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By J R. Leeming

Mining law has developed in Great Britain (GB) over centuries, mainly in response to lessons learned after disasters and other major incidents. This has led to a culture of preventing repeat accidents, rather than predicting and controlling unsafe acts or conditions.This paper explains how, initially in response to a government drive to reduce the burden on industry, the opportunity was taken to review and reform all 48 sets of GB mining-specific law into a single document. The philosophy adopted, the procedure followed and the significant changes that resulted are explained.CITATION:Leeming, J R, 2017. The complete renewal of Great Britain’s mining laws for the 21st century, in Proceedings Australian Mine Vent Conference 2017, pp 3–8 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Peter de Bakker

The objective of this contract was to develop a simple, reliable, economical, remote-control roof bolting module for installation of mechanical and resin bolts. It was to be capable of placing longer than seam height bolts, up to 10 ft lengths, from a seam height of 36 to 72 in., while keeping the operator under supported roof. The resulting machine, called REM-Bolter, is a low profile unit that utilizes Foster-Miller Flexible Shaft Roof Drill, a Bendix Roof Bolt Inserter and a newly designed. Roof Bolt Lifter/Torquer. Every effort was made to strike a compromise between complete automation and complete manual control. In a controlled laboratory environment the REM-Bolter remotely installed 1000 bolts. Subsequently the machine was tested in an operating coal mine where 500 holes were drilled (and an equal number of bolts were installed) remotely, over a 4 month period. The results of all tests Live shown that the operator of a machine of this kind can quickly, and repeatedly, install rootbolts remotely from his operator compartment some 8 ft away from the drilling/bolting action. The report includes recommendations for improvements to the present REM-Bolter design that would translate the present test bed into a second generation test bed and a potential first generation production unit.

Jan 1, 1983

By François Robichaud

"The Laronde mill has been in operation since 1988. Actual milling rate ranges from 7,000 to 8,500 mtpd. Laronde uses SAG/ball mill grinding followed by copper and zinc flotation circuits. A cyanidation/Merrill-Crowe process recovers the remaining gold and silver in the flotation tails.In 1999, the carbon in pulp circuit was replaced by a Merrill-Crowe circuit in order to cope with a much higher ratio of silver/gold associated with the discovery of the Penna shaft. Marine type diatomaceous earth was used as filter aid in both clarifier pressure leaf filters and recessed pressure filter presses from 1999 to 2005. In 2005, this filter aid was gradually replaced by alpha-cellulose after several laboratory and plant filtration trials. The selected cellulose is considered to be much less sensitive to parameters such as pH and reagent concentration and have increased clarifier and filter press filtration performance. Also, since cellulose is exothermic, replacing diatomaceous earth with cellulose as filter aid in the filter presses has increased calcining and oxidation rates in the calcining ovens since cellulose is exothermic. Finally, better calcining conditions have resulted in energy and reagent savings at the arc furnaces.This paper describes how the filter aid replacement has contributed to increasing productivity and Net Smelter Return of the refinery while reducing worker’s hazards and operating cost.INTRODUCTIONAll Merrill-Crowe circuits in the world are operated with filter aids. For years, the market for precoat filter aid has been dominated by mineral filter aids such as diatomite and perlite. Flowsheet and equipment selection at the Laronde refinery were performed in the late nineties. At that time, some key parameters of the design criteria had clearly identified marine type diatomaceous earth (DE) as the most successful filter aid. Parameters such as reagent cost and availability, clarity of the filtrate solution and good historical filtration performance in other concentrators had designated DE as the best suited filter aid. Pregnant solution processed in the refinery from its start-up through 2001 was fairly stable in flow rate and reasonable in terms of impurity content (cationic and anionic compounds)."

Jan 1, 2007

By J. C. Borland, J. H. Rogerson

Jan 1, 1963

By D. E. Kirby

The electrochemical reduction of AlC13 was investigated as a process for the production of aluminum. An externally heated, single-compartment cell with a rammed refractory lining was used with molten KCl-NaCl-AlC13 electrolyte. Aluminum was deposited qt 700° to 760° C with a current of 100 to 200 amperes on a molten aluminum cathode. Chlorine was evolved at a graphite anode and collected and measured to provide a quantitative evaluation of the AlC13 reduction. Aluminum was removed from the cell by siphoning or ladling. Granular AlC13 was added periodically to replenish that depleted from the electrolyte. Concentrations of 7.5 to 17.5 percent AlC13 in the electrolyte were optimum for operation. Anode current efficiencies of 83 to 85 percent were attained, using anode current densities of 5.9 amperes per square inch and an anode-cathode distance of 4 inches. The chemically bonded, alumina liner was resistant to attack by aluminum and chlorine but susceptible to erosion at the surface of the electrolyte. Titanium diboride proved suitable for the electrical connection to the molten aluminum cathode. Aluminum of a purity equal to or better than 1100 series metal was electrowon continuously from commercial AlC13 for a period of 4-1/2 months.

Jan 1, 1970

By T. Frömmer, H. Wagner

An inter-disciplinary geotechnical study has been carried out in an Austrian magnesite mine. The paper describes the how geological data, in situ and laboratory tests as well as subjective, empirical, geophysical and numerical methods have been used to identify critical areas in the mine. In einem österreichischen Magnesit Bergbau wurde in den letzten Jahren eine interdisziplinäre geotechnische Studie durchgeführt. Der Vortrag beschreibt den Einsatz subjektiver, empirischer, geophysikalischer und numerischer Methoden zur Identifikation geotechnischer Problembereiche Ces dernières années des études géotechniques interdisciplinaires sont effectuées dans une mine souterraine de magnésite en Autriche. Ce rapport trace l’application des méthodes subjectives, empiriques, géophysiques et numériques pour identifier les zones problématiques dans la mine

Jan 1, 2003

By John L. Ellenberger, Gabriel S. Esterhuizen

Observations of pillar conditions in limestone mines showed that the presence of weak bands in the limestone can result in pillar damage at stresses that are lower than one would otherwise expect. The objective of this National Institute for Occupational Safety and Health study was to investigate the mechanism of failure caused by the presence of weak bands by using a series of numerical models based on realistic physical properties. The effect of the weak bands on pillar strength was also investigated by developing a series of pillar models with different width-to-height ratios and determining their strength by simulating a servo-controlled loading condition. The material properties of the bands and the limestone were varied and their effects on pillar strength were determined. Model results demonstrated failure development similar to the pillars observed in the field. The weak bands were seen to develop tensile stresses in the limestone as they extrude under increasing stress. The limestone fails in tension at a much lower stress than its expected uniaxial compressive strength. The results showed the load bearing capacity of the pillars can be reduced significantly by the presence of multiple thin weak bands. The degree of strength reduction is largely dependent on the compressive strength, the frictional resistance and the thickness of the weak bands. Single weak bands do not affect pillars as severely as multiple bands. However, the model results show that a single thick weak band, which comprises more than about 2 percent of the pillar height, can cause a significant reduction in pillar strength. The weakening effect of the bands become less severe as the pillar width-to-height ratio is increased. Field observation of spalling and failure associated with weak bands in limestone pillars show that the failure mechanism in the models resembles the observed failure. The model results provide insight into the important factors affecting pillar strength in the presence of weak banded materials.

By John K. Alley

Despite the extensive use of fluorphlogopite, investigators do not agree as to its exact melting temperature. Data on other fluormicas and on related fluorsilicate systems are largely nonexistent. A knowledge of the melting temperature is necessary for the effective synthesis and use of fluorphlogo¬pite or other fluormicas. The increasing use of two- and three-mica systems to yield polycrystalline ceramics has made more urgent the need for melting temperature information concerning these other fluormicas. This report is part of a program by the Bureau of Mines to synthesize large-size or large-crystal fluorphlogopite and develop a usable reconstituted fluormica sheet. The melting temperature of fluorphlogopite, K2Mg6A12Si6020F4, was found to be 1,383° ±2° C. This temperature was found by studying single crystals of fluorphlogopite, heating behavior of glass of fluorphlogopite composition, and the actual crystallization of fluorphlogopite from a melt that had been heated above 1,430° C. The formation of forsterite or norbergite was directly proportional to the loss of volatiles during the experimentation. Many trials revealed that the only reliable seal was a thick platinum sheet with welded seams. If no volatiles were lost, neither norbergite nor forsterite were formed; fluormica was then the only product. Excellently formed crystals of forsterite with an optical sign different from ordinary forsterite were obtained during the single crystal melting experiments. These crystals resulted from a slow loss of volatiles. A congruent melting of fluorphlogopite is indicated by the data of this report; however, incongruency within a small temperature range is not precluded. A more refined method using phase equilibria-quench methods would be necessary to settle the question absolutely.

Jan 1, 1962

By K. Nong, H. F. Fuls

The quality of Pregnant Leach Solution (PLS) at Skorpion Zinc is of utmost importance for efficient operation of the Solvent Extraction (SX) Plant. Suspended solids in the PLS forms CRUD in the settlers, resulting in reduced zinc transfer capacity and increased impurity carry over to Electrowinning. The Ishigaki Fibre-Wakishimizu filter (fibre media rapid filtration equipment) has been identified as polishing filter that potentially could remove solids from the PLS of Skorpion Zinc. A pilot unit with 20m³/h capacity was tested on site over a period of 9 months under plant operating conditions in the refinery. The FW filter produces a clear filtrate, acceptable for the Solvent Extraction. Turbidity is improved by 72%. Gravimetric analysis indicates a 47% removal of solids. However, the gravimetric method is biased by a co-precipitation of saturated salts during the analysis. Filter media is blinded by the Skorpion Zinc PLS solution, as result of suspended solids and process chemistry. The media could not be regenerated to acceptable conditions. Further testwork to investigate the impact of process solution chemistry modification on blinding is undertaken. Based on the outcome of this investigation a final decision on the FW filter can be taken.

Jan 1, 2007

By Peter Waggitt

Northern Australia has been home to uranium mining for over 70 years, more or less continuously. In the early days, post World War 2, there was little effort made to remediate workings at the end of operations. The three “campaigns” of uranium mining (1951-55; 1960-70; and 1979-present) are all now in various stages of remediation. This includes not only the large legacy site at Rum Jungle but also smaller fields like the South Alligator Valley, as well as contemporary works at Nabarlek and the ongoing closure at Ranger– Australia’s longest operating uranium mine. This paper briefly describes some of the past remediation activities before providing an update on the Ranger closure programme and future timetable.

Jan 1, 2020

By Donald W. Ross

"INTRODUCTION Sponge iron has been made commercially since 1912 at a Swedish ceramic plant; and the product, known as Swedish disk—type sagger sponge iron, has an excellent reputation as a superior furnace feed wherever high—grade steels are made. The general procedure for making brickyard sponge iron was described frequently in Swedish technical journals prior to 1932 and at that time consisted in filling clay refractory containers, called saggers, with a super-concentrate of Gellivare magnetite plus the necessary amount of solid reducing agent and desulfurizer and then firing in a Hoffmann ring furnace, as used in the ceramic industry.The early Swedish publications describe two types of brickyard sponge iron: (1) An inferior high-sulfur product obtained by mixing the ore and reducing agent, and (2) a high-grade low-sulfur product in the form of coherent disks 7 to 9 inches in diameter and 1 to 1-1/2 inches thick made by the saggers with alternate layers of solid-fuel reducr and of uniaxed ore."

Sep 1, 1945

By William H. Holley

Thirteen additional preservative/fire retardant systems were applied to Ponderosa pine and evaluated for flammability both before and after water leaching. The more promising four systems were given a thorough evaluation for flame spread, toxic gas and smoke density levels, resistance to decay, and compressive strength. The most promising system on the basis of history of usage in the mine, ease of application and low cost as well as overall performance is the Fyreprufe/ACC Albi 107A/ 144 combination. A survey of inspection tools and instruments, identified equipment which could be assembled into an inspection kit for use in determining the extent of decay and/ or impregnant retention levels in mine timber. A literature search identified those high fire hazard areas found in a typical mine. Timber and other wooden structures used in such areas should be treated with an acceptable fire retardant system. A survey of insurance companies revealed that the use of such treated timber in the mines would probably have little or no impact on the rate structure.

Jan 1, 1980

By Joseph Ribak

Grunerite asbestos (amosite) has been shown in epidemiological and experimental animal studies to cause lung cancer, mesothelioma and pulmonary fibrosis commonly referred to as asbestosis. An overview of the human and experimental animal studies describing the health hazards of grunerite asbestos (amosite) is presented. Of the many human studies describing the health hazards of asbestos, only three factories using mainly, if not exclusively, grunerite asbestos (amosite) have been studied. The first is a series of reports on a cohort of 820 workers from a plant located in Paterson, NJ. Among this cohort, 18.7% died of lung cancer and 17 mesotheliomas occurred. The Paterson factory closed in 1954 and moved to Tyler, Texas where it operated until 1972. Among the 1130 former workers in the Tyler plant 6 mesotheliomas were reported with 15.8% lung cancer mortality. The third grunerite asbestos (amosite) exposed cohort was an insulation board manufacturing facility in Uxbridge, United Kingdom. Here 17.1% of the workers died of lung cancer and 5 mesotheliomas occurred. The lung content from 48 Uxbridge workers was analyzed by analytical transmission electron microscopy for mineral fibers. The relationship between grunerite asbestos (amosite) concentrations in the lung correlated with grades of fibrosis and asbestos bodies and was lower than the concentration found in the cases with malignant tumors. The lung cancer cases contained more grunerite asbestos (amosite) than mesothelioma cases, and in the cases of non-alignant disease the concentrations were still lower. In both types of malignancies the concentration of grunerite asbestos (amosite) was very high-over a billion fibers per gram of dried lung tissue. Occupational exposure to airborne concentrations of between 14 and 100 fibers of grunerite asbestos (amosite) per milliliter after 20 year latency causes marked increases in lung cancer, mesothelioma and pulmonary fibrosis (asbestosis). © 2007 Elsevier Inc. All rights reserved. Keywords: Grunerite asbestos; Amosite; Mesothelioma; Asbestosis

Jan 1, 2007

By Shemek Oginski

The 5 km (16,194 lf) of 6.1m (20 ft) diameter TBM driven tunnel built by the J.F.Shea Co. will serve as sewage overflow storage. The TBM tunnel and four connecting tunnels excavated by drill and blast methods in hard granite will remain unlined. Based on the Geotechnical Baseline Report (GBR), the Contract documents provided a design with no required pattern of rock bolts, no probing, no pre-excavation or consolidation grouting, and lastly, no final lining of the tunnels was deemed necessary. This paper will provide a general overview of these topics with the emphasis on the actual ground conditions encountered versus the projected conditions provided in the GBR and how the GBR reflected the design of the project. Proposed modifications to the temporary and permanent ground support will be presented and the necessity of probing and pre-excavation grouting will be evaluated.

Jan 1, 2005

By John P. Shubilla1, Nicholas Kyriazi

A joint effort by the Pittsburgh Research Center (PRC) and the Mine Safety and Health Administration (MSHA)3was undertaken to determine how well self-contained self-rescuers (SCSR's), deployed in accordance with Federal regulations (30 CFR 75.1714), held up in the underground environment with regard to both physical damage and aging. This report presents findings regarding laboratory-tested SCSR's in the fifth phase of testing from mid-1993to early 1996. The SCSR's were tested on human subjects and on a breathing and metabolic simulator (BMS) at PRC. These results indicate that most of the apparatus, if they pass their inspection criteria, perform satisfactorily.

Jan 4, 1996

By David D. Rabb

A report on location, sampling, assays, mineral examination, amenability leach tests, and evaluation of certain mine dumps in Mohave County, Arizona. Extractions of greater than 30 percent of the gold and silver were achieved during simulated heap leaching of selected mine dump material. Consumption of reagents was relatively low and results suggest leaching of prepared heaps is technically viable and could be economically attractive.

Jan 1, 1980

By Randall M. Wheeler, Kenneth K. Eltschlager

Blasting Seismographs use microphones to measure air overpressure from blasting. The microphone height above the ground has been the object of some controversy. The current ISEE “Field Practice Guidelines for Blasting Seismographs” specify microphone placement within 1.2 inches of the ground or over 3 feet above the ground. In this study, air overpressure measurements were taken at different height intervals and compared. Blasting seismographs constructed to the ISEE “Performance Standards for Blasting Seismographs” were used to monitor construction, quarry, and coal mine blasting. Near and far field measurements were taken to obtain representative spectral and amplitude ranges. The comparative analysis shows that microphone height has negligible impact on air overpressure measurements.1

Jan 1, 2005

By P. C. Schutte

Ergonomics is the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance. Despite the fact that the application of ergonomics principles can make a major contribution to the management of significant occupational safety and health risks, ergonomics is currently applied on a limited scale in the South African mining industry. The objective of this paper is to provide a perspective of ergonomics, the main aim being to create a point of departure for the development of strategic objectives to enhance existing health and safety initiatives through the application of sound ergonomics principles. Two of the major consequences of poor ergonomics, namely work-related musculoskeletal disorders and worker fatigue, and possible means of introducing ergonomics into the South African mining industry, are discussed.

Jan 1, 2005

The Gippsland Basin, southeastern Australia, has an Upper Cainozoic history of episodic change of hydrology and the related environment, reflected in the geomorphology and surficial deposits of the onshore basin and the hydrodynamically controlled accumulations of petroleum of the offshore basin. Succeeding this episodic pattern, man through a number of activities, has had a sudden and major impact on the hydrology and the related environment. Activities include those directly affecting the groundwater system, such as extraction of fossil fuels with the consequent threat of land subsidence; irrigation and clearing of vegetation and the consequent effect of salinisation; change of land use and installation of septic tanks with resulting nitrate pollution; damming of streams and the consequent reduction in the frequency of floods with degradation of the biological Environment; de-snagging streams and construction of cutoffs with increased stream erosion, modifying wetlands including drainage, with the consequent degradation of their ecosystems; and increase in phosphate and nitrate inputs to the coastal lakes with the risk of their eutrophication.

Jan 1, 1992

By Louis Schaffer

The purposes of the research were to assess the applicability of new accident investigation methods to mining accidents, and to adapt those found to be applicable in the development of a new methodology for use in mining. The development included field testing, evaluation and modification of the new methodology. The report is in two volumes. Volume one discusses the background research, the design of a methodology for field evaluation, preliminary field tests in Utah mines, and work done to prepare for a formal, complete evaluation by federal government mine safety officials. This, volume 2, discusses the field evaluation done by the contractor and cooperating mines after the program was re-directed by the Bureau of Mines. It relates to research done during a period of approximately eighteen months, ending in April, 1983.

Jan 1, 1986