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By Li Tiemin

It is one of important tasks in research of vibratory pile driving to increase speed of pile driving and depth of pile driving -- this means to increase capability of penetrating hard layer. In general, vibratory pile driving hammer make pile be situated in vibratory situation to drive pile by means of weight of hammer and pile, but the depth of pile driving and capability of penetrating layer are limited by dead weight of hammer. This paper introduces a new kind of vibratory pile driving hammer which differs from general ham­mer. A set of pressing system is attached to hammer and pile driving frame. The pull of winch installed on frame passing guide pulleys bring downwards press to pile through absorbing system of hammer. The practice and comparison test have showed that the new hammer is faster in pile driving and bigger in capability of penetrating layer than general one. Now, the vibratory pile driving hammer with pressing device has been applied widely in China. RESUME: The vibratory pile driving hammer based on vibratory principle to design have applied wide­ly in foundation engineering in many countries over the world. In order to suit the needs of deep foundation, at present, how can quicken speed of pile driving and increase depth of pile driving have become even more value to many countries in the world. This paper introduces a kind of rapid vibratory pile driving hammer which can drive pile deeper and more faster comparing with common vibratory pile driving hammer. Therefore, a kind of simple and reliable method has been offered for rapid vibratory pile driving in deep foundation.

Jan 1, 1991

By G. C. Hall, B. E. Hobbs

Giant gold deposits are considered products of crustal-scale systems. Reduced fluids stored in mid to lower crustal reservoirs were discharged into mid to upper crustal sites of deposition. Elements of the architecture include crustal-scale structures, reduced packages of rock and regional seals. Gas-rich aqueous fluids were common but non-aqueous fluids may have been significant in the deeper parts of the systems. Fluid fluxes in over pressured domains were maintained by porosity waves. Abnormal heat input from the mantle may not be required once the systems were perturbed. Fluid-mixing and hypogene enrichment were probably the most significant precipitation processes.

Jan 1, 1999

By G. Auld

"A simple method is presented whereby the additional quantity and static pressure necessary to compensate for ventilation duct leakage may be estimated using the circular reference functions of modern spreadsheets. Favourable comparisons have been made to the National Coal Board (United Kingdom) design charts and to a case study analysis. IntroductionIn mining, most ducted systems are applied to the development of access tunnels, and most of these systems leak to some extent. When the ventilation duct fails to deliver the required quantity of air to the work place, there is a significant contribution to the development costs, either directly or indirectly.Directly — More air and more pressure are required to compensate for the leakage, more capital development (ventilation shafts, parallel drives) are required because ventilation systems cannot push the fresh air far enough, and longer re-entry times to ensure toxic blast fumes to be diluted.Indirectly — There is a reduction in productivity because of the inclement atmospheric conditions, and/or closure of development ends because of unacceptable atmospheric conditions at the working place. This has been exacerbated over the last few decades because of the increased use of diesel equipment of ever increasing power, and the more stringent Occupational Health and Safety requirements demanding more air flow per kilowatt of diesel power.The leakage from a duct must, therefore, be reliably estimated in order to assess the effectiveness and construction of the system; assess the effectiveness of the maintenance or repair of the duct; appreciate the cost of the leakage, and therefore apply effective maintenance and installation procedures; and engineer safer, healthier and more cost-effective ventilation systems."

Jan 1, 2002

By Robert L. Lagace

An investigation is made of the feasibility of developing compact transmit antennas and/or other means to efficiently couple VLF to MF band radio energy between portable wireless communication units in coal minus. The completely wireless communication ranges between two portable radios equipped with practically-sized reference loop antennas in representative coal mine environments are estimated. Antenna technology is assessed with respect to transmit moment, range, intrinsic safety, battery and wearability requirements to determine the most suitable antenna types for use by miners. It is concluded that air-core bandolier loop antennas, and perhaps ferrite-loaded loop antennas, having peak transmit moments of about 2.5 ampere-m2 will be the most effective antenna choices for portable units. This choice, however, will not allow the range goal of 1350 feet to he attained in mines having unfavorable signal attenuation and noise environments. Rectangular air-core loops are compared with grounded horizontal-wire and vertical-wire mode exciters for fixed station applications. The potential for significantly increasing the wireless communication range by inductively coupling to communications and power lines in a mine is evaluated and found to be considerable based on theoretical coupling equations. Lastly, the theoretical performance of a hybrid noise cancelling diversity receiving technique that utilizes both the electric and magnetic field components of the ambient noise to improve the receiver output signal-to-noise ratio under certain adverse conditions is estimated and shown to be favorable when the magnetic and electric field noise components are highly correlated.

Jan 1, 1977

By Gray Mullins

The construction of drilled shafts as well as other cast in place foundation alternatives relies heavily on good practices from the contractor, engineer, and inspector in order to produce a quality foundation element. As many of the installation methods involve blind concreting processes, it is difficult to be certain of an intact concrete mass of the intended dimensions. A new integrity test has been developed that provides additional insight into the integrity of drilled shaft concrete. By measuring the temperature throughout the shaft via standard access tubes, the measured temperature profile can be compared to the normal signature associated with a shaft of the specified size. This article provides an overview of the new method development, test procedure, analysis, and results.

Jan 1, 2010

By Marcos Paulo Kohler Caldas

O desenvolvendo da indústria de eletroeletrônicos associada ao barateamento dos produtos tem reduzido a vida útil de equipamentos levando a uma geração elevada de resíduos de equipamentos eletroeletrônicos (REEE). Um componente desse resíduo são as placas de circuito impresso, que possuem em sua composição altos teores de metais, que podem ser recuperados através de processos de reciclagem. O presente trabalho busca caracterizar placas mãe de computador, determinando sua quantidade de material orgânico, cerâmico e metálico. As placas foram direcionadas para cominuição, que foi realizada em moinho de facas com grelha de 9mm, seguida por um moinho de martelos, atingindo uma granulometria menor que 2mm. A amostra foi então quarteada, para uma maior homogeneização e passou por ensaio de digestão em água régia. O licor resultante foi diluído para determinação do teor dos metais Ag, Al, Au, Ba, Ca, Cu, Fe, Ni, Pb, Sn, e Zn utilizando espectrometria de emissão óptica por indução de plasma (ICP-OES). O sólido filtrado, também resultante da digestão em água régia, passou por um ensaio de perda ao fogo a 800°C por uma hora, para determinar o teor de material orgânico. Os resultados indicaram que o Cu é o metal de maior concentração com 22,5% na placa de circuito impresso e que a mesma possui 43,7% de metais, 31,9% de polímeros e 24,4% de cerâmicas. A prata representa 0,04% dos metais e sua obtenção será realizada na forma de nanopartículas a partir de rotas hidrometalúrgicas.

Aug 8, 2018

By K. -C. Han, S. -Y. Kim

This study was carried out in a bid to survey Ganboke gold mine in Pala, Mayo-Kebbi Province, southwestern Chad. The Ganboke mine is now being prepared for investigation and development, and the research sought to perform rock properties tests of relevant rocks through its geological survey, rock mass evaluation, and in-situ and laboratory tests and analyze the stability by the means of limit equilibrium method, thereby suggest appropriate methods to design the pit slope and individual benches in Ganboke mine. Targenting GS1-GS1' section with the depth of 180 m and GS2-GS2' section with the depth of 150 m in the survey area, we set the height of the bench at 10 m and 15 m, and the angle of bench at 60o and 70o, respectively, and then reviewed the stability for dried condition and saturated condition. The result of examination indicated that it would be appropriate to set the bench height at 10m and the bench angle at 60o in developing the mine slopes concerned. Cette étude est réalisé dans le but de faire des recherches sur Ganboke mine d'or dans Pala, Mayo-Kebbi Provence, Tchad sud-ouest. La Ganboke mine est actuellement en train de étre disposé à la investigation et le développement, et la recherche a cherché à accomplir les tests de la propriétè des roches par l'intermédiaire de la étude géologique, la évaluation de la masse rocheuse, et in-situ et les tests de laboratoire et à faire l'analyse de la stabilité au moyen de la méthode d'équilibre limite, de ce fait à proposer le methodes propres à faire le plan de la pente et les gradins individuels dans la Ganboke mine. Concernant la section de GS1-GS1' avec la profondeur de 180 m et la section de GS2-GS2' avec la profondeur de 150 m dans l'aire d'étude, nous mîmes l'hauteur du gradin à 10 m et 15 m, et l'angle du gradin à 60o and 70o, respectivement, et alors nous avon reconsidéré la stabilité pour la condition sèche et la condition saturé. Le résultat d'examen a indiqué que il pourrait être propre de mettre l'hauteur du gradin à 10m et l'angle du gradin à 60o en développant les pentes de la mine concerné. Diese Forschung wurde um das Gold Bergwerk zu überschauen in Pala, Mayo-Kebbi Provinz, der Südwesten Chad ausgeführen. Das Ganboke Bergwerk ist jetzt zur Erforschung und Entwicklung vorgebereiten worden, und die Forschung suchte zu ausführen die Prüfungen der Felseigenschaft durch geologischen Überblick, Felsmassewertbestimmung, und In-situ und Lavorversuch auf, und analysieren die Stabilität mittelst der Grenzegleichgewichtsmethode, da-durch schlug die angemes-sen Methoden zu entwerfen die Böschungen und die einzelnen Bänke im Ganboke Bergwerk vor. Für den Abschnitt GS1-GS1' mit der Tiefe von 180 m und GS2-GS2' mit der Tiefe von 150 m in der Überblickfläche, wir setzten die Bankhöhe an 10 m und 15 m, und das Bankwinkel an 60o und 70o, beziehungsweise, und dann zurückblickten die Stabilität für die getrockneten Bedingungen und die gesättigten Bedingungen. Das Ergebnis der Untersuchung anzeigte daß es würde angemessen sein zu setzen die Bqnkhöhe an 10m und das Bankwinkel an 60o in der Entwickelungen vom Bergwerk be-teiligt.

Jan 1, 2003

By Kenneth A. Pidgeon

This paper presents a case history on mitigating vibration problems associated with the installation of steel sheetpiles. The project in-cludes installation of steel sheetpiles for a utility trench within 40 feet (12.2 meters) of a very sensitive manufacturing facility. Numerous production line quality control instruments and manufacturing processes within the manufacturing facility are extremely sensitive to vibrations. To minimize the impact to the owner, we specified that the contractor perform a vibration study using different types of pile hammers. The results and conclusions of the vibration study are presented in this paper.

Jan 1, 1995

By Paul W. Johnson

A computer program for calculating capital and operating costs from material and energy requirements and equipment costs for use in preparing cost estimates for metallurgical process evaluations has been written by the Bureau of Mines' College Park process evaluation group. The program permits rapid recalculation of processing costs when changes of data or equipment are desired, and produces tables of capital and operating costs suitable for publication. Equipment cost summary tables for each process section end supplemental information for input-data checking is included in the computer printout. The program is written in Fortran IV except for several subroutines which are written in machine assembly language for the IBM 7094.3 With a few modifications, the program can be used on other computers.

Jan 1, 1969

By M. A. Hardie

"CASES and mixtures of them are so common and so much a part of everyday existence that they become so taken for granted that their individual characteristics and idiosyncrasies rarely become of curiosity to others than those involved in tl1eir production, processing, treatment, transportation, and for utilization. The use of the most common and universal mixture of gases -air -is begun at birth by ail living creatures and their discontinuation of its use terminates existence. Modern man rides on air in his tires, rides through it for high-speed transportation, and uses it for his comfort in the heating and air conditioning of his domicile. It is neither the aim nor the in-tent, in the next few moments, to provide a panacea for even a portion of the problems inherent in the gas industry nor to delve deeply into any particular facet of its diversities. The purpose is primarily to touch upon some of the peculiarities and generally to consider approaches to employ in the pursuit of solutions."

Jan 1, 1959

By L. Nahai

Overall mineral industry productive activity in Europe increased in 1965, following general upward trends in gross national product and total industrial production4 recorded. The gross national product of non-Communist Europe in market prices in 1965 was estimated at $572 billion and that of Communist Europe at $409 billion. However, the extractive sectors of the mineral industries generally did not fare as well as the processing sectors. In fact, a number of countries recorded lower production levels in this sector in 1965 than in 1964 and most countries had a lower growth rate in extractive industry output than in overall industrial output. Among the non-Communist nations of Europe, a general decline in coal production and lower levels of iron ore output in France, West Germany, and Luxembourg contributed significantly to the smaller growth rates or declines in extractive indexes. Where higher indexes were registered, this generally resulted from the performance of the petroleum and natural gas industry; exceptions were Greece, Norway, and Sweden. The decline recorded for Czechoslovakia was attributable entirely to poorer performance by that nation's coal industry.

Jan 1, 1967

By Robert Pack

INTRODUCTION SOONER or later in the development of any natural resource it becomes highly desirable to know the quantity of this resource in the country as a whole, as well as of the part that is being developed, for the general course and. conduct of the development work must be governed to some extent by the total supply available. An accurate estimate of the quantity of any natural resource is difficult to make; yet if one is diligent enough one can obtain a pretty accurate idea of the quantity of marketable timber, the acreage of tillable land, or the horsepower that may be developed from the streams, for these are things that may be measured. But any attempt to estimate the quantity of some mineral in the ground appears to enter the realm of imagination and it seems that the estimate can be nothing more than a blind guess. It may appear to be especially futile to attempt to determine the quantity of oil and gas that is available in the ground, for these minerals are so vagrant that even if the quantity now available should be known quite exactly, the quantity that will eventually be obtained may be much less, for certain losses in the extraction of both oil and gas are unavoidable, and just what these losses will be cannot be predicted. Though necessarily inaccurate, estimates of such mineral reserves are, however, of distinct value, for they summarize the existing knowledge of the deposits of the mineral and thus enable those who are interested in some industry that depends in one way or another on this mineral to formulate a rational commercial policy. Some time ago, when the price of gasoline suddenly rose in a rather spectacular manner, the writer was one of the U. S. Geological Survey geologists called upon to help to estimate the quantity of oil that could be obtained in the United States, for the fear had become widespread that perhaps the rate of increase in the price of gasoline was a measure of the rate of depletion of the supply of petroleum. It thus became his

Jan 8, 1917

Technical disputes, commercial negotiations and workplace/societal conflict are a natural part of doing business and just living itself. Conflict is everywhere û at home (between family and neighbours); in the workplace (between management, co-workers and unions), with contractors and with other companies; and everywhere at the community level, dealing with land access (pastoralists/farmers and indigenous/First Nation people), environmental protestors and NIMBY-ites - Civil Society in general. Exploration and mining companies, operating in more remote, less developed and culturally diverse regions, tend to encounter myriad areas of conflict (typically emotion-charged) and they are outlined. Dispute prevention, management and various binding and non-binding resolution techniques are discussed. The paper gives a general overview of the ADR nomenclature and framework (mediation, conciliation, expert determination, adjudication, arbitration and litigation) encouraging technical professionals to participate. Its thesis is that lawyers should not necessarily be the first port of call when problems arise between the mining workforce, contractors, joint venture partners, purchasers of prospects/mines, traditional land owners, protest groups, etc. If the matter must be litigated, the role of the expert witness is critical in pretrial planning, negotiations, mediation and litigation management, so a few guidelines are provided. Whilst dispute resolution has a legal context, the paper is written from an AusIMM technical professionalÆs perspective, emphasising practical long-lasting pragmatic solutions.

Jan 1, 2006

By Chen Song

Keywords: Mixed extractant, Copper, Cobalt, Nickel, Synergistic effect During separation process of copper and cobalt from nickel sulphate solution, the effects of constitutions and compositions of mixed extractant D2EHPA and PC88-A or Cyanex 272, has been studied. In one step extraction cycle, the following results are obtained:[Ni]/[Co]>4000 and [Ni]/[Cu]>40000 in nickel sulphate solution, [Co]/[Ni]>1000 and [Co]/[Cu]>30000 in cobalt chlorinate solution, [Cu]/[Ni]>10000 and [Cu]/[Co]>200 in copper sulphate solution. It was elucidated that the above-mentioned synergistic mixtures can effectively separate cobalt and copper from nickel sulphate acid solution and achieve a greater synergistic effect.

Jan 1, 2005

By Mayworm Luiz, Mantovanelli Mauro, Merisio Everaldo, Oliveira Edgar Adrian, Vieira Estéfano Aparecido, Kaneda Kazuyuki

Os filtros da estação de tratamento de água do circuito spray da planta de lingotamento contínuo apresentam problemas de desempenho quanto a vazão, gerando perda de produtividade do processo de produção de placas da ArcelorMittal Tubarão. Na etapa de filtração da água de recirculação utilizada no circuito de spray, ocorre redução da vazão com o tempo de operação não atendo a necessidade do processo. Existe uma divergência de especificação de projeto uma vez que o projeto original visa tratamento de água potável e não água do sistema direto de lingotamento, uma água com alta concentração de sólidos em suspenção e óleos&graxas. Para recuperar a vazão da água filtrada, é necessário aumentar a frequência de contra lavagem, melhorando a passagem da água e limpando os leitos, porém a alta frequência de contra lavagem torna-se uma complicação para operação da ETA, não garantindo a estabilidade da operação. O objetivo deste trabalho foi identificar e propor soluções para os problemas de vazão dos filtros de forma a garantir a especificação nominal de projeto (1380 m³/h / 5 filtros) e consequente estabilidade operacional do sistema. Foram feitas avaliações em laboratório para identificar a composição ideal do leito filtrante assim como sua distribuição granulométrica, além de modificações internas do filtro e das crepinas utilizadas no sistema de contra lavagem. Após as modificações, o filtro está operando por quase um ano conforme especificação, garantindo a vazão de filtração e prolongando o tempo de contra lavagem de 6/6 horas para 15/15 horas.

Oct 1, 2019

By C. Restarick, R. G. Robins, R. M. Taylor, I. Ennis

Lime addition to acid mine drainage waters (AMD), possibly accompanied by aeration, has been the basis for their remediation by precipitation of predominantly metal hydroxides. An efficient novel alternative technique causes precipitation of double M(II)-M(III) hydroxy sulfates which readily precipitate and are easily dewatered. When the Fe(II)/Fe(III) + Al(III) ratio of the AMD is appropriate, the Green Precipitate (GP) Process provides a more effective alternative to normal liming/aeration. The process can be adapted to give a continuous in-line treatment by the choice of suitable computer-controlled reactors designed to improve the liming efficiency, reduce scaling and control the rate of treatment. The processes are described in terms of the chemistry involved.

Jan 1, 2000

By John G. Kelly

"In 1982 an extensive study was carried out to determine the best means of size reduction for the ore to be hoisted through the borehole hoisting system at Sherritt Gordon's Fox Mine.The study examined three alternatives:1. a jaw crusher,2. pneumatic rockbreaker(s) at a grizzly, and3. hydraulic rockbreaker(s) at a grizzly.The final decision was a compromise between alternatives 2 and 3. Two rockbreakers, one pneumatic and one hydraulic, were installed over a single grizzly. Some modifications have been made to the system, but over-all it has operated at acceptable levels since its installation in July 1983.As all the ore passes through a jaw crusher before being hoisted to surface, an evaluation of the relative performance and cost-effectiveness of the jaw crusher and the two types of rockbreakers is possible. This paper outlines the initial study, and compares the three breaking systems in operation at Fox Mine.IntroductionThe Fox Mine of Sherritt Gordon Mines Ltd. is located 800 kilometres north of Winnipeg near Lynn Lake in Northern Manitoba. Production at the copper-zinc orebody began in 1970 at a rate of 3,000 tons per day. Over 12.5 million tons will have been hoisted from the underground mine when the ore reserves are depleted in October 1985.The mining method at Fox Mine is sub-level open stoping with delayed backfilling are from the upper level stopes, above the 2000 level, is mucked on the main levels established at 400-ft elevation intervals, and is fed through a central orepass to the crusher located on 2100 level. Production in the lower levels commenced in 1975, and ore from the 2200 and 2400 level stopes was hauled up a 15010 ramp by 26-ton trucks to the 2000 level orepass dump. Projected production rates from the 2600 and 2800 levels using the trucking system were too low, and therefore, in 1983 a borehole hoisting system was commissioned to hoist that ore'!'. One thousand tons per day of ore are skipped through an 8-ft diameter borehole from the 2650 level loading pocket and dumped on the 2000 level. The ore is transferred by LHD to the main orepass for crushing before being conveyed to the main shaft for hoisting to surface (Fig. 1)."

Jan 1, 1986

This report is in fulfillment of Contract H0230031 awarded to Bituminous Coal Research, Inc., on May 23, 1973. The scope of work to be performed under this contract was divided into four phases: Phase I - Design, Phase II - Construction, Phase III - Field Demonstration, and Phase IV - Analysis and Final Report. During Phase I, an agreement was finalized with the Rochester and Pittsburgh Coal Co. for conducting field tests of the proposed shearer spray systems on a longwall panel in the company's Jane Mine in Indiana County, Pa. A drum was then designed which could be used on the Eickhoff shearer, Model EW170-L, being used on this longwall and which would utilize the following spray systems: 1. One spray nozzle located in front of each cutter bit with the jet directed at the cutting surface. 2. One spray nozzle located in back of each cutter bit with the jet directed at the back of the bit. 3. Standard Eickhoff nozzles located in a header along the drum scrolls. 4. A fixed header mounted on the shearer directly behind the drum to simulate the spray system originally used on the Eickhoff shearer.

Jan 1, 1976

By Chas. F. Jackson

The work of the Mining Division is divided among seven sections, each in charge of a supervising engineer, as follows: 1. Metal-mining methods section, the supervising engineer of which is also supervising engineer of the Southwest Experiment Station at Tucson, Ariz. 2. Metal-mining research section. 3. Nonmetal-mining section. 4. Coal-mining section. 5. Mine-ventilation section. 6. Mineral-industries survey section. 7. Electrical section. The names of the sections indicate broadly the fields covered by each, and in the following, pages the objectives and type of work of each section will be summarized briefly and their active problems listed. The work clone during the fiscal year 1937 will also be summarized.

Jan 1, 1937

Jan 1, 1968