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By H. McSorley

"I note that many of you are involved in the production of zinc, lead and copper concentrates and metal, which I am the most familiar with among the non-ferrous metals. This afternoon, I will describe briefly the responsibilities of a commercial manager within a mining/metallurgical company, the basic framework of a non-ferrous metals concentrate agreement and lastly, a brief discussion of the copper, zinc and lead concentrate and metal markets.I hope this talk will contribute to a better understanding of the business between all of us and look forward to a discussion after the presentation.First of all, I work for Noranda Sales, which is the marketing and sales agent for Noranda Minerals' three operating units: Noranda Copper, Noranda Zinc and Mining Corporation. In addition, Noranda Sales acts for other mining companies in the marketing of their raw materials and metals. Noranda Sales is responsible for procuring all raw materials for Noranda's metallurgical plants, such as the Copper Group's Forne and Gaspe smelters, as well as the sale of surplus concentrates and by-products and metal products. In addition, Noranda Sales trades metals and concentrates and owns a metal brokerage business, Rudolf Wolff, a founding member of the London Metal Exchange. It does $3 billion of business in 60 countries, exporting some 80% of Noranda Minerals' output to the world.What are the responsibilities of commercial management in resource marketing to the mine and metal producers?Resource marketing and commercial administration involves assistance in establishing exploration priorities, contributing to feasibility studies, pre-production planning, product promotion and realization of income for many properties and metallurgical plants through completion of supply and sale agreements with other companie"

Jan 1, 1988

By Hee-suk Yun, Dae-jin Hwang, Jeong-woo Seok, Myoung-mo Kim

"In this paper, the accuracy of the data measured by a newly developed displacement measuring system, DPRMs (Digital Pile Penetration and Rebound Monitoring system) and its applicability as a quality control tool were verified by field measurements of pile penetration and rebound for pile driving performed at 3 construction sites and 1 test site. The DPRMs data were found to be much better than handwork data. A new dynamic formula for pile capacities is proposed uses the results of a pilot dynamic load test and the final pile penetration. The ratios of pile capacities obtained by the new formula to those by the dynamic load test were 94%±7.4% in the contrast with 123±28.3% by the 5S formula and 68±24.0% by Hiley's formula. This result shows the superiority of the new formula. The ratios of the maximum compressive stresses calculated by using DPRMs to those calculated by using PDA (Pile Driving Analyzer) were about 90-110±10%. This result confirms the applicability of DPRMs as an overdriving monitoring tool. Two sets of DPRMs were used to measure the 3-D displacement behavior of a pile head at the test site. The more the pile head moves laterally, the less the final set values were expected because of the loss of driving energy, but this trend was not obvious within the limited data obtained at the test site.INTRODUCTIONPile construction monitoring consists of two parts. In the first part, enough capacity of the pile is secured to stand the design load. In the other part, pile damage during driving is prevented. Although several methods can be applied to achieve the first part, PDA is nearly the only tool for measuring pile stress.Several methods such as a static load test, a dynamic load test, an Osterberg cell, and numerous driving equations can determine the pile capacity. Among them, the static load test and the dynamic load test are most widely used. The static load test is advantageous because it has the highest reliability. The disadvantages are as follows: it is costly and time-consuming. Also, the capacity of the pile under construction cannot be evaluated. The dynamic load test has lower reliability than the static load test, but it is cheaper than the static load test, is reliable enough to determine the pile capacity, can evaluate the capacity of a pile during construction, and can offer information about construction conditions such as the pile integrity and the pi le stress during driving. The dynamic load test takes a relatively short time and is low cost compared with the static load test. However, it is still costly, time-consuming, and unnecessary to apply to all piles in the field as a construction measurement tool. Therefore, driving resistance (blowcounts) is commonly measured to confirm the pile capacity at construction sites."

Jan 1, 2005

By F. T. Cawood

The distinction between real estate ownership and that of interests in the property is fundamental to the appraisal of mineral properties. This distinction affects the nature and understanding of security of tenure and, consequently, the perception of what constitutes fair value. Legal matters are a particular concern because of their influence on security of tenure, ownership definition and use restrictions. The dynamics of the market and the complex interrelationships between the factors of production define value at a specific point in time for the bundle of rights, interests and assets that constitute a mineral property. Because each mineral property is unique, physically immobile and of a wasting nature, its usefulness to its owner and society must be optimized. The US Appraisal Institute (2001) classified the forces that affect land use as the cultural, political and economic attitudes of society. These forces culminate in laws that often dictate the purposes for doing appraisals. Once the legal definition of the asset is understood, valuers can decide on the valuation process that will support the final valuation approach.

Jan 1, 2004

By J. W. Thompson

ORES PROCESS OF ORE CONCENTRATION-PATENTABILITY. The patent issued to Sulman, Pickard, and Ballot, November 6, 1905, and assigned to Minerals Separation and Minerals Separation American Syndicate, for new and useful improvements in ore concen- tration, its object being to separate metalliferous matter from gangue by means of oils and fatty acids that have a preferential affinity for such metalliferous matter, the principal feature of which is "agitat- ing the mixture to cause the oil-coated mineral to form a froth," was clearly anticipated by other patents, and each step in the process described in the Sulman, Pickard, and Ballot patent is fully described in more than one of the prior patents, with the single exception of the reduced quantity of oil used; but the discovery that the small fraction of oil is sufficient to produce flotation of the metalliferous matter can not be made by itself or in combination, the subject of a patent. Hyde v. Minerals Separation, 214 Fed., 100, p. 109, May, 1914. ACTION FOR CONVERSION OF MINERALS. In an action by the grantor of a certain mine and mining property against his grantee to recover damages for the conversion of a quantity of ore that the grantor before the conveyance had mined and extracted from the mine and placed on the dump near the mine, the plaintiff is not entitled to recover where it appears that at the time the ore was placed on the dump the mine was owned and operated by a mining company and that at the time the ore was taken out of the mine the company had no intention of doing anything with it but simply deposited it on the dump as waste and to give an opportunity to develop the mine and get better ore to send to the smelter, and that

Jan 1, 1915

By Cary Hirner, David Stacey, William A. Rochford

Design considerations and construction techniques were implemented to address groundwater infiltration from a confined aquifer during the excavation and lining of the Cady Marsh Flood Relief Tunnel. This 3-m finished diameter, 2-km long tunnel was successfully completed cost-effectively in an urban setting near East Chicago, Indiana. The soft ground was mined using a conventional tunnel boring machine with hydraulically actuated flood doors and supported with steel ribs and timber lagging. The tunnel was lined with cast-in-place concrete. Dewatering was implemented in settlement prone, boulder-laden ground in residential neighborhoods during construction to depressurize and partially dewater the aquifer at the tunnel horizon. This paper describes the design decisions and construction methods utilized to mitigate and limit infiltration into the tunnel during construction and operation, as well as manage ground settlement.

Jan 1, 2007

By James Parkes

"The proposed Baltimore Red Line light rail system includes a 3.4 mile downtown tunnel (DTT) with five underground stations. The design of the underground stations involved overcoming several challenges, including limited right-of-way, high groundwater and uplift pressures, and metamorphic rock within the station depths. An innovative design was developed to maximize the internal station space while minimizing cost. The station designs use slurry walls for temporary and permanent support and groundwater control. Depths within rock are supported with cast-in-place concrete walls, the thickness of which are minimized through the use of permanent rock anchors for support of the rock mass and slurry wall toes. Permanent tiedown anchors are used for uplift resistance, which minimizes the station depths, volume of rock excavation, and the volume of deadweight concrete. Design considerations regarding individual elements and overall integration of the slurry walls, CIP walls, and multiple anchor types are presented.INTRODUCTION The Baltimore Red Line (BRL) project is a proposed light rail transit line for the Maryland Transit Administration (MTA) that runs east to west through Baltimore City and County. The project includes the Downtown Tunnel (DTT) consisting of 3.0 miles of twin running tunnels, two portals, five underground stations, and a pedestrian tunnel, as shown in Figure 1. The tunnels have an outside diameter of 21.8 feet and are designed to be mined using pressurized face tunnel boring machines (TBMs). The stations, portals, and the pedestrian tunnel are designed as cut-and-cover structures using slurry walls (concrete diaphragm walls) for both temporary support of excavation (SOE) and permanent structural walls. The dimensions of the five underground stations are summarized in Table 1. Design challenges included limited right-of-way (ROW), challenging soils conditions, strong metamorphic rock within the station depths, and high groundwater conditions. The final station designs included innovative use of slurry walls, tieback anchors, rock anchors, and tiedown anchors."

Jan 1, 2016

By M. D. Carver

This publication describes development by the Bureau of Mines of a quality evaluation procedure for certifying the adequacy of production lots of Kroll process zirconium sponge the Bureau had produced for reactor applications. After the procedure was devised, the next step was to apply it in controlling the quality of one-half million pounds of zirconium sponge com-prising 259 production lots, called blends, originating at the Metallurgy Research Center of the Bureau at Albany, Oreg. The Bureau concluded that the evaluation method developed was adequate and that by this method the zirconium blends having impurity levels or other property values outside specification limits were differentiated and thus were diverted from nuclear energy end uses. The research was performed under contract for the Bureau of Ships, Department of the Navy, and for the Atomic Energy Commission (AEC).

Jan 1, 1960

By D. Waite

The Chairman opened the session by wondering why so few papers on Maritime Structures had been received for this conference. Perhaps because the marine environment is so hostile and the access so difficult that engineers tend to be more prudent about new ideas and designs. Dennis Waite noted the number of grey hairs in the room - grey hairs which could be equated with experience gained the hard way. He hoped that this experience would be passed on in the discussion period of this session. The Chairman was delighted to welcome two authors from China, Mr Sun and Mr Liang. He was most grateful on behalf of the conference for their efforts both in preparing their papers and for being able to present them. He regretted that Messrs Noce and Fedolino were not able to present their paper and then welcomed Mr Christensen from Denmark who would present the first paper.

Jan 1, 1991

Approximately half of all the fuel energy used in the United states is now pro-vided by oil and natural gas. A persistent and rapid growth in energy demand during the last 3 decades has been absorbed largely by the liquid and gaseous rather than solid fuels. In 1948 the energy provided by coal was substantially the same as in 1920. Meanwhile, the use of oil and natural gas each had increased fivefold. On a per capita basis, the change is more significant. Coal consumption has dropped from about 6 tons per person to 4-1/2 tons, while oil has increased from 4-1/3 barrels to 14-1/3, and natural gas from 7,500 cubic feet to about 35,000. These facts would have only academic interest if the United States had unlimited supplies of all fuels. However, while the Nation's reserves of coal are adequate to meet our needs for centuries, those of oil and natural gas appear limited. It is obvious, therefore, that the security of our liquid-fuel position would be greatly enhanced if the supply could be based in an increasing degree on solid fuels, such as coal and oil shale, which make up more than 95 percent of our fuel reserves, instead of natural oil and gas. In addition, this would create new employment and help to stabilize the market for coal, which may be facing comparatively bleak prospects in the near future unless its position with respect to other fuels is improved.

Jan 1, 1950

By N. E. Hanna

As part of a program for improving, the safety of permissible explosives, the Federal Bureau of Mines has undertaken an investigation to establish the ability of sodium chloride to reduce the incendivity of permissible explosives to firedamp atmospheres. A motivating influence for this investigation has been the comparatively extensive experience of British and other European investigators, who used sodium chloride as a component of their permitted explosives (1, 5, 6 7).5/ In the United States research and development work of this type has been less extensive, although sodium chloride has been added to permissible explosives as a cooling agent (9) for many years. The results of the first phase of this investigation were presented in a previous paper (8), which established that adding up to 10 percent sodium chloride to permissible explosives reduces the likelihood of ignition of firedamp in the gallery test; however, the results were somewhat inconsistent, and the conclusions were qualified. Accordingly, the investigation was continued with a study of the effect of added sodium chloride as a function of the quantity added and of the particle size of the salt.

Jan 1, 1960

By L. A. Haas

A kinetic study of the carbon deposition reaction was undertaken by the Bureau of Mines as part of a broad investigation of metallurgical reactions in the iron ore blast furnace. The disproportionation of carbon monoxide on iron pellets was investigated at carbon monoxide pressures between 0.5 and 2 atmospheres (absolute) and temperatures from 400° to 1,075° C. Gas flow in the range from 0.25 to 0.85 standard liter per minute was found to have little effect on the reaction velocity. The addition of nitrogen and helium to caron monoxide exerted only a dilution effect on the rate of carbon deposition. However, an addition of 1 percent hydrogen increased the rate about 100 times. Small amounts of carbon dioxide in the inlet gas exerted little effect on the rate of carbon deposition. The maximum rate for carbon deposition in the first 2 hours occurred at 550° C. The apparent molar activation energies at various stages of the reaction were found to vary from 13 kcal initially to 36 kcal during the latter stages of the reaction. The reaction rate behavior was tentatively explained by an adsorption step followed by the diffusion of iron through a shell of inactive iron carbide.

Jan 1, 1968

By J Fut=

The rotary drilling of rocks is widespread technology in mining and in tunnelling. The paper describes the results of research by aim to find relationships between optimal drilling and sound signal of drilling machine. The optimisation criterion has been formulated as the minimisation of specific energy with maximal effective speed of drilling in process of the rock disintegration. The research in this field has been made on experimental drilling stand. Our monitoring system has measured following variables: the pressing force of core drill, the revolutions of drilling head, the length of drilling, the time, the power, and the acoustic signals. For measurement of acoustic signals have been used very sensitively sound meter MEDIATOR 2238. From this measurements have been processed acoustic spectrums. Then we are found relationships between optimal control of drilling and composition of acoustic spectrum. On base of experimental results, we can formulate the optimal control following: æTo achieve the minimum difference between the equivalent sound level at the load and idle modes only at the representative frequency (f = 1000 Hz)Æ. The representative frequency dependences on type of the rock New method based on these relationships enables the optimal control of drilling machine by using measured acoustic signals only.

Jan 1, 2003

By A. J. Neale, B. C. Flintoff

"In most mineral processing operations the term audit is usually reserved for the exercise of checking financial records and/ or safety practices. While these activities are time consuming, no one disputes their necessity or value. If we subject these areas to such careful scrutiny, why is it that we don't normally apply the same principles to critically examine process operation. After all, the operating efficiency of the plant impacts directly on the measures of profitability.A mineral processing plant is a complex system that has a number of distinct, but mutually dependent elements: process equipment, instrumentation, operating policies, maintenance policies, control strategies and people. To ensure maximum economic performance, in the dynamic environment that characterizes a concentrator, requires a periodic review of each of these areas. However, to be useful, the study must be based on sound metallurgical principles and be conducted in a highly focused manner. Experience teaches us that the exercise is very revealing and potentially very rewarding.This paper will discuss the process audit process and illustrate its potential value through illustration taken from plant studies.IntroductionThe last twenty years have seen tremendous technological and organizational changes sweep the minerals industry. Process control systems, on-stream analyzers, and gold recovery techniques barely conceived twenty years ago are now incorporated in virtually all new installations in an effort to maximize operating efficiencies. In conjunction with these developments, changes in the way plants are managed, down-sizing of technical staff, reduction in the size of operating crews, and the flattening out of the management structure have significantly reduced operating costs. As a result, plants are making more efficient use of our natural resources, minimizing the costs of production, and in turn maximizing operating profits. Or are they?"

Jan 1, 1991

By A. C. Fieldner

In the course of its investigations on the properties of coal and in rendering fuel-inspection service to other agencies of the Government, the Bureau of Mines has accumulated a comprehensive file of coal analyses that includes data on virtually every coal field of commercial importance in the United States. As knowledge of the composition of coal is potentially valuable to every user of coal, the Bureau publishes its analytical records. Before 1921 such publications contained analyses of coal from all parts of the United States; individual analyses or average analyses of a series of shipments of coal were given with the name and location of the mine producing the coal. Beginning in 1921 the analyses were published by separate States because the quantity of data had become so great. The separate papers published to date, with Bureau of Mines Technical Paper numbers, are as follows: Alabama, 347; Arkansas, 416; Colorado, 574; Illinois, 634 and 641; Indiana, 417; Iowa, 269; Kansas, 455; Kentucky, 30S; Maryland, 465; Missouri, 366; Montana, 529; New Mexico, 569; Ohio, 344; Oklahoma, 411 ; Pennsylvania (bituminous), 590; Tennessee, 356; Utah, 345; Virginia, 365; Washington, 491 and 618 (618, published in 1941, supplements 491); West Virginia, 405 and 626; and Wyoming, 484. From time to time the various papers will be revised to include later analyses and other data. The Bureau of Mines annually receives many inquiries as to the composition of coals obtained from specific localities or, conversely, as to the localities from which a given kind of coal may be obtained. This paper presents a summary, in tabular form, of the composition of commercial coal resources of the country. Specimen analyses are given exemplifying the analysis of coal mined in each coal-producing county, or, where it was feasible, coal from each bed in each county; also, ranges of analyses, within which the composition of most of the coal represented will fall, are given where there were enough analyses to permit satisfactory determination of the ranges. In addition, the degree of metamorphism from lignite toward anthracite of much of the coal is indicated by the classification by rank. This classification reveals to more experienced users of coal some of the general properties of coal, that is, whether the flame will be long or short, whether the coal will cake in the fire, and how it is likely to behave on exposure and in storage.

Jan 1, 1942

By William S. Alldredge

The Washington Metropolitan Area Transit Authority(WMATA) officially came into existence in February 1967 after the District of Columbia, Maryland, and Virginia joined in a com¬pact pursuant to Federal creative legislation signed the previous November to build a regional rapid rail transit system called METRO (1). The parent organization was the National Capital Transportation Agency (NCTA), a Federal agency, subject to Federal statutes and regulations. Soon after the completion of the transition from NCTA to the new "non-Federal" status of the Authority, the Board of Directors of the Authority formally adopted procurement policies and procedures (2). These are specific statements concerning competition by formal advertising for bids or by solicitation of proposals for negotiation, contracting authority, approval of awards, awards of contract modifications, and processing of claims and disputes. These policies and procedures are silent as to Federal procurement statutes and regulations. But because of the Authority's origin, the sensitive nature of the compact among the several sovereign jurisdictions, Federal financing of two-thirds of the costs, and the resultant surveillance by the General Accounting Office over staff operations, the Authority's procurement practices follow closely Federal regulations adapted to WMATA's needs. This is an important point and is the foundation of contractual relations between the Authority as the owner and its construction contractors. Various constraints and flexibilities of this arrangement with respect to excavation and tunneling contracts will be pointed out in the ensuing discussions.

Jan 1, 1974

By Knut H. Hubert

The GRATE-KILN System plant at Svappavaara, Sweden, was constructed for LKAB by Allis-Chalmers under a turnkey contract and commissioned in 1969. The plant was designed to produce iron ore pellets from magnetite concentrate at 6100 mtpd using imported fuel oil. It represented the state of the art for plants of its type at the time. Fuel rated capacity was attained within one week of start-up. Product quality, power usage, fuel consumption and machine wear were within warranty limits during sustained production thereafter. As operator skills improved and gas handling system reserve capability was utilized, the plant frequently produced acceptable product at up to 115% of design capacity. During the period 1969 to 1976, market demands increased for high-quality pellets while energy costs rose steadily. At the same time, important advances in the design of GRATE-KILN Systems were being made in other plants constructed by Allis-Chalmers.

Jan 1, 1980

By Kazuya Nakabo

In this article, influences of restraint and MgO content on densification of alumina-magnesia castable during heating were experimentally studied. High thermal expansion-alumina-magnesia castable specimens were surrounded by low thermal expansion-alumina-silica castables, and heated in an electric furnace. Doing so allows restrained heating of alumina-magnesia castable. According to the results of simple calculations, the restraint stresses were estimated to be between 2 to 20 MPa, so the experimental conditions were considered reasonable. As a result of the experiments, it was verified that restraint densifies alumina-magnesia castable, resulting in an increase in modulus of rupture and modulus of elasticity. The densification effect of restraint became larger as the MgO content increased. The effects are attributable to an in-situ spinel forming reaction, which improves corrosion resistance.Taking the temperature distribution in the castable lining into account, large restraint stress is expected for the hot face while only a little effect is expected for back end. Thus, excessive difference in material property in the thickness direction, which is undesirable in terms of structural spalling, is a concern.Hence, the MgO content of alumina-magnesia castable should be determined carefully, taking not only corrosion resistance but also spalling resistance into consideration.

Oct 30, 2017

By Afshin Sadri

One of the main reasons for blast furnace reline is the loss of refractory lining, particularly in the hearth and taphole regions. Intense operation of the blast furnace can result in extensive refractory wear and deterioration. This can then affect the continuity of the operation and the furnace campaign life. Novo-Lipetsk (NLMK) and Hatch developed a systematic approach to monitor the condition of blast furnace hearth linings using Acousto Ultrasonic-Echo (AU-E), a non-destructive testing system developed by Hatch. Continuous and periodic inspections of blast furnaces revealed areas with accelerated refractory deterioration, formation of elephant foot, extent and speed of refractory wear, as well as cracks and other anomalies. Improvement in coke quality, stave washing, the addition of titania, and other changes were recommended and implemented to prolong furnace life while maintaining the intensity of furnace operation. This paper demonstrates how the coordinated efforts between NLMK and Hatch resulted in prolonging the blast furnace campaign life.

Aug 17, 2017

By Robert B. Hoekzema

The Bureau of Mines and U.S. Geological Survey completed a 4-yr (1979-82) mineral appraisal of the Chugach National Forest (CNF), AK. This report summarizes the Bureau's placer gold studies in the CNF. Placer mining from the mid-1890's through 1982 produced an estimated 133,800 oz of gold, of which two-thirds was produced prior to 1920. As much as 6,800 oz of placer gold was produced from 1979 to 1982. Most production came from Crow, Canyon, and Resurrection Creeks. Five types of placer gold deposits were identified in the CNF: (1) alluvial placers, (2) bench placers, (3) eluvial placers, (4) glacial placers, and (5) marine placers. Placer sampling indicated a potential for gold production from alluvial and bench placers associated with historically mined drainages such as Crow, Canyon, Resurrection, Sixmile, and Mills Creeks and from unmined drainages including the Avery, Kings, Snow, Copper, and Tasnuna Rivers and several smaller streams throughout the CNF. Results of fineness tests indicated that gold from the CNF ranges from 455 to over 950 fine. Subsequent investigations in drainages with anomalous placer sample values also identified previously unknown lode mineralization.

Jan 1, 1986

By T. Urbancic, Eric von Lunen, G. Viegas, A. Baig

"The characterization of the failure process of induced fractures by hydraulic stimulation is fundamental to understanding the generation and evolution of the discrete fracture network within the reservoir. A more detailed analysis of the fracture mechanism can be a powerful tool for identifying fluid flow paths and proppant placement within the reservoir. For example, during the rupture process the energy release is partitioned into different physical processes for which the relative ratio is changed by the presence of fluids or rotations in the local stress field with relation to the frictional resistance in the fracture plane. Fractures occurring in the same host rock under the same stress conditions are expected to rupture similarly, independent of their size (self-similarity). Changes in the scaling relationships of fractures are indicative of a change in the failure process, host rock or in-situ stress. Correlation of failure process data with reservoir rock properties and the in-situ stress field will help identify regions within the reservoir with characteristic types of failures. Further correlation with hydrocarbon production data can be used to develop efficient treatment plans and production diagnostic tools.In this study we investigate the failure process of ~27,000 microseismic (M < -1) fractures induced during a hydraulic fracturing shale completion program in NE British Columbia, Canada by estimating static and dynamic source parameters, such as dynamic and static stress drop, radiated energy, seismic efficiency, moment tensor, fracture plane orientation, slip direction and rupture velocity. On average, the microseismic events have low radiated energy, low dynamic stress and low seismic efficiency, consistent with the obtained slow rupture velocities. Events fail in overshoot mode (slip weakening failure model), with fluids lubricating faults and decreasing friction resistance. Events occurring in deeper formations tend to have faster rupture velocities and are more efficient in radiating energy. Variations in rupture velocity tend to correlate with variation in depth, fault azimuth and elapsed time, reflecting a dominance of the local stress field over other factors.Further identification of spatial and temporal distribution of families of events with similar characteristic rupture behaviors, based on either rock formation, depth, source type, fracture plane orientation, stress drop, pad or proppant stage, may be used as a proxy for specific fracture network development and hydrocarbon production. This information may be used to determine reservoir properties, constrain reservoir geo-mechanical models with measured physical parameters, classify dynamic rupture processes for fracture models and improve fracture treatment designs. These will be the focus of future studies."

Jan 1, 2015