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THE National Safety Council will hold the following ses-sions in the Waldorf-Astoria Hotel, New York, N. Y., on Oct. 2, 3 and 4: Oct. 2. 9.30 A. M. 1. Report of past year committees, by Chairman 2. "Safety Pays," by Howard I. Young, Vice-President, American Zinc, Lead and Smelting Co., Mascot, Tenn. (Discussion) 3. Entertainment 4. "Methods and Results of Improved Foremanship Conferences," by H. A. Gilbertson, Director of Per-sonnel, Lehigh Coal and Navigation Co., Lansford, Pa. (Discussion) 5. Appointment of election and resolutions committees Oct. 3, 9.30 A. M.

Jan 9, 1928

By Unknown

Blast Site Security Involves: * Clearing the area * Controlling Access * Warning Signals

Jan 1, 2003

A device is described which is suitable for the automatic sampling of dust in dust laden flue gases. This device, called a Venturi Sampler, consists of two pipes each fitted with a suitably designed venturi.Both pipes are placed in the flue where one acts as an open-ended reference tube and the other as the actual sampling tube.The gas sampling rate is automatically controlled so as to maintain a zero differential pressure between pressure tappings in the two venturi throats. The venturies are so designed that under these conditions the gas velocity in the sampling pipe is always equal to the free gas velocity in the flue-that is isokinetfc sampling conditions are maintained.INTRODUCTIONThere is a constant need in industry for regular and accurate assessments of dust losses, both to assist in improving operating efficiencies in order to minimize losses, and to obtain accurate metallurgical balances. In many cases where sampling is carried out in dust laden gases, the existing sampling methods are both laborious and inaccurate, and often make no provision for changes in flue gas velocity while sampling is in progress.In the majority of cases where a measurement of dust losses in a stack or flue is required, a preliminary velocity survey is made with a pitot tube to establish the gas velocity at each of the points at which samples are to be taken. The sample of gas (and dust) is withdrawn through a tube connected via a flowmeter to an exhausting apparatus. Some means of removing the dust from the gas sample is placed in circuit ahead of the exhausting apparatus. This is often an alundum or paper thimble housed in a gas-tight container.The purpose of the flowmeter is to measure the actual flow of gas during sampling so that the sampling velocity at the inlet to the sampling tube may be calculated, and the flow corrected so that the sampling velocity will agree with...

Jan 1, 1959

By I. Jones

Geologists, engineers, technicians and surveyors have successfully utilized technical software in the mining industry for over 30 years. Software for processing survey, geology, mine engineering and planning information make these functions more efficient by automating repetitive tasks and reducing data processing errors. While these systems have been improved incrementally overtime, new systems that represent giant leaps in technology have been introduced to help mining operations increase productivity and reduce costs. However, their widespread use within the industry has left individual companies without a competitive advantage. Additionally, the ability of these applications to provide the productivity improvements required in today’s uncertain market conditions has since peaked. The next wave of technology—integration of independent software applications—is just starting to emerge and will have a significant effect on the productivity of mining operations. To reap the productivity gains required to remain competitive, mining companies must exploit the collective knowledge and experience of every employee in the organization. Integration of independent software application allows companies to leverage information from all activities, enabling staff to make better decisions to improve productivity. This paper outlines the importance of integration as productivity enabler. Key performance indicators, strategic mine planning, resources management and mine-to-mill integration are discussed as processes that enable productivity. The Gemcom Enterprise Mining System (GEMS)is introduced as the industry’s first integrated solution that enables these productive processes. The paper concludes with a comment on the level of change required to realize the benefits of integration.

Jan 1, 2003

By Youze Xu

The effect of oxalic acid, acetic acid, citric acid and EDTA on extraction of Cr (?) in soils contaminated by chromium- containing slag was investigated using a batch of incubation experiment. The results show that the pH value decreases more obvious with the increase of the amount of organic acid. The amount of Cr (?) extracted increases with increasing the amount of organic acid. When the ratio of organic acids to total Cr was 5:1, citric acid revealed the highest extraction effectiveness, followed by EDTA, oxalic acid and acetic acid, respectively. The amounts of Cr(?) extracted by citric acid, EDTA, oxalic acid and acetic acid increased by 439%, 244%, 215% and 162%.

Jan 1, 2009

By M. Götze, P. Eysel

Over the last years, the importance of the assessment of environmental and social aspects as well as of issues of good governance has increased significantly in mining finance. For this, international standards as well as internal guidelines of the banks and other involved institutions have been established and continuously improved. Considering these standards and regulations, the banks can influence the sustainability of mining projects - and they have done so in the past -, mainly by implementing certain provisions and covenants in the loan documentation, binding the financing to the mining company’s adherence to the agreed sustainability standards. However, there are limits to the banks’ influence due to the competitive environment with other available means of financing. Nevertheless, the experience of the last years has shown that the standards and regulations bound to the financing by the banks help to lead the mining industry towards more sustainable projects.

Jan 1, 2011

A comparatively new and very promIsmg field for applying cemented tungsten-carbides is in the mining and quarrying industries. The economic advantages of this unique engineering material over the conventional hollow drill steel, or steel detachable bits, have proven so great that the use of "hard metals" promises, in some instances, to revolutionise the drilling of all manner of minerals. Early in the war years the Germans realised the tremendous advantages cemented carbides offered for holing hard rocks, and they proceeded to develop detachable percussion bits to do this work, at the same time evolving fast, comparatively light-hitting driliing machines, especially designed to suit the mechanical properties of the carbide.Here in Australia also, it has appeared that the detachable percussion bit offers the greatest economic benefits to consumers, although the author is well aware that carbide-tipped drill rods have, and may continue to work out satisfactorily in certain mines and quarries.Most drilling equipment at present installed in Australia may be described as being of the heavy hard-hitting variety, so that the designer of an efficient percussion bit has to take special precautions to overcome the problem of fatigue, and to ensure that the inserts are securely mounted in the body with the minimum of internal stress in the carbide.

Jan 1, 1950

By Brian T. Burch, Paul N. Worsey

When fired, submerged Linear Shaped Charges (LSCs) lose all effectiveness in the cutting of steel. Users in underwater applications have reported having to substantially increase the charge size to the point where brute explosive force shears rather than cuts the target.

Jan 1, 2015

By V. Svalbonas, M. Fresko

The present versions of the Welding Codes, such as BS7608, have long been known to be compatible with hand computations of membrane and bending stress, rather than detailed finite element solutions. However, in the last five years, in the mining industry, this incompatibility has been largely ignored, and the code interpretations have been pushed into the realms of ground welds, residual stresses, and even flaw growth. Such techniques have to be recognized as extrapolations not necessarily sanctioned by the original code documents. The safety of such extrapolations, as they are related to grinding mill fatigue design, is investigated herein.

Jan 1, 2002

By T. Mwanza, B. N. Belford, P. Conradie

"Metix has introduced a three-piece ’deep-cooled’ copper slag tapblock into a six in-line copper matte settling electric furnace. The tapblock was designed without any internal refractory; it relies purely on the development and maintenance of a freeze lining on its hot face and within the tapping channel to protect the copper and promote the integrity of the surrounding endwall refractory lining. In addition, the geometry of the tapblock further supports the sidewall refractories, reduces the impact of funnelling and, therefore, the need for premature rebuilding of the furnace endwall, and facilitates easy removal and replacement of the wear components even under ’hot’ furnace conditions. Eighteen thermocouples embedded in the copper components ensure full resolution of the copper condition, enabling plant personnel to identify wear rates, estimate freeze lining thickness and stability, and schedule replacement of spares and wear components well in advance.At the time of writing the tapblock had been in operation for 6 months with approximately 350 000 t of slag having been tapped through it. Every indication is that the design will limit the need for premature relining of the furnace endwall due to rapid deterioration of the tapblock and its surrounding refractories. IntroductionNonferrous furnaces rely heavily on the maximization of refractory campaign life to increase profitability and reduce planned downtime. In large electric copper slag-cleaning furnaces utilizing insulating linings, campaign lives of six or more years are realistic if consideration is given to each aspect that can degrade the refractory lining during the campaign. An area that is particularly vulnerable is the slag tap-hole and the local surrounding refractory. To avoid premature relining of the furnace walls, every effort should be made to consider not only the tap-hole design itself, but also the selection of the sidewall refractory material and its construction immediately adjacent to the tap-hole, and furthermore the interplay between the tapblock and this adjacent refractory. A holistic approach to the design that considers these interdependent features in the slag tapping area can reduce the incidence of accelerated refractory wear (‘funnelling’), support the surrounding refractories to prevent their collapse, introduce easily replaceable wear components that can be exchanged with the furnace still ‘hot’, and encourage and maintain a stable freeze lining at the refractory hot face that maximizes the tapblock and refractory lifetime."

Jun 1, 2019

By Ralph B. S

Bacterial leaching of low grade quartz felspar porphyry copper ore was studied in large-scale laboratory percolation leaching columns.Limitations in the release of soluble copper showed up before fifty per cent recovery, due to occluding precipitates of iron oxides and hydroxides. Precipitates were removed by increasing the acidity of irrigation feed four-fold with respect to sulphuric acid. However, irrigation at low pH (pH 1.5) inhibited copper leaching. Resumption of bacterial leaching at pH2 was achieved by introducing a period of non-irrigation. The results suggest a 'direct' attack by bacteria on the chalcopyrite substrate rather than an 'indirect' ferric-leach mechanism.

Jan 1, 1981

By G Ma, L Qi, J G. Shellnutt

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Emeishan large igneous province (ELIP) of SW China is host to magmatic Ni–Cu–(PGE) sulfide and Fe–Ti–V oxide deposits which contain economic to subeconomic concentrations of precious and base metals. The formation of a given deposit-type (ie sulfide versus oxide) is thought to be related to the type of parental magma (ie high-Ti versus low-Ti) and the subsequent processes (ie fractional crystallisation and sulfide segregation), which allowed for metal enrichment.We examined the PGE of Baima and Taihe oxide-bearing layered mafic intrusions from the ELIP (Shellnutt, Ma and Qi, in press), and compared them with the nearby Xinjie and Hongge intrusions as well as with the Emeishan flood basalts. The PGE results for the two intrusions are contrasting. The Baima gabbroic rocks are almost PGE-barren (SPGE < 4 ppb) whereas the Taihe gabbroic rocks are variable, but generally much higher in PGE concentrations (SPGE < 2 to ~300 ppb), although the gabbros from both intrusions are enriched in platinum-subgroup PGE (PPGE = Rh, Pt and Pd) relative to iridium-subgroup PGE (IPGE = Os, Ir and Ru). Cu/Zr, Ni/Ir, Y/Pt, Cu/Pd and Ni/Ir systematics suggest that the Baima rocks were derived from a relatively evolved, mafic, S-undersaturated parental magma that was affected by earlier sulfide segregation. In contrast, the Taihe rocks record evidence of both S-saturated and S-undersaturated conditions and that the parental magma was likely emplaced very close to S-saturation. Through comparison of the PGE contents in the Emeishan flood basalts and the Emeishan oxide-bearing intrusions, we provide a self-consistent model for ELIP that the PGE budget in a magma is not strictly controlled by magma series (high-Ti versus low-Ti), but very much by crustal contamination.CITATION:Ma, G, Shellnutt, J G and Qi, L, 2015. Platinum group elements in the Baima and Taihe Fe-Ti oxide-bearing gabbroic intrusions of emeishan large igneous province and problems on propensity of magma series for sulfide- versus oxide-dominated deposit types, in Proceedings PACRIM 2015 Congress, pp 303–310 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Tobias Hansson

The quality of Lime Cement (L/C) columns is to a great extent dependent on the installation procedure. At a site in the south of Sweden, the client reported problems with the installed columns. To evaluate the operator and equipment dependent part of the installation, Hercules Grundläggning AB was appointed as a competitor to the site contractor. The purpose was to install a number of L/C columns with equal installation parameters for both contractors. A total of 65 test columns were installed in June 1999. The geology is a typical Swedish organic soil profile with a top layer of peat overlying gyttja and clay. Two different binders were used in the comparison; blast furnace slag with cement and lime with cement. After installation, the quality of the columns was monitored by penetration tests and a column sampler for extracting whole columns. The column penetration test were performed 28 and 134 days after installation and extraction 134 days after installation. Inspection and tests of the extracted columns showed that by using a fully computer controlled procedure, the contractor produces columns of superior quality and homogeneity.

Jan 1, 2000

By Sie A

After completing a feasibility study in 1987, Niugini Mining Limited (NML) obtained five Gold Mining Leases within PA 632, covering the Mount Victor and Clarkes Ridge gold deposits. Reserves prior to mining were 260 000t at 3.63g/t Au for Mount Victor and 40 000t at 2.8g/t Au for Clarkes Ridge. Ore was mined from the two deposits by NML from November 1987 to January 1990. A total of 645kg of gold and 346kg of silver were produced from 198 000 tonnes of ore pro- cessed. Mining and milling operations ceased in February 1990. Since then, there has been significant progress in rehabilitating and revegetating the site. Plant and workshop facilities have been dismantled and removed from site, exposed parts of the pit have been landscaped and replanted, tailings water has been neutralised and discharged, and the dam filled. All remaining personnel and equipment left the site in November 1990. It is envisaged that the replanted areas will be rapidly revegetated, leaving little evidence of mining. Niugini Mining did not recoup the initial investment for Mount Victor, but the mine produced a positive cash flow and made a significant' financial contribution to the local communities and Papua New Guinea as a Whole.

Jan 1, 1991

The Bagdad mill, built in 1977, was de-signed for a mill capacity of 36,300 tpd. An ABC (Autogenous Mill-Ball Mill-Crusher) grinding circuit was chosen. The original mill contained three completely independent grinding circuits, each containing one 9.75 m diameter by 3.96 m long fixed speed autogenous mill, one 4.72 m diameter by 6.71 m long ball mill and one 2.13 m diameter short-head cone crusher. Total installed power per grinding circuit was 8,464 kw with 5,966 kw in the autogenous mill, 2,237 kw in the ball mill and 261 kw in the crusher. (See FIGURE I--Major Equipment Flow Diagram.) The autogenous mills were designed to be able to operate semi-autogenously but were never converted to SAG. As a result of this design, only about 4,100 kw of the designed power is utilized in the autogenous mills. The grinding circuits are closed with 2.44 m by 6.10 m double deck vibrating screens. Screen oversize is returned, by a series of conveyors, underneath the mill coarse ore stockpile to feed the crushers. Variable speed belts feed the crushers and control power draw. Crusher product reports directly to the tail end of the autogenous mill feed belt. (See FIGURE 2--Typical Crusher Feed and Product Size Distributions.) Tramp iron in the autogenous mill-crusher circuit is handled in a unique way. A magnetic sensor detects the metal. This closes a gate which directs the crusher feed onto a separate belt which bypasses the crusher and returns the material to the autogenous mill feed belt.

Jan 1, 1992

By L. C. Marchant

Results of detailed analyses of four cores from the Threemile Canyon area in the P. R. Spring tar sand deposit in Utah are reported by the Bureau of Mines. The cores were obtained by the Utah Geological and Mineralogical Sur-vey as part of a l7-corehole evaluation program in the P. R. Spring, Hill Creek, and Rim Rock tar sand deposits. Average properties of the oil zone in the Threemile Canyon area as deter-mined from these cores are as follows: Oil saturation, 67.4 pet of pore volume; porosity, 29.2 pct; permeability before oil extraction, 133 millidarcies; and permeability after oil extraction, 2,855 millidarcies. Average net thickness of the oil zone is 23.8 ft and average depth to the top of the oil zone is 189 ft.

Jan 1, 1974

Arizona FRANK A. WARDLAW, JR., Chairman GRANT R. RUBLY, Secretary-Treasurer Miami Copper Co., Box 505, Miami, Ariz. MICHAEL CURLEY C. R. KUZELL BURRELL R. HATCHER A. MENDELSOHN WILLIAM KOERNERA. C. REIFSNIDER Black Hills L. B. EAMES, Chairman ALEXANDER J. M. Ross, First Vice-Chairman FRANCIS CHURCH LINCOLN, Second Vice-Chairman NATHANIEL HERZ, Secretary-Treasurer Lead, S. D. JOSEPH P. CONNOLLY C. N. KRAVIG C. E. DAWSON EDWARD L. TULLIS

Jan 1, 1939

By D. R. Lentz, C. J. Beaumont-Smith, S. H. Mcclenaghan

"Abstract - The Louvicourt Au-Ag-Cu-Zn-Pb sulfide deposit is hosted by a Middle Ordovician calc-alkaline sequence of aphyric rhyolite flows and associated fragmental rocks at the top of the Flat Landing Brook Formation. The Zr/TiO2 (average = 0.110) and Y/TiO2 (average = 0.021) ratios in the footwall felsic volcanic rocks are consistent with known values for the Reids Brook member. The deposit consists of two concordant lenses of semi-massive to massive sulfides, approximately 150 m long and up to 9 m thick, which represent a fold repetition of a single exhalative horizon. The deposit contains a geologic resource of 136 000 tonnes grading 1.2% Pb, 1.0% Zn, 0.4% Cu, 90.9 g/t Ag, and 0.96 g/t Au; the deposit locally contains elevated Au (2.9 ppm) and Ag (320 ppm) contents. A laterally continuous iron formation that contains barite caps the deposit, and is gradational vertically and laterally into laminated siltstone. The exhalite confirms the stratiform nature of this deposit, but a large percentage of sulfides occur as late replacements of altered felsic fragmental rocks in the footwall. Abundant examples of colloform pyrite and perlitic and spherulitic textures in volcanic clasts are well preserved. The base- and precious-metal content of the Louvicourt deposit is atypical of the Bathurst Mining Camp (BMC). Reported assay data (n = 27) indicate an average Pb/Zn ratio of 2.6, the highest in the BMC (average = 0.39). Lead exhibits a strong Spearman Rank correlation (r' = 0.92) with base metals throughout the sequence, indicating a preponderance of galena in both the stockwork and stratiform zones. The Ag and Au contents in this deposit are among the highest in the BMC and exhibit a Au-Ag- Cu-Pb association. Barite-rich exhalative pyrite exhibits a moderate Au correlation with Ag (r' = 0.77; n = 10) and Cu (r' = 0.76) and occurs in portions of the exhalative sulfides that are enriched in Pb. Chemical exhalative rocks are conformably overlain by trachy-andesitic volcaniclastic (possibly pyroclastic) rocks that are assigned to the Little River Formation. These are enriched in Nb (average = 38.4 ppm) and P2O5 (average = 0.17 wt.%), and have much lower Zr/TiO2 (average = 0.056) and Y/TiO2 (average = 0.0062) relative to rocks higher in the hanging wall. The intermediate volcanic rocks are conformably overlain by massive to pillowed basalt flows and related hyaloclastite that have Nb/Y = 0.60 and high TiO2 contents (average = 2.8 wt.%). This chemistry is consistent with rocks of the Brunswick Mines member (Little River Formation), except that these rocks are considerably enriched in P2O5 (average = 0.82 wt.%). This syngenetic exhalative deposit is unique for the BMC with a high Pb/Zn and elevated Au and Ag contents, as well as an epithermal signature (Sb-Ag-Au-Tl-Hg), analogous to high sulfidation volcanogenic massive sulfide deposits. Its intimate relationship with an emergent felsic dome (Flat Landing Brook Formation), chlorite-silicate-oxide-sulfide exhalite (locally hematitic), and the abundance of barite are classical features of many of the Kuroko deposits."

Jan 1, 2006

By M. A. Meyer

Underground mining accidents in the USA in recent times have prompted the Mine Safety and Health Administration (MSHA) to review emergency and tracking systems for underground mines. Several communication and tracking systems are available on the market and various systems have been installed in mines around the world. In addition, MSHA?s standard on Diesel Particulate Matter (DPM) requires mines to comply with the final PEL of 160µg/m3 by May 20, 2008. Barrick Goldstrike Mines Inc., Underground Division, has been in operation since 1995 and an extensive control and monitoring network, and a leaky feeder voice network is in place. Enhancements to the communication and control system are currently being implemented to include a PED emergency notification system, wireless LAN with tracking of personnel and equipment in the mine, and a ventilation control system that will use the tracking information and ventilation data to automate much of the mine ventilation system. Expected benefits from such a system would be enhanced communication with miners, emergency notification, location of miners and equipment, energy savings, improved ventilation control, and improved atmospheric conditions in the mine including reduction of diesel particulate matter (DPM).

Jan 1, 2009

By Roger B. Alke

INTRODUCTION Request to Mine Beneath Bridge The Jakes Run Bridge is a reinforced Portland concrete arch filled bridge located on WV Route 7 near Pentress, WV. The bridge has a span of 22.9 m (meters) and a height of 4 m above normal pool elevation to the underside of the center of the arch (See Fig 1). The bridge is a two lane structure with a width of 6.86 m. The structure is over 50 years old having been built in 1929 and is owned by the Department (WV Department of Highways). [ ]

Jan 1, 1984