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By Jake Hutchison, Wade Hutchison

The opposition to the project has risen as a result of some political pressures and from public perceptions about the project’s necessity and its impact on the neighborhood. As a result of this controversy, the Underground Conservation Hall was quickly termed “Bredesen’s Bunker” by the Media. Close exposures for blasting, required by the Conservation Hall construction project, have been regulated by specifications that regulate seismic monitoring, pre-blast and post-blast inspections. Planned blasting for the project included blasting to a depth of 30 feet (9.14 meters) within 35 feet (10.67 meters) of the front of the newly renovated Tennessee Executive Residence. Excavation for the project found more competent rock at higher elevations than identified in test drilling which required blasting within 2 feet (0.61 meters) of the side of the Residence.

Jan 1, 2009

By Q. C. Reynolds

Keywords: Pyrometallurgy, plant, photography, GIS, satellite images, Google Earth Google Earth is a piece of software able to display an interactive three-dimensional map of the world, combining aerial and satellite photography with maps, terrain, and user-generated geographical information systems (GIS). Many structural features of the planet, both natural and man-made, are of great interest to the mining and metallurgy field, and in this paper a study is made of the current state of the art of data accessible by Google Earth.

Jan 1, 2006

By Valentín Pamo

El presente trabajo describe los procesos y equipos que permiten la extracción de metales preciosos de la refinería de Ilo en condiciones agresivas, obligando a investigar materiales resistentes a la corrosión. Asimismo, se presentan alternativas que aseguren la continuidad de las operaciones en el proceso productivo de dicha refinería.

Sep 9, 2007

By H. H. Murray

The largest reserves of palygorskite in the world are located in Anhui and Jiangsu Provinces in East Central China. The deposits are Middle Miocene in age and range from 3 to 6 m in thickness. The deposits are the alteration product of basaltic volcanic ash. The Chinese Geological Survey estimates the palygorskite reserves are in excess of 200 million tons. The elongate particle shape results in unique colloidal properties. Large quantities are exported to Japan, Taiwan, Southeast Asia, New Zealand, Australia, and West and Gulf Coasts of the United States. The markets include agricultural carriers, paint, joint tape compounds, animal feed binders, catalyst support, drilling muds, and suspending agents for chemicals, pharmaceuticals, and medicines. The viscosity is high and the quartz content is generally 5% or less.

Jan 1, 2009

By G. A. Bezuidenhout, J. P. T. Kapusta, D. K. Chibwe

"Peirce-Smith converters (PSCs) are extensively used in the copper, nickel, and platinum group metals industries. The typical converting operation involves lateral purging of air into molten matte through a bank of tuyeres. This blowing operation occurs at low pressure from the blowers, resulting in a bubbling regime that is considered inefficient from both a process and an energy utilization perspective. Inherent drawbacks also include recurrent tuyere blockage, tuyere punching, and low oxygen efficiency.Western Platinum embarked on a full-scale industrial evaluation of generating a jetting regime by using sonic injection. Prior to industrialscale tests, a numerical assessment to ascertain the feasibility of implementing sonic injection into a PSC was conducted. The work included flow characterization at high-pressure injection achieving sonic velocity at the tuyere exit. The 2D and 3D simulations of the three-phase system were carried out using the volume of fluid method together with the RKE turbulence model to account for the multiphase and turbulent nature of the flow.This paper discusses the key findings in understanding plume extension, velocity distribution, shear wall stress analysis, and phase distribution characteristics in the system. Plant trials are also discussed with reference to the commercial aspects of a full-scale implementation of sonic injection in the smelter."

Jan 1, 2015

By J. M. Ekenes

New approaches that increase hydrometallurgical recovery from refractory minerals in below-mill-cut-off-grade sulfide copper ore can add significant value, improve profitability and increase ore reserves. This paper describes the development and implementation of an engineered heap (EH) approach to leaching low-grade, chalcopyrite-bearing ore at Freeport-McMoRan?s mine in Morenci, Arizona. The technical evolution of the engineered heap concept is described together with the challenges and benefits following implementation.

Jan 1, 2012

THE following short paper on the Blair Athol coal-field will no doubt have a twofold interest to members from the fact that its main seam, known as the "Big Seam" of a maximum thickness of 91 ft without a band, is unique, being probably the thickestseam of high-grade clean coal yet known, and also because of the interesting problem it presents the colliery engineer-viz., which system of mining is the best to secure the highest economical extraction.Location - Blair Athol is a mining township in Central Queensland, situated at an altitude of about 1100 ft. above sea-level at the end of a branch railway line 74, miles from Emerald, on the Main Central Western line, and 240 miles by rail from Rockhampton.Geology - The coal-measures appear to lie in a shallow basin of about four or five square miles in area, surrounded on all sides by slates and schists, which are overlaid oh three sides by alluvial deposits of up to 150 ft. in thickness, and on the fourth by a thick basalt bed, as yet unproved, some miles beyond which the auriferous slates outcrop. These alluvial deposits have been largely worked in years past and gave high gold returns, the chief diggings being Clermont and Macdonald's Flats in the south, the Springs and Black Ridge in the north-east, and Yankee Creek and others on the west. The surface of the coal-fields may be described as unbroken, but undulating, with gentle southerly dip, the watercourses opening out into wide flats. The absence of creeks or deep gullies accounts for no outcrops being visible on the surface, and the coal-measures...

Jan 1, 1918

By C Simpson

The Pilbara region of Western Australia is well known for its abundant exports of hematite-goethite deposits, which have been mined and exported since the 1960s. Magnetite has also been mined in Australia throughout this period, although historically of much lower production volumes (WA Iron Ore profile, 2016). Magnetite offers a source supply of material >66 per cent iron grade product, which is used as premium feed (predominantly pellets) to blast furnaces or specialised steel mills.The Iron Bridge project area contains outcropping magnetite and hematite banded iron formation (BIF), which within the region was recognised as having potential to host economic mineralisation during the 1960s. Development within the project area, however, did not commence until Fortescue Metals Group acquired the tenements based on a 2004 agreement, formed a joint venture with interested groups and then initiated an assessment for magnetite (rather than hematite) mining potential. The combined deposits now have an identified large mineral resource inventory, with test work demonstrating they are able to produce a magnetite concentrate of greater than 66 per cent Fe over an extended mine life. This concentrate would be suitable for forming pellets or feed for direct reduced iron products.The deposits form a singular orebody, approximately 12 km in length by 1 km in width and extending to depths beyond 600 m. The four main deposits are geographically separate and have subtle mineralogical differences, thought driven by the degree of deformation and alteration within each area.Definition of the stratigraphy, structure and key mineralogy of the deposits has been carried out through several stages of exploration and project development. This has also included recent mining and processing of more than 1 Mt of feed material to an on-site processing facility. This demonstrated at a production scale that dry plus wet processing techniques can efficiently separate the magnetite from the gangue minerals to form a suitable (marketable) product.Geometallurgical classification of the host stratigraphy has been carried out from analysing the high volume of quantitative data available for this deposit. This has allowed definition of mappable units within the fresh BIF to be used as a driver in mine scheduling, delivering optimal feed to the processing plant.Construction of mine and processing facilities is expected to commence once all technical risks have been addressed, market conditions are deemed appropriate and approval is given by the joint venture partners.CITATION:Simpson, C, 2017. The Iron Bridge magnetite deposits, in Proceedings Iron Ore 2017, pp 287–294 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By I. P. Barbosa, P. S. M. Soares, I. O. C. Masson

"Permanent magnets have been applied extensively to several electronic products such as printers, TV sets, microphones, microcomputers and headphones, presently manufactured in large scale by industrial economies. Sm-Co alloys represent about 20% of the world market for permanent magnets and their industrial processors generate 20-30% of magnetic scraps which can be recycled. This paper discusses a process route to recycle SmCo5 using acid treatment, solvent extraction of Sm and electrowinning of Co. The results confirm the feasibility of the alternative proposed. Basic operational variables are suggested as guidelines to design a plant for recycling magnetic scraps.The use of hydrometallurgical processes to recycle scraps from the industry of permanent magnets has been suggested in some recent papers related to recycling of metallic alloys [ 1 ]. These research efforts might be understood as a worldwide tendency towards the development of self sustainable metallurgical processes which mean the reduction of environmental impacts.CETEM -Center for Mineral Technology leads in Brazil several research programs concerning recycling and treatment of industrial residues. The work on samarium purification and concentration by solvent extraction, producing also a solution of cobalt sulfate as partially reported here is one of these programs. Previous results related to the sulfuric acid digestion of SmCo5 are presented somewhere else [2]"

Jan 1, 1997

By Jim Steding

L.G. Barcus and Sons, Inc. recently completed a three-phase project for the expansion of Presbyterian Hospital in Albuquerque, New Mexico for McCarthy Construction Co., the Construction Manager for the project. It was a challenge that allowed Barcus to demonstrate many of it's strengths. Safety of people and property, restricted access, low headroom conditions, extensive planning to maintain hospital operations and a tight schedule were all key elements affecting the successful installation of the Augered Cast-In-Place Piles. Phase I began with installing and performing a 450-ton pile load test on an 18-inch diameter Augerpile 65 ft long. The load test was installed and performed directly in front of the Emergency Room entrance. Space was limited and the E.R. had to remain open with uninterrupted ambulance access. The results of the load test were outstanding. In fact the test pile performed so well that some of the job piles were shortened from 75 ft long to 65 ft long. [ ]

Jan 1, 2003

GOLD has played a part in the development of Australia. The total yield exceeds SIX hundred million pounds sterling, while the glamour of gold-mining and the unfailing demand for the product have enhanced its influence. The production is still considerable, but the yield is less than one-quarter of that twenty years previously, while the number of men employed has dropped from 70,000 to 11,000. Not only has there been a marked decline in production, but it is anticipated that thisdecline will continue, and continue more markedly. It is therefore desirable to ascertain the causes of the decline and inquire into means for diminishing or preventing it.The problem under discussion is far from being only local. Finlay states: The grand feature of the history of the business has been the progress of an economic cycle unfavourable to gold milling. The USA yield fell from $101,000,000 to $44,000,000.South Afriea has for some time produced one-half of the world's gold; yet in the Mining and Scientific Press of 11th February, IH22, General Smuts is quoted as saying that if the premium disappeared entirely 24 out of 34 mines would shut down. The solution, however, might be either general eg, a great advance in the metallurgy of gold; or local eg, a bonus; but before discussing any of the proposed solutions it will be advantageous to review the situation.STATISTICS OF THE PAST AND PRESENT PRODUCTION OF THE WORLD AND OF AUSTRALIAThe inquirer soon finds that there is a good deal of uncertainty, and that much care is needed in collating figures. In some cases a considerable part of the output is not officially reported, and returns...

Jan 1, 1924

By K. Coleman, C. Visser, N. Selby, X. W. Pan, T. Letwaba

A prototype weightometer soft sensor is under development at DebTech, De Beers in partnership with Venetia Mine. Its main function consists of an online data source; data validation; dynamic weightometer models; online detection of weightometer failure; alarming and replacing a weightometer when it fails. 31 dynamic models have been developed. All models with R2>= 85%are accepted as good models and they generally have satisfactory results with a daily error of less than 8% within 90% confidence level. By using those models, a set of soft sensors can be set up to cover all weightometers in the entire processes starting from primary crushing to the stock piles of dense medium separation (DMS). Some practical issues and concerns on model development are discussed, including data collection, data analysis, data pre-processing, variable selection, time delay, model training and model validation. When deploying the weightometer soft sensor system, the potential benefits could include: reduction in plant downtime; reduction in unplanned maintenance and even replacement of non-critical weightometers, particularly where nuclear weightometers are used. Keywords: soft sensor, weightometer, dynamic modelling, neural network modelling

Jan 1, 2003

By C. J. Kirkland

For two thousand years and more, we insular Britons have been grateful for the existence of the narrow strip of water that separates us from mainland Europe. It has given us a sense of security against invaders, though it has been breached many times. The first recorded serious consideration of a fixed crossing of the English Channel was in around 1802, when it was suggested to Napoleon I. The motive was not entirely peaceable and the British Navy, who saw themselves as defenders of our shores, were decidedly unenthusiastic A whole series of imaginative schemes were proposed in the course of the nineteenth century, embracing viaducts, immersed tubes, artificial islands as resting places for the horses which were to draw carriages, as well as mechanically bored tunnels. The first Channel Tunnel Company was formed in 1872, and an application for permission to construct a tunnel was made to the British parliament. A Colonel Beaumont, of the Corps of Royal Engineers designed and constructed a machine which, in around 1882, bored over a mile of tunnel out to sea from Britain which exists to this day.

Jan 1, 1991

By Nathaniel Arbiter

Flotation’s earliest patent was issued in 1860. However, the process was first applied commercially in Australia until 1904, and in Montana in 1911. Major advances followed both in reagent treatment and in cell design, with resulting process improvements. Mechanical cells have seen the widest use and with the major increases in plant capacities (Fig. 1) their volumes have also increased (Fig. 2). In 1991, the principal use for the process was to produce copper concentrates for smelting. It was applied to 243 Mt (268 million st) of copper ore. The total of all ores floated that year was 426 Mt (470million st). In 1997, US mines produced 257 Mt (284 million st) of copper ores for flotation, yielding1.75 Mt (1.94 million st) of copper.

Jan 1, 2000

By Prosser A. P

The conditions under which vanadium is rendered insoluble by silica in the alkali-roast process have been investigated starting with both slag and reagent-grade materials. The inert phase is a glass formed slowlyfrom soluble NaV03 produced at lower temperatures. It contains approximately 30 per cent V in a partly reduced state; iron is not a principal component. Some of the vanadium in the inert phase is slowly returned to a soluble form by heating in an oxidizing atmosphere below the temperature at which the glass is formed (750°C). As the reaction leading to the required, soluble form of vanadium is also slow between 600 and 750° optimization and control of the temperature profile and atmosphere in the furnace, and the residence time of the solids, are necessary to ensure high vanadium extraction during subsequent leaching.

Jan 1, 1976

By M. Ganster, H. Krenn

The mission of the project is the fast and cost-effective rehabilitation of decommissioned lignite mining and coal upgrading facilities. This is necessary to ensure the successful future utilization of these sites. On the one hand, for founding new industrial and commercial facilities and on the other hand for touristic activities.

Jan 1, 2013

A short account is given of the theory and practice of determining the true U3O8 content of ore samples by the determination of the beta and gamma activities separately, using the method of Eichholz and his associates.It is shown that, despite the variation of sample activity without change in U3O8 content, the true U3O8 value can still be found.Thorium can be determined simultaneously if this element is also present.

Jan 1, 1957

By D Gelling

Mineral sands dry plants consist of a large number of repetitive unit operations with significant transport delays, in the form of stream pipes, conveyors and elevators. As part of the P255 mineral sands sponsorship and using the JKMRC developed conductor/non-conductor (CNC) gauges, control loops have been implemented at the multi-duty dry plant of Cable Sands Limited at Bunbury. This paper describes the loops for kV control on a rougher high tension roll machines (HTR). The options available are product grade control and ratio control using the JKMRC CNC gauges, which measure the percent conductors in a stream. The purpose of control is to stabilise the circuit operation against disturbances such as atmospheric and feed disturbances.

Jan 1, 2001

The Significance of Internal Recycle in Froth Flotation

Sep 13, 2010

By Xiangxi Wu

Longwall and continuous mining are prevalent methods employed by Chinese underground coal operations. The main ground control challenges include roof skin deformation, roof collapse, and outbursts of coal, gas, and water. Microseismic monitoring provides valuable information on rockmass behavior and fracture propagation caused by stress redistribution, active geological structures, or gas build up within the coal strata and the surrounding rockmass. Collecting and assessing seismic data has proven to be an instructive tool for engineers to better assess ground conditions and mitigate seismic hazards associated with mining. The development of intrinsically safe and explosion proof certified seismic monitoring equipment has revolutionized China?s underground coal mines. The use of this technology allows for the optimization of gas drainage at an increased rate of two at a 50% higher purity without any increase in drilling costs. Microseismic monitoring can also be used in identifying seismically active faults and shear zones. This information can be used to assess and revise mining strategies to improve safety and ground stability.

Jan 1, 2012