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The development of economical and effective treatment processes for solid and aqueous waste is a critical issue facing the mining industry today. Cyanide, nitrates and acid rock drainage are environmentally sensitive effluents that require treatment or containment for acceptable disposal. In situ biotreatment processes are an emerging technology (Thayer) for cyanide oxidation, denitrification, sulfide mineral alteration and metal re- mineralization. Biological cyanide oxidation is competitive with chemical treatment processes (peroxide, alkaline chlorination) for process solutions, spent ore and tailings detoxification. Microbial denitrification treats mine waste contaminated with nitrates from blasting, processing or nitrification of the host rock. Bio-alteration of sulfide minerals and metal re-mineralization may present the most cost-effective and environmentally acceptable method of dealing with sulfide tailings and leachate solutions. Field test programs for cyanide bio-degradation and denitrification of spent ore and process solutions were designed and run at two mines. Although the treatment bacteria and the application processes are similar, each waste presented site-specific problems for adapting the biotreatment processes. Some of the site problems include climate, ore geochemistxy, field bacteria production, waste microbiology and application engineering. This paper compares treatment design and results for cyanide oxidation and denitrification in heap detox treatments.

Jan 1, 1992

By A. Palit, M. K. Mohanty

This investigation has concentrated on optimizing the newly developed Pansep linear screen and developing empirical models to predict the screening performance. Most empirical models developed in the past to predict the performance for industrial screens are suitable for the vibratory screens. Understandably, these models are deficient in predicting the performance of linear screens due to the difference in their operating principle. Thus, the main objective of this study has been to develop empirical models suitable for linear screens to predict the partition coefficient for a given size fraction as a function of the aperture size. The inadequacy of the conventional model equation originally developed for vibratory screen has been demonstrated and a modified equation developed to predict the partition coefficient as a function of the normalized mean particle size (d/d50c). In addition, new model equations have been developed for linear screens to predict the screening efficiency as a function of the separation size(d50) and to predict the separation size as a function of the screen aperture. It is believed that these model equations will be useful for the plant operators in selecting the mesh panels of correct aperture size and in predicting the product size distribution based on the selected aperture size.

Jan 1, 2003

By Wayne P. Myers

Electricity, as normally thought of by a layman's definition, is a man- made force that has no color, no odor, is not visible, cannot be heard, yet man can control it and make it perform his work for him. A person dare not cheat on it, for it then will master him. It has laws, rules, and regulations that must be strictly adhered to if it is to perform in the safest, most reliable, and economical manner. In the early days of coal mining the power source was man himself. Later man employed steam and compressed air to reduce his muscle power requirements needed in the extraction of coal. By the turn of the 20th century, electricity had become the most common source of power for the coal industry. Steam and compressed air are still found in use in isolated cases today for specific applications; however, they are rapidly being replaced by electricity. Electrical laws and regulations are quite extensive and somewhat complex for the proper generation and use of electricity. Man-made laws, rules, and regulations for the care and handling of electricity, designed for man's safety, are rigidly enforced by Mine Safety and Health Ad- ministration (MSHA), as well as the various state departments of mines.

Jan 1, 1981

By R. C. Richardson

Barite Worldwide barite production for 1985 decreased 1.3%, while US barite production increased 1.4%, according to US Bureau of Mines statistics. The increase in US production is attributed to heavy demand for oil and gas drilling during the first quarter and an unrealized heavy expected demand in oil and gas markets for the last quarter. Nevada accounted for 82.1% of the 807 kt (890,000 st) of barite produced in the US last year, according to the Bureau. Other producing states were California, Georgia, Illinois, Missouri, Montana, Tennessee, and Washington. In 1985, the US imported 1.8 Mt (2 million st) of crude barite and 64 kt (71,000 st) of ground barite. China led the way with 43.3% of the total. Imports from India accounted for 21.6%; Morocco, 15.5%; and Thailand, 5.6%. The 1.8 Mt (2 million st) of crude barite imported is an 18.8% increase over 1984. Apparent consumption of barite for 1985 was about 2.6 Mt (2.9 million st), a 15.7% increase from 1984. Due to very low drilling rig activity during the last quarter of 1985, actual consumption is probably less as crude barite inventories at mines and plants increased. According to the Bureau, 90% of barite consumed in 1985 was for the oil and gas market. Paints, rubber, glass, and other chemical uses consumed the other 10%. With the price of oil falling dramatically early in 1986, the outlook for oil and gas drilling looks to be significantly lower than 1985. This lower demand for barite, coupled with the high year-end inventories, should lower both imports and domestic production. Significant lower prices on imported barite are expected, especially from China, Morocco, and India. This also could further lower US production of barite this year.

Jan 5, 1986

By Jim Baumann

Deposited millions of years ago in irregular paleokarstic channels, Jamaica’s extensive bauxite deposits provide good quality ore for alumina production and subsequent aluminum smelting. Bauxite mining operations are critical to the Jamaican economy. It accounts for a large percentage of Jamaica’s export earnings. Bauxite production in Jamaica accounts for about 10% of the world’s output each year. Bauxite deposits in Jamaica lie close to the surface. They can be extracted using standard surface mining techniques. The deposits occur in scattered pockets across the country’s rugged landscape. So it was necessary for two of the country’s major mining and refining operations to implement cost effective methods for the acquisition and management of bauxite reserves and surface ownership distribution rights.

Jan 1, 2002

By G. C. Van Bever, J. J. Zaluski

Introduction The Surface Mining Control and Reclamation Act (Public Law 9587) (hereinafter the "Act" or "SMCRA") passed by Congress in August 1977 represents a comprehensive federal scheme for controlling surface coal mining and the surface effects of underground mining through permitting requirements, performance guidelines and reclamation planning. While the provisions of the Act have been the subject of numerous legal challenges and court battles over the years, it is difficult to identify a more controversial program within the Act than the provisions for designating lands as unsuitable for surface coal mining operations. The lands unsuitable designation process provides for the acceptance and review of petitions submitted by citizens or organizations seeking to have specified land areas designated unsuitable for all or certain types of surface coal mining activities. In filing these petitions, the interested parties or petitioners are required to make allegations about potential adverse impacts on people or the environment and submit evidence supporting their allegations. In 30 U.S.C. § 1272, Congress provided that "[a]ny person having an interest which is or may be adversely affected shall have the right to petition ... to have an area designated as unsuitable for surface coal mining operations." Under the Act, an area can be designated as unsuitable where the mining operation will (1) be incompatible with existing state or local land use plans, (2) affect fragile or historic lands, (3) affect renewable resource lands where mining operations could result in substantial loss or reduction of long-range productivity, or (4) affect natural hazard lands where such operations could substantially endanger life and property. In enacting SMCRA, Congress mandated that each state establish a process to determine which, if any, lands within the state are unsuitable for all or certain types of surface mining operations. In response to this federal legislation, the Kentucky General Assembly adopted a state regulatory program for surface mining that included provisions direct¬ing the Secretary of the Natural Resources and Environmental Protection Cabinet to establish a program for designating lands as unsuitable for surface mining as required by the Act. In recent litigation in Kentucky, several environmental groups filed a lands unsuitable petition, later joined by the University of Kentucky, challenging a proposal by Arch Mineral Corporation to surface mine over 3 million tons of recoverable coal. The petition sought to designate over 10,000 acres of land adjacent to Arch's proposed operations as unsuitable for surface mining operations, basically alleging that the mining would disturb an outdoor laboratory. The filing of the petition activated Kentucky's regulatory scheme for reviewing lands unsuitable petitions that can result in an absolute prohibition against surface mining on the petitioned land for historical, environmental and other related reasons. The designation process involves vague petition requirements creating a situation that Arch argued is devoid of constitutional due process and subject to abuse by the petitioner on many fronts. Arch maintained that the lands unsuitable regulations do not grant adequate protection to Arch's legitimate property rights under the due process clauses of the United States and Kentucky Constitutions and are thus void and unenforceable. The entire process resulting in a decision on the petition took just under 12 months in the Arch case, and although Arch was ultimately successful in preserving its right to mine, Arch's surface mining permit was held up for this period of time. This delay led to the cessation of mining operations by Arch and the idling of over 250 workers. This paper will review the lands unsuitable designation process and the significant implications the process has for existing surface mining operations, currently proposed operations and even those long-range operations not yet contemplated. Special emphasis will be given to Kentucky's lands unsuitable program. Finally, the recent litigation involving Arch Mineral Corporation and its effort to surface mine 81.5 acres of Arch controlled property will be utilized to illustrate this very unusual regulatory scheme. Regulatory background Chapter 30, Subchapter F of the Code of Federal Regulations (C.F.R.) promulgated to implement the provisions of SMCRA, requires that each state establish procedures under the state's surface mining program for designating non-federal and non-Indian state lands as unsuitable for all or certain types of surface coal mining operations. 30 C.F.R. § 764.1. The C.F.R. establishes minimum standards for state lands unsuitable programs and sets out requirements for filing a Lands Unsuitable Petition (hereinafter "LUP"), processing LUPs, decision-making guidelines and hearing requirements. Kentucky has adopted regulations providing for the implementation of the lands unsuitable process as part of the state's regulatory program under SMCRA. The following discussion summarizes the principle components of the Kentucky lands unsuitable program.

Jan 1, 1993

By M. A. Qianjie

The problems of coalmine safety in china remain unsolved for decades. Starting with the description on safety status quo of coalmine in china, different existing analysis and measures discussed for the safety problem solution of coalmine china. With the consideration of system thought in mind, the author present with a unique systematic reason analysis method on such actuality--individual analysis and general analysis--each for its particular purpose. Upon such cause analysis, construction of the safety system is made clear and, solutions for such problems provided.

Jan 1, 2006

By J. D. Patsey, G. T. Lineberry

A.E. Hall The authors are to be commended for their attempt to provide a convenient piece of software for preliminary drum hoist specification. This field has received little attention in recent years and is eminently suited to calculation by computer. Unfortunately, there appears to be an error in the calculation of the required rope diameter. The 66-mm (2 5/8-in.) rope selected is oversized for this application. Wire rope weight and breaking strength are related to the rope diameter. For a round strand rope

Jan 8, 1987

By A. E. Hall

The authors are to be commended for their attempt to provide a convenient piece of software for preliminary drum hoist specification. This field has received little attention in recent years and is eminently suited to calculation by computer. Unfortunately, there appears to be an error in the calculation of the required rope diameter. The 66-mm (2 5/8-in.) rope selected is oversized for this application. Wire rope weight and breaking strength are related to the rope diameter. For a round strand rope

Jan 1, 1988

By H. J. Zhang, W. Wui

With the adoption of market-oriented economic policies, Chinese non-ferrous metals industry has gained remarkable progress. The continuously increasing domestic demand for non-ferrous metals, however, calls for more import of raw materials in short supply, such as copper concentrate and bauxite. As an alternative for balancing the shortage and assurance of more stable mineral supply, direct investment in oversea mining project has come to the agenda. This paper discusses the computer-assisted method used for evaluation and comparison of potential mining projects.

Jan 1, 1996

By G. Tapia, R. J. Kelley

Empresa Minera de Mantos Blancos S.A. operates two copper mines in Chile: Mantos Blancos and Mantoverde. Oxide ore is processed by acid leaching followed by SX-EW to produce copper cathodes. In order to define the leach process adequately for each ore, an extensive metallurgical testwork program was carried out during the feasibility study for each of these projects. A combination of heap and dump leaching was selected for Mantoverde, while a modification to the existing vat leach operation was selected for Mantos Blancos.

Jan 1, 1998

By L. M. Anisdahl

Ventiflex is a flexible ventilation duct system with a global market within mine and tunnel ventilation. The system is distributed in a wide range of qualities and dimensions. It is very important that ventilation systems are designed correctly in mines and tunnels. An incorrectly dimensioned system might result in bad air quality and too high costs. The objective of this study has been to assess some important design parameters for ventiflex comprising the friction loss factor for the duct wall itself, as well as the shock loss factors and the leakage factors for the different couplings systems. This has been obtained by carrying out a large scale experimental program on ducts with all the three different couplings: Velcro, zip and steel-ring. Pressure profiles and air flow rates have been measured, and based on these data the different factors have been calculated. The following results have been obtained: A friction factor l = 0,012 (K = 10) for the duct wall, a shock loss factor z = 0,0125 for velcro- and zip couplings, a shock loss factor z = 0,005 for steel-ring couplings, and a leakage factor f* = 0 mm2/m2 for all three coupling types. The latter result proves that no leakage is possible for a correctly installed duct with proper alignment. The results also confirm that ventiflex complies with class S, or better, according to the SIA-norm. However, whether ventiflex should be designed as class S, A or B according to the SIA-norm, depends on the particular application.

Jan 1, 2009

By W. Stark

Many developing countries with little or no previous environmental regulation are now promulgating air quality regulations which require facilities to demonstrate compliance with both process parameter based emission limits and ambient air quality standards. For many companies with operations in developing countries, an air quality compliance program at the facility level is lacking and these companies have very little background information to work with in developing a program for assessing and maintaining compliance. This paper will present a methodology for development of a comprehensive air quality compliance program for operations located in developing countries with new environmental regulations. The experiences of the authors in developing an air quality compliance program for a mining operation located in South America will be used as a basis. A program for meeting new air quality requirements can be developed in seven steps. The seven steps are: (1) regulatory review and project scope; (2) design and implementation of a baseline air quality monitoring program; (3) site visit, (4) development of a complete air emission inventory; (5) dispersion modeling; (6) compliance analysis and compliance plan; and (7) project completion.

Jan 1, 1998

By S. J. Jung

The stability of underground openings for deep mines is critical, since incorrect orientation or geometry of shaft, stope, and accessways often results in the failure of openings due to high stress concentrations. Current state-of-the-art procedures for the design of underground openings are largely based on rules of thumb, experience, and trial and error. Rules of thumb are invariably based on the past experience of the designer and may not remain optimal as the depth and complexity of mine workings increase. Often, as conditions change, and as the interaction between geology, in-situ stress conditions, and mine openings grows more complex, the cost of maintaining structural integrity becomes prohibitive. Existing design procedures for deep mines are rapidly becoming inadequate as mines are worked at greater depths. For example, in the Coeur d' Alene Mining District, several million dollars are spent for inspection, repair, and maintenance on a regular schedule, largely as a result of inadequate design. In these types of situations, it is of critical importance that a new design methodology be developed for the layout and design of underground openings.

Jan 1, 1994

By Arthur E. Belton

Ever since the industrial Revolution both major and small companies have put much emphasis on the use of incentives to compensate top management for extra effort and extra skill. For many years industries have also provided hourly rate employees with incentive plans. More recently incentive plans have been extended to include the "front line" supervisors. Many companies have what are called Christmas bonus or profit-sharing plans. The incentives for foremen in mining, which we shall discuss, differ from such bonus plans in that the incentives are paid on a definite measured performance for each individual, and thus directly reflect his effort and skill. What is the objective for paying incentives? The objective for any part of an industrial Engineering Program is to increase productivity and reduce unit cost. The unit cost must include the entire cost of the program. From what base do we start an incentive plan? One should think of art incentive program as the top rung of the Industrial Engineering ladder. Therefore, a company must take several steps before reaching this top rung. The following steps are necessary:

Jan 1, 1960

By J. W. MacDonald

PROPERTY AND PRODUCTION: Around 100 Million Tons of Recoverable Coal are available from the approximate 10,000 acres allocated to the mine. Over 1300 acres of surface land holdings extend well beyond the limits required for plant site, storage tracks, water supply reservoir, settling ponds and waste disposal. COAL: Extensive core drilled testing confirmed the early indicated high quality of the #6 Seam Washability data show less than four percent of the' coal seam required removal to provide a superior product for the available market. PREPARATION PANT DESIGN: The limited needs enabled Preparation Plant Design to meet the requirements without inclusion of novel equipment. The simplified needs afforded ample opportunity for considering increased automation where advantage or economy was antioipated. Plant design included protection of opportunity for pre-drying in advance of air cleaning the fine coal and accommodations for addition of Dense Media separating equipment in event warranted or required by future market changes. Protection is also afforded for addition of Raw Coal Storage accommodations in event warranted. Figure I shows the Preparation Plant Flow Sheet.

Jan 1, 1961

By A. C. Smith

Although it is only utilized in a few U.S. longwall mines, a bleederless ventilation system can be an effective spontaneous combustion control method in mines with a demonstrated history of spontaneous combustion. In order to provide insights for the optimization of bleederless ventilation systems for U. S. underground coal mines, a computational fluid dynamics (CFD) study was conducted to model the spontaneous heating in longwall gob areas with a bleederless ventilation system. A single longwall panel with a bleederless ventilation system was simulated, and typical ventilation data for a longwall mine was used in the simulations. The permeability and porosity profiles for the longwall gob were estimated using a geotechnical model and were used as inputs for the CFD modeling. The effects of gob permeability and resistance of the collapsed entries on the spontaneous heating were studied. The effectiveness of nitrogen injection to prevent spontaneous heating in the gob was also examined. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.

Jan 1, 2008

By D. G. Krige

Sampling data from large mined out areas of, existing Witwatersrand mines is split into areas accepted as 'mines' and used to provide for each mine the equivalent of a number of sets of borehole values as well as the follow-up 'actual' value. This data is used to establish the spatial structures on a macro scale between 'mines' for grade as well as variance and the suitability of the three-parameter lognormal model Is tested for the borehole and 'mine' frequency distributions. A comprehensive range of borehole valuation techniques is then applied to a large number of borehole sets on an individual mine basis. The results for each technique are then compared with the corresponding follow-up 'actual' values for these mines. After normalisation via the three- parameter lognormal model the estimates are also correlated with the 'actuals' to define any conditional biasses and to establish the observed error distributions and error variances of the estimates. On this basis the various techniques are rated for their relative efficiencies and the significance of the advantages gained.

Jan 1, 1992

By Hasan Sevim

A computerized heuristic model for an efficient and economic design of belt haulage networks in underground coal mines is discussed. The model is versatile, easy to use, and is valid for all mining methods singly or in combination. It may be used to design new networks or to analyze existing networks. The input data required are 1. maximum production rates from a section, 2. probabilities of production rates, 3. equipment costs, and 4. data necessary for network coding to represent different cases. The objective function is the "expected minimum cost per ton of coal hauled" while meeting production requirements. The output includes belt width, motor horsepower, bin size etc. and also values of operating parameters for each belt such as belt speed, effective tension, power consumption etc. A detailed account of the cost involved is also provided for each unit as well as for the entire network. Description of the model and an example of the design of a belt network in a mine with two longwall and four development sections are presented.

Jan 1, 1986

By Firoze E. Katrak, John R. H. Black, Paul R. Ammann, Michael J. Loreth, Servi. Italo S.

Germanium is produced primarily as a by product from zinc concentrates. The important sources of gallium are alumina ores (bauxites) and zinc concentrates and residues from zinc processing. In addition, gallium as well as germanium may soon be recovered from a depleted copper mine near St. George, Utah. The major uses for germanium are in semiconductors, lenses in infrared optical systems, catalysts, and gamma radiation detectors. The major markets for gallium are in light-emitting diodes, solar cells, laser diodes, integrated circuits, microwave devices, and magnetic bubble memories. CRA projects a healthy growth in the demand for both metals. However, the role of scrap metal will continue to be important over the next decade, thus decreasing the overall demand for primary gallium and primary germanium. This paper summarizes the key elements and the economics of the markets for germanium and gallium. Much of the information, such as plant-by-plant costs of production and estimates of consumption by end use for various countries is from proprietary databases of Charles River Associates.

Jan 1, 1986