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By A. Lindo, M. Held

The formation of NOx fumes is an undesired occurrence and is dependent on a variety of variables. Methods for detection of such fumes with blast analysis tools are available using color schemes for grading, but no quantification tools to measure concentration and cloud totals exist today. In cooperation with DIRS (Digital Imaging and Remote Sensing Laboratory) at RIT in Rochester, NY, Austin Powder has been looking for methods and techniques to identify and quantify total amounts of NOx by capturing cloud activity via a video feed from a drone in combination with measuring NOx and subsequent cloud modeling (i.e., plume segmentation). To accurately measure fume events, Austin Powder and the RIT team have been collaborating in performing small scale blasts at an Austin test facility and then transferring knowledge learned to full scale blasts at customer sites. The collected data will allow to identify any relationships between the total amount of explosives used and the quantity of NOx produced. The analysis of the total amounts of NOx and identification of blast areas those fumes originate from will help to better understand key factors that contribute to their occurrence as well as to quantify the severity of such events. By quantifying the magnitude and concentration of fumes generated by non-ideal detonations, the blasting technique can be optimized to minimize unwanted environmental effects and improve public perception of blasting as a necessary component of societal progress

Jan 1, 2024

By D. L. Forrester

This paper, describing the milling practice of the Old Dominion Co., is one of a series being prepared by the: United Staten Bureau of Mines. ACKNOWLEDGMENT In the preparation f this paper, acknowledgment is made of the valuable service rendered by R. S. Allen, metallurgist of the Old Dominion Co. T. G. Chapman, one f the consulting engineers of the Bureau of Mines, assisted in arranging the paper for publication.

Jan 1, 1931

By L. Frost

The establishment of a retreat system of longwall mining in this submarine coal field has been under study for many years and, although in special cases there have been limited local applications of this method of mining, there has been no attempt until quite recently to establish a uniform system of longwall retreating' in this area (see Figure 1) Where retreat walls were established, it was strictly as a result of physical, rather than economic conditions. In some of the operations- of the Corporation, where the coal was liable to spontaneous combustion- or the area subject to bumps as in No. 2 Mine of the Cumberland Railway and Coal Company in Springhills the recovery of the coal on a retreat system was more or less a necessity.

Jan 1, 1964

By J. F. McMahon

Introduction The greater portion of the information presented in this paper was obtained in the course of an investigation on clay gathering and its cost in the provinces of Quebec and Ontario (1). For assistance in the preparation of the paper, the writer wishes to record his thanks to Mr. Howells Fréchette, Chief of the Ceramics and Road Materials Division of the Mines Branch. Clays are mineral substances consisting essentially of hydrous aluminium silicate which become plastic when wet, fairly hard when dry, and stony masses when burned to a sufficiently high temperature and re-cooled. Shales are clays which have been indurated by the processes of nature. Millions of tons of clays and shales are won yearly for the production of brick, tile, sewer pipe, drain tile, roofing tile, fire-brick, china-ware, wall and floor tile, cement, and a host of other products. There are certain types of clay which, due to their particular qualities and limited distribution, are mined entirely or in part for sale to manufacturers, and are even exported from one country to another, as for example china-clays or kaolins, utilized in the manufacture of white-wares and in the paper industry, due to their consistent whiteness; ball-clays, utilized in the white-ware industry, due to their bonding power and whiteness; slip-clays, used in the stone-ware industry because of their glazing properties, and in the grinding-wheel industry for their burned bonding properties; and suspension-clays, such as are used in the enamelling industry. However, the great bulk of clays and shales won are used in the production of heavy clay products, and the manufacturer of these generally owns and operates his own deposit of raw material.

Jan 1, 1933

By James M. Barker

Industrial minerals are critical to most aspects of modern society. They are pervasive in both industry and in everyone's lives (McVey, 1989; Barsotti, 1993). They are also the dominant class of minerals produced in the United States but this fact is little known outside the industry. For example, in 1993 (U.S. Bureau of Mines, 1995, table 1) industrial mineral dollar value was double that of metals ($20.86 billion vs. $10.88 billion) and employment levels were nearly so (74,000 vs. 40,000). A further difference is that transportation tends to dominate production costs (FOB end user) whereas they are much less significant in other mining ventures or other industries. Finally, metal mines are more concentrated west of the Mississippi; industrial mineral operations are more prevalent to the east (U.S. Bureau of Mines, 1995, p. 16-17). The significance of transport cost is discussed in Part 2, which is essentially Barker and Austin, 1995. Part 1 will update and expand portions of Barker and Austin (1995) and provide a more detailed discussion of import/export relationships using a China/United States reference point because of China's dramatic influence on some industrial mineral markets since the mid-1980s (barite, etc.).

Jan 1, 1996

A novel, low-pressure adaptation of Praxair?s coherent jet technology utilizing CoJet lances was developed for application at Inco&apos;s Copper Cliff Smelter where oxygen is available in large tonnage quantities but only at relatively low supply pressures (< 193 kPa header pressure). The project objectives were to evaluate the effect of coherent jet technology on controlling oxygen lance accretion (?horn?) formation and to increase oxygen efficiency in the Inco Oxygen Top-Blowing Nitrogen Bottom Stirring (TBBS) MK Reactor used for converting nickel- contaminated chalcocite to semi-blister copper. This paper describes the development and subsequent implementation and testing of two CoJet lances in this application.

Jan 1, 2005

By Rclssell Gibson, F. S. Turneaure

The tin deposit of Monserrat; Bolivia, consists of one major vein 1600 m in length. The ore is unusual because of the notable quantity of teallite, even though cassiterite is the principal tin mineral. The deposit, formed at shallow depth under a wide range in temperature, may be classed as xenothermal. Polished sections reveal a complex history of replacement, with low-temperature minerals deposited before high-temperature minerals.

Jan 1, 1950

By R. Hejazi, Saghaeian. M., H. Abedini

Continuous vacuum belt filters mainly carry out an important duty in the solid-liquid separation processes such as iron ore concentrate dewatering. However as the particles become finer, the resistance to filtration and dewatering would increase and as the result cake moisture content tends to increase. So in recent decades, using additives in order to improve the filtration performance has been considered by many researchers. In the present study, the effect of several surfactants on the filtration rate and cake moisture content of Chadormalu iron ore concentrate (80% =40 micron) was investigated using a laboratory scale vacuum filter. The results of several tests indicated that a non-ionic surfactant (Lauryl Alcohol Ethoxylated, LAE) has the best performance on reducing the moisture content of the cake and reducing the cake formation time. The optimum dose of LAE was found to be 300 g/ton which reduced the concentrate cake moisture content from 13.76 to 11.28% (wet weight base). Some industrial filtration tests were performed in Chadormalu iron ore concentrate plant to prove the effectiveness of this surfactant. The surfactant is mixed with water and added to the concentrate slurry before distributing on the vacuum belt filter. The industrial and experimental results were almost similar, so that adding about 300 g/ton of LAE would reduce the final cake moisture content from 12.87 to 10.76%.

Jan 1, 2014

By Xiaoming Wang

This paper describes a new magnetic separator integrating dynamic permanent magnetic force, gravity and flow dynamics to enhance the quality of the iron concentration. This equipment can increase the grade of concentrate by controlling the formation of magnetic agglomerations to reject most gangue. Test results indicates that the compound force field separator can be applied in improving the quality of iron concentrate and has a wide range of potential market applications. Keywords: magnetic separator, compound force field, rotating magnetic system, magnetite concentration

Sep 1, 2012

By T. Muldoon

Literature review and extensive field survey of line and check curtain materials and practices showed: ? Miners, in general, know how to set tight curtains, and do so when needed. ? The tradeoff is economic; tight ventilation is labor-intensive. Line and check curtain techniques found are catalogued and evaluated. A fieldworthy 10 ft extensible brattice to maintain a 10 ft setback was found in use in two mines on continuous miner faces. This technique was evaluated in the laboratory for leakage and methane control at the face. Significant results include: 1) Air leakage through a gap in the extensible curtain depends upon the ratio of the cross-sectional areas between entry and return as well as gap area; 2) Gap shape has no significant effect on methane concentrations at the face -increasing gap area diminishes ventilation effectivness; and 3) Substantial reductions of CH4 concentrations at the face were accomplished by brattice extensions with gaps of up to 5 ft2 in area. An "inby hook," inserted in the roof automatically to make possible the deployment of a longer (20 ft) brattice extension in the context of a remotely controlled miner, was tested in various roof types. Insertion of this design succeeded only in coal.

Jan 1, 1982

By Gerald A. Zicg

The Sheep Creek project area lies between 15 and 20 miles north of White Sulphur Springs in west central Montana, on the southern flanks of the Little Belt Mountains. The Sheep Creek project is a joint venture in which Cominco American Resources, Inc., has a 50% operating interest and BHP-Utah International, Inc., has a 50% participatory interest. The property consists of over 40,000 acres of leased fee land and lode claims. Modern exploration of the Sheep Creek area began in 1973 and 1974, when Homestake Mining Co. examined the extensive Sheep Creek gossans with soil sampling, trenching, and drilling. Cominco American Inc. began exploration in the area in 1976. Between 1978 and 1985, Anaconda Copper Co., Exxon Minerals Co., and Freeport also conducted exploration programs in the area. In 1985, Cominco completed consolidation of the district, gained BHP-Utah International, Inc., as a joint venture partner, and the joint venture drilled the first significant copper mineralization on the property. Of six bodies of copper mineralization so far located, the best defined are an upper copper zone, which includes a probable resource of 4.5 million metric tonnes grading 2.5% Cu and 0.1 % Co, and a lower copper zone which includes a possible resource of 4.5 million metric tonnes grading 4% Cu. Exploration drilling of the property is in progress.

Jan 1, 1991

By Frank E. Chase, John Rusnak, David Newman

During the past quarter century, coal mine geologists have evolved from providing a qualitative description of drill core and coal reserves into quantitative geotechnical specialists who bridge the gap between geology and engineering. In the late 1970’s and early 1980’s, hazard prediction mapping was in its infancy. At best, hazard maps identified rudimentary structures and conditions such as stream valley locations, sandstone/shale transition zones, and lineaments. A “technical disconnect” had existed between geologists and mining engineers as each profession operated largely independent of each other. Engineers did not readily integrate geology and geologic conditions, with the exception of coal thickness, into mine planning. Geologists were relied upon for reserve estimates and did not participate in mine planning or design. The employment and market slump of the 1980’s and 1990’s combined with mining more challenging reserves mandated that this gap be bridged and forced geologists to learn to speak more “numerically” to engineers so they could be understood. The purpose of this paper is to describe the procedures and thought processes used by coal mine geologists when determining various mineability and reserve extraction feasibility issues. The paper will also address underground geologic hazard mapping and prediction techniques. To achieve these objectives, the opinions and experiences of leading coal mine geologists, geotechnical and strata control specialists across the United States were solicited.

By S. T. L. Harrison, A. Kotsiopoulos, M. D. Maluleke, E. Govender-Opitz

In the extraction of base metals from printed circuit boards (PCBs) using bioleaching, the accumulation of metal ion stress in solution has been shown to inhibit the microbial regeneration of ferric iron. This poses a challenge for the development of this technology for e-waste treatment. The paper explores the application of a microbial immobilisation system in a two-stage bioleaching system consisting of a chemical leaching reactor in series with a microbial ferric iron regenerating reactor to mitigate microbial inhibition and to enhance base metal extraction. A mixed microbial culture dominated by L. ferriphilum, L. ferrooxidans and At. Caldus was maintained over a period of two months in the presence of polyurethane foam which acted as the biomass support particle. Microbial metabolic activity of immobilised cells and their tolerance to inhibitory Cu ions was investigated. Results showed that immobilised microbial cells maintained higher ferrous iron oxidation activity compared to planktonic cells in the presence of increasing Cu2+ concentrations up to 6 g/L. This presents an opportunity for microbial immobilised systems to be adopted in two-stage bioleaching system. Keywords: Bioleaching, microbial immobilisation systems, microbial inhibition and ferrous iron oxidation

Jan 1, 2020

By William G. Pariseau

A small displacement-small strain finite element technique utilizing the constant strain triangle and incremental constitutive equations for elastic-plastic media that are nonhardening and obey a Coulomb yield condition has been applied to the analysis of gravity flow initiation in a V-shaped hopper containing a powder under lunar environmental conditions. Three methods of loading were examined. Of the three, the method of computing the initial state of stress in a filled hopper prior to drawdown by adding material to the hopper layer-by-layer is superior (as expected). Results of the analysis of a typical hopper problem show that the initial state of stress, the elastic moduli, and the strength parameters have an important influence on material response subsequent to the opening of the hopper outlet.

Jan 1, 1971

By A. U. Miller

Since coal -mining records have been kept , reports of all mining States show that each year the lives of many workers have been sacrificed in the production of coal , and Illinois has contributed its share , Illinois reports for the 50 years 1882 to 1932 , inclusive , show that 6,673 men were killed -- 6,121 underground , 340 in the shaft , and 212 on the surface . Of the fatalities underground , 3,116 were caused by falls of roof or sides , 1,111 by haulage , 630 by explosives , 577 by gas explosions , 139 by electricity, and 548 by other causes ; 166 of the shaft fatalities were caused by falling down the shaft , 143 by the cage , and 31 by other causes ; 108 of the surface fatalities were caused by railroad cars , 46 by machinery , and 58 by other causes . Most of those engaged in mining are still of the opinion that it is an extremely hazardous occupation and that it is practically impossible to operate without accidents ; however , students of safety in mining now believe that with the proper attention to accident prevention mining may be conducted with little , if any , greater accident rate than that of other supposedly hazardous industries . There is no mystery connected with accidents in mining ; reports show that the majority are due to two main causes , falls of roof and sides and haulage . Mining companies in Illinois , as well as in other States , have proved in the past few years that the hazards of mining , like those of other industries , can be controlled to a large extent and the mines operated with few if any accidents , provided a great enough effort is made by employer and worker . Although the past accident rate of Illinois may compare favorably with that of other mining States it is higher than it should be ; the fact that 6,673 men (an average of 133.46 per year) were killed in and around the mines of the State between 1882- and 1932 indicates that accident prevention should receive more consideration in the future than in the past .

Nov 1, 1934

By M. K. McCarter

Surface mining applies to extraction of mineral resources from water and sediments of rivers, lakes, seas, and oceans; from solutions circulating through broken rock and soil; and from rock and soil excavated from the earth. Surface mining is responsible for the majority of mineral production in the United States and a substantial portion of the world?s total production. This section deals specifically with extraction methods which employ mechanical processes in a relatively dry environment to free minerals from the earth. The following section, Section 15, deals exclusively with aqueous methods. With recognition of the importance of reclamation in all activities which temporarily disturb the earth?s ecosystems, it is appropriate to classify mechanical extraction methods as either deferred reclamation or concurrent reclamation. Deferred reclamation is necessary when the shape and logistics of the excavation require that it remain open throughout the productive life of he project. Upon exhaustion of economic reserves, the opening is then reclaimed in a manner consistent with public safety, environmental acceptability, and land use policy. Methods employing deferred reclamation are commonly referred to as open pit or quarry mining. Metallic ores, industrial minerals, and coal are all extracted using open pit methods. Typical examples are provided in Chapter 14.1.

Jan 1, 2008

By John Postle, Maureen Jensen, Marcel Vallee, Bernie Haystead, Dan Hora, Graham Clow

The Committee's proposed standards establish definitions and guidelines for the reporting of Exploration Information, Mineral Resources and Mineral Reserves in Canada and are identified as the "CIM Standards" and referred to as such hereafter in this document. To provide additional clarification to Qualified Persons (QPs), guidelines have been included with the respective definitions. The CIM Standards are applicable to all minerals including industrial minerals, diamonds and other gemstones. Reserve definitions for bitumen, natural gas and oil are not included in these Standards. The CIM Standards are not intended to cover mineral inventory estimates that will be reported to government agencies.

Jan 1, 2001

To carry out its responsibilities the SECV needs to manage the visual environment effectively. Every land oriented decision effects what we see and the value in pursuing visual excellence is supported by informed opinion, widespread community interest and evidence of cost- effectiveness.By knowing how we perceive the landscape and then changing or conserving it we can assist in fostering a positive mental image of a countyside which is welcomed by the local and regional community.It is useful to examine key design elements and the value we place on visual impressions in relation to three significant SECV rehabilitation projects, at Loy Yang, Newport and Morwell Open Cut.

Jan 1, 1992

By G. E. McElroy

The purpose of tins paper is not to present new date on the pressure losses due to bends and chances of area in mine openings through which air flows, but rather to correlate existing data, determined mainly on small duct systems and expressed in a variety of ways, according to uniform methods that facilitate their use in pressure-loss computations. These are required in such, air-flow problems as determining the quantity that will flow through is mine openings under a certain pressure difference or, conversely, the pressure difference that will be required to maintain a certain rate of flow. Air flowing through h ducts, such as mine airways, encounters resistance to flow due to interference of the individual air streams with each other caused by the wall surfaces. The result is that part of the kinetic energy of the flowing stream is converted to heat; and constant renewal of the kinetic energy from the total energy of the flow is required to maintain it. This process manifests itself by a decrease of the total pressure (static pressure plus velocity pressure; of the air in the direction of flow; in order that flow pray occur, there must necessarily be a differences in total pressure between the two cads of the air-ay equivalent to the pressure losses occasioned by the flow, which automatically adjusts itself in magnitude to the pressure difference maintained.

Jan 1, 1932

By W. S. Landers

Analysis of the size consist of broken coal has been extended in recent years beyond the mere representation of the relative quantities of the various sizes present in a given lot of the material. Fundamental characteristics of the coal related to the process of breakage fix the distribution of sizes, and it has been found by Rosin and Rammler4/ that a relatively simple law-governs this property. Benhett5/ has described a graphical method of expressing the relationship, and by its use considerable simplification in the expression of size distribution is possible.

Jan 1, 1946