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By Wawa Jaka Sungkawa, Slamet Rachman Jaka, Tom Dermody

Nowadays, with such a focus on environmental protection, surface mining activities have come under pressure to ensure their activities do not adversely affect the local surroundings. As part of the extractive process, blasting activities are an integral part of a mining company’s operational cycle. Consequently achieving beneficial blast results while complying with environmental requirements has become a key focus. This especially is the case when firing blasts within close proximity of residents where additional control measures need to be implemented to control vibration. One case where this occurs in Indonesia is in the Paringin Pit, one of the operational areas of the company's. The pit has complex geological conditions and is surrounded by several residential areas. Between 2014 to 2017 there were 12 cases of ground vibration exceedance due to blasting. As part of a continuous improvement project the company's targeted minimizing the vibration exceedance in this area. A project was undertaken to research and develop a method to confidently predict vibration. It was decided that the scaled distance formulas were not adequate to predict vibration when using non-electric detonators, as accurate wave propagation could not be achieved. The problem is how to manage of complex geology condition related with wave propagation in ground vibration control. Geological condition mapping with specific spatial range can and combine with Signature Hole Analysis be a solution to make wave propagation easier to accommodate in ground vibration control. With this new approach geological condition mapping with specific spatial range was produced that would minimize vibration while ensuring beneficial blast results. Introducing the new prediction produced nil cases of vibration exceedance in 2018 and beyond and proved that the Signature Hole Analysis in specific spatial range of geological condition is the preferred method to optimize blast result and maintain vibration control.

By S. J. Broderick

[Xuge d-mp heap co:lt:.ini9: tilcu?:na3s of tons of cad ~eP~se 2r3 a failiar sight in coal-mininc regior@:. T5ey reprecei~t considergole economic 1083, are very l.u.,si~hC,ly, ?:ld t?ke un m-lch vaL-x3le qace. Cor.sequentl;r thelr remcval i~ geatlyr dezir36, ax2 my ret-sn t?-at c,m be obtained would be er;pecic.llj .a~elconre&apos; t.7 the cod ir.S..r; kry. T?.e vaste rk.t~ri..tl conpl-ises large pieces of slr.t.e, hi~h-2s&apos;. bore c~al., luqs cf cle:., ,ad finer refuse conin,= fro3 the vrtskery, Tilt 1:zshcr:r refilsn contnins sone yood coal. Rig coal and the &apos;better p~lcs of bore ere the zat~rla2.s ~15:;~itiered in this in- vest ig:?.tion. 7% Il~avter frnctions of the w~~sherjr ref;lw aizd tts large 2ieces of slcte ?,".:I rgck contilin 1it:lei ccai-i-bcna.c~o~s caterial ad are vir- tu<dly worthiess nc, rz:. ::atcrin!. for .*=irin,= zct,iv?*teb cCvb~n. 13 the 3irniingh.m district, i13br.12, a-c.ju",P p?rcccn",f the c3sl r?.ir?ed is washed, ,md in tkis c?i.;trict nlz:~c rcfilce ecc;:?:lletcs ~t the r%tg of 1 to 2 million .! tons 2 yew.]

Jan 1, 1941

By A. D. S. Gillies

The use of refuge chambers for use in handling underground emergencies is an issue of topical relevance within the US mining industry. Chamber design is of importance to meet some new safety requirements of US federal and some state government mine regulations. A review has been undertaken of a steel mine refuge chamber design to predict what will be internal temperature within the chamber over an extended period with miners present? The design has been examined for the situation when the chamber is sited in still mine air. Spreadsheets have been developed to allow various design assumptions to be tested. The evaluation has been undertaken using thermodynamic heat transfer models with some assumptions specified to produce a model of appropriate simplicity but with adequate degree of accuracy. Under normal still air conditions it can be seen that internal chamber conditions rise quickly to often arduous conditions. There will always be quite a few assumptions necessary in complex heat transfer process evaluations. Some important refuge chamber design parameters are: ? External surface area of the chamber, its wall thickness and construction. ? Metabolic heat generated and number of persons making use of the chamber. ? The temperature of the external mine atmosphere to the chamber over the year and the influence of geothermal gradient on temperature at depth. ? The maximum internal chamber Apparent Temperature considered safe. ? The distance inside the underground mine and adjacent ventilation conditions.

Jan 1, 2012

By M. A. Reyes, L. Yan

Heat and humidity buildup withn refuge alternatives (RAs) may expose occupants to physiological hazards such as heat stress. The Mine Safety and Health Administration (MSHA) regulations require RAs in underground coal mines to provide a lifesustaining environment for miners trapped underground when escape is impossible. RAs are required to sustain life for 96 h while maintaining an apparent temperature (AT) below 95 °F (35 °C). The National Institute for Occupational Safety and Health (NIOSH) tested a 10-person tent-type RA, a 23-person tent-type RA, and a 6-person metal-type RA in its underground coal mine facilities to investigate the thermal environment over a 96-h period. The test results showed that mine air and mine strata temperatures surrounding an RA occupied by simulated miners (SMs) increased over the 96-h test period. The test results suggest that RA manufacturers should consider this increase in temperatures when calculating and evaluating RA components during surface and laboratory tests. The findings can equip stakeholders with additional considerations for calculating the interior heat and humidity temperature profiles for occupied RAs not tested in situ.

By M. Sagheer

An 8.5-km (5-mile) conveyor has gone into operation in western Turkey to eco¬nomically transport crushed lignite from the mine area to a power plant. This conveyor has replaced trucks as the principal mode of transporting the lignite. One principal element of Turkish govern¬ment policy is the country&apos;s commitment to increase electricity supplies for mining and other industries. Lignite is an important source of electric power supply in Turkey. Production was about 48 Mt (53 million st) in 1987, amounting to more than 20% of the total power supply in Turkey. In the western Anatolia supply network, it plays a major role for power generation. Deposits are located in the Soma region of western Turkey. The lignite is of low quality, deposits are scattered, and the terrain is dif¬ficult and hilly. These conditions demand an economical and technically feasible method of transporting the raw material from mining areas to the central thermal power plant. The Soma power plant is located about 120 km (75 miles) northeast of Izmir, near the coast of Aegean Sea. An overland conveyor of a unique design has gone into commercial operation at the Soma power plant facilities of the Turkish state electricity organization, Türkiye El¬ektrik Kurumu (TEK). The conveyor re¬places truck transport to ensure economical use of the lignite deposits. Computer-aided design (CAD) added more precision, qual¬ity, and flexibility of engineering in design activities. It also helped quick realization of the project that was executed in cooperation with the German company Krupp Industri¬etechnik and the Turkish firm Gama Endüstri AS. Unique features The conveyor includes several major features rarely combined in a single flight: Overland long distance conveyor. • Horizontal curves. -Steep vertical concave and convex curves to match the difficult terrain. Down-hill conveying. Frequency converter drives with vari¬ able belt speed. Generating operation mode to backfeed the energy to the network. Layout The 8.5 km (5 mile) long conveyor takes the -200 mm (-8 in.) lignite from the primary crushing plant located near the mine to the central, final crushing plant located in the stockyard area near the power station. The drive and belt tensioning assemblies are situated near the tail end of the flight. The high voltage switchgear is housed in a room in the primary crushing plant build¬ing upstream from the conveyor flight. The frequency converters are installed in the low voltage switchgear room located below the control room within the primary crushing plant building. Conveyor design The conveyor includes two 4 km (13,120 ft) radius horizontal curves, one left-hand and the other right-hand. The minimum radii

Jan 1, 1989

By C. Bachmann, M. J. Laurila, A. J. Widenman, A. Klein

Elemental analysis of slurry streams using X-ray fluorescence (XRF) has long been employed. However, detector technology has limited the application of XRF devices. Using detector technology employed on NASA&apos;s Mars Pathfinder to analyze soil samples, Process Control, Inc. has developed an on-line analyzer to mount on a sampling system. The prototype XRF elemental analyzer was installed at Detroit Edison&apos;s Monroe Power Plant in January, 1998 and has been employed to monitor feedstock quality. A slurry system has been developed for flotation control. This paper describes the testing of the analyzer using the new, draft ISO standard for evaluating the performance of online analyzers (ISO/DIS15239).

Jan 1, 1999

By Shirleny Fontes Santos

Muscovite mica crystals lower than 15 mm diameter are discarded as waste in the mining area of Borborema-Seridó (BRAZIL). The objective of this work was the ore dressing and purification of this waste to be used in the preparation of pearlescent pigment. Muscovite was dry ground using knife mills and an ultrasound treatment. It was possible to achieve 67% of mica with particle size lower than 100 µm. This product was used in the preparation of brilliant pigments based on muscovite flakes covered with rare earth oxides (CeO2, PrO2, Ce0,95Pr0,05O2). The pigments were characterized by X-ray diffraction, thermal analysis and scanning electronic microscopy. The color of the resulting pigments was analyzed using the CIELAB method and it showed the following colors: muscovite-CeO2 ? yellow, muscovite-PrO2? black and muscovite-Ce0,95Pr0,05O2 ? orange. Those results have shown that ?trash mica? is suitable for use in pigment preparation.

Jan 1, 2010

By G. M. Kintz, Charles B. Carpenter, G. W. Jones

"INTRODUCTION At 9:12 a. m. on April 16, 1947, the ammonium nitrate cargo in hold 4 of the S. S. Grandcamp, a 7,176 gross-ton Liberty ship owned by the French Government, detonated at pier 0 of the Texas City Terminal Railway Co., Texas City, Galveston County, Tex.This detonation was the first of a series of explosions and fires that took the lives of approximately 600 persons, injured 3,000 other persons, and caused a property damage and business loss that will exceed $58,800,000. It has been estimated that the life, accident, and workmen's compensation insurance loss will be $8,200,000.At 1:10 a. m. on April 17, 1947, the ammonium nitrate cargo in hold 5 of the S.S. High Flyer, a 6,214-gross-ton Liberty ship owned and operated by the Lykes Bros. Steamship Co., Inc., detonated at pier L. This explosion materially increased the property damage caused by the first explosion, in between 50 and 100 persons, and is believed to have taken the life of only one person.The exact number of casualties resulting from the Texas City disaster may never be known. On June 22, 1947, 65 days after the explosions, the red Cross and the Texas Department of Public safety repoted:,""Identified dead, 405; unidentified dead, 63; believed missing, 100; injured, 3,000; hospital¬ized, 600; still in hospitals, 37."""

Feb 1, 1948

By F. Russo-Bello

TauTona Mine (the renamed Western Deep Levels East) is using a longwall mining method with stability pillars to extract the Carbon Leader Reef at a depth ranging from 2097 metres to 3456 metres below surface. Seismic activity and the complexity and hazards associated with negotiating geological features at great depth pose the most severe hazard to deep level gold mining in South Africa. It impacts negatively on safety and the profitability of the mining. The critical success factors in longwalling at depth are: ?Sound mining strategies and face shape control ?Ensuring follow behind development infrastructure is kept up to date ?Support system design as a strategy to effectively limit the serious effects of damaging seismicity. This paper describes the following: ?Implementation of the required mining strategies ?The evolution of a new stope support system and problems associated with its development and implementation. How this support system was adapted for the successful negotiation of major geological features with known seismic potential and problems encountered ?Current initiatives to optimize follow behind development infrastructure ?Current initiatives in designing a new gully support system and problems experienced with its development and implementation. Finally, this paper will deal with the way forward, briefly covering areas like the above-mentioned gully support system, the proposed phased introduction of technology, and the use of alternative mining layouts.

Jan 1, 2000

By W. E. Stephens, A. J. Boyce, D. Lowry

Paper presented at Mineralisation in the Caledonides, the Mike Gallagher memorial meeting held in Edinburgh, 27-28 June 1996. An integration of S isotopic, fluid and mineralogical data for granitoid-related mineralisation showed that the porphyry systems had a predominantly subcrustal magma source, but the inner magma pulse of two-mica granite in the Fleet pluton was derived mainly from reduced sediments. The porphyry-style mineralisation formed from boiling fluids at high crustal levels, with a moderately saline fluid percolating down to the upper veins as they cooled but not penetrating the deeper Talnotry deposit. Veins in peripheral greywackes have a significant magmatic component but also incorporated CO2-rich components and metals released by dewatering of host sediments in response to granitoid intrusion. The low grade of regional metamorphism resulted in the significant fluid input from country rocks which led to the more exotic mineral compositions, especially where argillaceous sediments were involved

Jun 19, 1905

By Paulo Henrique da Silva Gomes

O tráfego rodoviário de cargas está em franco crescimento, se diversificando nas rodovias e também nos grandes centros urbanos. O uso de novos implementos (carretas maiores e com maior capacidade de carga) resulta no travamento das vias urbanas, causando grandes transtornos à população. Em muitas cidades, o tráfego exige um novo planejamento urbano e construção de vias alternativas. Em Volta Redonda, RJ, estão sendo desenvolvidos projetos com alternativas de fluxos rodoviários, que buscam soluções para o transporte coletivo, bem como, para fluxo de veículos pequenos, médios e de cargas da cidade. O fluxo de caminhões que abastecem e escoam os produtos da CSN - Usina Presidente Vargas, tendem a crescer com o aumento de produtividade da planta de Cimentos e startup da planta de Aços Longos, com início de suas operações em Janeiro/14. Alternativas como a intensificação do uso de ferrovia são foco do trabalho da área de logística da CSN, porém não eliminam o uso do modal rodoviário.

Jul 29, 2018

By Howard P. Hamlin

This Bureau of Mines report is concerned with the testing procedures for evaluating clays, shales, and slates for lightweight aggregates using the rotary-kiln method of production. To meet the increasing demand for light-weight concrete, rapid, accurate methods for appraising raw materials for light-weight aggregate are needed. Preliminary tests were made on samples of clay, shale, and slate, using laboratory equipment, and the data were used to establish operating conditions for pilot-plant-size rotary-kiln tests. Lightweight concrete was made from the processed aggregates and the properties determined. The results show that the laboratory data can be used to guide rotary-kiln testing, and, with the exception of sampling, a complete appraisal of a raw material for lightweight aggregate concrete can be made in 3 days by the methods described in this report.

Jan 1, 1962

By J. R. Nettle

The development of a process for upgrading offgrade titanium metal by electrorefining in molten salt led to an investigation of the electrotransfer characteristics of selected metals when alloyed with the titanium to be refined. Previous tests on seven binary titanium alloys showed that the degree of transfer of the alloying constituent depends on the constituent and on the operating procedurese.5 This report describes tests on electrorefining ternary mixtures of titanium with selected metallic elements. Ten alloys were prepared from high purity titanium and 2-1/2 percent of each of the metal pairs selected from the same elements used in the binary study; manganese, vanadium, chromium, zirconium, tin, molybdenum, aluminum. Operating variables were similar to those investigated in the binary alloy study that gave minimum alloy metal transfer. The data presented indicate the transfer characteristics of the various metals and combinations tested relative to each other.

Jan 1, 1962

By Jack J. Ayotte, Michael R. Nadon

"Today&apos;s demand for better and more efficient methods inspires new approaches to construction and mine development.A project at Asarco&apos;s Aquarius Mine provided a challenge that resulted in the adaptation of a civil construction technique to a mining application.This paper describes the construction of an escapeway shaft to surface from the mine&apos;s 150m level. The prime consideration was to provide the most cost-effective method of establishing a shaft collar in the 145 ft (44 m) of water-bearing overburden. This problem was resolved with the employment of the drilled in-caisson method.The remainder of the 500ft (152m) deep shaft was raise bored and portable hoisting equipment was used to install a permanentmanway and shaft liner.IntroductionHaving completed the first phase of exploration development in 1982, J.S. Redpath Limited was engaged to carry out an engineering and cost study to investigate the feasibility of re-opening Asarco&apos;s Aquarius Mine near Timmins, Ontario. The scheme was to develop the proven ore reserves and proceed with shrinkage stoping while carrying out further exploration development and diamond drilling.One significant and costly component of the project was the provision of an escapeway shaft to supply additional ventilation as well as a second means of egress from the mine. The major complication to this task was the presence of 145 ft (44 m) of water-bearing overburden at the site. The first and obvious approach was to use conventional ground-freezing methods as had been employed previously on .this property for the initial development shaft. This being the only ""sure"" method available at the time of the budget estimate, it was used as a basis for the study but its considerable projected cost and time demand inspired further investigation into other possible solutions.After considerable research and several brainstorming sessions, a Redpath team came up with an approach whose basic procedures had been used extensively in the civil construction field, although they were novel to the mining industry."

Jan 1, 1987

By J. Chlopas, D. J. Barratt, M. V. Sharp

"This paper describes the modifications made to the Fox Mine copper concentrate bin in order to obtain a continuous flow condition. The design of these modifications is based on test results obtained on Fox Mine concentrate using the flow factor testing machine in the research facilities of Cominco at Trail, B.C.The original design consisted of a cylindrical steel bin on a concrete slab with two slot-discharge openings. Based on predictions of the maximum mass flow hopper angle for conical and wedge shaped hoppers for the concentrate on various potential bin lining materials, Ultra-High Molecular Weight (UHMW) Polymer was selected as a liner.Using the recommended angles for conical and wedge shaped hoppers, the profile of the bin base was changed to suit the existing slot openings.The initial method of fastening the liner resulted in failure of the connections. Subsequent modification to the zinc concentrate bin fastener system proved satisfactory and it has now been in operation for over one year without any separation of the lining material.Utilization of flow testing procedures on concentrate samples has demonstrated that proper design of storage bins or hoppers to achieve continuous flow can be incorporated into the design of new plants."

Jan 1, 1978

By WU Jian-hui

Keywords: metallic material, precursor synthesis, precipitation, nickel, fibrillar powder The composition and morphology of the precursor of fibrillar nanocrystalline nickel powder prepared by oxalate precipitation are characterized by XRD,IR and SEM analysis, and the effects of temperature, nickel concentration, pH, surfactant and drying process on the morphology and the dispersion of the precursor are investigated. By the experiment results, the fibrillar precursor is a complicated nickel salt. The precursor prepared in the of 60~70°C,0.6~0.8 mol/L nickel ion, pH=8.4~8.6 and with addition of PVP surfactant is well dispersive and in fiber form. The powder dried by azeotropic distillation is dispersive.

Jan 1, 2005

By Wilbur I. Duvall

In a review of so 40 papers on damage to residential structures resulting from blasting, only 3 were found that present data on the observed amplitude and frequency of the vibration levels produced by blasting together with an observed degree of damage to a residential structure. The data from these three reports have been analyzed statistically to determine if one of the quantities, displacement, velocity, or acceleration, is more reliable than the others for estimating the degree of damage to a residential structure. From this analysis the conclusion is drawn that a given degree of damage to a structure is most closely related to the magnitude of the particle velocity of the wave motion passing thru the earth at the structure location. On the average, only minor damage it observed for peak particle velocities of 5.4 inches per second, and major damage is observed for peak particle velocities of 7.6 inches per second. When the spread of the data is taken into consideration, the following statement can be made: Wave motions that have a peak particle velocity in excess of 2 inches per second have a fair probability of producing some damage to structures, whereas wave motions that have a peak velocity less than 2 inches per second have a very low probability of causing any damage. Therefore, the recommendation is made that vibration levels in the vicinity of residential structures should be maintained below a peat particle velocity of 2 inches per second. The above criterion for safe blasting is considered to hold over a wide variety of soil and rock conditions because the original data were obtained for a wide range of soil and rock conditions and on various types of residential structures. INTRODUCTION Ever since explosives were discovered and developed for mining purposes, there has existed the problem of what effects the air and ground vibrations resulting from blasting have on structures of various types. This problem is

Jan 1, 1962

By W. A. Wilkinson

In creating a surface mine design, a complicated series of events may be required to meet both mining and environmental objectives. Envisioning the mine at every step of the operation can greatly assist the engineer to identify design and operational problems that might otherwise go undetected until the field operations reach the problem. Providing operations a visual progression of the mine ensures that critical designs generated by the engineer are understood and effectively communicated to operations. Providing the plan as electronic data to the surveyors and/or on-board GPS systems can ensure successful implementation of the design. This paper discusses using computer technology to generate a virtual mine plan and strategies to consider when communicating a virtual mine plan through electronic and paper formats.

Jan 1, 2002

By Niels Krebs Ovesen

Close economic cooperation was established among the countries in western Europe during the seventies. As a consequence, among others, a need for harmonized technical specifications for civil engineering works arose. Technical specifications for design and execution of building and civil engineering structures exist in most of the European countries. In some countries such technical specifications are part of the building regulations and in other they are independent codes of practice and standards. The works on the Eurocodes was initiated by the Commission of the European Communities about 1976. The Eurocodes are intended as common unified design codes for different load bearing structures constructed from different materials. They are also intended to cover design of geotechnical structures. They are established with a view to promote the free movement of goods and services within the member states of the European Community - the so called Internal Market - and within the member countries of the European Free Trade Association, EFTA by removing obstacles arising from different rules for calculation and design.

Jan 1, 1994

By Wilbert J. Huff

This is the sixth of a series of annual reports describing the work of the Explosives Division, Bureau of Mines, United States Department of the Interior.3/ It deals particularly with the activities of the division from July 1, 1940 to June 30, 1941. The studies outlined in this and preceding reports of the series have been conducted under the direction of the author and the respective unit leaders, to whom specific credit is given.

Jan 1, 1942