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By George H. K. Schenck

It seems appropriate to review the history of mechanization of our underground coal mines at this time when many favorable flags are flying for this industry. It is a reasonable hope that such a review may stimulate thinking as to the directions that new technological developments are apt to take and in which members of the Society of Mining Engineers are destined to play important roles. Discussion of the relative importance of the various changes that have taken place since the advent of electric power provides the starting point. It is in the economic factors utilized that we find conditions which permit more efficient utilization of the capital committed to the industry. Concepts rather than specific items are emphasized in the following discussion because once the value of a concept, such as mechanical conveyors, is established, it then spawns many variations which are not significantly different. The shift from animate to inanimate energy has been the most important change in the modern industrial scene, including coal mining. Although introduced into coal mines for some purposes early in the period of general electrification, the coal industry adopted mechanical power relatively slowly, and 1944 was the first year in which a majority of deep-mined coal was mechanically loaded.

Jan 1, 1968

By P. C. Clark

This paper is an overview of the requirements and concerns for minerals and pigments used in papermaking. The first part of this paper deals with mineral or pigment filling in the actual papermaking process. The second part deals with the pigment or mineral properties that are important in today's coating processes.

Jan 1, 1993

By J. H. Jennekens

INTRODUCTION "Most people would probably agree that some degree of government control and regulation is essential in modern society, and it will likely continue as an important part of our social organization for the foreseeable future. But most of us tend to be ambivalent about it. In one situation or another we are likely to see government commitment to social benefit programs or regulatory devices either as an expanding encroachment on the freedom of the individual or as an undue interference with private enterprise or with the rules of the market place. But even where there is agreement as to the desirability of government initiatives, either in general or in a particular context, it by no means follows that there will be approval of the mechanisms or procedures used or the means of carrying them out." The above statement is taken from a 1980 Working Paper of the Law Reform Commission of Canada prepared in connection with its study of the exercise of administrative law in Canada and the practices and procedures of administrative tribunals. The Atomic Energy Control Board (AECB) is one such administrative tribunal, and as the federal nuclear regulatory authority, it is responsible for licensing the production, possession and use of nuclear materials, equipment and facilities and enforcing compliance with licence conditions governing the health, safety, security and environmental aspects of the activities involved. Although the AECB was established 35 years ago with the passage in August 1946 of the Atomic Energy Control Act, like many administrative tribunals its role and functions and the regulatory process which it applies have evolved significantly during this period. The changes which have taken place over the years reflect not only the vast scientific and technological developments which have occurred but also the marked differences between contemporary society and the social milieu of the mid-1940s. However, the basic philosophy of nuclear regulation in Canada and the underlying principles of the regulatory process have changed very little. Certainly, the process is far more open in terms of the general public, it has become appreciably more comprehensive and systematic in terms of the depth and extent of both the pre- and post-licensing technical evaluations which are conducted and the ensuing compliance program. Furthermore, it now applies to the whole of the nuclear fuel cycle as well as the industrial, agricultural and medical applications of radionuclides. Nevertheless the following fundamental principles remain unchanged: a. primary responsibility for achieving high standards of nuclear safety and environmental protection in the design, construction, commissioning and operation of nuclear facilities resides with the licensee; b. the credibility of the nuclear regulatory process depends not only upon its technical correctness and practicability, but also upon acceptance by the public-at-large of its perceived effectiveness and efficiency; c. regulatory criteria and principles should be concise, clearly stated and understandable; d. regulatory decision-making should be based upon stated criteria and principles taking into account pertinent scientific and technical facts only; e. fairness and impartiality must characterize all regulatory decision-making; f. the regulatory process should be subject to a comprehensive periodic review and evaluation to ensure that it continues to produce the desired results at justified costs. EXPLANATORY NOTES The mere statement of a set of principles is a relatively simple task. Far more difficult is the explanation of what these principles mean in practical terms. To stipulate that a licensee bears the primary responsibility for achieving and maintaining high standards of nuclear safety and environmental protection may be regarded by some as an attempt by the regulatory agency to evade the responsibilities assigned to it. However, this is not the case. It is unrealistic for anyone to claim that a licensee only complies with accepted norms of public and occupational health and safety and of environmental protection because of the fear of prosecution. The vast majority of citizens conduct their affairs in a proper manner not because there

Jan 1, 1981

By Richard Jr. Ray, David Johnston, Phil Blankenship

Injection of inert gases to combat mine fires has been practiced in various parts of the world for a long time. Of late, nitrogen has become the preferred inert gas for control of mine fires and safe salvage of longwall equipment as compared to carbon dioxide or fuel gases produced from burning of fuel. In India, carbon dioxide has been used for fire fighting in a number of mines during the 1960s and 1970s. More recently inert gas produced from burning of fuel oil in surface plants has been used in controlling the atmosphere in fire areas in two mines. In yet other cases, liquid nitrogen has either been poured directly into fire areas in liquid form or injected in gaseous form to keep the fire in check. Nitrogen produced in liquid form in an oxygen plant is more costly than nitrogen produced from PSA (pressure swing adsorption) based plants. A PSA-based plant has been installed in one of the Indian mines in 1986 and more are in the offing. This paper reviews the application of various inert gases in Indian mines and discusses the likely trend of inert gas application in Indian mines in the future.

Jan 1, 1989

By Karan S. Keith, Haydn H. Murray

The sorptive and impervious nature of clay materials was recognized long before modem technology allowed us to understand the physiochemistry of clays. In Cyprus, around 5000 BC, sorbent clays were used for fulling woolen cloth. One of the earliest recorded uses of clays as an impervious liner was more than 3200 years ago in the construction of a bitumen-sand-gravel-clay liner built along the embankment of the Tigris River at Assur. Today one of the most common applications for clay minerals in the environmental industry is for use as impermeable barriers to fluid transport. Clay minerals are fine in particle size and thus have large surface areas, which, as a result of intermolecular forces and ionic substitutions, make them excellent materials for both ion exchange and ion sorption. Therefore it was logical to consider certain clay materials for applications in the environmental industry, where they can act as physical and chemical traps for potential contaminants. Certain bentonites have historically been used as sealants for fluids (Grim, 1962), and other clays have been used as sorbents for both water and oil (Haden, Jr., 1972). Prior to the 1980s, disposal of the nation's municipal, commercial, chemical, and nuclear wastes was largely indiscriminate and poorly regulated. This created environmental pollution problems, especially with respect to groundwater contamination. Promulgation of federal regulations like the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA - commonly known as Superfund) have forced a more careful and costly approach to waste disposal. The US Environmental Protection Agency (EPA) is the government body charged with enforcing and ensuring compliance with federal regulations governing toxic waste production, storage, and disposal. Widespread application of geotechnology to the design and construction of waste containment systems and to pollution remediation has become necessary due to such laws and because of increasing use of the subsurface environment for the disposal of hazardous wastes. In the United States nearly 1.8 kg of trash is disposed of per person per day, which amounts to nearly 181 Mt per year. This amount is more than double the waste produced in 1960, and these numbers are expected to continue to increase. Canada produces approximately 1.68 kg of waste per person per day. The EPA estimates that in the United States 64% of our garbage is landfilled, 18% recycled, and 18% incinerated. Even with continued increases in recycling and incineration efforts, the EPA projects that the United States will still need 82% of today's landfill capacity in the year 2000. Data on the exact number of landfills in the United States and Canada is conflicting in part because of changing definitions of what constitutes a landfill and because of inadequate record- keeping by some states and provinces. An estimate of the number of municipal solid waste (MSW) landfills in the United States in 1990 to 1991 ranged from 4 462 to 10 467 with an average estimate of 6 600. In Canada the number of MSW landfills reported varied from 5 493 in a 1982 survey to 1 766 reported in a 1991 National Solid Wastes Management Association (NSWMA) survey (Repa and Sheets, 1992b). A properly operated MSW landfill on average requires 1 hectare of land per year per 25 000 people (Coates, 198 1). In addition to MSW facilities, there are also waste disposal facilities needed for hazardous waste and low level and high level radioactive waste. In 1983, approximately 266 Mt of hazardous waste was generated in the United States, almost 50% of this by industrial production. About 68% of the hazardous waste generated in the United States and Canada and almost 50% generated in Europe are still landfilled (Egger, 1987). In 1985, approximately 51 000 m3 of commercially produced low level radioactive waste was disposed of in radioactive waste disposal sites across the United States (Jungling and Greeves, 1989). By 1987, the US defense program had produced approximately 10 000 t of high level nuclear waste. In addition, there were approximately 14 000 t of spent fuel assemblies from commercial nuclear power plants in temporary storage; the amount is expected to nearly triple by the year 2000. Presently most commercial spent fuel assemblies are stored in water-filled pools at nuclear power plants. Defense waste is stored on federal reservations in surface and underground steel tanks (Anon., 1987). Under federal law nearly all waste disposal and containment sites are required to have a liner or barrier and a cover system design that meets federal- or state-approved hydraulic conductivity requirements for the type of waste that the site will receive. When approved materials, necessary for constructing the waste containment structure, are not available on site, one of the most economical ways to meet these requirements is through the use of clay, soil/clay, or clay/geotextile materials. In a 1991 survey by NSWMA of its members and other select private sector facilities, 81% of the surveyed landfills had some type of liner system. About 75% of these liners were clay materials (either recompacted or natural). The remaining 30% were using flexible membrane liners as part of a liner system. Clay liner materials are most commonly used in the South, Midwest, West-central, and South-central regions of the United States. About 93% of the landfill facilities had closure plans, and of these 91 % were using clay materials in some way for the final cover material (Repa and Sheets, 1992a). Waste barriers and containment structures take several basic forms, and they are used in a variety of different applications: 1) cutoff walls, 2) soil or soil/clay-admix liners, 3) geosynthetic bentonite-clay/geotextile membranes, 4) radioactive waste containment barriers, and 5) synthetic geomembranes. This chapter will discuss the first four of these categories. The field of synthetic geomembranes, although a related topic, is beyond the scope of

Jan 1, 1994

By L. Xinguang

Shandong MinMetals Corporation, a state-owned import and export organization located in the city of Qingdao, Shandong Province, China, was opened in 1954, with the mission of marketing metal products and industrial raw material in oversea areas for hard currency to support the modernization project of the country as well as the province. The management officers are appointed by the provincial government, and report to the Foreign Trade Department of Shandong Province. Meanwhile, the company also receives guidance from MinMetals head office in Beijing, the capital city of China. The head office does not own and control any provincial MinMetals organizations, but merely coordinate business among provinces.

Jan 1, 1990

By S. Upadhyay, A. M. Afrapoli

"Fluctuation in market price of mineral products has enforced mining companies to cut down their operating costs. One useful way of reducing operating costs in mining operations is to make optimal operational decisions, incorporating efficient mining fleet management systems (FMS). Over the last 50 years, several types of FMS have been developed and introduced in the mining systems around the world. However, there are two major shortcomings in existing systems. Firstly, none of the existing systems consider effects of the short-term plan on dynamic truck assignment. Secondly, most of the existing FMSs make decisions in a way that optimize a specific objective while ignoring others. Herein, we propose a multi stage and multi objective FMS that deals with aforementioned shortcomings of the currently available systems. The developed FMS, in its upper stage, links semi-dynamic operational decision making process to the short-term production plan by simultaneously assigning shovels to mining faces and allocating trucks to the shovels by implementing its first multi objective decision making model. Then in its second stage, in a real time dynamic decision making process, it assigns trucks to shovels and corresponding destinations by optimizing its second multi objective decision making model. The developed fleet management system has been verified using an Iron ore case study and the results are presented in this paper. INTRODUCTION Open pit mining method is the most common method to mine mineral from the earth. Based on Wetherelt and van der Wielen (2011) there exist 2500 open pit metal mines that are categorized as industrial scale mines. Over all of those, the amount of material handled using truck and shovel material handling system is more than the amount handled by all other systems together (Humphrey & Wagner, 2011).It has been proven by several studies that more than 50 percent of operating cost in a truck and shovel based open pit mining operation is accounted for material handling (Moradi Afrapoli & Askari-Nasab, 2017, Alarie & Gamache, 2002, Ahangaran et al., 2012). Thus, introducing even 1 to 2 percent cut in its material handling cost saves huge amount of money for the stakeholders. Over the last 50 years, two major areas have been identified to cut this cost. On one hand mining industries have been implementing equipment with higher production capacities, and on the other hand, researchers have been developing operations research techniques to make dynamic decisions as close to optimal as possible to deduct operational costs in truck and shovel based mining operations."

Jan 1, 2018

By Keith G. Wallace

Coal mine ventilation systems are often subject to high leakage rates. As a result, changes in airflow resistance will strongly affect the efficiency with which air is delivered to the working place. One major source of airflow resistance is the line brattice used to direct air from the last open crosscut to the working face. Because it is a great distance from the fan, the resistance of the line brattice can result in more overall leakage than an equivalent resistance closer to the fan. Substituting auxiliary fans for brattice eliminates this source of resistance, with improvements in system efficiency and cost. Also, in some mines, the leakage that leads to spontaneous combustion can be reduced. The benefits obtained by several different brattice and fan substitutions have been studied by Mine Ventilation Services, Inc., under contract to the Bureau of Mines. Changes in main fan duty were compared with additional costs associated with auxiliary fans. Results indicate that in some circumstances, considerable leakage reductions and cost savings are possible.

Jan 1, 1986

By R. A. Hill

A brief explanation of the theoretical functioning of a regenerative system followed by its application to firstly, shuttlecars and then continuous miners and its effect on performance thereof with regard to handling, production and safety.

Jan 1, 1986

By E. C. Speers

The Ray Mines Division has a long and illustrious history beginning in 1911, as one of the early underground block caving copper mining operations. The tonnage mined from the beginning of operations, increased from about 8, 000 TPD in the early years to the present daily tonnage of 22, 500 tons, mined by open pit methods. The Ray basic milling practice has been relatively unchanged since 1927 when the sulphide-flotation process was introduced at Ray. The leach-precipitation-flotation process introduced in 1956 has been the only major process change. The change from underground to open pit' mining was accompanied by a renewed drilling and exploration program which developed large tonnages of low grade copper ores both in the porphyry and the diabase. The ore bodies as outlined were of such a grade and size that it soon became apparent that economical operations could not be developed with the lower tonnage rate. Also that in order to develop these newly proven ores, it would be necessary to move the Ray crushing plant, the Ray. supporting shops, offices, a substantial part of the Ray townsite, and would also involve the rerouting of Mineral Creek, a typical Arizona stream which is dry most of the year but can flow as high, as 8, 000 second feet in the rainy season. This paper describes those changes in flow sheet made necessary both by the increased tonnage .and the requirement to move as much of the crushing facilities from the Ray area as practical in order to free the mine for the extension of its physical limits.

Jan 1, 1961

By R. D. Lopez

The concept of "heat recuperation" for the grate-kiln pelletizing system was first implemented at the Sydvaranger plant in Norway in 1974. Essentially, heat recuperation involves bringing hot air from the second stage of the pellet cooler to the drying zone to increase drying-air temperature to the maximum limit. 'Burner-fuel savings result from a lower kiln secondary-air mass flow at a higher temperature. Because of the fuel benefits achieved at Sydvaranger, heat recuperation has been included innumerous new grate-kiln plants built since then, and some older plants have been retrofitted for heat recuperation. In recent years there has been much confusion about the fuel benefits of heat recuperation. To answer some of the questions, a mathematical model was developed and plant tests were conducted at Minntac Phase 111. Minntac is a magnetite taconite concentrating and pelletizing plant, and Phase III has two indurating lines. This paper presents the results of the studies and plant tests.

Jan 1, 1980

By Steven McCutcheon

As most of us have learned through prior and often frustrating experience, anyone proposing to construct a new or expanded mining-ore processing facility must first contend with a rather complex array of environmental laws and permitting regulations administered by a number of different Federal, State and local agencies. At our lost count, there were about 55 federal enactments affecting base and precious metals projects. Applicable State and local laws will usually increase that number significantly. The time and costs associated with complying with all these various regulatory programs usually constitutes one of the major areas of uncertainty in the development of a proposed project. There are many in the mining industry who firmly believe that these environmental regulation and permit programs necessarily causes significant delays and increased costs in the development of a project. This belief, unfortunately, is probably a result of a basic misunderstanding of how the environmental permitting and regulatory system actually works.

Jan 1, 1984

By Yvon H. Poirier

Carbon addition in the oxide pelletizing process is a big concern at the Sidbec-Normines pelletizing plant since 1976. Laboratory pot-grate testing carried out before the initial start-up of the Port-Cartier plant indicated that the nominal pelletizing grate capacity could be increased by fifteen percent with a suitable carbon addition. Also an improved induration cycle offered the possibility of a significant energy reduction within the process with no adverse effect on pellet quality. A one month plant scale program duplicated the lab test results and confirmed the anticipated cost saving by using these techniques. Since March '80, Sidbec-Normines use coke addition as a current operation. This paper reviews briefly earlier laboratory and in-plant test work carried out to investigate the effects of adding carbon materials to the Fire Lake hematite concentrate, and presents operation techniques and plant results of carbon addition in the Port-Cartier pellet plant.

Jan 1, 1982

By William H. Lehr

In recent years, we have witnessed many innovations in the equipment used in handling bulk materials. Not too long ago, any sizeable stockpile of coal or iron ore was attended by one or more material handling bridges. More recently, large stockpiles have been built with mobile equipment of' the earth moving type with bulldozers and front end Loaders being utilized in reclaiming operations. The most recent stocking and reclaiming device is the rotary bucket wheel machine. The early bucket wheel machines built in the United States were developed for the strip mining of coal. We understand that the first American machine was built in the Midwest in 1944. This type of unit was developed in an effort to reduce the cost of removing overburden and to provide satisfactory spoil disposal. As the available coal reserves under shallow cover were exhausted, the cost of removing the deeper overburden with conventional equipment became too great for these operations to continue profitably. The first machine has now been followed by six or seven additional units, the largest of which can handle material at a rate of more than 7000 cubic yards per hour.

Jan 1, 1965

By G. R. Tostengard

Gold plant performance during the start-up period, which extends until capacity production is sustained, has a major impact on the internal rate of return and the net present value of gold projects regardless of mining and processing configurations. The start-up period experiences substandard production, extra expenses, and sometimes reduced recovery. This results in lost profits, a portion of which are recouped at the end of the life of the mine. Poor start-up performance can put projects into financial jeopardy. The gold mining industry regularly experiences start-ups ranging from good to poor. Problem areas, which affect start-up performance, include shortcomings in ore reserve sampling and testing, equipment design and installation, untrained plant operators, inability to cope with problems which arise, and organization of the maintenance program. An investment, equal to 0.5% to 1.0% of plant capital cost, in programs to prepare for start-up, in advance, is recommended. Investment in such a program will make a good start-up possible. Without it the best result which can normally be expected is a fair start-up. Developers of new gold mines are urged to compare the cost of this investment with the anticipated increase in project net present value. Funds for this investment should be included in feasibility studies.

Jan 1, 1988

By Lawrence P. Bonicatto

The steel industry's increased demand for higher grade pellets has caused the pellet producers to investigate methods of upgrading their product. The Hanna Mining Company's Groveland plant is no exception. The Groveland Mine is located in Dickinson County on the Upper Peninsula of Michigan. The low grade iron deposit is a complex mixture of magnetite and hematite with chert, quartz, jasper, and various iron silicates. (1) Beneficiation is by Humphrey spirals and anionic flotation of the iron minerals. (2) A general flowsheet is shown in Figure 1. Flotation of the spiral tailings makes up about 75% of the concentrate. A minor amount of concentrate, less than 3%, is produced in magnetic circuits. The concentrate is pelletized at the rate of 1.6 million tons per year.

Jan 1, 1968

By J. L. Kohler

The knowledge-based expert systems (KBES) is a potentially powerful technique to the mining engineer in traditional areas of mine design and operations, as well as in the emerging areas of mining automation and robotics. Since KBES is still experimental in many respects, caution must be exercised as this "high tech" tool is developed and applied to mining. The objective of this paper is to demystify expert systems by introducing the elements of KBES, discussing the strengths and weaknesses, and identifying some areas of application in mining, based on the authors' experiences.

Jan 1, 1986

By Verya Nasri

This paper will present the design and construction of a deep underground station of the Réseau Express Métropolitain (REM) project; the Édouard Montpetit station. The Édouard-Monpetit station is an interchange station that will connect the deeply sitting REM tracks to the existing metro station of the same name located closer to the surface. Édouard-Montpetit station is expected to be the deepest in North America, surpassing the famous Forest Glen Station. The various challenges and solutions put forth for the successful completion of this underground work are presented to serve as a valuable example for future deep excavation performed in urban area, in the close vicinity of highly sensitive structures.

Jun 13, 2021

By Robert L. Wade

The two primary goals in underground coal mining are to improve safety and to lower mining costs per ton through increased productivity. However, as evidenced by the drastic decrease in. productivity since the enactment of the 1969 Coal Mine Health and Safety Act, (the Safety Act), these goals appear to be mutually exclusive. Millions of dollars have been spent in the res, arch and development of systems to solve this problem. Before the Safety Act, "productivity had experienced a 25-year history of continued increases ...? (Douglas, 1980). But since its enactment there have been dramatic decreases in productivity accompanied by phenomenal increases in mine costs. Labor trends, depletion of the more readily minable underground coal reserves and other factors have contributed to this situation, but the dominant factor is undoubtedly the Safety Act itself. To illustrate, prior to 1969 underground coal mine production was much greater than surface mine production but since then underground mine production has been declining at a rate greater than the overall growth rate of total coal production.

Jan 1, 1985

By William G. Pariseau

The purpose of this paper is to present a discussion of the various approaches that can be utilized in the study of mine subsidence phenomena. Attention is focused upon the rational selection and use of laboratory models. Broadly interpreted, mine subsidence is the deformation of the rock mass enclosing the mine. Depending upon a number of factors, the movement of the subsiding rock mass may be such as to disrupt gas and water lines or other buried utilities, to damage surface structures such as buildings and bridges, to dislocate streams, roads, and rail lines, to aggravate acid mine drainage and fire problems, and to generally mar the landscape. It is clearly a problem that no mine manager can safely ignore. It is also a problem that will grow with the general population increase. In the following, a summary review of past and present approaches to subsidence studies is given. The possibilities of duplicating subsidence phenomena in laboratory models are examined, and an analysis of a particular type of model is presented. Some preliminary results obtained from a model of the particular type analyzed are then discussed.

Jan 1, 1968