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By D. C. Fuller

"CoaLiquid, Inc. (CLI) has been in the coal-oil-mixture (COM) business for over five years. The initial pilot processing facility was replaced by a 2000 barrel per day commercial production facility in August 1979. For over two years CLI has been expanding its efforts and conducting large-scale production and combustion demonstrations successfully in many locations across the United States. To facilitate the marketing effort, CLI has recently constructed a special trailer containing all equipment needed for a temporary COM retrofit.CoaLiquid has conducted commercial-scale combustion demonstrations in the following types of combustion units: kilns, calciners, industrial boilers, blast furnaces and driers.IntroductionCoaLiquid, Inc. officially dedicated its plant on August 31, 1979, at a ceremony presided over by the then Governor of Kentucky, The Honorable Julian Carroll. The dedication marked the culmination of over three years of research and development work and marked the beginning of a new era of coal-oil-mixtures as a commercial commodity in the marketplace. As the first such plant in the United States, it set the tone for construction to follow.CLI was originally owned and managed by a group of entrepreneurs from Kentucky who had developed the process and constructed the plant on purely private investment and conventional financing. Beginning in late 1976, with a pilot-scale operation, also located in Shelbyville, Kentucky (near Louisville), CLI began producing a stable mixture of 50070 coal, 30% to 40% oil and 10% to 20% water by weight. The technology employed was developed by Eric C. Cottell of Long Island, New York and is covered by U.S. Letters Patent No. 3,941,552. Since the pilot plant operation, CoaLiquid has made many refinements to its process and in fact has added new technology to its portfolio of patents and patents pending. Further refinements to the product now produce a stable mixture of 50% coal, 40% No.6 fuel oil and 10% water by weight."

Jan 1, 1985

By T. L. Joseph

The Bureau of Mines gas been studying the blast furnace for a number of years and has published detailed reports on various phases of its investigations. Inquiries frequently received for information of a more general character than that given in the detailed reports have promoted the preparation of an information circular to cover in a general way the important features of the Bureau of Mines blast-furnace investigations. SHAPE AND DIMENSIONS OF FURNACE The modern blast furnace approximate a refractory-lined steel cylinder about 90 feet in height and 25 feet in diameter. It actually consists of a number of cylinders and truncated cones superimposed upon each other. The shape and dimensions of a modern furnace are shown in figure 1. The bottom section, commonly referred to as the hearth or crucible, is a cylindrical section about 12 feet high. Liquid metal and slag collect in this part of the furnace and are withdrawn at regular intervals; iron is removed at a level about 2 feet above the bottom of the furnace and slag at a level about 5 feet higher. Depending upon on the size of tie furnace, 40,000 to 75,000 cubic feet of preheated air per minute is introduced through from 10 to 16 tuyeres equally spaced around the periphery of the hearth.

Jan 1, 1934

By S. Stebbins

In 1994 Western Mine Engineering, Inc., (WME), which is now InfoMine USA, Inc., set out to build a suite of stand-alone software programs that would provide their clients the means to estimate the costs of developing and operating mineral exploitation projects. After the first program (Sherpa for Surface Mines) was completed and launched, the developer (me) left WME to form Aventurine Engineering, Inc., in order to complete the series of applications. In the years since, four programs have either been developed or upgraded and enhanced. Applications were produced that estimate the costs of underground mining, placer mining, and project site reclamation. In addition, an application specifically designed to evaluate the economics of these projects, which was based upon a program previously developed for WME by Bill Willoughby of Willoughby & Associates, was redesigned and the code updated to a MicroSoft compatible platform. All these programs follow an engineering-based approach to cost estimating. Instead of relying on rules-of-thumb and statistical averages, they calculate all of the engineering and operational parameters needed to estimate costs. The premise is that the uncertainty associated with cost estimates should lie with the data available for the resource, not the approaches used to design and estimate the associated design parameters. In other words, it is acceptable that items such as the resource grades, deposit dimensions, ore and wall rock characteristics, and mill recovery rates carry with them some uncertainty, but parameters such as loader bucket capacities, truck speeds, pump horsepowers, hoist velocities, and grinding mill diameters can be calculated (although uncertain data might be used in those calculations). No additional uncertainties should be introduced because the cost-estimating procedure relied upon statistical manipulation or anecdotal inaccuracies. To that end, the programs rely upon calculation-based approaches to selecting and sizing machinery, assigning the required workforce, and determining the extent of the consumables needed to recover mineralized material at a rate defined by the client. And while calculation-based software is not unusual, more modern approaches work toward the development, accumulation, and manipulation of data. INITIAL CONDITIONS AND PROJECT GOALS In 2016 we had five separate programs completely disconnected from one another. Each was written in VisualBasic, a language that was falling from favor. In essence, the status in 2016 was a series of stand-alone programs (Figure 1) in which results from one needed to be manually entered as input into another.

Jan 1, 2019

By J. B. Lizak

This paper is not available for inclusion in the Proceedings at the time of printing, but it will be included as an insert.

Jan 1, 1984

By A. M. Dale, J. Standeven, B. Evanoff

We encountered several areas of methodologic uncertainty during development of a data collection method for use with vibrating hand tools in metal assembly. A local manufacturer sought our assistance designing a data collection method for evaluating and predicting risks of upper extremity disorders associated with use of vibrating hand tools. Current methods of vibration measurement are described in ISO 5349 [2]. However, the complexity of measuring vibration along with other exposures such as force and posture has limited the number of workplace-based studies of upper extremity disorders that have included direct measurements of vibration. Data from this preliminary study was used to look at two issues: a comparison of vibration values between production and non-production workers when performing the same task, and a comparison of worker ratings of vibration comfort to direct measurement of tool vibration. Methods Eight experienced production workers used each of six metal fastening tools to install fasteners. Vibration was collected by 3 tri-axial accelerometers, one attached to the tool handle following ISO 5349 recommended locations, one attached to the hand dorsum on the 3rd knuckle and one to the thumb side of the wrist. Data sampling rate was 10,000 samples/second. Hand grip and feed forces were obtained using a Novel pressure sensing mat on the palm. Each trial consisted of installing 10 fasteners per tool for each of the 6 tools. The test set-up placed the wrist in the position typically used by the operator during production. Each worker documented subjective comfort and effort ratings on a seven point scale following each series of fastener installations. One series of testing was completed by three non-production workers inexperienced in fastener installation to simulate use of alternative employees for data gathering. Vibration data for each trial were acquired, digitized, and stored using Lab View. The X, Y, & Z axes were used to calculate the vector sum response for each tri-axial accelerometer. The tool data were digitally filtered following ISO recommendations. Calculated data consisted of the mean RMS over the tool’s on- time, the starting and breaking peak impulses, and the peak of the frequency response. Results Production workers (n=8) were right hand dominant males with a mean age of 55 years and normal hand strength (mean right grip = 106 lbs). Non-production workers (n=3) had similar characteristics. We found large and statistically meaningful differences in hand force during tool use between production and non-production workers (mean production workers = 9.77 lbs, mean non-production workers = 43.30 lbs, p = 0.0001). Vibration values obtained from the hand also showed a statistically meaningful difference (mean in production workers = 0.67 Gs, mean in non-production workers = 1.48Gs, p = 0.0014, figure 1). Experienced worker ratings of comfort during tool use demonstrated a moderate correlation with measured vibration (r=0.63). Worker ratings trended with direct recordings from the tool handle as shown in figure 2.

Jan 6, 2006

By Edwin B. Cook

Studies of flame and combustion phenomena at the Bureau of Mines have been facilitated by computer evaluation of the thermodynamic properties of gases formed by constant-pressure burning.4 5 This report is the sixth of a series6-10 presenting results of such calculations; it deals also with constant-volume deuterium-air flames.

Jan 1, 1961

By Wolfgang Van Hooff

Encouraged by a strongly growing and evolving market for granulated products, Paul Wurth continuously improves its granulation and dewatering technologies to provide customers with state of the art installations. Continuously developed know-how about the granulation process of iron blast furnace slag enabled application to non-ferrous materials such as Ni-Slag, Pb-Slag, Blister Copper, Cu-Matte and even TiO2-Slag, which rank among the most difficult materials to granulate. This paper identifies how critical objectives in granulation and dewatering technologies applied to different molten materials with respect to various product quality objectives can be addressed. The differences between hot and cold water granulation systems are explained, including the step from cold runner to granulation water tank. Development of a flow and pressure controlled blowing box is the latest step to optimize the granulation process in order to meet the latest standards in terms of quality, power consumption and environmental protection.

Jan 1, 2006

By John Yenter

"Unique blasting problems during reconstruction and expansion of 100 year old buildings toaccommodate gambling. Located on steep mountainous terrain and linked by narrowroadways, the towns of Central City and Black Hawk challenged blasters to exceptionalmeasures in order to control over_break, vibration, public exposure and damage to thecharacter of these historic mining towns. Utilities were also upgraded to fit demands of asmuch as 800% volume change in one year."

Jan 1, 1993

By Kent C. Werle

This brief discusses the installation and application of sleeved piles of two different types for two different projects, the W, Seattle to Harbor Island Swing Bridge Project and the Seattle Access Project. A description of these relatively novel piling systems is given, as well as some notes on their installation and application. As implied by the term "sleeved" these are piles which consist of two piles, an inner pile combined with an outer concentric sleeve pile. Background, Swing Bridge The Swing Bridge project is virtually unique in the world in that it is a "lift and turn" swing bridge. It is also a concrete, cast -in-place segmental bridge which is designed to be moveable.

Jan 1, 1990

By A. P. Bois, K. Saleh, A. Ghorbal, V. Hajiabdolmajid, G. Ballivy

"The knowledge of the initial stress field is not always sufficient to ensure the stability of mining stopes due to the high-stress variations generated by mining. Monitoring of these openings is then necessary and can provide quantitative information (deformations and stress variations) as well as qualitative information (state of stability).An applied technique for following the variations of stress and deformation in static and dynamic conditions, in relation to the evaluation of the stability of underground openings known as “Cylindre Instrumenté de l’Université de Sherbrooke” (CIUS) is discussed in this paper. In addition, a data acquisition system combined with a rock failure warning system has been developed to be connected to the CIUS for detecting the instabilities, which can endanger the stability of underground openings. Also, the installation of six CIUS and a data acquisition system as well as the selected procedure of programming in a warning system are briefly described."

Jan 1, 2003

By Edgar J. Briceño

El presente texto señala el resultado de algunas pruebas realizadas en el período de 1974 y 1979 en la concentradora de Toquepala, a fin de mejorar el proceso de producción en la industria minera. Para ello, se ejecutaron 14 pruebas a nivel de planta, de donde se seleccionaron seis, las cuales se ejecutaron también a nivel de laboratorio para así compararlas con lo standard. Las seis pruebas referidas son: Evaluación de forros de jebe en molienda, evaluación de diferentes tamaños de bolas, evaluación del espumante Celaproht-16, efectos de Asmol Polhalla m- 59 en sedimentación y filtrado de las colas de planta de Molibdenita, evaluación del espumante Ucon R-23 y lonas tampereen en el filtrado,

Oct 14, 1980

By Lance McAnuff

The year 2001 coincided with the forty-fifth year of blasting-control specialization by the author. Commencing with the construction of the Saint Lawrence Seaway System in 1956 and continuing until the present time this career has spanned one of the most progressive and exciting periods in the still relatively short history of commercial blasting. The paper touches upon a number of the more interesting projects with which the writer was involved during those early days, including the removal by explosives of “Ripple Rock” the infamous underwater hazard to shipping which at one time inhibited ocean traffic along the Inside Passage between Vancouver Island and the mainland of British Columbia, Canada’s most westerly province. Various assignments involving incidents from devastatingly ,tragic to comically absurd are described, along with personalities encountered along the away, most of them readily recognizable as giants in the field of explosives engineering. Various stages in the evolution of state-of-the-art explosive products, initiation systems vibration monitoring equipment and limiting criteria are compared and some of the effects these have had on safety and productivity during the last forty-five years are analyzed.

Jan 1, 2002

By D. R. Hack

Increased consumption of concrete in the Pacific Northwest has pushed aggregate resource development pressure from urban areas west of the Cascade Range to rural areas east of the Cascades. Some recent development has focused on barge and rail accessible off-reservation Indian allotments that are exempt from state and county regulations. These lands have their own unique set of challenges, especially when Federal and Tribal governments have conflicting goals and attitudes pertaining to resource development. This paper discusses issues of leasing, reclamation, Federal vs. Tribal authority, cultural resources, and the history of allotment.

Jan 1, 2002

By G. J. Knighton

Introduction The Sullivan concentrator treats the complex lead-zinc-iron ore from the Sullivan mine of the Consolidated Mining and Smelting Company of Canada, Limited, to make a lead and a zinc concentrate for its metallurgical plants at Trail. Three miles separate the mine and mill, which are situated near the town of Kimberley, in the East Kootenay district of British Columbia. The orebody consists typically of banded sulphides, mainly galena, sphalerite, pyrrhotite, and pyrite. Important factors in the concentration of the ore are its exceedingly complex and its high specific gravity. It should be remembered throughout the paper that results and figures are based on Consolidated's experience with the Sullivan ore. The present mill feed rate is 8,500 dry tons of ore per 24 hours, for an operating week of five and a half days. Grinding and classification of the ore are carried out in three stages and, in addition, there is a re-grind section which re-treats the zinc middling. It is the purpose of this paper to discuss the classification in the various stages and to give the results o comparative tests which have been carried out for the purpose of improving operations in the mill. The Primary stage consists of six units, each made up of a ball-mill and classifier (see accompanying flow-sheet). Four units operate in open circuit and two in closed circuit. The secondary stage consists of eight ball-mills operating in closed circuit with twenty-one classifiers. In the Tertiary stage are two ball-mills in closed circuit with eight classifiers. The re-treatment section for re-grinding the zinc middling comprises one ball-mill in closed circuit with two classifiers.

Jan 1, 1947

By P. -É. Boileau, S. Mandapuram, Shiping Ma, S. Rakheja

The absorbed power (PAbs) has been suggested as a better measure of human responses to whole-body vibration, since it relates to the cumulative energy dissipated by the body exposed over a given duration. Moreover, unlike the other measures, the PAbs can adequately account for the intensity of exposure. Although, the vast majority of off-road vehicles impose considerably severe vibration along the horizontal axes, the vast majority of studies on biodynamic response characterization consider only vertical vibration. Only a few studies have reported PAbs responses of the seated human body exposed to horizontal vibration and the major contributing factors [1]. This study aims to characterize the PAbs responses of seated human subjects to horizontal (uncoupled x- and y-axis) vibration as functions of the vibration intensity, subject mass, seat height and the, type of back support. Methods Experiments were conducted using a rigid seat with an adjustable backrest inclination and seat height. The seat was installed on a horizontal vibration simulator and the forces at the seat base and the backrest were measured by three-axis force plates. Two single-axis accelerometers were installed on the seat back and the platform, oriented along the axis of motion. The experiments were performed using three different seat heights (350, 390 and 410 mm), back support conditions (NB- no back support and sitting erect; Wb0- Upper body supported against a vertical back support; and WbA- back supported against an inclined backrest, while sitting relaxed) and three different magnitudes of broad band excitations in the 0.5-10 Hz frequency range (0.25, 0.5 and 1 m/s2 rms acceleration under x-axis and y-axis, applied independently). A total of 8 healthy adult male volunteers with total body mass ranging from 59.4 kg to 92 kg and aged between 21-51 years took part in the experiments. The subjects were seated with their hands in lap, and feet supported on the moving platform for each posture. Each measurement was repeated 2 times, while the data were analysed using a bandwidth of 50 Hz and frequency resolution of 0.0625 Hz. [ ] The data were analyzed to derive the absorbed power characteristics of the body at both seat pan and backrest interfaces, while the coherence among the measured forces and accelerations wer

Jan 6, 2006

By N. Grosland, G. Kopp, T. Hunstad, D. Wilder, M. Contratto, S. Rahmatalla, T. Xia

Chronic whole-body vibration exposure, as expected in large construction and mining vehicles, has been associated with neck and back pain and injury.1 While work has been done towards gaining a better understanding of the relationship between vibration and shock and muscle activity of the back musculature2, relatively little information regarding the activity of neck, shoulder and upper arm muscles is known. Today’s equipment designs must conform to domestic and international standards, however these standards do not specifically address the vibration exposure in the head and upper quarter. Further it is not well known how the control configuration within a vehicle (e.g. steering wheel versus arm controls) influences muscle voluntary and reflex activity levels. Greater muscle activity may lead to greater muscle fatigue – which in turn may be associated with greater risk of injury.2 Thus, muscle contractions needed to maintain static postures as well as those resulting reflexively should be considered during an analysis of seating position. Unfortunately, little is known regarding the influence of arm position on head and neck muscle function. The purpose of this study was to investigate the relative muscle activities of 5 neck, shoulder, and upper arm muscles during riding simulations of large construction equipment, using three different arm control options. Methods Five typical heavy equipment ride files were “played back” through a man-rated Servo Test 6-degree of freedom (dof) vibration system. Each ride was repeated using 3 seat and control configurations (steering wheel (SW), floor mounted arm-rest controls (FM), seat mounted arm-rest controls (SM)). Two trials were performed for each ride and seat control combination (each trial: 60 sec of 6-dof and 60 sec of vertical vibration). Five channels of surface electromyography (EMG) of the right-side cervical erector spinae muscles (neck extensors), sternocleidomastoid (neck flexor), upper trapezius (shoulder elevator), biceps brachii (elbow flexor) and triceps brachii (elbow extensor) muscles were collected throughout each ride (~ 2min) using pre-amplified (10x), 1 cm silver bar electrodes, with 1 cm fixed inter-electrode distances (Delsys, Inc). Further analog amplification was set at 10k (1k for one subject), and sampled at 1000Hz using a 12-bit DAQ card and Labview 7.1 software (National Instruments). A total of 7 right-handed male subjects were tested, but only 5 had complete EMG data sets to analyze for this sub-study. EMG was analyzed using root mean square (RMS, in mV) of 20 ms moving windows, and then averaged across the entire trial for a measure of mean total muscle activity (voluntary and reflexive). The muscle activity to maintain the static posture was estimated as the mean RMS EMG over a 1 sec interval just prior to and/or after completion of the ride. Repeated Measures ANOVAs were used to test for with-in subject differences using a = 0.05.

Jan 6, 2006

By H. B. Brunot, L. C. IlsLey, E. J. Gleim

"INTRODUCTION To supply inspectors, safety engineers, and others with detailed information as to the safety features of the various electrically operated machines that have been approved as permissible by the Bureau of Mines, three bulletins and five reports of investigations have been published dealing with the various classes of approved machines:Bull. 313, Permissible Storage-Battery Locomotives and Power Trucks.Bull, 343, Permissible Coal-Handling Equipment Approved from January 1926 to December 1930, inclusive.Bull. 382, Permissible Coal-Cutting Equipment Approved Prior to July 1, 1932.Rep. of Investigations 3309, Permissible Electrically Operated. Air Compressors.Rep. of Investigations 3326, Permissible Electrically Operated Room Hoists.Rep. of Investigations 3345, Permissible Electrically Operated Rock-Dust Distributors.Rep. of Investigations 3363, Permissible Electrically Operated Hand-Held Coal Drills.Rep. of Investigations 3391, Permissible Electrically Operated Post Drills and Drilling Machines.The present paper gives similar information relative to the mine pumps approved before October 1, 1939."

Mar 1, 1940

By Rob Farnfield, Yuill Gavin

The rock blasting industry continues to be under pressure to reduce the level of vibration induced by the use of explosives. In recent years much research and development has been directed to minimizing vibration levels by controlling the delay period between blast holes. The most commonly applied technique is known as Linear Superposition. This technique takes the vibration produced from a single-hole test shot and simulates the vibration that would be produced from a full-scale production blast. The simulation can be run with various delay periods and the optimum delay chosen. The success of the Linear Superposition technique depends to a great extent on having accurate delay detonators and on the single-hole test shot reliably indicating the vibration signal produced from each hole in a production blast. A quarry-based case study is given illustrating how these assumptions are not always valid. In this case the use of electronic detonators has controlled frequency but not vibration level. The paper goes on to describe a series of single-hole test shots in an U.K. limestone quarry. The vibration 2 signals recorded are examined in terms of variations in free-face provision, blast geometry, explosive properties, etc.

Jan 1, 2001