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By V. V. Morozov, Ganbaatar Zorigt, Delgerbat Lodoy, Y. P. Morozov

"At the processing plant Erdenet, a new facility for advanced ore diagnostics in-stream (at the conveyor), based on optical analyser of mineral composition, was tested. Such systems provide highly accurate in-stream measurements of ore properties. The system provided information on the ore mineralogical composition, the particle size distribution and the impregnation of minerals. A special flatbed facility for optical spectrum-based estimation of fine-crushed ore has been developed, being incorporated into the existing system of ore sampling and analysis. Application of the flatbed facility renders possible a high accuracy of determining ore mineralogical composition. High precision of the optical spectrum-based estimation is achieved using special devices, installed in the sampling and the sample analysis flow sheet, applied by the technical control department. Modern systems for optical spectrum-based estimation of ore grade provide a basis for effective automated control of ore benefication processes, based on the principle of advanced ore grade control. Process management task of grinding and flotation was to choose options that take into account the composition and grade of the ore coming. The calculation data array comprises consumption of reagents, ore processing, grind size etc. The systems implemented at the processing plant contributed to increasing copper and molybdenum recovery. INTRODUCTION In-stream ore grade analysis is a new trend in effective control of ore benefication processes. This is realised based on radiometric measurements in the X-ray and visible spectrum regions, in which mineral components of the initial ore (Sbárbaro and Villar, 2010) or the benefication products become apparent (Hyotyniemi and Ylinen, 1998; Haavisto and Hyötyniemi, 2010). An important advantage of such methods is in-stream measuring ore parameters, including mass fractions of individual minerals, which makes it possible to use the information obtained in the processes of automated control."

Jan 1, 2018

By Michael Magerstädt

Material loss by abrasion of contact surfaces of pipes, chutes, pumps, and other equipment in contact with ore is one of the main reasons for downtime of mining operations. Abrasion protection materials in use range from expensive tungsten carbide overlay to hardened steels, ceramics, as well as polymers, particularly polyurethanes (PUR). This paper describes abrasion protection products made from High Performance Polyurethane Elastomers. An interior pipe coating was developed that exhibited outstanding abrasion resistance and an extremely high adhesion to steel. Years of field testing in oil sands tailings as well as applications in slurry lines (e.g., phosphate slurries) have proven the performance of this material. A proprietary field joining process was developed and successfully applied in the field. This joining process requires only one field weld per joint very similar to the joining of uncoated pipe. No internal re-coating is necessary adding savings during pipe laying to the significant savings of reduced down time. Using the building-kit chemistry of polyurethane synthesis, similar high performance elastomers were used to extend the life time of ball mills. An intelligent system was developed in which wear parts contain sensors reporting the actual wear thereby optimizing maintenance interval leading to significant cost savings for the operator. Test data as well as field experience with High Performance PUR Elastomers for abrasion protection in mining are presented.

Aug 1, 2013

By Rolfe PR, Ellis BA, Clements RJ

Associated Minerals Consolidated Limited (AMC) is constructing a 112,500 tonne/yr synthetic rutile plant at Narngulu, near Geraldton in Western Australia. Design of the plant is based on the technology developed by AMC and utilised in its two existing plants at Capel in Western Australia. Ilmenite Feedstock for the plant will be sourced from AMC's mine at Eneabba and coal obtained from the Collie deposits. The plant is scheduled to come on stream in the second quarter of calendar 1987. The rationale of the decision to construct the Narngulu plant is examined against the background of the world market for high-Ti02 content feedstocks. Also provided is a detailed description of the plant and an examination of the technology used in process Design.

Jan 1, 1986

By Paul Hatmaker

Pumice and pumicite are siliceous volcanic substances quite similar in chemical composition , but somewhat different in physical properties , manner of formation , and mode of occurrence . Production in the United States has increased from 23,271 tons valued at $ 94,943 in 1910 , to 56,843 tons valued at $336,099 in 1930. Both pumice and pumicite are included in these figures as it has been impractical to collect statistical data on the separate commodities .

Mar 1, 1932

By Dinesh Goyal

Industrial fly ash from (electro static precipitator) was mixed with soil at different levels on v/v basis for raising of pulpwood tree species. In field trials conducted on degraded soils increase in the plant growth of Eucalyptus tereticornis, Acacia auriculiformis and Casuarina equisetifolia by 10 %, was observed during the initial six months after plantation at 18-24% (v/v) fly ash concentration which was at par with chemical fertilizer treatment. Level of As, Se and Mo in flyash was 6.2, 3.6 and 4.0 ppm respectively. The radioactivity analyses 40K, soil and 28 fly ash showed that the activity levels of gamma emitting radionuclides K, Ra, Ac were within the permissible limits and mixing of fly ash with soil at tested concentration would have no deleterious effects. Available Co, Cr, Ni and Cd in rhizospheric soils were below detection limit. Fly ash at 10-20 % level (v/v) was also found to be a good potting mix material in forestry nurseries in terms of improving biomass production by 20 %, when tested in nursery seedlings of Eucalyptus tereticornis. Nursery addition of fly ash in soil decreased soil dehydrogenase activity and the soil bacterial population was negatively affected. These results indicate that use of fly ash in forestry sector involving nursery and plantations as a soil amendment agent upto 10-20 % v/v is a gainful utilisation of fly ash.

Jan 1, 2002

By K. W. Nelson, John N. Abersold

INDUSTRIAL hygiene has been defined by Patty' as "the science and art of recognizing, evaluating, and controlling potentially harmful factors in the industrial environment." This definition implies thorough study of operations, evaluation of potentially harmful factors through air sampling, micro-analyses and other means and finally, appropriate medical and engineering control wherever indicated. The prevention of industrial health injuries is a vital part of operations of American industry today. Progress and interest in this field has increased steadily for many years, the most rapid progress having been attained, perhaps, during the last three decades. It is significant to note that there are now official agencies in 46 states actively concerned with industrial health problems and that a western field station has been established recently in Salt Lake City by the U. S. Public Health Service to augment its industrial hygiene services directed from headquarters of the National Institute of Health, Bethesda, Md. Many of the larger industries have found it advantageous to establish their own industrial hygiene departments. The American Smelting and Refining Co. is a world-wide organization engaged in the mining, smelting, and refining of lead, copper, zinc, silver, gold, by-product metals, including cadmium, arsenic, and others. In the United States there are 13 smelters and refineries, 11 secondary smelters or foundries, and a number of mines. Approximately 9000 workers are normally employed. It has long been the established company policy to seek out occupational hazards and provide safeguards for employee health. Protective equipment has been supplied to individual workers and exhaust ventilation installations have been in use in some operations for more than 40 years. All of the major units have their own medical departments which provide employees with excellent medical and hospital care. In 1937 full scale industrial hygiene studies were undertaken at the Selby Plant and were extended to most of the other smelters during the next three years. In 1945 the Department of Hygiene was organized with Professor Philip Drinker of Harvard University as Director and with Dr. S. S. Pinto as Medical Director. The department is responsible for coordinating and maintaining a program for the good health of all employees from top management down to the lowest paid day worker. It is essentially a service organization serving all of the United States plants regardless of location or size. Full and part-time physicians employed in all of the company's American plants and working in close cooperation with the Medical Director are responsible for de- termining the state of health of all the employees and giving treatment when necessary. In general, medical care is confined to accidents or illnesses occurring while the men are on the job. Among the duties of the doctors is the making of careful physical examinations of new employees and routine check-ups of old employees. In addition to medical care a primary responsibility of the department is the prevention of occupational illnesses. In this the main concern is with the working environment in relation to its effect on the worker. Environmental factors may be dusts, fumes, gases, toxic materials, heat, humidity, radiation, or noise. The objectives are: (1) Immediate control of these factors through the education of the worker, through providing the wearing of respirators or other protective devices, and through careful medical examinations and regular analysis of urine specimens; (2) a long range control program which may be accomplished by local exhaust ventilation, wetting of materials, changes in metallurgy, changes in methods of handling, or by use of special devices and special equipment. To accomplish these objectives a fine industrial hygiene laboratory was built in Salt Lake City and equipped to do routine and experimental work. Trained and experienced industrial hygienists obtain the facts by making frequent hygiene surveys. These surveys include tests of the air, studies of all processes, and careful investigation of ventilation, lighting, and general working conditions. Except in emergencies, the air contaminants and often the substances handled by the worker are sent to the laboratory for analysis by chemists and technicians specially trained in industrial hygiene methods. The findings are evaluated in terms of limits recommended by various State and Federal agencies, and in light of all available medical data. The methods used for studying the working environment involve all of the usual chemical and physical procedures employed in industrial hygiene. The Impinger, electric precipitator, thermal pre-cipitator, and filter paper sampler have been used to collect atmospheric dust and fume samples. Of special interest here is the filter paper sampler, shown in Fig. 1, which was developed by Dr. Silver-man at Harvard University. The instrument has been improved and is used very extensively in field studies. A water manometer connected behind an orifice is used to determine the rate of air flow. Calibration is effected by use of a standard gas meter or rotameter. The dust or fume is collected on a filter paper clamped between two rings, as shown in Fig. 2. The filter paper, such as Whatman No. 52, collects both dust and fume with a very high efficiency. The instrument is very convenient and easily transported. The solids collected on the filter paper are analyzed in the laboratory usually by use of a polar-ographic procedure. By this procedure it is possible to measure quantitatively in a single analysis the

Jan 1, 1952

By Charles H. Parr

A testing program was conducted to determine the suitability and reliability of adhesives and polycarbonate lenses for extended use in luminaires in mine environments. Polycarbonates were exposed, for periods up to 36 months, to four environments including ultraviolet light, humidity, intermittent water spray, and heat of either 180°F or 407 in various combinations. Rod impact tests on the exposed lens material indicated, that polycarbonate functions well under all 180°F environments and could be used with confidence for periods exceeding the test period, for as long as ten years, with a suit) able safety factor employed in design. The specimens exposed at 240°F showed decreased toughness after 24 months' exposure. Extrapolation of these data was deemed to be risky. A 462-day compatibility test between polycarbonate and six hydraulic fluids was run on stressed PC beams. One fluid caused beam breakage in less than one day, while three caused breakage at intermediate times. Two fluids exhibited essentially no effect on the PC when compared to a control. Epoxy and silicone adhesives were tested as lens adhesives and sealants. Three epoxy combinations tested showed low and erratic failure stresses. A room-temperature-cure silicone adhesive functioned extremely well for time periods up to 36 months and temperatures u2 to 240°F.

Jan 1, 1985

By Oliver Bowles

The exingencies of a world war have brought home to the American public, especially the people of the. Eastern States, the urgent need for conserving fuel. Transportation problems in the East have created an unprecedented situation wherein fuel-oil supplies are greatly restricted, and the consequent increase in demand for coal further complicates the problem of transporting and storing that commodity. People should awaken to the need for utilizing every possibly means of conserving to fuel, even to the extent of reducing the temperature in their homes.

Jan 1, 1942

By E. J. Lintner

This paper is one of a series being prepared by the United States Bureau of Mines describing clay mining, crushing and grinding methods, and costs at various clay-mining operations throughout the United States. These papers are designed to disseminate technical information regarding methods used. The cost tabulations represent local operating expenditures only and not total production costs. Although the publication of total production costs might not be advisable in some instances, yet a knowledge of operating costs is essential to the technical discussion and study of the methods employed. The attention of the reader is specifically called to-this distinction between total and operating costs in order that no misunderstanding of the cost tabulations shall ensue. The following report deals specifically with the methods employed by the Dennison Sewer Pipe Co., Dennison, Tuscarawas County, Ohio.

Jan 1, 1936

By V. E. Edlund

Pyrometallurgical studies by the Bureau of Mines demonstrated the feasibllity of sintering and smelting a low-grade flotation concentrate made by pilot-plant processing 10-percent manganese ore from the Maggie Canyon deposit, Mohave County, Ariz. Under optimum conditions 85 percent of the manganese in a flotation concentrate that assayed 36 percent manganese was recovered as standard ferromanganese. A blend of this flotation concentrate with high-grade dithionate pilot plant precipitate was similarly processed with a recovery of 90 percent of the manganese. Thorough mixing and pelletizing of the charge before treatment on the sinter hearth was necessary to produce a well agglomerated product by single pass sintering. Although satisfactory sinter was produced from a variety of material combinations, best results were obtained on a charge that contained 80 percent flotation concentrate and 20 percent return sinter fines. This combination was mixed with 6 percent coke, based on weight of concentrate; and 12 percent moisture. Sintering such a charge yielded a well agglomerated product containing over 80 percent coarse material, The results of standard crushing tests showed that the product was physically comparable to iron ore sinters and manganese nodules.

Jan 1, 1962

By M. J. Beus

Researchers at the U.S. Bureau of Mines have developed personal-computer-based data acquisition, instrumentation, and mine visualization and modeling techniques to evaluate a mine accessway in a deep hard-rock mine in northern Idaho. These techniques were applied to a mine shaft in a large silver mine that has been in operation for many years. A very deep, rectangular, timber-supported shaft extending to depths exceeding 2.3 km (7,500 ft) had been deforming continuously as a result of nearby mining, resulting in operational problems. Preliminary visual observations and rock and support monitoring confirmed that severe diagonal distortion was occurring. Extensive field measurements and data analysis confirmed initial observations, provided insights into the cause of deformation, and defined a general approach to structural modeling. Computer analysis of the problem was initiated by developing a three-dimensional model of the terrain. This represented a volume of rock approximately 80 km3 (40 x 1010 ft3) and an area on the surface surrounding the mine 9 km2 (3 square miles). Based on this model, a three-dimensional, finite- element analysis was conducted to establish boundary conditions for sequentially more detailed two- and three-dimensional submodels of the shaft area. Results from the computer study are being used to develop new approaches to mine design and to provide design guidelines for deep mine accessways subject to severe rock-mass loading conditions.

Jan 1, 2010

By Michael A. Trevits

The National Institute for Occupational Safety and Health (NIOSH) in partnership with Strata Products tested the sealing capability of Ventstop®? as part of an ongoing mine fire control and suppression research program. Ventstop®? is a multi-purpose, inflatable device that is produced by Minvent Solutions and is available world wide for use in the metal and nonmetal mining industry. Ventstop®? is also used in the Australian coal industry as a temporary ventilation control device. The device can be quickly deployed, is reusable and can be placed in horizontal and vertical mine voids to control dust, fumes and smoke. Deployment, multi-day inflation and air leakage tests were conducted at the NIOSH Lake Lynn Laboratory to determine the capability and limitations of Ventstop®? in a simulated coal mine setting. During the tests, Ventstop®? was also subjected to low level forces of a nearby methane gas ignition. It is thought that Ventstop®? could be used by the US coal mining industry to temporarily close an underground mine area in response to a fire or spontaneous combustion heating event, to temporarily redirect mine ventilation during longwall equipment moves or during stopping construction. This paper describes this inflatable temporary mine sealing technology and presents the results of the NIOSH tests. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of NIOSH.

Jan 1, 2009

By Irving Hartmann

The record of safety in the use of permissible explosives in United States coal mines has been excellent, due in great measure to the persistence with which research has been carried on in the Bureau of Mines, to the development of permissible explosives, and to the cooperation of mine operators and workers in using permissibles in a recommended manner and in the effective though gradual replacement of black powder and other nonpermissibles. The demand for increased rate of coal production, changes in mining conditions and minim methods, and introduction of new mining machinery have resulted in modified or new blasting practices. To keep abreast of these developments the Bureau of Mines conducts investigations under actual mining conditions at the Experimental coal mine near Pittsburgh, Pa. Several years ago an extensive study was complete to determine conditions under which the allowable charge limit for permissible explosives per shot hole might be raised from 1.5 to 3 pounds without undue risk of gas or coal-dust ignitions. As a result of the study, this increase in the charge limit was authorized under certain specified conditions in 1948,5/ greatly facilitating production schedules.

Jan 1, 1954

A combination of the needs of business, employee desires and safety and health considerations is stimulating increasing attention to the time spent by people at work and the timing of that work. Particularly we are seeing: - innovative work schedules for 24-hour mining businesses; and - response from industry to accommodate the needs, even the desires, of employees in return for systems which are more productive and more capital efficient. There appears to be an evolutionary trend for business management to become more sophisticated and responsive to the need for achieving close to best cost work schedules to sustain continuous improvement. The underlying motivating forces driving this trend for improved techniques in organising attendance at, and time spent at work, is the seemingly inseparable combination of technological advance and ever-increasing accumulation of capital. The mining industry has not remained untouched by this thrust for ever-increasing need for best use of labour, to adopt advances in technology and to provide attractive opportunities for putting accumulated capital to work. An essential component of this on-going thrust is a substantial effort by the mining industry to improve the performance of labour by providing most-productive work schedules.

Jan 1, 1996

By M. C. Harris

The past twenty to thirty years have seen unprecedented research activity aimed at understanding the performance of flotation froths. In 1990, Finch and Dobby coined the term froth recovery factor, Rr, to represent the efficiency of the froth in delivering particles from the pulp-froth interface to the concentrate. Originally defined for flotation columns, Rr has also been found useful in modeling mechanical flotation cells, and a number of techniques, based on quite different approaches, have been developed for measuring the froth recovery in industrial flotation cells. None of these techniques is universally successful. This paper reviews the concept of the froth recovery factor, and the basis of each of the techniques that have been proposed to measure Rr, and examines the reasons for this parameter being so difficult to pin down. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By John J. Mulligan

Coalbeds were discovered in outcroppings of the Beacon group of sediments on the north end of the Willett Range ( altitude 77 ° 11 ' S , longitude 160 ° 20 ' E ) , Victoria Land , Antarctica , in December 1960 during an investigation undertaken as part of the U.S. Antarctic Research Program under the auspices of the National Science Foundation . Three separate exposures of coal or coaly material were found . Two of the exposures contain , respectively , eight and four beds of hard , compact , finely banded attrital coal ranging in thickness from 8 feet downward to a few inches , and reported to range in rank from mediumvolatile bituminous to semianthracite . The coals are associated with carbonaceous shales containing an abundant assemblage of fossil plants resembling those associated with the Permian coals of Australia and other Gondwana areas . The third exposure , apparently somewhat higher in the stratigraphic sequence , contains only coaly plant fragments scattered through a thin conglomerate and overlying sandstones . A sandstone bed that overlies these coal - bearing sandstones contains abundant logs and fragments of silicified wood . Preservation of features is poor , but one segment of a silicified stem suggests comparison with Rhexoxylon , a gymnospermous tree that usually is considered indicative of Triassic age . The Beacon sediments in this area have been invaded , broken , and uplifted by a massive series of diabase sills and dikes greater in volume than the intruded sediments . The heat emitted by these intrusives must have advanced the metamorphic development of the coals . However , there is no evidence of alteration to graphite , and coal found in direct contact with a diabase sill contains no vesicles or other usual evidences of natural coking . Either the pressure of overlying rocks inhibited the development of coke , or the coals had been metamorphosed beyond the coke forming stage before the igneous intrusion .

Jan 1, 1963

C. D. Demond, Anaconda, Mont. (communication to the Secretary*) :—In order to throw some light on this interesting subject, a series of experiments were made with strips of mild steel, containing about 0.14 per cent. of C and 0.22 per cent. of Ma. These strips were thoroughly cleaned and brightened before use, salts were added to distilled water until it corresponded as nearly as possible to the analysis given by Mr. Lee, and in this water at different temperatures were placed four strips of steel; while four other strips, at corresponding temperatures, were placed in the water used at the Washoe Reduction Works. The latter plant has had no trouble from corrosion of furnace-jackets, pipe-lines or boilers. The analysis of the water used at the Washoe works is: Grains er U. S. Gallon. CaCO3........... 2.92 CaSO3........... 0.76 MgCI3........... 0.64 MgCO3........... 0.58 A1203........... 0.12 Fe2O3........... 0.12 SiO2........... 0.58 NaCl........... 0.35 Organic matter, etc.,........ 1.16 7.23 This water is neutral to litmus; while the artificial Copper Queen water was very slightly alkaline, which Mr. Lee informs us is also true of the water at Douglas. Both waters mere well aerated by pouring from beaker to beaker, and by blowing in air from the experimenter's lungs. The results of these tests, given in Table I., show that there is no significant difference between the effects of the two waters.

Jan 1, 1909

By A. A. Brant

Self-potential methods are based ?on measurements on the surface of voltage distributions caused by natural sub-surface oxidation phenomena. The attempt is made to. correlate voltage minima or maxima with the location of mineral materials or geological conditions which may give rise to such naturally produced spontaneous potentials. Any orebody undergoing oxidation is a source of electric current. Ground waters carrying free oxygen attack the upper surface of the body, rendering this the positive pole of a galvanic cell, with the lower portion of the body the negative pole and the surrounding weak acidic waters the electrolyte. Current flow is from positive to negative through the orebody and negative to positive through the electrolyte, i.e., through the surrounding rock. The upper end of a steeply dipping, tabular orebody is hence indicated as lying below the point on the surface where the largest negative potential is observed(l). From its basis, it is apparent that the self-potential method was developed primarily for ore exploration.

Jan 1, 1942

By J. H. Holden, G. R. Strimbeck, L. F. Willmott, W. R. Huff

A pilot - scale fluidized feeder was developed for continuously feeding up to 1 ton of pulverized coal per hour to a pressure gasifier . Fluidization in the 3 - foot - diameter by 34-1 / 2 - foot - high feeder is effected by two streams of inert gas , a technique called zone fluidization . A stream of inert gas through a drilled plate in the base of a central column near the bottom of the feeder fluidizes the coal . Another stream through a drilled plate in the annulus between the central column and feeder wall provides a source of semifluidized coal for the central column . Fluidized coal from the central column discharges through an extraction funnel and discharge line . Zone fluidization provided good fluidization with moderate requirement for fluidizing gas . Instruments were developed for metering and recording the flow rate of fluidized coal . A system was developed for storing , and weighing pulverized coal , and then delivering it in fluidized form at about 1 to 8 tons per hour .

Jan 1, 1964

By Unknown

We are indebted to the Consolidated Mining and Smelting Company of Canada Limited for the several pictures in this issue showing the progress made in new construction at Tadanac and at Bonnington Falls, B.C. Plate No. 1 shows the down-stream side of the No. 1 hydro-electric station of the West Kootenay Power and Light Co. Limited at Bonnington Falls, on the Kootenay river, at which 17,500 k.v.a. will be developed to meet the requirements of the enlarged zinc and lead refineries at Tadanac. The generators, exciters and switch apparatus were supplied by the Canadian General Electric Company and the step-up transformers by the Canadian Westinghouse Company Limited. The plant throughout was designed, manufactured and erected by Canadians. Plate No. 2 shows the casting room of the new lead-plant and plate No. 3 the new tank-room of the electrolytic lead refinery at Tadanac. These additions will increase the capacity of the lead refinery by some 150 tons daily. The extensions also include practically doubling the zinc plant, and the gold and silver refineries. With the exception of the new stack, all designing construction and installation of the various plants is being done by the Company's own employees at Tadanac. Plate No. 4 shows the progress made in the construction of the new reinforced concrete stack at Tadanac. This stack, of 21 feet inside diameter at the top, will be brick lined and when completed will rise 400 feet above its foundations: the tallest of its kind in the world. The construction is in charge of the Rust Engineering Company of Pittsburgh, Pa. Plate No. 5 is a panorama of the Tadanac smelters and refineries. The photograph was taken from the roof of the lead smelter and gives an excellent idea of the size of the plant and its surroundings. Tadanac produces electrolytic lead, zinc and copper and fine gold and silver. During 1924 the company treated 1,333,523 tons of ore and produced: 161,400,- 769 pounds of lead; 92,197,824 pounds of zinc; l,382,750pounds of copper; 4,074,044 ounces of silver, and 26,976 ounces of gold.

Jan 1, 1925