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By P. Fauvel, V. Nasri

In January 2001, French and Italian governments signed an agreement for the construction of a new Lyon-Turin railway line. This project includes a tunnel of 53.1 km length and a maximum of 2500 m overburden to be designed for a reference speed of220 km/h. The tunnel crosses major part of the West Alpine geological formations, which are very complex and contrasted in terms of the nature of rocks and the mechanical and hydrogeological conditions. In addition to the twin single-track tubes, numerous intermediary shafts, security station and intervention sites and cross passages should be built to respond to the security, operational and construction requirements. This paper describes the results of the preliminary engineering design and multiple challenges of this very long and deep railway tunnel.

Jan 1, 2005

By Gregory Molinda

NIOSH has recently completed a study of the interaction between polyurethane (PUR) and coal mine roof in order to determine the mechanism of reinforcement, in both highly fractured rock and unfractured rock. Four case studies of PUR rein­forcement are presented. At a West Virginia site, a borehole camera revealed the location of roof voids and guided the PUR injection. By injecting polyure­thane into a zone from 0.6 to 1.8 m (2?6 ft.) high in the roof, a roof beam was created and ongoing intersection falls were halted. In another highly fractured roof in a western Pennsylvania mine, a total of 5.8 cm (2.3 in.) of rubbleized rock was found in a zone up to 3 m (10 ft.) into the roof. Untargeted PUR injection filled approximately 1/2 of the fractures. These two case studies showed that it is not necessary to fill up 100% of the void space to create stability. In the other two field sites, polyurethane was injected into weak, but unfractured roof. Post-injec­tion video monitoring showed that weak bedding planes were hydraulically wedged open and polyure­thane injected along bedding. The reinforcement value of this injection method is limited because of the wafer-thin layer of PUR introduced along bedding, and the lack of a PUR ??webbing?? which would serve as a structural framework to provide strength. It was determined that video inspection prior to PUR injection can aid in identifying the fracture zones to target, and minimize ??blind?? pumping and loss of PUR.

Jan 1, 2008

The whole of the iron ore required by the Broken Hill Proprietary Company Limited at the Newcastle Steel Works, and Australian Iron and Steel Limited, at Hoskins' Kembla Works, is drawn from the Iron Knob, Iron Monarch, Iron Prince and Iron Baron deposits situated in the northern part of Eyre's Peninsula, South Australia.The Iron Knob and Iron Monarch deposits are near the township of Iron Knob, approximately 42 miles W.S.W. of Port Augusta, whilst the Iron Prince and Iron Baron deposits are some 18 miles due south from Iron Knob, in another group of leases, the adjacent township being known as Iron Baron.The ore mined at Iron Knob, Iron Monarch, Iron Prince and Iron Baron is conveyed on the Company's 3ft. 6-in. gauge tramway to Whyalla, on the western side of Spencer's Gulf, approximately 45 miles south by west of Port Augusta whence it is shipped to Newcastle and Port Kembla.SHORT HISTORY.The establishment in South Australia of the lead smelting industry at Port Pirie, Dry Creek and Port Adelaide in the...

Jan 1, 1937

By K. N. Panigrahi

India bestowed with 6000km of the coastal belt, contains some of the richest and largest placer deposits with a mixture of heavy minerals like ilmenite, rutile, leucoxene, zircon, monazite, sillimanite and garnet. Each of the minerals is having economic value due to its inherent characteristics for industrial use in fields of paints, metallurgy, refractory, abrasive and so on. The reserves of titanium bearing minerals (ilmenite, leucoxene, and rutile) in the country is around 378 million tonnes. More than 90% of the titanium based minerals produced worldwide are utilised for making value added products in the pigment industries. Approximately 8 million tonnes of monazite reserves are available in the country from which several rare earth elements like cerium, neodymium, lanthanum, yttrium etc. can be extracted for use in several industries. The country contains a deposit of about 20 million tonnes of zircon, which is used in foundries, refractories, ceramics and chemicals. India has a reserve of 107 million tonnes of garnet and 131 million tonnes of sillimanite required for the abrasive and refractory industries respectively. Keeping in view the multifarious uses, the beach sand minerals are being exploited to have the economic growth of the nation. Although the process adopted for the separations are simple, the equipment involved are specially designed because of the nature of the material of construction. Starting from the spirals to magnetic separators, all equipments are manufactured outside India, which is not only costly, but the availability also takes much time for fulfilling the import formalities. Unlike open cast mining, beach sand mining is a environment friendly mining because dredging is implemented to cut and pump the loose sand through a slurry pump causing less damage to the surface topography as both mining and backfilling takes place simultaneously. Therefore all out efforts are made to explore the beach sand placer deposits in an economic manner to emerge as a leader in the global mineral industries.

Jan 1, 2005

By Cathy Aimone-Martin, Brent Meins

A comprehensive instrumentation program was implemented at the Howland Hook Marine Terminal on Staten Island, NY during proximate underwater rock blasting in 2014. Forty-two blasts took place over a 4-week period to deepen the 1200-ft (366 m) Berth 3 from -45 ft (-14 m) to -50 ft (-15 m) MLW to accommodate Post-Panamax vessels. Approximately 86,000 yd3 (65,752 m3) were blasted 120 to 9 ft (37 to 2.7 m) from the wharf to a total depth of -57 ft (-17.4 m). Pre-blast planning included developing and implementing a comprehensive monitoring plan and setting vibration and strain limits to protect the wharf. The plan outlined methods to measure vibrations on five corners of four concrete deck sections, on five concrete-filled pipe piles just below the pile cap near deck corners, and in bedrock adjacent to pile sockets. Water overpressures were measured near instrumented piles for 19 blasts closest to the wharf. A total of 19 geophones were secured to the wharf structure and buried 12 ft (3.7 m) in drilled holes.

Jan 1, 2016

Alkaline leaching with sodium carbonate solution adjusted to pH 9·5 to 10·0 preferentially dissolves thorium from a mixture of rare earth and thorium hydroxides. Rare earth sodium carbonates form in the alkaline leaching stage.These are converted to rare earth oxides for use as optical and ophthalmic polishing agents. Quadrivalent cerium is extracted under similar alkaline leaching conditions.INTRODUCTIONAustralia has made significant contributions to mineral chemistry and mineral dressing. As often happens with an industrially immature country, research investigations often outstrip the ability or desire of commerce to exploit them. It is wrong to think exclusively in terms of export of raw materials. Imagination assists in developing world trends. The chemical utilization of mineral sands has interested a group of investigators, chiefly at the Commonwealth Scientific and Industrial Research Organization (C.S.I.R.O.) and, more recently, in the mining industry itself. From an international point of view the highlight of this work was Newnham's (1960) process for the separation of hafnium from zirconium. Earlier work at C.S.I.R.O. investigated the chlorination of rutile, zircon, and monazite. Assuming that titanium tetrachloride would be available in large quantities in the post war years, extensive work was done by Kraitzer, McTaggart, and Winter (1948) on organic compounds of titanium. This work led to the development of heat resistant paints, plastic compositions, and improved organic protective coatings that predated overseas work by up to seven years. (Post, Shiihara and Schwartz, 1961; Anon, 1955). Contributions were made to the production of refractory hard metals (Kraitzer, 1949; Kraitzer and Newnham, 1956). Pilkington and Wylie (1947) and Urie (1947) investigated the production of rare earths from monazite by an acid process.

Jan 1, 1963

By E Apaza, R Neumayr

This paper aims to summarise the discovery of the QTS Central resource, a previously unidentified +1 Mt inferred resource that lies between two major CSA resource systems.The 1.7 Mt at 5.76 per cent Cu, QTS Central ore system represents 1/6th of the CSA mineral resource and was discovered in 2014 based on the accumulation of historic exploration records dating back to 1989.The CSA deposit consists of five ore systems hosted within turbidite-derived siltstones (CSA Siltstone) and lesser sandstones (five per cent) of the Devonian Amphitheatre Group. The host sediments strike approximately north–south with a steep westerly dip and exhibit a well-developed east dipping cleavage. Most CSA mineralisation is hosted within dilation zones at the intersection of cross-cutting structures and is interpreted as epigenetic in origin.Alteration and weak mineralisation, up plunge to the reported QTS Central mineral resource, was initially detected in 1990 during a downhole electromagnetic conductivity (EM) study, where one hole indicated an off-hole conductor, later tested with four diamond holes. One of these diamond holes intersected 3 m at 7.5 per cent Cu at 200 m. Development of the 9070 Subway drive in 2005/2006, linked the QTS North and QTS South workings and intersected structures interpreted to host QTS Central mineralisation. Subsequent drilling proximal to the 9070 Subway in 2007 identified an up plunge extension to the QTS Central zone (UDD07152: 1.8 m at 6.3 per cent Cu from 10.7 m). Work on QTS Central was largely forgotten until 2012 when the mining of a 450 m infrastructure drive provided a platform to test the anomalous grades. In December 2013, drill hole UDD13055A intersected 20.9 m at 7.2 per cent Cu from 378 m. By the end of 2014, the QTS Central inferred resource was 1.0 Mt at 6 per cent Cu and 18 g/t Ag (Hosken and Apaza, 2014). Late in 2016, further infill drilling occurred from two fronts to increase confidence in the QTS Central resource. The results of this drilling are expected late in 2017.The current interpretation indicates the QTS Central system consists of two main lenses hosted within closely bedded sandstones and siltstones. The sandstone in general is not mineralised, being heavily silicified, while the siltstone is mineralised and chloritised. The main mineralised lens is 75–200 m along strike and 450 m high. Massive sulfide feeder structures lie at the core of the two main lenses, although the characteristics of the QTS Central system tend toward the mineralisation being more chlorite-rich than in QTS North and QTS South.CITATION:Apaza, E and Neumayr, R, 2017. The discovery of the QTS Central ore system, CSA mine, Cobar, NSW, Australia, in Proceedings Tenth International Mining Geology Conference 2017, pp 151–156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By N. D. L. Burger

A low noise blast hole drilling system was developed to limit the risk of noise-induced hearing impairment in mining operations. Noise- induced hearing loss has been identified as a major occupational health risk in SA mines. The noise generated by pneumatic percussion drills is a major contributor to such noise-induced hearing loss. This motivated the South African Safety in Mines Research Advisory Committee (SIMRAC) to commission the development of a low noise rock drill system. The system had to be designed, manufactured, tested and demonstrated in a simulated underground mining environment. The specification required noise levels below 90 dBA. Other important design considerations were ease of manual transport, setting up and operation. The primary design concept was to encapsulate a standard SecoS215 pneumatic rock drill in a composite material tube. The tube is pushed onto the rock face by a pneumatic cylinder and is sealed at the rock face by an elastic seal. The drill is pulled towards the rock face by a rope and pulley mechanism fitted inside the tube. This mechanism is powered by a second pneumatic cylinder. The actions of moving and setting the drill require two persons. However, the team can carry out the drilling function itself on several drills simultaneously because of the self-thrusting design. The drill is supported by two camlocks. The exhaust (air containing dust, water, rock debris, oil and grease) is removed from the encapsulating tubes via an exhaust tube to the end of the stope. In this way exhaust noise and air pollutants are disposed of away from personnel. Tests were conducted in a test stope. Noise levels of under 90 dBA were achieved, thereby attaining the primary design specification. This was achieved without materially compromising ease of handling. Penetration rate was somewhat improved compared to that of the standard drill, so that productivity could be maintained. Keywords: Drill, rock drill, quiet, noise, mine, underground.

Jan 1, 2004

A systematic study of groundwater conditions at eight underground mine sites exhibiting a wide range of groundwater qualities throughout Australia has been completed at the WA School of Mines. This has resulted in a new corrosivity classification for groundwater driven corrosion processes for cement grouted cable strand used in the Australian underground mining industry. The new corrosivity classification is simple to use and corrosion rates may be predicted from readily obtained in situ measurements of groundwater dissolved oxygen.

Jan 1, 2008

By P N. Holtham

Magnetic separation is routinely used in the processing of titaniumminerals, and the efficiency of these operations can be determined bymeasuring the magnetic properties of the process streams. The valuable components in the feed to a titanium minerals plant have specific magnetic susceptibilities ranging from -10-9 m3 kg-1 (zircon) to 10-6 m3 kg-1 (ilmenite). However, in an industrial environment, in which the mineral temperature may range from 20 to 120¦C, it is difficult to measure susceptibilities lower than about 10-7 m3 kg-1. Hence laboratory testing of spot samples from magnetic separators is currently required to obtain accurate performance data. This is an inherently slow process and where feed grades are variable, optimum performance of magnetic separators is generally not achieved.This paper describes the development of an inductance-basedinstrument for measuring very low levels of magnetic susceptibilityon-line. The signal from the instrument can be used for process control purposes to maintain optimum magnetic separator performance.A prototype instrument has been installed in the zircon scavengercircuit in an Australian titanium minerals plant. The circuit consists of a roll magnetic separator treating a feed consisting mainly of monazite and stained zircon. The monazite-rich magnetic fraction is returned to the mine site for disposal, while the non-magnetic fraction is recycled to the zircon wet circuit. Splitter positions in the separator are adjusted when the final zircon product fails to meet specification, or the magnetic fraction contains more than 30 per cent zircon. Weekly composite grain counts show that sub-optimal operation of the magnetic separator results in significant zircon losses into the magnetics fraction.Using the instrument, the zircon content of this stream can now beaccurately determined from the measured magnetic susceptibility,provided a correction for the effect of mineral temperature is applied using the Curie - Weiss relationship.

Jan 1, 2001

By Cynthia Faura

Educando para tu Futuro es un proyecto de inversión social dirigido a las comunidades de influencia de la refinería Cajamarquilla. Fue creado en 2013, a través de una alianza entre Nexa Resources y la ONG Perspektiva, con el objetivo de contribuir a la mejora de la calidad educativa y brindar mayores oportunidades de educación superior e inserción al mercado laboral formal. Este proyecto beneficia directamente a alumnos de 4° y 5° de secundaria de las dos instituciones educativas públicas más grandes de Cajamarquilla. Hasta 2019, ha atendido directamente a más de 2000 jóvenes, a través de una intervención educativa integral que incluye tanto las necesidades académicas como el desarrollo psicoafectivo del alumno y su creación de un proyecto de vida. Asimismo, el proyecto involucra a docentes y padres de familia y ofrece un programa de becas para estudiantes destacados.

Sep 20, 2019

Recently discovered Carboniferous bentonites are variable in charadeI and thickness, but being altered aeolian, ash-fall tuffs, they are probably extensive. Most are the Ca-montmorillonite type without the natural swelling characteristics of the Wyoming deposits, but their situation, thickness, and response to beneficiation through cation exchange may give them some potential as sources of future economic deposits.INTRODUCTIONLoughnan and See (1959) gave an account of bentonites and fuller's earth deposits of New South Wales. The most likely potential industrial sources were those occurring in the uppermost formations of the Newcastle and Singleton Coal Measures (Permian) in the Hunter Valley and deposited during epochs not marked by strong contemporary vulcanicity.One feature of the record of known occurrences at that time was the absence of bentonites from the thick volcanic sequences of the Carboniferous, but since this paper appeared, many bentonite beds have been discovered by the writer in the Carboniferous facies formerly known as the "Kuttung Series".The purpose of this contribution is to report briefly on the occurrence, genesis, mineralogy, and economic potential of these deposits which augment possible sources of bentonite near major industrial centres on the eastern seaboard.The potential world demand for bentonite would increase markedly with the trend to pelletization in the steel industry, if its use in this field became more general. More detailed mineralogical studies will be presented in later publications.STRATIGRAPHIC DISTRIBUTIONBentonite occurs at irregular intervals throughout a thick sequence of dominantly continental, plant bearing strata...

Jan 1, 1965

By Jacques Ouellet, Ferri Hassani

"Within the mining industry paste backfill technology has evolved over the last two decades. This technology aims at producing safe and cost effective backfill of high strength. When used as cemented backfill underground the usual practice in the mining operations was to consider the backfill as a component under the production engineer responsibility. With its growing use in various site conditions some problems were encountered. Over time the mechanical characteristics of paste backfill could deteriorate. Investigations on these problems brought an increased understanding of paste backfill chemistry. Effectively, paste backfill is produced with tailings slurry having sometimes very complex chemistry and mineralogy. The bonding agents can be sensitive to the chemistry of these slurries. Today, a new understanding of the complex chemical reactions involved in cementing paste backfill is derived from concrete research literature. Cemented paste backfill is a manufactured product and as thus all steps involved in its making must be looked at. Both the processing engineers and mining engineers need to be involved. The proposed paper will go over the various developments and new understanding gained over the years on paste backfill chemistry. The authors had the opportunity to work with various Canadian mines that implemented paste backfill in their operations. Chemical alterations case study will serve to illustrate the importance of a good understanding of cement and paste chemistry. The authors will then conclude on research orientations needed to bring a more efficient use of paste backfill technology. The crucial role of the processing engineers in the paste backfill manufacturing will be discussed.INTRODUCTIONPaste backfill is usually prepared from a mixture of solids and water containing at least 15% particles smaller than 20 microns with the addition of binders for mechanical strength. Historically, tailings had been classified to extract the fines and only the coarse part was placed underground as sand slurry. Paste fill was researched in the last three decades to enable mining operations to use all the tailings, including fines, in backfill. The outcome of the early studies showed that paste fill provides high strength but due to preparation complexities and transportation problems is expensive. A greater understanding of the transportation mechanisms and advances in dewatering technology in recent years has resulted in more practical use of paste backfill."

Jan 1, 2002

Assuming that a gold ore has been effectively ground to ensure maximum economic liberation of gold, the circuits that will have the most effect on the successful operation of a gold plant will be that of the leaching and carbon-in-pulp circuit (CIP). The reagent and utilities operating costs associated with leaching, adsorption, elution and regeneration would typically make up some 15% of total operating cost, whilst the capital costs associated with these areas is about 16% of the total. Although not largest (capital and operating costs associated with comminution are generally dominant) these items represent a significant proportion of capital and operating cost. Much more importantly, these plant areas represent the primary gold recovery process and their technical and operational efficiencies will have a significant impact on overall plant efficiency. The objective during process design of these sections is thus to develop a design which provides maximum technical and economic efficiency and which is robust to potential changes in ore throughput, mineralogical characteristics and head-grade. Experience has shown that, particularly for longer life and higher-grade projects typical of the South African underground gold mining industry, small changes in recovery and efficiency have a significant value over the life of the project.

Jan 1, 1999

Generating short- and long-term mine production schedules in isolation and independently from each other means that only a local optimum can be achieved when each scheduling phase is carried out. The globally optimal solution however, can be achieved when integrating scheduling phases and accounting for the interaction between short-term and long-term activities simultaneously. This paper addresses the task of integrating short- and long-term production plans by combining the short-term objective of minimising deviation to targeted mill feed grade with the long-term objective of maximising net present value (NPV) into a single mathematical model. A case study is presented which compares the present values of the same stope data set scheduled via separate long and short-term models and than by the proposed integrated model which applies a predetermined penalty for each tonne of metal deviation to target for the respective ore tonnage being processed. This allows an operation to obtain a globally optimal scheduling regime when taking into consideration the cost and loss of value resulting from fluctuations in grade to the mill over the short-term.

Dec 6, 2010

By C. W. Davie

"This paper is the second of a series of progress reports4 on a study of the hydrometallurgy of manganese which is being conducted in an endeavor to make possible utilization of the large deposits of low-grade domestic manganese ores that occur in several States.There are at least four processes in which a knowledge of the action of SO2 gas on manganese oxides at elevated temperatures may prove of value.One of these involves dissolution of manganese from ores. The Bureau of Mines has investigated the hydrometallurgy of manganese by a process in which SO2 gas, a waste product at many smelters, is passed into water to form a solvent for manganese. Although several manganese minerals were readily dissolved, rhodochrosite (MnCO3) was attacked but superficially.5 Recent experiments have shown that a roast at 650 to 9000 C. converts the manganese of rhodochrosite to a form that is quickly dissolved by a weak SO2 solution.6 Introduction of smelter gases containing much as 5 per cent SO2 during such a roast would not add much to the cost of the operation, and might result in the formation of considerable water-soluble manganese sulpate.Another case involves a subsequent step in the hydrometallurgical process, namely, the formation of oxides of manganese with simultaneous evolution of SO2 by the heating of the MnSO4 produced by evaporating its solution.A third has to do with the roasting of zinc sulphide ores containing manganese as a preliminary to leaching. During purification of the solutions to be used for the electrolytic deposition of zinc the iron must be oxidized to make possible its removal. Manganese dioxide has been used for this purpose,7 and since manganese compounds are present in some zinc concentrates,8 it is of interest to learn what happens to the manganese in a zinc sulphide or on roasting, and what portion of the manganese in the roasted product might be available for oxidation."

Oct 1, 1930

By R. Simonson

Agenda ? Need and Introduction ? Interface Management Programs ? Outcomes of Successful Interface Management ? Key Success Factors ? Lessons Learned ? Concluding Remarks Need for Interface Management ? Complex projects ? Larger in scale ? Physically dispersed and delivered remotely ? Involved with several stakeholders ? Risks thus imposed due to: ? Iterative and dynamic nature ? Large information flow ? Document revisions and information updates ? Related sources of Risk: ? Ineffective communication ? Poor work relationships ? Person to job mismatches ? Failure to clarify expectations

Aug 1, 2013

Ore sorting is a high capacity, low cost method of pre concentrating ores and in some cases of producing a marketable concentrate. In most cases it is applied to run of mine material, immediately after primary crushing and screening in sizes ranging from 10 mm to 150 mm. Recent developments in bulk sorting of friable uranium deposits have resulted in machines capable of handling fine materials with sensing and separation being achieved on a zone by zone basis. Modern ore sorting machines rely on the synchronous operation of four internal subsystems, feed presentation, sensing, data processing and separation. A variety of different sub systems is available which can be combined in various forms to produce sorters capable of handling a wide variety of mineral types. The benefits in using ore sorting cover a wide range of situations and are applicable to both established mines as well as new mining ventures. Reduced operating costs, increased productivity, capital savings, energy and resource conservation and environmental issues are all part of the reason why ore sorting is finding rapid acceptance in today's mining industry. The suitability of different ore types for pre-concentration using anyone of the variety of ore sorting systems can be quickly established using computer based techniques which require only small samples of the materials under investigation.

Jan 1, 1980

By C. A. Johnson, K. F. Unrug

The identification of the major subsidence areas in the Eastern Kentucky Coal Field has been made to distinguish the subsidence phenomena on the basis of geographical location. Further, this identification process is based upon selected critical geological, topographical, and mining features in the coal fields. The proposed identification of the regions is derived from a comparison of the subsidence potential in a particular area. The most likely severe subsidence areas are compared to those with the probable low subsidence severity. The combination of certain geological and mining parameters involved allows for the derivation of a classification of the subsidence potential.

Jan 1, 1986

By Lutz Markworth, Evren Ören

"The worldwide demand of ores and the depletion of the high-purity deposits make it necessary to recover ores in increasingly finer size fractions in the feed material. The flotation technology of more than 40 years old plants was not able to recover the ultra fine material. Those slurry tailings ponds now have the chance to be re-processed with PNEUFLOT® technology.The bubble sizes of different flotation technologies have a huge influence of the results especially regarding the recovery of the ultra fine particle sizes.PNEUFLOT® technology of HUMBOLDT WEDAG Coal & Minerals Technology GmbH in Germany was applied to ultra fine Phosphate, Copper and Platinum ores. The results will be presented in this paper.Conventional technology like agitator flotation has its limits in the flotation of fines due to turbulences in the cell. The position of the agitator influences the recovery of the fines. A deep impeller generates a higher froth zone. This helps to catch the medium fines. Due to the static head of the slurry inside the cell, compressed air is required for such cell designs.Column flotation is well known for a good selectivity without having in the first cell a good recovery. This leads to invest in several cleaning stages to reach an acceptable recovery. Further more, compressed air is required to generate the air bubbles to the flotation process, which are much bigger than with PNEUFLOT® technology applied.INTRODUCTIONHigh metal prices are actually the basis to invest in poor deposits or deposits with very fine intergrown ores which have to be milled down to ultra fine powders less than 60 micron. The liberation grade has to be determined by a mineralogical analysis. Polish sections have to be prepared and interpreted by using of a microscope. Figure 1 and figure 2 are showing polish sections of a platinum-nickel ore from Petchenga Nickel at Zapolyarni Mine in Russia. The head grades for rich ore are for copper between 0.05 – 0.15%, for nickel between 3 – 7% and for platinum group minerals approx. 0.15 oz/t. With an efficient flotation technology it can be upgraded to 20 oz/t."

Jan 1, 2009