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Continuing with the effort of providing new and more effective exploration methods to the mining industry, where direct methods (drilling, cross-cutting, etc.) are not applicable, either for logistical or environmental reasons or because they are costly and sometimes ineffective, we present here a new seismic technique based on full wave recording of 3-D channel waves generated within the coal seam across a longwall. In the past two years we reported the application on In-Seam High Resolution Seismic Reflection (ISHRSR) and In-Seam Seismic Tomography (ISST) to map non-coal inclusions that disrupt the coal seam continuity. In the present paper we present a 3-D In-Seam Seismic Tomography (3-DTSST) method using 3-D channel waves recorded by three component high resolution geophones. The method allows to distinguish longitudinal and transversal components of the channel waves, similar to the spheroidal and toroidal modes for the free oscillations of the earth. The recording of these waves allows a more complete analysis of the free modal vibrations of channel waves, permitting a more complete inversion of the structure of the coal seam through which they travel. The full wave analysis provides additional insights of the detailed coal structure for larger, distances than for the ones previously reported using the one dimensional method. The refinement of the inversion software is also a contribution towards the better definition of the coal seam geometry and structures disturbing them such as sandstone channels, sandstone rolls, partings, mine voids, faults, fractures, etc. The method is illustrated with three case studies where subsequent mining revealed the virtues and limitations. The first example deals with the problem of mapping mine works in one side of a longwall panel which geometry is well known, to verify its applicability to map old mine works. The second example deals with a sandstone body that partially scoured the coal seam withing a longwall panel. The third shows an application of the method to map roof conditions in a longwall panel where this problem critically affected production scheduling and costs

Jan 1, 1996

By C T. Hollick

Conventional processing of heavy mineral deposits containing radioactive rare earth minerals such as monazite and xenotime may cause industrial hygiene problems through atmospheric dust and contamination of product concentrates. An alternative procedure has been developed in which such minerals are removed from bulk heavy mineral concentrates by flotation with little loss of other economic minerals. With fine ores, recoveries of over 95 per cent have been achieved and with coarse ores over 80 per cent, in both cases at high grade. Several flotation regimes have proven effective. The potential for generation of radioactive dust or product contamination is subsequent processing is correspondingly reduced.

Jan 1, 1990

The University of New South Wales (UNSW Australia) has been a world leader in the development of innovative virtual reality technologies over the last 15 years. AVIE (Advanced Visualisation and Interactive Environment) was developed by iCinema as a collaborative venture between UNSW?s Faculties of Engineering and the College of Fine Arts. This is the world?s first 360°-surround, virtual reality (VR) stereo projection theatre system. The School of Mining Engineering at UNSW Australia has developed 18 different virtual reality modules aimed at mine safety training and mining engineering education. These modules are being regularly used in both the mining industry and the university. The School of Mining Engineering is continuously involved in the development of different modules. Research is also currently being conducted on the implementation of other technologies into this environment. Artificial intelligence (AI) and fuzzy logic are tools that the authors would like to consider implementing in future module development. This paper will review current research in both these areas and consider options for applying these technologies.

Jan 1, 2014

By R. N. Powell

The Pipeline ore body was discovered in March 1991. The construction of the new mine and mill did not start until early March of 1996. Upon completion of permitting and corporate project approval, the 289 million USD project was “fast tracked”. The commissioning began 11 months after start of construction and the project ended 40 million USD under the budget figure. The objective of this paper is to review and highlight the Pipeline Project history from discovery, design, lawsuits, permitting, and re-design through to current - 1998operating practices. Particular emphasis will review the process design, design mistakes, and design successes. The paper will review project history, feasibility, design concepts, operator training, construction, financial and the current operation. Additional discussion will review what design features worked and which did not work within the process plant.

Jan 1, 1999

By Sandeep Kumar Jeripotula, Govinda Raj Mandela, Aruna Manglapady

Dumper operators are frequently exposed to whole body vibration (WBV) in surface mines. Surface mining activities involve the amalgamation of comparatively high intensity of vibration and extended exposure durations. Efficient risk reduction mandates knowing of important phases of a task that poses a threat to health of dumper operators. So far in India very limited studies have been reported on WBV exposure with regard to surface mines. This paper evaluates WBV of dumper operators based on ISO 2631-1:1997 Standards and European Union (EU) Directive 2002 for different phases of job cycle. Six dumpers were considered for this study and the vibration measurements were made for all the four phases of the job cycle by placing the triaxial accelerometer on the operator’s seat-surface and at the seat-back, independently. The findings of the study revealed that the haulage task (loaded travel and empty travel) remains the chief contributor to vibration exposure according to seat-surface and seat-back measurements. Maximum frequency weighted root mean square (RMS) of 1.12 m/s2 and 1.09 m/s2 were reported for empty travel task for seat-surface and seat-back measurements, respectively. For seat-surface measurements based on RMS, Z axis remains as the dominant axis of vibration for all the dumpers during haulage task, whereas for seat-back measurements, the dominant axis varies between X and Y. Exposure action value (EAV) based on RMS has exceeded the threshold value of 0.5 m/s2 for all the dumpers during loaded travel and empty travel for seat-surface as well as for seat-back measurements.

By Gregg A. Scott, Gordon F. Revey

"The Folsom Dam is a 340-foot-high concrete gravity dam with embankment wing dams located on the American River about 20 miles northeast of Sacramento, California. Folsom Dam is operated andmaintained by the U. S. Bureau of Reclamation (Reclamation). As part of the Central Valley Project,Folsom Dam is a multipurpose facility providing water supply storage, flood control, power generation, and recreational opportunities."

Jan 1, 1999

By Richard J. Mainiero, Michael J. Sapko, Marcia L. Harris

Since 1988, there have been thirteen documented incidents in the United States and Canada in which carbon monoxide (CO) is suspected to have migrated through near surface strata into structures or other enclosed spaces as a result of nearby trench blasting or surface mine blasting. From these incidents, there are thirty suspected or medically verified CO poisonings and one fatality associated with these incidents. To better understand the variables contributing to this hazard, the National Institute for Occupational Safety and Health (NIOSH) carried out a small- scale field study to identify key factors that may contribute to the migration of CO through the ground. NIOSH conducted single- hole heavily confined experimental test shots to measure the radial pressure pulse as it propagated through surrounding monitoring holes to determine if a relationship existed between the pressure pulse and resulting CO measurements afterwards. NIOSH also monitored blasts at an airport construction site. Following the detonations, the concentrations of CO, nitric oxide (NO), and nitrogen dioxide (NO2) were monitored for several days in the surrounding satellite holes. The peak CO measurements relative to distances from the shots were compared. Pressure histories and peak particle velocities (PPV) were measured at monitoring boreholes. It was found that the differential pressures recorded within the boreholes give some indication as to the likelihood of CO appearing, whereas the PPV measurements do not seem to be as good an indicator for potential CO migration. In this limited study, changes in barometric pressure had very little influence on removing the trapped detonation products, whereas applying a vacuum to the monitoring holes was effective in reducing the entrapped CO concentration.

Jan 1, 2005

By Brandon Fryman, Josh Hoffman, Rhys Baker

A post-detonation debris collection project was led in conjunction with a large ammonium nitrate(AN) railcar detonation conducted by the Department of Homeland Security-Transportation Security Administration, Department of Defense-Combating Terrorism Technical Support Office, Sandia National Laboratories, and the U.S. Army Dugway Proving Grounds. This important work will aid in underpinning algorithms used in a Quantitative Risk Assessment (QRA) tool. The test also provided valuable data about the effects and consequences following an AN detonation. The test took place at the Utah Dugway Proving Grounds on April 27, 2018 and the debris collection was conducted the following two weeks with an average of 20 persons per day and an approximate total of 1,400 manhours. A paper was presented at the 2019 ISEE Conference on the collection efforts, challenges, and lessons learned. A complete data analysis effort was completed on the test data in 2019 that resulted in updates to the QRA Railcar Potential Explosion Site (PES)model and AN engine. The analysis included an assessment of the debris data resulting from the Derailed test. This paper is meant to serve as a summary of the analysis effort and findings and as an update to the previously presented lessons learned from the debris collection and analysis effort.

By F. F. Peng

The raw-coal feeding system and the upward medium current flow in a dense-medium vessel (DMV) are, in addition to the residence time of particles in the separator, important factors for efficient coarse particle separation. The feed material from a raw coal screen and/or pre-wet screen merge with the major volume of circulating medium as push medium, guided by an adjustable submergence baffle plate deep fed into the separator for effective separation. The remaining volume of the circulating medium enters from the purge and drain hoppers at the bottom of the DMV. This generates a gentle upward medium current flow in the separator, which prevents dense medium stratification/settling and merges as part of the push medium. A two-dimensional, two-phase model developed using computational fluid dynamics (CFD) is used to describe the flow pattern and evaluate the function of the dip plate for understanding the mechanisms of particle separation in the separator. The particle movement in the DMV is also tracked to investigate the major operating parameters affecting the separation performance of the DMV. The simulation results of the DMV separation performance are validated by in-plant test data.

Jan 1, 2007

By Johnna Muinonen

"The Thompson Mill processes ores from the Thompson and Birchtree Mines. While the Thompson ore has very little magnesium containing gangue, the Birchtree orebody consists of veins of massive sulphide in a rock matrix that contains a high proportion of magnesium silicate minerals. A significant fraction of the magnesium is floatable, which lead to MgO levels varying from 3-11 wt% in the Birchtree concentrate. The magnesium in the concentrate causes a higher operating temperature in the smelter, reducing furnace life.Birchtree ore represented 20-30% of the mill ore receipts prior to October 2003. Since then the fraction of Birchtree ore has increased to 50%. A reduction of the MgO in concentrate to less than 3% in the total mill concentrate was required to allow safe and economic smelter operation.In October of 2002 a miniplant was set up to simulate the Birchtree plant circuit. Several flow sheet modifications were tested that led to a proposal for a circuit having increased cleaning capacity for the scavenger concentrate and a recleaner on this concentrate. Addition of CMC in rougher cleaner feed was also found to be required. The solution was confirmed through pilot plant testing in the mill in December of 2002. A full-scale installation was designed, engineered, and installed between February and September of 2003 with commissioning in September and October of 2003. Target metallurgy was achieved one week after start-up on slurry to coincide with the Birchtree Mine tonnage increase. This paper highlights the development, design and commissioning stages of the project.The new MgO rejection circuit has successfully allowed the processing of Birchtree ores producing concentrate consistently below 3% MgO. In addition, the new circuit increased overall nickel recovery in the mill.INTRODUCTIONThe Thompson Nickel Belt located approximately 700km north of Winnipeg was discovered in the early 1950’s. Inco first produced nickel from the area in 1960. Over the years the mill has processed several ores from different ore bodies in the area. Currently the Thompson Mill processes two significantly different ores from two mines, Thompson and Birchtree. The Thompson ore is a massive sulphide orebody hosted in schist, containing feldspars, quartz and biotite. Thompson Ore is characterized by high nickel recoveries and clean, low MgO containing concentrates (<2.5% MgO). The Birchtree ore is ultramafic and contains a high percentage of Mg-silicates such as serpentine, chlorite, biotite, amphiboles and talc. Some of these Mg-silicates report to the nickel concentrate and prior to commissioning of the MgO rejection circuit the Birchtree nickel concentrate typically contained 5-8% MgO"

Jan 1, 2006

By Edmonds W, Jeffcoat R

The completion of the first two open hearth furnaces in the new No. 2 open hearth plant at Port Kembla will increase Australian production of steel by 350,000 tons of ingots per annum.The paper gives an outline of the essential features of open hearth design and auxiliary equipment required to operate the two modern open hearth furnaces at present being installed.INTRODUCTIONThe increasing demand for steel required by Australian secondary industries led to the decision to construct and operate No. 2 open hearth plant at Port Kembla. Two basic open hearth furnaces of the most modern design are under construction and it is anticipated that these units will be commissi.oned in September 1956. Australian steel capacity will thereby be increased by approximately 350,000 tons of ingots per annum.PLANT LAY-OUT AND CONSTRUCTIONIn the design and lay-out of this plant the emphasis has been on efficient material handling with simplicity of design and operation. Overseas methods were studied and these studies, together with experience gained at Newcastle and Port Kembla open hearth shops, enabled this plant to be built to a standard which compares favourably with any other in the industry.Initially two furnaces, each of 2,75 tons capacity, have been built, but provision has been made in. the design and lay-out to enable expansion to six furnaces.The location of the new plant in relation to the existing units will be noted in Fig. 5. It is one of the first units to be built in an area which will dovetail into a pattern for...

Jan 1, 1957

Laboratory induced polarization measurements were made on representative samples of concentrated sulphide ores from three environments in New South Wales Comparisons were made with the membrane polarization exhibited by an argillaceous sandstone. The sulphide samples showed a strong polarization effect, the magmtude of whIch depended directly on the conductivity of tlIe pore electrolyte.

Jan 1, 1969

By Tomás Gonzáles

El presente trabajo describe la metodología usada para evaluar las estrategias de las alternativas del planeamiento a largo plazo en la explotación del mineral y el lixiviable en la Mina Toquepala.

Aug 25, 2002

By F. W. Horton

This paper covers the salient features of the occurrence and mining of sheet mica in the United States and the preparation of mica for market; presents the results of a study of the physical properties of domestic and foreign micas, which the author hopes may he of interest to every mica user, as it definitely answers many questions as to the suitability of various minas for particular purposes; and discusses mica-trade conditions and the future outlook for the domestic mica industry. ACKNOWLEDGMENTS The author takes pleasure in acknowledging his indebtedness to J. R. Thoenen, of the United Stator Bureau of Mines, under whose guidance the work reported herein was performed, and to Frank L. Hess, also of the Bureau, for information on the geological and mineralogical characteristics of mica-bearing pegmatites.

Jan 1, 1935

By I. W. van der Merwe

Recently, a new kind of filtration has emerged, namely nano-filtration (NF). It is a membrane-based process which exhibits totally unique separation characteristics for dissolved salts as well as for many non-charged species. By exploiting the particular separation characteristics of this new membrane type, many unique and novel separations have been made possible. The basis for separation by nanofiltration is the negative surface charge of the membrane. This results in rejection of multivalent anions, whilst associated cations are also rejected to maintain electro-neutrality. This peculiar property enables separation of dissolved ions such as sulphate and copper from acid, whilst the acid may be purified for reuse. This paper aims at providing an overview of the principles of nanofiltration, illustrated by particular examples.

Jan 1, 1998

By Don K. Smith

The Reclamation Program for the Northern Zone of the Indus Plains in West Pakistan involves the construction of 30,000 irrigation wells to serve 20 million acres with an annual pumpage of nearly 40 million acre-ft. Detailed hydrologic studies indicated that mild steel would be satisfactory for casing; however, within two years after construction, about 10% of the wells began to fail due to encrustation and corrosion of the casing. A search to find a noncor-rosive substitute for the steel casing disclosed that only fiberglass-reinforced plastic pipe satisfied all requirements. The results of initial use of fiberglass have been highly satisfactory and have resulted in a lower over-all well cost. Advances in technology pomise further reduction in prices and improvement in performance. The northern zone of the Indus Basin comprises a vast area of essentially level land in West Pakistan which is irrigated by means of a complex system of canals that distribute more water to more land than any other irrigation system in the world. In spite of the development of this extensive irrigation system, production of food and fiber has not met the requirements of the country. The major reasons that crop production has not reached anticipated levels are the lack of adequate irrigation supplies and effective subsurface drainage. As a result, yields per acre are among the lowest in the world for areas where irrigation is practiced, and many thousands of acres of valuable crop land have been removed from production or seriously affected by salinity and waterlogging. To rectify the problems of irrigation supply and drainage the Government of Pakistan has undertaken a program of Salinity Control and Reclamation which is being administered by the Water and Power Development Authority. The Authority retained Tipton and Kalmbach, Inc., of Denver, Colo., as engineers for the program in the northern zone of the Indus Basin. This program consists of the construction of about 30,000 irrigation wells to provide drainage for waterlogged lands and full irrigation supplies, including leaching requirements, for all cultivated lands. The program will ultimately ensure the productivity of 20 million acres and involve an annual pumpage from groundwater storage of nearly 40 million acre-ft of

Jan 1, 1970

By R. B. Alke

Request to Mine Beneath Bridge The Jabs Run Bridge is a reinforced portland concrete arch filled bridge located on WV Bouts 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 Pig 1). The bridge is a two lane structure with a width of 6.86 m. The structure is over 50 years old Wing been built in 1929 and is owned by the Department (WV Department of Highways).

Jan 1, 1984

NATURE OF ORETHE Edna May ore consists mainly of clean quartz of a moderately hard and tough nature. The gold content is &quot;free&quot; and fairly coarse, so that a large percentage is recovered by amalgamation. The ore is practically free from metallic minerals.GENERAL OUTLINE OF PLANT AND TREATMENTThe ore, received from underground in trucks, is broken by a jaw breaker, then stamp-milled, follow~d by partial filie-grinding in pans. Mercury is used both in the mill boxes and pans. The pulp, on leaving the pans, passes over amalgamating tables and is then elevated by tailings pulp to cone classifiers and separated into a sand and slime product, each product receiving a separate cyanide treatment-sand by leaching in vats and slime by agitation and decantation in a &quot;Trent&quot; plant. Gold solutions from both sand and slime are precipitated together by zinc shavings in the usual type of precipitation boxes. Accumulated slime is trucked from the dam to a vortex mixer and from this point receives with the cement slime the same treatment.ORE BREAKING AND TRANSPORTThe ore is trucked from the brace of the shaft along an overhead line to the breaker station. Hence it is, by means of a &quot;kick-up&quot; dumped upon a grizzly, set with 2-in. spaces, the oversize being broken by a 15 x &apos;9 Fraser and Chalmer jaw...

Jan 1, 1919

By James F. Kvitkovich, George V. Weisdack

Editor’s note: This is the second part of a two-part series on longwall mining in the United States. Part one was published in the December 2005 issue of ME (pp. 21-26). It provided a history of longwall coal mining in the United States. It also discussed the technology involved in the productivity gains and operational improvements. Boyd anticipates that U.S. coal production will increase by 61 Mt (67 million st) (6 percent) from 2004 to 2010. A combination of higher surface and underground mine production will be required to meet the projected market demand. Boyd’s projections of coal production by major mining methods are shown in Table 1.

Jan 1, 2006

By Penrose E. K

With the exception of occasional periods, when up to 80% of oxidized ore was treated, the G.M.K. plant treated all sulphide ore until October, 1939. The treatment was, briefly, as follows:The ore was ground to approximately 17% plus 200 mesh Tyler and agitated in cyanide solution, after straking. After agitation, the pulp passed through two stages of counter-current decantation washing in Dorr thickeners and was filtered once, to complete the precyanidation stage.The precyanide filter cake was repulped with flotation circuit solution and floated in a Denver Sub A flotation machine, consisting of twelve cells. The concentrates were roasted, cyanided and filtered four times before disposal to the&apos; dam. The flotation tailings were thickened to conserve water and pumped away to a separate dam.The average results of flotation operations for the six months before October, 1939, are shown in Table 1.

Jan 1, 1942