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By Khamis Y. Haramy

This Bureau of Mines paper describes the use of the borehole shear tester (BST) In mines. Assembly and procedure sections explain how the equipment is assembled and used properly. Schematics of the BST, limitations, test hole specifications, data recording and calculations are all explained briefly, and an example of the data collecting and calculations is given to assist understanding.

Jan 1, 1981

The Rate Variable Batch Test (RVBT) - A Research Method of Characterising Ore Floatability

Sep 13, 2010

THE Broken Hill mining field, approximately 31 miles in length, is at present being exploited by seven companies, viz. : North Broken Hill Limited, Junction North Broken Hill No Liability, Broken Hill Proprietary Block 14 Company, Broken Hill ProprietaryCompany Limited, Sulphide Corporation Limited, Broken Hill South Limited, and Zinc Corporation Limited.The variation in size and shape of the ore-bodies in the mines of these companies, together with the many alterations in pitch and dip, necessitates differences in methods of mining, each company working out its problem in its own particular way.In the matter of chute construction for the handling of the ore broken in the stopes, each mine belonging to the above companies has adopted a style particularly its own, though it may be said that one or two of the types approximate very closely to each other, slight minor differences only being noticed in the design. It is the purpose of this paper to give a brief description of the principal types of chutes now in use in th,e various mines on the field, and in doing so they may roughly be classified into three groups, viz:1. Bulk Chutes, 2. Circular Chutes, 3. Square-set Chutes.The Bulk type of chute is used in the North and British mines of the North Broken Hill Limited, the Central and Junction mines of the Sulphide Corporation, the South Blocks mine of the Zinc Corporation, and the Block 14 mine.The Circular type of chute is used by the Broken Hill South mine and the South Blocks mine.The Square-set chute is used in the Proprietary mine, the Junction North mine, and occasionally in other mines where the square set method of mining is a necessity, and more particularly as mullock passes.

Jan 1, 1925

By Joseph C. Gillen

This paper discusses the design, construction, and performance of the support of excavation system used at The Atlantic Building jobsite. The support of excavation system had to be adaptable to the different conditions surrounding the site. These conditions included support of four historic building façades, including the nine-story Atlantic Building, as well as support of three historic row-houses along two walls. Directly adjacent to the site is the historic Ford?s Theatre and townhouse. Across a 15? alley is the American Immigration Lawyers Association (AILA) Building, and across a 30? alley is the Federal Election Commission Building and another ongoing excavation. Of historical note, these two alleys were the escape route for John Wilkes Booth following his assassination of President Lincoln. With the excavation being 53? to 58? deep, the system included driven and drilled soldier piles, drilled bracket piles, and two modified tangent walls. The bracing included tiebacks, corner braces, wales, cross lot struts, and a specially designed support system for the nine-story façade. The footprint of the excavation included 12 corners and all alleys and streets were to remain open during construction. The performance requirements for system movement at Ford?s Theatre and AILA Building were ½ inches in the horizontal direction. The modified tangent walls were used in these areas to provide stiffness. The soil conditions at the site were fill material on top of a shallow, sandy, silty, gravel layer on top of a deep layer of soft organic silt and clay. Below the silt and clay layer was fine sandy material at the subgrade.

Jan 1, 2006

By Joel Darmstadter

The position of the coal industry in America’s fuel and power picture remains one of prime importance. Measured in Btu terms, the industry is the country’s leading energy producer and an important exporter. Foreign coal sales yield annual proceeds of about $4 billion. Coal’s one-fifth share of the nation’s energy consumption is nearly as high as that of natural gas. Coal is the electric utility sector’s principal fuel supplier. It accounts for about55% of the electricity generated at power stations.

Jan 1, 1999

By F. W. Wood

The use of consumable.-electrode arc melting as a production technology is growing. One advantageous feature of this process is that it avoids ingot contamination by soluble crucible materials by employing a chilled metal crucible. Because the thermal balance under these conditions is rather delicate and does not necessarily provide a favorable environment for solidification, catastrophic imbalances can occur. The effectiveness and mechanistic roles of various factors are mostly unknown, and more intelligent insight regarding the distribution of temperature and heat is needed. Experience has provided several pertinent observations, some of which are quite superficial. The most meaningful data have resulted from studies of molten pool shapes and sizes and from measurements of heat flow through crucible walls. Overall experience, intuitively interpreted and supplemented, is sufficient nevertheless as a basis for a boundary-value treatment of the problem. A mathematical analysis based on a separation of variables, using conventional differential equation methods, provides a useful solution. For a cylindrical ingot, the temperature varies as a Bessel function of an argument proportional to the radius and as an exponential function of longitudinal position. Trial calculations using the problem solution seem to verify the general correctness of the result as compared with experience. The role and nature of solution parameters are also clarified, though not entirely resolved. It is revealed that the barrier to heat flow at the ingot-crucible surface has a prominent influence. Utility of the model embodied in the problem solution is readily demonstrated by considering a variety of contemporary questions about arc melting, and it is hoped that utility can be enhanced by improvement of the model.

Jan 1, 1968

By Lucas Lopes da Costa

In this work, a natural foam extracted from the Amazon buriti palm tree is investigated as possible substitute for synthetic foams. The basic physical and mechanical properties of this biofoam were evaluated. Its sponge-like structure was characterized by the amount of pores and morphological aspects. It was found that the buriti biofoam displays a very low density of the order of 0.1 g/cm3 with a relatively good compressive strength. This would be suitable for several engineering applications and as a new material with the potential for replacing currently applied synthetic polymeric foams.

Jan 1, 2010

By William R. Yernberg

The “China & East Asia Mineral and Energy Re-sources Symposium — CEAR 2000” was held Jan. 23-26, 2000 in Denver, CO. Conference sponsors included Resources and Technology Symposia of Colorado and the Asian Journal of Mining. The meeting was attended by representatives from China, Japan, Mongolia, Korea, eastern Russia (Siberia) and the United States. The US attendees consisted of interested parties from mining and energy companies, financial institutions, consultants and government agencies. In his opening statements, L. Maness, Jr., president of Resources and Technology Symposia of Colorado, said that the “goal of the conference was to make jobs and friendships and to introduce people to each other.” The conference provided an opportunity for Western mining interests, including mining companies and investors, to meet with government agencies from both sides of the Pacific.

Jan 1, 2000

By R. G. Votteler, A. C. Brent

"The business performance of mining corporations in South Africa is adversely affected by the constantly increasing electricity costs. The most commonly used power sources are the national utility supplier via a grid connection, and on-site diesel generators. Previous research has identified the renewable sources of solar photovoltaic (PV), onshore wind, and geothermal energy in hybrid versions with current sources as possible opportunities to counteract rising electricity costs. To provide a clear understanding of the new, developing market of renewable energy sources, this research is divided into two papers. This first paper investigates the internal business structure of mining corporations in order to evaluate electricity generating sources. The multi-criteria decision analysis (MCDA) method is selected as the most suitable approach for this. The paper identifies the criteria used by mining corporations to evaluate possible electricity generation sources for self-generation by means of the corporations’ own investment. Four mining corporations with several mining locations were interviewed. The interviews revealed both new and identical evaluation criteria when the findings were compared to earlier MCDA adaptations analysed in the literature review. The second paper (Part 2) combines current knowledge about the external macroeconomic environment with the findings about the internal environment described here. MCDA is adapted in Part 2 and implemented to analyse and compare current to hybrid renewable sources from the perspective of mines. IntroductionMining corporations in South Africa are currently adversely affected by increasing electricity prices. Electricity is supplied mainly by Eskom1 and, especially in remote locations, by on-site diesel generators (Boyse et al., 2014). Electricity price increases, emanating from diesel price hikes and Eskom, have escalated the total operational expenditure on electricity by the largest mining corporations from 8% to 20% of total operating costs in the past seven years (EIUG, 2015). The reliability of electricity supplied by Eskom has decreased drastically (Govender, 2008), and the prices will increase annually by at least 13% until 2018 (Numbi et al., 2014; Eskom, 2015b). In addition, the South African government plans to introduce a carbon tax on greenhouse gas emissions (Alton et al., 2014)."

Jan 1, 2017

By U. Paschedag, H. Bussmann

"Bucyrus manufactures the most comprehensive product portfolio of mining equipment worldwide. Its mission is to have a positive, lasting effect on our world. Bucyrus makes sustainable development a fundamental way of doing business through economic, environmental and social initiatives that support, educate and benefit our employees, customers, shareholders and other stakeholders. Our participation in GRI (Global Reporting Initiative), a network-based organization that has pioneered the most popular sustainability reporting framework will be discussed as well as examples will be given on each major field of engagement. Two examples from surface machinery are most fuel efficient haul trucks as well as the Highwall mining system which allows access to coal reserves which are lost not making use of this kind of system. Two examples from underground machinery are Bucyrus’ automated plow systems for the mining of medium and thin coal seams with minimum rock and Bucyrus’ intelligent CST drive system for high-powered armored face conveyors (AFCs) for efficient use of energy."

Jan 1, 2011

By J. W. Merkley, K. B. Hustwick

"The authors describe the use of a computer system for the control oj warehouse inventory at Cominco's Canadian operations. The challenge presented by the company's diverse products and various locations necessitated a practical approach to operational and manpower requirements. The utilization of modern forecasting techniques, manual intervention and exception reporting provides system flexibility. The system also provides both operational and management control to set required service goals at the lowest inventory levels for inventory management.IntroductionCominco Ltd. is a Canadian company, with international operations, the principal business of which is zinc, lead and chemical fertilizer s. Its involvement is fully integrated and range s from mineral exploration through mining, smelting, refining and by-product production to international marketing. It also embraces related services, including trade, wharfarge and power. With head office in Vancouver, it is involved, directly or through subsidiary or associated companies, in Canada and in the United States, Greenland, Europe, Australia, India and Japan.Cominco has over 12,000 employees and 26,000 shareholders, with 91% of all shares held in Canada.Cominco's Inventory Control System is one of the most extensively used computer systems employed by the company. Also, inventory control is regarded as one of the most economically successful computer applications to be undertaken by the Data Processing Services (D.P.S) Group that was responsible for the development of the Inventory Control System.The main use of automatic inventory control has been at operating plants in Western Canada and the Northwest Territories, which are separated by large distances. Each location has equipment-intensive mining and processing operations and it is essential to maintain control of parts and supplies inventories. Some of these locations are remote from urban and industrial centres and it is important to avoid the adverse effects of high personnel costs and re-training due to turnover."

Jan 1, 1982

By Charles Taschereau

The statements made in this presentation contain certain forward-looking statements concerning potential developments affecting the business, prospects, financial condition and other aspects of Canada Lithium Corp. The actual results of the specific items described in this presentation, and the company?s operations generally, may differ materially from what is projected in such forward-looking statements. Although such statements are based upon the best judgments of Canada Lithium Corp. management as of the date of this presentation, significant deviations in magnitude, timing and other factors may result from business risks and uncertainties including, without limitation, the Company?s dependence on third parties, general market and economic conditions, technical factors, the availability of outside capital, receipt of revenues and other factors, many of which are beyond the control of the Company. Canada Lithium Corp. disclaims any obligation to update information contained in any forward-looking statement. Toronto Stock Exchange: CLQToronto CLQOTCQX: CLQMFOTCQX: CLQMF

May 1, 2011

By Felipe Calizaya

This study describes the principles involved in the design of a booster fan installation, the basic requirements, and the provisions needed to guarantee a safe operation of the unit. It also describes how a booster fan should be selected and what measures should be taken so that events such as uncontrolled recirculation of air in a mine can be avoided. A computer program called MFSELECT is presented to assist the ventilation engineer in the design process a For a given mine ventilation network, the program determines the duties of fans and regulators that will fulfill the airflow requirements of a mine and minimize the total power consumption. The application of the program is illustrated by the detailed solution of a sample problem. A Case Study based on the Jim Walter Resources' No. 7 Mine is utilized to describe the basic requirements for the design and operation of booster fans, and illustrate their potential benefits in mine ventilation. Finally, the study discusses a process control system designed to evaluate the safety conditions in the mine and report on the status of both surface fans and underground booster fans.

Jan 1, 1990

By R. Matusewicz

The key drivers for the copper smelting industry are a complex mix of economic and "human" factors which combine to drive technology in new directions and can provide a strong indication of future industry trends. Recent examples have been the drive to achieve increased scale of production and resultant cost efficiencies by using a single furnace high intensity smelting vessel, and the broad acceptance of Top Submerged Lancing (TSL) technology for this duty. The development and adoption of continuous converting processes to counter the increased pressures faced by the Peirce Smith converting process is another example of the need for innovation. This paper discusses the merits of the continuous converting process, describes how the Ausmelt TSL batch converting process has been adapted to the new Ausmelt Continuous Copper Converting (C3) process in response to these industry trends and examines the Ausmelt continuous converting flowsheet options available to the end user.

Jan 1, 2007

By H Zhang, A Lawrence

To accommodate the fast growing need for services in Singapore’s Marina Bay downtown area, Marina South, the construction of a common services tunnel (CST) was required. The CST includes various services such as telecom cables, power lines and water pipes. A deep excavation and temporary earth retaining system (TERS) was required to facilitate the construction of the tunnels. Marina Bay is reclaimed land over thick soft marine clay which is likely to be still consolidating. The deep soft marine clay poses a big challenge for deep excavations in downtown areas where highways and sensitive structures are close by. This paper presents a case study of part of the CST Phase 1B and 2 at Marina South, in particular a 26 m deep excavation supported by a 46 m diameter temporary caisson. The construction started in late 2006 and the basic structure was completed in early 2011. The caisson was formed by 1.0 m thick overlapping diaphragm wall panels with a capping beam and three ring beams at different depths. Two-dimensional finite element analyses were conducted to predict the ground settlement, lateral displacement, bending moment and hoop stresses in the diaphragm wall and ring beams during different excavation stages. A comprehensive instrumentation and monitoring scheme was established to verify the design predictions, control excavation safety and trigger the contingency plan to protect public safety. The impact of construction activity, unbalanced temporary stockpiles and adjacent deep excavation for a mole removal will be discussed.CITATION:Zhang, H and Lawrence, A, 2014. A case history of a deep excavation in a big circular shaft in Singapore marine clay, in Proceedings 15th Australasian Tunnelling Conference 2014, pp 581–588 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By W. L. Cooley

A significantly different method of evaluating mine ground system safety is investigated. The method measures touch and step potentials around ground beds and grounded equipment resulting from a series of extremely small simulated faults. The values are then scaled for a full-scale fault. The method should be particularly useful for large ground beds and under conditions where the ground bed cannot be isolated from the rest of the ground system in order to make traditional ground bed resistance measurements. Instrumentation for making the alternative measurements is evaluated under rigorous field conditions. A step-by-step procedure is proposed for evaluating a surface mine ground system. This procedure was subject to several field tests at eastern metal/non-metal mines. The final evaluation procedure is written as a stand-alone document for use by MSHA inspectors and mine operating personnel, and is included as an appendix to the report. The authors conclude that the procedure is effective in evaluating ground system safety and recommend that it be further evaluated in the field.

Jan 1, 1985

By S. C. Richardson

The electrowinning (EW) circuit involves using DC current in the electro-deposition of metal ions dissolved in an electrolyte solution. This paper reviews a method to generate an electrical model of an EW circuit and the resulting DC current flow and voltage distribution within the circuit. Topics include: calculations of electrolyte conductivity and the equivalent electrical resistance of the electrolyte within the electrolyte pipelines connected to the EW circuit; the breakdown and classification of the EW cell voltage into thermodynamic and ohmic potentials; methods to calculate current flow and voltage distribution throughout the EW circuit; and the development of an interactive visual computer model to simulate an actual EW circuit. Stray current can pose an electrical shock hazard to employees in electrolytic tankhouses. Increased awareness and understanding of the voltage distribution and potential stray current in an EW circuit can help mitigate the risk of tankhouse workers becoming exposed to electrical shock hazards. INTRODUCTION Copper electrowinning tankhouses include rectifiers that deliver large amount of DC current to a series of electrolytic cells consisting of electrolyte solution and electrode pairs. The design also includes metallic conductors in the circuit which include the rectifier’s positive and negative busbar, inter-cell busbar, and the anode and cathode frames. The electrolyte acts as an electrical conductor that transfers current via ions between the anodic and cathodic electrodes within the cell. Electrolyte, as a conductor, is also capable of conducting DC current outside the main EW circuit through the connected electrolyte feed and return pipe systems. DC current that follows a path other than the intended path through the series of electrolytic cells is referred to as “stray current”. Developing an electrical model enhances understanding of voltage distribution and current flow in an EW circuit. This paper discusses the derivation of the various representative components of the model as well as the output from the model. An interactive visual computer simulation incorporates the model output in order to aid in the understanding of voltage distribution and current flow throughout the EW circuit.

Jan 1, 2019

Surface subsidence that results from longwall mining can be large magnitude and can affect significant areas. Conventional methods for subsidence monitoring include leveling, global positioning system (GPS), and photogrammetric surveys. Remote sensing techniques, including aerial LiDAR, terrestrial laser scanning, and satellite-based differential interferometric synthetic aperture radar (DInSAR), are also used to measure deformation associated with subsidence. DInSAR data are different than data from conventional subsidence surveys. Images capture data over large areas (hundreds of kilometers), and each pixel (data point) in an image quantifies the average displacement over an area of square meters. DInSAR data can have fairly high time resolution; imaging periods typically range from weeks to months.

Jan 7, 2020

By George McIvor, Bill Thompson, Don Whitmore, Brad Rhude

"In 1972 Manitoba Hydro decided to develop the hydro electric potential of the Nelson River. This program included the construction of the Jenpeg Generating Station at the point where the channel of the Nelson River discharged into Cross Lake. The Jenpeg station serves two primary functions: 1) Provides a control structure for the regulation of Lake Winnipeg.2) Acts as a 126,000 kilowatt hydraulic generating station."

Jan 1, 1992

Spectrum Resources commenced operations as a public listed mining company in August, 1983, with a variety of precious metal projects in New Zealand. At that time the outlook for most mineral commodities, with the notable exception of precious metals, was decidedly gloomy. Metal prices were depressed and demand forecasts were universally gloomy. Against this background the company reviewed the non-traditional metals sector to try and identify a 'new' metal with an above average demand growth and market value. Lithium, a commodity with exciting new applications in storage batteries and alloys, met both criteria. Annual world consumption of lithium is around 7000 tonnes; current prices are around $NZ40/lb for lithium metal and demand growth is projected at five to seven per cent per annum. Geothermal fluids at Wairakei and elsewhere contain anomalous amounts of lithium and in May, 1984, the Chemistry Division of DSIR was commissioned to carry out a literature survey on the possible recovery of lithium and other minerals from geothermal waters. The survey results were encouraging and the company subsequently negotiated exclusive access rights, for research purposes, to geothermal discharge fluids from the Wairakei and Kawerau geothermal fluids. Most of the subsequent investigations reported here were carried out by Chemistry Division, DSIR, under contract to the company with some assistance from the Industrial Processing Division, DSIR.

Jan 1, 1986