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By William Benzon

Bethlehem Steel's Cambria Division coal cleaning and preparation plant, operated by Bethlehem Mines Corp., is located in Cambria County, Pa., about 2 ½ miles southeast of Ebensburg. Here, above ground, is the most modern coal preparation plant in the world. Below the surface is a new coal mine also referred to as "the most modern that could be built today." The preparation plant has a capacity of 1370 tons of clean coal per hr. It serves three Bethlehem mines, Heisley No. 31, Revloc No. 32, and the new Cambria Slope No. 33.

Jan 12, 1965

By M. Savella

The Runruno Gold Project is located on the island of Luzon, approximately 200 km north of Manilla in the Philippines. The mine is a surface mine operation and use the proven BIOX® and carbon in leach processes to recover gold, and the ASTER™ process for detoxification of the CIL residue prior to discharge to the Residue Storage Impoundment (RSI). Work to date has defined a mineral resource of 1.39 million ounces of gold, and the operation will produce 96,700 ounces of gold per annum over a mine life of 10.4 years. The BIOX® circuit is designed to treat 140,000 tpa of concentrate with a design capacity of 404 tpd of concentrate at a design sulphide sulphur grade of 17% S2-. The Runruno project is the first BIOX® plant to implement the Generation III BIOX® design principles. As part of the Generation III BIOX® program Outotec supplied a turnkey, containerised metallurgical laboratory to facilitate the first four stages of the BIOX® and ASTER™ inoculum build up requirements. BIOX® inoculum build-up was started during early January 2015 with 5 litres of stock cultures shipped from South Africa. The BIOX® culture was successfully adapted to concentrate produced from the mini plant during March 2015. The ASTER™ inoculum build-up commenced during early August 2015 utilising 27 litres of ASTER™ bacterial inoculum already adapted to similar process conditions expected during commercial operation. This paper will detail the various stages of inoculum build-up through to commissioning and ramp-up of the BIOX® and ASTER™ Processes at the Runruno Gold Project. The paper will highlight some of the factors affecting the commissioning process as well as the improvements seen through the introduction of the Generation III BIOX® design principles.

Jan 1, 2017

By C. S. Harloff, Frank R. Corwin

THE Nichols Copper Co., associated with the Phelps Dodge Corp. and the Calumet & Arizona Mining Co., has constructed at El Paso, Tex., and is now operating a copper refinery with a yearly capacity of 100,000 tons of anodes. Transportation facilities were perhaps the most important of the considerations that led to the selection of this site. The rapid industrial development of the Middle and Far West has increased the consumption of copper there. The advantage of local refining as against shipping the copper to the Atlantic sea- board is apparent. Copper refined in the Southwest is equally competitive for export shipment, either from the Gulf or the Pacific Coast ports. The tonnage of copper produced in the Southwest not only justifies the construction of this plant, but may warrant considerable expansion in years to come.

Jan 1, 1930

By R. W. Reisinger

An historic underground copper mine in Wyoming is discharging neutral but copper-laden water into a pristine creek. The EPA-deferred site qualifies for reclamation by the Wyoming Abandoned Mine Land (AML) program; restoring the discharge so that the creek can eventually support a trout fishery is the cleanup goal. Hydrological and geochemical investigations underground have suggested two sources of mine water: one clean and the other copper-containing. Results of bench-scale and pilot-scale tests support the viability of using low-cost passive treatment techniques to reduce copper concentrations in the near-freezing mine discharge.

Jan 1, 1998

By James P. Sloss

A PERMANENT assay office is commonly established as part of the general plant equipment of operating gold and silver properties, but during the development stage of a mine, the cost of such an office is usually so assay work must be done elsewhere. In most instances only a few samples will be taken each day, but if the mine is to be developed scientifically, the analyses of those samples will guide further development. Under such circumstances, the time element in assay returns is important, since the lapse between the taking of the samples and the receipt of results may determine the success or failure of a small-mine operator. The following description of fur-

Jan 1, 1935

By C. S. R. Rondestvedt

In February 2010, Teck?s newest Concentrator at Mina Carmen de Andacollo (CDA), Andacollo, Chile was commissioned. The Concentrator is a single line configuration, comprising of one 36 ft diameter x 20 ft long SAG mill driven by an 18,000 hp gearless drive. The SAG mill feeds two ball mills each 25 ft in diameter x 40.5 ft long, each driven by a total of 19,000 hp through dual pinion drives. A series of four phases will be reviewed from operational readiness, mechanical completion, commissioning, and ramp-up. Also, now after 6 months of operation, this paper will review the significant steps taken during ramp-up enabling the announcement of commercial production, in October 2010.

Jan 1, 2012

By C R. Fountain, W R. Cannings

The zinc-lead-silver mineral resource at Lady Loretta ranks amongst the worldÆs richest when measured in terms of in situ metal grades. However, the project remains undeveloped 28 years after its discovery in 1969. The primary obstacle to development has been the fine and complex grain structure of its ores, which make flotation concentration inefficient even with fine grinding. The size and remote location of the deposit have also hindered exploitation. BUKA planned to directly fume the volatile target metals from the ore when it acquired the project. Intensive, post-acquisition modeling showed the innovative processing route to be uneconomic, notwithstanding high metals recovery and low waste content in fume product. Progressive modifications and supplements to the underlying fuming process enhanced economics and resulted in a new mine-to-metal processing route for zinc-lead-silver ores. The proprietary, three-stage BUKA Zinc Process offers technical, economic and environmental advantages. It is expected to find widespread application in the treatment of ores and residues. However, neither continued R&D nor application to Lady LorettaÆs currently delineated resource can be justified under prevailing market conditions. The objectives and results of each step in the process development sequence are outlined with reference to their impact on the commercial viability of the Lady Loretta project.

Jan 1, 1998

By A. Warczok, C. M. Diaz, A. Bergman, T. Utigard, M. Barati

The world wide consumption of energy is steadily increasing and by 2030 it is forecasted to grow by another 50%, leading to mounting political and economic pressures. For any pyrometallurgical operation, it is therefore paramount to investigate and implement methods to decrease the use of energy. In the pyrometallurgical processing of steel, copper, nickel and other high temperature metals, a large amount of energy is lost in hot off-gases, molten slags, mattes and molten metals. Most of this energy is generally lost during the cooling and solidification steps with very little focus on energy recovery or reuse. In this paper we will quantify how much energy is contained in the various slag streams, then review previous attempts and methods employed to recover some of this energy, and finally evaluate some novel technologies that could potentially be employed.

Jan 1, 2011

By B. Arvidson

Computer-controlled machine sorting may, if properly applied, have a dramatic effect on overall economics of a mine operation. Radiometric and photometric sorters have been used for many years and new developments will be reported, such as a sorter for fine particles and a conductivity/magnetic sorter. Application examples with emphasis on precious metals will be given. Economics for some of the projects will be reviewed and discussed. Sorting underground is shown to be particularly attractive, but machine sorting would be profitable in most cases based on savings in transportation and milling/beneficiation costs only.

Jan 1, 1987

By Thomas A. Palmer

Free cyanide has been successfully determined in ground and surface water by isolation using a microdiffusion technique followed by a pyridine-barbituric acid photometric finish. The determinable free cyanide includes hydrocyanic acid, ionic cyanide, and the cyanide of weak complexes such as cadmium, lead, manganese, and zinc cyanide. Complexes of copper, iron, nickel, and silver are sufficiently strong so the dissociation into free cyanide does not occur at the microdiffusion pH 7. Cyanate, sulfide, and thiocyanate do not interfere. Samples containing as little as 0.005 mg/L are successfully analyzed. The relative standard deviation is <10%. Samples stored at pH >I2 in the dark are stable at least three weeks.

Jan 1, 1981

By The Hollinger Mill Staff

ALTHOUGH cylindrical grinding mills have long been used, there is wide divergence of opinion as to what constitute best operating conditions. Questions such as mill diameter, diameter-length ratio, revolutions per minute, type and size of grinding media, volume of charge, circulating load, pulp level, pulp consistency, liner design, and size of feed, have all been given serious consideration by competent scientific investigators as well as by operators. While many laboratory and plant tests have been made that would seem to justify certain definite conclusions, there is a dearth of definite data giving actual results obtained when a grinding mill working between fixed limits is operated at its maximum capacity under varying conditions as to ball load, circulating load, speed, etc. In tests conducted recently at the Hollinger, extending over a period of thirteen months, to determine the best operating conditions for a ball-mill 6 ft. 6 in. diameter inside the liners, some very interesting facts have been ascertained. This paper is presented in the desire to make public the results of these tests and not with the idea that the last word has been spoken in regard to grinding. We feel, however, that these facts justify certain definite conclusions and hope that, by the fullest and frankest criticism and discussion, the essentials necessary for the correct design and operation of grinding mills will become better known.

Jan 1, 1937

By N. Ogbonna, D. G. Dixon

Although heap bioleaching has been recognized as an economic alternative for treating low grade mineral ores, the underlying physical, chemical and biological processes involved are complex. A detailed investigation into the dynamics of heap bioleaching processes has provided much insight into the underlying complexities, and has led to the development of a sophisticated modelling tool - HeapSim. This tool can be of great help in the design and operation of heap bioleaching processes. In this paper, the mathematical model implemented in HeapSim is examined. The model takes into account mineral kinetics, particle level effects, bacterial growth, oxidation and adsorption, gas absorption, pore diffusion, bulk advection, gas balance and heat conservation. Three case studies where the model has been applied are briefly discussed. Computational Analysis in Hydrometallurgy 35th Annual Hydrometallurgy Meeting held in conjunction with the 44th Annual Conference of Metallurgists of CIM Calgary, Alberta, Canada Edited by

Jan 1, 2005

By B. J. Arnold

Coal blending inherently means homogenizing a mixture of coals so that, overall, the properties of the blend meet some specifications for maintaining power plant performance and emission requirements. In common practice, however, coal blending is at best coal mixing. If necessary, more sophisticated blending systems can produce a more homogeneous feed by using accurate weighing devices and on-line coal analyzers coupled with sampling systems. Blending can be accomplished at the mine, on stockpiles, and from bins, bunkers, and silos.

Jan 1, 1994

By Denard Brandt, Isidro Martinez, Greg Baker, Laura Slattery, Teddy French

The Dos Pobres Mine is a copper oxide heap-leach mine located near Safford, Arizona. Mine production is 180,000 tons (163,293 tonnes) per day with a stripping ratio of 2:1. During the startup phase of the mine, the required fragmentation size was easy to achieve as the ore was highly weathered and fractured near the surface. As the mine depth increased, the proper fragmentation size became harder to achieve due to less weathering and different rock types. Because copper recovery increases as crusher product size decreases, achieving the appropriate product size at the crusher is the operating priority.

Jan 1, 2010

By Rustu S. Kalyoncu

A major goal of the Bureau of Mines is to conserve the Nation&apos;s mineral resources by developing improved performance materials. In support of this mission, a survey of the state of the art of chemically bonded refractories has been made, covering the scientific literature, government reports, and patents. This review includes research and development results for phosphate, silicate, oxychloride, oxysulfate, and other bonding agents used in refractories manufacture. A significant finding of the review was that references on bonding mechanisms, bond formation kinetics, and other important process parameters and conditions were few and universally vague. As a result, recommendations are made to expand research efforts to investigate the kinetics and mechanisms of reactions in chemically bonded refractories.

Jan 1, 1982

By L. Adler

A systematic, balanced and inclusive formulation of the vast input data for mine design is presented. Since the quality of this statement severely influences subsquent design it is extremely important to senior mining engineers and the profession-at-large. If unfocussed, chaos can result along with serious ommisions. The basic categories, each a traditional one are: 1) Natural Conditions (geology and geography), 2) Company Capabilities (monetary and managerial), 3) Public Domain (regulations, contracts, good will, etc.) and 4) State of Art (mining engineering professionalism). To further reduce the data additional organizing principles were used: the distinctions of mining (vs. civil) engineering, proceeding from the general to particular, the basic engineering dimensions, and separating dependent from independent variables. The results are a unique and unified corpus, which anticipates the mine design procedure.

Jan 1, 1987

By Don Painter, Nico Sutmoller, Lori M. K. Kahikina, Brian Dorwart

This paper will address the feasibility of using low-density cellular concrete (LDCC) for an annular fill application where project conditions required pumping the LDCC material for distances of up to 16,000 feet. These conditions occurred during construction of the Kaneohe-Kailua Sewer Tunnel in Oahu, Hawaii, between 2014 and 2018. Located on the island of Oahu, Hawaii, this 13-foot-diameter rock tunnel extends for approximately three miles from the Kaneohe Pre-Treatment Facility to the Kailua Regional Wastewater Treatment Plant. The tunnel was built to convey wastewater and provide temporary storage for peak wet weather flows entering the collection system, thereby reducing the potential for uncontrolled discharges. LDCC was chosen for this project partly due to its environmental benefits, which were essential for an application contiguous to the inland marine and coastal waters of the Pacific Ocean. In order to ensure optimal performance characteristics—compressive strength (with a requirement of 300 psi at 56 days), flowability, and light weight—were achieved, extensive testing of various LDCC products and mix designs was completed. The testing measured the initial set time of the LDCC as well as the compressive strength needed to reduce the quantity of grout lifts required for the project.

Jun 13, 2021

By P Swart, A Fletcher, P D. Erskine

Glencore Coal Assets Australia (GCAA) operates five coalmines in Queensland and has rehabilitated thousands of hectares of mined land across these sites. Accordingly, GCAA seeks to continually improve rehabilitation outcomes over time and work towards progressive rehabilitation sign-off. The ultimate test of rehabilitation success is the attainment of an agreed land-use target, whether for biodiversity conservation or some type of agricultural production, and the ability of the rehabilitated landscape to resist degradation and retain desired functions (eg biodiversity protection or grazing productivity). However, success must be based on documented evidence that can demonstrate adequate progress towards rehabilitation targets and is assessed at appropriate intervals. To assist this task, a stepwise decision guide for the GCAA monitoring program was developed to ensure consistent monitoring data is collected across the range of sites. This presentation will discuss some of the processes that were followed to allow GCAA to identify appropriate metrics to assess rehabilitation success efficiently over thousands of hectares.CITATION:Erskine, P, Fletcher, A and Swart, P, 2016. Preparing for progressive mine rehabilitation sign-off in Queensland, in Proceedings Life-of-Mine 2016 Conference, pp 148–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By J Harris, P Kirsch, R LaBouchardiere

æMining + Health in DevelopmentÆ is a project funded by the International Mining for Development Centre (IM4DC, 2012) to develop a centralised database of corporate sustainability initiatives for managing and improving occupational and public health, based on information extracted from social and environmental reports of major mining, oil and gas (MOG) companies. This register of materials has the potential to increase stakeholder awareness of the unique health risks impacting the minerals industry, employees, their families and surrounding communities, as well as to inform stakeholders on global industry approaches to health management.Data and preliminary outcomes from analysis of different MOG corporate sustainability reports on public health and disease management are presented for six African countries (Democratic Republic of Congo, Ghana, Mozambique, Sudan, Tanzania and Zimbabwe) and six Asia-Pacific countries (Indonesia, Mongolia, Pakistan, Papua New Guinea, Philippines and Vietnam).With the minerals industry facing ongoing rapid growth worldwide, including continuous expansion into developing regions, the æMining+Health in DevelopmentÆ project will inform industry, civil society and regulators of current health management practices and programming among the different sectors of the minerals, oil and gas industries and across various regional operations. This baseline information will serve as a resource for minerals industry managers, providing a forum for sharing best practice health management approaches amongst MOG companies.CITATION:LaBouchardiere, R, Harris, J and Kirsch, P, 2012. Mining and health in development - An inventory of global resource industry health initiatives in developing countries, in Proceedings International Mine Management 2012, pp 75-90 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By R. G. Knickerbocker

[The Electromet l&apos;.ur.::ic&apos;l.l LC:tt:n~ to:!&apos;"&apos; of&apos; the BUl~6au 0: M_nes, Boulder City, ..rev. I invest~.f-&apos;8tes th~ r.: nc= I (l.op itr. in tr.e redon around Boulder Dam, and thi" p2pe:.. ., &apos;est.3nttl t rt") d.c-velo !l&apos;\CtltR of n seriAl of studies on "Joron uineral~ mario n.~ t~l"&apos;t f1tn.: ... o]

Jan 1, 1940