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By John J. Sammarco

This report details the testing and evaluation of a modular azimuth and positioning system (MAPS) to provide navigational information for a continuous mining machine. Vehicle navigation is part of the U.S. Bureau of Mines research program in computer-assisted mining serving as a tool to increase mining health, safety, and productivity. The Bureau is investigating other navigation systems, but MAPS seems to have the most promise. MAPS was installed on a continuous mining machine. An operator used the machine to cut coal while researchers collected machine and MAPS data. A comparison of MAPS data for xy position and data obtained with an electronic transit showed an increasing error for MAPS. After 30 min of operation, the easting position error was -0.02 m, and the northing position error was 0.019 m; after 60 min of operation, the easting position error was -0.19 m, and the northing position error was -0.26 m. Modifications to MAPS software and to the operational procedure of the machine significantly reduced this error by a factor of 3.7. Researchers continue to reduce these errors.

Jan 1, 1993

By Edward C. Peterson

Recent studies indicate that the United States halt substantial reserves of ilmenite, one of the major titanium minerals. However, the studies showed that sources of rutile, another important source of titanium are limited. This paper summarizes and evaluates results and conclusions reached by the various investigations initiated by the Bureau of Mines and others pertaining to the titanium mineral resources of the Nation. Domestic occurrences of ilmenite that are economically exploitable by present-day beneficiation methods are found in Florida, New Jersey, New York, South Carolina, and Virginia. These deposits are estimated to contain 50.3 million tons of titanium dioxide (TiO2). Occurrences of ilmenite that cannot be processed economically under present technological conditions are found in California, Colorado, Minnesota, Montana, Oklahoma, Oregon, Rhode Island, and Wyoming. These reserves amount to 51.1 million tons of TiO2. Reserves of rutile found in the United States are estimated to be 1.8 to 2.1 million tons of TiO2. Other than occurrences in Florida and South Carolina, rutile is found either in small scattered bodies or in deposits where the mineral cannot be recovered economically by present beneficiation methods.

Jan 1, 1966

By Henry C. Knight

A number of improvements in the techniques of budgetary control have been developed in the 1970's. The most significant of these is zero-base budgeting. This procedure is a marked improvement, because it overcomes some of the key weaknesses inherent in most traditional approaches to budgeting. It incorporates techniques and disciplines which improve the quality of both the budgeting effort itself and the documents that most senior managers will need to evaluate. The end result is a budget that establishes and improves cost effectiveness. This budget is based on resource allocations using cost-benefit criteria and on a system of prioritization for making funding choices. Zero-base budgeting is applied only to costs and expenses that are not conducive to control using industrial engineered standards. Therefore, the benefits attributed to zero-base budgeting will only hold true for administrative, selling, exploration, safety, fire protection and overhead, and other indirect types of costs and expenses. It is in this context that the question of its attractiveness for the mining industry is dealt with.

Jan 1, 1978

By K. W. Morris

Of the fossil fuels used for power generation coal is by far the most variable and complex in its properties. A thorough review of the characteristics of the coal to be fired is essential before boiler design can begin. Major parameters such as heating value, moisture content and ash properties will determine not only the boiler size and configuration, but also the performance of the unit with respect to the thermal efficiency, particulate and gaseous emissions, and unit availability and reliability. An example of a review completed on a large low-rank coal deposit for a power plant will be described.

Jan 1, 1983

By J. D. Davis

THE carbonizing properties of one medium- and and five low-volatile coals from West Virginia and one high-volatile A and two medium-volatile coals from Pennsylvania were determined by 800° and 900° C. BM-AGA carbonization tests and expansion tests in the sole-heated oven. Plastic properties of the coals and the yields and quality of their cokes and other carbonization products were determined. The low-volatile coals comprised a mine and a coke-plant sample of Pocahontas No. 6-bed coal from the. Black Eagle No. 1 mine, Wyoming County, W. Va.; a mine sample of Pocahontas No. 6 bed from the Louisville mine, Mercer County, W. Va. ; Davy Sewell bed was sampled at the Twin Branch mine, McDowell County, W. Va.; and Fire Creek bed was sampled at the Dunedin No. 1 mine, Raleigh County, W. Va. The medium-volatile coals were from the Fire Creek bed, Laurel Creek mine, Greenbrier County, W. Va.; Lower Kittanning bed, Springfield No. 4 mine, Cambria County, Pa.; and Upper Kittanning bed, Springfield No. 6 mine, Clearfield County, Pa. The high-volatile A coal represented the Upper and Lower Freeport beds, Kent Nos. 1 and 2 mines, Indiana County, Pa. In addition to the coals listed, high-volatile A coal from the Pittsburgh bed, Warden mine, Allegheny County, Pa., a standard blending coal, was used in blends in this investigation.

Jan 1, 1950

By Vitor Fonseca de Barcelos, Jair Carlos Koppe

Our society is experiencing a digital revolution. Technology is demonstrating its significant potential for mining industry. In this paper are presented the measured and estimated impacts of applying new technologies on blasting operations in a copper mine.

Feb 1, 2020

By Immo H. Redeker

Introduction In October of 1961 Texas Gulf Sulphur Company contacted the Asheville Minerals Research Laboratory, of the North Carolina State University, and requested assistance in the development of a phosphate ore body in Beaufort County. The main: objectives of the work at Asheville were defined as follows. The Laboratory should try to determine on the basis of drill core samples, submitted by Texas Gulf Sulphur Company, the highest grade of phosphate concentrate that could be obtained with high recoveries from North Carolina ore, the thickness of the ore body that could be treated economically in one section, and the quantity of concentrate that could be obtained per acre. The results should be compared with data obtained from the treatment of Florida ores. It was important to use mineral preparation methods during the initial laboratory work that could be verified later by continuous pilot plant operation and could be scaled-up for a commercial plant. The writer was in charge of the project at the Asheville Minerals Research Laboratory and participated in the development of one of North Carolina's greatest mineral resources from the first drill core examination to the production of the first poundage and tonnage quantities of flotation concentrates. The Lee Creek phosphate mine and mill was put in operation in early 1966 and can produce three million tons of phosphate concentrate a year. Sulfuric- acid, and phosphoric acid plant, diamonium phosphate plant and triple super phosphate plants came on stream in 1967; at that time they were the world's largest. Now that a phosphate industry has been established in the State, it]

Jan 1, 1971

By John C. Machisak

Injury data and experience, with related employment statistics, at coal mines in the United States for 1960 are presented in this publication under the following general sections: A General injury experience: Tables 1 to 6: Current data on number of injuries, decree of injury, frequency and severity rates, average severity, and related employment and production data by work location. B Selected injury experience: Tables 7 to 38: Current data on principal agencies of injuries, distribution of injuries by part of body injured, days of disability, extent of hand and machine loading, experience by employment and production groups, and various other operating factors and physical conditions related to the occurrence of injuries at the Nation?s coal mines.

Jan 1, 1962

By Eugene N. Cameron, Igor N. Sviatoslavsky, Harrison H. Schmitt, Gerald L. Kulcinski

The recent discovery of large amounts of helium-3, a valuable thermonuclear fuel, on the surface of the Moon has prompted engineers and scientists to examine the commercial attractiveness, thetechnological feasibility, and the environmental features of this important resource. The main feature of this fuel cycle is the low (˜ 1%) fraction of energy released in neutrons. Such low neutron fluxes result in important reductions in the amount of radioactivity, afterheat, and radiation damage in a fusion power plant. On the other hand, the high fraction of energy in charged particles and synchrotron radiation can be directly converted to electricity, resulting in very high efficiencies of electricity production (˜60.70%). It has been shown that there is 10 times more energy in He3 on the Moon than there ever was in fossil fuels (i.e., coal, oil, and gas) on the Earth. The techniques and equipment needed to extract the helium-3 have been examined and internationally acceptable mechanisms for the industrial development of this resource have been outlined. This paper expands on the financial, environmental, and technical aspects of the recovery of helium-3 for use in the 21st century.

Jan 1, 1990

By D. McCarthy

This paper discusses the process involved in developing an optimum method of treating and removing heavy metals from water that have leached out from the native rock -prior to discharge back into the environment. Also designed into the system is a manner to stabilize the metals removed as a precipitate, so that they can be disposed of as a non-hazardous waste.

Jan 1, 1992

By C. E. Fivaz

SYNOPSIS Tribute is paid to J.S. MacArthur and the Forrest brothers for their invention. The opinion is expressed that the successful application of their process, not only saved the gold-mining industry on the Witwatersrand from stag¬nation for an indefinite but probably prolonged period, but also made a major contribution to the economic growth of the country in the twentieth century. A background is given of the activities of prominent chemists who researched the solubility of gold in cyanide solution prior to the MacArthur-Forrest invention. An account is given of the invention and patenting of the cyanidation process, and of the golden rule that the patentees laid down for themselves, which came close to wrecking the invention. The South African gold-mining scene from the discovery of gold on the Witwatersrand in 1886 up to 1890 is sketched. An account is given of how, when unoxidized ores were first encountered, the recovery efficiency dropped alarmingly, gold shares were sold on an unprecedented scale, and doom and despondency seized the town of Johannesburg. The complete turnabout in the fortunes of the South African gold-mining industry after the introduction of the cyanidation process in 1890, the steady rate of increase in production after the Anglo-Boer War, and its effect on the South African economy are described. A brief look is taken at the effect of gold mining on secondary industry. The deportment of the gold that is not dissolved from the ore by the cyanidation process is illustrated. Some thoughts are expressed on what can be done to increase the gold recovered by cyanidation.

Jan 1, 1988

One of the responsibilities of the Melbourne and Metropolitan Board of Works is to provide a sewerage system for the metropolis of Melbourne which now contains over 2.5 million people. In providing this sewerage system it was necessary for the Board to embark on a large tunnelling programme some 20 years ago. As a result of this extensive tunnel construction programme, tunnel boring machines and shaft sinking methods have been developed to cope with the soft ground and soft to medium rock found in the southern and eastern areas of Melbourne where the majority of the recent tunnelling has been carried out. While in the last few years radical changes in construction methods have not been made, development has continued and improvements have been made, which have enabled the Board to extend the limits of the ground conditions in which it can efficiently construct shafts and also tunnels with boring Machines.

Jan 1, 1976

By G. Reuben Yourt

IN 1935, Wright-Hargreaves Mines, Limited, initiated an enlarged programme of ventilation. In the mine, surveys were made from time to time by the geological staff, and improvements in ventilation were effected to accord with progress in mining as greater depth was attained. In the summer of 1938 an engineer was trained in the technique of dust sampling. Instruments and equipment for this purpose, such as konimeter, microscope, furnace, etc., were purchased, and a suitable office, equipped with laboratory facilities, was provided. The full time of the engineer is devoted to ventilation and dust control. On surface, in the mill crushing-plant and in the assay office and sample crushing room, an elaborate arrangement of hoods and exhaust systems has been installed to eliminate the dust. These installations, however, are not described in the present paper, which deals only with an extensive programme of underground ventilation as a method of coping with high dust concentrations, increasing temperatures and high humilities.

Jan 1, 1940

By P. G. Kovalchik

Recent research conducted by NIOSH, Pittsburgh Research Laboratory showed that electrical current levels permitted under present regulations may not limit cable temperatures to less than 90°C in reeled trailing cables. Reeled cables, tightly wrapped with many turns, all carrying current in an enclosed space, can become overheated due to poor heat transfer. This overheating can cause the cable insulation to soften and become easily damaged. The damaged insulation reduces the life of the cable and can lead to shock, electrocution, and mine fires. This paper describes a method of measuring the conductor temperature of mine trailing cables during normal operation. The temperature is measured using a 50/125 micrometer Graded Index Multimode Optical Fiber located in the center of the metallic conductors. Distributed temperature measurements are made using an Optical Time Domain Reflectometer (OTDR). This system is capable of measuring temperature with an accuracy of plus or minus one degree centigrade over a length of 4 km at 1-m intervals. With this unique way of measuring temperature, tests can be conducted simulating actual mine conditions and provide important data to allow MSHA's Approval and Certification Center to develop approval criteria for cyclically rated reeled machines.

Jan 1, 1998

By Thomas Varley

IN THE congressional act establishing the Bureau of Mines one of the functions outlined was "to assist I the industry in the prevention of mineral waste." This had not only to do with the waste in mining but in milling and metallurgical practices, including smelting. The organization of the Bureau of 'Mines includes many divisions, each working in a particular field and charged with certain investigative work. The metallurgical division has the above duties under its immediate supervision, and the station located at Salt Lake City is directed by the chief of this division: There are ten experiment stations of the Bureau of Mines, located in various parts of the country, most of them being housed at state universities under cooperative agreements. Considerable care was exercised in locating the stations and in choosing the particular type of work to be investigated at each place. Inasmuch as the Bureau was designed to serve and cooperate with the industry it is only natural that the investigative work be of interest and importance to the territory immediately adjacent to the respective stations.

Jan 1, 1925

By L. Rodd, C. Walker, T. Koehler

"The energy content of slag represents approximately 80% of the total energy inputs to a laterite nickel electric smelting furnace. Conventional slag handling methods produce only low grade heat and the entire thermal content of the slag is wasted. A heat recovery system proven on BOF slag in the mid 1980's can be adapted to a laterite nickel rotary kiln electric furnace (RKEF) plant. Slag is granulated using a high velocity air jet inside a waste heat boiler to produce slag granules. Granules are cooled during flight via radiation to water-cooled boiler walls and by convection to the granulation air. This system has the potential to recover 80% of the total slag energy in the form of hot air and steam.Integration of the recovered slag energy into the RKEF smelter can be achieved by a number of methods, including the use of preheated air at the ore dryers, kiln or existing power plant. Energy from the slag boiler may be used to reheat boiler feed water from the power plant or to produce superheated steam and generate electricity. The heat recovery system can provide up to 25 - 30% of the total electrical requirement of each RKEF line and a reduction in CO2 emissions of 234,000 tonnes per year.The total cost of slag heat recovery, including CAPEX and OPEX, is $2.5/GJ, which is competitive with using coal when CO2 credits are $18 per tonne. With Clean Development Mechanism (CDM) carbon credits currently selling at €13 ($20 USD) per tonne CO2, there is considerable opportunity for slag producers in regions including South America, Korea, Indonesia and Africa. Increasing fuel costs and more wide-spread legislation for GHG emissions will likely create conditions in which slag heat recovery could generate a favourable return on investment."

Jan 1, 2010

By Desmond Y. M. Lee

This paper presents a procedure to prepare input for the computerized pit design system at Iron Ore Company of Canada. The procedure is simple and requires very little training. Also, it is general enough to accept both bench (horizontal cross section) maps and section (vertical cross section) maps. The output of this procedure is data which represent blocks of ore and waste with dollar values based on mineral content. The ultimate pit design is presented in printer-generated graphs, with numbers indicating the depths of pit bottom walls. Roads are added manually by the engineer with the aid of other computer programs. Section maps and bench maps are also printed as part of the output of the ultimate pit design.

Jan 1, 1978

By Charles Janin

(San Francisco Meeting, October, 1911.) THE first successful bucket-elevator dredge to operate in California was put in commission at Oroville in March, 1898. There had been numerous previous attempts at dredging, but none of the earlier boats proved a success. The gold-miners in California early conceived the idea of a machine to dig gravel from the beds and bars of auriferous streams that were inaccessible by the methods then employed, and it was only a few months after the discovery of gold in California that such a machine was. shipped around Cape Horn from New York to San Francisco. This was, however, but the forerunner of many failures in gold-dredging, and was soon at the bottom of the Sacramento river. During succeeding years many other unsuccessful attempts were made, and it was not until 1897 that a dredge of the single-lift bucket-elevator type was floated on the Yuba river. This dredge was built by the Risdon Iron Works for R. H. Postlethwaite, and would probably have been a success if it had been operated on some of the rich Oroville ground instead of in a turbulent stream, where the dredge was wrecked during a flood, and was not repaired. Fig. 1 is a sketch-map of California, showing gold-dredging areas. It is not my intention to narrate in detail the history of the early failures in gold-dredging, and the various steps in the development of the modern boat, but merely to touch upon this in a general way, and to call attention to the wide difference in capacity and operating-cost between the first successful dredge, with an actual capacity of 600 cu. yd. per day-though its rated capacity was in excess of this-and the present modern dredge with 15-cu. ft. buckets, and an average capacity of 250,000 cu. .yd. per month. Even this enormous capacity has several times been exceeded on monthly runs. The first successful dredges

Mar 1, 1912

By J. J. Jonas, G. R. Stewart, N. Pokutylowicz, S. Yue, R. Varano, A. Elwazri

Differing thermal histories in and around a weld can lead to differences in grain size, phase composition and morphology of precipitates; mechanical properties will vary accordingly. Hardness testing gives limited information and the machining and testing of tensile and/or impact specimens that would reveal these variations (which may occur over very small distances) is not practical. Therefore, in this investigation, shear punch testing was applied to measure the variation in the room temperature mechanical properties of a welded pipeline steel.

Jan 1, 2005

By Rodney Clary

Building on work completed in earlier papers, the current paper presents a techno-economic evaluation of two recently demonstrated technologies for treatment of arsenic containing refractory gold concentrates. Using defined project parameters and inputs, the authors compare capital and operating cost estimates for pressure oxidation (POx), and the Albion Process™. The paper incorporates data now publicly available from the Albion Process™ plant, which has operated at the GeoProMining Gold (GPM Gold) project in Armenia since 2014, as well as recent POx circuits.