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By G. St. J. Perrott, N. A. Tolch

"The testing of explosives for permissibility for use in coal mines was begun by the technologic branch of the United States Geologic Survey in February, 1909, and continued by the United States Bureau of Mines from July, 1910; this testing has been carried on from year to year as the explosives were submitted by manufacturers. As a result of these many years of testing for permissibility a large amount of data has accumulated regarding the characteristics of permissible explosives. The manufacturer expects a sample of explosive submitted for test to meet the requirements for permissibility, otherwise the sample would not be submitted. However, in spite of the careful regulation and preparation of the formulas a certain percentage of explosives fails to pass the gallery tests. It is therefore interesting to note the proportion of failures at the gallery for a given composition of explosive. The fact should be emphasized that this discussion deals with all explosives submitted for test, both those which passed the tests and those which failed to pass. Explosives that failed to pass the tests were never designated as permissible explosives and have never appeared on any list of explosives permissible for use in coal mines.The Bureau of Mines classifies permissible explosives in two ways, according to the quantity of poisonous gases produced and according to the characteristic ingredient of the explosive.4 In this paper only two types of the latter classification are considered, as follows:"

Dec 1, 1929

By Zhang Yongzhu

Sulfoxides are one kind of extractants for precious metals. The structure, the coordination reaction, the extraction behaviour and the precious metals complexes of sulfoxides are summarized. The differences between sulfides, sulfoxides and sulphones are also discussed.

Jan 1, 1992

By S. Esfahani, M. Barati, Y. Kauwachi

"Heat recovery from slag has gained attention due to its high potential in lowering energy intensity of metal extraction processes. A direct method to recover the thermal energy of slag is to use countercurrent air flow that extracts the heat from falling droplets. Often, the solidified slag is aimed to be used as a substitute for Portland cement, thus high cooling rates are required to form an amorphous slag with sufficiently strong hydaulicity. Rapid cooling however involves using large gas flow rates that in turn lower the thermal efficiency of the process. This article presents a mathematical model that was developed to determine the optimum conditions in the heat recovery process and to investigate the effect of the air flow and granule diameter on the cooling rate of the droplets as well as the thermal efficiency of the heat recovery system. INTRODUCTIONMetallurgical slags are the largest by-product of high temperature materials refining and extraction processes. The total amount of metallurgical slag produced in the year 2008 has been estimated at up to 422 million tonnes containing up to 222 TWh/y (Barati and Esfahani, 2011) of thermal energy. Over the past four decades attempts have been made to recover this substantial amount of energy as heat, electricity, or fuel, while none of the proposed method has been commercialized yet.During slow cooling the slag tends to crystallize the constituents (CaO, SiO2, Al2O3, etc.) into a hard, heavy solid. In the past, over 90% (Bengt, 1983) of the molten waste was discharged onto heaps and allowed to cool slowly, then crushed and used in road construction or land filling or as coarse aggregate for concrete. However, later it was found if cooled rapidly, the slag can be used as a substitute for Portland cement. As a result, processes such as wet granulation were created in which molten slag is fragmented with water, forming amorphous (glassy) phases. Despite its effectiveness in producing a suitable material, heat would not be recovered through this process. Thus, dry granulation was introduced in 1930’s and was developed further in 1970 – 1980’s."

Jan 1, 2012

By Robert W. Bruhn

State and federal regulations require that surface mine overburden be investigated in advance of mining for naturally occurring earth materials that are detrimental to animal and plant life or to uses of water. Proper identification of these toxic materials is necessary to permit development of environmentally sound reclamation programs. Intensified use of present laboratory methods to meet anticipated testing demands would be both costly and time consuming. This paper discusses the desirability of and general requirements for a geophysical system capable of locating toxic zones in the overburden of surface mineable lands of the Northern Great Plains Coal Province. The paper (1) identifies the types and character of naturally occurring overburden substances that must be investigated in advance of mining, (2) discusses the economic justification for development of a geophysical system to replace or to complement conventional laboratory test methods, and (3) discusses the potential applicability of downhole geophysical methods to overburden analysis.

Jan 1, 1981

By A. A. Berk

In the course of a study of the formation of external deposits on tubes in water-tube boilers it became desirable to determine the sulfur dioxide (SO2) and sulfur trioxide (SO3) in the Due gases. Determinations made by the A.S.M.E. method for SO2 and SO3 in gaseous products of combustion did not give accurate results. It was found that minute quantities of copper, present in the flue gases from the coal in use, caused oxidation of sulfite in the absorption bottle and that the carbon dioxide (CO2) in the flue gases caused high values for SO2. The A.S.M.E. test procedure was revised to prevent oxidation of sulfite in the absorption bottle and to allow for the effect of CO2; subsequent analyses of flue gases produced reliable results. The revised procedure is described.

Jan 1, 1950

By C. Moctezuma

Since the start up of the IMMSA electrolytic zinc refinery in 1982, the dissolved iron coming from the acid attack of the ferrites has been precipitated by the jarosite process. At the beginning of operations, sodium jarosite was produced; however, the plant was converted to ammonium jarosite in 1990. The final storage of the residue is on the company&apos;s property adjacent to the plant, over the natural surface of the land. Before the construction of the refinery, several studies were done in order to evaluate the characteristics of the ground, such as, permeability, underground water localization, etc. The results showed that the site was adequate for the storage of this kind of material. For several years, the jarosite residue was filtered on rotary drum filters and was sent as a pulp to the storage area for settling. The water from the storage pond was recycled to the re-pulp tank for the jarosite residue. These filters were replaced in 1999 by an automated filter press. Since then, the jarosite residue has had a lower water content, and the zinc recovery improved. At present, a second filter press for the jarosite circuit is in the acquisition process to diminish the soluble zinc content in the residue from the present value of 2% to < 1% Zn.

Jan 1, 2006

By Eric Nordhausen

This report and associated deliverables is the culmination of a comprehensive literature survey, data collection and identification of over 500 metal/nonmetal active mines/mills/smelters (over 50,000 tons per year, TPY, production) in the contiguous 48 states. The main purpose was to compile an inventory of the mine/ mill/smelter waste tonnages, thus forming a data base for future research and development in improving waste management and waste disposal techniques in the metal/nonmetal mining industry. The study specifically excluded sand and gravel, sulfur, granite and any commodity that leaves basically no waste when mined and/or milled. The coal waste inventory is the subject of another report. The study provided for locating, mapping. encodating and digitizing all the mine/mill/smelter information made available throughout the nation as well as the climatological, land use, topographical, ecological and vegetative data. Mine/mill/smelter information also included (where possible) acreage and/or volume, mining methods, primary ore and gangue minerals, waste composition and haulage methods and distance hauled. Finally, a discussion is provided concerning present and potential uses of various types of tailings, as well 8S recommending possible R&D in addressing problem areas in waste disposal techniques and management.

Jan 1, 1981

By R. Stach, S. Gola, P. Zgrzebski, K. Soroko

"The future of Polish copper mines KGHM Polish Miedz S.A. will be associated with mining at depth. At present, technologically advanced measures are being introduced to minimize the adverse influence of the environmental hazards on people working underground. Polkowice-Sieroszowice mine is the only mine in Poland where mining takes place in copper and salt deposits. On the basis of the current and anticipated methods of ventilation of a selected ore deposits the paper will analynze a number of solutions enabling planned mining of copper ore deposit, while minimizing the impact of natural aerological hazards in working areas. INTRODUCTION The future of copper ore mining, carried out by KGHM Polska Miedz S.A., will be based on mining from continuously greater depths (Butra, 2015). It is forecast that this will be accompanied by an increasing climatic hazard, resulting from an increase in the original temperature of rocks of more than 45°C as well as gas and geodynamic hazards (Soroko, 2015; Andrusikiewicz, 2015). Due to the safety of underground teams, a need arises to develop methods eliminating the adverse impact of the natural hazards, down to a level enabling the mining activity to be carried out on an industrial scale while maintaining favourable economic parameters. Current depths of the copper ore deposit being developed are effectively verifying the technical methods and measures employed to date for eliminating the natural aerological hazards. Amounts of air supplied to mining areas, with lengthy transport routes, are becoming insufficient for miners’ temperature safety, whereas increasing the power of cooling air-conditioning stations for cooling the air undermines the economic legitimacy. However, along with the temperature hazard, a significant problem at the current depths is an increase in gaseous occurrences in the headings’ areas. The concentrations of natural harmful gases found, even with the values below the permissible concentrations, in the case of limited amounts of air and/or low airflow rates, may pose a considerable danger to the workers. The hazards referred to are currently the major factors determining the advance of headings, above all in mining sections, being the outcome of geological structure and depth of lying of a deposit. However, at the current depths of mining minerals from deposits, room-and-pillar mining systems employed also have a decisive impact on the increase in natural aerological hazards."

Jan 1, 2019

By Sung-Hyun Park

Core sediment samples collected from the KODOS area of the Clarion-Clipperton Fracture Zone in the NE Equatorial Pacific were analyzed for chemical and mineralogical compositions to investigate the depth- and time-related variation of paleoenvironmental and paleoceanographic conditions during their deposition. These core sediments are divided into three layers from top to bottom by its color; 1) brown layer (Unit I), 2) pale brown layer (Unit II), and 3) black brown layer (Unit III). Geochronology of 10Be indicated the depositional age of Quaternary for Units I and II and of late Pliocene for Unit III with a potential short hiatus between them. Analyses of interelemental correlation identified three major groups of elemental groups that show moderate-to-strong correlations: 1) Al, Ti, K, and Fe representing for terrestrial alumino-silicate fraction of sediments, 2) Ca, P, REEs, Cu, and Zn for biogenic apatite, and 3) Mn, Ni, and Co for hydrogenous Mn-oxide. With an exception, Fe content was very high and showed fair correlations with Mn, Ni, and Co in Unit III. Unit III shows high smectite but low quartz and illite contents compared to the overlying two units, indicative of reduced supply of terrestrial materials. In a meanwhile, major elements (Fe2O3, CaO, P2O5), minor elements (Cu, Zn) and REEs are highly enriched in Unit III compared to the upper two units. All these elements other than Fe reflect the fraction of biogenic apatite, which indicates higher fraction of biogenic components in Unit III. This is also supported by higher amount of smectite formed by the consumption of siliceous biogenic components. The reduced supply of terrestrial material and/or increased productivity of surface water at the time of Unit III deposition are attributed to Pliocene warming preceding Northern-pole glaciation during Quaternary. Unit III also includes clinoptilolite and unidentified 8Å mineral, likely amphibole, that are absent in Units I and II, suggestive of the possibility of different source region and/or materials during Pliocene. Higher contents of Mn and Fe in Unit III are likely due to the high fraction of Mn-oxide that was formed by diagenetic process after deposition.

Jan 1, 2003

In the United States water pollution resulting from mining activities has long been recognized as a major environmental problem Mine drainage pollution results from many types of mining activities and includes both physical (i e , sedimentation) and chemical (i e , acidification, metal contamination, etc ) pollutants Active and abandoned surface and underground mines, mineral processing plants, mine and processing plant waste disposal areas, haulage roads, and tailing ponds are typical sources of mine related water pollution (130) One of the most serious pollution problems arising from mining activities is acid mine drainage resulting from the chemical reaction of sulfide minerals (commonly iron sulfides) and air in the presence of water Acid mine drainage is commonly associated with coal and hard rock mining areas in the United States In general the more serious and extensive acid mine drainage problems exist in the more humid coal regions east of the Mississippi River (11) In 1964 the U S Department of the Interior, Fish and Wildlife Service, reported that acid mine drainage adversely affected fish and wildlife habitat in 9,477 kilometers (5,890 miles) of streams and 6,062 hectares (14,967 acres) of impoundments in 20 states in the United States (64) Of the total affected waters, coal mining operations accounted for 97 percent of the acid mine drainage pollution reported for streams and 93 percent of that reported for impoundments In 1970 more than 19,308 kilometers (12,000 miles) of streams in the United States were reportedly significantly degraded by mining related pollution (130) Of the total affected kilometers, 16,920 kilometers (10,516 miles) or approximately 88 percent were located in the Appalachian coal region (Pennsylvania, West Virginia, Ohio, eastern Kentucky, Tennessee, Maryland, and Alabama) In addition, more than 965 kilometers (600 miles) of streams reportedly were degraded by coal mining in states in the Illinois, Western Interior, and Rocky Mountain coal regions The remaining portion of the stream pollution resulted from the mining of (1) copper (california, Montana, Nevada, New Hampshire, Tennessee, Virginia, and Wyoming), (2) lead and zinc (Colorado, Idaho, Kansas, Missouri, Montana, Oklahoma, and Tennessee), (3) uranium (Rocky Mountain States), (4) iron (Lake Superior iron region), (5) sand and gravel (all states), (6) phosphate (Florida and other states), (7) gold (Alaska), (8) bauxite and barite (Arkansas), and (9) molybdenum, gold, and other metals (Colorado) Abandoned mines and abandoned mine waste disposal areas contribute a large portion of the total pollution resulting from mining activities Numerous abandoned underground mines are located throughout the United States and many are discharging mine drainage pollutants In 1966 the U S Bureau of Mines estimated that more than 88,000 inactive and abandoned underground mines were in existance (126) A listing of these mines by state is presented in Table 1 0-1 More recent estimates indicate that this list is incomplete In Colorado alone there is

Jan 1, 1975

By N. A. Abdel-Khalek

An experimental study was carried out to compare the results of laboratory column flotation versus conventional flotation for the cleaning of fine coals of different rank and their oxidized samples as well as discrete size fractions. Surface oxidation caused a significant reduction in the flotation yields achieved with both methods. However, the column flotation produced concentrates? of lower ash content. The recovery -size curve achieved with column was similar in shape to that obtained with conventional cell, with superior results in the region of fine fractions. The influence of some column operating parameters was also discussed.

Jan 1, 1990

By V. T. BERNER

THIS apparatus was designed primarily to meet the demand for a quick, efficient stopping to seal off the burning area temporarily during a mine fire, but it can be used in any circumstance where an immediate brattice is required for ventilation control. In using the old style brattice, mine-rescue workers have found it difficult, in smoke-laden drifts and stopes, to erect an effective stopping with wooden frame and canvas. Stulls must first be cut to the proper length, the canvas tacked in place, and the numerous irregularities of the walls and back must be caulked. This operation requires the employment of axes, saws, and hammers, which cannot easily and safely be handled in dense smoke. The fire fighters have often been forced to abandon their brattice, unfinished, because of the rapid approach of the fire, or because of the exhausted sup- ply of oxygen in their breathing apparatus. It is neces-

Jan 1, 1930

By X. L. Song, G. W. Zhang, F. Y. He, X. Xiao, L. L. Huang

This paper presents the design of a model and process simulation of a vertical mill based on a population balance model. The simulator, Simulink, which is a systematic modeling tool within MATLAB, was used for the simulation. The model will simulate the real time variation trend of each size fraction in the feed material to the vertical mill, as well as, the size distribution of the batch grinding products. Breakage distribution and selection functions are calculated based on batch grinding laboratory experiments using Back-calculation method. The simulated size distributions correspond with those in the actual mill operation having a relative error of less than 0.50%. This work lays the foundation for future research on modelling and simulation of a closed circuit grinding operation consisting of a vertical mill with hydrocyclone classifier.

Jan 1, 2016

By R. R. Dorfler

The existing regrind circuit at the Climax Operations uses sodium cyanide and Nokes reagent to reject pyrite, copper, and lead minerals. Laboratory flotation studies were performed using feed to flotation following first-stage regrinding. The effects of conditioning time, pH, and the concentration of depressants such as Nokes reagent and sodium cyanide on the rejection of pyrite, lead, and copper minerals were investigated. The metallurgical results indicate that, in the presence of depressants, the rejection of copper is strongly dependent on the pH. Preliminary mill testing confirmed the finding. The rejection of impurities is also dependent on conditioning time. The recovery of molybdenite is independent of the variables investigated.

Jan 1, 1981

By Peter Halbach

Cobalt-rich ferromanganese crusts are one type of the two oxidic metallic mineral resources in the deep ocean that incorporate metals supplied and transported from both land (aerosols, continental run-off) and sea sources (oxygen-minimum zone, hydrothermal alteration of the oceanic crust). The substances directly precipitate from cold seawater under more or less oxic conditions and form thin layers (2 up to 25 cm thick) on hard substrate rocks like volcanic hyaloclastites, weathered basaltic rocks and/or carbonate-fluorapatite; in the crusts many metals therefore exist in the highest state of oxidation. Deposits of the Co-rich ferromanganese crusts are found throughout the global oceans on the flanks, terraces and summits of seamounts and submerged volcanic mountain ranges and platforms, where the ocean currents have kept the seafloor more or less free of sediment for millions of years. The process of hydrogenetic precipitation is basically an inorganic colloidal-chemical and surface-chemical mechanism. Elements in seawater may occur as dissolved hydrated ions or as inorganic as well as organic complexes which in general have either a positive or a negative surface charge depending on the pH of the respective aqueous environment. Those complexes may form hydrated colloids that interact with each other and with other dissolved hydrous metal ions. Hydrated cations such as Co, Ni, Zn, Sn are, for example, attracted by the negatively charged surfaces of colloidal hydrous Mn-oxide particles, whereas hydrated anions (e.g. oxyanions) and elements forming larger complexes with low-charge densities (e.g. U, As, Th, Hf, REE) are attracted by the slightly positively charged hydrous Fe oxihydroxide particles.

Jan 1, 2008

By Pratama Mochamad Rizki, Andika Satya

High-risk area in open-pit mining should always be monitored by the operational supervisor because of its nature. One of this type is the soft soil dump area. Due to the unstable bearing capacity of the soil, it’s highly possible for us to find cracks in the area. This paper aims to build computer vision which able to detect truck’s distance from safe limit allowed during dumping activity. The system will warn the truck’s driver if the truck has crossed that predetermined safe limit.

Jun 25, 2023

By Jack Wright

The analysis of water produced with crude petroleum has interested oil producers since inception of the industry. Records of the first analysis of mineralized water produced from an oil-productive formation are obscure, and references to the first use of brine analyses to assist in solving problems of petroleum production are not available in the technical literature. However, many early reports of the Federal Bureau of Mines5-8 and Federal Geological Survey,9-11/ as well as articles in engineer and geological journals12-14/ placed special emphasis on the importance, interpretation, and application of water analyses. One of the earliest applications of water analyses, and still a major one today, is for identification of intrusive waters in oil wells. This may be done by comparing the chemical constituents of a sample of water indigenous to the oil-productive formation with those of samples from upper, water-bearing formations within the same general area. Some earlier investigators recognized the need for Analyzing samples of all waters encountered in drilling operations. Ambrose15/ stated, in part, "In wells being drilled, the engineer should grasp every opportunity to get a true sample of water from each sand. . .," and, "The waters of each oil field are chemically different from those of another field." The validity of the latter observation and the importance of the former one have been borne out by comparing the results of analyses of many samples and noting the differences in relative concentrations of like constituents of waters from the a geological formation in different localities or oil pools.

Jan 1, 1957

By Marcel Vanpee

Eight extinguishing powders KCI, were tested on five types of diffusion flames. The effect of flame temperature on the inhibition efficiency was investigated by varying the oxygen index of the flame supporting atmosphere. Inn addition a spectrographic investigation of powder flame dissociation products was carried out on the methane/air/ABC (NH4H2PO4) flame. Dissociation products for this flame included P0, PH, NH, and Na. It is concluded that the main factor to be considered in the efficiency of tie powder is the flame temperature Purple K (KHC03) was typically inefficient in low temperature flames and very efficient in high temperature flames. On the other hand, ABC (NH4H2PO4) was found to lose its efficiency at high temperature but to be quite efficient in the low temperature flames. The effect of temperature is offered as an explanation of the poor efficiency of Purple K (KHC03), against coal dust explosions as contrasted to the high efficiency of phosphate salts against coal dust explosions.

Jan 1, 1982

By C. Melvin Lepper

The Bureau of Mines has developed an improved earth resistivity field system which employs a novel technique for obtaining null measurements. The instrument is designed to operate reliably in high-noise environments such as those found in the vicinity of operating mines. The system consists of a low-frequency transmitter, a sensitive receiver and an external battery pack, each in its own case to provide protection from the elements. The receiver and transmitter units have self-contained recharge-able batteries to supply power to the circuitry and separate built-in battery chargers that operate on standard 115 Vac power. The system is portable and simple to operate. Measurement accuracy, reliability, and dynamic range are superior to most commercially available equipment even though less time and effort is required to make null readings. Unlike some commercial systems, long integration times are not required to enhance signal-to-noise ratio in areas of high background noise.

Jan 1, 1974

By Clyde E. Williams

[As a results of work conducted during the past three years, the Northwest Experiment Station of the Bureau of Mines, in cooperation with the University of Washington at Seattle, Washington, has developed a process for the production of sponge iron. Commercial operation of this process in a 3 to 4-ton scale has been so satisfactory that its use on a large scale (20 to 100 tons per day) can be safely considered. Description of Process. The process consists in passing a mixture of iron ore and coal through a rotating kiln heated at one end to a temperature sufficient to convert iron oxide to metallic iron, discharging, cooling, and separating the sponge iron from the residual coke and silicious material on a magnetic separator. Both the coal and the ore should be crushed to peso as 6-meth scream, tans producing particles finer then 1/12 of an inch. Seventy-five parts of coal or other carbonaceous material arc charged with every 100 parts of ore), This large amount of coal is required in order to supply sufficient carbon to maintain a strongly reducing atmosphere in the charge, but may be reduced to about 65 parts per 100 parts of ore by recovering and using tae carbon that remains in the discharge product. Large-scale operation and refinements in furnace design should lower this ratio to perhaps 56 or 60 parts of coal to 100 parts of ore.]

Jan 1, 1924