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By Francois Reizine

Infrared sensors will include scanning detectors and positioning sensors. The focus will be on 1, 2, and 4-color wavelength pyrometer systems which allow the accurate measurement of emissivity and, consequently, of the true temperature even in the presence of scale, slag, and fumes. Such sensors are being used in blast furnaces, BOF's, and galvanizing lines. Laser sensors will be presented using different principles of physics, mainly time-of-flight, pulsed infrared lasers for level measurement and dimensional measurement; triangulation lasers for width and thickness measurements; and laser Doppler velocimeters for velocity and length measurements, including mass flow, elongation, and tension control, cut-to-length applications. These sensors and systems are based on state-of-the-art technical developments to improve productivity and quality and reduce maintenance and downtime.

Jan 1, 2001

By David R. Delling

Introduction In 1967, Tenneco acquired Kern County Land Co. The primary reason for the acquisition was to obtain Kern's agricultural, manufacturing, and oil interests. Included in the Kern portfolio were the core of Tenneco's present sodium leases in Sweetwater County, WY. This lease base has been ex¬panded and now consists of 62 km2 (24 sq miles). Beneath this property lies more than 500 Mt (550 million st) of economic trona ore. Following the Kern acquisition, Tenneco continued exploration and feasibility studies concerning the trona leases. The effort was accelerated in 1976. Tenneco was attracted to trona because of the favorable lease position it held, the growth rate of the Wyoming industry during the 1960s and 1970s, and the prospects for a long-term, stable business enterprise. The reserve picture was certainly attractive to a company long accustomed to the never-ending struggle to replace oil and gas reserves. In 1978, Wyoming was a boom area that had experienced rapid growth for a number of years. Unemployment was very low and vacant housing nonexistent. The prospects for soda ash were somewhat different in the 1970s than now. But it was recognized even then that a new producer would have a challenging task to compete in this business. Tenneco knew the capital burden required to build a grassroots facility during inflationary time, would have to be offset elsewhere Since labor and energy are the dominant direct costs in mining trona and producing soda ash these factors have always received a great deal of attention. Contracting and permits Environmental monitoring on the site began in late 1977. With the already mentioned considerations in mind, engineering began by mid-1978. Brown & Root Inc. was selected as the general contractor for the project. S. A. Scott & Co. was the engineering subcontractor for the mine shafts, hoists, ventilation system, and miscellaneous mine facilities. Frontier-Kemper was awarded the contract for sinking the two mine shafts. Acquisition of numerous federal, state, and local permits occupied all of 1978 and 1979. The Wyoming Industrial Siting Permit, which addresses socioeconomic issues, drew the most public interest. Siting issues were all satisfactorily resolved by negotiating reasonable stipulations with various local governmental units, school districts, and the like. Site location The Green River project location is not truly remote. It is located within 5 km (3 miles) of Interstate 80 and only about 32 km (20 miles) west of the city of Green River. Nevertheless, a substantial investment had to be made in communication and utility links to the site. These included: • A 14-km (8.5-mile) rail spur connecting with the Union Pacific Railroad at Bryan, WY. This spur has four bridge structures including one crossing Interstate 80. Most soda ash is shipped by rail, and coal is received over this line as well. • A paved 5-km (3-mile) roadway connecting to Interstate 80. • A powerline extension of about 27 km (16.5 miles), along with two new substations. • A 24-km (15-mile) waterline connecting the plant to a pump station on the Green River. The site is located on gently sloping terrain at an elevation of about 2.1 km (6800 ft). Ground conditions are good for construction. Weathered bedrock lies near the surface in most places. Geology The general geology of the Green River Basin has been well described previously. Tenneco's ore is in several superimposed evaporate beds. But the bulk of it is present in Bed 17, located about 457 m

Jan 10, 1985

The mineral Industry, following the economy as a whole, experienced little growth in 1992. However, with modernized plants, efficient workforces, and lower operating costs, the industry is well positioned to take advantage of possible improvement in the national economy during 1993. In addition to the significant 1992 events highlighted below, important events, trends, and issues within individual mineral industries are addressed in the commodity sections that follow. The value of processed materials of mineral origin is estimated to have been about $310 billion in 1992. The value of U.S. raw nonfuel minerals production in 1992 is estimated at approximately $32 billion, a 3% increase over 1991. The value of domestic minerals production has increased in all but 4 of the last 32 years.

Jan 1, 1993

By W. H. Strickland

Ultrasonic ranging sensors are inexpensive, have no moving parts, have no lenses to clean, are normally small and unobtrusive, and can measure distances through moderate amounts of dust, smoke, and humidity, so they are well suited to underground mines. In the work reported here, conducted by the U.S. Bureau of Mines, researchers tested ultrasonic ranging sensors for their ability to define rib line features for computer-aided navigation of underground mine mobile equipment. The investigation began with laboratory tests of field of view, angle of incidence, intersensor variation, and ranging accuracy of the individual rangers in a ring array produced by Denning Robotics of Wilmington, MA, The results showed that the sensors have good accuracy and low variability. Additional experiments at AMAX'S Henderson Mine showed the sensors could accurately and reliably measure the distance to mine features, including convex and concave corners and rib intersections. The results showed that when used properly, the ranger data are accurate enough for reliable mine vehicle navigation. When used incorrectly, ultrasonic rangers do not provide the anticipated data. Therefore, this report explains the principles of ultrasonic range measurement, describes the ranger's strengths and weaknesses, and explains proper ranger use and data analysis.

Jan 1, 2010

By L. G. Marshall

This report presents a cross section of the sand and gravel operations in the Minneapolis-St. Paul area. The study covers individual operations, economic problems peculiar to the industry, glacial geology of the area and its effect upon the grades and types of products, and past, present, and future trends of the expanding population and its effect upon the industry.

Jan 1, 1963

By L. G. Marshall

This report presents a cross section of the sand and gravel operations in the Minneapolis-St. Paul area. The study covers individual operations, economic problems peculiar to the industry, glacial geology of the area and its effect upon the grades and types of products, and past, present, and future trends of the expanding population and its effect upon the industry.

Jan 1, 1963

By S. H. Ash

THE MAGNITUDE of the anthracite industry's drainage problem in the Northern field of Pennsylvania is realized when it is known that, for the 8-year period 1944-51, all pumping plants in this region pumped an average volume of 112.5 billion gallons of water from the mines to the surface each year. This is over 214,000 gallons per minute pumped against an average hydrostatic head of 400 feet each year for that period (12).4 By comparison, Lake Wallenpaupack, the largest artificial body of water lying wholly in Pennsylvania, contains 71 billion gallons of water in its 24-square-mile area; the average volume of water pumped from the mines in the Northern field each year during the 8-year period was 58 percent more than the volume impounded in Lake Wallenpaupack. The natural configuration of the drainage area overlying the Northern field subdivides the total area into two major drainage areas-the Lackawanna River drainage area and the Susquehanna River drainage area overlying the Wyoming Basin. Although the 169-square-mile drainage area overlying the Wyoming Basin is slightly less than half that of the Lackawanna River drainage area (10), the total volume of water pumped to the surface from mines in the Wyoming Basin is 21 percent more than the total volume pumped to the surface from mines in the Lackawanna Basin. From this, it is apparent that the Susquehanna River and the pervious deposits in the buried valley over which it flows in its course across the coal measures of Wyoming Valley is the greatest single source of mine water affecting mines in this area. Because of its relatively flat terrain, the wide flood plain of Wyoming Valley does not facilitate rapid runoff; consequently, much of the surface water seeps directly into the buried-valley deposits and eventually into the mine workings.

Jan 1, 1953

By H. H. Schrenk, Carlton E. Brown

"The purpose of this paper are (1) to present a broad picture of the recognized methods of measuring the various forms of atmospheric pollution; (2) to evaluate the significance of such measurements; and (3) to suggest suitable methods for obtaining comparative information on the concentration of contaminants in city air.The atmosphere (the gaseous envelope surrounding the earth) consists of a mixture of gases. These gases and their usual proportions are:4/The volume of water vapor in the atmosphere ranges from almost zero (in very cold weather) to about 5 percent arid averages about 1.2 percent.Strictly speaking, any other substance in the atmosphere or an excess of any of the substances mentioned (with the possible exception of water) is a contaminant. Needless to say, there are many contaminants in the atmosphere.In accordance with their physical state, contaminants may be classified as gaseous or particulate, and the latter may be classified as solid or liquid matter. Particulate matter, especially when dispersed in some medium such as air or some other gas, sometimes is referred to as dispersoid, and the complete system of gas and dispersoid is referred to as aerosol.All substances on the earth are potential sources of atmospheric contaminants. Combustible materials (particularly fuel for heating and power), sea water, earth or soil, metals, and animals (including man) are some of the important sources of contaminants.Ordinarily gases are produced by chemical processes, whereas dispersoids are produced by both chemical and physical processes. There are two general dispersoid-producing processes: (1) Condensation, in which molecules join to form larger units or particles, and (2) disintegration, in which large units are reduced to the particulate range (which for the purpose of this article may be considered to be from 100 microns, or 1/254 inch, down to molecular size) by such processes as crushing, grinding, abrading, and atomizing.“Condensoid"" is a convenient term for dispersoids formed by condensation, and ""disintegrasoid"" for those formed by disintegration. Solid condensoids are sometimes called ""fume,"" solid disintegrasoids ""dust,"" liquid condensoids ""fog,"" and liquid disintegrasoids ""mist.""5/"

May 1, 1942

By Raymond B. Ladoo

In order to obtain comprehensive and authentic information on fluorspar mining in the western States , the writer, together with and at the request of representatives of some of the largest fluorspar producers of the Illinois - Kentucky district , spent the month of April , 1922 , in examining all we stem fluorspar deposits ( of which record was available ) believed to be of possible commercial importance .

May 1, 1923

By P. R. Jones

A computer program was written for the design of a shell and tube type heat exchanger on a price optimum basis. The program was designed to meet the following requirements: (1) Triangular pitch; (2) single or multiple pass; (3) heating or cooling; and (4) no change in phase. Price optimum design was obtained for four standard tube sizes and standard pitch. Pressure drop both inside and outside were computed and the nearest standard shells having at least the required area were listed. With this information, the estimator can select the heat exchanger best suited for the need. The program was made adaptable to various fluids and to various tube sizes and spacing by reading in much of the required data such as physical properties of the fluids, tube data, and standard shell data in tabular form.

Jan 1, 1967

By F. W. Wood

ORIGINAL experimentation in specially designed arc-melting furnaces and a comprehensive review of technical literature have helped with an understanding of electric arcs as used in metallurgical applications. Results relevant to the distribution of electric potentials and currents, temperatures, pressures, the consumption of electrodes, the identities of particles participating in electrical conduction, and the modes and mechanisms of discharge are presented and discussed. Present knowledge of high-current arcs is insufficient to test pertinent theoretical suggestions. However, the chief doubts concern the identities and the liberation or formation of current-carrying particles. It seems that either (1) novel formulations of existing concepts are needed, or (2) essentially new concepts must be recognized to explain observations. An analysis of the situation has led the authors to favor the latter possibility and to suggest the existence of supplementary conducting particles. The conduction of current by the streaming of charged agglomerates is postulated. Another outgrowth of analysis is an equation for the arc potential as a function of current densities in the arc. In lieu of conclusions, the potentialities of practical applications and specific needs for fundamental clarification are summarized.

Jan 1, 1965

By D. A. Baker, E. A. Gyawu, K. Awuah-Offei

Several underground coal mining disasters, such as Upper Big Branch in 2010, have revealed technological and organizational shortcomings related to self-escape. Efforts to address these gaps have primarily been top-down, that is, identified and implemented by upper management or external governing bodies. In contrast, this study employs a novel miner-centered approach to identify perceived technological boundaries to self-escape. Using a semi-structured, scenario-based survey, we elicit direct feedback from miners about current, emerging, and hypothetical technologies aimed at improving self-escape during mine emergencies. The results show a general high usefulness rating across all 21 technologies in the survey. Miners who work underground (both outby and working face miners) appear to give higher usefulness ratings overall than miners on the surface and other locations. This work will be directly applied to a series of proof of concept and prototype studies on self-contained self-rescuers (SCSRs), refuge alternatives (RA), and communication devises aimed at improving self-escape technologies through miner-centered research and design.

Mar 2, 2022

By G. Chahal, L. C. So, S. Faucher, S. Mostaghel, S. -Y. Oh, S. K. Lee

Slag dumping and water granulation are the most commonly used slag treatment methods in the metallurgical industries. In both processes, water is present (by desire for cooling and dispersion or as a result of rain accumulation) and thus equipment and operations are designed to minimize and mitigate the risk of steam explosions resulting from the inappropriate contact of slag with water. Slag handling practices have, therefore, never been inherently safe; even good design, operation, and maintenance are not sufficient to prevent explosions or other related injuries from occurring. For slag handling to become inherently safe, our industry must eliminate the potential contact of water with molten slag. This is today feasible with the advent of dry granulation technologies, a review of which is presented, and it thus falls to us, in the metallurgical sector, to lead the way in their final stages of development and adoption. Furthermore, while slag dumping and water granulation offer some metallurgists the means of valorizing their slag as a by-product, for most, this is not the case. The energy in slag is lost through dumping and water granulation processes, and where slag is sold as a by-product, it is for its chemical content only. Here, dry granulation processes also offer advantages including the production of by-products which hold value in both their chemical content and physical properties and heat recovery. Dry granulation, therefore, augments the methods by which slag may be valorized over traditional processing methods.

Jan 1, 2015

By James J. Olson

Most of the projects summarized in this paper are funded under the Bureau's Advancing Metal-Nonmetal Mining Technology program and are part of the in situ mining subprogram coordinated at the Twin Cities Mining Research Center. The borehole mining equipment development, are funded under the Bureau's Advancing Coal Mining Technology program, is essential to accelerated progress in the in situ mining subprogram, and some background information on this concept is included. The initial in situ research projects started in 1971-72 evaluated some of the critical blast design parameters for in situ copper leaching. The present program totals about $1 million per year and includes in-house research projects, cooperative (cost-sharing) projects with the mining industry, and research and development contracts. Two different extraction schemes are under investigation: inplace leaching and borehole (or slurry) mining. The principal commodity targets for the Bureau's improved in situ mining technologies include copper, uranium, coal, and potash. The principal purpose of this paper is to inform the mining industry of the in situ mining research recently completed or being conducted by the Bureau of Mines. In addition the Bureau encourages companies to comment on the program accomplishments as well as offer suggestions on top priority research needs for improving the in situ mining methods described in this paper.

Jan 1, 1977

By Alice V. Peter

The rare-earth group are among the least familiar of the 92 known elements. Moreover, the relatively few people who have even heard of the rare earths ordinarily regard them merely as very rare elements having unusual names but doubtful commercial application. This typical attitude can be attributed partly to the fact that no commercial uses have been developed for most of the members of the group and partly to the fact that those which do enter into useful articles do so anonymously. Most people speak with a degree of familiarity of the "chromium" plating on their automobiles or household appliances; "antimony" ash trays and cigarette boxes are on sale in many department stores; and "tungsten" lamps and even "molybdenum" steels are advertised in popular magazines. However, the average user of a pocket cigarette lighter is not conscious that the important sparking element is a "flint" made from ferrocerium, and if he does chap on to inquire about the composition he is likely to be told that it is "sparking alloy", "misch metal", or 'pyrophoric alloy." Similarly, the wearer of spectacles made of "Crookes" or other tinted glass probably is not aware that the light softening effects are due to the presence of rare-earth oxides, or that the arc light on his street may owe its brilliance to cerium fluoride in the carbon electrode. Despite a variety of practical applications, however, most of the rare-earth metals still must be listed as scientific curiosities. In fact, little is known as to the properties which may make them useful products at some future date. Meanwhile it is important to note that Nature has been relatively generous in her distribution of the rare earths and that adequate supplies of most of them will be forthcoming when these elements have proved their worth as commercial products.

Jan 1, 1935

By S Wilkinson, S Black, L van den Berg

"The mine ventilation system plays an important role in mitigating human exposure to diesel particulate emissions (DPM), exhaust gases and heat in underground mines. The mine’s secondary ventilation systems are critical for diluting contaminants when working at the face of a heading. To improve these systems it is important to understand and visualise the localised air flow profiles. We have considered an approach that includes both tracer gas measurement–modelling to analyse this complex flow behaviour in a heading. The use of tracer gas enables reliable measurements of flow behaviour and differentiation between the contributions of various contaminant sources including DPM. A pilot study was conducted to demonstrate how tracer gas can be used to directly measure the effectiveness of ventilation dilution in a heading during shotcrete activity. This activity is considered to be one of the more challenging areas for diesel exhaust exposure management. Exposure sources include the diesel engine of the spraying equipment (Spraymech) and concrete agitator truck (Agi) that supplies the shotcrete. During operation both the Spraymech and Agi operators are located outside the equipment’s air-conditioned cabins and both are exposed to diesel exhaust. In the pilot study tracer gas was injected directly into the Spraymech exhaust stream. This allowed thorough mixing, ensuring the tracer gas was able to track exhaust gases and particulates released to the heading. The release was repeated at three different headings with varying degrees of secondary ventilation controls. The study showed that small changes to the secondary ventilation system can significantly impact the contaminant concentration. It also demonstrated that tracer gas can be used to isolate different contaminant sources. The intent is to use this technique in a more comprehensive study to develop best practice guidelines for secondary ventilation installations. This paper presents the technique used and the preliminary results from the pilot study. CITATION: Wilkinson, S, van den Berg, L and Black, S, 2015. Application of tracer gas flow profiling to improve secondary ventilation practice – a pilot study, in Proceedings The Australian Mine Ventilation Conference, pp 345–352 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015

By T. G. Ewart

INTRODUCTION FOR THE purpose of this paper, western bituminous coal is defined as steam coal produced in Alberta and southeastern British Columbia for sale primarily to railways and industries. Before examining present and future markets of this industry, it is proper to review briefly financial and operating conditions within the industry. The report of the Royal Commission on Coal, 1946, supplies financial data from which some conclusions may be drawn. In 1944, the industry as defined above had share capital of $24,886,696. In the fifteen years 1930 to 1944, inclusive, the industry produced: 44,364,211 tons of coal. The profit on this tonnage amounted to $4,678,382.58, which represented 10.6 cents per ton of production. Miscellaneous earnings increased the amount available for dividends to shareholders to a total of $8,487,952.41, which is equal to, 19.1 cents per ton of production. Dividends actually paid in this fifteen-year period amounted to $12,332,040.64, which represented an annual average rate of 3.40 per cent on share capital. It is worthy of note that, in 1944, the net current position of the industry, including investments, was $8,753,874.51. The writer believes that the financial position of the industry with respect to capital, current financial position, and net earnings, has not significantly changed from the fifteen-year period out-lined above. The figures quoted indicate the following situation: (1) The western bituminous coal industry is adequately financed. (2) The industry has followed a conservative dividend policy and has accrued funds for contingencies. (3) The industry has sold its production at very reasonable prices as evidenced by its moderate earnings per ton of production.

Jan 1, 1951

By W. E. Crandall

The Star-Morning mine is a. 1000-ton-per-day lead-zinc producer located in the easterly part of the Coeur d'Alene Mining District of North Idaho. The property includes both the Star and Morning mines which are located on the westerly and easterly portions of the same complex of veins. The mine is 70% owned by the Bunker Hill Company (Gulf Resources, Inc.) of Kellogg, Idaho, 30% owned by Hecla Mining Company, and operated by Hecla Mining Company with head-quarters in Wallace, Idaho. One of the characteristics of mines in the Coeur d'Alene District is that many of the ore bodies extend to very great depths. The Star is no exception, but rather a leading example. The complex of near vertical veins and ore shoots extend some 7000 feet below the surface at present, with a maximum strike length of about 4000 feet. Ore has been mined on 20 separate veins and ore structures. More than 50 miles of headings have been driven and nearly 23 million tons of ore mined since the Morning mine started in.189S. The problems of mining at such depths are formidable temperature on the bottom level is 1100 F and high humidity problem. Pressure from the sheer weight of rock is as high foot. This paper will deal with providing a new access to the deeper levels of the mine and the installation of a hoist and related items to service these levels. By the time development had reached the 7100 level (Figure 1), it became apparent that a different 'hoisting system was going to be necessary if we were going to continue to mine at a profit. The main shaft extended to the 4000 level at which point a ?:3100"'foot winze shaft provided access to the 7100 level. The two hoists were limited to handling 3-ton payloads at 1200 to 1500 feet per minute. Some ores are still produced from above the 4000 level but as these ore reserves become depleted the hoisting of the desired tonnage (1000+/day-) from the lower levels of the mine would exceed the capacity of the existing hoisting system. A decision was made to sink a new vertical shaft at a point well in the south wall of the ore bodies where strong rocks and a minimum of faulting was expected and to purchase and install a new hoist capable of hoisting over 7000 feet. This new' shaft, designated as the No. 4 Shaft, was planned to reach 2000 feet below the 7100 level which was the deepest level at that time. The hoist would be in-stalled on the ,main 2000 Adit level which is used as an access and haulage level to the concentrator and surface plant in Burke.

Jan 1, 1971

By L. G. Wiseman

The raw materials processed, highlights of technology used, and products produced at INCO's Copper Cliff Nickel Refinery in Ontario, Canada, are described in this paper. INCO's Bessemer matte separation process yields various nickel and copper products and intermediates. The latter presents the main supply of raw materials for the Refinery. Key features in the Refinery are Top Blown Rotary Converters and the INCO Pressure Carbonyl (IPC) process. Process improvements made since the commissioning of the Refinery in 1973 are also discussed. The Refinery produces a variety of nickel products, including nickel powders. Residue after carbonylation presents an important intermediate enriched in precious metals and cobalt that serves as feed to downstream operations for recovery of the residue's metal values. Also discussed are detection, measurement and control procedures which ensure safe operation.

Jan 1, 1988

By K. L. Paciorek

The aim of the present study was to determine the thermal oxidative behavior of materials used in coal mines, with emphasis on the type and relative concentration of the products, in particular the toxic species formed. To supplement this work and to gain understanding as to the type of products possibly formed and also to assess the limitations and advantages of the various analytical methods used a literature survey of the past investigations performed on the compositions of direct interest to the subject program was conducted. The compositions thus covered were cellulose, polyvinyl chloride, neoprene, urethanes, polyamides, polyesters, polyethylene, epoxy, phenoxy, urea-formaldehyde and melamine formaldehyde resins. The results of this review are compiled in the Appendix. The experimental work consisted of thermal oxidative degradation of 36 materials and 4 composites using a stagnation burner apparatus developed in these laboratories which affords a dynamic system approximating somewhat the conditions encountered in underground coal mines. This technique as employed during this program gave only the relative product concentration at specific periods of the decomposition process, The advantage of this approach is that in this manner screening of materials can be accomplished in conjunction with some assessment of the decomposition rate as influenced by temperature and material composition. Limited static tests were performed using a sealed tube method. The materials studied were grouped according to their compositions. The following were the main groups: (a) polyvinyl chloride-containing materials, (b) neoprene compositions, (c) rigid foams (urethanes, isocyanates), (d) miscellaneous materials (including jute, fiberglass, polyethylene and some articles of unknown composition), (e) coal and fluids (phosphate esters, organic esters, oil-water emulsions), and finally (J) composites. The latter comprised a mixture of a phosphate ester fluid with (a) coal, (b) a representative polyvinyl chloride sample, and (c) a neoprene type composition.

Jan 1, 1972