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By M. J. Gula, S. S. Xue, E. P. Horwitz, J. T. Harvey

A study has been conducted to control iron in copper electrolyte streams using Eichrom Industries’s new Monophosphonic /sulphonic acid resin. The resin strongly and selectively extracts ferric ion over copper and cobalt from highly acidic copper electrolytes. The resin has a loading capacity of 27 g/L of iron and can be readily regenerated. In addition, the new resin can be easily synthesized using commercially available starting materials. This paper presents the experimental results for iron control in copper electrolyte streams using the new resin and discusses its potential applications to other hydro-metallurgical streams.

Jan 1, 2000

By Yuexin Han, Zehong Wang, Fujia Yu, Wanzhong Yin, Xinchao Wei

Bauxite is the main raw material in alumina and refractory industries. China has plentiful bauxite resources, most of which belong to the diaspore type bauxite with characteristics of high aluminum content, high silicon content and low ratio of alumina and silica (A/S). The resources with A/S 4-7 account for more than 60% of the total resource reserves of bauxite. Therefore improving the A/S through bauxite desilication is the key task of bauxite concentration in China. Normally the grinding fineness of 80-90% - 0.074mm is required in the bauxite flotation process. Thus fine grinding of bauxite ores is necessary, which leads to the high energy consumption. In the meanwhile, bauxite ores are easy to produce slime during grinding processes. The large amount of slime produced in fine grinding greatly worsens the process environment of bauxite flotation, affects the separation performance and results in the loss of metal. Also, fine grinding makes the flotation concentrate difficult to dewater, while the water content in the flotation concentrate must be removed by distillation in the subsequent alumina dissolution process, causing the increase of energy consumption and cost in the production of alumina. In this study, the selective grinding behaviors were examined with Henan Bauxite as feed. Separation of alumina and silica at a coarser grinding fineness was achieved and new route was explored to enhance the desilication in bauxite concentration to improve the A/S of bauxite concentrate.

Jan 1, 2003

By P. Harris

"Comparison of the two most commonly used classes of depressant in the South African platinum industry is complicated by the fact that these polymers induce different effects on the surfaces onto which they adsorb. The use of carboxymethyl cellulose (CMC), which is ionically charged in solution, can lead to increased particle dispersion in addition to the effect of reduced surface hydrophobicity (depression). Guar is typically only slightly charged in solution. Comparison of these two depressants is complicated since it is uncertain whether differences in their action is a result of either depression of dispersion effects.This work investigates the role of dispersion independently to that of depression in the batch flotation of a platinum bearing ore. An inorganic dispersant, sodium hexametaphosphate (NaHMP) was added in parallel to the uncharged guar depressant to simulate the action of depressants with varying degrees of dispersion. By distinguishing between the material recovered by entrainment and the floatable gangue and by including the effects of froth stability it was possible to decouple the effects of dispersion and depression.The results show that both dispersion and depression led to increased grade of the sulphide minerals. Depression leads to a decreased recovery of floatable gangue minerals. Dispersion leads to an increased recovery rate of these minerals and an accompanying decrease in froth stability."

Jan 1, 2003

Jan 1, 1967

By M. Zhang, M. Menabde, R. Middleton

Whilst mine planners almost universally assume deterministic forward commodity prices when undertaking valuations of mining projects, historical data well demonstrates that those prices are quite volatile. This paper seeks to understand and quantify how this forward price uncertainty will impact mining project valuation. This paper will also present a way of computing an upper bound on the expected Net Present Value (NPV) of a mining project given forward commodity price uncertainty.

Jan 1, 2007

Since roof falls in the vicinity of the working face in underground coal mines are a major source of fatalities and injuries in this country's coal mines, it is evident that the present systems of temporary support for use in this working area are ineffective. This seems to be chiefly due to the inconvenience of setting up heavy and awkward devices such as jacks, posts and the like, which also interfere with the movement of men and machines in this critical working area. This program was concerned with defining and testing commercially available materials that could be used as support elements in a more convenient flexible personnel shield. The objectives of this program were to: 1. survey the materials that might provide the support elements of a flexible-material personnel shield for use in underground coal mines and prepare a list of those materials which appear most suitable for use in coal mines. 2. prepare a proposed testing plan for the materials to be selected from the aforementioned list by the Bureau of Mines for further evaluation. The test plan was designed to provide the following information: a. Tensile strength. b. Proportional limit. c. Creep characteristics at room temperature. d. Elastic properties depicted by stress-strain curves. Properties were tested in two directions for woven fabrics. e. Density. f. Resistance to abrasion. g. Resistance to attack by mine atomsphere. h. Resistance to humidity. i. Impact characteristics.

Jan 1, 1972

Newcrest Mining is one of the leading independent gold producers in Australia thanks in large part to its Cadia Valley operations. It is the largest gold and copper producer in New South Wales and one of the largest in Australia. This year Newcrest will expand its operations with a A$545-million expansion in the area. The Cadia Valley is approximately 250 km (155 miles) west of Sydney. The province presently includes the Cadia Hill opencut mine and the Ridgeway underground mine. With a significant mineralized system to the east of Cadia Hill and a mineral resource below Ridgeway, Cadia Valley has the potential to underpin Newcrest?s production for up to 30 years. In 2007, total gold production for the company in-creased to more than 50 t (1.6 million oz) and cash flow increased by 47 percent, according to the company?s annual report. The history of mining in the area dates back to 1851, but Newcrest?s history is young. In 1990, Newcrest commenced activities in the Cadia Valley. In 1992, Cadia Hill was discovered, with the discovery of Cadia East (1995) and Ridgeway (1996) following close behind. In 1998, the Cadia Hill openpit mine was commissioned. In 2002, the Ridgeway underground mine was commissioned and in 2007 the company?s board of directors approved an A$545 million development of the Ridgeway Deeps. The Ridgeway underground mine is located adjacent to Cadia Hill. The Ridgeway orebody has no surface expression but lies approximately 500 m (1,640 ft) below the surface and resembles an inverted teardrop. It measures approximately 450 m (1,476 ft) by 250 m (820 ft) and extends in excess of 850 m (2,788 ft) in depth. Ridgeway is a sublevel caving operation. Crushed ore from underground is delivered by conveyor to a surface stockpile, adjacent to the Ridgeway concentrator. Using similar processes to the adjacent Cadia Hill concentrator, gold and copper are recovered in a conventional flotation circuit to produce a copper concentrate containing elevated gold levels. Ridgeway concentrate is combined with the Cadia Hill concentrate before it is pumped to the filtration plant in

Jan 1, 2008

By W. J. McConnell, C. P. Yaglaglou

"IntroductionThis paper on the kata thermometer is issued by the Bureau of Mines on account of the general interest in this instrument and the fact that it is frequently used in studies of mine ventilation conditions with regard to comfort and health of miners. It has been used in the studies being conducted along this line by the Bureau of Mines on the effects of high temperatures and humidities of air in mine working on the comfort conditions, as well as in studies of atmospheric conditions in mine, railway and vehicular tunnels.The study of the various physiological responses of the human body to different degrees of temperature combined with different percentages of relative humility in still and in moving air, now being conducted at the Pittsburgh experiment station of the bureau in the research laboratory of the American Society of Heating and Ventilating Engineers, cooperating with the Bureau of and the U. S. Public Health Service, presents an added opportunity of investigating the instruments that have been devised to measure atmospheric conditions as they affect the comfort and health of human beings.The ordinary mercury thermometer, as pointed out by Heberden3 almost hundred years ago is a very inadequate instrument for measuring the physiological effects of atmospheric conditions. It merely accounts for that part of the body heat lost by raliation and convection, while as a matter of fact greater part of the body heat resulting from the metabolic process within the body is eliminated by means of evaporation from the surface of the body."

Jan 1, 1924

By Hanlong Liu

The construction process and load-bearing behaviors of Cast-in-place Concrete Thin-wall Pipe Piles are analyzed based on its application on Yan-Tong Expressway project. The low strain test, static load test and field excavation are also carried out. It can be concluded that the new type of pile is convenient to construction with high bearing capacity and reliable quality, which has great potential in practical engineering.

Jan 1, 2006

By Francisco Camus

El proceso de exploración en las campañas mineras es la primera fase del negocio y constituye una de los principales herramientas para su supervivencia, desarrollo y valorización de la industria. En este sentido, el presente texto señala la experiencia de Codelco en la exploración en Chile y su aplicación en Perú. Así, el conocimiento obtenido por Codelco realizado en el norte y centro de Chile, ha generado la formulación de modelos de exploración predictiva durantes los últimos diez años. Dichos modelos incorporaron el conocimiento logrado en el nivel de cada yacimiento individual, los entornos distritales y las franjas metalogénicas donde estos ocurren. En consecuencia, esta experiencia obtenida por Codelco y el reconocimiento de la continuidad en Chile, se extiende en el Perú y se presenta como una oportunidad de interés para el desarrollo de programas de exploración a futuro.

Sep 13, 2001

By R. D. Short

Environmental regulations for noise and air pollution are directly affecting the type of equipment and construction techniques being utilized for pile driving construction using diesel hammers in California and elsewhere. Consequently, the cost of construction is increasing and in some cases, the use of diesel pile hammers has been prohibited. Based on the trend in California and elsewhere in the world, environmental constraints are spreading and becoming more restrictive. The City of Tokyo, Japan, for example has banned the use of diesel hammers. Environmental restrictions on diesel hammers can be satisfied by using modern hammers, clean burning fuels, synthetic lubricants and pre-excavation techniques.

Jan 1, 1989

By W. H. Emens

[This circular is one of a series dealing with tie development and equip¬ment of small and medium size mines, and with the costs of such work prior to productive operation. The preparation and publication of these papers by the Bureau off Mines has been made possible through the cooperation of various min¬ing and development companies. The bureau of Mines has published a series of circulars dealing with min¬ing methods and costs at a large number of producing nines in the United States, Canada, Mexico, an, other countries. Unit costs of development work, shaft sinking, (rifting, crosscutting, tunneling, and raising are usually much higher in the preliminary development of a property than during its productive life.]

Jan 1, 1933

By Minggao Qian, Jialin Xu, Wenqi Lai, Weibin Zhu

This article advances an innovative concept explaining the connotation and technical system of "green" mining. The important theoretical foundations of "green" mining are the distribution and development characteristics of joints, fractures and bed separations, and the seepage and flow behavior of methane and water in the broken rock strata following coal mining. The main focus of "green" mining technique includes water-preservation in mining areas, coal mining under buildings with bed separation spaces grouted to retard surface subsidence, partial extraction and backfill mining, simultaneous extraction of coal and coal-bed methane, coal roadway supporting and underground disposal of rock waste, underground coal gasification, etc.

Jan 1, 2005

Nautilus Minerals and Neptune Minerals are betting that the next great metals rush will take place more than 1,500 m (5,000 ft) below the sea. Nautilus is the first company to commercially explore the ocean floor for gold and copper seafloor massive sulfide (SMS) deposits. Its main focus is the Solwara 1 Project, a polymetallic copper, gold, zinc, silver deposit that is under 1,600 m (5,200 ft) of water off the coast of Papua New Guinea in the western Pacific Oceans? Rim of Fire. Nautilus Minerals, in a joint venture with Placer Dome (now Barrick Gold), began its exploration of what would become the Solwara 1 area in 2005 with side scan sonar and dredge sampling. The dredge and grab sampling confirmed the grade tenor of earlier sampling by scientific research programs. The 45 dredge samples aver-aged 10.8 percent copper, 3.7 percent zinc, 224 g/t (6.5 oz/st) silver and 13.7 g/t (0.4 oz/st) gold. Nautilus has since staked out more than 300,000 km2 (115,800 sq miles) of tenement licenses and exploration applications in the waters off Papua New Guinea, Fiji, New Zealand, Tonga and the Solomon Islands. That is an area about the same size of the United Kingdom. Interest in Nautilus and its projects has grown tremendously since its inception. The company is now listed on the Toronto Stock Exchange. It has raised more than $300 million and spent more than $23 million on exploration. The company has gained the backing of mining majors such as Teck Cominco, Epion, Anglo American and Barrick Gold. It is positioned to become an emerging producer in 2010. Teck Cominco recently agreed to exercise share purchase warrants to acquire three million additional common shares of Nautilus at a price of US$15 million. This will take Teck Cominco?s shareholding to approximately 7.2 percent of the issued shares. Teck Cominco will conduct and manage a ship-based exploration program that will run in addition to the exploration that was already planned for 2008.

Jan 1, 2008

By Don Novotny, Dana Spencer

In this workshop our intent is quite simple; that is that we will introduce a relatively new technology that may have applications in blasting applications. This technology is the laser initiation of explosives. This workshop course is not intended to suggest ways in which specific blasting problems can be resolved. That is the purview of experts within each of your fields.

Jan 1, 1994

By R. J. Folic

Investigations of the vibrations of a pile in soil are performed on a dynamic model in the form of a prismatic bar of finite axial and flexural stifnesses with a discrete mass at its free end representing the cap. The soil is represented by a system of springs of constant and variable stiffnesses. Oscillation differential equations are derived by means of the Hamiltonian principle for non-conservative systems. The problem is reduced to a coupled system of two non-linear partial differential equations with corresponding initial-boundary conditions. Frequency equations of longitudinal and lateral linearized equations are formed. The paper determines natural frequenc­ies and oscillation modes. It separately examines longitudinal vibrations excitated by a hermonic force acting upon the pile cap, and lateral vibrations excitated by an impulse acting upon the cap. The results of the numerical processing are presented in respective diagrams in dimensionless form.

Jan 1, 2010

By Ben L. Seegmiller

INTRODUCTION Site characterization using oriented borehole core is the subject of this paper. Borehole core is a standard source of data for rock mechanics investigations. Oriented borehole core provides data whereby the geometric orientation of various geologic discontinuities (faults, joints, bedding, etc.) may be determined. The orientation and strength characteristics of discontinuities are important in many engineering investigations and in particular, in slope stability analyses. In heavily vegetated or soil covered situations, oriented borehole core may provide the only means of assessing the subsurface planes of weakness which characterize the site. The purpose of this paper is to briefly describe various methods or orienting core, core characteristics which may be logged and the methods of processing and using the data for site characterization.

Jan 1, 1977

By N. Katsikaros, A. Lewis-Gray, P. Richards

"To optimize gold recovery in complex leach-to-electrowinning processes, Gekko Systems developed the Gekko resin exchange column (G-REX) as an intermediate step, using a highly gold-selective resin to isolate contaminant metals. The AuRIX®100 resin produced by Purolite is licensed exclusively to Gekko, with the G-REX column designed specifically for this resin. Operational experience has been gained at the Castlemaine Goldfields Ballarat gold mine. In near-continuous operation since 2008, the Ballarat plant treats unclarified concentrate leach solution. The extension of this technology to higher throughputs and more complex chemistry is discussed.RÉSUMÉ Afin d’optimiser la récupération de l’or dans des procédés complexes impliquant la lixiviation suivie de l’extraction électrolytique, Gekko Systems a développé la colonne Gekko de résines échangeuses d’ions (G-REX) comme étape intermédiaire, à l’aide d’une résine hautement sélective pour la récupération de l’or qui permet d’isoler les métaux contaminants. Gekko détient la licence exclusive pour la résine AuRIX®100 produite par Purolite, et la colonne G-REX a été spécifiquement conçue pour cette résine. C’est à la mine d’or Ballarat de Castlemaine Goldfields que l’expérience opérationnelle a été acquise. L’usine de Ballarat, en exploitation quasi-continue depuis 2008, traite une solution concentrée non clarifiée de lixiviation. L’extension de cette technologie à des capacités supérieures et à une chimie plus complexe est examinée."

Jan 1, 2017

Reason Analysis of Impurity Containing and Technology Discussion of Quality Improvement for Low-Quality Iron Concentrate

Sep 13, 2010

Jan 1, 1967