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By M. F. Ameur, M. Habak, H. Aouici, M. Kenane

Present study interest by aluminium alloy (Al 7175-T5173) drilled without cooling fluid. The influence of the machining parameters (spindle speed and feed rate) on the holes quality was analyzed. Drilling tools are made of carbide (WC); high speed steel (HSS) and TiN coated carbide (WC-Ti).The Experiment design was reinforced by the application of statistical analysis of variance (ANOVA).The results show that the thrust force is influenced principally by the spindle speed and feed rate. Though, both feed rate and tool materials have statistical significance on the surface roughness. In addition, the objective of correlations between spindle speed and feed rate with the evolution of the machining parameters was established. These correlations were obtained by quadratic regression using the response surface methodology. Finally, useful to select optimum values of drilling parameters, that would minimize thrust force, torque, cutting temperature and surface roughness.

Jan 1, 2015

By C. Debek, A. Wasilewicz, T. Czysz

"Both Polish and European hard coal mining nowadays faces the need of deepening shafts (significantly in some cases) or extending mining hoists, due to the exploitation of deeper coal deposits.In order to protect the crew working within a shaft, rope safety platforms (artificial shaft bottoms) are employed. Old solutions, based on rigid steel constructions with the external damping layers made of e.g. slag and up to several tens of metres long, are intended to absorb the energy of approximately 5 t mass falling a distance of 700 m. However, current requirements often assume a drop of 20 t to a depth of 1000 m or even more.More modern safety platform structures, made of one or more support rings with steel ropes stretched on them (rope platforms), are more compact (up to 3 m high) and lighter than traditional solutions. Multi-ring rope platforms with additional damping layers filling the empty spaces between the ropes are able to absorb sufficient energy to meet the current requirements.Single- and double-ring platforms have been employed in Poland to absorb the energy of approximately 5 t dropping to a depth of 900 m. They have been developed (and some have already been implemented) by SADEX Ltd. and are protected by various patents and patent applications.This paper presents a design for a triple-ring platform structure with six rope nets. FEM analysis was used to model the performance of the platform. According to the simulation, a 20 t mass falling from 1000 m (>100 m/s) will destroy all the nets, breaking most of the ropes and deforming the support steel boards placed on the nets, but will ultimately be stopped by the platform, as its kinetic energy falls to zero."

Jan 1, 2017

By L. C. IlsLey

Permissible blasting units are approved with the understanding that if actively marketed they will be listed as permissible so that all interested in such safety equipment may know what is available. The last detailed list of permissible units was published as Technical Paper 4294/. All of the blasting units of that list have become obsolete or have been modified as covered by extensions of the original approvals.

Jan 1, 1941

By L. C. IlsLey

Permissible blasting units are approved with the understanding that if actively marketed they will be listed as permissible so that all interested in such safety equipment may know what is available. The last detailed lint of permissible units was published as Technical Paper 4294/. All of the blasting units of that list have become obsolete or have boon modified as covered by extensions of the original approvals.

Jan 1, 1941

By F. P. Hassani, A. Hara, M. Momayez

To be competitive on the international market, the Canadian mining industry must reduce its costs, increase its productivity and maintain a high standard of safety. There is a great need today for improved methods that would allow the detection of geological structures in advance of mining to reduce dilution and the monitoring of underground structures to increase safety. This will facilitate planning for optimum exploitation of the mine and to increase production at lower costs. This paper discusses two examples of more efficient mine planning using new technologies such as Ground Probing Radar (GPR). In Kidd Creek mine, GPR technology was used at the 2500and 2600 levels to (1) monitor the stability of the sill pillar; (2) locate the presence of disseminated sulphide pockets in the sill pillar for extracting the mineral content; (3) monitor the stope backs and wall structures to evaluate the effect of on-time filling sequences; and (4)assess rockfill quality in terms of the presence of voids and fractures within the rockfilled areas. In the New Brunswick coal mine in Minto, GPR was used along with core log data to map and construct a 3D block of a section of the bench showing the relative position of different layers overlying the coal seam.

Jan 1, 1996

By M. O. Holowaty, C. M. Squarcy

1750 to 1850: The scene shifts westward across the Alleghenys to the young town of Pittsburgh; charcoal gives way to mineral coal as furnaces grow larger and the blast is heated; above all, Pennsylvania iron is adding strength to the new Nation and building an empire in the West. TWO names are inseparably associated with the Pittsburgh iron industry-those of George Anschutz and John Hayden. The iron ore deposits of southeastern Pennsylvania were found and developed early in the 18th century, and several forges and furnaces were built and operated. It was only after the revolution that the iron men crossed the Susquehanna River, built furnaces in the neighborhood of ore deposits of Franklin County, then along the Juniata River and its valley. Juniata Iron found a ready market in the Pittsburgh area. However, difficulty in transporting it across the Allegheny Mountains induced iron mas¬ters to seek ore and plant locations in the Pittsburgh district. One of the first to reach this area was George Anschutz, who migrated to America in 1789 at the age of 36, reaching Pittsburgh in the fall of 1790. Anschutz immediately set out to organize an iron company in Pittsburgh, and was able to interest some residents in his project. After being informed of an iron ore deposit located only three miles out of town (on the site of the present 26th St. and the Allegheny River) he decided to build there his blast furnace and foundry plant. Total cost of the installation was $300. When the furnace was put in operation, Anschutz, now known as Red George, found that the ore deposit was only an insignificant one and would last no more than a few weeks. A new deposit was found on Roaring Run, in the southeastern corner of Armstrong County. Anschutz transported some of this ore to the mouth of Two Mile Run, where it was loaded on horse wagons and transported to the furnace. In this way, he operated off and on for several months, until the furnace was blown out in 1794. After working for a year as plant manager for John Probst at Langhorntown, he built the Hunting-

Jan 1, 1961

By E. F. Schnitzer, D. R. Haight, G. T. Krogman

The 1997 New Year’s Day Rogue River flood near Medford, Oregon, USA, entered historic channels, eroded a 150-foot-wide buffer, and captured an inactive gravel pond located within the channel migration zone. Channel redirection caused by pit captures threatened adjacent inactive gravel ponds. In response to this capture, a stakeholders group of concerned individuals and organizations was formed. This group ultimately developed a rehabilitation plan, which conformed to the Rogue River’s geomorphic trends. A two-dimensional model, FLO-2D, was used to evaluate channel splits, flood storage, backwater, and future conditions. Modeling results coupled with trend analysis were used to create a stable design where stream barbs, gravel redistribution, a channel outfall spillway, bendway weirs, bank reshaping, and revegetation were integrated into a single plan for a three-mile reach. The quick action by the stakeholders group averted further damage to the Rogue River system and surrounding environment. The project has preserved three miles of mainstem habitat, one mile of side channel habitat, and protected ten gravel ponds from pit capture.

Jan 1, 2006

By I. K. Ozaydin

Analysis of piles groups loaded with large bending moments and both vertical and batter piles can be best performed by matrix analysis. In this paper, a case history about a tall marine control tower is presented. The soil conditions at the site and the results of the computer analysis of the piled foundation are summarized. It is shown that the pile loads are indeed less than the allowable load for a single pile. Pile head loads and moments are used in the analysis of the raft foundation.

Jan 1, 2010

By Y Sha

During the last two decades, China has expanded its iron and steel industry very quickly, from less than 100 Mt/a steel production to over 700 Mt/a. It caused big increases in both domestic iron ore production and imported iron ore quantities year by year. The mode of iron ore supply has changed from almost all domestic supply to major tonnes of imported ore plus domestic ore supply. Over 200 blast furnaces with volumes larger than 1000 m3 each have been built and put into operation. Sinter machines have been enlarged quickly. There are now 135 sinter machines with =200 m2 sintering area each. Pellet production increased from 11.94 Mt in 1999 to 210 Mt in 2011, resulting from rapidly increasing domestic concentrate supply and rapid development of the grate-kiln process. The typical ferrous burden constitution is high basicity sinter plus pellets plus lump. The pellet proportion increased and the sinter proportion decreased gradually. A lot of technical improvements, like deep bed sintering, sintering with a high ratio of limonite, composite sintering, pellet process optimisation, a high ratio of hematite in pelletisation, blast furnace operation with low-grade ferrous burdens and hazardous element control, etc have been made to enhance iron burden quality and to reduce hot metal cost. Chinese iron and steel production is expected to increase slightly in the next few years. Its overcapacity should be controlled effectively. Given the variations of iron ore supply, pellet production will keep progressing in terms of production scale and pellet quality, the sintering process will be improved further by various measures to utilise different ores efficiently, and ferrous burden constitution will be optimised continuously to realise the lowest cost of hot metal production.CITATION:Sha, Y and Wang, Z, 2013. The Chinese iron and steel industry response to the challenges of iron ore supply, in Proceedings Iron Ore 2013 , pp 7-14 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Chris Larsen, Carole Fortin, Dave Scott, Curtis Deredin, Ian Orford, Jean Guy Gauthier, Andy Trusiak, Lyne Côté, Mike Cooper

"Upon successful commissioning of the Stage Grinding Project (Cormier et. al., 2002), process improvements predicted through pilot plant testing were obtained in several flotation circuits, resulting in higher grades and recoveries for zinc and lead concentrates. Subsequent to establishing new baseline operating conditions from the Stage Grind Project implementation, additional opportunities were identified, and through the application of Six Sigma methodologies further gains were made. Six Sigma improvement projects were carried out in the copper-lead, zinc, lead upgrading and bulk flotation circuits. The overall performance increase resulting from incremental improvement projects has been substantial.Most remarkably, given the operational maturity up to the late 1980’s, the Brunswick concentrator team has continued to deliver a steady stream of major improvements over the past fifteen years. While senior managers and their programs have changed several times, there have been some critical constants over the long run. Common elements have been a commitment to team work, a commitment to recruit and maintain technical personnel, a structured business improvement framework supported organizationally by senior management, and focus on a few priority initiatives rather than trying to fix everything at once.The paper briefly discusses the longer term setting and then endeavors to illustrate, with examples, how improvements are presently achieved by applying the Six Sigma quality program.INTRODUCTIONThe Noranda Inc. Brunswick Mine, located near Bathurst, New Brunswick, is one of the world’s larger lead/zinc mines. Milling of ore began in 1964 from the No. 12 orebody, with an expansion in 1966 to accommodate ore from the No. 6 mine. In excess of 100 million tonnes have been milled to date. The concentrator employs differential flotation to produce lead, zinc, copper, and lead/zinc bulk concentrates. The ore is massive sulphide, with approximately 20% valuable minerals, 60% pyrite and 20% silicates."

Jan 1, 2005

By T. N. Rushton

Rate minima are encountered in the reduction of magnetite with hydrogen. In a certain temperature zone, the reaction rate decreases with rise in temperature. This is inexplicable by classical kinetic theories; neither is a transition in reduction mechanism suitable for interpreting the observed behavior, This anomaly can be fully explained by hypothesizing two species of chemisorbed hydrogen with different adsorption coefficients and activation energies for adsorption. Competition between two energetic states of adsorption occurs with temperature rise, with the low energy state predominating below the anomalous temperature zone and the high energy state above it. The presence of two possible adsorption sites appears to be characteristic for oxidic adsorbents.

Jan 1, 1968

By H Q. Zhang, M C Chai, W Fu, H Y Chen, L M. Wei, Q J. Yang

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Fozichong deposit – located in the south-western segment of the giant Qinhang metallogenic belt, South China – is a large-sized lead-zinc polymetallic deposit. This deposit contains two main ore districts, termed as the Guyi ore district in the north and the Hesan ore district in the south respectively. We present an integrated data set on sulfide minerals, fluid inclusions and stable isotope (H-O-S-Pb) geochemistry to better understand the features and genesis of the Fozichong deposit.Field and paragenetic relationships indicate three mineralisation stages forming the early (Po+Sp+Gn+Ccp+Py+Di+Ep+Qtz), middle (Sp+Gn+Ccp+Py+Ep+Chl+Qtz) and late (Gn+Sp+Py+Qtz+Cal) sulfide assemblages respectively. Mineral chemistry – particularly S/Fe and Co/Ni ratios in pyrite, Zn/Fe, Zn/Mn and Zn/Cd ratios in sphalerite and Pb/Ag ratios in galena – indicates a magmatic association for the sulfide minerals.Quartz and calcite coexisting with the sulfide minerals of various stages host abundant fluid inclusions. Quartz in the early stage contains two- or three-phase CO2-H2O and liquid-rich aqueous inclusions, which have homogenisation temperatures of 162~365°C and salinities of 2.9~17.8 wt per cent NaClequiv, whereas quartz and calcite from the middle and late stages are dominated by two-phase, liquid-rich aqueous inclusions that have slightly lower homogenisation temperatures (153°C~320°C) and much lower salinities (1.0~6.0 wt per cent NaClequiv). Hydrogen isotopes (dD = -59‰~-41‰), analysed using fluid inclusion waters from quartz and calculated oxygen isotopes (d18OH2O = -5.47‰~4.00‰) for the equilibrated ore fluids, indicate that the ore-forming fluids may have been sourced from magma and mixed with groundwater in the late stages. Sulfide minerals have d34S values of 2.3‰~4.3‰, consistent with a magmatic-derived source for sulfur. Lead isotopes (206Pb/204Pb = 18.592~18.794, 207Pb/204Pb = 15.648~15.864, 208Pb/204Pb = 38.909~39.580) confirm that lead and, by inference, zinc were mainly derived from magmatic rocks, with subordinate contributions from sedimentary rocks.Various lines of evidence support that the formation of the Fozichong deposit has close genetic association with the granite porphyry intruded in the late Yanshanian period (106 Ma), and it can be classified as a magmatic hydrothermal type lead-zinc deposit. We propose that the Hesan and Guyi ore districts may represent the proximal and distal products of a magmatic – hydrothermal system respectively.CITATION:Fu, W, Zhang, H Q, Chai, M C, Yang, Q J, Chen, H Y and Wei, L M, 2015. Genesis of the large-sized Fozichong lead-zinc polymetallic deposit, Guangxi, south China – constraints from the sulfide mineralogy, fluid inclusions and isotope geochemistry , in Proceedings PACRIM 2015 Congress, pp 609–614 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

S. R. Carter (Mount Isa Mines Ltd., Mt. Isa): I found many ideas to interest me in Haddon King's paper "Notes on Ore Occurrences in Highly Metamorphosed Precambrian Rocks" (Stillwell Anniversary Volume).At Mount Isa I have not been happy about some of the longstanding appreciations of the geological evidence as fresh data accumulated, and as more and more knowledge has been building up outside Mount Isa in recent years of sedimentary deposition of sulphides.Accordingly, I organized a small section of the Geological Department at Mount Isa at the beginning of 1958 under Senior Geologist, W. J. Murray to reappraise our geological record and investigate old interpretations and new ones that arise. The work is expected to take several years to complete, but it is hoped that sufficient will be done before then to permit the most plausible story on the ore genesis to be chosen. In the meantime, W. J. Murray has proposed, in a Company Report, that the.epigenetic features of the silver,lead-zinc deposits, which are essentially conformable with the shales, could have resulted from remobilized syngenetic deposits.Haddon King, on p. 159; has listed six assumptions that are required by a magmatic-hydrothermal theory of, origin for conformable deposits. It is interesting to consider the Mount Isa silver-lead-zinc deposits in terms of these requirements.My comments are listed in the same order as Haddon King's assumptions:(a) "The source of the constituents is magmatic and they have become available in successive waves of zinc-rich, lead rich, manganese rich, silver rich, etc, instalments in accord...

Jan 1, 1959

A series of petrological studies were carried out on the characteristics of alteration and mineralisation in mainly structural-controlled (Deep Star, Meikle, Deep Post) and predominantly lithological-controlled (Post-Betze-Screamer and West Leeville) gold deposits in the northern district of the Carlin trend, Nevada. Alteration and mineralisation in these deposits are hosted in a sequence of calcareous clastic units of the Devonian Popovich Formation, into which have been emplaced a number of Jurassic intrusions, and syn- to post-mineral Eocene dikes. Four hydrothermal events have been recognised in these deposits: an initial Devonian base metal system and early diagenesis; a Mississippian stage of alteration in conjunction with burial metamorphism; contact and hydrothermal alteration and base metal-gold mineralisation associated with the emplacement of the Jurassic intrusions; and a Carlin-style gold system related to Eocene magmatism.

Jan 1, 2004

By M. A. Reyes

This experiment investigated the effects of different machine mounted area lighting technologies on visual performance. The primary objective was to conduct a comparative evaluation of the lighting technologies based on the visual performance of thirty-six human subjects in a simulated underground mine environment. Incandescent (Incand), fluorescent (Fluor), and light-emitting diode (LED) technologies were used to create four lighting combinations. Visual performance was quantified for the detection of movement in the peripheral field of view and the identification of ground hazards. Measurements were made of the speed [response time measured in milliseconds (ms)], the accuracy (the number of targets and objects missed), and the subjective discomfort rating of the glare experienced for each lighting combination. A secondary objective explored the effects of aging on visual performance. The results indicate that lighting combinations which consisted of LED area lights significantly improved visual performance for the detection of hazards found in the peripheral field of view, as well as those found on the ground. They furthermore, indicate that age plays a significant role in visual performance.

Jan 1, 2009

By Qinmeng Wang

The oxygen bottom blown copper smelting process is a new technology which has been widely applied to the copper production in China. In this work, a computational thermodynamics model for this technology has been established, based on smelting mechanism and theory of Gibbs free energy minimization. The calculated results from the model agree well with the actual industrial data, indicating that the model can be used for the predictions under different operating conditions. The tendencies of the key parameters (such as Cu losses and Fe3O4 content in slag) and the distribution ratios of the minor elements (such as Pb, Zn, As, Sb and Bi) can be predicted by adjusting the oxygen/ore ratio charged into the bottom blown copper smelting furnace. The model can be used to monitor and optimize the industrial operations of the oxygen bottom blown copper smelting process.

By Frederick T. Fischer

The New Jersey Zinc Company began a program of exploration in Middle Tennessee in 1964. The target horizon of the exploration project has been the Knox Dolomite which is a low-yield aquifer over nearly the entire Central Basin of Tennessee (1). With the exception of a few hundred acres in the Wells Creek and Flynn Creek disturbances (astroblemes?), the Knox Dolomite in Middle Tennessee is known only in subsurface. In January of 1969, New Jersey Zinc announced the discovery of a major zinc deposit near Elmwood, southeast of Carthage. This is on the northeastern flank of the Nashville Dome where the nearly flat-lying beds have an average eastward slope of about 50 feet per mile. The anticipated development of a mining situation has emphasized the significance of hydrologic relationships in the region as a whole and especially in the Elmwood area. These relationships affect several areas of concern which ma be generally grouped into two broad classes; i. e. , (1) Problems of a Public Nature - involving the prevention of the contamination of potable aquifers, the prevention of the contamination of surface waters, the prevention of the capture of presently utilized water, etc.; and (2) Problems of Mining Economics - involving pumping capacity and costs, the possible need for equipment of special composition, underground environmental conditions, etc. Exploration drilling in Middle Tennessee has contributed additional information about the Knox aquifer and

Jan 1, 1970

By R. E. Heithecker

In June 1933 the Bureau of Mines, in cooperation with the State of Oklahoma and the Oklahoma City Chamber of Commerce, published a report of the gas at reserves in the Oklahoma City oil field3/ based upon data as of October 1932, at which time there were 43 classified gas wells in the field, The estimates were obtained by the ?porosity-area" method. There are two general methods of estimating natural-gas reserves. The porosity-area method, as used by Hill and Rawlins, is used when a gas field is comparatively new but after enough drilling has been done to determine the average thickness, porosity, and areal extent of the producing horizon. The "pressure-volume? method of estimating gas reserves, the method used in this report, nay be used after a sufficient volume of gas has bean withdrawn from the reservoir to cause an appreciable decline in reservoir pressure.

Jan 1, 1937

By J. E. Nesset

"Significant progress has been made over the past few years on characterizing and understanding the hydrodynamic properties of frothers and collectors and their effect on flotation performance. This new understanding of the relationship between chemistry and hydrodynamics has dramatic implications for how flotation circuits should be controlled and optimized. Previous work has shown that choosing a frother of the right ‘strength’ is critical to the optimization process, and the work and discussion presented here serve to strengthen the argument. In addition, we know that collector chemistry will also influence hydrodynamic properties and needs to be taken into consideration. To achieve the desired outcome, the overall system of reagents and operating parameters must be considered. This paper describes and discusses some of the findings from recent research on frother and collector chemistry effects (on hydrodynamics), and how this knowledge can be used to improve flotation performance. Examples from plant experience are discussed.INTRODUCTIONFrothers perform various functions in flotation but the primary ones are control of bubble size in the pulp zone and stabilization of the froth zone. Laskowski (2003) was among the first to try to capture both roles in characterizing frothers in order to provide a basis for frother selection for a given duty, as well as to explore the link between function and frother chemistry (structure). The method he used requires bubble size data and a frothing index; the procedure has been simplified by Cappuccitti and Finch (2008) using gas hold-up to substitute for bubble size, and froth height (without overflow) as the froth stability metric. The gas hold-up/froth height relationship will be referred to as ‘hydrodynamic characterization’. Essentially, the gas hold-up parameter reflects the sum of the hydrodynamic conditions in the pulp phase (water in this case), i.e. the effect of bubble size plus the apparent impact of the water surrounding the bubble due to the frother (Finch, Nesset and Acuna, 2008). Similarly, the stable froth height parameter reflects the sum of hydrodynamic conditions in the froth, i.e. the effect of bubble size undergoing coalescence plus the influence of the water in the lamellae and Plateau borders between bubbles. It could be argued that the gas hold-up/froth height relationship is a superior one to simple bubble size/froth index for discerning differences in frother behaviour"

Jan 1, 2010

The only economically significant deposit of dolomite in New Zealand is at Mount Burnett, in north-west Nelson. The dolomite, associated with marbles and schists, is complexly deformed, and is of Paleozoic age.A very large quantity is present, although the recoverable amount is to some extent limited by the difficult terrain.Physically the quality of the dolomite is excellent. It is a tough, durable, fine grained rock. Chemically it is a little more variable. The range and frequency o~ the more important impurities are illustrated by hlstograms, as is the "dolomite factor"-a measure of the amount of the mineral dolomite in the rock. lbe dolomite factor averages 84 per cent, the remainder of the rock consisting largely of calcite. Quarrying, milling, production, and uses are described. In 1966 production reached 13,250 tons.

Jan 1, 1969