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By David M. Spatz

The way people interact, collaborate, learn and improve can have a profound impact on a company’s efficiency, performance, productivity and return on investment. This is the motive behind corporate efforts today to replace the traditional hierarchical structure with team-oriented organization. The increased importance of communication and collaboration during the past 20 years has been propelled by rapid advances in technology and increased availability of information. Companies must take advantage of the information that is required for competitive performance and for the continued production of quality products. So it is essential that outstanding communication, cooperation and collaboration take place among multidisciplinary specialists assigned to work together to solve common problems and achieve common goals. Companies are searching for ways to increase knowledge transfer and learning, particularly among people who work on related topics. This will improve efficiency and quality and reduce redundancy and costs.

Jan 1, 2000

Comparison of Grinding and Liberation Processes for Stalky Biomass Materials as a Prerequisite for Production of Energy Pellets with High Calorific Value Pelletising biomass, especially straw and stalky materials, requires a product specific size reduction and liberation. However, moisture content plays an important role in palletising and also affects the energetic properties of the biomass. The paper illustrates the characteristics of the mentioned type of biomass and specifies the necessities for production of energy pellets. Defined requirements for biomass energy pellets will be shown based on relevant standards. The work focuses on a comparative investigation of the straw fibres after grinding with hammer/impact mill and after the liberation of the straw fibres with twin-screw extruder (two different communition units). A traditional hammer mill as well as an hydrothermal process taking place in a twin-screw extruder were utilised. Results of the grinding and liberation of rye and wheat straw fibres are discussed based on a detailed particle characterisation (particle size and shape distribution). Besides high calorific value the main pellet quality parameters are mechanical stability, abrasion resistance and further combustion technical characteristics. The particle size distribution displayed optimum characteristics for the combustion processes to be carried out in a furnace. The durability of the pellets produced from straw fibres liberated with twin-screw extruder was comparatively better then that prepared with the straw fibres after grinding with impact mill. Particle size distribution, abrasion values and the strength characteristics showed a good correlation with each. The high presence of N and S would result in high NOx and SOx emissions, where as the high concentrations of Cl would corrode the furnace. These chemical properties of the straw would restrict its usage in small scale furnaces.

Sep 13, 2010

"Each and every flotation plant must produce daily/weekly/monthly production reports in which metal balances for payable and penalising elements are presented. Several factors including ore heterogeneity and harsh production environment affect the reproducibility of the reported data. Best practices of metal accounting thus prescribe that production reports be accompanied by measurement quality reports quantifying the reproducibility (a data quality metric often expressed as a relative standard deviation) of each data reported. Ignoring the irreproducibility of measurements may lead to the perception that random errors have been totally eliminated through statistical data reconciliation, which is wrong. This paper aims at explaining the full lifecycle management of reproducibility estimation from the outset at the measurement process to its reporting after having been through the statistical data reconciliation process. Indeed, the reproducibility of reported data can be obtained by performing a sensitivity analysis. Necessary conditions for obtaining a truly representative assessment of measurement reproducibility are stated. Typical levels of measurement reproducibility found in operating flotation plants are also reported. These numbers can be used as benchmarks for reproducibility levels that can be realistically expected.IntroductionEach and every flotation plant must produce daily/weekly/monthly production reports in which metal balances for payable and penalising elements are presented. Such production reports are the most expected output from a metal accounting system (MAS). The duly recurrence of this task combined with an insufficient level of automation has somehow contributed to the misleading perception that it is mainly a clerical work. However, as shown in Figure 1, a MAS encompasses way more than just a reporting system. Acknowledging that the content of production reports indubitably origin from raw measurements has important implications for how both the reports and MAS should be monitored."

Jan 1, 2016

Accurately estimating load distributions and ground responses around underground openings play a significant role in the safety of the operations in underground mines. Adequately designing pillars and other support measures relies highly on the accurate assessment of the loads that will be carried by them, as well as the load-bearing capacities of the supports. There are various methods that can be used to approximate mining-induced loads in stratified rock masses to be used in pillar design. The empirical methods are based on equations derived from large databases of various case studies. They are implemented in government-approved design tools and are widely used. There are also analytical and numerical techniques used for more detailed analysis of the induced loads. In this study, two different longwall mines with different panel width-to-depth ratios are analyzed using different methods. The empirical method used in the analysis is the square decay stress function that uses the abutment angle concept, implemented in pillar design software developed by the National Institute for Occupational Safety and Health (NIOSH). The first numerical method used in the analysis is a displacement-discontinuity (DD) variation of the boundaryelement method, LaModel, which utilizes the laminated overburden model (Heasley, 1998).

Jan 7, 2020

By Conochie D. S, Grave N. C

Disposable-tip emf cells at present used in liquid steel can be used to measure the state of oxidation of high-iron slags produced in non-ferrous smelting. This provides a new tool for the control and evaluation of pyrometallurgical operations.An investigation of oxygen potential variations throughout a typical nickel smelter using the flash smelting technique gave a valuable insight into the process. Correlations of oxygen potential with ferric to ferrous oxide ratio and nickel content in slag were in reasonable accord with equilibrium data in the literature indicating that the probes may be used both as a plant investigation tool and possibly as a means of obtaining thermodynamic data for slags.

Jan 1, 1979

By F. N. Kissell, C. M. McCulloch, Maurice Deul, J. R. Levine

The methane content of virgin bituminous coalbed can now be measured accurately in the field with exploration core samples from vertical boreholes. The gas content of the coal per unit weight can be used either to design a mine ventilation system or to determine if degasification of the coalbed will be necessary before mining, and to determine the gas resources in the coalbed. The equipment necessary to conduct the test costs less than $50. The gas content of the coal in place in the ground is determined by summing the gas lost from coring, gas measured during desorption, and the residual gas in the coal. Upon removal from the borehole, the core sample is placed in an airtight container and desorbed for several weeks until the desorption rate is below 0.05 cm3/g for 5 consecutive days. The gas lost from the core while it was being cored and the residual gas are estimated by a new graphical method. The amount of gas remaining depends upon whether the coal is friable or blocky. Friability appears to relate to the depth of the sample below the surface, fixed carbon percentage, Hardgrove grindability index, and proximity to tectonic disturbance. Friable coals emit nearly 96 pct of the total gas during desorption whereas a blocky coal emits only 60 pct of its total gas. Coalbeds that are ill defined as to their blocky or friable nature must be tested in the laboratory for unambiguous analysis.

Jan 1, 1975

By Fred D. Fox

Introduction Abandoned mill tailings deposits can be found throughout the northern Black Hills of South Dakota, indicative of mining activities that originated during the great gold rush days of 1875. The Refuse Act of 1899 attempted to regulate the deposit of debris from mines and stamp works. But, in most cases, huge volumes of mine and milling wastes were disposed of in ways no longer considered environmentally acceptable. Restoration of gold mill tailings deposits is a relatively new practice to the Black Hills area. This discussion will present an overview of the environmental setting, environmental problems associated with past tailings disposal practices, practices being implemented to solve these problems, and prospects related to present the future tailings disposal practices. Environmental Setting An understanding of climatic characteristics, geology, surface and ground water hydrology conditions, and the physical and chemical characteristics of selected mill tailings deposits will aid in understanding environmental problems associated with tailings disposal and restoration. Climate The Black Hills region is in the middle latitudes, which have a

Jan 11, 1984

By I Thin, L Morizzi, C Seymour, G Mungur

Olympic Dam has been investigating mine design options for the South Mine Area (SMA), which will continue using the existing sublevel open stoping (SLOS) method. The SMA is an undeveloped mining area, located south of the existing underground mining areas currently in production at Olympic Dam. The SMA study reached the stage where geotechnical inputs were required for stope design, infrastructure location and ground support forecasts. A large database of geotechnical data was collected to inform open pit designs for the ODX (Olympic Dam expansion) project (resulting from 659 drill holes). This geotechnical data has since been reprocessed to align with design inputs required for the SLOS mining method. The result has been the construction of a preliminary three-dimensional mining rock mass model (MRMM) that has been incorporated into preliminary stope mine design and infrastructure layout assessments, which have taken into account the predicted prevailing ground conditions.As with any model, it is necessary to improve the confidence in its predictability; therefore the model must be calibrated. The preliminary SMA MRMM was no exception. First pass calibration was possible with results from underground geotechnical window mapping from exposed rock mass conditions in the lateral development and surface geotechnical holes for ventilation shafts.The SMA project continues to advance and has started a program of resource drilling. Selected holes have been identified that target data limited areas. This will ensure that the data gaps are infilled in order to maintain the required data density required to improve the model confidence. In addition, further underground window mapping in the SMA will provide ‘mine scale drill hole’ data that can be used to either update the MRMM or as part of planned future calibration. Stope performance data from stopes will provide further valuable data for calibration purposes.The proposed paper will present the process and findings that have been followed in order to establish a well calibrated geotechnical model that can be used with an acceptable level of confidence in the ongoing refinements of the mine design and planning process for the SMA.CITATION:Thin, I, Morizzi, L, Mungur, G and Seymour, C, 2016. Building and calibration of a geotechnical model for sublevel open stope design at Olympic Dam, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 523–532 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By F. D. Ayhan

The aim of this study was to investigate the effects of various water mediums on desulfurization and deashing of a coal sample using flotation. For this purpose, experimental studies were conducted on a coal sample containing high ash and sulfur contents. The effects of pH, solid concentration, collector amount and frother amount on the flotation were investigated separately in Mediterranean Sea water, Çermik thermal spring water, snow water and tap water. Flotation results indicated that, when comparing the various water mediums, the following order for the ash content was obtained: snow water < Çermik thermal spring water < tap water < the Mediterranean Sea water. For the reduction of total sulfur, the following order was obtained: snow water > Çermik thermal spring water > Mediterranean Sea water > tap water. When snow water was used as a flotation medium, it was found that a concentrate containing 3.01% total sulfur and 27.64% ash with a total sulfur reduction of 57.06% was obtained from a feed containing 7.01% total sulfur and 41.17% ash.

Jan 1, 2009

By George Straghan, Ralph Thomas

OIL production in Kentucky in 1941 was 5,191,024 bbl., one barrel less than in the preceding year. The total completions for the state numbered 714, of which 256 were gas Manuscript received at the office of the Institute Feb. 26. 1942. * Geologist, .Kentucky Weal Virginia Gas Co., Ashland, Ky. † Geoloneist. Inland Gas Co.. Ashland. Kv. producers, 220 oil wells, and 227 dry holes. The total number was 95 more than in 1940. No new important oil or gas pools were discovered. The number of dry tests was large, although many of the dry holes could be considered wildcat tests. In western Kentucky, 365 wells were drilled, of which 145 were oil producers,

Jan 1, 1942

By Ralph Thomas, George Straghan

OIL production in Kentucky in 1941 was 5,191,024 bbl., one barrel less than in the preceding year. The total completions for the state numbered 714, of which 256 were gas Manuscript received at the office of the Institute Feb. 26. 1942. * Geologist, .Kentucky Weal Virginia Gas Co., Ashland, Ky. † Geoloneist. Inland Gas Co.. Ashland. Kv. producers, 220 oil wells, and 227 dry holes. The total number was 95 more than in 1940. No new important oil or gas pools were discovered. The number of dry tests was large, although many of the dry holes could be considered wildcat tests. In western Kentucky, 365 wells were drilled, of which 145 were oil producers,

Jan 1, 1942

By Charles Bohdanowicz

As in preceding years, the most intensive drilling activity during 1934 took place in the old fields of the western part of the Polish Carpathian petroleum province (district of Jaslo). The number of wells completed to the end of 1934, expressed in percentages, is as follows: Jaslo district, 57 per cent; oil fields outside Boryslaw-Tustanowice-Mraznica, 27; Stanislawow district 8 and Boryslaw fields only 7 per cent. The number of meters drilled (Table 2), expressed in percentages, for the same fields are as follows: Jaslo district, 51 per cent; oil fields outside Boryslaw-Tustanowice-Mraznica, 26; Stanislawow district, 12, and Boryslaw oil fields, 11 per cent. This comparison shows that most of the new

Jan 1, 1935

CLASSIFICATIONS: 1, Nonferrous metals. 2, Iron and Steel. 3, Petroleum and Gas. 4, Coal. 5, Industrial minerals. A, Geology, exploration. B, Mining and production engineering. C, Preparation and milling. D, Physical metallurgy. E, Administration and economics. F, Chemical metallurgy. G, General. ARIZONA HASTINGS. EARL F., P. 0. Box 10 Chloride 1-A,B,C, Denver Univ., Texas Call. Mines. Asst. chief metallurgist, Old Dominion Copper Co., &apos;26-&apos;29; mine examination and mill construction in Colo.. Ariz.. and New Mexico; mill supt., Arizona Molybdenum Corp.. 34; at present gen. mgr., Pioneer Gold Mng. Co. Specialty: mine examinations and flow sheets of gold and rare metal plants. Examinations limited in Mohave County, A.riz., for present.

Jan 1, 1936

By R. J. Snoby, M. A. Short, A. Jungmann

In processing coal, the low concentrate value requires high capacity production and sharp classification/separation techniques to reduce specific production costs. The allflux separator meets these criteria with a unique two-stage design. Through a combination of rising current and fluidized bed technologies, the allflux has extended the state of the art by expanding the particle size range that can be efficiently processed. Using concepts that have proven successful in processing concrete sands, small-scale industrial testing with coal feed stocks looks very promising. Attractive applications for the allflux are projected in fine coal recovery from old settling ponds or as a retrofit in existing fines circuits.

Jan 1, 2001

By J. B. Gayle

The merits of the various methods for dry-quenching coke have been the subject of numerous publications and almost equally numerous controversies for the past 40 years.5/ Most investigators have concluded that dry quenching is advantageous. Some have based their arguments on the improved physical properties of the resultant cokes. Others have claimed little or no improvement and have based their arguments on the economies acquired from the recovery and utilization of sensible heat. The extent to which the method of quenching influences the properties of the resultant cokes is of importance in connection with the operation of both commercial and experimental ovens. On the other hand, the recovery and utilization of sensible heat are economic problems related solely to commercial oven operation and- depend on the method of dry quenching used and the demand for a low intensity energy source. The scope of the present Bureau of Mines investigation has been limited to a comparative study of the properties of wet- and dry-quenched cokes produced from six coals and blends carbonized at flue temperatures of 2, 000° and 2,400° F. in the Tuscaloosa oven.

Jan 1, 1959

By George H. Holmes

The water situation in Nevada mineral and related industries is described in this report. It contains information on the sources and adequacy of supply to current operators, requirements and uses, quality and costs, geography, hydrography, precipitation and evaporation characteristics, and Nevada water laws. Also, information is given on the water requirements of one public utility powerplant, and the source and consumption of water in four major cities. Water distribution at 24 operations is shown on schematic waterflow diagrams. The mineral industries of Nevada in 1962 used 8.6 billion gallons of new&apos; water and reused 3.8 billion gallons for a total usage of 12.4 billion gallons. The copper industry was the major water user. The 1962 value of all mineral production in Nevada was $85.5 million. The large amount of water required to maintain thin high production is obtained principally from ground-water sources in alluvial valleys and the permeable rock formations of some mountain ranges. Some water is also obtained from perennial streams and springs. Sources of water utilized by existing industry ire near most mineral industry operations; however, seven companies are forced to pipe water distances ranging from 2 to 8 miles. Although water supplies of presently operating companies are adequate at most operations, several companies resort to large-scale reuse of water as a matter of conservation and economics. Acquisition of water by new operators is possible but takes considerable negotiation. Water rights, surface and underground, are controlled by the State. The quality of the water is satisfactory for most purposes. Analyses of 19 samples, listed in the appendix, show the range in water quality at various plants throughout the State. Costs of delivering new water to current operations range from 2 to 26 cents per 1,000 gallons with an average of 10 cents per 1,000 gallons for power and maintenance. No firm costs for recirculating water were available; estimated costs range from 1.5 to 2.5 cents per 1,000 gallons. The mineral-product value of the entire Nevada mineral industry in 1962 was equivalent to $10 per 1,000 gallons of new water and $26 per 1,000 gallons consumed. Projection of the 1962 water requirements of the Nevada mineral industry indicates that the demand For new water will increase from 8.6 billion gallons in 1962 to 11.9 billion gallons in 1980, a 43-percent increase. Water requirements in the year 2000 are estimated as 14.8 billion gallons, an increase over 1962 water demand of 78-percent.

Jan 1, 1966

By Peter B. Lilly

Thank you, Syd, for the kind introduction and for inviting me to give the Keynote Address at this very prestigious gathering of some of the finest intellect and talent in the domestic and international coal industry. CONSOL Energy has been a part of this conference for its entire 24-year existence. We have presented 27 papers over that time. CONSOL employees have also been members of the planning committee for the conference, and we have been pleased to support the event both financially and with many participants. So I am honored to be here with all of you this morning, especially during such a positive period for coal. You can just feel the enthusiasm in this room for our industry, and for this conference. I can tell you, there?s also a lot of enthusiasm and excitement in CONSOL Energy?s boardroom. And our enthusiasm is mirrored on Wall Street. But there remains an ironic twist to all of this attention. Even when times are good, the coal industry seems to go largely unnoticed by the mainstream. Outside of West Virginia and other coal-producing regions, the industry still seems to lack influence and support, at least here in America. As an example, last month, an ABC News crew visited our Blacksville 2 Mine, near here, to do a feature story on increased employment in the coal industry.

Jan 1, 2006

By M. Nete

Qualitative analysis of three mineral samples from northern Mozambique was accomplished by X-ray diffraction (XRD), microscopy, scintillation, and magnetic determination. Chemical characterization was accomplished using ICP-OES and pressed powder XRF after dissolution using microwave-assisted digestion and flux fusion. The samples consisted of a mixture of minerals with tantalite as the major component, with minor amounts of microlite, quartz, mica, accessory garnet, and tourmaline. Incomplete dissolution was obtained using microwave digestion, with maximum recoveries of 90.25 ± 0.06% and 88.90 ± 0.04% for Nb2O5 and Ta2O5 respectively. Complete dissolution using Li2B4O7 resulted in recoveries of 98.5 ±0.2% Nb2O5 and 100.4 ± 0.3% Ta2O5.

Jan 1, 2012

By d&apos, E. Appolonia

A construction project is successful when all parties contributing to it are winners. It is not a success when there are winners and losers. Con­tractors, engineers, suppliers and equipment developers, and especially owners, each can contribute and benefit from a revaluation of attitudes and contacts from planning to final payment. The Deep Foundations Institute was initiated with this as its major purpose. The help of educators is essential to promote this with the next generation. The Association of Soils and Foundations Engineers has developed guides for "Mediation Arbi­tration of Construction Contracts."

Jan 1, 1985

By Li Huimin

In this paper the step of determining the property index and the program of mixture ratio design of stabilizing agent in deep foundation construction are presented. According to the principle of computer simulation, the model and the method of computer simulation for optimum mix design are set up. Also, the precision of simulation results has been estimated and verified experimentally.

Jan 1, 1991