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By WILKES BARRE

AS PREVIOUSLY announced, the semi-centennial meeting of the Institute is to be held at Wilkes-Barre, Pa., on Sept. 12, 13, 14, and 15. An interesting program of technical sessions and excursions is now being prepared by the Local Committee. At the time of going to press the program had not been completed in sufficient detail to permit its being pub¬lished in this number. The detailed program will be published in the September MINING AND METALLURGY, which will be printed in time to be distributed before the Wilkes-Barre Meeting. It may be said in advance, however, that the Com¬mittee has progressed so far in its work that we are assured of one of the -most notable meetings the Insti¬tute has held and that members will miss a rare .treat if they do not attend. The many trips and excursions, as well as the banquet, will be -given to the members as a compliment from the members of the Local Com¬mittee. . . The paper by Howard Eavenson on the Lynch Plant of -the United States Coal and Coke Co. will be illustrated by lantern slides and moving pictures. One of the most appropriate discussions will be that opened by Prof. J. F. Kemp on the Stratigraphy of the Anthracite Region; this also will be amply illustrated.

Jan 1, 1921

By Anthony Iannacchione, Christopher Mark

Residents of Maxwell Hill, a suburb of Beckley, West Virginia, reported from January until March of 1988 a series of earth tremors. The tremors rattled dishes, and the noises associated with tremors were sometimes loud enough to wake people at night. These events were puzzling because Beckley is in an area of low seismic activity. Maxwell Hill is located above abandoned coal mines, though no direct subsidence damage to surface structures has been documented. A research program was initiated to determine whether subsurface ground movements associated with the abandoned mines could be responsible for the seismic activity experienced at the surface. A hypothesis is proposed which states that seismic disturbances can be caused by abandoned mine failure when two conditions are met. First, some instability must exist at the mine level. The most likely cause of instability is the failure of pillars of coal that were left for support at the time of mining. Second, subsurface movements can result in significant seismic activity only when the rock above the mine contains at least one very strong and brittle layer that is prone to fail violently through rupture or fault slip movement. Analysis of the data indicates that both hypothesized conditions for mine-related seismicity appear to have been satisfied in the case of Maxwell Hill. It has therefore been concluded that the earth tremors experienced by Maxwell Hill residents probably are related to the abandoned mines. Analysis of the potential magnitude of these events indicates that they are unlikely to cause significant surface danlage. The probability that future events will disturb the residence of Maxwell Hill should be quite low based on the identified mechanism.

Amongst the unavoidable studies of the mining engineer who desires to reach the maximum efficiency, is the subject of patents. With the fundamental principles of the patent laws of this and other leading countries he should of course befamiliar, but still more should he keep abreast of that practical knowledge which will enable him to act or advise wisely when the patenting of a new invention, or the sale, purchasing, or adoption of a new patented machine or process becomes amatter for consideration. As every engineer worthy of the name is an inventor and more particularly every mining engineer he has a direct interest in watching the progress of legislation and administration concerning patent monopolies.His worldly prospects may indeed, to a considerable extent, depend upon the defeat of bad patent laws and the removal of incompetent officials, or the appointment of better ones. Better patent administration is always in Australia a valid requirement, and until engineers generally take up and press the demand, bad administration is likely to continue. Even though every engineer is not a patentee, nevertheless his interests in patents must always be direct and powerful, and ignorance or apathy in regard thereto must inevitably injure either his own interests or those of his employer. When we consider the tens of thousands of mines scattered through Australia alone, on everyone of which there is expensivepatented machinery, and when we consider the thousands of...

Jan 1, 1901

By J. P. Morris

"INTRODUCTION In the investigation being conducted by the Bureau of Mines concerning the production and utilization of sponge iron, it soon became evident that more information was needed regarding methods for determining the degree of reduction attained in the manufacturing process. Sponge irons made by different processes vary in physical characteristics and chemical composition, and a method of analysis that is suitable for one type is not necessarily applicable to all others. For example, the hydrogen-evolution method, which measures the volume of hydrogen evolved upon treating the sample with acid, accurately determines the oxygen content of some types of sponge iron. However, when the sponge iron contains combined carbon, hydrocarbon gases are also-evolved and large errors may result. Probably no single method will give accurate results in all instances, and for this reason it is desirable to have several reliable procedures available and to know the limitations of each.For measuring the degree of reduction, determination of either metallic iron or oxygen should suffice, although for practical application of sponge iron to the production of steel the oxygen content is more significant. After consideration of proposed methods of analysis in regard to their suitability for routine use and the probable influence of other substances, four procedures were chosen for investigation:(1) Mercuric chloride method.(2) Copper sulfate method.(3) Hydrogen-reduction method.(4) Hydrogen-evolution methods."

Sep 1, 1945

By Micah Nehring, MEHMET KIZIL, Farzad Sotoudeh, Amin Mousavi, PETER KNIGHTS

Production scheduling in underground mines is one of the most important and complex processes in maximising the economic value of an operation over the life of the mine. Due to increasing energy, transportation, processing and smelting costs and reducing water availability, the extraction of ore deposits through underground operations has become more expensive and challenging. A potential productive and efficient solution to mitigate these issues is to integrate pre-concentration systems into the existing mining system to increase ore grades through a preliminary process of rejecting some waste before sending the ore to the energy intensive mineral processing plant. Further benefit of such systems includes the utilisation of the waste and low-grade material in backfilling of open stopes to reduce the transportation costs and surface environmental impact such as reduction of CO2 emissions and waste transportation. The objective of this paper is to present a new mathematical model to optimise the production schedule of underground metalliferous mining operations in the presence of a pre-concentration system. The proposed model optimises the production schedule and sequencing of stopes within a sublevel stoping operation. The results of this study illustrate the potential economic benefits of using a pre-concentration system prior to a mineral processing operation as a result of increased net present value.

Nov 16, 2023

By Robert E. Barieau

A list of 163 references to original experimental PVT data on helium is presented for the period 1895 to 1968. The list is complete as of the start of the Helium Centennial Year, 1968, to the best of the author's knowledge. Citations were keypunched for easy updating and are listed alphabetically by author.

Jan 1, 1968

By Tom Meikle

Long tendon support systems provide several challenges when used in-cycle as part of the secondary or primary support cycle. A two-component pumpable resin, Carbothix, has been in development for use with self-drilling rock bolts, but many of the attributes of this new resin system make it ideal for grouting long tendon support systems. While neat Portland cement grouts or polyester resin capsules have been used with long tendon support systems for many years, two-component pumpable resin systems overcome many of the shortcomings in these systems. The two-component systems dramatically improve the set-time to enable mining face advance with fewer delays, enable longer pumping distances, improve quality control, and enhance load transfer mechanisms. This paper describes the key benefits associated with a new pumpable resin and details the Australian Department of Mines and Petroleum department atmospheric testing results and cable load testing completed by Minova personnel to date. It also details the results of the Australian mine site trials and the introduction of these systems into production use.

Jan 1, 2012

By Mario Terceros H., Bengt H. Fellenius

"ABSTRACTFour strain-gage instrumented bored piles were constructed in a sedimentary, dense to very dense, fine to medium sand in Santa Cruz, Bolivia. Two of the test piles were the normally used bored pile constructed with bentonite slurry and two piles were Bauer Full Displacement Pile (FDP). One of each pair was equipped with the Expander Body, an inflatable steel cylinder that on pressure-grouting provides an enlarged pile toe. Head-down static loading test were performed on three of the piles and a bidirectional test was performed on the fourth pile, a standard pile with Expander Body and a bidirectional cell placed immediately above the EB. The latter pile was tested in 3 phases. First by activating the cell, second, by a head-down test, and, third, by a repeat bidirectional cell test. The static loading tests proved the shaft resistance of the FDP pile to be about twice that of the standard bored pile and that the Expander Body more than doubled the toe stiffness. The strain-gage records showed that the standard bored piles had multiple bulges and neckings, which affected the evaluation of the axial stiffness and load distribution of the piles. The testing programme was used for a prediction event with 60 persons, ahead of the tests, submitting predictions of the load-movement curves for the test piles and also a capacity appraised from the curves.1. INTRODUCTIONOn April 23 - 26, 2013, the First International Conference and Seminar on Deep Foundations was held in Santa Cruz, Bolivia under the auspices of INCOTEC SRL, the UAGRM University, and the Bolivian Association of Civil Engineers and Chamber of Construction. To coincide with the conference, a research study on construction and static and dynamic testing of four instrumented bored piles was undertaken. To ""add spice"" to the conference, a prediction event was organized on the test programme. This paper presents the soil conditions at the site, the type and construction of the test piles, the outcome of the prediction event, and the results of the static tests.2. SOIL CONDITIONSGeotechnical studies comprising SPT and CPT tests with routine laboratory analysis were performed on recovered soil samples. Three SPT boreholes were put down at three of the locations of Pile TP1, TP2, and TP3, at 5.0 m distance from each other. The SPT procedure consisted of manual hoisting of the weight by three crew members pulling on ropes over a pulley supported by a tripod and letting the weight fall by gravity. The groundwater table lies at 3.5 m depth.Figure 1 shows diagrams of the SPT N-indices and the distribution of water content in the three boreholes. The SPT-indices show the soil density to be compact. The average water content is about 15 %, plus-minus a few percent."

Jan 1, 2014

By José Arango

La Planta Hidrometalúrgica de Cerro Verde tiene como objetivo alcanzar la máxima calidad en cada uno de sus procesos operativos. Para ello, desarrolla un diseño que permita la transformación del control remoto a una operación automática, generando decisiones lógicas. En ese sentido, el presente texto señala la importancia de los Sistemas de información de operaciones en el sistema de automatización de Cerro Verde - en tanto es soporte de la implementación de un completo sistema de instrumentación y de la instalación de una red de PLC’s que colectan la información y en base a esta, desarrollan una lógica de operación manteniendo interconectados todos los circuitos operativos. Posteriormente, con el uso de software se crea una interfase de conexión entre la red industrial y la red Administrativa, permitiendo adjuntar la información en una base de datos que junto a la otra base administrativa, constituyen un ERP que da vitalidad a nuestra operación. De forma que los sistemas de informacion instalados en Cerro Verde consideran a los sistemas de instrumentación como los ojos del operador de planta.

Jul 17, 2000

By John Folinsbee, Brian Danyliw, Tony Y. Chong

"Control of fugitive dust has become increasingly important in the mining industry both from a health and safety and environmental standpoint. Mining operations in particular have required improved fugitive dust control due to recent lowering of the allowable airborne silica concentration to which workers can be exposed. Experience has now proven that the implementation of a surfactant based chemical dust suppression system can enhance existing mechanical dust control methods resulting in much more efficient control of fugitive dust.The Porcupine Joint Venture (Dome Mine) utilizes dry secondary crushing and screening that makes it particularly prone to fugitive dust emissions. A variety of potential dust control systems were evaluated and this led to the installation of a surfactant based water spray system to augment the existing mechanical dust collection systems.A great deal was learned through the implementation of this system. This paper describes the entire process, from testing, system design and installation, through optimization and standardization of operation. In addition a variety of problems were identified, and innovative solutions were provided. Also, the metallurgical impacts on down stream processing are highlighted. Finally, a full discussion of overall results including a discussion of the relationship between silica and total dust concentrations is included."

Jan 1, 2005

By I T. Ross

In the last 50 years there have been tremendous improvements in equipment used in development on underground mines. Compressed air powered jacklegs have been replaced by high powered electro-hydraulic drifters on sophisticated drill jumbos and load haul dump units have taken over from small shovels and rail cars.Despite the increase in power applied in key parts of the development cycle, average advance rates have fallen and costs have increased. The factor that is most often regarded as the main contributor to slowing advance rates is increased support requirements. Whilst there is no denying that the drive to improve safety has resulted in the requirement for more bolting and the installation of a skin support (mesh or shotcrete), this is not the only factor.Within the industry as a whole, many of the basic principles of development appear to have been lost over time. This paper looks at a historical case study and discusses some of the features of old development cycles that are no longer in use. This highlights some of the basics that appear to have been forgotten. These may be indicators to what may provide improvements in the conventional drill and blast development cycle.CITATION:Ross, I T, 2014. Development – back to basics, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 67–74 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By Lulie H. Crump

Salient information on reserves, production, and consumption of fuels and energy by State is summarized in this Bureau of Mines publication. Reserve and production data are shown for each of the fossil fuels (coal, crude oil, natural gas liquids, and natural gas) and for uranium. The consumption data of each of the major consuming sectors (household-commercial, industrial, transportation, electric power, and miscellaneous) are broken down by energy source (coal, petroleum, natural gas, hydropower, and nuclear). In addition, total energy consumption in the Nation in 1974 is compared with consumption in 1973 and 1975 (preliminary data).

Jan 1, 1977

By Alfred Petrick

This report analyzes the byproducts systems of lead, zinc, uranium, rare earths, iron, aluminum, titanium, and lithium. Specific byproduct metals covered are cadmium, germanium, indium, and thallium from the zinc system; antimony and bismuth from the lead system; vanadium, radium, and scandium from the uranium system; rare-earth oxides from the rare-earth system; and cobalt, gallium hafnium, and rubidium from other systems. The report discusses various metallurgical systems, marginal and incremental production costs of byproduct subsystems, industry structure and organization, and historical data on price, consumption, and supply.

Jan 1, 1973

Detailed investigation was carried out on the dephosphorization of a number of phosphorus-rich manganese or samples of India by leaching with dilute sulphuric acid. Various process parameters like concentration of acid, liquid-solid ratio, temperature of leaching, time of leaching, and particle size of the ore were studied in detail for the three samples of manganese ore from central India, and optimum values were worked out on a laboratory scale. Preliminary studies show that certain ores which are not easily amemlible to appreciable dephosphorization by leaching with dilute sulphuric acid can be made amenable by :roasting to 700-900°C before leaching.

Jan 1, 1974

By Arnold M. Lansche

[Selenium and tellurium are rare elements in the earth's crust. Their scarcity and primary dependence of supply on copper and lead output are in consonance with the relatively small quantities consumed at 1964 level. Production depending on output of copper and lead creates a supply situation- which would appear to militate against development of large-scale usage of these elements. However, supplies have adequately met. demand in the past decade and can be increased substantially if warranted by new uses for either selenium or tellurium Ores of copper and lead re the principal sources of selenium and tellurium. Byproducts from the smelting and refining of copper and lead concentrates are incorporated in refinery anode slimes from which selenium and tellurium metal are recovered.]

Jan 1, 1967

By Lu Peiyan

A computation model of soil-pile (wall) interaction under lateral loading is presented in this paper. The model has been applied to some engineering projects, and the comparison between computation result and measured result shows good agreement, so the model is proved to be correct and practical.

Jan 1, 1991

By S. S. Gajin

The paper deals with parametric vibrations of an axially loaded pile. The dynamic model is derived by means of Hamilton's principle and reduced to a partial differen­tial equation with variable coefficients and corresponding initial boundary conditions, taking into account the influence of the axial force. By means of Galerkin's method, the partial equation is further reduced to a Matheu-Hill's matrix partial differential equation of the second order. Since the problem of the dynamic stabili­ty has been expressed only for standing piles, the paper analyses in detail two stan­ding piles, one which is restreined, whereas the other is hinged at the toe. In both cases it is assumed that head horisontal displacement is prevented. Using Ruunge-Kutt's method, a computer analysis in the time domain is given for the characteristic parameters and possible boundary conditions. The paper analyses the stationariness of the process, as well as the dependance of the critical excitation frequency upon the pile parameters. The results have been illustrated by respective diagrams.

Jan 1, 1989

By Howard A. Perko

Soldier pile and lagging is a conventional means of temporary excavation shoring. Timber lagging design has traditionally been based upon the designer's experience or empirical rules. One such method is the Goldberg Zoino chart used by the Federal Highway Administration. Most of these methods restrict the designer to a consistent soil profile, certain pile spacing, construction grade timber lagging, and limited depth. The methods do not take into account surcharge loads or a variety of other factors that could arise. A designer working outside of ordinary circumstances with unusual loads, varying soil conditions, or alternate lagging materials has difficulty estimating lateral earth pressures. In rigid earth retention systems, lateral earth pressure is generally assumed to be constant along the length of the wall. In soldier pile and lagging systems, the lagging is often considerably less stiff than the steel soldier piles. As the lagging deflects, the soil tends to bridge between the stiffer elements resulting in a lower pressure on the lagging. Several previously published methods by others for determining this reduced pressure are summarized and discussed. These methods typically consist of using a portion of the active earth pressure in several different pressure distributions. A simple theoretical model is presented for determination of lateral earth pressures on wood lagging. The model is based on a three-dimensional "silo" shaped sliding wedge analysis. Results of the model are compared with other published methods. The model compares well with these methods which cover the normal spectrum of design situations. In addition, the model can be used to estimate lateral earth pressures outside typical situations.

Jan 1, 2008

By S Bourke, R Stone, B Hill

Since Jameson Cell flotation technology was first installed in a coal flotation application in 1988/89 at Newlands Coal Handling and Preparation Plant (CHPP) there have been fundamental improvements to its design which has led to its current status as the leading technology in Australia for fine coal flotation. These improvements, which include key hardware modifications, consist of the re-development of the orifice plate to produce considerable increase in wear life and reduction in power consumption for a given air entrainment and a significant increase in the amount of air that is entrained. Modifications to the downcomer allow maximisation of residence time and air entrainment while changes to the feed and air distribution system allows a reduction in installation cost and a reduction of solids ingress into the air line. Additionally, operational improvements such as the use of recycle to maintain constant flow to the cell feed are discussed. The recent installation at Hail Creek in the Bowen Basin, which consists of three B6000/20 Jameson Cells (6 m diameter bottom-fed distributor with 20 downcomers) will be reviewed as a case study. The latest design and operability of the cells are summarised and compared against one of the original designs at Riverside CHPP also in the Bowen Basin.

Jan 1, 2005

By S. Merjan

Three papers were presented for discussion at the conference: 1) Instrumented driven steel tube piles at Canary Wharf; author: A. R. Gaba, United Kingdom. The author described the Canary Wharf development in the London Docklands, and in particular, the decision to build over the water by driving open-ended steel piles 25m in length into the sands below the soft estuarine deposits. The tubes were then filled with concrete above the sand plug (usually 17m below pile head). Three trial piles were instrumented with: a) resistance strain guages on the inside of the tubes; b) vibrating wire guages on the re­inforcement of the concrete. The trial piles showed elastic behaviour in five cycles of lateral loading, while the verticle load tests showed a definite bi-linear load-settlement behaviour. The initial stiff portion was a result of frictional staff resistance, both inside and outside the tube, with the soil at the base contributing at higher settlements. Loads were taken to three times working load, with no imminent signs of failure.

Jan 1, 1991