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By Doug Harding

The Niagara Tunnel Project (NTP) is a 10.4-km- (6.5- mile-) long, 14.4-m (47.5-ft) bored tunnel that will run under the city of Niagara Falls from the Upper Niagara River to the Sir Adam Beck power station. The completed project will enhance the capacity of the Sir Adam Beck power station by adding 500 m3 /sec (17,657 cu ft/sec) of water through the tunnel. The project uses the world?s largest hard-rock tunnel boring machine (TBM) at 14.4 m (47.5 ft) in diameter to excavate the tunnel. Features of the project include the use of a high performance (HP) main beam TBM, state-of-the-art ground support and tunnel logistics systems. A continuous conveyor is used for muck transport from the TBM to the disposal area In June 2004, the Ontario government announced that Ontario Power Generation (OPG) had been given approval to proceed with the third tunnel under the city of Niagara Falls ? the first two tunnels were constructed in the 1950s using drill-and-blast techniques. The third tunnel, appropriately named the Niagara Tunnel Project (NTP), consists of a 10.4-km- (6.5-mile-) long TBM-bored, concrete-lined tunnel with a finished diameter of 12.5 m (41.1 ft). In August 2005, OPG the selected of Strabag of Austria, one of the largest construction companies in Europe, as the contractor to build the NTP at a price of C$600 million. In September 2005, Strabag selected The Robbins Co. of Solon, OH to design, manufacture and deliver a new 14.4- m- (47.5-ft-) diameter high performance, state-of-the-art main beam hard rock TBM to be used in the excavation of the tunnel. To meet the aggressive construction schedule as requested by OPG/Strabag, the TBM needed to be sup-plied as ready-to-bore within a 12-month period after the contract was awarded to Robbins.

Jan 1, 2008

By G. Bulut

The recovery of copper and cobalt from ancient copper slags from the Küre region of Turkey was investigated. A fayalitic-type of ancient copper slag containing 1.24% Cu, 0.53% Co and 53.16% Fe were subjected to an experimental study. Two different routes were followed to recover the metal values. The first route was roasting the slag with pyrite followed by leaching. The second route was flotation of the slags, roasting of the flotation tailings with pyrite and leaching. The second route was found to be suitable for the treatment of the copper slag studied. In the flotation step, a copper concentrate containing approximately 11% Cu was produced with a 77% recovery while 93% of the cobalt stayed in the tailings. In the roasting experiments, the effects of roasting time, pyrite: slag ratio and roasting temperature on the dissolution efficiencies of Cu and Co were investigated, and the optimum conditions were determined. In the tests, 87% of the cobalt dissolution was observed after one hour of roasting at 500°C with a pyrite: slag ratio of 3:1. The copper dissolution in the tests was 31%. Based on the results of this study, a process flowsheet is proposed for the evaluation of these slags.

Jan 1, 2007

By J. Galloway, P. K. Hofmeyr

Obviously all mining operations require much analytical work to be carried out. This starts with exploration, becomes more stringent with the evaluation of a mineralised area and finally becomes on-going when mining operations are under way. All these phases are carried out by geologists, metallurgists and mining engineers. They require analyses to carry out their functions but usually have no involvement in the analyses themselves. Analyses are carried out at commercial laboratories or in-house analytical laboratories. In the past in South Africa the tendency was for the larger mining houses to have their own centralised laboratories for exploration samples with each mine having it?s own laboratory to meet only that mine?s requirements. The centralised laboratory maintains QC functions at the subsidiary laboratories. In other mining areas of the world there has been a strong tendency for all geological analytical requirements, especially for exploration and mining, to be carried out at commercial analytical laboratories. In recent years there has been a tendency for mines in South Africa to move in the same direction. This paper discusses the factors that need to be taken into consideration when a new laboratory is being planned and automation is an option. The planning of the laboratory at the new Langer Heinrich Uranium mine in Namibia is discussed considering these factors. 2.0 REQUIREMENTS OF A MINING ANALYTICAL LABORATORY The purpose and requirements of a mining analytical laboratory are fairly obvious and can be summarised as follows :- 1. All mining operations must have access to analytical facilities, either in-house or commercial 2. The laboratory must be able to handle all the sample types submitted by the mining operation These can be mining, exploration and/or plant samples. They can comprise solids (rocks, bore-cores), slurries and/or liquids.

Jan 1, 2007

By H. D. Kessler, F. A. Crossley, J. J. Rausch

The titanium-rich corner of the system Ti-AI-V has been studied to determine the phase relationships in the temperature interval 600° to 1200°C. Metallographic examination of long time isothermally annealed specimens was the principal method of investigation. TWENTY-SIX alloys in the region 1 to 22 pct A1 and 2 to 11 pct V, and the temperature range 600° to 1200°C, were studied as part of a program on phase relationships and transformation processes of titanium alloy systems. Experimental Procedure Preparation of Alloys—Materials used in the preparation of alloys were high purity Bureau of Mines sponge titanium (103 Bhn), 99.7 pct pure V chips obtained from the Electro Metallurgical Div., union Carbide and Carbon carp., and 99.71 pet pure A1 in the form of granulated shot from Aluminum cO. Of The alloy ingots, weighing l5 g, were melted in a nonconsumable tungsten electrode arc furnace un-

Jan 1, 1957

By Genrich A. Denisov

Principles of ecologically friendly geo-technologies construction are formulated on the basis of the works of the leading scientists in the field of rational processing of mineral resources of the Russian Academy of Sciences. One of these concepts is a new direction in rotational disintegration of mineral and technogenic raw material with the purpose of effective subsequent enrichment. A large amount of practical experience has been accumulated in the industry on selective destruction by application of vibrational method on initial material with consideration of its physical-mechanical properties and mineral structure. This method is successfully realised in a conic inertial pulverisation devices constructed by Mekhanobr Institute (St.-Petersburg). A new construction of conical-inertial pulverisation with a modification of disintegration force has been developed recently at Mekhanobr Institute. It allows, in some cases, to increase selectivity of subdivision and to avoid over-disintegration. Advantages of “wet” subdivision methods in conic inertial disintegration devices are proved. The efficiency of such subdivision can be increased due to rational use of the phenomenon of a dislocation-dynamic diffusion. Its advantage is proved by the effect on disintegrated material by frequency-modulated variable electrical fields of low power. It was shown in industrial conditions, that the productivity of the spherical mill can be increased by 10 %, and that it also prevents ecologically harmful surface active substances (SAS) in milling zone and it reduces the dust content in the air. The techniques of tentative estimation of efficiency of various proceedings technogenic materials and their classification are created. The scientific fundaments of rational, ecologically friendly technology of processing and regeneration of various kinds of technogenic raw material are developed. A number of effective technologies on processing of wastes is developed and inculcated in concentration factories and metallurgical factories.

Jan 1, 2003

By F. Dahl, P. Raleigh, J. Holzhauser, B. Nilsen

Tunnel excavation using tunnel boring machines (TBMs), has become increasingly common in recent years, despite the fact that precise evaluation of certain risks have not kept pace with the use of these machines. One of the risks easily overlooked by Engineer and Contractor alike are the effects of abrasive ground on the costs and schedule of a given project. The impacts of worn and damaged TBM cutter heads have been observed on hundreds of tunnel projects around the world. It would appear that a reliable prognosis of the abrasiveness of soils on a project would be of great importance for designers, clients and contractors alike. Several well acknowledged test and prognosis methods already exist for rock, however there is only very limited knowledge available to describe the abrasiveness of soil and its impact on soft ground TBMs. This paper will examine approaches to this problem and suggest a new approach based on a current project undergoing design.

Jan 1, 2007

By S. Lohmeier, D. Gallhofer, B. G. Lottermoser

Reprocessing of historic gold tailings is a common activity in South Africa, while base metal tailings offer similar reprocessing potential. The historic base metal tailings of the Namib Pb–Zn mine (Erongo Region, Namibia) still contain valuable resources of Pb and Zn in carbonate-rich matter. Micro-analysis of primary ore minerals identifies some galena as argentiferous and sphalerite as the principal host of Cd. This study demonstrates that knowledge of primary ore mineralogy helps to reveal the hosts of valuable commodities (Ag, Cd) and that field-portable X-ray fluorescence tools allow precise and accurate determinations of major and minor elements like Zn and Cd in such carbonate-rich material. Although there are limitations to directly determine the contents of certain element (i.e., As, Sb, In), linear correlations allow prediction of the likely abundance of these elements. Providing that the inter-mineral and inter-element relations are understood and there is consistency in sampling and analytical methodology, portable X-ray fluorescence analysis is an effective method to evaluate the chemical characteristics of base metal tailings for a range of major and trace elements.

Sep 9, 2024

By W. G. Pariseau

This Bureau of Mines report is an evaluation of the state of knowledge about gravity flow from bin hoppers, the most commonly used method of handling bulk materials where the force of gravity is used. The requirements for flow to be initiated and to continue, formulas developed experimentally or mathematically from various assumptions to describe the materials flow, and the question of whether or not a material will flow over the entire cross sectional area of the bin hopper according to the flow regime developed are the primary areas discussed. The work of A. W. Jenike, whose pioneering investigations raised bin hop- per design from the trial and error state, is examined in depth and its limitations and assumptions are pointed out. Bin hopper design depends heavily upon prior experience, and suggestions for further studies of bin hopper flow to include the effects of feeders are made.

Jan 1, 1972

By W. R. Chambers

A wide variety of mining conditions exists within the South Midlands Area and across this range of conditions more than one half of the mines are highly susceptible to spontaneous combustion. Two thick seams in which the greatest risk exists are described and illustrated. The different heatings which take place are categorized by the locations at which they occur in the mines: additional special cases not easily categorized by location are discussed separately. The discussion for each category of heating follows the pattern of: (i) the reasons why it occurs; (ii) when it arises the means by which it is fought, and (iii) the preventive measures taken in an attempt to avoid its occurrence. Relatively new factors which may affect the incidence of heatings are highlighted and suggestions are made which may assist in reducing the number of incidents in the Area. A new method of continuous sampling, analysis and recording is described and mention made of an original method of interpreting carbon monoxide results with the aid of the computer. The first results from this work show that an early warning is given of an adverse change in trend several weeks earlier than with the present methods. Lastly, suggestions are made about the direction in which research might proceed to assist in reducing the special hazards created by several features inherent in the present methods of mining.

May 23, 1905

By Urie R. W

Fluidized bed roasting of copper concentrates from Mt. Morgan, Mt. Lyell, Mt. Isa, and Peko was performed in a 3 ft 6 in diameter, slurry fed, pilot plant roaster operated under autogenous conditions to produce calcines with desirable leaching properties. A 12 in. diameter, externally heated roaster, provided with a dry feed system, was also used.An account is given of important factors which influence roaster behaviour and performance, and the effects of operating variables on calcine composition and leaching properties are described. Due to copper ferrite formation, a maximum of approximately 50 per cent of the copper in the calcines may be in the form of CuO before the copper leach efficiency falls significantly below lOO' per cent. Recovery of gold by cyanidation of leach residues was consistently high and independent of roasting conditions.INTRODUCTIONIn traditional practice copper is produced by pyrometallurgical techniques when the ,copper minerals in the ore or concentrate are predominantly sulphides, and by hydrometallurgy when the minerals are oxidized. Copper smelting is most suited to large scale operations, and for many years small to medium size mines with sulphide orebodies have been interested ill; alternative processes.Since hydrometallurgical plants (ie. leaching and electrowinning plants) are essentially unitized, they may be scaled down in output without much loss in efficiency or increase in processing cost, and many proposals have been made for the application of this type of process following roasting of the sulphides to render the copper soluble. However, until the advent of fluidized roasting, it was not possible to control the roasting operations sufficiently precisely to produce calcines consistently of the required leaching characteristics.

Jan 1, 1961

As a result of the world depression and the consequent heavy fall in the price of tin, Malaya joined with other great tin producing: countries of the world in a restriction scheme that heavily restricted production from its individual mines. This condition, together with the knowledge that it was becoming more and more difficult in, Malaya to acquire further areas and so prolong the existence of a specific company's activities, induced Mr. H. G. Scott, managing director for the Siamese Tin Syndicate Ltd., to consider other possible sources of production. Mainly because of the conditions that obtained in Tasmania, he turned his attention to that country, where, not only could mining be carried on without restriction as to output, but where the incidence of the exchange position created favourable conditions for operation. The district selected for examination was that of St. Helens, on the East Coast of Tasmania, which district had behind it a long record of successful tin mining operations.PRELIMINARY OPERATIONS OF SIAMESE TIN SYNDICATE LTD. AT ST. HELENS.First of all the district was examined, and there was no lack of evidence to show that tin existed, although it was impossible to get down to quantities and values without an extensive prospecting campaign. For one thing, the physical features of the country seemed to be all wrong. There were no extensive alluvial flats such as a mining engineer...

Jan 1, 1934

By U. Richter

Conveyors are a highly effective means of transporting material over long distances. Recently there has been a trend toward long conveyor systems with high capacity single flights. These conveyor systems are an efficient alternative to costly truck fleets. Also with deeper mines, the use of diesel driven trucks becomes more difficult. Another trend is in underground mining, where conveyors are an efficient alternative to drift hoists or dedicated rail systems.

Jan 1, 2012

By S. Frimpong

Hydraulic shovels are widely used for primary production in surface mining operations. Variability in material diggability, unstructured mining environments and limited space and operator inefficiency affect the performance of these shovel excavators. Dynamic models of the hydraulic shovels are essential for understanding and improving machine performance. This paper contributes to this subject area by advancing hydraulic shovel kinematics and dynamics using the modified Newton-Euler method. A virtual simulator is developed to simulate the hydraulic shovel performance in the ADAMS environment. The simulator is validated with data on shovel geometry and the physical and mechanical properties of a formation in a surface mining environment. The results indicate that a shorter digging time increases the shovel operating power requirements, and that the required peak power increases by 100% when the digging time reduces by 50%. Simulation results also show that a shallow trajectory facilitates the digging process, with 50% reduction in peak power requirements compared to a deep one. This simulator provides a powerful tool for performance monitoring, excavation process designs and structural optimization of hydraulic excavators. This work also forms the basis for developing comprehensive simulator models for automated shovel operations in constrained mining environments.

Jan 1, 2005

Discussion continuing that published in Trans.I.MIn.E ., 1915, vol.L, p.449 and 1916, vol.LI, p.166, included contributions by Smith W., McLaren R., Gibson J., McCreath W., Sneddon J.B., Kirkpatrick J. and Mowat D.M. and a written response by Black J.N.

Dec 1, 1916

By G B. Smith

Barrick (Australia Pacific) Limited initiated a trial of Caterpillar’s Minegem autonomous loader technology in 2009 at the Kanowna Belle mine in Kalgoorlie. Autonomous loader technology offers the potential to improve loader productivity, reduce operating costs and improve safety through removing personnel from the mine operating environment. This paper discusses the implementation of the technology at the mine site, the data collected during the trial and quantifies the benefits of using automated loader technology in comparison with teleremote loader operation. The lessons learned from the trial and work planned for the future in respect of this technology is also discussed.

Mar 21, 2011

By Paul Richardson

This paper will review several projects completed during the period from 1976 through 1984 which have been carried out utilizing big hole drilling concepts. The projects discussed will be from various industries to demonstrate the extent that big hole drilling methods are being used along with the current state of development. There will be a discussion of projects planned for the future where big hole drilling methods are the only technology being considered. Also included in the discussions will be an overview of the most recently completed heavy oil recovery project. During the next decade, big hole drilling methods will be used more and more in all industries where underground access is required. The safety, speed and economics associated with shaft sinking using drilling methods are becoming more and more recognized and the technology is rapidly becoming an accepted shaft sinking method.

Jan 1, 1985

By H. Ranjbar

The Darrehzar porphyry Cu deposit is situated in the Urumieh-Dokhtar magmatic suite of Central Iran. The REE and trace element data suggest that the deposit lies within a continental margin setting. Phyllic and propylitic alteration are pervasive in the area but potassic and argillicalteration are not readily recognized on the surface. This is possibly the result of super gene weathering of the surface rocks or because of an intense phyllic overprint. Poor soil development and abundant outcrop make the area suitable for a case study of lithogeochemical exploration technique for Cu deposits. A total of 262 rock samples was collected over the area and analyzed for 15 elements. The geochemical data cor-relate with the mineralogical composition of the rocks with the phyllic zone being marked by high-er concentrations of Si, Al, K, and by a high sericitization index while Ca, Mg, Sr, total Fe and Mn are more abundant in the propylitic zone. The lithogeochemical study indicates a metal zonation from a Cu + Mo-rich core to a Zn + Pb ± Ag-rich outer zone. Principal component analysis is useful for separating element associations, which in turn reflect the alteration halos. Principal components 1 and 2 depict alteration zoning, where-as 3 shows an association of Cu and Mo, that roughly defines the mineralized area.

Jan 1, 1997

By K. C. Armstrong, A. B. Cron, L. A. Melis

"The Johnny Mountain gold mine in northern British Columbia, owned by skyline Gold Corporation, has been in operation since August 1988. Mill operating difficulties at the start of the operation resulted in a depleted cash flow situation and quick improvements were required to generate a self-sustaining financial basis of operation. In October 1988, Melis Engineering Ltd. was contracted to identify metallurgical difficulties, implement necessary modifications, and undertake mill operations and personnel training in order to achieve production targets.This paper presents the operating difficulties which existed at start-up and describes the methodology used to overcome production problems. Metallurgical testing results are described along with the modifications made to the milling circuit to suit ore metallurgy. Plant changes led to the operation of a simple gravity/flotation circuit to recover gold as bullion and in a copper concentrate. Operation of the originally installed cyanidation circuit was discontinued. This contributed to substantial savings in operating costs and virtually eliminated environmental problems. PROPERRTY LOCATION ANR DESCRIPTIONThe Johnny Mountain mine site is located in northern British Columbia along the Iskuit River about 60 km east of Wrangell, Alaska and 275 km north of Terrace, B. C.. A location map is presented in Figure 1 and a site plan is shown in Figure 2. The complex is located on a mountain plateau about 3, 600 feet above sea level. The plateau is flanked to the north by Johnny Mountain and surrounded on the other sides by steep cliffs."

Jan 1, 1990

By Jim Frazier

Tradition has often dictated low design load stresses on piles. Such traditions often developed prior to modern static or dynamic pile testing methods and perhaps result from a few limiting situations. These low stress limits were then broadly applied, even in cases where the piles could carry substantially higher loads. With sufficient testing to prove the design, higher design loads may present significant overall savings to the project owner. The cost of the testing then becomes an insignificant cost compared to the potentially great benefit of increased pile loadings. To confirm higher load possibilities for driven piles, the pile is tested either statically or dynamically. Further savings and increased testing efficiency result from remote dynamic pile testing. This paper presents a project where design stresses were considerably increased as a result of additional testing and use of remote dynamic pile testing equipment.

Jan 1, 2002

The Tenth International Conference of Directors of Safety in Mines Research was held in the United States from September 28 through October 2, 1959, at Hotel Webster Hall, Pittsburgh, Pa. The Conference was organized by the Federal Bureau of Mines. In accord with the program outlined at the Ninth Conference (1956, Heerlen, Holland), the papers submitted dealt with the following three subjects: 1. Safety of coal mine explosives 2. Explosion hazards in mines 3. Ignition and fires in mines Seventy papers were presented. There were eight technical sessions followed by an extended tour of the Bruceton facility of the Bureau of Mines on October 2. Simultaneous translation was provided in the three official languages of the Conference--English, French, and German.

Jan 1, 1962