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By Loren R. Anderson

This is an Appendix of Volume I. In contains the results of the electric cone penetrometer soundings from the second phase of the testing program.

Jan 1, 1982

By B. Cousins

Flotation reagents are critical to the optimum performance of flotation circuits. How a flotation reagent performs within the first few cells of a flotation train is a key indicator of how well it will perform throughout the entire circuit. A method to compare reagent performance was recently developed by Ashland Water Technologies. The procedure involves collecting a timed sample of concentrate from each cell and then measuring the volume of the settled solids. An estimate of the percentage of concentrate collected from each cell can then be mathematically determined, providing an understanding of the recovery changes in each cell. Data from trials at a coal flotation circuit are used to demonstrate the method's validity.

Feb 27, 2013

By Kurt R. P Petersen

This paper discusses the current approaches to modelling the DMS cyclone within the De Beers group. Current efforts are split into short term value-adding process understanding and longer term semi-fundamental analysis of separation mechanisms. To date, the basic applied approach has yielded significant value to the group, enabling operators to focus on simple diagnostic measures to control their process. The more involved modelling approach has given rise to a new understanding of the separation field, in particular that the high density gradients within a cyclone are highly localised, indicating that separation of medium to heavy density material takes place low in the cone. The model has proven to be conceptually robust, but still requires further development and validation to become a complete modelling and simulation tool for De Beers.

Jan 1, 2006

By Suresh Menon

The explosive industry in India has passed through various stages - from a period of total dependency to a period of self sufficiency and now, is saddled with large spare capacity. The last decade and a half saw the emergence of small scale manufacturers, which until then was thriving on International technology.

Jan 1, 1998

By J M. Marwan, B Tang

Strain-type rockbursts, or strainbursts, are characterised by a localised violent failure. Their cause is attributed primarily to the sudden release of strain energy, which accumulates in a volume of highly stressed rock as a result of mining activities. Examples of such phenomena are crown/sill pillar bursts created in the mining process, pillar crush in room-and-pillar mining, face ejection in drift development headings at depth, and floor bursts associated with deep shaft sinking. The paper describes a simple method for the assessment of crown pillar bursts in steeply dipping ore deposits which are extracted by the overhand cut-and-fill method. The method is based on a theory previously established by the author to help assess the need for a remedial solution such as pillar destress blasting. Basically, the mining-induced energy storage rate (ESR) in the pillar is compared with the critical strain energy to come up with the so-called burst potential index (BPI).

Jan 1, 2001

By Bryan R. Carmenati

This report documents the need for formal health and safety, and equipment operations training in the mine construction industry. The outlines, objectives, and training texts were developed based on the recommendation of needs of mine construction personnel, and those of Dames and Moore (Safety Analysis of Shaft Sinking operations, 1977) and Kinton, Inc. (A Training Program for Conventional and Raise Drill Construction Personnel; Phase I, 1979). The training material samples contained herein (and under separate cover in its entirety) are designed to improve the safety and production of those in mine construction. An instructor-directed presentation is recommended. The results of the study are presented in the Findings and Recommendations section of this report.

Jan 1, 1982

Optimisation of the Performance of Flotation Circuits Using a Genetic Algorithm Oriented by Process-Based Rules

Sep 13, 2010

By Janine Pierce, Robert Larson, Christine Raasch

The vibration and impact environment for crew members on locomotives has been investigated in a series of studies conducted by Exponent Failure Analysis Associates (Exponent) beginning in 1990. Locomotive cab vibration and impact levels were measured on a variety of locomotive models operating over many different track sections across the Union Pacific, Burlington Northern Santa Fe, CSX, Norfolk Southern, and CONRAIL systems. The comfort and health implications of exposure to the measured locomotive vibration levels were evaluated by comparison with the human vibration exposure boundaries given in the International Standards Organization (ISO) standard 2631-1:1997, the British Standard 6841:1987, European Union (EU) Directive 2002/44/EC, measurements made by Exponent on various commercial and recreational vehicles, and vibration exposure measurement data found in the literature. Methods Initially, vibration levels experienced by locomotive crews were measured and recorded at incremental speeds covering the range of normal train operation. In 2003, a method of measuring the vibration exposure continuously by means of a digital recorder was developed, allowing the vibration level over the entire run or crew shift to be analyzed. For each seating location measured, acceleration was recorded on the seat surface beneath the ischial tuberosities (pelvis) of the seated crew member and on the cab floor directly under the seat. At each of the locations, triaxial accelerometers were used to measure the vibration along the longitudinal, lateral, and vertical axes. Since the vibration environment varies throughout the route, and locomotive vibration levels have been found to be primarily speed dependent, a speed sensor was used to continuously measure the speed of the train. To evaluate the recorded vibrations levels, the data was divided into two-minute segments, which were each processed per the 1997 ISO standard for weighted RMS vibration levels and Vibration Dose Values (VDV). Additionally, PSDs and 1/3 Octave RMS values were calculated to determine the frequency content of the vibration. For each two-minute segment, the average speed of the locomotive was calculated to allow for correlation with the recorded vibration exposure values. The resulting exposure values for the entire run were calculated by combining the data from all of the two-minute segments. Since introducing the continuous method of recording acceleration, 23 seating locations have been recorded on 11 locomotives traveling 11 different routes across various parts of the United States. One of the routes was a shift of ‘yard work’, traveling back and forth in a rail yard coupling train cars together. Results A guide to interpreting weighted acceleration values with respect to health is given in Annex B of the 1997 ISO standard. A health guidance caution zone is defined to indicate the

Jan 6, 2006

Cyclonic Separation Effect of Metallic Ores in Cyclonic-Static Micro-Bubble Flotation Column

Sep 13, 2010

By J S-L Chan

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. Cu-Ag-Au mineralisation at Kluwih prospect in Eastern Java, Indonesia is related to a high-sulfidation hydrothermal system within a volcanic dome (2.35 × 1.7 km diameter). The mineralisation occurs mainly in steeply dipping, structurally-controlled quartz-enargite-pyrite veins (several centimetres to 2 m wide) and is hosted mainly in porphyritic dacite, volcaniclastic rocks and volcanic breccia of the dome and in an underlying andesite that yielded a zircon U-Pb age of 11.5 Ma.Short wave infrared spectrometer analyses were carried out for alteration mapping at Kluwih. There are two main stages of alteration produced by the hydrothermal activity. The alteration mineral assemblages indicate an advanced argillic alteration. The Cu mineralisation occurred in the form of enargite and subordinate chalcopyrite with an intergrown texture in the early stage. These mineralised veins are characterised by narrow pyrophyllite ± diaspore and dickite selvages (metres wide) and a peripheral K-muscovite envelope (sericitic alteration) up to 100 m wide. The K-muscovite envelope is zoned outward to Na-muscovite or Na-illite. Late-stage kaolinite and smectite alteration overprints the porphyritic dacite and may obscure the nature of early mica-clay alteration. The spatial distribution of different alteration assemblages suggests that the temperature of hydrothermal fluid increases with depth.Both the high-sulfidation mineralisation and advanced argillic alteration are suggested to be related to magmatic-hydrothermal fluids, which are likely to originate from an undiscovered deeper porphyry Cu-Au system below the porphyritic dacite. Based on alteration mapping results and comparisons to similar deposits, the porphyry intrusion could be up to 500 m below the volcanic dome. Further geochemical and mineralogical studies may help to target the potential underlying porphyry system.CITATION:Chan, J S-L, 2015. High-sulfidation epithermal Cu-Ag-Au deposit, Kluwih, eastern Java, Indonesia – alteration and implications for potential porphyry cu mineralisation, in Proceedings PACRIM 2015 Congress, pp 213–218 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By H Chen

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Mesozoic iron oxide-copper-gold (IOCG) mineralisation in southern Perú and the northern Chile coastal IOCG belt have emerged as two of the major exploration targets in the Central Andes in the last two decades. These Mesozoic Andean IOCG deposits formed in two mineralisation epochs, the Middle-Late Jurassic (170–150 Ma) and Early Cretaceous (130–110 Ma), with the major Cu-rich IOCG deposits located in the Early Cretaceous mineralisation belt. The early studies in some IOCG centres support a magmtic-hydrothermal model for both Cu-rich IOCG deposits and broadly contemporaneous Cu-poor ‘Kiruna-type’ magnetite deposits. However, recent evidence from field, geochronology, fluid inclusions and stable isotopes show that in the major Central Andean deposits (eg Raúl-Condestable, Mina Justa in southern Perú, La Candelaria-Punta del Cobre and Mantoverde in northern Chile), the incursion of evaporite-sourced basinal brines or sea water may be a prerequisite for economic Cu mineralisation. Moreover, the Cu-poor massive magnetite deposits could be interpreted as a product from iron oxide melt, with minimal intervention by non-magmatic fluids. Therefore, they could represent two contrasted deposit types and contain little genetic relationships. The different roles of magmatism during the Mesozoic are responsible for the variable mineralisation in the Central Andes, including IOCG, magnetite and ‘manto-type’ deposits. The ore modelling for both the Middle-Late Jurassic and Early Cretaceous metallogenic epochs in the Central Andes are reconstructed.CITATION:Chen, H, 2015. The Mesozoic iron oxide-copper-gold (IOCG) mineralisation in the Central Andes – a refined IOCG ore-forming model in the Palaeozoic Continental Margin, in Proceedings PACRIM 2015 Congress, pp 251–254 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Ernest F. Burchard

A Reconnaissance of the manganese- and chrome-ore deposits of Cuba was made by the writer, as a representative of the U. S. Geological Survey, in company with Mr. Albert Burch of the Bureau of Mines, under instructions of the Secretary of the Interior, in the spring of 1918. The Cuban Government courteously detailed Sr. E. I. Montoulieu, a mining engineer connected with the Treasury Department, to act as escort and associate throughout the work on the island. The object of the study was to obtain authentic information for use of the United States Government as to the location, character, quantity, and availability of the manganese- and chrome-ore deposits in Cuba. Accordingly, the work comprised examination of such deposits as seemed to be of promise, without regard to stage of development, with a view to a determination of the quantity and quality of ore likely to become available for shipment during 1918 and 1919, and of the tonnage of ore in reserve. Wile it was possible to visit most of the deposits that seemed to be of promise, there was not sufficient time to visit all that were brought to our attention, some of which may have merit. Moreover, the necessity for paying particular attention to the ore deposits and the mines precluded the possibility of making more general studies of the geology of the region, and of making satisfactory collections of country rock and of fossils, and so for other details as to the geography and geology of Cuba the reader is referred to the report by Hayes, Vaughan, and Spencer.l Mr. Burch returned to the United States about 10 days in advance of the writer, who continued, in company with Sr. Montoulieu, investigations of reported deposits in Pinar del Rio, Matanzas, and Santa Clara Provinces. On his arrival in Washington, Mr. Burch submitted to the Director of the Bureau of Mines a summary of the results of the work to date. Later the writer published, as Press Bulietin 190. 380 of the U. S. Geological Survey, a statement concerning the chrome and man-

Jan 1, 1920

By James L. Eirls

Tracor MBA under a contract to U.S. DOI Bureau of Mines designed, developed, fabricated and demonstrated a conveyor belt service machine. It is self-contained, battery powered, rubber tired and capable of handling, storing and transporting conveyor belting, wire rope and associated structures for sectional conveyor belts. While moving the tail section to its next position the machine discharges the belting, wire rope and belt structures. The belting is elevated and separated to provide for the insertion of the structures with minimum expended effort. A hydraulic system provides the power for steering, braking, winding or unwinding under controlled tension the belting and wire rope, operating a load-bed slat conveyor, raising, lowering and locking connection hitches and powering external hydraulic tools. Also, a pneumatic system is available to operate air impact tools. The service machine, with its present components can function in coal seams as thin as 48 inches, double wind conveyor belting 42 inches wide, 400 feet long, load or unload 3/4" wire rope on two separate reels and is controlled by two operators. A complete belt move using this machine requires only four workers. Successful underground demonstrations were conducted in coal mines located in West Virginia and Kentucky.

Jan 1, 1983

By Shu Yan

The high resolution resistivity method (HRRM) is developed specifically for detecting underground cavities and tunnels. HRRM has a special feature in that it can recognize and cancel static shift, which makes it different &om the high density resistivity method (HDRM). In searching for various means for detecting underground cavities, we found that the detecting depth of the transient electromagnetic field method (EM) depends mainly on the measurement duration, not the loop area. In addition, TEM can also be used to locate the high-resistivity bodies. In order to use them for local working site conditions, we combine HRRM with TEM to become a combined electromagnetic method. Since the late 1980's this method has been used to locate abandoned mines and air passages and burning centers of mine fires with great success. This paper cites case studies for which this technique was successfully used.

Jan 1, 2005

By C A. Heinrich, J L. Walshe, V J. Wall

The Porgera Gold Mine, located in the highlands of Papua New Guinea, has produced over 5 million ounces of Au, since its opening in late 1990. The deposit is located within Upper Cretaceous Papuan Platform sediments approximately 25 km south of the Lagaip Fault, and is spatially and temporally associated with the 6 Ma alkaline Porgera Intrusive Complex.

Jan 1, 1995

By W. H. Liu

The stability of floors of large drydocks and wagon tipper sheds at coal terminals is an important matter but quite difficult to solve. Anchors can be used to join floors to foundations thus ensuring the stability of floors by the self-weight of floors and the pull of anchors. In this paper, the author describes the structures and types of the anchors used in the floors of the drydock in Beihai Shipyard and the wagon tipper shed at Shijiu Port, both in Shandong Province China, the determination of bearing capacity of anchors in rock bed of highly weathered granite, the comparison between prestressed anchors and non-prestressed anchors, the construction technology of anchors and the analysis of field experimental data.

Jan 1, 2010

By Javier Enrique Basurco Cayllahua

In this work, a gram-positive bacteria was used as biosorbent to elucidate the aluminum load capacity under different conditions related to metallurgical and chemical plants. The sorption data followed the Langmuir, Freundlich, Dubinin-Radushkevich isotherms. In order to determine the best isotherm fit, three error analysis methods were used to assess the data: correlation coefficient (R2), residual root mean square error (RMSE) and Chi-square test. The error analysis established that the Dubinin-Radushkevich model fits better the aluminum biosorption data. The maximum sorption capacity was found to be 41.59 mg.g-1. The maximum removal of aluminum was 95% at pH around 5. The experimental kinetics data was evaluated considering two models (pseudo-second order and pseudo-first order). This study indicated that the R. opacus is an environmental friendly biosorbent.

Jan 1, 2009

By Joseph L. Buckley

A total of 55 conveyor belt fire tests were conducted in the Bureau of Mines Fire Test Gallery, located at the Factory Mutual (FM) Fire Test Center West Glocester, R.I. The objectives of these tests were to: 1) determine the fire resistance and burning characteristics of various conveyor belt materials under simulated mine conditions; 2) provide essential data for designing a reliable bench-scale conveyor belt fire resistance test; and, 3) determine fire test conditions that will discriminate between low, moderate and high fire resistant materials. Belts, representative of those which mold he found in underground coal mines were examined under n umber of experimental conditions which included; ignition intensity; air flow rate; ratio of belt bright (h2) to overall gallery height (h1); exposure time; and, belt width. It was found that fire propagation could be achieved for some "fire resistant" belts (complying with the present Schedule 2G standard for approval) when exposed to an Ignition source of =6000 Btu/min for a 15-min period at a belt height ratio of 01.66. There appears to be a dependency of flame propagation on air flow rates and belt width, although the tests performed do not provide a quantitative trend. Recommendations are made for additional work to resolve some anomalous date and to fill voids in the rest program.

Jan 1, 1978

By James A. Pendleton

In response to Public Law 95-87 (SMCRA), Colorado promulgated regulations governing the mining of Coal. These regulations require the prediction, monitoring and mitigation of "material damage" caused by subsidence. All permitted underground coal mines within Colorado have approved subsidence programs. Preliminary monitoring results indicate the subsidence mechanical predictions have been sufficiently accurate to preclude material subsidence damage. The State of Colorado has developed a practical approach to regulating subsidence, which stresses monitoring verification of predicted subsidence phenomena. However, shortcomings exist in our ability to precisely predict the secondary consequences of subsidence, including effects to structures, the hydrologic balance and the environment. Lack of accuracy in predicting these secondary consequences results in uncertainty, necessitating conservatism in permitting. To avoid increasingly stringent permit restrictions, future research should emphasize the secondary consequences of subsidence.

Jan 1, 1986

By Brian W. Stump, David P. Anderson

Identification of seismic events detected under a Comprehensive Test Ban Treaty requires a clear physical understanding of the different types of seismic sources including mining explosions, rock bursts, mine collapse and small, shallow earthquakes. Constraint of the operative physical processes in the source region and linkage to the generation of seismic waveforms with particular emphasis on regional seismograms is needed. In order to properly address the multi-dimensional aspect of data sets designed to constrain these sources, we are investigating a number of modern visualization tools that have only recently become available with new, highspeed graphical computers that can utilize relatively large data sets. The results of this study will provide a basis for identifying important physical processes in the source region that contribute to regional seismograms.

Jan 1, 1995