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By S G. Li

Mine intelligent ventilation is an important guarantee to realise intelligent mining. It is the integration of the Internet of Things, big data, artificial intelligence, internet, cloud computing with ventilation technology, forming a complete ventilation system with intelligent perception, intelligent decisionmaking, intelligent emergency response and airflow control. In order to fully grasp the progress and trends of mine intelligent ventilation research in western China. The paper based on literature analysis and field application research, comprehensively expounds the main research and practical results of mine intelligent ventilation in western China, mainly analyses the development status of key technologies such as accurate and rapid determination of mine ventilation parameters, intelligent analysis and decision-making of ventilation and intelligent regulation of ventilation equipment, and introduces the field test or application of mine intelligent ventilation technology in western China. It lays the foundation reference for related research and improving the intelligent level of mine ventilation.

Oct 12, 2022

By C A. Foss, D A. Clark, D Hillan

While magnetic surveys are the most common geophysical method used in mineral exploration, magnetics and geology remain to be fully integrated quantitatively in iron ore provinces. Although high-resolution aeromagnetic data has been collected over prospective areas of the Hamersley Province, much of the information in the data sets has hitherto not been fully exploited due to a lack of suitable interpretation methods. Recent advances in the processing and modelling of magnetics in highly magnetic terrains, constrained inversion and 3D visualisation and understanding the magnetic properties of banded iron formations and iron ores potentially create the capability to generate realistic 3D mapping of magnetite and hematite concentrations over large areas. Initial processing of conventional total magnetic intensity data produces true potential field maps that are unaffected by local perturbations of the regional geomagnetic field direction by intense local anomalies. The true potential field can be converted into vector and tensor components, each of which emphasises different structural features of the geology. Scalar quantities derived from these components simplify interpretation, using new methods, developed by CSIRO and elsewhere, that are less sensitive to magnetisation direction. Preliminary interpretations allow interpolation between mapped units and structures and evaluation of remanence and anisotropy effects. Accurate modelling requires rigourous treatment of self-demagnetisation and magnetic interaction effects. Semi-automated constrained inversion, combining magnetics with available geological information and other geophysical data, can be utilised to generate models of disposition of major magnetic units and the 3D magnetisation distribution within them. The final stage of interpretation is to exploit the understanding of magnetic properties (susceptibility, anisotropy and remanence) developed over many studies by CSIRO, the University of Western Australia and others to convert the interpreted magnetisation distributions into 3D maps of magnetite and hematite contents, which are the quantities of direct exploration interest.CITATION:Clark, D A, Foss, C A, Austin, J and Hillan, D, 2015. Three-dimensional mapping of magnetite and hematite concentrations from reprocessing of detailed aeromagnetic data, in Proceedings Iron Ore 2015, pp 229–240 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By Napitupulu P

PT Freeport Indonesia currently operates a concentrating complex capable of milling 127 000 metric tonnes per day of copper and gold hearing ore. The facilities consist of both a conventional crushing, ball mill and flotation circuit and a SAG, ball mi

Jan 1, 1997

By E. H. Illsley

This bibliography is the first report of a Bureau of Mines research project on thermoelectric materials. Interest in such research has increased because of recent success in the design of commercial products, including generators and refrigerators, using the principles of thermoelectricity. This success made possible by the discovery of semiconductors that have much higher [effincies] than the metals and alloys formerly studied. Thermoelectricity is a term that includes a large number of phenomena relating heat to electrical energy. However, the moat important applications arise from two effects discovered by Seebeck in 1822 and by Peltier in 1834. When pieces of two unlike materials are joined at their two ends to form a continuous circuit, both of these effects may be observed. If the two junctions are maintained at different temperatures, an electromotive force known as the Seebeck voltage is generated. If, on the other hand, a current is made to flow through the circuit, the junctions of the materials will be found to differ in temperature. This phenomenon is called the Peltier effect.

Jan 1, 1959

By Richard N. Appling

This compilation presents information obtained through investigation of manganese deposits and a reconnaissance of potential manganese-bearing areas of southwestern Oregon and Del Norte County, Calif., from October 1952 to September 1955. The report includes maps, assays, and preliminary examination data on 39 manganese deposits distributed throughout Curry, Coos, Douglas, Josephine, and Jackson Counties, Oreg., and 1 deposit in Del Norte County, Calif. On the basis of mineral content the deposits can be divided into three groups: 1 Manganese silicate deposits, manganese oxide deposits, and manganiferous iron de-posits. Generally the oxides occur along the coast in the Curry-Coos County area, the manganiferous iron deposits are in the Josephine-Douglas area, and the manganese silicates are found in both the Josephine-Douglas and Jackson County areas. The deposits are characteristically irregular in form and usually small. Most silicate and manganiferous iron deposits are in metasediments of Triassic (?) age; oxide deposits are in sediments varying in age from Jurassic to Eocene.

Jan 1, 1957

By Erico Tabosa, Kym Runge, Peter Holtham

"The distribution of turbulence in an industrial scale mechanical flotation cell and its effect on flotation kinetics was studied using a fully instrumented 3m³ cell. The cell was operated at a copper concentrator in Australia with different combinations of airflow rates, impeller speeds and sizes and cell aspect ratio providing a wide range of hydrodynamic conditions. An analysis of the overall flotation cell performance showed that the overall copper recoveries were very similar for the conditions tested. However, by decoupling pulp effects from froth effects it was possible to evaluate whether the changes made affected the pulp zone and/or froth zone responses. The analysis showed that the overall recovery has the potential to be up to 7% higher, if not limited by froth recovery. The cell hydrodynamics were characterised by the overall energy dissipation rate and, to understand the distribution of turbulence within the cell, localised measurements were made using a piezoelectric vibration sensor. By comparing the metallurgical performance of the cell with the different hydrodynamic conditions it was found that the collection zone flotation rate constant was not directly related to overall energy dissipation, as is commonly observed at laboratory scale, where energy is usually only changed by varying impeller speed. In this study, energy dissipation rate was varied using not only impeller speed, but also the size of the impeller and the cell aspect ratio. In these circumstances, the best correlation was found to be between the collection zone flotation rate constant and the distribution of turbulence, i.e. the size of the turbulent zone."

Jan 1, 2014

By Theodore Kootz

Manufacture of high-grade ferromanganese; as a rule; requires a low-phosphorus-manganese ore with 45 to 55 percent Mn, chiefly obtained in the Soviet Union, the British Dominions, and Brazil. Also, low-manganese ores have already been used for ferromanganese production, especially in North America .and Germany. During World War I, a process was developed in which a high-phosphorus ferromanganese or spiegeleisen was prepared in the blast furnace from law- or high-phosphorus manganiferous ores, then low-phosphorus manganese slag was prepared by refining under an acid slag, and this material was, worked into a low-phosphorus ferromanganese in the blast furnace.9/ Manufacture of useful manganese ores from a phosphorus-bearing spiegel with 12 to. 15 percent Mn, 4.5 percent C,, and 0.5 percent P by slagging in a refining furnace was reported by Joseph, Barrett, and Wood.10/ The spiegel was refined to 0.75 percent Mn, 3.4 percent C, and 0.45 percent P. Thereby, a slag with about 43 to 58 percent Mn and, about 10 percent Si02, was obtained. Hotter melts gave a smaller phosphorus content in the slag than cold melts. In addition, the phosphorus content of the slag varied with the manganese content of the intermediate metal.

Jan 1, 1952

By Edmund S. Leaver

[In previous reports 5/ of ore-testing studies standard methods of conduction tests with precious-metal ores selected as representative of certain mining districts were discussed in considerable detail.]

Jan 1, 1941

By Tulu B. Ihsan, Mark A. Van Dyke, Ted M. Klemetti

"How well do current modeling procedures calculate the rear abutment extent and loading? Does an improved understanding of the rear abutment extent warrant a change in standing support in bleeder entries? What is the optimal standing support for bleeder entries separated from the longwall startup room by a barrier pillar? To help answer these questions and to determine the current utilization of standing support in bleeder entries, four bleeder entries at varying distances from the startup room were instrumented, observed, and numerically modeled. This evaluation was intended to determine the rear abutment extent and magnitude at various locations to optimize standing support in these entries and those under similar conditions. This paper details observations made by NIOSH researchers in the bleeder entries of a deep cover longwall panel; specifically data collected from instrumented pumpable cribs, observations of the conditions of the entries, and numerical modeling of the bleeder entries during longwall extraction. The primary focus was on the extent and magnitude of the abutment loading experienced by the standing support. As expected, the instrumentation of the standing supports showed very little loading relative to the capacity of the standing supports—less than 25 tons load and 1 inch convergence. The observations of the conditions showed little to no change from before the longwall panel extraction began to when the panel was more than 50% extracted. In addition to the observation and instrumentation, numerical modeling was performed to evaluate the bleeder design. The Flac3D program was used to evaluate these four bleeder entries using previously defined modeling and input parameter estimation procedures. The results indicated only a minor increase in load during the extraction of the longwall panel. The model showed a much greater increase in stress due to the development of the gateroad and bleeder entries, with about 80% of the increase associated with development and 20% with longwall extraction. The Flac3D model showed very good correlation between expected gateroad loading during panel extraction and those expected based on previous studies. The front and side abutment extent modeled was very similar to observations from this and previous panels with similar conditions. The results of this study showed that the rear abutment stress experienced by this bleeder entry design was minimal. The convergence measured in these bleeder entries was small enough not to mandate any additional support beyond development even by U.S. or Australian standards. The pumpable crib load and convergence experienced depends on the geological setting, mining geometries, and timing. The farther away from the startup room, the lower the applied load and smaller the convergence in the entry if all else is held constant. Finally, the numerical modeling method used in this study was capable of replicating the expected and measured results near seam."

Jan 1, 2017

By Dan Ifrim, Andre Solecki

Tunneling could be a major challenge to tunneling contractors as tunneling operations can be seriously affected by the Tunnel Boring Machine (TBM) performance. Specifying the appropriate TBM methodology, selection of systems and features, is critical for managing tunnel risks and contribute to successful tunneling project. The paper analyzes tunneling records from the recently completed City of Toronto’s Ashbridges Bay Treatment Outfall tunnel project and underlines the righteous selection of the TBM type and associated TBM systems in achieving good advance rates during tunnelling and managing project risks. The paper intends to draw attention of a few aspects of TBM technical specification importance and highlight the lessons learned from this process.

Jun 13, 2023

By J F. Carswell, G Cheshire

The Pajingo gold operation in Queensland is approximately 55 km south of Charters Towers and 134 km south-west of Townsville. The gold deposit was discovered on the northern end of the Drummond Basin in 1983 and first open pit production began in 1986. Mining progressed underground in the 1990’s and gold production peaked in the early 2000’s as the main Vera/Nancy lodes were extracted, producing 330k oz in 2003 (a record at the time). More recently, as Ore Reserves and grade have diminished, the mine has had to develop innovative mining practices to maximise recovery of the remaining Mineral Resource. This has included a modified sublevel caving method against previously mined/backfilled zones. The method has been coined modified sublevel shrinkage (MSLS). Full scale trials of the new mining method have been successfully completed. This has allowed the site to revaluate the Mineral Resource and include areas into the Ore Reserve that were once deemed sterilised, adding significant value to the operation and extending its life-of-mine. This paper describes the first of two large scale MSLS trials and key operational learnings from it.

Mar 15, 2021

By W. M. Williams

"Although manganese is a metal virtually unknown to the layman, it is hardly necessary to point out to the engineer the importance of manganese in modern metallurgy, an importance intimately linked with iron (and steel), the basic materials of engineering construction for hundreds of years and certain to remain so for long into the future. World steel production will approach and perhaps reach 1 billion tons/year in the 1980s; with a manganese content between 0.5% and 1 % in ordinary steels, and more in specialty steels, manganese use worldwide will soon approach 15 million tons annually. Manganese was discovered and isolated in Sweden in 1774 by Karl Wilhelm Scheele (who also discovered molybdenum), but the element was only of scientific interest for several decades. By the early part of the nineteenth century, however, manganese oxide had become commercially available and was in use for colouring glass and for the production of chlorine. Commercial application in metallurgy appears to have been limited to the manufacture of crucible (or ""cast"") steel, a highquality product made by carburizing wrought iron, and melting it in small batches to make ingots which could be rolled and used for special applications, e.g. for the manufacture of fine tools or for ""steeling"" the cutting edges of implements such as wrought iron axes and chisels.* However, it was not until Bessemer's epoch-making invention of cheap steel in 1856, and the dramatic expansion of the steel industry thereafter, that manganese assumed the importance that it holds in modern steelmaking."

Jan 1, 1999

By H. Dreissen

Upgrading of low-concentration ores is of growing importance today. The Heavy Medium Cyclone Process, thanks to strong centrifugal forces, effectively separates particles varying only slightly in specific gravity but widely in size. The paper discusses the separation efficiency, the method of assessing that efficiency, and the influence of such factors as medium solids. The operating results of nine heavy medium cyclone plants handling following minerals are reported: barite, wolfram, iron, magnesite, diamond, lead-zinc, fluorspar, rocksalt potash. Highlighted are an improved recovery system for heavy medium and some other developments, such as techniques for separation down to 0.1mm and the application in the field of recycling.

Jan 1, 1980

By P. Guliov

In the first part of this paper the authors present an overview of industrial minerals produced in the Canadian provinces of British Columbia, Alberta and Saskatchewan, and supplied to the Pacific Rim countries. The second part outlines some of the unique opportunities for industrial minerals that exist in the three western Canadian provinces and those minerals we feel have development potential for overseas markets. Because of time constraints, it is not an exhaustive presentation on industrial minerals, but is focused on a few selected minerals that we believe have high potential.

Jan 1, 1990

By G. G. Eichholz

SUMMARY RADIOACTIVE dynamite has been prepared by introducing a small amount of antimony-124 into the explosive. Test work is described on the effectiveness of this tracer, on radiation levels in its neighbourhood, and on different methods of .application. Factors determining the choice of isotope, amount of activity, and overall cost of this process are discussed. INTRODUCTION Instances are known in which dynamite remains unexploded in drill holes in mining operations. Usually such 'bootlegs' are easily located by inspection of the face and the powder is removed before subsequent drilling is started. Occasionally, however, serious accidents occur because workmen drill into an undetected piece of dynamite. In order to avoid such accidents it was suggested that a different method of location might be tied, such as that afforded by the use of radioactive tracers. This paper describes some experiments that were carried out under the auspices of the Department of Mines and Technical Surveys, with the active co-operation of Canadian Industries Ltd. and Canadian Refractories Ltd., to test the feasibility of such a scheme.

Jan 1, 1957

By M. Giralico

Optimized mixer settler designs will now handle flows of over 25,000 GPM. The size and expense of the equipment hamper experimental settler optimization efforts. Computational Fluid Dynamics (CFD) is a timely and predictable tool for settler design development. In the past, CFD has been used to evaluate only the flow field in pumped and auxiliary tanks. A similar numerical analysis is used to evaluate settler flow and phase separation. Phase separation is analyzed using multiple species for the aqueous and organic phase. Experimental validation shows good agreement between the computational and experimental solutions in both flow field and phase separation. The computational model is used to show performance differences between various choices of settler geometry, liquid depth, with variable flow rates. Understanding the differences allows the development of optimized settler designs. System improvements are predicted to lower entrainment levels further and/or allow new smaller footprint designs. This paper focuses on the major design components of the settler and how future technological advances will lead to further improvements in their design. LIGHTNIN?s new designs will handle tomorrow?s production requirements, while maximizing profits.

Jan 1, 2003

By Harsh Kumar Verma

Blasting off-the-solid is the most commonly used method during development of galleries in Bord and Pillar method of underground coal mining. In this method, only P5 explosives are used with permitted delay detonators in accordance with the safety requirements stipulated by the regulatory bodies. Delay detonators made with pyrotechnic delay compositions have inherent scattering in their delay timings. It is desirable to use precise detonators to achieve better fragmentation, less vibration and noise. Overlapping of delay period is undesirable from production as well as safety point of view.

Jan 1, 2008

By Derek J. Barratt

The existence of a critical size buildup in an autogenous or SAG mill can be predicted from proper examination of drill core and ore samples. Methods of dealing with such critical size in a primary mill are reviewed in the context of ore properties, whether or not pilot plant-scale testwork has been conducted, and also with respect to the design of new plants or the retrofitting of existing operations. The implications of not planning for pebble crushing in situations where it is appropriate are discussed.

Jan 1, 1992

Spent automobile catalyst is an important secondary resource of PGMs (platinum group metals) and the recovery is significant. Various methods of recovery technology have been reported and applied in practical production, including pyro- and hydrometallurgical processes. Since the grade of PGMs in the catalysts is so low, approximately 0.5 wt. %, the present recycling technologies require high energy-consumption, it is of great significance to enrich the PGMs with some energy saving physical separation methods as a pretreatment. Automobile catalyst is usually composed of cordierite phase as a substrate and alumina phase, with PGMs, which covers the cordierite phase. We adopted the quenching pretreatment, one method of thermal shock, to generate micro-cracks between the two phases and separate the alumina phase from cordierite. Quenching was carried out by heating the catalysts in an electric furnace of different temperatures followed by rapid soaking into cold water. It was found that the phase boundary between alumina and cordierite was broken in the quenching and selective separation (detachment) of alumina from the cordierite could be achieved in the following surface grinding. The effect of quenching was checked by microscopic observation, hardness measurement, and chemical analysis. This paper figures out the stress formula of the quenching process, which is largely connected with layer thickness and temperature gradient by using an FEM (Finite Element Method) simulation and clarifies the mechanism of crack generation in the quenching process. Keywords: automobile catalyst, PGM, quenching process, FEM

Sep 1, 2012

In many base metal sulphide concentrators reagents such as collector and cyanide are often added to the grinding mill as well as to the flotation circuit. Whilst good reasons can be cited for splitting the reagent addition in this way, the benefits of such are rarely quantified and the complex reagent-mineral-media interactions occurring during milling are often poorly understood in terms of pulp chemistry. A new laboratory batch grinding mill designed by Magotteaux allows the user to measure, monitor, and control the pulp chemical conditions during grinding when testing different ores and media. Some of these parameters include pulp pH, pulp Eh, temperature, gaseous atmosphere, and dissolved oxygen concentration. In a recent development, the mill has been coupled with a simple on-line reagent monitoring system, designed by CSIRO, which allows the levels of species such as xanthate and cyanide in the grinding pulp to also be measured continuously during milling using a robust UV detection system. In this way the uptake of collector during grinding and the rate and ex-tent of cyanide interaction with the minerals and media can be determined as a function of grinding time. A series of grinding tests using an Australian nickel sulphide ore was conducted with the coupled system in which the cyanide dose, xanthate dose, and media type were systematically varied. The xanthate and cyanide levels were monitored as a function of grinding time and the data collected are discussed in terms of the pulp chemistry of the system and implications for plant reagent dosing strategies.

Jan 1, 2014