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By F. T. Mooney

Introduction The Flin Flon mine of the Hudson Bay Mining and Smelting Company, Limited, is on the interprovincial boundary between Manitoba and Saskatchewan, about four hundred miles north of the Canada-United States boundary. The orebodies are gold, silver, zinc, and copper replacement deposits occurring as irregular lenses of massive sulphides, arranged en echelon, and irregular masses of disseminated copper sulphides in chlorite. The country rocks are of Precambrian age, dominantly lava flows. Development of the Mine The mine is opened by two vertical main shafts- the North Main and South Main shafts- 3,800 feet apart. The North Main shaft has a depth of 2,210 feet and the South Main shaft is completed for stoping operations to the 3,250-foot level (see Figure 1). These shafts are connected by main haulages driven, on the footwall side of the orebodies, at 520-foot intervals down to the 2,210-foot level. No. 3 (subsidiary) shaft is on the footwall side of the orebodies at a point between the North Main and South Main shafts, 2,400 feet south of the former. It has a depth of 3,250 feet and connects with all main haulage levels- with both Main shafts down to the 2,210-foot level and with the South Main shaft on the 2,750-, 3,000-, and 3,250-foot levels. Other openings tO the mine include B North fan raise, the opening due to the recovery of the open pit sill pillar, and several back-fill raises.

Jan 1, 1949

By D. Bouchard, M. Forté, A. Charette

A transparent replica of a casting die was built to achieve a better understanding of the filling mechanisms of aluminum in high pressure die casting. Water and tomato paste were respectively used as analogues for the Newtonian liquid aluminum and the non-Newtonian semi-solid aluminum. The transparent die was installed on an industrial casting press and filling was filmed with a high-speed camera. Differences between the Newtonian and non-Newtonian fluids are presented and discussed.

Jan 1, 2006

By D. K. Deardorff

The hafnium-vanadium phase diagram was constructed within an estimated accuracy of ± 10° C and ± 2 wt pct composition. Alloys for investigation were melted under an atmosphere of purified helium by nonconsumable tungsten-electrode arc melting on a water-cooled copper hearth. Melting points were determined by optical pyrometer, and the remaining phase relationships were investigated by metallography, thermal analysis, and X-ray diffraction. The existence of a face-centered cubic intermetallic compound HfV2 (a = 7.38 A) was confirmed. A eutectic reaction occurred at 20 wt pct vanadium and 1,395° C to yield HfV2 and 8 solid solution. HfV2 melted incongruently by a peritectic reaction at 1,480° C, and the 3 solid solution decomposed eutectoidally at 1,165° C and 6 wt pct vanadium to yield HfV2 and a solid solution. The eutectoid, the eutectic, and the peritectic isotherms extended from 1 to 36.3 wt pct vanadium, from 8 to 36.3 wt pct vanadium, and from 26 to 89.5 wt pct vanadium, respectively. Terminal solid solubilities of hafnium in vanadium at 1,300° C and of vanadium in hafnium at 1,100° C determined to be about 3 and 1 wt pct, respectively.

Jan 1, 1965

By Edward J. Harvey

Joplin, one of the most famous zinc mining camps of a bygone era, is today experiencing a healthy growth in manufacturing enterprises. Manufacturing requires water, and knowledge of its availability and quality often is the main factor in location of industry. For this reason in January 1964, on the suggestion of the former State Geologist, Dr. Thomas R. Beveridge, a study of the water resources of the Joplin District was undertaken as a cooperative effort of the Missouri Geological Survey and Water Resources now under the direction of Dr. William C. Hayes and the U. S. Geological Survey. The project area is in southwestern Missouri on the Springfield Plateau and is bordered on the west and north by the Osage Plains of Kansas and Western Missouri, (fig. l). Upland altitudes rise from 900 feet above sea level in the west to 1400 feet in the east. The countryside is rolling to moderately hilly and much is excellent farmland.

Jan 1, 1965

By J. J. Barakso, C. Tarnocai

This paper outlines a method of testing for the mercury content of rocks, soils and plants. Techniques of sample collecting are described and the analytical procedures outlined. Examples are given of mercury determinations in two known mineralized areas in British Columbia - Copper Mountain Mines and Pacific Nickel Mines.

Jan 1, 1970

By L Rachmad

Freeport IndonesiaÆs Deep Ore Zone (DOZ) mine is the new underground block caving mine within the East Ertsberg Skarn System (EESS) deposit which started production in mid-2000. The DOZ will produce 25 000 tpd using mechanised block cave mining method and will be the fourth underground mine opened within the EESS deposit. Evaluations were made on former block caving mines at PT Freeport Indonesia (IOZ, GBT Area I and II) in order to design a more appropriate support system. As a permanent support, the thread bar bolt support system is widely used in the DOZ mine. The advantages of this system are ease of operation, quality control and high bond strength. The main problem of this system is the curing time of about 28 days to achieve maximum strength, necessitating the installation of a temporary support for its implementation. In this instance, the system was inefficient in operation and studies were required to find an alternative grouting system. This paper examines the evaluation of thread bar bolt support system and compares the performance of two types of grouting (resin cartridge and cement cartridge) with cement grouting performance. The evaluation is conducted with a pull out test. The advantages and disadvantages for each grouting method, comparison of cost estimation and grouting application in mine scale are presented in this paper.

Jan 1, 2002

By L. C. Karrick

The Bureau of Nines has received many inquiries on the subject of assaying oil-shales, both from individuals who desire to wake their own assay while in the field, and also from Commercial assayers and investigators. The present paper describes the assay retort used by the Bureau of Mines. in the research work on oil-shales now in progress at the Intermountain Experiment Station of the Bureau at Salt Lake City, Utah, and at the Colorado cooperative oil-shale laboratory, Boulder, Colorado. This retort, which was developed through experimentation in the bureau's laboratories, has been found to be convenient in use and. capable of yielding reproducible results. M. J. Gavin, Oil-Shale Technologist, gave valuable assistance in preparing the subject matter for publication and made many helpful suggestions during the experiments made by the writer in the course of the development of the assay retort. L. A. Anderson, research "fellow" University of Utah, assisted in the preliminary development of the assay retort.

Jan 1, 1921

By Ralph L. Merklin

One of the most commonly employed set of calculations in mill design and research is the material balance, known in wet beneficiation plants, as an Ore and Water Balance. For mill designers, the balance is one of the principal requirements in determining the proper size of launders, pipelines, process equipment, etc. In process development, one of the major goals is the establishment of an optimum balance. The usual procedure for calculating a material balance involves a manual technique utilizing reference tables, pre -obtained data, and a slide rule or desk calculator. With these, the engineer must perform a series of calculations which are repetitious in nature and time consuming. Figure I is the flowsheet of the grinding and flotation circuits for a copper concentrator. The initial ore and water balance was calculated manually and required approximately 24 manhours. Later, a number of changes were made in the balance, each of which required an average of 8 manhours.

Jan 1, 1967

By Y. Luo

Although considerable progress has been made in the last decade in predicting surface subsidence over longwall panels, a number of important issues deserve further studies in order to improve the techniques and accuracy of subsidence predictions. Some of the problems are: (1) subsidence over the chain pillars between mined longwall panels; (2) subsidence development process after face stop due to either a vacation or the completion of a longwall panel; and (3) subsidence initiation and development process over the setup entry area in the initial stage of mining a longwall panel. In this paper, the measured data related to the targeted problems are presented, the data analysis techniques are briefly introduced, and some of the prediction methods developed based on the collected data are proposed. The proposed methods can be used as supplemental tools for the existing subsidence prediction models to improve their prediction accuracy.

Jan 1, 1991

By S. Alpay

Underground mining method selection (UMMS) is one of the most important decisions that mining engineers have to make. Choosing a suitable underground mining method to extract a mineral deposit is very important in terms of economics, safety and productivity of mining operations. In real life, UMMS is one of the Multiple Attribute Decision Making (MADM) problems and decision makers have always some difficulties in making the right decision in the multiple criteria environment. Analytic Hierarchy Process (AHP) and Fuzzy MADM (FMADM) are the MADM tools and can be used for the selection of the best underground mining method by considering the problem criteria. UMMSMADM is a computer program which is based on AHP and FMADM and it can analyze the UMMS problems and produce the best underground mining method considering different deposit shapes and ore bodies.

Jan 1, 2010

To produce high quality castings, one must monitor the melt quality by evaluating such parameters as the grain refinement and silicon inoculation and modification during the production of the commercial casting. Thermal analysis is a tool one can use for both monitoring and providing input to the process control of the operation. The current technique of performing thermal analysis in commercial foundries is to pour a relatively small quantity of the molten aluminum alloy into a sampling cup and to then acquire the cooling curve. This approach is somewhat simplistic in that one has limited control of the cooling rate and hence the solidification rate of the sample. Moreover, this process requires a fair amount of user intervention and effort. In the past, studies have been conducted in an attempt to develop a system for conducting thermal analysis in-situ. In a study at McGill University, an alkali based heat pipe system was developed for conducting thermal analysis in-situ. While the concept was deemed as very desirable, the complexity of the equipment and procedure was a substantial negative component. In order to improve the technique of accomplishing real-time thermal analysis with an in-situ probe, a new method that is based on McGill heat pipe technology was developed. In the new system, a controllable and flexible water based heat pipe probe is used to solidify a small quantity of metal while residing in the melt. The solidified aluminum is remelted after completing the thermal analysis. This is a key feature of the probe. It resides permanently in the melt yet it is able to both solidify a sample of the melt and then to subsequently remelt it. Various solidification rates encountered in commercial castings are attainable by adjusting the heat extraction rate of the unit.

Jan 1, 2004

By L. Dufourm

This paper presents a review of plant layout considerations incorporated into recent designs of SAG/Ball mill circuits for two medium sized concentrators. The plant layouts presented and the design concepts discussed, relate to smaller SAG circuits, but can equally apply to larger milling circuits. Included are design concepts and ideas introduced by the various project teams, and the focus is on the primary factors of any layout design which are safety, constructability, operability, and capital cost.

Jan 1, 2012

By Alex Meystel, Diran Apelian

"In this paper, an outline is given for a theory of intelligent control (IC) of manufacturing processes (MP) based upon what all of them have in common: all MP's can be represented as distributed networks of sequential/parallel elementary ""lumped"" models; all elementary models are organized by definite input-output conditions, and by the set of constraints; all elementary models incorporate not only well defined physical knowledge, but also assumed physical knowledge, expert knowledge, expected knowledge to be obtained during the process from sensors, etc. This creates a hierarchy of elementary controllers coordinated by local coordinators of different levels up to a global coordinator. The latter verifies the adequacy of MP by using a holistic image of the process: depictogram. The structure of knowledge based controller is introduced, and the analytical/linguistic tools of control are presented. The concept entails a number of perspectives which are discussed in the conclusions.1. IntroductionIt is becoming increasingly clear to those of us in Engineering and Technology oriented fields that the so called ""service industries"" do not create wealth. Moreover, it is now accepted that manufacturing is the key to the creation of wealth from a socio-economic point of view. This appreciation of the importance of manufacturing is reflected by the transformations we are seeing in our factories, as well as the changes in both curricula and research activities of our universities. Though we find these changes to be in the right direction, there is yet much more to be done to advance the frontiers of manufacturing and materials processing as we approach the third rnillenium."

Jan 1, 1988

By C. R. Tinsley

Investment activity in the Pacific Rim of Fire has seen a phenomenal surge from epithermal gold exploration. Individual countries are attractive because of lower up-front minerals lease costs (US, Canada), better geological prospectivity (Chile, Indonesia), or cheaper equities (Australia). Since the October 1987 stock-market crash, large companies are shedding minority joint venture interests to focus on core businesses. Some vertical integration is evident in Japanese coal investments in the Pacific Rim. This paper does not cover the aluminum industry oligopoly which is multi-national in character nor does it cover the many Canada to US minerals investments. It will be interesting to see if the new US-Canadian free-trade treaty will reverse that investment flow.

Jan 1, 1990

By J Meinhart, J Rodler, I Katolicky

The ever increasing number of vehicles is leading to slow-moving and even stationary traffic sitting longer in traffic jams over extensive city areas. This traffic situation causes a sharp increase in pollutant emissions from vehicles, and high levels of pollution usually result throughout the built-up area. Reducing the pollution level by using traffic routing measures to speed up the flow of traffic in the existing street network is only possible in exceptional cases.In many cases the only option for achieving a significant improvement in traffic conditions is to shift the traffic underground using a road tunnel or underpass. Such tunnel routes suck off the traffic from large sections of the city, thereby easing the overall traffic flow. Thus on the one hand it produces a sharp reduction in pollution levels in the area of the tunnel route, but on the other hand it can result in locally increased exhaust pollution levels from longer tunnel systems that require mechanical ventilation. The air extracted by the ventilation system is blown out into the atmosphere either directly through the tunnel portal, or via a venting tower. Pollution can therefore occur in the area surrounding such exhaust air outlets.Thus if a tunnel is planned in a city, then closer investigation is required of both aspects: the reduction in pollution in the area of the tunnel route thanks to relocating the traffic and easing congestion, and the increased short-range pollution around the tunnel portals (shafts).

Jan 1, 1999

By Hiroyuki Sano, Hiroshi Chida, Katsuya Toda, Takafumi Sasaki

Saganoseki Smelter & Refinery is one of the largest copper producers in Japan to produce 450,000 tons of new copper annually. Saganoseki used to operate six PS converters with "4 Hot-2 Blow" scheme, but managed to change its operation to "3 Hot-2 Blow" scheme with four PS converters, while maintaining the same production capacity. To achieve the operational change, the following improvements have been carried out; 1) Extending service life from 220 to 350 batches, 2) Shortening cycle time by increasing the blowing rate and the matte grade, 3) Reducing environmental impact by applying sophisticated fugitive gas collection system and 4) Saving energy by waste heat boiler’s modifications. The operational change has been successfully executed, and results in drastic productivity increase and cost reduction. Currently, Saganoseki is maintaining the efficient and consistent operation with 4 PS converters. This paper describes the above-mentioned improvements for increasing productivity and the recent operational conditions of the PS converters.

Jan 1, 2015

By E. Gaucher, D. C. Gagnon

"The paper refers to methods and concepts used in the computer treatment of banks of geophysical, geochemical and geological data, relating to the exploration of massive sulphides. In particular, a data bank of 400 drill holes on independent conductors can be used to calculate probability levels of intersecting a certain quantity of sulphides according to the characteristics of the conductor. Inversely one can, using the data bank and some cost assumptions, simulate and optimize the cost of intersecting a certain quantity of sulphides by selecting drill targets among conductors according to conductivity, magnetism or gravity. Problems of noise, inherent in any simulation, are illustrated in this paper by the results of a study of the nomenclature of volcanic rocks of 27 drill holes by forty geologists. Compilations of data banks are long and timeconsuming, and it would help to standardize to allow exchange of data. We believe that such efforts may result in the discovery of more mineral deposits and at a lower cost. The present study is supported jointly by SOQUEM The New Jersey Zinc Co. and Cominco Ltd."

Jan 1, 1973

By Harold L. Gibbs

The purpose of this paper is to encourage petrographers to prepare thin sections, as the demand for microscopic examination of rocks, ores, and metallurgical products is becoming more general in .the mining metallurgical-fields. This paper has been written with the knowledge that the successful thin-section methods and the several new techniques herein described will be helpful to all engaged in this field of work. Detailed instructions for making thin sections by methods developed at the Salt Lake-City laboratory of the Bureau of' Mines are given in this paper. Several new techniques are described for making thin sections of loose grains and fine sands and for making good thin sections of highly altered and friable rocks. The methods described insure superior bonding of the rock to the glass slide, thus virtually eliminating any failures due to parting of the section from the glass slide, and permit fast mounting, grinding, and finishing, thereby materially lessening the time required to prepare thin sections.

Jan 1, 1950

By Wael Abdellah

Mine haulage drifts are the primary access to the mining blocks of an orebody in a multilevel mining system of a tabular ore deposit. The stability and functionality of haulage drifts are thus crucial to the success of a mining operation. Drift instability could lead to serious consequences such as injuries, production delays and higher operational cost. In this paper, the performance of the haulage drift stability is evaluated on the basis of the primary rock support system comprising 1.8 m resin grouted rebars in the drift walls and 2.1 m long bolt in the back. Two failure criteria namely the extent of Mohr-Coulomb yield zones around the drift, and linear elastic brittle shear failure are adopted and compared, with respect to lower level and same-level mining and filling sequence in the vicinity of the haulage drift. The case study is one of the #1 Shear East zone of the Garson Mine in Sudbury, Ontario. Random Monte Carlo (RMC) technique, which has been previously established to assess the haulage drift stability, is employed in this investigation. The RMC technique is used in conjunction with finite difference modelling software FLAC for random assignment of model input parameters in the FLAC grid. Deterministic model results reveal the drift behaviour in terms of deformation (convergence) and mining-induced stress distribution. Comparison between the two different criteria is carried out to determine which method is most suitable in evaluating unsatisfactory drift performance. The results are presented in terms of probability of instability and categorized with respect to failure condition and mining step. It is shown that the brittle shear failure condition based on linear elastic response calls for enhanced support system at a later mining step than what Mohr- Coulomb yielding condition does. The paper presents a detailed discussion of the stochastic analysis results.

Jun 1, 2012

By J. Gathje

Normal process development for pressure preoxidation treatment of refractory gold ores starts with laboratory batch autoclave tests, followed by operation of a continuous autoclave pilot plant for confirmation of the various process options. This scheme will generally provide good information showing the effects of such variables as grind size, time, and temperature, and will indicate whether autoclave preoxidation will produce solids that are amenable to cyanidation for gold recovery. However, several recent test programs conducted over the last three to four years have shown that the cyanide leaching responses of treated solids from the batch tests can differ considerably from those achieved by the continuous pilot plant autoclave. Examples are provided to demonstrate these differences and to show the importance of extending the laboratory investigations to include the use of a semicontinuous autoclave test procedure. A test case is cited in which this procedure provided data that could not be obtained from batch tests.

Jan 1, 1995