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By G. St. J. Perrott, N. A. Tolch

"The measured strength of an explosive depends to a certain extent on which it is determined. An earlier investigation showed the relative propulsive strength of dynamites as determined in one type of apparatus, ballistic pendulum.4 The aim of this paper is to precept strength data on these same dynamites determined in another type of apparatus, the Trauzl lead block, and to compare the results with those of the ballistic pendulum. Trauzl lead block have been in use many years for the determination of thy strength of explosives, under moderate confinement.5 The common practice is to shoot 10 grams of explosive, in tinfoil wrapper,- and then to measure the volume of the cavity produced by the shot. The volume of the original borehole is deducted from the gross expansion and sometimes a correction is made for the expansion produced by the detonator. Dry sand is used for stemming the charge.It has been found that the expansion in Trauzl blocks is not strictly proportional to the charge. Naoum5 believed that for scientific accuracy the charge should undoubtedly be regulated to give the same average expansion for each sample tested, but for expansions of 200 to 400 cubic, centimeters the deviation from proportionality is not sufficient to give results appreciably in error.Neubner7 found that the proportionality curve is tangent to the charge-expansion curve at about 300 cubic centimeters expansion, provided that no deductions are made for the volume of the original borehole or the effect of the detonator; the total or gross expansion is proportional to the charge between expansions of 250 to 350 cubic centimeters without serious error."

Oct 1, 1930

By Darby H. P, Vincent R. J

Sydney's Eastern Suburbs Railway from Central to Bondi Junction required the construc- tion of 10.4 km of single-track tunnel and five underground stations. Much of this work took place beneath the commercial centre of Australia's largest city. This paper discusses the general precautions taken and the specific design solutions made for such problems as support of a 15-storey building with foundations several metres above the excavation to ensure negligible differential settlement, excavation immediately below running tunnels, underpinning of multi-storey buildings, tunnelling under massive masonry retaining walls and demolition and rebuilding of part-completed structures.

Jan 1, 1981

The Pogo Mine, near Delta Junction, Alaska is a 2500 TPD gold operation employing processes including grinding, gravity, rougher flotation, leach, CIP, and E/W. An OCS(Optimizing Control System) expert control system has been implemented on rougher flotation in early 2008. The OCS system communicates with the Plant DCS(Distributed Control System) through OPC(OLE for Process Control) communication. The initial strategy was to control the flotation cell froth level set points to achieve target froth velocities. This strategy was enhanced by controlling both level and air flow setpoints. The flotation cell air and level are adjusted to reach cell pulling rates (froth velocities). The pulling rate setpoints for each cell are determined based on downstream capacity (concentrate surge tank level). The effect of pH and upstream disturbances is also taken into account in adjusting the air and level setpoints. Feed forward compensation is employed down the flotation row to minimize disturbances.

Jan 1, 2009

This paper discusses a number of examples of how environmental factors have been incorporated into the water management aspects of mining projects. One example is the Kingston Lignite Project in the South-East of South Australia where the most significant environmental issue was considered to be the effect of drawdown from mine dewatering and depressurization upon the use of groundwater. By proposing an alternative mining method - the use of floating dredges rather than a two-pass dragline method - drawdown effects would no longer be a concern. A second example is the Pine Creek Gold Mine in the Northern Territory. In this case the principal area of interest from an environmental viewpoint was water management - in particular effluent disposal, contaminated seepage from overburden and tailings, and project water supply. Through an integrated approach to the management of wastes and water the potential for water quality impairment was significantly reduced and external water supply requirements were also significantly reduced.

Jan 1, 1987

By D. J. Parker

On Thursday, March 18, 1937, the country was shocked by news of a terrific explosion at the New London, Tex., school, which caused the death of 280 pupils avid 14 teachers. The explosion occurred at about 3:05 p.m. in the largest of the 11 school buildings on the campus. Fire 1 shows this building, marked "Main high school building", with respect to other buildings, pipe lines, oil wells, and gas lines or the property.

Jan 1, 1937

By D Preedy, J K. Claflin, S R. La Brooy

A gold mine in north-eastern Africa has expanded throughput from 5 to 10 Mt/y in recent years. The original carbon regeneration kiln was incapable of achieving required throughput or meeting process conditions to reactivate the carbon due to heavy fouling by high molecular weight frothers and collectors. A new high temperature kiln was required.The design criteria for the carbon reactivation kiln and associated equipment were revised, then implemented in close cooperation with a kiln vender who had previously supplied kilns operating successfully on highly fouled carbon. The result is a whole facility, holistically designed to achieve the technical criteria.The new carbon reactivation facility has been operating since 1 July 2014. What have we learned? What has performed to expectations? What could be done better?This paper presents lessons learnt regarding the design, implementation, operation and maintenance of the Ausenco Carbon Reactivation Kiln. ‘Lessons’ are associated with threats and opportunities (risks) that have that have been realised. The importance of identifying and managing risks for even small straightforward projects is demonstrated.CITATION:Claflin, J K, La Brooy, S R and Preedy, D, 2015. Lessons learnt and performance – installing and commissioning an Ausenco carbon reactivation kiln in Africa, in Proceedings MetPlant 2015, pp 163–174 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

Sublevel open stoping (S.L.O.S.) was introduced at Rosebery in 1972 in the wider ore blocks below 14 level, largely replacing cut and fill methods which had been in use up till that time. During 1973/74 the method produced 10% of primary stoping tonnes, and by 1981/82 it increased to 65%. Because of the increasing reliance placed on sublevel open stoping for primary stoping production, every effort was made in both planning and operating to: - maximise ore recovery and reduce dilution - increase productivity - reduce costs.

Jan 1, 1982

Albert Sauveur, Cambridge, Mass. (written discussion).— In his introductory paragraph, the author states that he has come to bury Beilby, not to praise him. The paper, however, gives the impression that while he may have dug the grave, Beilby is still at large. I am not one of those whom the author calls enthusiastic supporters of Beilby's amorphous theory and in support of this claim quote from a book I am writing: "Attractive as the amorphous theory is, and notwithstanding the ability with which it has been presented and the renown of its sponsors and supporters, it should not be accepted without reservations as a demonstrated fact.... So long as it explains more satisfactorily than other theories a greater number of phenomena in which it may play a part, we should use it in preference to others as the best available. Let us avoid the danger, however, into which too many fall, of accepting as indisputable truths, statements and theories emanating from those whom we hold in great esteem. It is not what those men themselves would wish us to do. I am entitled, I think, to occupy a position in the middle ground. Neither should Howe be classified with the enthusiastic supporters for he has written that the theory should be classed rather among the precious working theories than among those firmly established," a very wise and prudent statement. Jeffries, on the other hand, I would not hesitate to describe as an enthusiastic supporter. The author reproaches the advocates of the amorphous theory with having taken whatever properties they needed and with having assigned them arbitrarily to the hypothetical amorphous phase. He then applics their method to small crystals. If the existence of an amorphous phase is assumed, its greater tenacity and greater hardness is satisfactorily explained in the words of Howc: '(This greater strength is natural, because the amorphous state lacks the cleavages and slip planes which weaken crystalline substances." Can the greater strength and hardness claimed for small crystals be as satisfactorily explained? Nor do I think that the cold deformation of metals through successive slips within the crystalline grains can he accounted for as acceptably by the "small crystals theory."

Jan 1, 1923

By Bruce Macdonald

Operational monitoring of slope stability can be achieved by space based InSAR monitoring platforms. Natural and man-made rock slopes are monitored using a novel stack-based InSAR method that exploits both persistent point scatterers (PS) as well as coherent distributed scatterers (DS) such as areas of pavement and sparsely vegetated surfaces. The new method, Homogenous Distributed Scatterer (HDS)-InSAR identifies InSAR targets by using adaptive multilooking of statistically homogenous pixel neighbourhoods combined with thresholding the differential temporal coherence of each target candidate with respect to its surroundings. HDS-InSAR preserves PS and therefore forms a direct generalization to our proven DualScale-PSI method. The density of HDS exceeds that of PS by more than an order of magnitude often providing essentially continuous coverage over urban and industrial landscapes featuring a mix of infrastructure with mostly bare soils or rock surfaces. The improved coverage enables better definition of surface motion and underlying geology, which will lead to superior interpretation of the geophysical mechanisms causing the surface deformation, e.g. through improved integration with 3D deformation modeling. We illustrate the performance of our new HDS-InSAR method compared to DualScale-PSI using displacement results from Vancouver, Canada; Bingham mine, USA; and the Palabora mine, South Africa.

Jun 1, 2012

By G. W. Poling

This paper evaluates current environmental protection legislation, guidelines and criteria, focusing mainly on the land and water disposal of mill tailings. Effluent criteria and regulatory mechanisms are proposed, and submarine tailing disposal is discussed at length. The importance of basing regulations on the best available rationale is stressed.

Jan 1, 1979

By C. N. Baker

The design and construction of drilled piers through water bearing and caving soil conditions are discussed. The need for close cooperation between the design engineer and contractor in both the design and construction stage is outlined. Four case histories illustrating the design and construction considerations for four different problem soil and ground water profiles are presented, including the field testing and observation procedures that were utilized to confirm that the design inten. was accomplished. Requirements advisable when placing concrete under water in a cased environment and when placing concrete under slurry in an uncased environment are described.

Jan 1, 2010

By J. I. Adetunji

Mining activities usually affect the soil, subsurface layers, water resources, the atmosphere and in general the lives of the people. The effects can be mechanical, biological, ecological and economical in nature and these effects can be characterized by their intensity, frequency, duration and scale. In Oyo State, Southwestern Nigeria efforts are being made to employ a sustainable method in the exploration and exploitation of abundant industrial minerals present in the state. The minerals exploited include talc, clay, marble, sillimanite, tantalite, niobium, beryl, tourmaline aquamarine, rock aggregates, etc. Results of this sustainable approach show that the environmental impacts of surface and underground mining of industrial minerals are not spread far beyond the mines site acreage. More lands are being reclaimed, the amount of dust released into the air has been minimized, the quality of sewage waters produced during operations are minimized, top soils removed during subsurface mining are preserved, the tonnages of minerals exploited are being monitored and controlled. All these point to a positive development in practicing sustainable methods in mineral exploitation to meet the developmental needs of the Oyo State at present and to conserve for the future.

Jan 1, 2003

By Sidney Katell

This Bureau of Mines study estimates capital investment, operating costs, and selling prices for three underground bituminous mines producing coal with annual production ranging from 1.03 to 3.09 million tons. It is assumed that the mines have a 20-year life. Wages and union welfare payments are considered as of November 12, 1973, under the Bituminous Wage Agreement of 1971, and costs for material and equipment are based on 1973 indexes. Initial capital investment ranges from $12,938,200 for the 1.03-million-ton-per-year (MJ.Vl tpy) mine to $31,435,500 for the 3.09 MM tpy mine. Total capital investment ranges from $21,607,200 to $51,982,000 for the same mines. Corresponding selling prices for the coal range from $9.11 to $8.06 per ton, assuming a 12-percent discounted cash flow rate of return after Federal income taxes.

Jan 1, 1974

By Robert U. King, John W. Vanderwilt

THE Climax molybdenite deposit in Lake County 100 miles southwest of Denver is located in the central part of the mineral belt extending north-easterly across the state. Principal geographic features and geology are shown on Fig. 1. The first period of molybdenite mining, which began in 1918, ended in April 1919 because of limited demand and a price drop to about 724 per lb. During this time the ore came from the Leal level and surface outcrops at a higher elevation. Rate of mining was 250 tpd and several million tons of ore averaging 0.7 pct molybdenite were developed. Since April 1924, when the second period* began, Climax Molybdenum Co. has been the only operating company. Production in 1924 was 400 tpd and finding ore was a continual problem. When the White tunnel was extended, however, further ore was encountered. The orebody was thought to be tabular until 1926, when B. S. Butler recognized the relation of the developed ore on the Leal and White levels to a central area of fine-grained hydrothermal quartz, and by 1929 diamond drilling had blocked out indicated ore reserves in excess of 100 million tons.

Jan 1, 1955

By Ian William Wark

DIFFERENT parts of the world in which mineral separation by flotation is practiced experience vastly different natural temperatures, and in some districts there is a big difference between summer and winter tempera-tures. It will be shown in this paper that the temperature is of con-siderable importance where it is desired to separate pyrite or arsenopyrite from other minerals. It is probable that some of the differences obtained in the flotation of these minerals at plants working under otherwise similar conditions are due to temperature variations. The influence of temperature on the flotation of galena, chalcopyrite and sphalerite by xanthates is less marked than its influence on pyrite flotation.

Jan 1, 1938

By Reed S. C. Rogers, Robin P. Gardner, Kuruvilla Verghese

The development and use of short-lived radioactive tracer methods for the onstream determination of residence time distributions in large-scale ball mills is described. Tests are reported on a pilot-plant ball mill with 0.43 m diameter and 0.86 m length and on an industrial mill with 1.83 m diameter and 2.74 m length. Tests with different tracer feed sizes indicate that the residence time distributions on both mills are independent of charge particle size. Similar tests are planned for a large ball mill of 4.57 m diameter and 9.30 m length. No safety problems were encountered in these tests and none are anticipated in tests of the larger mill.

Jan 1, 1981

By Hagen G, Uhlig H

In the Federal Republic of Germany the thermal environment in underground coal mines has deteriorated progressively over the past years. The number and capacity of refrigeration plants have increased correspondingly. In recent years high capacity spray coolers have been used in addition to conventional cooling coils.

Jan 1, 1988

By G. Geremia, M. I. Serrano, L. Costa, Strohaecker

The advances in electronics and the development of more efficient algorithms, allow for the designing of more complex and sophisticated automated systems. The new devices include lighter, faster, reliable, and stronger robot manipulators. One available technology, with relatively low cost, is a simple robot manipulator controlled by remote control. The device has been designed to be used in both mining and law enforcement, where it can be useful for inspection, rescue, gas analysis, and even to manipulate dangerous objects, such as explosives. The applications may even include the rescue of trapped miners in risky environments. The major advantage is the fact that the robot can be controlled with a remote and monitored through a video camera, minimizing human exposure to hazardous areas, where robots can perform tasks in an aggressive atmosphere and confined spaces. This article presents a mining robot manipulator controlled by remote control, using video cameras for positioning and sensors for movements, which are located on the operator's arm. With this system, it is possible to create a sensation of virtual reality, allowing easy operation for anyone trained in dealing with explosives, rescues, or other dangerous tasks. Blasting and mining are becoming perfect applications for robots, and its use should increase very soon. The results are discussed and presented for the brand new Xiru 01 robot manipulator.

Jan 1, 2010

By J. Wesley Pullman

It is stated by Dr. Tuttle in a paper read before the New Jersey Historical Society, that the celebrated Dickerson mine at Succasunna, Morris Co., N. J., yielded ore, about as early as 1710, for use at the Whippany forge, on Rockaway River, between Rockaway and Boonton. The ore was, for some time, free to all who chose to dig it. The tract embracing the Dickerson mine mas taken up, on account of its minerals, in 1713 or 1714, by John Reading, who sold it in 1716 to Joseph Kirkbride. John Jackson built a forge in 1722 on the Rockaway River a mile west of Dover. The ore here worked was probably chiefly from the Dickerson mine, but a portion may have been Hibernia. Hon. E. D. Halsey, of Rockaway, K. J., writes me: It is quite possible that the ore was at first taken from the outcrop of Hibernia by anybody who wanted it. The property first had an owner, May

Jan 1, 1886

I will confine my remarks to normal computers that people interact with, rather than built-in processors which exist in every watch and washing machine these days. I will also confine myself to computing in the technical side of mining. Bu

Jan 1, 1998