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By C. Marais

The use of machine vision in the monitoring and control of metallurgical plants has become a very attractive option in the last decade, especially since computing power has increased drastically in the last few years. The use of cameras as a non-intrusive measurement mechanism not only holds the promise of uncomplicated sampling but could provide more consistent monitoring, as well as assistance in decision making and operator and metallurgist training. Although the very first applications of machine vision were in the platinum industry, no automated process control has been developed for platinum group metals (PGMs) as yet. One of the reasons is that to date froth features could not be related to key performance indicators, such as froth grade and recovery. A series of laboratory experiments was conducted on a laboratory-scale platinum froth flotation cell in an effort to determine the relationship between the platinum grade and a combined set of image features and process conditions. A fractional factorial design of experiments was conducted, investigating 6 process conditions, namely air flow rate (x1), pulp level (x2), collector dosage (x3), activator dosage (x4), frother dosage (x5) and depressant dosage(x6), each at levels. Videos were recorded and analysed to extract 20 texture features from each image. By using artificial neural networks (ANN), the nonlinear relationship between the image variables and process conditions and the froth flotation grades could be established. Positive results indicate that the addition of image features to process conditions could be used as sufficient input into advanced model based control systems for flotation plants. Keywords Flotation, machine vision, image analysis, neural networks.

Jan 1, 2011

By T. Lux, M. Hanel, Degel, A. Filzwieser, R., H. Joubert

It is the increasing demand for an economic and cost saving operation mode that requires effective cooling in order to achieve low refractory wear and good furnace lifetime, which is making cooling technology an important aspect of furnace operation. In addition, the requirements for safety are getting more and more into focus. However, the use of water—today’s standard cooling medium—has major drawbacks as it can cause problems both during furnace start up and operation, namely hydration problems, corrosion, and explosion. Not to forget the severe risks for the operators as well as economical damage in case of a malfunctioning water cooling system. With this new and patented cooling technology ILTEC and the ionic liquid IL-B2001 as the cooling medium, it is possible to realise a water-free cooling solution and therefore the door is wide open to rethink existing and conventional cooling solutions. Furthermore, there is also the chance to recover heat from the process in a more efficient way. However, since the technology is novel and unique there are a lot of concerns and doubts regarding safety for plant operators and employees. The paper is intended to cover both: highlighting the enormous potential of the technology but also to eliminate concerns mainly caused by rumour and unawareness. INTRODUCTION All of us are aware of the risks when water is used as a coolant and placed in the vicinity of the liquid metal phase. Unsuitable design solutions or wrong operation modes of the furnaces or failures of refractories can cause a direct contact of water with liquid metal. The consequences can lead to equipment failures, vessel destruction but even worse to injuries and even fatalities. Over the past decades, countless incidences were reported. Fatal accidents caused by water coming into contact with liquid metal happen every year (Oterdoom, 2014; Filzwieser, Konetschnik, Filzwieser, Wallnerm & Preiss, 2014). With the novel ionic liquid cooling technology virtually all negative effects of a water cooled system regarding safety are eliminated and even additional benefits can be provided (Voermann, Ham, Merry, Veenstra, & Hutchinson, 1999;Verscheure, Kyllo, Filzwieser, Blanpain & Wollants 2006; Wallner, Filzwieser & Kleicker 2006). The fact that no explosion occurs when IL-B2001 gets in contact with molten metal results in a revolutionary solution for the metallurgical industry in terms of safety—new safety standards can be achieved.

Jan 1, 2019

By James C. Barker

Unverified reports of rare earth element (REE) concentrations in gold placers and radioactive mineral prospects in the Zane Hills were investigated by the U.S. Bureau of Mines as part of the Alaska critical minerals program. REE is reported to occur in dredge concentrates at the Hogatza mine and up to 1.2 pct REE was previously analyzed in alkalic syenite (bostonite) dikes marginal to the pluton. In addition, numerous thorium-rich veins, explored for their uranium content but unevaluated for REE, occur on the western margin of the Zane Hills. The Bureau mapped and sampled all of the reported or suspected REE occurrences. Dredge concentrates contain abundant uranothorianite, a mineral species which incorporates cerium subgroup REE. Bostonite dikes occur in conjunction with a multi-phased zoned alkalic intrusion, however, no significant REE concentrations were found. Thorium-rich veins contain nil to 0.5 pct Y but resource potential is limited by this relatively low grade, the ultimate low tonnage potential, and the lack of uranium as a major economic element. The Zane Hills exhibit attractive exploration targets for uranium deposits, primarily in a sedimentary form. Gold may be found peripheral to the pluton in both placer and lode deposits. Resource potential of REE, however, appears limited to a placer by-product of REE-Zr-Ti that is recoverable only during large scale gold placer mining. Placer exploration of the lower Wheeler and Dakli Creeks is suggested.

Jan 1, 1991

By Frank B. Fulkerson

This is the second of two interrelated studies of waterborne transportation. The first study discussed transportation of mineral commodities on the inland waterways of the South-Central States.2 Together, the two surveys describe and analyze the flow of foreign and inland waterborne commerce of the gulf coast. All the principal mineral-industry imports and exports of the gulf coast are mentioned in the report, including metals, nonmetals, and mineral fuel products, The gulf coast foreign trade in mineral industry products was determined to be composed of a small number of commodities.

Jan 1, 1971

By L. Clark

Despite near-record commodity prices, the mining industry continues to search for ways to maintain profits in these times of steadily increasing energy prices and steadily decreasing grades. The pressure is still on today’s miners to continuously improve their operations because they know that one day prices too will drop. Some, however, have seized the opportunity to employ systematic methods to reduce costs and increase the efficiency of their workforce and equipment. As a result, closer attention is being paid to scheduling and the value that could be added by defining the extraction sequence that maximizes the net present value [NPV] of a project. This paper will discuss the challenges faced by Newmont Mining Corporation [Newmont] at its operations and the application of sophisticated software tools and methods in its search of solutions to this problem.

Jan 1, 2007

By Charles S. Barrett

NUMEROUS determinations1-7 of the tex-ture of cold-rolled polycrystalline iron, steel, and ferritic alloys have been made with good agreement among the various observers as to the principal features of the texture common to all, but there has been no adequate explanation of the texture in terms of the behavior of individual grains. This study presents an explanation of the texture based on the observed rotation of single crystals when deformed in a manner similar to a grain in the aggregate, a method we have found useful in leading to a better understanding of compression and tension textures;8,9,10 in particular, the aim has been to determine experimentally the end orientations of rolled single crystals of iron. These are discussed in connection with the point of view of Wever1 and of Boas and Schmid2 that the rolling texture is a simple compression texture (compression normal to the rolling plane) superimposed on a simple tension texture (tension in the roll-ing direction), and the point of view of Kurdjumow and Sachs3 that three ideal end orientations exist.

Jan 1, 1940

By F. E. Harris

The United States produces about 30 percent of the world output of salt. Numerous deposits occur in widely separated areas, but the leading producing States are California, Kansas, Louisiana, Michigan, New York, Ohio, Texas, Utah, and West Virginia. Although no great amount of salt is produced at present in Pennsylvania, the potential sources in that State recently aroused a good deal of interest. The United States salt industry is highly organized; it comprises fewer companies than when small crude works with primitive methods and equipment eked out salt for local needs, but concentration of output brought about by modern inventions and methods of production has improved the quality of the produce greatly and accelerated production.

Jan 1, 1939

By Travis Q. Lyday

During 1981, Ecuador's gross domestic product (GDP) increased by a reported 4.8% in real terms, a slight improvement over that of 1980. In current prices, the CDP in 1981 was estimated at $13.7 billion.2 The inflation rate increased to 15.6% according to official figures, above that of 1980. Ecuador's production of petroleum increased 3% in 1981 compared with that of 1980. The consortium of Corporación Estat al Petrolera Ecuatoriana (CEPE), the state oil company, and Texaco, Inc., produced almost 98% of the total from their Putumayo Basin operations in Oriente, the eastern jungle region. In sharp contrast, output from the Santa Elena Peninsula Fields, where oil was first produced commercially in 1921, continued to decline, producing only 510,000 barrels, a decrease of almost 8% compared with that of 1980.

Jan 1, 1983

Experiments in the bolting of a mine roof were commenced at Elrington Colliery on the South Maitland Coal Field early in 1949, following the appearance of an article in the American publication, "Coal Mine Modernisation Year Book" 1948. Prior to this, although bolting had not been used in the maintenance of satisfactory roof conditions, the principle of roof bolt anchorage had been illustrated in instances such as the hanging of a trolley locomotive power wire using an expanding shell type of bolt anchorage, or the insertion of an eye bolt with a split and wedge, as used to suspend a rope block over a winze being sunk in a metalliferous mine.The experiments at Elrington Colliery were the first efforts in this country to supplement the work of timber supports under a mine roof with systematic placement of roof bolts.Following the series of experiments at Elrington, full scale bolting was commenced at that Colliery in a trackless mobile section in April, 1950.The obvious success of the system at Elrington indicated that it might also be a success in the support of weak roof strata immediately overlying the workable section of the Victoria Tunnel Seam at John Darling Colliery.The system was commenced at John Darling Colliery in April, 1951, in one mechanical section on the Victoria Tunnel Seam, and the scope was gradually widened until by December, 1952, ail'six mechanical units then operating on this seam were working under bolted roofs.

Jan 1, 1954

By J Harris, J Turner, P Kirsch

Coal mining is recognised globally as a hazardous activity, and as a result operates under high levels of regulatory and public scrutiny while managing a workforce operating in a high-risk environment. Mining companies have developed sophisticated risk assessment procedures, management systems and personnel competency requirements that facilitate the safety and health of employees, and Australia is a world leader in coal mining safety and health.RISKGATE is an Australian Coal Association Research Program funded online platform that delivers broad cross-industry knowledge about current practice in the identification, assessment and management of coal mining risk. Centennial Coal has engaged with the RISKGATE program, managed by the University of Queensland’s Minerals Industry Safety and Health Centre, since its inception in 2010, and contributed topic experts to many modules, including underground topics within the geological and geotechnical domain (strata underground, outburst, coal bumps and bursts, and inrush).In 2013, Centennial Coal experienced significant unexpected strata failure at the Mandalong mine without any personal injury or fatality. This paper presents a case study in the application of RISKGATE to management of this unwanted event, the steps that were implemented, the information that was sourced and the contribution that RISKGATE made to the final outcomes. The Australian coal industry is encouraged to embrace our knowledge platform, and to also openly share processes and practical outcomes that result from integration of RISKGATE in mining operations.CITATION:Harris, J, Turner, J and Kirsch, P, 2014. Case study – application of RISKGATE to managing strata failure in an Australian coalmine, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 55–60 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

The Precambrian Eastern Creek Volcanics comprises spilitic basalts with interbedded sediments and tuffs which were extruded and deposited during Middle Proterozoic time. The rocks have undergone low-grade regional metamorphism.The Eastern Creek Volcanics are approximately 17,000 ft thick and have been divided into four units.The rocks were laid down in a geosynclinal basin elongate to the north. The main structural features are the northerly trending Mount Isa and Gorge Creek-Quilalar fault systems.Major east-west faults cause repetition of the sequence.Copper and uranium mineralization is known within the formation. Copper mineralization is confined to quartz-filled shears anp basalts. Nothing of economic importance has been found in the area though ore deposits have been found elsewhere in this type of environment.

Jan 1, 1968

By J. Ran

There are challenges in mining deep tabular ore deposits using the open stoping method, particularly mining remnant panels towards the end of mine life. The remnant panels have experienced stress concentration and are in the failing or post failure state causing drilling and loading difficulties, ground movement, induced seismicity and ground instability problems. As more mines are going deep, without effective ground control management, the mine production will be interrupted and equipment damage and personnel injury are likely to occur. Mining at Falconbridge Lockerby Mine located in the Sudbury Basin was concentrated in the deep zone from late 1990s to 2004. The remnant panels situated approximately from 1800m to 1920m below surface were mined in 2004 before the mine closure. These panels were in the central section of the orebody along strike. The orebody was relatively narrow ranging from 5m to 15m and steep dipping at 70o to 80o. Because of the retreat mining sequence and the mining depth, stress concentration, wall closure and seismicity had caused a number of mining difficulties. Managing these challenges was critical in achieving the mine production target without compromising personnel safety and excavation stability. A comprehensive ground control management approach was adopted to mine the remnant panels at depth. The measures taken included ground movement monitoring, understanding the movement pattern of the footwall rock and selecting appropriate support systems, analyzing seismic monitoring data and defining re-entry protocol, brow support design and restricting access. This paper presents these ground control measures and the experience gained in successfully mining the deep remnant panels at Lockerby Mine.

Apr 1, 2005

By Walter D. Holland

This is one of a series of instruction guides developed to help instructors present health and safety training courses to workers in the metal and nonmetal mining industry. This course is intended for training those, usually the safety officers, who perform surveys for inhalation contaminants in above ground work areas. The handbook entitled ?Handbook for Surveys of Inhalation Contaminants in Above Ground Metal and Nonmetal Mining and Processing Work Areas? is used as a manual for the course and as a prime reference when performing the actual surveys or interpreting the sampling results. There are six experiments for the students to perform during the course to familiarize them with the sampling devices routinely used during the surveys.

Jan 1, 2011

By M. S. Fleming

The objective was to evaluate central lubrication systems for potential use on underground mining equipment. Previous use on continuous mining equipment resulted in poor system performance because of improper selection of lubricants, component failures, and an inconsistent delivery of lubricant to the bearings. The principles and operational characteristics of systems are reviewed and evaluated, and it was concluded that systems are available which can provide reliable central lubrication if properly applied, installed, and maintained. The procedures for applying a system to a continuous miner are discussed. Investigation revealed the lack of significant information on lubrication-related equipment failures and injuries related to maintenance and repair operations, the lack of significant failure rate data for central lubrication system components, and the lack of performance standards for central lubrication systems and components. To continue the development of systems for underground mining equipment it is recommended that a data bank on failures and reliability for equipment with and without central lubrication systems be created, and standardized specifications and performance criteria be developed for central lubrication systems and components which will be used on underground mining equipment.

Jan 1, 1979

By Sam S. Taylor

[The discovery of many oil fields in Illinois since 1936 and their rapid development have brought tine problem of brine disposal to the foreground in that State. The ultimate magnitude of the is not yet known, but already it is great enough to warrant technical investigation. The Bureau of Mines, therefore, has made a general survey of the methods of handling oil-field brines in Illinois and has studied in detail three subsurfaces disposal systems.]

Jan 1, 1940

The solvent extraction section of an old Uranium Plant in the Vaal River region (North West Province in South Africa) produced a substance called CRUD (Chalk River Unidentified Deposit) that formed within the aqueous/organic interface of the settler of the solvent extraction circuit. The CRUD was deposited together with gold tailings to the tailings dam many years ago. Previous research done on the CRUD confirmed that exposed CRUD leaches Mn and Ni at concentrations that are well above their acceptable risk limits as well as Zn that leaches at concentrations that are slightly lower than its acceptable risk limit. Soil washing and bioremediation technologies were employed to treat the contaminated soil.   Various laboratory test work and the pilot scale studies were conducted in parallel with each other and the results of the laboratory studies were used to determine critical parameters. Four lixiviants, ie sulfuric acid, acetic acid, oxalic acid and ethylene diamine acetic acid were tested at three concentration levels ie 0.001 M, 0.0001 M and 0.00001 M, respectively. Column tests showed that the leaching of the heavy metals increases as the soil porosity increases. Silica sand was added to increase porosity of the contaminated soil. Highest Mn removal was achieved mainly by sulfuric and oxalic acid at 0.001M at all soil levels. EDTA was significantly efficient in the removal of Ni and Zn. The recovery of heavy metals, particularly Mn, decreased as the depth of sampling increased.   Heterogeneous bacteria and filamentous organism plate counts were conducted to evaluate the growth of the bacteria and filamentous organisms in the soil. Results showed that more organism growth took place in the bioremediated soil with a fertilizer added to it. The leaching of metals from the soil that was bioremediated in the pilot study was generally higher than the extraction of the metals from the soil that was leached with no bioremediation carried out. The results from this study suggest that the leaching of heavy metals from the contaminated soil is to a large extent dependant on the pH of the leaching solution. By increasing the soil's porosity and bioremediating the soil, higher extractions of metals were achieved.

Jun 1, 2010

By J. T. Popp

This Bureau of Mines study reviews the geological factors that affect methane in the Beckley coalbed in southern West Virginia, including overburden, coalbed structure, type of and changes in lithology above and below the Beckley coalbed, and presence of fractures in the coal and rock adjacent to the Beckley. Depending on the depth, the Beckley coalbed emits from 216 to 520 ft3 of methane per ton of coal mined, and the Bureau estimates that methane emission in a deep, extensively developed mine in this area may exceed 3,000 ft3 per day per ton of coal mined. Average face cleat and butt cleat trends in the Beckley coalbed measured underground are N 33° W and N 53° E, respectively. Close cleat spacing con¬tributes to the friable nature of the Beckley and provides easy movement for methane and water. Because rider coals, splits, and carbonaceous shales may contribute methane to mine emissions, predictions of methane emission based on gas content of the Beckley coalbed alone may be conservative. Beckley coalbed reserves in the study area are 234 million tons. The gas content of the Beckley coalbed averages 407 ft3/ton, and the coalbed gas reserves are 108 billion ft3.

Jan 1, 1976

By Robert Stefanko

The growing demand for energy during the post World War I and World War II periods has prompted underground coal production to increase rapidly. This has been met primarily by mine mechanization, resulting in the development and application of new mining machine types. Correspondingly, the total connected horsepower of each machine as well as the number employed has enlarged rapidly since 1950. (2,3,9,14,16,17) Electrical consumption for each mine has also grown. In the early years of mining electrical applications, only d-c power was utilized underground. Yet, d-c machine limitations were soon realized, and many a-c systems were substituted to permit economic and efficient utilization of a-c distribution and motors. Due to the attractive torque characteristics, ease of distribution and speed control, several traction applications have continued to be powered by d-c motors. The result has been the now prevalent use of mixed a-c/d-c mine power. However, augmented electrical power employment seems to have added to underground coal mining electrical accidents.

Jan 1, 1974

By S. A. Osterberg, J. L. Breckenridge, R. S. Popielak

Multidisciplinary investigations were completed to prove the availability of water resources for the proposed San Cristóbal silver-lead-zinc mine in the arid Altiplano of Bolivia. Surface water resources are scarce, of poor quality, and unsuitable for development. Therefore, hydrogeological reconnaissance targeted alluvial aquifers for development. Follow-up resistivity, refraction, and water quality assessments were used to prioritize areas with prolific production potential. Pumping tests and regional water balance analysis indicate an alluvial aquifer can sustain the required approximately 40 000 m3 per day production for the life of the mine and predict no significant negative environmental effects on local groundwater users and the environment.

Jan 1, 2002

By John Babcock, Bryan C. Smith

In a partnership between Luck Stone Corporation and Loudoun Water, a 42” (1.067m) steel pipeline was constructed along the perimeter of an extensive permitted reserve of diabase rock Luck Stone was about to begin mining. Loudoun Water provides drinking water and wastewater services to over 75,000 households in Loudoun County, Virginia. In discussions to establish the 30-foot (9.1 meter) easement for Loudoun Water within the permitted reserve of diabase rock, Luck Stone and Loudoun Water agreed on the following basic conditions: • Luck Stone could execute production blasting as close to the easement as physical conditions of overburden depth permits. We estimated the minimum distance to be about 75-feet (22.86 meters) from the centerline of the pipe. • Loudoun Water would install strain gauges on the pipe every 500-feet (152.4 m) along the entire length of the future reserve area. This resulted in the installation of 18 strain gauges. • Luck Stone would contract a third-party vibration monitoring company, agreed to by Loudoun Water, to monitor the strain gauges and provide seismograph reading at appropriate locations along the pipe as mining progresses. All information would be provided to Loudoun Water. • Luck Stone’s blasting will be conducted in a manner that ensures the recommended strains are not exceeded.

Jan 1, 2019