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By E Garbarino, P Molina, V Badino

Given the ever increasing quantity of construction and demolition waste (C&DW), one of the most challenging issues presently facing policymakers and public administrators in Italy concerns how to organise and manage collection and recycling and to understand whether and to what extent recycled aggregate can complement natural building aggregates in a sustainable supply mix (SSM). The paper presents the results of a research aimed at analysing energy and environmental implications of the C&DW recycling chain in the administrative territory of Provincia di Torino in northern Italy. In respect of a population of about 2.25 million inhabitants, the annual production of C&DW in the area under study is 1.8 Mt. A combined geographical information system (GIS) and Life Cycle Assessment (LCA) model was developed, paying attention to the geographical location, land use, transportation network and avoided landfill: crucial issues for sustainable planning and management. Around 90 recycling plants were classified according to the size, typology (stationary, semi-mobile and mobile) and physical- mechanical characteristics of the recycled aggregate. Under different assumptions relevant to the delivery distance, and considering the typology and grade of recycled aggregate, as well as local availability of natural aggregates, it was possible to evaluate the geographical coverage of aggregates demand and to use LCA in order to identify and quantify energy and environmental indicators.

Jan 1, 2009

By P M. Hetherington, F A. Pym, M P. Murphy, K E. Crook

Consultants in the mining industry have the opportunity to visit interesting deposits all over the world. Each deposit has its own set of challenges to face when it comes to defining and understanding the deposit geology and the economics to make it viable for extraction. Some of the challenges can include appropriate data capture, sampling techniques, structural characteristics, geochemistry, geophysics, lithology definition, and economic boundaries. It is essential that the practices used at each deposit (eg drilling, sampling, geological modelling, resource estimation etc) are documented and the results obtained are robust and defensible. The Competent Person is not always aware of instances where their resource estimation practices have not been substantiated. ‘You don’t know what you don’t know’ is a phrase frequently used during a mineral resource audit. Technical work to substantiate drilling, sampling, density, assaying, geological modelling and estimation processes is not always completed. Audited Competent Persons often comment: • ‘I was unaware that this was required.’ • ‘I have not had training in this area and do not know how to complete the checks required.’ • ‘This is how we’ve always done it.’ Examples of audits where it was found that geological practices were not substantiated are examined here. A discussion is included on why substantiation of these practices is important, and potential reasons as to why there are instances of unsubstantiated processes and practices are discussed.

Mar 22, 2022

By Dennis J. Callaghan

This report is the result of information obtained from a review of related literature, personal inquiry and on-site examination of active surface coal mining operations. Four improved surface coal mine systems are described in detail and evaluated for feasibility, implementation requirements, environmental benefit and costs. Engineering feasibility emphasizes equipment availability, compliance to design requirements, practicality and industry rating. Implementation potential emphasizes immediacy, ease, acceptability and constraints. Special attention was given to environmental responsiveness, both with regard to the solutions to mined-land reclamation problems and to the concurrency of reclamation. Each system description includes a hypothetical model mine with a depreciation schedule, capital summary, estimated annual production costs, sales price computation, production and operating cost summary, and a sensitivity analysis of mine price to stripping ratio. A program plan and time schedule for demonstrating a selected mining system covers site selection criteria, mine data collection, criteria for controlling and budgeting costs and reporting findings. Ten additional mining methods and techniques are briefly described and evaluated. Common reclamation problems are listed and described. Sixteen state reclamation laws and regulations are abstracted. Sixty-nine references are listed in the bibliography.

Jan 1, 1976

By J. L. Eakin

The works and opinions of experts on well stimulation and related problems are summarized in this paper. The material is devoted to stimulative work in petroleum and natural-gas wells exclusive of the generally applied pressure maintenance and secondary-recovery methods. Its purpose is to review a collection of recent and available material on well-stimulation methods and techniques. Each separate discussion is accompanied by a selected bibliography. An author index is included.

Jan 1, 1964

By J. L. Eakin

The works and opinions of experts on well stimulation and related problems are summarized in this paper. The material is devoted to stimulative work in petroleum and natural-gas wells exclusive of the generally applied pressure maintenance and secondary-recovery methods. Its purpose is to review a collection of recent and available material on well-stimulation methods and techniques. Each separate discussion is accompanied by a selected bibliography. An author index is included.

Jan 1, 1964

By Alfred Petrick

This report analyzes the byproducts systems of lead, zinc, uranium, rare earths, iron, aluminum, titanium, and lithium. Specific byproduct metals covered are cadmium, germanium, indium, and thallium from the zinc system; antimony and bismuth from the lead system; vanadium, radium, and scandium from the uranium system; rare-earth oxides from the rare-earth system; and cobalt, gallium hafnium, and rubidium from other systems. The report discusses various metallurgical systems, marginal and incremental production costs of byproduct subsystems, industry structure and organization, and historical data on price, consumption, and supply.

Jan 1, 1973

By R. P. D. Graham

It is almost exactly two hundred years since the foundations of the mining and metallurgical industries in Canada were laid. There '."'as nothing spectacular about this early start. It had to do with the most basic phases of these industries-the mining of coal and iron ore, and the manufacture of cast and wrought iron. At several points along the coast of Cape Breton island, coal seams may be seen outcropping quite conspicuously, and it is probable that they had been observed, and possibly worked in a small way, in very early times. However that may be, these coal seams have the distinction of being the first in North America of which there is any printed record, reference to them appearing in a volume by Nicolas Denys which was published in Paris in 1672. Regular coal mining in the district did not commence until about fifty years later, however. The metallurgists started their operations along the north shore of the St. Lawrence river. Here, at many points between Montreal and Quebec, are to be found deposits of bog iron ore, and in 1 730 a furnace for smelting such ore was established on the St. Maurice river. The St. Maurice forges continued in operation until 1880, and throughout that long period they were famed for the fine quality of castings produced, and also for a-superior wrought iron.

Jan 1, 1924

Explosives identification tagging refers to the addition to explosives, during manufacture, of coded microparticles that can survive detonation, be recovered and decoded, and allow the explosives to be identified and traced to the last legal possessor as a result of distribution records kept of the coded tagged explosives. This study seeks to prepare the way for National implementation of identification tagging of all dynamites and cap-sensitive slurries (also known as water gels) by resolving technical issues and by developing a plan for pilot testing of the program. It is presented in two volumes: Volume I, National Implementation Model, and Volume II, Pilot Test Plan.

Jan 1, 1977

By Alfred Traverse

The Brandon lignite is a small deposit of very low rank coal near the village of Forestdale in the town of Brandon, Vt. It occurs in association with other sediments, principally sands and silts. This lignitic coal has attracted considerable scientific interest since the middle of the 19th century because of the abundance of fossils in the sediment and the rarity of lignite in New England. A cooperative investigation has been developed by E. S. Barghoorn, W. Spackman, and the author in which different phases of the problem have been worked on in a coordinated research program. This paper presents results of an investigation of the very abundant fossil pollen and spores and some other microfossils of the deposit. The studies on which this manuscript is based were made in large part at Harvard University in partial fulfillment of the requirements for a Ph. D. degree.

Jan 1, 1955

Jan 1, 2001

By Alfred Opengart

During any rush hour, tens of thousands of automobiles clog the main highways leading into or out of our large cities. Inevitably one or more cars stall or plow into another, causing a momentous traffic jam. Traffic backs up for miles as drivers try to maneuver around the roadblock. As commuters, we grin and bear the inconvenience, rationalizing the delay as part of the price one pays to live in a modern society. The truth of the matter is that the engineers planning the roads have the know-how to build adequate bypass alternatives into their design. The problem is one of economics -- can the cost of eliminating roadblocks be justified? Engineers designing solutions to complex materials handling problems for modem distribution centers are just now beginning to ask this question in relation to their work. Unfortunately in many instances, it has taken an expensive "traffic jam" to bring this question to the front. In these cases, a seemingly practical system promising an attractive return on investment -- using the latest equipment and computer controls -- was designed and installed. Everything went according to plan until one day a breakdown occurred. .Product flow stopped, and management realized it was at the mercy of the "machine." In such situations, management had assumed it could minimize the risks of the breakdown by injecting extra manpower to operate the system manually and pay the associated costs. What it had not recognized is that manual intervention is nearly impossible with sophisticated systems. Thus, too often -- and sometimes too late -- management found itself footing a very high bill for losses incurred because of major production stoppages and missed customer shipments.

Jan 1, 1973

By D. Harrington

The record of fatalities from mine explosions in the United States during the past 3 years has been the best in the history of the mining industry. During these 3 fiscal years, mine explosions have resulted in an average of 4I0 deaths per year, as compared with an average of 153 deaths per year for the preceding; 5 years; an average of 542 deaths per year for the 3-year period 1907-09, inclusive, just before the organization of the U. S. Bureau of Mines; and a yearly average of 265 deaths per year for the 20-year period prior to 1929. This remarkable reduction in deaths from mine explosions demonstrates clearly that mine explosions can be controlled; in fact, they can be prevented when or if the mining people of the United States see fit to take the readily available precautions necessary to bring about this desirable objective. Several large coal-producing States, which in the past have had numerous disastrous explosions, have been free from such disasters for continuous periods of as much as 6 years or even longer. The bituminous mines of Pennsylvania, the largest coal-producing State, give a good example of what can be done to prevent explosions; this State has had only one major explosion (and it resulted in 7 fatalities) during the past 6 years, and no explosion occurred in the several hundred bituminous-coal mines of the State during the past fiscal year. This is a truly remarkable record when compared with past performance in any year in the operation of coal mines in Pennsylvania.

Jan 1, 1936

By J Field

Many aspects of water use in mining are driven by the technical requirements for water. There has been little consideration given to both the safety and the health requirements. Workers in the mining industry are exposed to water from a range of treated and untreated sources. The intended use of this water dictates the required quality of the water, sometimes with limited consideration for contact with miners. Particularly for underground workers, there is exposure while working in and walking through groundwater possibly contaminated by hazardous substances. Where controls are inadequate the outcomes of this exposure can result in disease, illness and injury û the costs of which can be significant. The situation could also arise where, due to the lack of human exposure, the controls are unwarranted and the financial cost unjustified from a health perspective but warranted from an equipment management standpoint. In addition to the health aspects, water can impact on a range of safety issues resulting from high pressure usage, dust suppression, fire fighting and other processes. The protocols and procedures in place need to consider the safety issues in addition to managing water usage. The current state of water management in mines from an occupational health and safety perspective has been ascertained from a survey targeting underground and surface coal and metalliferous mines. This survey considered the health and safety issues associated with water use, the types of surveillance, control protocols and the strategies that the mines have in place to manage the health and safety risks associated with water systems. The results assisted in the identification of potential occupational health and safety risks associated with water systems and the management processes that may be appropriate from a risk management perspective. Health and safety issues are often neglected but remain critical issues affecting the value of water to the mining industry.

Jan 1, 2006

By W. Leblanc, J. Phalen

This paper tells the story of a serious mine fire on a mechanized longwall face in a submarine coal mine at Glace Bay, Nova Scotia. The story gives, in chronological order, a technical account of the steps taken to investigate, fight and contain the fire. The time during which the events took place spans from June 19 to November 7, 1975.

Jan 1, 1976

By W. E. Roscoe

"Mineral exploration properties are those on which an economically viable mineral deposit has not yet been discovered. Such properties are bought, sold, optioned and joint ventured on the basis of their perceived potential for the existence and discovery of a viable mineral deposit. The intrinsic value of an exploration property is therefore based on the exploration potential. One measure of the exploration potential is the amount that can be justified to spend on exploration for a viable deposit.The appraised value method uses a cost approach to value exploration properties. It is based on the premise that an exploration property is worth the meaningful past exploration expenditures plus warranted future costs to test remaining exploration potential. Results of past exploration work are analyzed in order to retain only those past expenditures that are productive in terms of identifying remaining potential. Warranted future costs comprise a reasonable exploration budget to test that potential."

Jan 1, 2002

By C. Morlot, C. Auvray, E. Fourreau, J. Talandier

"During the excavation of underground galleries in a rock mass, reorganisation of the stress field around the site results in damage to the surrounding material. In the framework of research undertaken at the ANDRA underground laboratory in France, galleries have been excavated in a Callovo-Oxfordian argillite formation. The damage has manifest as a number of fracture systems in the adjacent rock. Observations have shown that fractures generated during excavation and storage exploitation are able to self-seal during re-saturation of the site in the post-closure stage. Although indirect evidence for argillite self-sealing has previously been reported, from experiments performed both in situ and on samples, no direct observations of self-sealing have yet been made.For the present study, we performed a range of self-sealing experiments using a newly-developed triaxial compression cell placed within a nano-CT scanner with a 10 µm resolution. The body of the compression cell is X-ray transparent, allowing sample healing to be monitored directly. The samples contained an artificial fracture that had been generated in the laboratory, into which a fluid was injected. The fractures were orientated either perpendicular or parallel to the plane of anisotropy of the material. Our initial results demonstrate that when fluid is injected perpendicular to the plane of anisotropy, the flow-rate has no apparent influence on the kinetics of fracture closure. Permeability varies significantly, from 2.10-14 to 2.10-18 m2 over 116 hours. Post-test observations of the fracture lips show swelling that appears to be orientated perpendicular to the fracture plane and therefore parallel to the plane of anisotropy. Initial results for an injection parallel to the plane of anisotropy suggest that, in this case, the rate of flow affects the kinetics of fracture closure. For a flow-rate of 0.25 ml/min, closure begins after around one minute. In contrast, for a rate of 0.05 ml/min, it is necessary to wait several minutes before partial sealing of the zone is observed. The reduction in permeability is again significant, from 2.10-15 to 4.10-18 m2 over 96 hours. After completion of the test, swelling was observed in elongated zones that lie parallel to the fracture plane and therefore to the plane of anisotropy."

Jan 1, 2015

By M D. Winning

The historical development of the elemental sulphur recovery industry in Western Canada is reviewed for the period 1952 to 1965. A brief technical description of a typical modified Claus sulphur recovery unit is presented. Some predictions are made concerning the future of the elemental sulphur recovery industry in Western Canada. THERE are evidences of sulphur or its compounds having been used for religious and medicinal purposes as far back as we have a recorded knowledge of history. As typical examples, sulphur was burned as a sort of inverse incense to drive away evil spirits at religious festivals, sulphur ointments were used by the early Egyptians to cure eye ailments, and hot sulphur-spring water was used as a cure for a variety of ailments. Thermopyle was called "Hot Gates" be-cause of its fame as a spa as well as a mountain pass. The Romans discovered the sulphur deposits in Sicily and mixed sulphur with bitumen for incendiaries; and, of course, anyone familiar with the travels of Marco Polo knows about the Chinese development of gunpowder, which contains sulphur. In some aspects things haven't changed much today. We still use sulphur-bearing ointments, and we still use the hot sulphur springs such as the one at Banff in Western

Jan 1, 1965

By John F. O'Leary

The paper review the process the minerals industry and the materials revolution. For a long time, Latin América attemps at industrialization have been attempts in part, by need to important some of the many raw materials that industrial nations must have. However, the industrial sistem may be in for some of the many raw materials that drastic changes would increase the mineral self sufficiency of countries that are industrialized. In this way, the materials revolution would be a boom to Latin America, it would reduce some of the serious obstacles to the goals which all Americans seem to share.

Nov 20, 1969

By E. E. Mueser

As Mr. Lundberg has already ably covered the theory of various methods of electrical prospecting, I shall confine my remarks to a consideration of the features which must obtain in an electrical prospecting method in order that it may be useful from a practical standpoint. These remarks I shall make with particular reference to the Elbof method. The successful application of all these methods rests, in the first place, upon the possibility of correlating theory, or empirically established facts, with the field data. Their practical usefulness, however, requires that the technique of making the field observations, and the procedure itself, be such that the method may be applied to large areas, under normal average conditions. The method, therefore, should not involve excessive preliminary labour costs to prepare the ground for actual prospecting work, nor should the prospecting work itself be so slow that its cost, when applied to extensive areas, becomes prohibitive. Moreover, it should be possible to apply the method even under difficult terrain conditions, such as rough topography and dense vegetation. It may be said of most of the methods referred to in the preceding paper, that, while they are interesting and theoretically sound, they fail to meet such practical requirements as I have outlined.

Jan 1, 1926

By N. Damiano, J. Noll, C. Zhou, J. DuCarme

"Preventing machine-related injuries is one of the major safety concerns in underground coal mines. Severe injuries and fatalities occur when a miner is struck, crushed, or pinned by mining equipment such as a continuous mining machine (CMM), shuttle car, or a scoop. Proximity detection systems (PDSs) have been applied in mining to reduce these types of injuries and fatalities. All of the PDSs that are currently approved by the Mine Safety and Health Administration (MSHA) for use in underground coal mines are magnetic-field based and could be affected by metallic objects such as trailing cables. Researchers from the National Institute for Occupational Safety and Health (NIOSH) investigated the influence of trailing cables on the performance of PDSs. In particular, the magnetic field coupled from proximity system generators to a de-energized trailing cable were characterized. The results show that significant energy can be coupled from the proximity system generators to a trailing cable when there is a closed loop in the cable. The effect on PDS performance from the magnetic field radiated around an energized trailing cable was also quantified for different current amplitudes in the cable. It is shown that the magnetic field caused by the electric current in the trailing cable mainly consists of a 60-Hz signal and its harmonics which cause little interference to the PDS. The results presented in this paper can help PDS manufacturers to design better systems that are more immune to these effects. INTRODUCTION An average of 250 injuries occur every year during operation of Continuous mining machines (CMMs), and 43 miners have been killed by striking or pinning accidents involving CMMs in the U.S. from 1984 to 2015 (Mine Safety and Health Administration, 2015). In addition, there have been 10 fatal accidents involving mobile haulage equipped with trailing cables from 2000 to 2015 (Noll et al., 2017). In response to these fatalities and injuries the Mine Safety and Health Administration (MSHA) promulgated a regulation in 2015 requiring the use of a proximity detection system (PDS) on all CMMs except full-face machines and proposed a regulation in 2016 which would require a PDS on other mobile underground equipment. Current PDSs approved for underground use are magnetic-field based. The PDS contains machine-mounted magnetic field generators that create fields around the machine. The other part of the PDS is a miner-wearable component (MWC) that reads the flux density of the generators. These systems use the magnetic field strength readings from the MWC to determine whether a miner is at a safe distance from the machine. A stable magnetic field is essential for the accuracy of the system."

Jan 1, 2018