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By J. J. Cai

The status of fossil fuel and secondary resource in metallurgy industry in China were reviewed, and conversion efficiency of fossil fuel, utilization technologies of secondary energy were studied. Fossil fuel, accounting for over 90% of energy structure in metallurgy industry, took in the highest flight in China, and a great deal of which was converted to secondary energy through the equipment of blast furnace and coke oven. These secondary energy which were mostly made of blast furnace gas(BFG), coke oven gas(COG) and Lindz Donawitz gas(LDG) occupied about 30% of total secondary energy. The way enhancing fossil fuel conversion efficiency, secondary resource recovery and the secondary energy such as BFG, COG, LDG utilization promoted to save fossil fuel was discussed in this paper. And efficient use of lower caloric value fuel was studied, such as preheating combustion air and fuel, generating electricity power etc. and regeneration purposes of high-caloric fuel was also researched, for producing hydrogen, methanol or direct reduction iron etc. The using model of secondary energy at iron and steel works was presented as fuel and chemical materials. The results suggest that utilization of these energy efficiently and reasonably could help to energy saving and environment protecting.

Jan 1, 2014

By Raymond P. Miller

This two volume report addresses slope stability of surface mine spoils within the Interior Coal Province. Sixteen (16) mines were visited, pertinent data and samples collected, and reported spoil instabilities back-analyzed. Laboratory test results are compared to back-analyzed material properties. Available methods of slope stability analysis are reviewed and evaluated with respect to application to mine spoil stability evaluation and prediction. Correlation and tentative relationships among spoil material properties, highwall conditions, mining equipment and procedures and empirical observations are presented. Slope stability sensitivity plots illustrate the relative significance of various input parameters on stability. Slope stability input parameters are correlated with site and mining conditions to identify the primary factors controlling spoil stability. Investigative methods, spoil stability enhancement techniques, spoil stability prediction procedures and future study areas are discussed. Appendices include a glossary of terms, annotated bibliography, details of mine visits, and detailed laboratory test procedures and results.

Jan 1, 1979

By E. A. van Wyk, M. R. de Villiers

"Mining companies strive to increase and maintain production, while simultaneously remaining competitive in the global economy. Furthermore, they must ensure workers’ safety and maintain good safety records. The use of virtual reality (VR) facilitates the development of tools and systems for various purposes that can improve knowledge and understanding of the work environment. VR is a rapidly growing technology that uses the ever-increasing power of computing to simulate real-world and imaginary environments and situations with a high degree of realism and interaction. The availability of 3D modelling tools and simulation programming engines that work effectively with a mid-range desktop PC and standard 3D graphics card, make VR technology viable and attractive for mainstream training applications. The design, development, and implementation of interactive VR training systems is proposed as an innovative approach to augment safety training. However, in order to assess the impact of such VR training systems it is of particular importance to determine the effectiveness of the design of such systems. This article proposes an evaluation framework for this vital purpose. This framework comprises criteria to assess VR training systems, specifically relating to usability, instructional design, VR systems design, and mining industry context-specific aspects. Although the framework was developed as an evaluation tool to assess effectiveness of the design of such systems, it can equally well be used as a set of design principles to inform the design of VR training systems for mining. IntroductionMining in South Africa has been the main driving force behind the history and development of Africa’s richest and most advanced economy (Coka, 2012). The South African mining industry is frequently criticised for its poor safety record and high fatality rate (Stoddard and Skweyiya, 2016). Inadequate or insufficient training is often cited as a root cause of accidents (Van Wyk and De Villiers, 2009; Tichon and Burgess-Limerick, 2011). Virtual reality (VR) is a rapidly growing technology that utilizes the ever-increasing power of computing to simulate real-world and imaginary environments and situations with a high degree of realism and interaction (Webber-Youngman and Van Wyk, 2013). VR is currently being used or investigated as a training solution in a variety of industries. VR technology has developed rapidly and costs have fallen to levels where it can now be considered for mainstream training applications. The availability of 3D modelling tools and simulation programming engines that work effectively with a mid-range desktop PC and a standard 3D graphics card, make VR even more attractive to mine training centres (Van Wyk and De Villiers, 2009)."

May 1, 2019

By John F. Papp

International and U.S. chromium material flow, losses, and environmental releases and transfers from mining through industrial processing, end use, and recycling are identified and quantified. Average (1983-92) U.S. consumption has been: metallurgical industry, 87 pct; chemical industry, 10 pet; and refractory industry, 3 pct. Average chromium content of aluminum, cobalt, copper, nickel, and titanium alloys and alloy, carbon, and stainless steel alloys was estimated. Anthropogenic chromium consumption was estimated for the cement and copper industries. N on-commodity cycle anthropogenic chromium mobilization resulting from U.S. fuel and fertilizer use was estimated. Commodity cycle anthropogenic world chromium loss from mining and primary consumer industry was estimated to be equivalent to about 56 pct of chromium contained in chromite ore production and represented a loss rate of 181 kt-Cr/Mt-CrOre. Chromium released to the atmosphere from natural and from anthropogenic sources were comparable in magnitude. Chromium released to soil was mostly from anthropogenic sources, and aquatic releases were all anthropogenic. Domestic product chromium losses exceed process losses by more than a factor of 10 showing the importance and potential environmental impact of post-consumer recycling. The location of historical and current domestic chromium industry processing sites in 23 States were reported. Chromium releases and transfers to the environment were estimated from 1973 through 2002 by primary consumer industry. A decrease in chromium releases and transfers to the environment was anticipated.

Jan 1, 1995

A Good Product Range - So What! While in terms of water, waste management and environment protectrion, the Gippsland Basin may appear to have a good product range, what does this really mean? What it means is that, like any product range, the virtues of the product range must be sold and accepted by a majority of the public. The social, economic and environmental benefits of any enterprise using these products must be sold and accepted by the regional population. Many a budding entrepreneur has failed because he assumed that the public would accept his product, so good did it appear to be! However, we know that such an assumption must be avoided and that a great deal of time and effort needs to be invested in promoting and gaining acceptance of a product to ensure a long term and viable market.

Jan 1, 1992

By B Dodd

This paper details how the Australian Securities and Investments Commission (ASIC), as a disclosure and conduct regulator, approaches regulation of continuous disclosure, capital raising and control transactions in the mining and resources sector, and the reasons for the approach. In examining this topic the paper considers the Joint Ore Reserves Committee (JORC) Code (JORC, 2004), the VALMIN Code (VALMIN Committee, 2005), the relevant ASX Listing Rules and the relevant provisions of the Corporations Act 2001 (Corporations Act). This paper discusses ASICÆs approach to expert reports and disclosure with reference to Regulatory Guides 111 Content of expert reports and 170 Prospective financial information.CITATION:Dodd, B, 2012. Issues in capital raisings and disclosure, in Proceedings International Mine Management 2012, pp 3-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By A F. von Wielligh, M Scott, L Keeney

Operational Grade Engineering (GE) is the early (pre-processing) discard of low-grade mineralised and/or barren rock to improve the ore grade and/or reduce deleterious elements within the run of mine ore to be processed. GE activities generally have an impact on primary and ancillary mining activities, equipment utilization and overall equipment productivity. By discarding material which would have reported as ore (in a non-GE mine plan) means that GE must increases the total ore and total rock mining rate requirements to sustain mill feed targets. One challenge of GE and the planning of GE activities is that there are several indirect parameters which impact operational productivity. Modelling these potential impacts and determining if they can be overcome with alternate mine sequences, equipment application or possibly a different equipment fleet altogether is a key question requiring investigation. Overcoming these potential productivity obstacles associated with a more complex operation by introducing new operational parameters and destinations for ore and possibly sub-grade blocks, requires a GE mine plan that is coupled with detailed equipment productivity metrics and a sound operational plan incorporating all GE infrastructure requirements. Several GE mine plans and equipment productivity models indicate that mining rates generally need to increase by approximately 5% to 15% to sustain mill targets and often negatively impact equipment unit productivity metrices through increased cycle times, additional queuing and destination changes. These changes to productivity metrics are however offset by step change increases in asset value. This paper details a methodology to develop GE mine plans that incorporate equipment modelling, flexible mine sequencing and equipment-based production scheduling. In addition, the paper will outline impacts of GE planning on equipment unit productivities through worked examples and models.

Nov 10, 2020

By A L. Zawadski, B G. Putland

"This paper discusses a method to build a calibrated comminution circuit model, using historic operating data and blend information that is useful for forecasting and optimising plant performance, as well as evaluating expansion opportunities. A preferred method for building a calibrated power-based comminution model is discussed and justified based on two case studies, offering low-cost and effective strategies to utilise existing information for the maximum possible benefit.The first example is the Lefa Gold Mine located in Guinea, West Africa operating a semi-autogenous grinding (SAG) and ball milling circuit with recycle crushing (SABC). Daily blend information and operating data was utilised to build and calibrate a power-based model of the comminution circuit. The least squares regression method was used to solve the SAG mill specific energy requirement and the operating work index (Wio) for each individual ore type. The calibrated model was used to evaluate expansion strategies to sustain throughput at higher proportions of fresh ore based on the proposed life-of-mine schedule.The second example is the Ok Tedi Copper-Gold Mine in Papua New Guinea operating a SAG and ball milling circuit (SAB). The circuit limitation would often shift between the SAG mill and the ball mill due to variable ore characteristics and feed blend. Typical SAG mill relief strategies, such as recycle crushing or secondary crushing, required significant capital expenditure and the potential throughput benefit would vary depending on ore type, making economic justification difficult. Daily blend information and operating data was used to build and calibrate a power-based model of the comminution circuit to identify ore types that might benefit from higher blast intensities to increase fines content, thus relieving the SAG mill limitation and increasing overall throughput without a major capital investment.Citation:Zawadski, A L and Putland, B G, 2016. Calibrating Comminution Models Using Operating Data to Forecast and Optimise Plant Performance, in Proceedings 13th AusIMM Mill Operators’ Conference 2016, pp 17–26 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Oct 10, 2016

By David Hopkins, Steve Klein, Bradford Townsend, Ed Sum, Derek Penrice

INTRODUCTION The Transbay-Caltrain Downtown Extension (DTX) Project involves the construction of an approximately 1.5-mile rail line that will extend Caltrain commuter service and the future California High Speed Rail system into downtown San Francisco. The underground rail extension will be constructed by mined tunnel and cut-and-cover methods. Tunneling challenges include difficult ground conditions, low rock cover, the presence of historic buildings along the alignment, and the large tunnel span, ranging from approximately 50 to 65 feet. Three mined tunnel construction methods were evaluated: the Stacked Drift Method, the New Austrian Tunneling Method/Sequential Excavation Method (NATM/SEM), and Tunnel Boring Machines (TBM). This paper describes the challenges presented within the mined tunnel section, and summarizes the evaluation of tunneling methods that led to the selection of NATM/SEM. PROJECT OVERVIEW The existing Transbay Terminal opened in downtown San Francisco in 1939. This facility is antiquated, and does not meet current building seismic safety standards or the transportation needs of the Bay Area. For these reasons, San Francisco voters approved Proposition H in 1999, which proposed to construct a new or rebuilt regional transit center at the site of the existing terminal and extend Caltrain commuter rail ser-vice to the new transit center. The new transit center is the hub of the Transbay Transit Center (TTC) Program, which will greatly enhance regional transit service by providing connectivity for six Bay Area transit providers at one facility. The program will be the largest inter-modal centerwest of New York City. The TTC Program is comprised of two major projects, the Transit

Jan 1, 2007

By R. C. Rowe

DR. W. F. GRAY (Contributed discussion, presented at meeting by Mr. S. C. Mifilen): Mr. Rowe's suggestion that the Institute should organize itself to interpret the needs of the mining industry to federal and provincial mines departments should commend itself to our membership as sensible and practical, and as one which these public administrative bodies may welcome. One has to start with the premise that those who head the departments of mines in question have the welfare of the industry at heart. Also, it must be postulated that the technical viewpoint of our membership is necessarily free of political considerations. With these reservations, one ventures to state that both Mr. Rowe in his communication to the present session of the Institute, and Professor M. Y. Williams in his earlier communication to the Western Meeting, on The Geological Survey and Mining Development (1), voice the regret general among our membership at the abandonment of the honoured name, and to some extent of the status, of the Geological Survey of Canada. The writer, in 1932, devoted his Presidential Address to the Institute to an appreciation of the value to Canadian mining of the Geological Survey of Canada (2), affirming the desire of the Institute "that the work of the Survey shall be maintained at the highest pitch of efficiency the resources of our country will permit, because, to scrimp expenses on the Survey, is 'to save at the spigot and lose at the bunghole'." He believes that is still the opinion of the Institute, and, if contraction of the usefulness of the Survey is feared by our members at this time, it is incumbent upon the Institute, in fairness to those who direct our government, to say so in precise and explicit terms. Mr. Rowe puts the situation pithily when he writes: "We have reached a stage in our development where a stock-taking and co-ordination of existing knowledge and data is essential. This is a part of that basic function of Dominion mineral technical services which is national and not provincial in its scope".

Jan 1, 1939

By Steven R. Pittman, Colin McCullough, Peter Galuska

"Traditionally Continuous Fiber Aluminum Matrix Composites have been fabricated using high strength fibers and high strength matrices, often commercial alloys, with the goal of producing high strength composites. However the specific role of the choice of matrix alloy on composite properties has not been well established. One way to control composite tensile strength is to use coatings to introduce a low strength interface between fiber and matrix which tends to reduce the importance of the matrix selection, but unfortunately renders the transverse strength unacceptably low. Thus using a system with strong bonding between fiber and matrix is desirable, such as an alumina fiber / aluminum alloy matrix system. In this case the transverse strength is a strong function of the matrix strength. However the longitudinal strength then depends largely on the characteristics of the matrix. The important role of the matrix is discussed using examples of alumina fibers in various aluminum alloy matrices. The key attributes are matrix constituent phases, alloy chemistry, alloy reactivity with the fiber, and matrix strength. From the understanding developed in these systems a set of design rules may be established for selecting an optimum matrix. IntroductionAluminum matrix composites (AMC's) reinforced with continuous fibers offer very attractive property gains over AI alloys, such as strength, stiffness, and fatigue resistance. These gains are magnified when specific mechanical properties are compared which make them attractive candidates for replacing steel, nickel, titanium and aluminum alloy parts in weight critical applications (1). Many systems have been tried in the past; B/AI, C/AI, SiC/AI, Si-Ti-C-O/AI and AI203/AI. Technically B/AI was a very good system but was expensive in regard to both fiber cost and fabrication and SiC/AI and C/AI systems are still plagued with reactivity problems. The Si-Ti-C-O/AI appears to be a good strength system but with lower stiffness. Until recently, the AI203/AI was a low strength system, in part due to a lack of a high strength fiber. Recently 3M introduced a high strength AI203 fiber - Nextel™ 610, which leads to high strength composites (1,2) and may also be both low cost and also compatible with less expensive casting approaches for fabrication."

Jan 1, 1996

By Wm. Mark Hart

High horizontal stresses and shear failure have been considered the major reasons that cause entry roof failure and falls for underground mining. Therefore, reorientation of the current mining systems or layouts or using angular crosscuts in mains or gate entries becomes more popular if a greater than normal horizontal stress is measured. However, reorientation of the current mining systems or layouts is always expensive and use of the angular crosscuts may weaken the pillar structure at corners. Therefore, cautions must be taken before any decision related to reorientation of the current mining systems or layouts or use of angular crosscuts is going to be made. In order to prevent entry roof failure and falls, the following two issues must be carefully examined and fully understood: 1. Which one, shear stress or tensile stress, is going to be blamed for entry roof failure? 2. Which one, horizontal stress, vertical stress, or local geological weakness plays a major role in entry roof failure and falls? This paper analyzes the mechanisms of entry roof failure and falls for underground mining in general examines the roof fall history at Springvale Colliery, and proposes the means of preventing roof failure and controlling roof falls for Spingvale Colliery in particular.

Jan 1, 1996

By W. K. Cunningham, Edwin A. Gee

"INTRODUCTION This paper is one of many reporting on various aspects of the Bureau of Mines program during World War II directed toward alleviation of shortages in certain critical minerals some of these papers are published as technical papers information circulars, and reports of investigations, of the Bureau of Mines or in technical journals.The investigation described in this report was begun as part of the Bureau, of Mines program to develop acid processes for the extraction of alumina from low-grade bauxites and clays. A domestic shortage of high-grade bauxite suitable for treatment by the Bayer process became acute as a result of World War II; and intensive search for a practical acid process using lower-grade alumina-bearing raw materials was therefore warranted.A survey of the various methods for extraction of alumina from clay has been presented in an early Bureau of Mines publication. 4/ The principal barrier to the successful operation of an acid process has been the difficulty experienced in developing a suitable commercial method for purifying the crude aluminum salts after the clay extraction is complete. Iron salts are the foremost contamination influence. A review of the more prominent procedures that have been proposed for separating iron and aluminum salts can be found in the well-known text on aluminum by Edwards, Frary, and Jeffries. 5/The majority of acid processes to extract alumina from clay employ sulfuric acid as the leaching agent, and the purification is thus reduced to the separation of iron and aluminum, sulfates."

Feb 1, 1948

By D. M. Baird

ABSTRACT A revised stratigraphic section of Carboniferous rocks which occupy about 700 square miles in southwestern Newfoundland is presented. Gypsum, which outcrops at thirty-five different localities, is found to belong to four principal zones in the section. The newly mapped structure of the region makes the otherwise random occurrences of gypsum appear as systematic outcroppings of the four zones which follow the regional structure. Details of several occurrences are given and those most advantageous for exploitation are pointed out. INTRODUCTION ROCKS of Carboniferous age occupy an area of about 700 square miles in southwestern Newfoundland. They occur in a belt, from 5 to 15 miles wide, which extends from the head of St. Georges bay southwestward for 65 miles to the mouth of Little Codroy river (see Figure 1). Several hundred feet of Pennsylvanian rocks overlie rocks of Mississippian age, which are at least 12,000 feet thick. The rocks of the Carboniferous section of Newfoundland are very similar to those of Nova Scotia and represent a northeastward continuation of the same palaeophysiographic conditions. Mississippian measures of Windsor equivalence include thick gypsum deposits which outcrop at many places and which extend under large areas as indicated by sink-holes and by structural considerations.

Jan 1, 1951

By G Pattenden, R Hargreaves, P Pettit

"Even with the cyclic nature of mining, when it comes down to it, the bottom line is that whatever direction the commodity market is going there is always a desire to improve the economics of an operation in order to deliver a greater return to investors. Adapting to market pressures by introduction of an operational process change can often have a downstream impact. What may be less obvious is that reconciliation can play an important part in measuring the effectiveness of many operational changes. Through the adoption of best practice reconciliation and related comparisons, it is possible to measure the impact of changes across the mine value chain and identify variability that may have been introduced. Using analytical business improvement tools, examining and monitoring planned changes can be crucial in understanding whether the introduced changes have been effective and whether they have provided the expected result. Using several case studies, the authors will highlight the benefits provided by modern business intelligence tools, which can provide data validation and accurately report data trends related to both planned and unplanned change events.Citation:Hargreaves, R, Pattenden, G and Pettit, P, 2016. Measuring the Effectiveness of Change through Best Practice Reconciliation, in Proceedings Ninth AusIMM Open Pit Operators' Conference 2016, pp 71–83 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Nov 15, 2016

By Lord Marley

ACTIVE participation by the United States in the war acted as a stimulant on the Annual Institute Meeting in New York rather than a retardant as feared. Attendance was about 10 per cent under the all-time high reached last year, but considering the number of men who could not possibly come because of active military service and the additional number who are devoting their whole time and effort to turning out vital war materials, the registration was really greater than might have been expected. But all in all the Institute put on a show that taxed the capacity of the Engineering Societies Building as well as the capacity of the visitors to find time to attend everything that promised to be of interest.

Jan 1, 1942

By W. Curlook, V. G. Papangelakis, M. Baghalha

A pressure acid leaching process has been developed for the extraction of metal values, nickel, copper, cobalt and zinc, from base metal smelter slags. The basic concept contemplates cooling the smelter slags through solidification sufficiently slowly to induce a good measure of crystallization; and subsequently, after fine grinding, to pressure leach such slags at around 250°C while applying oxygen overpressure, utilizing smelter byproduct sulphuric acid. High levels of extraction of the slags' metal values are thereby achieved. It has been shown that if the same slags are quenched thereby producing an amorphous structure, the resulting metal extractions are very low. The process is applicable to smelting furnace throwaway/discard/dump slags, as well as to in-process converter slags. By extracting the bulk of the residual base metal values in the throwaway/discard/dump slags, the resulting leached residues are rendered virtually benign vis-à-vis the external environment.

Jan 1, 2004

By H Khoshrou, A Siamaki

Blast designs can have productive and non-productive impacts on downstream stages, mine productivity and operating costs. On the other hand, ground vibration, fragmentation, and back break caused by blasting impose damage and financial penalties and which must be controlled by blast design. One of the significant variables in blast design is the burden. In this study, the potentials of artificial neural network are investigated in prediction of burden in the Sungun copper open-pit mine. Input data were assembled through 18 blasting blocks according to different levels and experimental geomechanical investigation. To construct the model blastability index, uniaxial compression strength, hole diameter, specific weight of rock, rock quality designation and cohesion strength are taken as input parameters, whereas, burden is considered as an output parameter. Mean square error was used as the performance function and back propagation algorithm as the training function, containing four hidden layers and 14 data sets. Four sets of data were used to make sure that correct training had been carried out. This produced the coefficient correlation of 0.662.

Sep 26, 2011

Using Positron Emission Particle Tracking (PEPT) to Investigate Industrial Systems

Sep 13, 2010

By L. C. IlsLey, R. A. Kearns

"The electrical section of the Bureau of Mines has obtained copies of all available State safety rules and regulations in order to make a study of those portions of the codes relating to electrical equipment. While it has been found almost impossible to compare the several codes as a whole, comparison of those regulations dealing with a single subject has proved both interesting and instructive.Sixteen states have rules or enactments having reference to telephones and the present paper covers a compilation of these references. It is believed that data of this kind will be of service to commissions or other bodies contemplating the revision of existing codes.The compilation taken from the various codes follows: State Rules and Regulations.California.Sec. 5 (Par. c) Telephone communication shall be maintained between a co-operative station and each mine which it supplies. If the foreman in charge of a station does not reside thereat, his residence also shall be in telephone communication with each mine supplied by his station.Sec. 8 (Par. a) Whenever a fatal accident occurs in or about any mine, notice thereof shall be given promptly by telephone or telegraph if possible, followed by a notice in writing to the chief inspector, by the superintendent or other person having immediate charge of the work at the time of the accident."

Jun 1, 1921