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By Chris Twigge-Molecey

Demand for metals will continue to grow as global population numbers and prosperity levels steadily increase. Consequently, there will continue to be a need to design and construct new metallurgical plants. Business success in general requires projects to be financially successful and return appropriate value to their owners. However, in the metals industry, private and public sector financing sources have become very sensitive to the perceived inability of projects to contain costs and meet other business objectives. Thus, the capital for projects has become more difficult and expensive to obtain. It is instructive to note that Ernst and Young (2011) identified that: “Delivery of predictable project results bestows competitive advantage and market confidence to those corporations who successfully instill this discipline”. The implication for future projects is that they must be systematically developed to minimize perceived risks—and more importantly—to demonstrate that the risks are managed to achieve the business case. Then, provided that the project has been developed in a well-structured way, project success can again be defined as a project with: a final cost within 10% of the budget approved at the end of FEL3, when the project is properly defined and the permit conditions are agreed upon; a start-up date within three months of the definitive, scheduled startup date; production levels at 85% of design capacity within a year of starting commercial operation; production meeting the target environmental restrictions; and with zero lost time accidents during construction and startup. The plant design is one of many integrated activities required to achieve these objectives. This book represents a valuable link between the existing engineering literature that encompasses a wide range of engineering fundamental textbooks and design manuals and the project management literature such as the Project Management Body of Knowledge, or PMBOK® (Project Management Institute, 2014). It is evident throughout this book, that the design team is a small but essential part of a much larger project team comprising the project management, construction management, and construction contractor staff. Design activities must be regarded and managed as part of the integrated whole, with two fundamental links throughout the design process:

Jan 1, 2015

By M. Zaske, E. R. Mortensen

"As mine operators continuously look for ways to improve functionality and increase the capacity of their facilities, existing process equipment is often pushed to and past its designed limitations. As a result, equipment manufacturers are asked for economical solutions to meet redefined processing needs. Newmont Mining in Nevada was faced with such a need in its carbon-in-leach (CIL) train. In a collaborative effort between Newmont and Derrick Corp., tests were conceived to assess the viability of drop-in replacement screens using a three-dimensional screen panel. The synthetic pyramid screen panel was designed to increase flux while maintaining the existing equipment footprint. The test is the end result of an ongoing research and development project that Derrick undertook in an effort to refine and upgrade its urethane screening media. The application of this new screening media is presented for this CIL application along with future plans to implement the technology in trash, safety, carbon dewatering, carbon sizing and other scalping applications.In spring 2014, Process Machinery Associates (PMA), Derrick’s local area representative, met with Newmont to discuss the operation of the in tank screens in the CIL train at Twin Creeks, near Golconda, NV. The process was originally designed for about 12+ kt/d (13,000+ stpd) but the throughput has been steadily rising since the plant was commissioned. Newmont now requires 14.5 kt/d (16,000 stpd) to be processed. The original screens were running at their maximum capacity, and Newmont required additional screening capacity to continue the upward trend in production.Physical separation by use of screening is one of mineral processing’s oldest methods. Screening media can be prone to blinding and pegging, and the necessary support structures required for finer apertures result in smaller open areas. Therefore, more screening area generally requires larger panels and, thus, larger machines, screening media that does not blind or a combination of both.In an effort to avoid larger machines, Derrick had been working on a revolutionary threedimensional panel that would add nonblinding screen area in the same footprint of an existing machine. Alpha testing of the new screen panels began at Newmont Mill 2/5 in July of 2013. It was still occurring when PMA approached Twin Creeks about beta testing a refined machine and pyramid panel. After presenting the initial results, Twin Creeks determined that an upgraded machine and pyramid panels would be a possible solution to meet production needs. The testing of a machine eliminated the risk of capital costs to Newmont and provided Derrick the opportunity to obtain additional data."

Jan 1, 2015

By S. Ianos, C. Vibert

Type and shape of large dams founded on rock depend upon the expected deformation of their foundation. Their design consequently requires the assessment of the deformability of the rock mass at large scale. Seismic refraction, laboratory tests on rock samples and empirical formulas can provide an order of magnitude of the deformation modulus, with a limited degree of reliability. Direct in-situ measurement of the deformability of a volume of rock is therefore preferred, which integrate the effect of discontinuities, such as plate loading tests, dilatometric tests, etc. The authors have been compiling results obtained by in-situ deformability tests on a number of dam sites, including the Scarabée (“Petite Sismique”) method. This last method consists in thoroughly analysing the shape of seismic wave forms transmitted through the rock mass. It has been used since now more than 40 years over a large number of dam foundations, and has proved to provide a satisfactory assessment of the static deformation modulus. After comparing the results obtained from different methods on six dam sites, the Authors conclude that their reliability closely depends upon the size of the loading device in relation to the spacing of the discontinuities. Attempts to correlate results from different types of in-situ loading tests reveal difficult, because closely depending upon local geotechnical conditions at test location. Plate jacking tests appear to be the most reliable, because involving a relatively large volume of rock. On the other hand, the Scarabée method (“Petite Sismique”) allows a rapid assessment of the deformation characteristics of the rock mass at large scale, and has been found to provide values generally in agreement with those from plate loading tests, while dilatometric or flat-jack tests were found too dependent upon local conditions. The Authors conclude that preference should be given first to the Scarabée method, which uses light equipment and is quickly performed, together with an accurate geological and geotechnical assessment for interpretation. In a second stage, Scarabée shall be complemented by adequately performed plate jacking tests in selected locations, in order to cross-check results and refine the assessment. The general accordance between the results of the two methods, which both can integrate anisotropy of rock masses, justifies this statement.

Jan 1, 2015

By D. M. Richards

"IntroductionThe Highland Valley Copper partnership was formed in July 1986 as a logical result of a mine with a large ore reserve but a small mill, and a mine with a large, modern mill but dwindling ore reserves. The original partnership of Cominco and Rio Algom was expanded in January 1988 to include Highmont Mining Company. During 1988/89 the Highmont mill was moved 7.5 km to adjoin the Lornex mill, becoming the Highland mill in the process, with a nominal capacity of 130 000 tonnes per day.The mine is located near the town of Logan Lake, 220 km northeast of Vancouver, British Columbia and 55 km southwest of Kamloops. The map in Figure 1 shows the general area. Kamloops is a major service centre and is served by two railways, two major roads and a regional airport. The mine site is situated between 1200 m and 1600 m above sea level on the Thompson Plateau. Principle activities in the area, in addition to mining, are cattle ranching and forestry. Ore reserves at the beginning of 1996 totaled 533 million tonnes at a grade of 0.42% copper and 0.008% molybdenum. Ore is mined from two pits — Valley, 3 km northwest of the mill; and Lornex, 1 km southwest of the mill. With 78% of the reserves, the Valley pit is the focus of activity.In order for Highland Valley Copper to remain competitive with a very low grade ore reserve, it has been necessary throughout the mine’s life for new technologies to be embraced as they become available. These have included such diverse technologies as in-pit crushing and conveying, large mechanical drive trucks, computerized truck dispatch and oneman survey instruments. During the next few years, it is planned to introduce two further technologies that are relatively new to both the world at large and the mining industry in particular. These are namely Global Positioning Systems (GPS) and Geographical Information Systems (GIS), both of which are expected to have a major impact on the way mining is carried out in the years to come."

Jan 1, 1997

By James V. Thompson

ENGINEERS from industrialized countries are frequently called upon to examine mining operations in primitive areas and make recommendations regarding mechanization and modernization. They often set forth with self-confidence, knowing full well that all that is needed is their experience and several shiploads of mining machinery, and at times they mentally provide the answers before the problems have been clearly stated. In primitive areas it is absolutely essential that the examining engineer spend enough time at the site to acquire a thorough understanding of what is being done now and why it is done the way it is. The objective here is to state in simple terms some of the problems that may be encountered, in- as much as solutions, if they can be found at all, will differ with each experience.

Jan 8, 1958

By G. H. Lewis

This work was completed in a 440 KW pilot-scale combustor in preparation for a 50,000 Kg/hr industrial steam boiler limestone injection test program. The main objectives of the work were to: (1) identify the variables which affect sulfur capture, (2) determine the maximum sulfur removal, and (3) determine the effect of limestone addition on furnace operability and heat transfer. The variables which were identified as being important in sulfur capture were: Ca/S molar ratio, flue gas temperature at the limestone injection location, and limestone particle residence time. The maximum sulfur dioxide removal was 72%. The addition of limestone increased the particle deposition rate in the combustor; however, all deposits were easily removed by an air lance.

Jan 1, 1985

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By A. J. Monhemius

This paper reviews the history of modern iron-control processes in hydrometallurgy. Attention is paid to processes developed in the electrolytic zinc industry for removal of iron from zinc sulfate leach liquors and the problems faced by the industry in the safe disposal of the iron residues produced by these processes. Past lessons learned are projected onto current efforts to develop hydrometallurgical processes for treatment of copper sulfide concentrates. It is argued that any attempt to create a \u201chydrometallurgical copper smelter\u201d will fail, unless methods are developed that can recover iron in a form that can be directly used by the steel or pigment industries.

Jan 1, 2017

The principal activities of the Bureau of Mines Explosives Research Center from July 1, 1962, to June 30, 1963, are described briefly in part 1. Part 2 gives short abstracts of publications that appeared during fiscal year 1963; in general, the research reported in these publications antedates the report period.

Jan 1, 1965

By A. L. Engel

Simple treatment methods, employing the least possible equipment, can sometimes be established for marginal ores and economical results achieved. In continuation of a long-established part of the hydrometallurgical and ore-dressing program of the Reno Station of the Bureau of Mines, typical ores from newly discovered or recently explored mining districts have been investigated. The purpose of such investigations is to encourage the search for and development of mineral resources and particularly to assist in the economical exploitation of low-grade and marginal ores, as well as the conservation and recovery of values in products from former operations that were discarded because of past inability to treat them economically. Several of these investigations have been limited to preliminary tests of samples from prospecting operations, whereas some involved samples of old dumps or tailings piles. The test, work in these cases was not extensive enough to warrant publication as individual reports, but is of considerable interest inasmuch as it indicates the possibilities as well as the limitations of treating the respective materials; and because, inasmuch as the samples were representative of the districts from which they were obtained, this in-formation should be helpful in the future development of these districts. The present report is a compilation of results of brief preliminary tests on oxide ores only, which contained gold and silver and in some cases base metals. The methods of treatment used include gravity concentration, amalgamation, flotation, and cyanidation. For the most part, only standard laboratory procedures were employed. No attempts were made to develop new methods for the low-grade refractory ores in this group of samples if simple treatment was not successful, as the stage of development of the properties did not warrant extensive experimentation on the samples submitted.

Jan 1, 1951

By Sandra M. Stash

An integrated copper production complex includes mining, milling and smelting facilities which are usually at or near a common site, and sized to complement one another in capacity. There may also be an electrolytic retlnery serving the complex, but not always totally dedicated to its production. Mines and mills without co-owned smelters are not usually considered integrated. The first marketable product of an integrated complex is blister, or in some cases electrolytically refined copper. The nature of integrated operation brings together all of the environmental issues associated with copper production, but currently operating and newly planned facilities are required to anticipate these issues and meet stringent regulations. Older complexes, however, may have legacies of 50 or more years of operation unencumbered by current levels of environmental strictures: nevertheless, they must be remediated. Using examples from closure and remediation of the mining and mineral processing facilities in the Upper Clark Fork River Basin of Montana, the authors review some of the problems encountered since CERCLA's1 enactment in 1980, and the solutions to those problems, bearing in mind that not all of the problems and solutions were technical. Much has been written about the mines of Butte -the "Richest Hill on Earth" as it was known in its day and the mills, smelters and refineries they spawned. These facilities comprised an archetype of the integrated copper complex: from ore to metal in facilities serving and depending on one another. Many great stories of technological innovations and business triumphs have been told about Butte and Anaconda's mining history and the place The Anaconda Company occupies in that history. However, relatively little has been written about the final days: 25 years during which the once-great complex was closed, and the remnants of past glories were remediated after nearly a century of operation. This paper offers some insights from the real world affecting similar complexes still operating, and, hopefully, lessons for others just starting down the path to final closure.

Jan 1, 2003

By M. Sanchez

In the last decades, the Chilean copper mining and metallurgical industry have had to modify their technological processes to meet the environmental regulations implemented by the Chilean government, and also to support the pressure of the public opinion. Thus, air quality standards for sulfur dioxide and particulate matter (primary and secondary), plans for reducing emission of arsenic by the Chilean copper smelters, effluents discharge limits, among others regulations were applied by the environmental agency. Additionally, agreements on cleaner production were carried out by mining sector and government. Now, a draft law on mine closure, and another on environmental mining wastes (abandoned mines) are being discussed by the authorities and the mining sector. In the context, production and environmental impacts in different ways to produce copper in the Chilean mining industry are reviewed and regulatory tendencies as well as abatement technologies today used are exposed and discussed in this presentation. Pyro, hydro and electrometallurgical processes employed and their current effluent and contaminants are presented showing various alternatives of treatment in the copper industry. An update of regulations established in Chile vis a vis copper production, with an especial attention to mine closure are also presented.

Jan 1, 2007

By Moenster J. A., M. J. Sankovitch

Doe Run's Buick Smelter was converted from a primary lead smelter to a secondary lead smelter in 1991. The recycling facility was designed to produce 60,000 tons of refined lead per year from 110,000 tons of spent starting-lighting-ignition (SLI) batteries and 10,000 tons of lead contained in drosses and scrap. Since commissioning, Buick's refined lead output has steadily increased to exceed 120,000 tons for 1999. The production gains have been the result of continuous process improvements, empowerment of the workforee, and development of additional scrap lead streams. The production gains were accomplished while setting industry standards for employee safety, reducing plant environmental emissions and employee blood leads, achieving ISO 9002 certification, and expanding product lines to meet customer requirements. This paper highlights Buick's major accomplishments through the 1990's.

Jan 1, 2000

By E. P. Youngman

Great Britain has never had a basic raining law such as is in force in most foreign countries. This lack may be due to the fact that, with the exception of gold and silver, all metals or minerals belong to the owner of the surface land. Even with respect to the precious metals, gold and silver, which are not abundant in Great Britain, the right of the Crown, though still technically acknowledged, is not always insisted unon. All other metals and minerals are vested in the ground landlord, who may sell, lease, or other¬ wise convey them. The State has little to do with the mining industry except in. regulatory and judicial matters. The Government must settle controversies and provide for easements, rights of way for railroads, roads, and canals, or, in general, effect the same control that it exercises over other industries. As mining was carried on in very early times in England, of necessity a certain legal procedure came into existence, which in effect was little more than a private contract between the owner of the mineral (whether an individual or the State) and the miner. The nature of such contracts, of course, has changed radically with the changed relations between classes, as England lias developed from the feudal into the modern State. From the medley of ancient procedure and custom, a concession system of mining in^its simplest form lias evolved. Of the earlier conditions. Van Wagenen says

Oct 1, 1931

By M. Nambiar

Due to the remote locations of the mining projects and the demand for long transmission lines to provide electrical power, mining sites often operate with poor network power quality and low short circuit capacity. In order to cope up with this situation, more and more mining projects are considering the installation of appropriately designed Synchronous Condensers(SC) together with Power Factor Correction and Harmonic Filter System(PFC&HFS). The installation of these power quality equipments is viewed as a technological advancement in the mining application. An adequate level of short circuit power is essential and has to be ensured for the safe and reliable operation of especially large cycloconverter driven gearless mill drive systems used for grinding application. Increase in plant short circuit power is generally achieved by lowering the impedance of the supplying network. The SC also provides smooth voltage control during mill starting or major load trips, thereby regulating the plant voltage within the required limits. This paper will explore the impact, technical advantage and reasoning for the selection of the advanced hybrid technology mentioned above, in order to cope with the power system challenges for future mining projects. It also highlights the potential problems and how to address them carefully.

Feb 23, 2014

By F. G. Schwartz

The Bureau of Mines developed a rapid and precise method for predicting storage stability of motor gasolines. This method resulted from the investigation of many analytical techniques as well as a study of fuel composition and fuel component gum-forming mechanisms. The first section of this bulletin discusses the development of the prediction test through its several phases, including revision of the standard 110° F storage test; attempts to develop a modification of the ASTM D525 induction bomb test; and the ultimate abandonment of this procedure with the adoption of the 16-hour oven test that was both precise and rapid. The second section comprises a discussion of further studies of fuel com- position, including the reactivity of certain sulfur compounds and hydrocarbons to form gum. The compositions of various gums and inorganic deposits are reported in terms of elemental analysis and spectroscopic examinations. The reactions of tetraethyllead with selected hydrocarbons are also reported.

Jan 1, 1972

By R. J. Kolada

The ventilation systems of coal storage silos are normally capable of rapidly dispersing any accumulations of methane in the atmosphere above the coal pile surface. However, the results of an investigation which is presented in this report show that hazardous concentrations of methane can accumulate within the coal pile. Methane trapped within the coal pile is released into the atmosphere of the loading gallery when coal is discharged from a silo. If the methane released is of a flammable concentration it is necessary to ventilate the gallery to reduce the risk of an ignition. This report proposes a simple test, which, after further investigations may prove to be an effective method to calculate gallery ventilation requirements.

Jan 1, 1985

By J Rayo

Andean countries (Chile, Peru, Bolivia and Argentina) have 42 semi-autogenous mills (SAG) in operation and there are more than 30 projects in the pipeline that consider SAG mills. At the end of the next decade, the total amount of SAG mills in this area will likely be close to 100.There is a lot of reliable operational information collected by JRI Ingenieria Sociedad Anonima, the author’s engineering company, for more than 20 years and processed by statistical software, to be used as a reference for design basis of future projects or to improve operations by comparison. JRI Ingenieria Sociedad Anonima has reliable information related to the performance of more than 50 per cent of the Andean SAG plants.The paper presented considers a set of graphs that summarise the collected and verified SAG plants technical data. The figures will show key parameters as circuits and equipment data, energy consumption, technical availability, utilisation rates, throughput variability, pebble productions, steel consumption and others.The data is compared with typical design basis of several engineering companies and the main differences are analysed and/or commented on.CITATION:Rayo, J, 2014. Comparison of semi-autogenous mills operations in Andean countries, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 283–296 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By F. Dehghani, M. Kebe, H. Askari-Sabzkoohi, T. Ghosh

The depletion of bauxite reserves around the world has necessitated the search for viable alternative sources of aluminum. The major non-bauxite source of aluminum is alunite [KAl3 (SO4)2(OH)6]. Lixiviation is the common industrial process to recover aluminum from alunite. Due to the presence of quartz (40%) as the main gangue mineral, this process causes the formation of Sodium aluminosilicate and Potassium aluminosilicate complexes that leads to loss of alunite, and chemical reagents. Thus, pre-concentration of alunite is required to remove the gangue minerals. Because of the low degrees of freedom (DOF) of alunite, froth flotation, as a preconcentration method, is a viable alternative to increase selectivity in downstream processes. In this work, the possibility of Alunite preconcentration with micro flotation and mechanical flotation cells was studied. The influence of type and dosage of collector, pH, solid percent, particles sizes were considered on the flotation. Flotation tests were designed based on Taguchi method, followed by performing based on surface charge differential between alunite and quartz on direct and revers flotation. In the reverse flotation, Ca+ 2 and Ba+ 2 were used to activate the quartz surface. Under optimum conditions of reverse flotation, alunite grade and recovery were 40% and 62.1% respectively. In the direct flotation, the surface of alunite was activated by F- . The grade and recovery were 50 and 89%, respectively.

Mar 2, 2022

By P. C. McWilliams

The Bureau of Mines investigated ground support problems in four major block-cave mines to assess the current "state-of-the-art" and to delineate areas for future research. The most significant problem is the inability of present support systems to hold moving ground. Further, as mining progresses to greater depth, this problem becomes more serious. Providing adequate temporary support capable of withstanding primary and secondary blasting is the next most significant problem. A detailed analysis of the effect of mining methods on support problems is also recommended for future research.

Jan 1, 1975