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In formulating its strategic plan in 1998 the New Zealand Minerals Industry identified two related critical issues facing it. These are, broadly speaking, the issues of access to minerals; and the perception the public has towards the industry and its behaviour towards the environment. This presentation will report on the Industry's response to the public perception issue. The Industry has, through the NZMIA Council, and its Communication and Website Committees, developed and implemented strategies covering: communication through the print media, and through its website www.minerals.co.nz, a long-term educational outreach programme with schools, focussing on the significance of minerals, their contribution to community wellbeing and the negligible long-term environmental effects of the Industry's activities.

Jan 1, 2000

By M. L. Bakker

The ISASMELT? top submerged lance (TSL) bath smelting process was developed in Mount Isa, Australia by Mount Isa Mines Limited (now a subsidiary of Xstrata plc) during the 1980s. By the end of 2011, the total installed capacity of the ISASMELT? technology will exceed 8 000 000 metric tons per year of feed materials in copper and lead smelters around the world. Commercial plants, operating in Belgium and Germany, are also batch converting copper materials in ISASMELT? furnaces. This TSL technology is equally effective for continuous converting processes, in which role it is called ISACONVERT?. This paper presents the recently patented ISACONVERT? process for the continuous converting of nickel and platinum group metal (PGM) containing mattes using the calcium ferrite slag system. The paper focuses on the potential application of the ISACONVERT? technology to existing nickel and PGM smelting complexes.

Jan 1, 2011

Selective Removal of Arsenic from Acid Mine Drainage Containing Ferrous Ion Using Sulfide Precipitation Method

Sep 13, 2010

By L. Yuan, J. H. Rowland, D. Bahrami, R. Thomas

Blasting is the main method of production in many non-coal underground mining operations and produces multiple toxic gases as a result. The Mine Safety and Health Administration (MSHA) requires mine operators to measure the level of toxic gases in mines as frequently as necessary to ensure they are below regulatory safety limits. The current practice uses portable gas monitors to check the concentrations of toxic gases after a fixed post-blast time. This paper studies the application of a gas monitoring system in the return entry of a limestone mine to determine a safe re-entry time. The National Institute for Occupational Safety and Health (NIOSH) conducted such a monitoring program in a limestone mine from September 2016 through May 2018. NIOSH/PMRD (Pittsburgh Mining Research Division) is endeavoring to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions. This study showed that the use of gas monitoring in the return air can be a useful tool at the mine operator’s disposal to detect and reduce the risk of hazardous conditions and also to reliably estimate the re-entry time.

By N. Singh

Merensky Reef is mined extensively within the Bushveld Complex. In previously mined-out areas on the Merensky Reef horizon there are pillars, potholes and remnants that have not been mined. These unmined blocks of ground on the Merensky Reef horizon can influence the mining of the underlying UG2 Reef. The extent of the influence will depend on the size of unmined ground and the middling between the two reef horizons. This paper quantifies the influence of partially extracted Merensky Reef on mining of the UG2 Reef, and aims to provide recommendations for mining strategies, as well as regional and local support to achieve efficient and safe extraction of the UG2 Reef, for various middlings beneath the Merensky Reef horizon. In some cases it was found that relatively shallow UG2 Reef mining could encounter conditions similar to those experienced in deep and ultra-deep mining environments.

Jan 1, 2005

By A Kamkar-Rouhani

The paper describes a mineral potential mapping of gold and other base metals in Mahneshan area, Iran, using geographical information system (GIS), in which, the method of weights of evidence is used to combine spatial data obtained from different sources to make prediction for mineral potential. This is a quantitative tool for mineral resource mapping that can be used to delineate and predict favorable areas for further exploration by using the characteristics of known and similar mineral deposits. In accord with the descriptive model for gold and other base metal deposits, the spatial distribution of 20 known mineral occurrences was used. In addition, digital evidential maps were used in this study. The maps include maps of lithological units, faults and first derivative of total aeromagnetic data, remotely-sensing data of alteration and also geochemical evidential maps produced on the basis of the results of chemical analyses of samples taken from the stream sediments in the area, and analysed for Cu, Pb, Zn, Sb, As, Ag, Au, Ba and Hg elements. The binary maps were produced and then combined with the model of weights of evidence using 20 known mineral occurrences to obtain a final map of the favourable areas for further exploration of gold and other base metals in the study area. The final map is a predictive GIS model of the mineral deposits in the area. An interesting matter about the final predictive GIS model is that the faults are mainly located in favorable areas which possesses the most probability of mineralisation. Therefore, the faults in these areas have priority for further exploration of gold and others base metals.

Jan 1, 2005

By W. J. Verner, J. R. Lucas

Billions of tons of bulk solid materials are processed through our industrial plants each year, and the tonnage is steadily rising. It has been estimated that for every dollar spent in industry as a whole, approxinlately 30 cents is consumed in the handling of bulk solid materials. It is in this category that tremendous savings are possible through the use of improved techniques. Since World War 11, the mining, steel, chemical, and grain industries, among others have made use of increased materials-handling automation in order to gain some of these savings. However, in a chain of automatic operations, every link must be completely reliable, for if there is a single failure, the whole system immediately becomes ineffective. Only too often the weak link in the chain proves to be the flow of bulk solids from bins. To contribute to the fundamental knowledge in this area, a research study has been continuing at The Ohio State University. The principal objective of the investigation has been to study the internal stresses existing in confined bulk solids. LITERATURE SURVEY Literature studies have revealed that many outstanding people have made contributions to the field of bulk solids. For instance, C. F. Jenkin,1 suggested: a. The pressure on a bin wall is not directly proportional to the depth beneath the surface of material in the bin. b. The vertical pressure distribution on the base of a bin is not actually uniform but is a variable. c. Arches form in bins as a result of very small deformations of the material in the bin. This deformation causes a series of gaps to appear, and consequently causes the disappearance of diagonal forces that cannot act across these gaps. The removal of the diagonal forces causes horizontal forces to be introduced which seem to be the chief cause of arching. 11. A. Janssen,4 in 1895 in connection with his experiments on bins, derived a differential equation to describe both the lateral and vertical pressure in bins with vertical sides. This represents a significant contribution to bulk solid theory, and thus its solution is reproduced as follows: L = KV = RW/U' [l-e -U'KY/R] I where L is the lateral pressure of the bulk solid in psf., V is the vertical pressure of the bulk solid in psf., K is the ratio of the lateral pressure to the vertical pressure at any point, R is the hydraulic radius of the bin in feet, W is the density of the bulk solid in lbs. per cubic feet, U' is the coefficient of friction between the stored material and the bin wall, and Y is the head of material above the point in question in feet. In 1903, Jamieson,6 in an elaborate series of experiments on full sized bins measured vertical and lateral pressures by hydraulic diaphragms. He determined many values for mediums of corn, wheat, peas, and flaxseed. In 1951, Caughey, Tooles, and scheer3 measured both lateral and vertical pressure in deep bins by using strain guages on steel bands. Values were calculated for cement, gravel, sand, soy beans, shelled corn

Jan 1, 1961

Up to 19 chemical parameters were studied in flotation pulps in six Australian lead-zinc concentrators with the aim of obtaining a better understanding of the nature of, and changes in, the chemical environment. This paperdiscusses pH, redox potential, and oxygen concentrations, which were all measured continuously.Two plants operated at natural pH in slightly acid circuit and one at natural pH in alkaline circuit, and pH was stable at all these plants. In two plants varying amounts of cement fill were present in mill feed and pHwas variable. At the other plant pH was controlled with soda ash and lime.Redox potentials became more positive as the pulp passed through the plant. The minimum change was 20 mV and the maximum about 250 mV. Potentials tended to be variable at any point early in the circuit, but were more stable later on. In some plants reagent additions had no noticeable effect on redox potentials. However in the two plants operating in acid circuit the redox potential of .zinc rougher feed was markedly affected by changes in copper sulphate addition rate. Sodium sulphite additions had an effect at other plants.Oxygen concentrations in grinding circuits tended to be low (30 per cent of saturation) and very variable. Flotation was usually conducted in pulps at least 90 per cent saturated with oxygen. Addition of sodium sulphite had a marked effect on oxygen content in one plant, but less effect in two others.Statistically significant relationships were found in some plants between pH and redox potential, redox potential and oxygen saturation, and oxygen saturation and pH.Improved control of copper sulphate and sodium sulphite additions could result from applications of this work.

Jan 1, 1970

Preparation of MgO Nano-Particles with Magnesite

Sep 13, 2010

By S. Kitamura

In recent years, the amount of ferritic stainless steel production has increased. However, the rust formation by the salt spray test was pointed out in the past. At the centre of the circular rust zone, pitting corrosion where water-soluble nonmetallic inclusions were embedded was observed. These inclusions originated from the suspended refining slag and consisted of multi-phase oxides and sulphides. By the experiments and thermodynamic consideration of the water-solubility, not only CaO or CaS, but also lime rich calcium-aluminates or calcium-silicates have shown large water-solubility. The composition of oxide phase in the inclusions was almost the same among the samples from molten steel, slab, or cold rolled sheet. On the contrary, CaS was clearly observed around the oxide in the sample of cold rolled sheet, although it was not found in the molten steel or slab samples. The enrichment of sulphur occurred from the desulphurization reaction of the suspended slag particles in the molten steel and also occurred from the diffusion of sulphur to the oxide inclusions during the heating of the slab. The optimization of refining slag composition has lead to produce the ferritic stainless steel without rust formation. Keywords: stainless steel, rust, calcium aluminates, calcium sulphides, water-solubility, refining slag, composition control of inclusions.

By T. Banerjee, D. Felsher, G. Leavoy

"Lake Shore Gold is engaged in commercial gold production at both the Timmins West and Bell Creek mines, located in Timmins, Ontario. Run of mine ore is processed at the Bell Creek mill which consists of a conventional gold mill flow sheet involving crushing, grinding, gravity concentration and carbon-in-leach (CIL) for gold recovery. Since 2009, the operating capacity of the mill has been upgraded from 2000 tpd tonnes per day (tpd) to over 3,000 tpd. The most recent expansion involved the installation of a low aspect ratio SAG mill to replace the secondary crusher. Without operational data on the low aspect mill, combined with a site team that was new to SAG milling, there were many challenges in achieving the target throughput from the circuit. Through the implementation of AwaRE advanced controllers, running in closed loop with PRC fragmentation cameras as well as embedded PARC modules within the Allen Bradley PLC, the site was able to rapidly develop a best operating practise and has been successful in creating a stable and consistent operational environment. The process, lessons learned and eventual solution will be reviewed in this paper.INTRODUCTIONLake Shore Gold is engaged in commercial gold production at both the Timmins West and Bell Creek mines, located in Timmins, Ontario. Run of mine ore is processed at the Bell Creek mill which consists of a conventional gold mill flow sheet involving crushing, grinding, gravity concentration and carbon-in-leach (CIL) for gold recovery. Since 2009, the operating capacity of the mill has been upgraded from 2,000 tpd tonnes per day (tpd) to 3,150 tpd. The most recent expansion involved the installation of a low aspect ratio SAG mill to replace the secondary crusher. This endeavor was split into two phases: the expansion of the back-end (Phase 1) and the front-end (Phase 2) of the mill. Phase 1 of the expansion was completed at the end of 2012 and involved enhancements and capacity addition to the leaching and adsorption circuits, which increased the mill’s capacity to 2,500 tpd. Phase 2 of the expansion commenced at the end of July 2013 and involved the expansion of the crushing and grinding circuits. The expanded front-end of the mill now has a capacity of 5,500 tpd, and processes ore from both Bell Creek and Timmins West mines. The updated flow-sheet, as shown in Figure 1, illustrates the replacement of the two-stage crushing and ball milling circuit with a single stage crusher and a low aspect ratio SAG mill."

Jan 1, 2015

By D. P. Penswick

The Palabora open pit is scheduled to cease operations in 2002. While the ore body continues below the bottom of the final pit shell, the stripping ratio precludes further economic open pit mining. Palabora Mining Company has investigated various means of continuing copper production, and has determined that an underground mine is the best solution. Board approval to commence construction of the mine has been granted and shaft sinking is underway. First production is planned for the year 2000 and full production of 30 000 t/d will be achieved by the end of the year 2002. [ ] Mechanised block caving will be the mining method employed at Palabora. The cave will be initiated by excavating a thin horizontal slice known as the undercut. Removal of the undercut will induce stresses which cause the rockmass overhead to fracture. Fractured rock will gravitate through drawbells to drawpoints on the production level, and be loaded by LHDs for transport to crushers.

Jan 1, 1997

The ore is very 'refractory. It consists essentially of arsenical pyrites, iron pyrites, zinc blende, galena, antimony as sulphide and probably, in combination with galena, as Jamesonite, magnesium, and aluminium silicates with quartz. Some of the oxidized ore, of which there is very little, has a very interesting composition. A specimen shown to me by the ,general.manager, Mr. F. B. Stephens, consisted of hydrated arseniate of iron, orpiment, pyromorphite, lead oxide, with magnesium silicates and quartz. The ore found in the mine with a composition similar to this specimen was valued for gold contents at 60 oz. per ton. This ore is found as a small leader, which runs parallel to the main ore body, at intervals cutting through it.The ore is conveyed from the mine to the reduction works by means of a double road tram line. The mine is situated about rooo feet above the plant on a hill. The grade is so great (about I in 2) that the loaded trucks coming down are able to pullthe empty ones up, thus obviating the necessity of motive power for haulage. All that is necessary is two large grooved pulleys, fixed at the summit of the hilI, and provided with a rope-break for steadying the speed of the trucks down the hilI.

Jan 1, 1903

By Robert Hopler

A blast caused the destruction of a bridge and loaded freight train and the death of three men, near Chattanooga, Tenn., on May 16, 1907. The blast and its disastrous effect has been described by Mr. Hunter McDonald, M. Am. Soc. C. E., in a paper read before the Engineering Association of the South and reprinted in the Proceedings of the Association for April-June, 1907. The excessive damage was so largely due to coincidence and wreckage of the bridge and train so complete that the incident is worthy of notice.

Jan 1, 2008

This paper reviews the current techniques employed in the prediction of subsidence and how they have been applied to partial extraction systems. The method using influence functions to describe the shape of the profile is investigated in detail and has been adopted to model the subsidence over workings in Huntly. It is compared with the profile methods developed in the United Kingdom and found to predict the subsidence profile more accurately than these methods.

Jan 1, 1991

By Kazunori Matsushita, Frank Vespi, Emi Walder, Mitsuo Nozu

During the runway expansion project at the Fort Lauderdale-Hollywood International Airport in Florida (FLL project), therewere complicated geotechnical issues with a number of cavities in the limestone-loose sand mixed ground thatexisted in many areas below the existing ground. Collapsing the cavities and compacting the runway foundation to secure the take-off and landing of aircrafts was a necessary requirement for the project. The Mammoth Vibro-Tamper (MVT) which produces less vibration and noise level, was proposed and accepted as the alternative to the originally specified Deep Dynamic Compaction (DDC) for the runway with its length of 1.5 miles and area of 570,000 square yards. In this report, the shallow compaction effect and reduced ground vibration with the MVT are presented in comparison with the DDC which was utilized on the same project in a different area of the airport. INTRODUCTION MVT was developed by Fudo Tetra Corporation in the 1960’s and has been widely used in Japan (more than 14,400,000 square yards). For example, at the Kansai International airport, a large area including aprons was compacted with the MVT. It is capable of compacting up to approximately 5m in depth by using a heavy steel plate (3m x 3m) and a strong vibrator motor (V-180, 10Hz) on top of the steel thick plate with specified time duration. We were involved in densification work with the MVT at the Fort Lauderdale Airport Project (Figure 1) from June, 2012 to February, 2014. Deep Dynamic Compaction (DDC) was originally specified as the compaction method to secure the relative density over 70% in every 2,000 square yards grids, however, we proposed the application of MVT to reduce the vibration risk and it was accepted as the alternative (Figure 2). The compaction work was completed in February 2014, without causing any delay in regard to the residual settlement due to the high embankment (H=60ft=18m).

Jan 1, 2018

By Michael Rieber

Mineral economics interfaces the mineral sciences and engineering with finance and economics in the analysis of appropriate questions facing the minerals and energy industries. Its practitioners include those trained in the earth sciences; mining, petroleum, and geological engineering; metallurgy and mineral preparation; as well as finance, information systems, economics, and statistics-most usefully in one or more combinations. Allowing for some overlap, three general areas may be identified: evaluation, economic analysis, and resource appraisal. Evaluation begins with mine investment analysis (exemplified by Gentry and O'Neil, 1984) and process costing, for which the STRAMM Handbook (Anon., 1977) provides a well-known basis for mining and beneficiation. But it extends from property appraisal, often used for the determination of taxes and royalties, through the determination and comparison of transport costs (e.g., Richer and Soo, 1977), and to benefit/cost analyses of externalities. Economic analysis, the subject of this section, is displayed in rigor and extent both theoretically and as applied to commodity classes in Vogely (1985), but it is implicit though apparent throughout Lefond (1983). The text edited by Vogely places minerals in their aggregative context with economic growth and trade, proceeds to the theoretical analysis of minerals and their markets, analyzes the structure and performance of the major mineral sectors, and concludes with policy issues: fuel, nonfuel, and environmental. Resource appraisal employs quantitative methods for the estimation of mineral and energy resources. It moves through geologic, geophysical, and geochemical properties to the identification of estimation procedures for mineral endowment and for the economic measure of stocks and flows of specific minerals (Harris, 1984). It can be used to estimate the probable amount of a specific resource remaining in a given region and has been used to project sites in a specific

Jan 1, 2008

By Antoni Kalukiewicz

From 1997 through 2000, a team of Polish experts headed by the author studied the prospects of mining newly discovered emerald deposits in Afghanistan. This article describes the scheme for mechanization of the mining operations, along with improvements made to the ventilation facilities and lighting. The required equipment was flown to Afghanistan and the Afghan miners were trained in machine operation and maintenance.

Jan 1, 2005

By D. Settles, R. Rose, P. L. Dunn

"A new mineral sands operation is being developed in Georgia by Southern Ionics, Inc. (SII). Prevailing mineralogy and certain design constraints required detailed testing and circuit analysis to create a robust separation processes. The floating wet concentrator plant (WCP) and mineral separation plant (MSP) flow sheets were designed based on historical testing information and recent SII test campaigns on various composite feed samples. The flow sheets were finalized through rigorous process and orebody sequence modeling.The process uses traditional physical separation equipment; however a new MT spiral, the MG12, was selected for use on board the WCP for roughing duty. The MG12 spiral is a two-stage, twelve-turn spiral that has been proven to achieve very high recoveries of heavy minerals. The floating plant includes feed desliming operations, a central MT surge bin for optimum spiral circuit feed control and ancillary operations for concentrate and tailings handling. Scrubbed heavy mineral concentrate (HMC) is then transported to the MSP for concentration of the titanium and zirconium bearing mineral fractions.The testing, flowsheet development, and plant design will be described and explained, and a brief summary of the current project status will be given.IntroductionSouthern Ionics Inc. (SII) is a privately held chemical manufacturing company, founded in 1980 by Milton Sundbeck. SII focuses primarily on the sale of specialty and intermediate inorganic chemicals. Core markets include cement and refinery catalysts, molecular sieves, zeolites, pulp and paper, pharmaceuticals, TiO2 and water treatment. SII is built on the four cornerstones of service, quality, technology and delivery with all SII facilities ISO certified and key products used in potable water treatment certified to NSF standards. SII owns and operates its own transportation fleet and is focused on being a low cost producer, committed to safety and the environment."

Jan 1, 2015

By R. A. Hatch

This report summarizes the results of nearly 8 years research on and production of synthetic mica at the Electrotechnical Experiment Station of the Federal Bureau of Mines, Norris, Tenn. This program was undertaken at the request of the United States Department of the Navy and was financed mostly by the Army Signal Corps and the Navy Bureau of Ships through a contract with the Office of Naval Research, The original objectives included fundamental studies of fluor-phlogupite and other fluorine-micas and production of synthetic mica sheets on a pilot-plant scale. The first 3 years of this project were devoted mainly to a search for practical solutions of the many problems involved in designing and constructing a pilot plant for crystallizing fluor-phlogopite mica. The first and most urgent need was a suitable container for the corrosive mica melt. After extensive study, it was concluded that platinum, graphite, high-silica fire clay, and silicon carbide were the most promising refractories for crucibles; but none was perfect. Silicon car¬bide seemed to have the better combination of qualities, combining good corrosion resistance with oxidation resistance.

Jan 1, 1957