primary grinding circuit: water balance management, throughput optimisation as well as charge and power draw control.INTRODUCTIONThere are numerous approaches to mineral processing plant optimisation. As the benefits of determining the right reagent types, mix, dosage and addition points, or the proper charge of grinding media in a mill are fully appreciated, there is still nowadays some misunderstanding and misconceptions about process control in general and how it can contribute to the whole optimisation process. The confusion between the various disciplines involved, i.e. instrumentation, control system programming, automation and process control, certainly does not serve the best interest of the industry with this regard."

Jan 1, 2010

By Iván E, Alex Araya Jofre, Jean Guiroux Toro, Eduardo Valdés Guerra

Currently, it is important for companies to have controlled mining operations and adhere to production schedules. To achieve this, one of the key factors is maintaining high reliability in the P&T process, primarily the opening of ore stope, which could be delayed due to any unplanned or uncontrolled problem. These ore stope opening processes, whose main activity is generating free face, are a very important pillar for future mine planning. The possibility of ensuring their opening brings a series of downstream benefits: safety, economics, productivity, and compliance and adherence to plans. The process under discussion consists of developing free faces in a single blasting event. This will help us leverage greater reliability for overall production operation plans, reduce construction times, and open up opportunities for downstream improvements in the production process, considering technical factors in P&T designs. This study presents a developed methodology and shows the results of its implementation in ten (18) single-event free face blasts. The analysis includes cavity geometry, geology, rock qualities, drilling deviations, and the blasting strategy implemented for each event. The methodology used considered material fluffing processes, the actual drilling trajectory, the initiation sequence, QA/QC during explosive loading, monitoring instrumentation (vibrations), and VOD recording, among others. As a result, out of a total of 18 free-face events blasts in a single event, 16 were successful and two achieved 90% efficiency, reducing the stope's production start-up time by 50% compared to current operations. By implementing free face blasting in a single event, there are savings in operating costs, increased productivity of the mining equipment, and improved adherence to production plans. For applications with greater heights of free faces, where blasting cannot be carried out in a single event, we should consider performing them in two stages using wireless detonators already available on the market for mining operations.

Jan 26, 2026

By F. R. Lee

[WHEN the Bureau of Mines was established in July 1910, one of the problems immediately attacked by the new organization was the development of standard, for the design and testing of electrical equipment that could be used without fear of initiating fires and explosions in underground coal mules. Research and investigation by Bureau personnel, supplemented by the published results of similar work by European mining authorities, led to the establishment of standards or "schedules." which guide manufacturers in the design of many types of electrically operated machines and devices used in. underground coal Mining. By issuing these standards, Bureau personnel establish the requirements to be met by such equipment before it tan be approved by the Bureau of Mines as permissible for use in gassy coal mines. Every 2 years the Bureau of Mines publishes a list of equipment that leas been accepted as approved or permissible during the preceding 2 calendar years. This is done to inform the mining industry of the availability of the latest equipment for safe use underground.]

Jan 1, 1964

By Gino Vogt

In mechanized tunnelling operations, performance, consumption and safety are main factors for jobsites. One of the most important components effecting these factors, especially in slurry TBM operations, are Slurry Treatment Plants (STPs). Inadequately dimensioned and designed STPs create bottlenecks for tunnelling operation and jeopardize time schedules and performance. Inefficiently planned STPs could drastically increase consumption figures such as electrical power, bentonite, water polymers, etc. Inaccurately selected and treated suspension properties can cause a high-risk potential for the whole project. This paper debates the relevant key parameters for STPs from start to finish of a project and its results in influencing factors from the manufacturer’s point of view.

Dec 1, 2022

By McHenry Mosier

This paper describing mining practice at Morenci, Ariz., is one of a series of articles on mining method, and practice in the various mining districts in the United States. At present (1929) practically all the mineral production in the Morenci district is from the Humboldt mine of the Morenci Branch, Phelps Dodge Corporation. The mining method used is adapted to the type of ore body being exploited; it has been developed by adopting methods used elsewhere and making necessary changes to fit local conditions. Improvements in current practices are still being made.

Jan 1, 1929

By Evelynn Stirling

Agenda ? Emissions legislation ? Cummins Tier 4 Technology ? Cummins Experience with Technology ? Operation and Maintenance Impact The Emissions Challenge ? The 2014/5 emissions regulations present the most significant challenge to our customer?s diesel powered equipment design and operation in recent history? ? ?and Cummins has the solution.

Aug 1, 2013

Experimental results are presented that test the hypothesis that the descaling behaviour of stainless steel slabs following reheating is controlled by interfacial roughening at the scale-steel interface. In this investigation, two stainless steels were considered: type 304 (austenitic, with 18% Cr and 8% Ni) and type 412 (ferritic/martensitic, with 11.6% Cr). It was found that the entanglement that arises at the scale-steel interface was in fact effective in maintaining scale-steel adhesion, under the mechanical descaling conditions used. In the case of type 304, descaling proceeded by fracture along chromite layers, which formed (by internal oxidation) on the austenite grain boundaries; for this steel, the extent of descaling depends most strongly on austenite grain structure, and not primarily on the conditions in the reheating furnace. In contrast, type 412 samples descaled only at the edge of the entangled zone, and showed a greater sensitivity to the reheating conditions; specifically, higher free oxygen in the reheating gas and longer reheating times were found to increase the residual scale thickness. Key words: stainless steel, reheating, scale, entanglement, descaling, fayalite, internal oxidation, grain structure, free oxygen.

Jan 1, 2003

By J. Kretschmann

Mining heritage can be of outstanding value for many regions around the world, because mining has been done for thousands of years for the benefit of mankind and its development. This paper presents an ongoing project creating a general guideline for the handling of mining heritage on the basis of experiences made in Germany. Interactions of stakeholders in the ?heritage network? as well as strategies for the technical proceeding will be described. An action plan for the sustainable handling of mining heritage has already been developed in part, which includes necessary measures. Best-practice recommendations will be derived. Keywords: m ining heritage / preservation / guidelines / action plan / Sustainability

Feb 27, 2013

By Martin Williams

During the coming decade, many of the first generation of ‘super-pit’ gold and base metal mining operations in North and Latin America will reach the end of their economic lives. The closure of such pits in a manner which is environmentally sustainable presents a considerable challenge to the minerals industry. Pit closure often results in the partial or total inundation of formerly dewatered mining operations, and the resultant formation of lakes. The development of techniques for predicting, and controlling, the chemistry, groundwater discharge characteristics and long term hydrospheric impact of these lakes has become a critical aspect of pit closure planning. In this sense, the paper point out that Sleeper Mine was the first of a new generation of open pit gold mines developed in Nevada, USA. The closure of the Sleeper pit exemplifies the use of a range of pragmatic approaches to pit flooding, with applicability to mine closure at many other sites throughout the Américas.

Apr 22, 2003

Gas well tests were performed on 17 wells in the Roma area. The procedure used in the test programme incorporates an initial isochronal test followed by what is described as the "two flow drawdown" technique. The second flow of the two flow drawdown test was conducted for sufficient time to allow transient investigation of the surrounding reservoir. This combination of tests allows the evaluation of stabilized production capacity in addition to the determination ,of several important reservoir characteristics.It also provides a qualitative indication of reserves, by reflecting the presence or absence of reservoir boundaries within the drainage area affected during the test.

Jan 1, 1968

By J. Ritchey

This report describes the engineering feasibility and economic advantages of using a mobile bridge-type cross-pit belt conveyor system in conjunction with a large dragline to excavate and transport spoils in a typical Western surface coal mine. The studies show that such a system could be built to survive operational and climatic mining conditions, and that its implementation would offer a reduction in both acquisition and operating costs versus conventional mining units of comparable capacity. Reclamation costs can also be significantly reduced, and the total reclamation process accelerated, making the cross-pit conveyor system attractive to mine owners and environmentalists alike.

Jan 1, 1976

This publication summarizes, for potential contractors and all other interested parties, the research and development of in-house and contract projects programmed by the Bureau of Mines for fiscal year 1983 (October 1, 1982-September 30, 1983) under its Health and Safety Technology program. The objective of these projects is to provide an ordered and sequenced series of advance toward the Bureau's overall goal of providing the systems technology required to create a more healthful and safer working environment for the Nation's mining and minerals processing workers.

Jan 1, 1982

By Stuart Brashear, Eddie Colburn

The Birmingham Coal and Coke – Knight Mine is a single seam coal mine in central Alabama. As pit development progressed in 2013, concerns over increasing vibration levels resulted in modifications to the blasting program that inhibited shot size and coal recovery. By January 2014, while still over 1,400 feet (427 m) from the regulatory seismograph, vibration levels climbed above 70% of the mine permit limit, even with triple decking of holes and reduced burden and spacing. At this time the decision was made to commit to the use of signature waveform analysis and precision programmable electronic detonators to minimize vibration and maximize the amount of coal that could be recovered before vibration levels reached permit limits.

Jan 1, 2015

By G. R. Corbett

Between 1977 and 1984, No. 26 Colliery, at Glace Bay in the Sydney Coalfield, suffered from a series of 37 rock/gas outbursts. These events were characterized by the complete pulverization of a sandstone which was propelled into the mine roadway and an associated release of methane gas. The events began to appear at a depth of 700 m and increased in intensity and damage to the excavation as the mining depth increased. At the time of the closure of No. 26 Colliery (as a result of an unrelated fire), these outbursts were the subject of intensive investigation. Although No. 26 is now closed, there is concern that similar events could appear at Phalen Colliery where current development work is proceeding at a depth close to the 700 m threshold. Past investigations into rock/gas outbursts included studies of in situ stresses, the simulation of outburst events in the laboratory, investigations into the potential for destressing an& degassing of problem sandstone and the development of numerical models to assist in the design of openings in outburst prone ground. However, despite this work, methods of predicting outburst conditions are presently limited to examination of probe hole cores for core discing, and methods of working under such conditions are limited to boring and firing and using volley firing techniques to initiate any outbursts while workers are safely out of the heading. During this investigation of worldwide occurrences of this phenomena, literature obtained suggested that outbursts might generate microseismic precursors. An intrinsically safe (IS) microseismic monitoring system was designed and developed based on CANMET's rockburst monitoring system currently in use in hardrock mines, and installed in a development roadway at the deepest extent of the Phalen Colliery. The system will record microseismic activity associated with development work to try to identify characteristic precursors of outburst-prone conditions. This paper describes the steps taken to identify a microseismic system suitable for use at Phalen colliery, of which part of the requirement was that it be IS and approved for use in the Sydney Coalfield. The modifications to the selected system are described, along with its capabilities and the preliminary results of its performance over the first few months of use.

Jan 1, 1994