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By J. B. Hanlon

In order to protect coal mine owners, operators, and lending institutions from potential environmental liabilities, responsible parties must maintain a thorough understanding of the environmental disposition of the property they control, and the ramifications of impending laws and regulations. The best way to accomplish this is to periodically conduct a Phase I Environmental Audit. The systematic approach of an audit will reveal areas of DOD compliance with SMCRA and EPA regulations which the coal owner and/or operator will be able to use to correct deficiencies and prevent the occurrence of conditions which could lead to permit block, fines, and ultimately reduced productivity.

Jan 1, 1995

By John M. Hill

Automation technology has many facets, some well tested and proven, some yet to be put to the acid test of economic reality. In this paper, we will limit our purview to the former. Consider, if you will, an automated handling system combining high-speed conveyors and automatic devices on-line which not only provide signals for routing and sorting, but also format those signals for the production of manufacturing, inventory, shipping and billing paperwork. This is not futuristic, but practical and a realistic accomplishment. Therefore, the following discussions will address today's challenges not with tomorrow's solutions, but rather, with an established technology which is playing an increasingly prominent role in materials handling systems. Until recently, relatively modest importance has been attached to the timeliness of information feedback from the production or assembly line, warehouse or distribution center. Thus, initial applications of automatic identification equipment focused almost exclusively upon the control of materials flow - that is, routing, sorting, etc. However, these systems have performed successfully and quietly established an enviable track record as reliable materials control tools.

Jan 1, 1973

Allis Mineral Systems' Grate- Kiln system can economically convert low-grade iron ore into high- grade iron-ore pellets suitable as feed material for blast furnaces for making steel. These pellets can also be fed to a direct reduction process for making sponge iron. The Grate- Car system combines the company's [ ] Grate-Kiln system for iron-ore pelletizing and Accar system for iron- ore reduction. The Grate-Car system consists of a traveling grate, a ported rotary kiln and a rotary cooler that are coupled in series. This system eliminates the pelletizing plant's rotary kiln and annular cooler. It reduces the need for some auxiliary equipment. This results in lower capital cost and lower energy consumption. The traveling grate provides that static bed handling necessary for heat hardening pellets before their discharge into the kiln. The ported kiln provides the reducing atmosphere with a more precise means of controlling the kiln axial temperature profile than conventional rotary kilns.

Jan 1, 1997

By Diler Katircioglu-Bayel, Oner Yusuf Toraman, Safak Gokhan Ozkan

Calcite has found many applications in the industrialized countries recently, such as filler for paper, paint, plastics, rubber and food. Furthermore, calcite separates many toxic elements, and thus it is used in water treatment, and it is also used to raise the pH of drinking water. Due to its special features, calcite has been characterized as a useful coating and reinforcement filler for applications. Finer particle size of calcite has been determined to provide improved features for all of these applications. For submicron particle production, wet milling is selected over dry milling to produce finer particle sizes. Wet stirred media mills are also used in many industries. For that reason, this study investigated the effects of operating parameters on particle size reduction in the wet grinding process. The knowledge acquired by this study will allow the finding of optimal operating parameters for a stirred media mill to optimize specific energy consumption and reduce particle size.

By Robert T. DeGavre

I have been asked by the Society of Mining Engineers to present a paper on Inco Limited's Indonesian nickel project as a case study in the financing of large overseas mining projects. I welcome this opportunity It is a story worth telling not only because the project itself represents a significant human achievement but also because there are certain important lessons that can be derived from our experience in financing the project. The paper will be divided into four sections: (i) a brief history of the project, (ii) a critical appraisal of the project's financing plan in terms of the goals that we sought to achieve, (iii) some comments on certain factors underlying the relative success of the financing plan, and (iv) the contributions that the engineering staffs must make to a successful financing plan. The paper will not present a technical assessment of the project since Inco Limited has been asked to submit a series of papers on this subject at the International Laterite Symposium as part of the 108th Annual Meeting of the AIME in February 1979.

Jan 1, 1978

By Stanley Noss

One need be neither an historian nor technologist to recognize that activi¬ties related to the conversion of coal to other usable energy forms have been active for nearly fifty years. The degree of such activity and its evolution to significant commercial proportions has, however, fluctuated widely with world circumstance. For the past decade there has existed both a consistent technology evolution effort in classic R & D proportions, and a mainstream commercial acti¬vity but in rather modest proportions when viewed from the vantage point of world energy needs. But the chain of events wherein it became increasingly obvious that we were in energy trouble irrespective of world politics, spurred alternative energy source activities in the fossil fuels areas. The oil embargo of 1973-1974 made the obvious even more so and provided additional emphasis for the need of such alternatives. Yet the preponderance of these added expenditures and activities (with one notable exception which is the subject of this discussion) has been focused on the intended identification of the best or ultimate process by means of analytical and modest empirical means, whereas our circumstance dictates a bold, higher-risk effort to prove the viability of coal conversion as an industry on a real-time, real-size, real-economics basis. With such proof on hand, industry demands in all related areas will provide the stimulus, motivation and environment for all processes. There is both need and room for many who will compete for a meaningful segment of this new industry which can grow at a rate never seen before in our growth history. The single program in the world today oriented specifically toward the goal of proof of industry viability is the Energy Research and Development Administration's CBF (clean boiler fuels) Program for which COALCON is proud to be the prime contractor.

Jan 1, 1976

By Rafael C. Castro, Paul V. Savard, Kathleen M. Murtagh

Preliminary design is underway for the Massachusetts Water Resources Authority’s (MWRA) next major tunnel program, the Metropolitan Water Tunnel Program (MWTP). The MWTP is the latest part of MWRA’s ongoing efforts to achieve redundancy for its metropolitan water transmission system including its historic deep rock City Tunnel, City Tunnel Extension and Dorchester Tunnels. The MWTP comprises several deep rock tunnels that will be approximately 10-foot to 12-foot finished diameter totaling just over fourteen miles long and ten connections to existing large diameter surface piping and pumping stations. This paper will present an update on current engineering and permitting efforts, packaging schemes, and the schedule to complete the MWTP.

Jun 13, 2023

By J. M. Mutmansky

Procedures for the determination of the operating point that results when a fan is connected to a mine and placed in operation have been a source of confusion for decades. A variety of techniques has been proposed, often to the detriment of the practicing ventilation engineer trying to apply the techniques to the multitudinous mine/fan matching problems encountered in the engineering of mine ventilation systems. This paper proposes some different assumptions and definitions that simplify the solution of problems in determining the operating point. As a result, a set of procedures is provided for determining the operating point of a mine/fan system when the outlet areas of the mine and fan are known. To establish a major simplification in the development of procedures for the determination of the operating point for a mine/fan combination, the authors suggest that the mine pressures be redefined and then used in such a manner that the conservation of energy is ensured. This provides the basis for the recommendation that the fan operating point be determined using the fan total pressure and the system total pressure characteristics. This procedure can be applied to fans in the blower, booster, and exhaust positions equally well and to both single-fan and multiple-fan networks. Another advantage is that the method is applicable to fans with or without an evase.

Jan 1, 1984

By Robert D. Coale

This paper will describe the copper concentrate slurry pipeline and pumping system between the concentrator and the port at Bougainville Copper Ltd. The operations of Bougainville Copper Ltd. are located on the island of Bougainville in the South Pacific. Geographically, it is the northernmost island of the Solomon Group but, politically, it is part of Papua New Guinea. Papua New Guinea is a United Nations Trust territory administered by Australia, having recently been given self-government, with independence scheduled for December 1974. (Fig. 1). The island is approximately 130 miles long by 30 miles wide, with the Crown Prince mountain range forming a spine along its length. The mountains in place are over 8,000 feet high with the mine located on the western flank at an elevation of 2,200 feet. Exploration on Bougainville for copper by Conzinc Riotinto of Australia (CRA) began in 1963 and by 1968, through geophysical, geochemical and diamond drilling methods, an orebody containing nearly one billion tons of ore grading approximately 0.48% Cu. and sane gold had been outlined. Bougainville Copper Ltd., the company operating the mine, is 53.6% wined by CRA, 20% mined by the government of Papua New Guinea with the public Folding the remainder of the shares. The first copper concentrate was produced in early 1972, with production for the first full year, 1973 being:

Jan 1, 1974

By Jacob Mathis, Mark Bradford, Alston Noronha, R. M. True

In June 2022, Louisville MSD completed a 6.5-km (4.0-mi), 6.1-m (20-ft.) diameter CSO conveyance and storage tunnel system located along the Ohio River in downtown Louisville, Kentucky. For large diameter shaft and tunnel construction, drill-and-blast operations among other methodologies were used in close proximity to federal, commercial, and residential properties with no impact to stakeholder infrastructure. s one of the rst maor tunneling proects in Louisvilles metropolitan area, this paper explores Black & Veatchs rigorous geotechnical instrumentation monitoring program that provided uality assurance for local stakeholders and afrmed innovative tunneling solutions can be successfully executed in an urban setting.

Jun 23, 2024

By G. T. Adel, P. E. Richardson, R. Pazhianur

Cathodic protection using impressed current was employed to reduce mill wall wear during ball milling. Wear rates were determined from weight-loss measurements made on four 1-in.-diam mild steel coupons that were installed flush with the interior surface of the mill wall. Grinding tests were conducted on quartz, pyrite and quartz-pyrite mixtures at pH levels of 4.6, 7.1 and 9.2. Cathodic protection was shown to reduce mill wear by 30% to 60%. An examination of the coupon surfaces using scanning electron microscopy showed that cathodic protection greatly reduced pitting corrosion. The presence of a sulfide mineral, such as pyrite, was found to increase the wear rate significantly, possibly due to galvanic interactions. It was also found that the wear rate is significantly higher than the sum of abrasive wear and the corrosive wear, due to a synergistic effect.

Jan 1, 1998

By Douglas W. Huber

During the past decade, a general awareness of the need for and subsequent development of increased safety in United States coal mines has taken place. Government and industry alike were stimulated into accelerating their actions through unacceptable accident statistics and costs (in terms of human misery dollar values). Those of us who work in the United States coal industry are aware of the development of governmental controls on nine safety. Both Federal and State regulations have placed increased responsibility upon mine owners and operators to insure a safe working environment and to provide training for miners. No other industrial group of workers has received such attention or, in our opinion, deserves it more.

Jan 1, 1982

By Dr. Jack M. Gillette

A system of models which simulate surface coal mining operations has been developed for use in mine planning and economic evaluations. Micromodels simulate individual mine operations for equipment selection and mine planning. Macromodels simulate all operations in the complete mine for economic evaluation of reserves. A cash flow analysis model makes a complete discounted cash flow analysis to deter-mine a required coal sales price or return on investment for evaluation of any mining project.

Jan 1, 1978

By Morgan M. Sears, Gamal Rashed, Michael M. Murphy, Brent Slaker

A parametric study was conducted using FLAC3D numerical models to examine the impact of oblique loading on the strength and yield pattern of a stone pillar using two simplified geometry types. In type-1 the side walls of the pillars were assumed to be perpendicular to the roof and the floor, while in type-2 the side walls were assumed to be vertical. These two geometries are frequently used to simplify/model the creation of pillars in dipping mines. Results from the numerical modeling indicate that dipping pillars have reduced strength compared to horizontal pillars, and they are at an elevated risk of failure. Also, an asymmetric failure propagation pattern could be obtained depending on the interaction between the pillar width/height (W/H) ratio, seam dip, in situ stresses and pillar geometry.

By T. W. Martin

The use of conveyors in large, open pit mines and their drawbacks are discussed. Technological developments such as long distance conveyors capable of handling large rocks are explored. The development and testing by the Bureau of Mines of a prototype crib and cable conveyor for handling large rocks are discussed, and possible modifications of the concept for a production model are examined.

Jan 1, 1984

By Richard H. Johnson

White Pine Copper Company, a subsidiary of Copper Range Company located in Michigan's Upper Peninsula, mines a Precambrian sedimentary deposit containing finely disseminated chalcocite, native cop- per and native silver. Silver occurs predominately in certain strata and presently provides a mill head averaging 0.25 ounces per ton. This technical publication traces the development of silver recovery at White Fine beginning in early 1961. White Pine refined copper contains an excess of silver over and above that required to impart Lake Copper properties. The copper does not require electrolytic refining to meet industry purity requirements, nor is there sufficient silver to justify electrolysis.

Jan 1, 1970

By A. G. Mayton, D. H. Ambrose, C. C. Jobes, N. K. Kittusamy

In a systematic study, the National Institute for Occupational Safety and Health (NIOSH) evaluated seat designs in low- and mid-seam shuttle cars during production operations at two underground coal mines in southern West Virginia. The purpose was to support, with additional data, earlier findings that NIOSH ergonomic seat designs (featuring viscoelastic foam padding and lower-back support) may help reduce health risks to operators of coal mine shuttle cars. Eight shuttle car operators evaluated seven seat designs (one already in use in each vehicle and five NIOSH designs) relative to perceived and measured whole-body vibration (WBV) exposure (including vehicle jarring/jolting) and discomfort. Operators’ perceptions using a visual analog scale (VAS) and questionnaire ratings were compared with International Standards Organization (ISO) 2631-1:1985 fatigue-decreased proficiency (FDP) limits and measured WBV levels on low- and mid-seam shuttle cars. Objective and subjective data results indicated that NIOSH seat designs (with added adjustability, lower-back support and improved seat padding) performed better to reduce vehicle jarring/jolting levels and that shuttle car operators favored them over existing seat designs. The NIOSH low- and mid-seam shuttle car seats showed 45 to 77 percent better performance in FDP and 9 to 60 percent better performance overall in operators’ ratings. Considering the VAS results for low- and mid-seam shuttle cars under no-load conditions, operators rated the level of jarring/jolting 18 to 89 percent lower with the NIOSH seats. Reductions in measured vehicle jarring/jolting were 19 to 46 percent for the three-directional vector sum accelerations relative to the existing seats on the low- and mid-seam shuttle cars. Questionnaire responses indicated that operators for both shuttle car models rated NIOSH seat designs as more comfortable overall. Vehicle operators most frequently suggested adding armrests to improve the seats on the mid-seam shuttle car. A suggested improvement for the low-seam shuttle car was to make the seat a better fit for the operator compartment, which would enhance clearance between the operator and vehicle controls and allow for better seat adjustment and operator visibility.

Jan 1, 2009

By Guillermo Krstulovich

Pillar strength is a fundamental variable in the design of room and pillar mining. A number of researchers have investigated the strength of mine pillars by loading cubical, cylindrical and rectangular model pillars to failure in a compression testing machine (1). Several of these researchers have observed an increase in the compressive strength of model pillar with an increase in friction at the platen-specimen interface (2, 3, 4, 5). It has been postulated that the friction prevents lateral expansion of the specimen, thereby exerting a confining pressure at the interface. Seldenrath and Gramberg in their work with cylindrical specimens of limestone and marble noted that the effect of clamping the ends of the specimens, i.e., to restrict lateral movement of the specimen face, was to increase the compressive strength about 10% for marble and from 50-75% for the limestone, as compared to the same type of specimens when tested with the end planes free (6). No attempt was made to determine the confining pressure exerted by the clamps. In recent years, Bureau of Mines has conducted an extensive study, similar to Seldenrath and Gramberg's, with dog bone specimens. The confining pressure exerted by the clamps was determined and an increase in the compressive strength with increasing confining pressure noted (7, 8).

Jan 1, 1970

By R. E. Hamilton

Automation is a word whose meaning has been broadened by popular usage to include any labor saving device. We with restrict our usage to the replacement of human judgement by instrumental measurement and mathematical analysis in the control of industrial processes. Mineral concentration is an area which has resisted automation because of the great difficulty in developing measuring instruments which can exist in the rugged environment and can measure useful properties with acceptable accuracy. This is not the only factor limiting progress, but until recently it has been of over-whelming importance. The development of on-stream X-ray analysers, magnetic flowmeters and nuclear density meters for mineral slurries has eliminated this obvious barrier and is enabling us to locate and attack the less obvious problems which still limit our ability to automate concentrators. If we examine the history of automation in industries which are highly automated we find that it has usually gone through three distinct phases. The first phase has been regulation. This is the simplest form of control and involves manipulating some variable whose value is of no importance in order to maintain the value of some other variable which is important at a constant specified value in spite of disturbances which may occur in other variables which affect it. A simple example is the use of a control valve to maintain a constant flow of fluid in a line in spite of changes in pressure in the vessels at the ends of the line. The position of the valve stem is of no consequence, as long as it is within its operating range. Unfortunately we soon run out of variables which can be

Jan 1, 1971

By J. D. Pitts

The worldwide production of iron ores was approximately 880 million metric tons in 1975. This level is the result of an annual growth rate of nearly four percent during the period 1967 to the present. The high growth rate was particularly significant in that two relatively severe worldwide recessions occurred in 1971 and 1975. The current upturn in world economic growth will probably allow future annual iron ore production growth rates in excess of the four percent figure, and, in fact, the International Iron and Steel Institute (IISI) has predicted that a five percent rate should be realized through 1985. The IISI figures would indicate a 1.4 billion metric tons per year output by 1985 or an increase in current production levels of around 500 million metric tons per year (MMTA)1. Even the more conservative four percent growth rate prediction from historical data would provide an 2 increase over current figures of nearly 350 MA by 1985. A large portion of world iron ore production is being provided by large resource-rich countries with relatively new industrial bases. These countries are typified by heavy export of raw materials such as iron ore and ore products and a large capital investment in the facilities to recover these raw materials. Brazil and Australia are typical of such countries and, indeed, their production of iron ore in the period 1967 to 1973 increased at annual rates of 17 to 30 percent, respectively, The continual reassessment of resources in these and other major iron ore exporting countries such as Venezuela and Liberia would indicate chat these high growth rates may continue for some years to come to meet anticipated world demand for raw steel production.

Jan 1, 1976