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The objective of this study is to classify ore and waste in a selected mine. The support vector machine, was used for the classification purpose, is applied to a zinc ore body in a skarn deposit located in the central region of the Peruvian Andes. The input parameters used for the model are spatial coordinates and the lithological information of the ore body. The input data was divided into training and testing data sets and the performance of the model was tested using the testing data set. The results show that more than 76% of the data could be properly classified by this method. The ore waste maps of the deposit was then developed using SVM model. From the result it was observed that a comparatively very few number of cells classified as ore. The ore is concentrated in small lodes at the middle of the volume of study, and not uniformly distributed throughout the study area. The lithological map of the deposit was also constructed as it was used as an input parameter for the SVM model. The indicator kriging was used for generation of lithological map of the ore body. Key word: Ore waste classification, Support vector machine, Indicator kriging, Confusion matrix.

Jan 1, 2008

By W. W. Koczkodaj, J. Partyka

Beat exchange in an open air-water system is considered. The system incorporates a vertical cooling tower, and a horizontal multi-stage spray chamber with unlimited number of stages. Mixing of two streams of both water and air is permitted. A spread-sheet implementation estimates temperatures of outgoing water and air for given mass flow of water and air, factor of merit for heat exchangers, barometric pressure, wet- and dry-bulb temperatures, and the temperature of incoming water.

Jan 1, 1987

By R. V. Ramani, J. Qin

During the mining process, the in-situ material is broken into different size ranges, from very large pieces to very fine particles. Some of the fine particles become airborne. In underground coal mining, airborne respirable dust is associated with health and safety of the miners. The amount and size distributions of airborne dust are important parameters to effective dust control measures. The design of underground mine experiments, including sampling procedures and sample analyses methods to determine these parameters are presented in this paper. A total of fifteen continuous miner cuts were sampled. The amount of dust generated during the cutting process and the relationship between total and respirable airborne dust concentrations and amounts are examined. The amount of respirable dust airborne is on the average only 0.016% of the respirable dust generated. On the average, 61% of the total airborne dust measured is in the respirable size range. The amount of respirable airborne is on the average 36% of the respirable size fraction in the total airborne dust. For equal proportion of rock and coal material cut, rock contributes about twice as much fines (=0.22 mm) as coal. Additional fundamental research is necessary to further the understanding of the airborne propensity of respirable dusts in mine atmospheres.

Jan 1, 1989

By J. W. Choung, J. A. Finch

Acid rock drainage (ARD) is a recognized environmental challenge facing mining industries. An ambient temperature ferrite (ATF) process has been investigated for treating ARD. Most nonferrous metal and calcium ions present in typical ARDs were found to be detrimental to the ATF process. Three approaches were examined, including C02 aeration, addition of complex agents and use of magnetic seeds. By introducing magnetic seeds in the ATF process, the interferences were minimized and all the precipitates formed with lime neutralization were magnetically recovered from a simulated ARD. The residual concentrations of major metal ions in the treated water were environmentally acceptable. The XRD pattern confirmed the spinel ferrite crystal structure of the products

Jan 1, 2000

By J. C. Yingling, J. Sottile

This paper addresses detailed models of the temporal pattern of material flows produced by longwall mining units and procedures for inferring the parameters of these models from field data. First, a model is established that predicts material flows referred to shearer position and cutting element. This model is comprised of trend and fluctuation components. The trend component, which is invariant between repetitions of the cut cycle, accounts for deterministic effects on the flow pattern, such as web depth variation as a function of the cutting operation, systematic tendencies for seam height and cutting speed variations along the face, changes in the relative velocity between the shearer and face conveyor, etc. The fluctuation component models random effects on material flow and employs time series approaches. Subsequently, a method is given for converting the positionally-referenced flows to temporally-referenced flows. The model serves as a basis for generating detailed, accurate computer simulations of material flows from longwall units. As such, it provides a more rigorous foundation for analysis of cutting procedures and outby materials handling systems in longwall mines.

Jan 1, 1994

By Jiang Su, Alan Bloodworth

"Composite sprayed concrete lining (SCL), consisting of two layers of permanent sprayed concrete separated by a layer of spray-applied waterproofing membrane, represents the latest development in SCL tunneling, but presents several challenges to designers. This paper aims to address the following issues: (1) how to simulate composite action, (2) behavior of a composite SCL tunnel, and (3) how to utilize composite action to achieve lining thickness efficiency. It firstly sets out the background to the composite SCL concept, and then presents a strategy for numerical investigation. The main part of the paper is the presentation and discussion of the simulation results, focusing on the lining deformation, load sharing and the safety margin of both linings. Interface stresses are also examined. It is found that significant secondary lining thickness reduction may be achieved by utilizing composite action. Challenges for the design of composite SCL tunnels are briefly discussed at the end. INTRODUCTION Sprayed concrete lined (SCL) tunnelling has seen rapid development over the last twenty years in the UK (Su 2013). One of these developments has been the replacement of traditional sheet membrane and cast in situ secondary lining with innovative spray applied waterproofing membrane and sprayed secondary lining system, which has been adopted in recent major projects, such as Crossrail (Pickett 2013), and brings many benefits to the construction (Dimmock et al. 2013). The combination of sprayed primary lining, spray applied waterproofing membrane and sprayed secondary lining is perceived to provide a structurally efficient lining system that outperforms the traditional lining system, which consists of sacrificial primary lining, sheet waterproofing membrane and cast in situ secondary lining. The claimed benefits in structural performance arises from the composite action between the sprayed primary and secondary linings via the spray applied waterproofing membrane, which produces a much stiffer cross-section and therefore a more efficient use of materials. Early investigations on the design of composite SCL tunnels were carried out without (1) definite and reliable long-term interface parameters, (2) a verified numerical modelling technique, or (3) consideration of different stress histories between primary and secondary linings (Thomas and Pickett 2011, Marcher et al. 2011). This paper reports the findings from a numerical parametric study on a typical composite SCL tunnel with varied secondary lining thickness. The results show that the true benefit of composite lining arises from the optimisation of the lining thickness (stiffness) ratio between the primary and secondary linings to achieve secondary lining safety and thickness efficiency at the same time."

Jan 1, 2016

By M. C. Fuerstenau

With increased emphasis on controlled blasting, which is the first and least-costly stage of comminution, ore grindability and plant throughput can be increased by 5% to 10%, and energy savings of up to 10% appear possible. Crushing and grinding efficiencies are presented for ore blasted under regular and adjusted field conditions. An economic analysis of drilling and blasting through crushing and grinding is presented, suggesting that cost savings approaching 10% may be achieved

Jan 1, 1997

By Bryan A. Bartley

About 1,000 machines around the world are breaking rock and hard abrasive materials by a very economic, high intensity, autogenous process, but this method is largely ignored by the mining industry. This vertical shaft autogenous impact crusher has impact velocities around 70 m/s, which compare with those of Cascade and SAG mills of up to 10 m/s. The autogenous impact, breakage processes are all at higher intensity levels and the products reflect this difference. The topic of liberation is breifly considered. A series of tests with a laboratory scale machine are reported to illustrate a number of the characteristics of the process. This paper highlights topics for further evaluation and research.

Jan 1, 1992

By Marcus M. Key

Silicosis among metal miners is an ancient disease, probably as old as mining itself.' However, the primitive forms of mining were not productive of much silica dust, and the short life span of slaves used in mining probably precluded the development of more than a few sporadic cases of silicosis. Early diagnostic terms of miners' asthma and miners' phthisis suggested an occupational relationship and a tubercular component, but little attention was given to silicbsis until the turn of this century when epidemics of silico-tuberculosis arose due to the great expansion of the mining industry in the United States, especially silver and gold mining. The expansion was accompanied by mechanization and the introduction of pneumatic tools, which generated increasing amounts of fine silica dust. Mining communities were crowded and hygiene was poor.' The tubercle bacillus would probably have flourished even without the predisposition of silicosis.' As is so often the case in occupational health, biostatistical analyses first called attention to the problem, and environmental-medical studies later confirmed its existence. The bio-statistical analyses were occupational mortality statistics compiled by the Prudential Life Insurance Company in 1907, showing evidence of excessive mortality from tuberculosis and relationship to dust exposure. I The

Jan 1, 1971

By Bruno C. Boik

INTRODUCTION Cost Management is the evaluation and control of project scope, budgets, and costs with the objective to minimize costs and maximize the benefits to be derived from the use of project resources in conformance with Criteria stipulated or approved by the Owner. In order of importance, Cost Management is one of the most prominent Project Management functions because of its impact on the financial success of the venture. Cost Control and Cost Accounting are essential parts of Cost Management. The principal objectives of Cost Control are to monitor project commitments and expenditures, and measure performance for the detection of variances from acceptable standards and from control budgets so that timely action can be initiated to minimize costs. Cost Control is evaluation of current costs and projection of future costs, rather than the reporting of actual costs. Cost Control is not Cost Accounting. The primary objectives of Cost Accounting are the determination, classification, analysis and reporting in useful detail of actual costs. Following are some considerations on Cost Management and Cost Control as practiced by Owners and Contractors of industrial projects, Mining and Metallurgical projects in particular. COST MANAGEMENT Functions Conforming with the requirements of Owner's Criteria, the principal Cost Management functions are to • evaluate estimates of project costs and establish budgets for a scope of work and schedule; conversely, evaluate the scope of work that can be executed most effectively within a budget and schedule. • promote investigations and comparative evaluations of alternate designs and plans to find the most cost effective way to execute a project and minimize its operating costs. • based on Cost Control and Cost Accounting input, evaluate and initiate appropriate actions to correct deviations from approved budgets. assess project economics, the effect of changes on project economics and, if necessary, revise Project Criteria to modify their impact on costs.

Jan 1, 1986

By Chris Mills

El papel de la separacion gravimétrica en la industria minera es brevemente considerado en perspectiva. Las pruebas e intentos de laboratorio y mineralógicas para el diseñio de los procesos gravimetricos son examinados poniendo especial énfasis en la selección de la tecnologia del proceso. Es tratado y comentado el material disponible en equipos para pequeña escala y trabajo de pruebas-piloto, particularmente en relación a la escalacion y a la adquisición de datos precisos y fiables. El transporte del comportamiento de los datos desde la planta piloto a la planta a escala es igualmente explicado. Son resefiados todos los tipos de equipos a escala total existentes para la separacion gravimétrica, poniendo de relieve las unidades de alta capacidad. Es considerada la disposicion de la planta y la seleccion de 1os equipos auxiliares.

Jan 1, 1982

By Vernon R. Degner

The past two decades has seen the application of the mechanical flotation machine, originally developed primarily for metal1iferous ore beneficiation, increasingly applied to cleaning coal in the 28x0 T. Mesh size range. Internal cell hydrodynamic studies of mechanical flotation machines of all sizes, as well as computer aided modeling studies of flotation kinetics has, within the last five years, established a basis for optimizing coal flotation circuit design and machine operation, and has a1 so pointed a way toward improvements in mechanical flotation machine design for the future. Consideration of the trend toward increased fines produced by current mining techniques, as well as the environmental need for a progressively cleaner product, lends support to basing the design of the mechanical coal flotation machine of the future on finer feed; below 100 microns in size. Future types of mechanical flotation machines, which may satisfy the fine coal cleaning requirements for a significant improvement in product grade while maintaining the combustible recovery levels of current technology, are discussed.

Jan 1, 1988

By G. F. Friel, J. C. Edwards, C. C. Hwang

In the implementation of a mine fire alarm and location strategy, the Interpretation of the fire signature Is Important. Smoke and CO are the two dominant fire signatures, and many mine fire detection systems utilize sensors which respond to smoke or CO through a diffusion mode or a mechanical pump mode. The fire signature may be modified during its transport along airways and at crosscuts. The modification occurs through dilution of the contaminants. In this Investigation, computer codes were employed to compute the effects of contaminant dilution on the contaminant signature when a straight flow passage has one dead-end crosscut. The model predicted the airflow within always and the entrainment of contaminants into the crosscut from the airway. One application of the model is to determine the most suitable location for CO detectors for early mine fire detection.

Jan 1, 1995

By W. P. Diamond, A. C. Smith, J. A. Organiscak, T. P. Mucho

The U.S. Bureau of Mines examined bleederless ventilation practices to evaluate their use as a spontaneous combustion control measure in U. S. coal mines. Results indicate that restricting airflow into mined-out areas (bleederless ventilation) is recognized worldwide as a spontaneous combustion control measure. However, ventilation practices commonly used to limit airflow to mined-out areas are not easily applicable to United States mining conditions, systems, experience and regulations. The types of bleederless ventilation systems used throughout the world and the spontaneous combustion risks associated with these systems are discussed. Primary design considerations for bleederless ventilation consist of the interaction of ventilation practices, methane drainage, ground control, seal construction and mine monitoring. Technological improvements needed for U.S. application of bleededess ventilation are also discussed.

Jan 1, 1995

By E. D. Goddard, D. S. Murphy

Acid resistance, zeta potential and ESCA (electron spectroscopy. for chemical analysis) experiments were performed on emperador marble and four calcium carbonate samples (onyx calcite, travertine calcite, Iceland spar calcite and aragonite). Six fluorine-containing reagents were used to treat the surfaces of these materials: magnesium hexafluorosilicate, zinc hexafluorosilicate, sodium fluoride, zinc fluoride, strontium fluoride and stannous fluoride. The acid resistance of treated samples proved to be much higher than that of their untreated equivalents. The isoelectric point of treated samples approaches the isoelectric point of fluorite. Also, the fluorine content, as measured by ESCA, of a marble surface treated with magnesium hexafluorosilicate is much higher than that of an untreated sample. The binding energy off of fluorine and calcium the treated marble is consistent with the formation of calcium fluoride.

Jan 1, 1994

By E. Watkins, R. Kimutis, H. Dougherty

Gas wells have often intersected mining resources, but unconventional shale well drilling has more recently challenged mines to balance the risk of interaction due to higher pressures and larger quantities of gas. Full extraction mining, such as the longwall method, induces ground movement that may influence the casings if wells are drilled within the mining area. The possibility of a casing shear would lead to the risk of unplanned gas migration into the mine. This has the potential to quickly overcome the ventilation system and reach the explosive range which, if ignited, can have catastrophic consequences on the health and safety of underground workers. The utilization of network software to model mine ventilation is a common practice in the mining industry and can assist with a well breach scenario. This work focuses on a well breach in between two longwall panels after second panel mining with gas entering primarily through the gobs of the adjacent longwall panels. Applying the network software Ventsim, a gob zone and ventilation network were created to better understand the distribution of gas within the mine and the limitations and effectiveness of a ventilation system. The model shows both a transient flow simulation and steady state concentrations throughout the mine ventilation system. Using a standard Pittsburgh coal seam longwall ventilation scheme, we find that the system can dilute a significant inflow of up to 700 cfm of methane.

Mar 2, 2022

By D. S. Ramey

In-situ leaching of the oxidized copper mineral resource at the San Manuel mine has proven to be a technically and economically viable method of copper extraction. Although this leaching method has been modeled to predict future production capabilities, the expected magnitude of the ultimate recovery from any portion of the present mine is not fully understood. A closely controlled test has been designed, constructed, and is now operating to determine the rate and magnitude of copper recovery. The test, initiated in June 1992, is scheduled to operate for approximately 18 months. This paper presents an overview of the test design and current results.

Jan 1, 1993

By R. A. Jankowski

Laboratory tests were conducted to evaluate the silica collection efficiency of flooded-bed scrubbers using six different filter panel designs at two operating velocities. Test results indicated that reductions in filter density negatively impacted respirable dust collection. Silica collection efficiency for the least-dense filter was as much as 33 % lower than the collection efficiency of the most-dense filter. At the low operating velocity, the least-dense filter allowed more than 40% of the respirable silica dust in the scrubber intake air to pass through the unit and back into the mine environment. Operation of the scrubber at the higher test air velocity increased silica collection efficiency regardless of the filter panel tested The density of the filter panels also impacted the quantity of air moved through the scrubber, with higher-density filters reducing scrubber airflow. For each filter, the relationship between dust-collection efficiency and air-moving capacity must be considered to determine the overall effectiveness for each mine application.

Jan 1, 2000

By J. E. Hoffman, Corby G. Anderson, T. J. Keefe, O&apos, Suzzann M. Nordwick

Antimony removal has become necessary as it is commonly found in precious metal refractory ore bodies. The Sunshine Mine in Kellogg, Idaho has recovered metallic electrowon antimony from its argentiferous tetrahedrite (Cu2S'Sb2S3) deposits for over fifty years. Recently, Sunshine conducted an intense research effort to improve and modernize its antimony facility. This paper presents information which was learned about the antimony electrowinning processes and the development of a single¬-electrolyte antimony electrowinning technology. The relevant effects of process variables were investigated. The research results and the relevant chemistries involved in metallic antimony electrowinning will be discussed.

Jan 1, 1993

By John Davis Morgan

The uncertain world conditions of the present time require that the United States be prepared to meet: a. all-out nuclear war with attack on the United States b. limited wars (anything smaller than (a.) c. political, economic, and/or psychological warfare. Our present position as a major world power derives in large measure from our free institutions and our great industrial productivity, and our productivity in turn depends on an ever-continuing flow of raw materials from the earth - metals, minerals, fuels, and agricultural products. The United States, with only about 6% of the world's population, uses from one-third to two-thirds of the world's annual supplies of 'most metals and minerals. The United States strategic materials stockpiling program is designed to enhance our national security posture: as stated in the preamble of the Stock Piling Act, to decrease and prevent wherever possible a dangerous and costly dependence of the United States upon foreign nations for supplies of strategic and critical materials in times of national emergency. In times past, the Good Lord himself has ordered some stockpiling. The Book of Genesis in the Bible tells how Pharaoh of Egypt was directed to set aside one-fifth of the produce of the land in each of the seven good years to meet the needs of the seven bad years that were to follow: this would be a stockpile of about two years? normal use. Our cultural heritage often reminds us of the wisdom of stockpiling, as in the case of the stories about the provident squirrels that gather their nuts in an orderly manner in the f all to prepare for the winter's cold. And the old proverb about a bird in the hand being worth two in the bush points out clearly the value of something that is directly at hand.

Jan 1, 1960