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By J. J. Schwoebel

Resource Enterprises Inc. (REI) is exploiting the coalbed gas resource by working in unison with active underground mining operations. At REZ7s pilot project at the Soldier Canyon mine, Carbon County, UT, RE1 has drilled nearly 15.25 km (50,000 ft) of horizontal in-seam and slant boreholes during the initial two years of drilling activity. Produced gas has been sold to a natural gas transmission company on a continuous basis since mid 1983.

Jan 1, 1988

By Bok-youn Kim

Presently, mobile diesel equipments contributes a lot in improving the economical feasibility of underground mining and tunneling operations. Even in Korea, quite a large number of diesel equipments is being applied to the underground workings already. This paper introduced the production procedure, characteristics and evaluation technology on diesel particulate matter(DPM) that is known as a carcinogen For easy measurement of DPM using laser dust monitor, the conversion factor(K) to gravimetric concentration was acquired. The field measurement of DPM was conducted to make a comparison between locally manufactured on-road equipments and imported equipments specially designed for underground use. According to the Government regulation revised h 1996, it was learned that the critical pollutants among the diesel exhaust is DPM instead of NOx which have been considered as a critical pollutants.

Jan 1, 1997

By H. Sevim

This paper summarizes the research effort in simulating the operation of "Underground Coarse-Coal Hydrotransport Systems" (UCCHS). The equipment of the system to be simulated is already optimally selected by using an analytical optimization model. The purpose of the simulation model is to test the performance of the system and to obtain the distributions of operating parameters such as water and power consumption and amount of slurry delivered to the preparation plant. Knowledge of the distributions of these parameters is essential for the efficient operation of the system.

Jan 1, 1987

By Greg Barfoot, K. Payne

Condition monitoring of conveyor belting has become an established tool for maintenance programming, replacement strategies and quality assurance for belt conveyor systems. What is less well known is that the condition of the conveyor belting is usually a symptom of problems in other areas rather than the problem source. This paper presents an overview of the state of the art in belt monitoring and the move towards on-line NDT systems. The use of belt monitoring data as an indicator for overall system design, maintenance and operation is also discussed.

Jan 1, 1996

By J. P. Nairn, C. M. McCulloch

More and more underground mining is being conducted using the long wall method. Likewise, many new surface mines use area or mountaintop removal methods. These methods can have a significant impact on surface and ground water resources. The overall study of the effects on surface and ground water from mining is referred to as the probable hydrologic consequences (PHC) determination of mining and reclamation. Collection and interpretation of information concerning ground water and surface water quality and quantity, as well as detailed geologic analysis, is required to adequately define the impacts of mining. This paper discusses the present day requirements and methodology of preparing a PHC for a large mining operation in the eastern coalfields.

Jan 1, 1997

By B. K. Parekh, R. H. Mehta

The handling of fine coal is an important issue for both the coal and utility industries. Reconstitution of fine coal in the form of pellets or briquettes would be desirable if it could be done economically. This paper evaluates the effectiveness of three binders, asphalt-emulsion, corn starch and Brewex, informing pellets of ultrafine clean coal. It was found that asphalt-emulsion and corn starch were not effective binders. However, the use of Brewex resulted in pellets that exceeded all of the minimum quality requirements for coal pellets.

Jan 1, 1997

By Lynn B. Hales, Randy A. Yncbausti, Rick Smith

Object oriented programming has been developed to model the way we think about the world. It allows higher levels of abstraction, generalization and classification than many other programming techniques. Some tools of object oriented design and programming are encapsulation, classes, inheritance, modularity and reusability. Expert systems have been used for years to implement process control strategies in the minerals industry. Expert systems allow process control knowledge to be expressed in linguistic rules that are processed by an inference engine. Expert systems which employ object oriented design and programming provide new opportunities for real- time process control. The concepts of object oriented programming and an example object oriented expert system are discussed in this paper.

Jan 1, 1992

By Robert M. Cox

The principal factor that must be determined for the effective design of a coal mine roof bolt support system is the maximum stable tension that can be developed with a given bolt assembly in a particular roof rock. There are four basic types of roof bolt anchorage techniques available: (I) the splitwedge; (2) mechanical expansion units; (3) resin point anchors or grouted expansion units; and (4) the cone shell which is placed in a reamed hole. A study of this problem has been made which includes theoretical analyses, laboratory experiments and field tests. A static free-body analysis of each of the anchorage techniques has provided formulas for predicting the anchorage capacity for a particular rock from the results of standard pull tests. The formulas also provide an insight into the anchorage mechanism of technique and allow for a comparative evaluation of the methods for design purposes. The theoretical analyses also indicate clearly the pertinent variables affecting the anchorage mechanism of each method.

Jan 1, 1977

By R. L. Lewis

The White Pine Mine is a large underground copper mine located in the Upper Peninsula of Michigan. A numerical ground water flow model of the White Pine Mine was constructed to evaluate potential engineering controls that would reduce the rate of mine-water discharge after closure. Of the passive controls evaluated, the placement of bulkheads within the mine workings was predicted to offer the greatest benefit, reducing the rate of discharge by as much as 35%.

Jan 1, 1997

By B. C. Darst

Intensive efforts to develop potash use in agricultural production were begun in the US 50 years ago. Early growth was rapid and continued well into the 1960s. Many soils were inherently low in K, so crop responses to fertilization were often dramatic. Deficiency symptoms were common. Per-acre use has continued to increase in recent years, but annual growth rates have slowed. Soil buildup has occurred in some areas. Poor economics in the 1980s have been difficult to overcome. Efforts are now well under way to develop potential markets around the world.

Jan 1, 1987

By R. P. Moran, B. C. Lewis

The objective of this article is to discuss the fundamentals for determining the value of a limestone reserve or operation. The general step-by-step procedure, while prudent, is subject to the various site-specific issues that influence the valuation calculation. The most common methods for determining fair market value of mining lands are: comparable sales, operational analysis, and royalty analysis. An overview of typical eastern limestone mines (both quarries and underground) is presented. Specifically, properties in West Virginia and Alabama are reviewed and the sample methodologies and valuation calculations are presented.

Jan 1, 1991

By M. Paventi, M. J. Scoble, B. B. Mohanty

There is no straightforward and systematic method for adequately measuring blast damage in on-going mining operations. This paper considers various techniques available for the measurement of blast damage, making particular reference to recent underground hardrock mine studies. This paper concludes by indicating the importance of understanding and accounting for geology and emphasizes the need for a robust damage-audit procedure.

Jan 1, 1998

By K. A. Natarajan, Namita Deo

The interaction of Bacillus polymyxa and minerals such as hematite, corundum and quartz resulted in significant surface chemical changes, both on the cell surfaces and on the interacted oxide minerals. After such treatment, quartz was rendered relatively more hydrophobic, while hematite and corundum were rendered more hydrophilic. Biopretreatment was observed to be beneficial in the separation of silica from hematite and alumina by both selective flocculation and flotation. The possible role of bacterial adhesion and metabilites in the biobeneficiation process is illustrated.

Jan 1, 1998

By G. M. Wilemon, J. G. Davis, R. G. Swanton, B. J. Scheiner

The US Bureau of Mines has conducted investigations on extracting phosphate values from wastes generated during the mining and beneficiation of phosphate matrix. These wastes may contain up to one third of the phosphate originally present in untreated ore. Samples of wastes were air-dried and leached using 93% sulfuric acid in the presence of methanol. Evidence for the formation of a calcium sulfate hemihydrate coating that hinders complete dissolution of phosphate is presented. Solid-liquid separations were enhanced when flocculation was effected using poly(ethylene oxide) (PEO) in conjunction with hydroxypropyl cellulose (HPC) or hydroxyethyl cellulose (HEC). A conceptual flowsheet for a proposed process using an acid-alcohol leaching technique is presented.

Jan 1, 1991

By D. S. Choi, H. D. Dahl, D. L. McCain

The paper examines current room and pillar mining practice in the U.S.A. from the standpoint of rock mechanics. Consideration is given to the deformation characteristics of the roof formation and the coal seam as determined in the laboratory as well as in the field. The results can be utilized by the practicing mining engineer to improve current mine design practice.

Jan 1, 1982

By Alexander Filimonov, Yury Bloshteyn

Ventilation of gas mines keeps necessary sanitation and hygienic conditions for labor in mines and increases the safety by dilution and removal of hazardous and dangerous gases in accordance with the safety rules. Several different concepts exist at the present time to design mine ventilation control systems. But technical ideas have been developed inadequately and technological solutions have not been investigated experimentally enough to build a serviceable system. This paper presents a new concept of high- efficiency mine ventilation process control system (MVPCS). The methods of modern system engineering (Kalman, 1969) are used to establish its functional and algorithmic structure. A three level hierarchical principle of system building is considered.

Jan 1, 1991

By J. A. Herbst, Z. Rogovin

In order to develop more accurate procedures for scale-up and design of semi-autogenous grinding mills through detailed mathematical models, a better understanding of the charge motion and rocklball segregation is needed. To achieve this a 0.61 m (2.0 ft) diam by 0.305m (1 .0ft) length plexiglas mill was constructed as a scale model of a commercial SAG mill. Rock motion in the rotating mill was simulated using various sizes of ceramic balls. Quantitative measurements of dynamic angle of repose, water and slurry motion, holdup and size segregation of the charge were taken. In addition, a video presentation (available to the public) was prepared to elucidate charge and water motion at various mill speeds, charge volumes, rocksize distribution, and flow rates.

Jan 1, 1990

By J. E. deMasi

Over the past 12 years, Exxon Coal U.S.A., Inc. has shipped over 150 million tons of coal from two mines, Rawhide and Caballo, located in the Gillette, Wyoming, area. These mines are operated by The Carter Mining Company, a division of Exxon Coal. Shipments have moved to more than 25 electric utility plants in the west, midwest, southwest, and south. The customer plants have represented a wide variety of configurations, sizes. design criteria, emission standards, and operations in different parts of the country. We have learned a great deal about the performance of Gillette area coals in utility power plants during this period. This paper covers some of the highlights of Exxon's experience with these coals in customer plants. I will focus specifically on things mining engineers may be able to do to make the product better for the customer's use.

Jan 1, 1989

By Michael E. Kelahan, Glenn A. Gruber

A review of recent phosphate beneficiation developments shows that Flotaire cells, ranging from 0.20 m to 2.44 m in diameter, have been examined in pilot scale and commercial plants. Applications of the column cells have included sized feed fractions using anionic and cationic reagent systems. In plants where the Flotaire was installed as a test unit or as an optional circuit, its use has been largely discontinued. On the other hand, when management committed to installing the Flotaire as an integral part of the flowsheet, the performance expectations were met or exceeded.

Jan 1, 1988

By Jorgen Elbrond

The economic environment of mining is particular and requires special methods for seeking the economic optimization of mining and guiding the construction of logical production planning systems. An interactive program system which generates sequences of mining rates and cutoff grades, using as it's core an open-ended dynamic programming algorithm, is described. The program system is built not with the aim of obtaining a single mathematical optimum, but on the concept of satisfying the mine planner by producing several alternative mine plans and testing various schedules under conditions of uncertainty.

Jan 1, 1982