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By W. M. Corse

AT THE TURN of the century the nonferrous alloy industry was awakening to the value of scientific metallurgy, and brass foundries and rolling mills began to establish their own research laboratories for scientific research and control. As the industry grew and its scope broadened it became apparent that an organization was needed that would stand in the same relation to the nonferrous industry as the American Foundrymen's Association did to the iron foundry business. The brass founders' group of the foundrymen's association discussed the matter and it was finally decided to appoint a com- mittee to draw up a constitution for a new organization to be known as the American Brass Founders' Association. Charles J. Caley was chairman and Dr. Richard Moldenke secretary of this committee. The object of the organization as defined by the constitution was the study of the technological development of alloying and founding non- ferrous metals, and furthering the advance of nonferrous metallurgy and the standardization of materials and operations in cooperation with the Bureau of Standards and engineering societies.

Jan 1, 1932

By A. Cecala, J. Noll, J. Hummer

The National Institute for Occupational Safety and Health has observed that many control rooms and operator compartments in the U.S. mining industry do not have filtration systems capable of maintaining low dust concentrations in these areas. In this study at a mineral processing plant, to reduce respirable dust concentrations in a control room that had no cleaning system for intake air, a filtration and pressurization system originally designed for enclosed cabs was modified and installed. This system was composed of two filtering units: one to filter outside air and one to filter and recirculate the air inside the control room. Eighty-seven percent of submicrometer particles were reduced by the system under static conditions. This means that greater than 87 percent of respirable dust particles should be reduced as the particle-size distribution of respirable dust particles is greater than that of submicrometer particles, and filtration systems usually are more efficient in capturing the larger particles. A positive pressure near 0.02 inches of water gauge was produced, which is an important component of an effective system and minimizes the entry of particles, such as dust, into the room. The intake airflow was around 118 cfm, greater than the airflow suggested by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) for acceptable indoor air quality. After one year, the loading of the filter caused the airflow to decrease to 80 cfm, which still produces acceptable indoor air quality. Due to the loading of the filters, the reduction efficiency for submicrometer particles under static conditions increased to 94 percent from 87 percent.

Jan 1, 2015

By A. Cecala, J. Noll, J. Hummer

"NIOSH has observed that many control rooms and operator compartments in the US mining industry do not have filtration systems capable of maintaining low dust concentrations in these areas. In this study at a mineral processing plant, to reduce respirable dust concentrations in a control room which had no cleaning system for intake air, a filtration/pressurization system originally designed for enclosed cabs was modified and installed. Eighty-seven percent of submicron particles were reduced by the system at static conditions, meaning that greater than eighty-seven percent of respirable dust particles should be reduced. The particle size distribution for respirable dust particles are greater than for submicron particles, and filtration systems usually are more efficient in capturing the larger particles. A positive pressure near 0.02 inches of water gauge was produced which is an important component for an effective system and minimizes particles (e.g. dust) from entering into the room. The intake airflow was around 118 cfm, which is greater than the airflow suggested by ASHRAE for acceptable indoor air quality. INTRODUCTION Chronic overexposure to respirable silica dust (particle diameter < 10 microns) leads to a progressive lung disease known as silicosis. Workers who develop silicosis have an increased incidence of lung cancer and pulmonary disorders. In June 1997, the International Agency for Research on Cancer (1) found sufficient evidence to declare that inhaled crystalline silica in the form of quartz and cristobalite is carcinogenic. Mining is one of the leading industries for occupational exposure to silica dust (2-7). Control rooms located in dusty areas in some mines are of particular concern (8). Many mineral processing operations utilize operator’s compartments and/or control rooms to house workers who are performing particular job functions. Most industrial processing mills have rooms where a worker looks out over the facility and has direct control over the product flow throughout the entire building. In addition, primary crusher operators are often located in a compartment from which they are able to view the primary crushing function. Their job is to control when trucks dump into the primary jaw crusher and the rate of feed of the ore from the hopper into the crusher. Many of these control rooms and operator booths do not have filtration systems capable of cleaning air entering the control room or booth, which can result in elevated concentrations of dust in the room or booth. To reduce the dust concentrations in these rooms, it would make sense to clean the entering air with filtration/pressurization units similar to those proven to provide a clean environment in enclosed cabs."

Jan 1, 2016

The problems confronting the development of Latin America&apos;s mineral resources have hinged largely on the political and economic climates-in short, the investment climate--existing and often changing in each nation. .The attractions and risks confronting today&apos;s investors in such mineral developments have been described and debated to considerable length during the past two decades, the arguments pro and con colored by the previous experiences incurred by the would-be investor, whether company or individual. In an effort to shed light on the investment climates existing today throughout Central and South America, the Council of Economics brought four experts together at the AIME Annual Meeting last March to give their views on this subject.

Jan 7, 1966

By A. I. Collins, D. Danninger

Newmont has installed advanced control and online optimization on the dry grinding circuit and both roasters on its Carlin Trend refractory ore treatment plant. Subsequently, Newmont has developed a master plan for institutionalizing advanced control and optimization on all its processing units. Newmont is committed to a program of applying advanced control and optimization from crushing of ore to pouring of gold. This paper describes Newmont&apos;s experience with implementing advanced control and optimization and the benefits received. In addition, identification of advanced control and optimization opportunities and their economic justification is discussed.

Jan 1, 2005

"The Code was developed in 2004 through the Collaboration Agreement between Institution of Mining Engineers of Chile (IIMCh) and the Ministry of Mining (Chile) in Dec 2002. It is an amalgamation of current practices with respect to standards and procedures for exploration prospects, mineral resources, and reserves for the purpose of public reporting. Certification is required to prepare and issue information on mineral assets according to the guidelines that regulate the technical, economic, and environmental aspects that satisfy the conditions set by the Chilean capital and financial markets.The Mineral Resources Committee of the Instititution of Mining Engineers of Chile (IIMCh) is pleased to introduce theCode for the Certification of Exploration Prospects, Mineral Resources and Reserves which is the result of a Collaboration Agreement between the IIMCh and the Ministry of Mining established in December, 2002.This code synthetizes the present practice of the mining industry in regard to standards and procedures applied to exploration prospects, mineral resources, and reserves with the purpose of reporting publicly on financial instruments based on these mine assets in the capital markets. These standards follow general criteria already adopted and applied by capital markets in those countries characterized by a very dynamic and well developed mining sector such as Australia, Canada, Southafrica, United Kingdom, and others. The work done by the Mineral Resources Committee of the IIMCh has had the recognition of the Combined Reserves International Reporting Standards Committee (CRIRSCO) that leads the establishement of an international code in these matters. CRIRISCO is an entity formed by representatives of the countries previously mentioned, a representative of the Society of Mining Engineers of the UStates and a representative of the IIMCh. The Institution thanks the Ministry of Mining, the representatives of these Ministry in the Mineral Resources Committee, and specially the Minister of Mining, Sr. Alfonso Dulanto Rencoret due to the genuine support given to the IIMCh in the preparation of this Code.The Institution also thanks the Superintendencia de Valores y Seguros (SVS) because of the help given continuously to the Committee as well as by the interchange of opinions and suggestions received during the preparation of this document."

Jan 1, 2003

By E. T. W. Bailey

A HISTOR Y of the development and application of instruments, from the simplest U gauge to a modern indicating recording controller, would contain many interesting accounts of difficulties experienced and over-come. Important as is the history of development to any branch of science, this phase will, of necessity, have to be omitted from this paper and remarks confined to the results from the use of instruments in their present form. The steel industry bas, in the past decade, become increasingly instrument minded. More than ever, economy and adherence to doser specifications are demanded, and any tool that will aid in attaining these objectives by intelligent application and use finds a ready acceptance. The open-hearth furnace bas offered a field for instruments which is different from almost any other and one in which even a small percentage saved in operating costs may represent a considerable sum. Nevertheless, this department of the steel industry has been more cautions than most others in accepting the benefits which automatic control bas given on many other types of industrial furnaces, and one is puzzled why open hearths have not more generally benefited by the application of controlling instruments. The furnace operator bas to adjust the same three main valves that control fuel, combustion air, and stack draft as on most other furnaces, with the additional regulation of reversing the furnace. He is just as aware of the importance of proper draft control and correct air volume to burn most economically the applied fuel as any good boiler-plant engineer. What, then, are the special conditions that pertain to the open-hearth furnace?

Jan 1, 1939

By J. Scrimgeour

"The word ""instrumentation"" has expanded from its original meaning, which in engineering perhaps referred to measuring apparatus alone. In its broadest form, it now includes sensors, display instrumentation, standard pack-aged controllers and, most recently, the use of stored program computers for on-line process control. The paper traces the evolution, in tutorial form, of the successive application of mechanization, measurement instrumentation, automatic control, central operating systems, programmed control, process computer control, direct digital control and, finally, hierarchies of computers used for process control and corporate management as a fully integrated business system. In the field of industrial minerals, the cement industry has seen the most widespread acceptance of these techniques. Computer control has been accepted as the way of life for the blending of chemical materials and for on-line control of the cement kiln. Accordingly, the cement application is selected for further presentation in the paper. This illustrates the trend progressing from control of single loops on process variables toward the objective of total control of the product quality. The economic justification for instrumentation, centralized control, automatic control and computer control is .discussed with reference to savings in fuel, maintenance, operating labour, depreciation, power and product quality improvements."

Jan 1, 1967

By M. F. Corcoran

Rapid advances have been made in the past few years in the application of automatic controls and instrumentation to iron ore pelletizing plants. Present practice in applying instrumentation and control to the Grate-Kiln system of iron ore pelletizing is described. Major control points and loops are tabulated. Future trends in the application of digital control including computer data logging systems are described.

Jan 1, 1965

By Kenneth L. Rubow, Virgil A. Marple

"INTRODUCTION Respirable dust is defined as the dust which penetrates to the alveolated regions of the lungs. Due to the size selective nature of the particle removal mechanisms in the nasal passages and lung airways, criteria defining respirable particles must be a function of the particle size. Three criteria defining respirable particle penetration are shown in Figure 1. These criteria have been defined by the British Medical Research Council (BMRC), the American Conference of Governmental Industrial Hygienists (ACGIH) and German TBF 50-11 (1).The quantity of respirable particles in an aerosol can be measured by use of two-stage samplers. The first stage consists of a particle preclassifier with penetration characteristics corresponding to one of the respirable penetration curves in Figure 1. The large nonrespirable dust particles are removed from the airstream in the preclassifier and the smaller respirable dust particles pass on to some device which can measure their concentration (the respirable dust concentration).Instrumentation for the measurement of respirable coal mine dust has been limited by the severe conditions existing within the coal mine. The conditions of particular importance are the methane atmosphere, high humidity, and the general non-laboratory type environment. The most severe of these conditions is the methane atmosphere since any electronic or electric powered instrumentation must be intrinsically safe to operate in such an atmosphere.In spite of the difficulty of sampling respirable dust within the mines, many instruments have been developed for in mine use. Although these instruments operate under a variety of principles they generally fall within two categories: personal samplers and area samplers.A personal sampler is worn by the mines while he is performing his duties in the mine. These devices are generally small, light weight and require little power so as not to interfere with the miner's ability to work."

Jan 1, 1988

By Thomas B. Douglas

INSTRUMENTATION in the process industries can no longer be regarded as a convenience, but rather an absolute necessity. Although many chemical processes must already be conducted with instruments, every properly designed application of automatic process control will improve operation: 1) the product will be more uniform and of higher quality; 2) the manual labor saved will reduce cost; 3) uniformity of flow and uniform control of process will increase production; and 4) surges will be eliminated, making it possible to operate equipment near ultimate capacity at all times. Industrial instruments fall into two general classifications-those that measure and those that measure and control. The cement industry has been using instruments for a number of years, particularly in the burning process, primarily for indicating and recording. Automatic process control makes additional use of these instruments, and others, to control variables. Assisted by the instrument manufacturers, engineers at Ideal Cement CO. achieved considerable progress in determining how well the usual recording instruments could be made to control various phases of cement-making. The results of these experiments were used to make the new plant at Houston as wholly automatic as possible.

Jan 2, 1958

By W. A. Gow, H. H. McGreedy

It is believed that many of the problems encountered in the operation of gold cyanidation plants are difficult to resolve due to the lack of sufficient and reliable in-formation regarding the variations and actual values of operating variables at any given time. The application of instruments to monitor the more important variables in the cyanidation process should result in more efficient plant operation and a better understanding of the process. The use of pH and conductivity sensing devices for alkalinity measurements, a monitor to determine the dissolved oxygen content of plant solutions, a continuous cyanide titrator and sonic control of grinding circuits are discussed. Although the discussion is oriented toward the cyanide process, much of the paper is applicable to other ore treatment operations.

Jan 1, 1966

By Kenneth K. Humphreys

INTRODUCTION What is automation? Why automate? Webster&apos;s New Collegiate Dictionary defines automation as "the automatically controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human organs of observation, effort, and decision." This definition gives an implied answer to the second question, "Why automate?" Automation, automatic control devices, and process control equipment receive their justification in supplementing or replacing manpower, which results in decreased operating costs. In the past, processes were operated with the minimum amount of instruments needed merely to guide operators. Processes were manually con- trolled by the operator on the basis of simple temperature, pressure, flow, and level indications on a panel. Today the tendency is to design a new plant to operate in a fully automatic manner according to a preset pro- gram utilizing a minimum of manpower. In addition to this direct cost reduction in manual labor, increased equipment capacity results from uniformity of flow and uniform control of process variables. This control eliminates or minimizes surges and permits equipment to be operated at or near its ultimate capacity and, for a given material throughput, permits the use of smaller process equipment. Automatic control, therefore, be it in the field of coal processing or in any industrial field, is simply a problem of economics. Control equipment is justified in terms of its contribution toward increasing productivity, increasing profit margins, or producing a new and salable product at a profit. Instruments and control devices can be divided into two general groups: (1) units which measure and (2) units which both measure and control a process variable.

Jan 1, 1979

By S. Martins

The aim of this work is to compare three different results of charge motion in a modified 5ft diameter lab mill and to identify differences and similarities in these results. The lab mill is modified from tumbling a ball charge to tumbling a charge of disks. This modification replicates 2D motion. This 2D condition is measured using an instrumented disk (iDisk) and analysed using a video imaging system. The iDisk is equipped with a 3D accelerometer array and rotation rate sensors. With the help of a video system, some measured quantities are also determined externally. The results of these three predictions or measurements are presented. A discussion is included.

Jan 1, 2014

By Donna Kliche, Charles Kliche

It has been previously documented that various weather conditions such as wind direction and speed, cloud cover and, especially, temperature inversions can significantly affect the overpressure generated by a blast event (Siskind et al, 1980; Oriard, 1999; Siskind, 2000). The overpressure can be magnified downwind and reduced upwind; a change in the regular profile of temperature with elevation can magnify or focus the sound intensity at some distance from the blast event.

Jan 1, 2011

By R. S. Bradley

WHAT are known as insulating firebrick are lightweight firebrick with low thermal conductivity designed primarily for use in direct contact with furnace gases. These are a recent development in the refractories industry, and are really an outgrowth of the type of insulating brick suitable for use behind refractory walls developed by the insulation manufacturers. To differentiate between these two types of brick, the manufacturers have recently agreed upon the use of the term "Insulating Firebrick" to apply to the type of brick suited for use in direct contact with furnace gases, and the term "Insulating Brick" for the type suitable for use behind refractory walls. Insulation was applied to steam pipes as far back as 1900. This was a low-temperature insulation, the most common type being magnesia blocks. The next development was applying insulation to the outside of furnace walls, a service which necessitated an insulating material of higher temperature resistance. Natural diatomaceous earth, both in the powdered and brick form, was used; this was efficient and is still used extensively for backing up refractory walls where the inner surface temperature of the insulation does not exceed 1600° F.

Jan 1, 1937

By Raymond J. Kujawa

For general purposes, insulating materials may be any of those mineral substances that provide a barrier between a desired human environmental feature and an unwanted condition. In this sense, radiation shields, electrical insulations, cryogenic insulation, and acoustical barriers would qualify. For this chapter only the thermal and acoustic insulations used for the median range of normal comfort control will be covered. Because of their magnitude and complexity the other fields are left to other chapters. In another sense, this section deals only with the ultra-lightweight aggregates and insulations, rather than the multitude of light-weight structural materials. Definitions and Uses The insulating materials covered in this chapter are the three groups of mineral products that provide thermal or acoustic barriers through the median temperatures encountered in home and industry. The three mineral categories are perlite, vermiculite, and the silicate wools whether they be categorized as glass, mineral, or rock. Perlites are those amorphous aluminum silicates with minor impurities that take the form of a felsitic, glassy lava possessing a pearl-like luster and concentric cracking. In a more commercial sense the term is used to describe either the natural or processed acidic, volcanic glass, containing from 2 to 5% combined water, that may be converted to a frothy mass by heating rapidly to the softening point. Vermiculites are micaceous, hydrated magnesium iron aluminum sheet silicates of varying composition. Commercial vermiculites are any of these sheet silicates that are capable of sufficient expansion on rapid heating to make an acceptable, highly porous product. Mineral wools, rock wools, silicate cottons, glass fiber are generic names for manufactured fibers in which the fiber forming substance may be slag, certain rocks, or glass. The fibers may be made by a blowing or spinning process. The resultant fibers may be felted or matted or gathered in the manner best suited to the use. The three groups may be used competitively to insulate ceilings and walls. The fibers have strong advantages in this area as they may be manufactured in batts that are stable in residential wall construction. The perlites and vermiculites are more suited to insulate cores and cavities of masonry walls and as plaster and concrete aggregates for thermal insulations. Vermiculite is widely used for insulating attic floors. Because of manufacturing techniques and controls, the glass fibers have made great strides as composites in the plastics industry but only a few of these uses classify in the insulation category.

Jan 1, 1975

By L. Bos

The availability and reliability of large grinding mills and their Gearless Mill Drives (GMDs) are of paramount importance for the grinding process. Although GMDs have been in service for decades, and are known for their operational efficiency (reliability and robustness with reduced operating cost per ton), compared to conventional drives, in the last decade due to certain reasons some failures led to serious unscheduled shutdowns and significant insurance events. The majority of these notable "insured" failures have happened on GMDs installed on relatively large mills, as the financial impact of a failure is proportional to the through-put of the mill. Despite the occurrences of these events, as mining operations are driven by lower ore grades and the ability to continue reducing operating costs per ton, the trend for having larger mills is still very present and there is no reason why this trend should not continue. It is obvious that if not handled correctly, the possibility of large value GMD loss events, coupled with the continuing increase in mill size or required availability and reliability targets, could potentially lead to major conflicts as it becomes difficult for the insurance companies to judge the risk and hence may result in hesitation to insure these grinding circuits. This paper will not only describe the conflicting situation from both an insurer&apos;s perspective and from an equipment supplier&apos;s perspective, but also how these conflicting challenges can be successfully mastered. It has to be noted that not only the mining companies themselves, but also their insurance companies and the involved equipment suppliers have a common interest: to reach the highest availability and reliability in order to avoid or at least minimize unscheduled shut down times, and most importantly prevent unplanned events that result in extended production stoppages or reductions in through-put of GMD driven mills. From the very beginning onwards, the complete service concept together with emergency plans must be integrated on every level in the design of the grinding circuit. This approach must be implemented continuously and without compromises by all involved parties during all following stages, such as basic design, detail design, manufacturing, quality inspection and testing, packing, transportation, storage, installation, commissioning, operation and maintenance. The concept of formal risk analysis related to mill operations, maintenance and spare parts strategies must be an integral part of mining companies? decisions related to the selection for installation and continued use of large mills powered by GMDs. The service concept in place for operating mills shall also have a clear focus on very early detection of any abnormalities, so that the risk can be mitigated and unscheduled shutdown times avoided. However, if a major failure occurs, then procedures and tools shall already be available in order to ensure that production impact is minimized.

Jan 1, 2012

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

By D L. Richardson, B Tiedt, C D. Morgan

Following residentsÆ concerns that the ongoing operations of Collinsville Coal (CCP) mine may be resulting in the release of contaminants, including products of acid mine drainage (AMD), into downstream environments, the Queensland Environmental Protection Agency (QEPA) issued CCP with a Notice to Conduct or Commission an Environmental Evaluation at Three Mile Creek. A key objective of the Environmental Evaluation was to assess the extent and magnitude of impacts to aquatic communities and their habitats. A multidisciplinary investigation examined a suite of physical, chemical and biological indicators to meet this objective. The study also aimed to identify contaminants of concern and the location of potential pollutant sources. Potential indicators of AMD, including elevated dissolved solids concentrations and low pH, were evident within the mine lease. However, significant differences in concentration of these indicators upstream and downstream of the confluence with Three Mile Creek were not observed. Although only proxy indicators of AMD contamination, these results suggest that the extent of impacts downstream is minimal. For the purpose of this study, physio-chemical indicators were selected on the basis of those best likely to provide an understanding of the likelihood of contamination, within the constraints of readily available long-term monitoring data. Ecosystem health indicators were adopted to supplement the existing data set and provide a more æroundedÆ perspective of water quality attributes within the system, generally unattainable by standard physio-chemical assessments. In contrast to AMD products, sediments were considered more likely to have a widespread impact on aquatic ecosystems. Waterways throughout the study region, including those unaffected by mining, have been affected by broad-scale sedimentation and were typically highly turbid. Due to the many diffuse sources of sediment potentially liberated within the catchment, the contribution of the mine compared to other land uses on total sediment loads entering streams is difficult to determine. This is clearly a major management issue for mines throughout the Bowen Basin. Streams of the central Queensland region display enormous variability in water flows and physio-chemical characteristics over a range of spatial and temporal scales. This variability presents major difficulties in distinguishing anthropogenic impacts from natural variability (noise). Despite this variability, impact monitoring by mines in the central Queensland district has tended to focus almost entirely upon physio-chemical indicators. The results of the present study indicate that a multiple indicator approach to environmental assessment is more useful for separating mine related impacts from natural ænoiseÆ and impacts from other land uses. In the absence of such information, by adopting the precautionary principle of Ecologically Sustainable Development (ESD), there is potential for an environmental impact to be incorrectly attributed to mining when other activities in the catchment may be contributing to changes in stream æhealthÆ.

Jan 1, 2003