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By A. W. Dickerson, G. Hollier, F. A. Bartley

Following on from many years of research aimed at improving the effectiveness of truck haulage operations in mines operated by BHP Minerals, BHP Research developed a concept for an Innovative Large Mining Truck, (ILMT) which has the potential to significantly improve the cost effectiveness of rear dump mining trucks. The ILMT concept reduces the empty vehicle weight dramatically, greatly reduces unequal rear tyre loading and improves ride and handling characteristics. The concept has been taken to the "proof of concept" prototype truck stage with the cooperative efforts of BHP Coal, BHP Research. Liebherr Mining Truck, Inc., Liebherr-Australia and Birrana Engineering. Testing of the prototype truck commenced at a coal mine in Queensland, Australia during May, 1996. Preliminary results from the testing program are very encouraging. Expectations are being met and in some cases exceeded.

Feb 24, 1997

The SFR system utilizes a skimmer or extractor placed at or near the slurry-froth interface where there is a higher concentration of valuable mineral particles. With assistance of hydrocyclones, it is possible to classify the extracted particles into coarse and fine particle streams, that can be handled separately. It also allows the coarser solids to be separated from entrained low-value fines. The first test results with the SFR system significantly improved both coarse and fine particle recovery in a flotation cell. The SFR system was tested in the flotation circuit at a copper-moly concentrator, and the results show that the use of the skimmer has huge potential to increase the froth recovery (Rf) of both molybdenum and copper.

Jan 1, 2012

NASA has received direction for lunar habitation beginning in 2024. Prior to then, it will be necessary to learn about how lunar soil can be used to promote civilization on the moon. Questions must be answered: ?Will it support plant life?,? ?Can it be used as a construction material?,? ?What is needed to maximize health and safety?,? and ?Will it affect equipment, tools, machinery, and clothes?? The only samples available for study came from the Apollo Missions. Because the expense of bringing more material back to Earth is prohibitive, there is not enough available to perform studies to answer the above questions. Hence, there is a great need for its synthesis. Most efforts to date have concentrated on making ?simulant? from single natural resources of volcanic rock. However, another possibility is to use resources here on Earth to extract the minerals of interest into concentrates or so-called ?separates? using traditional mineral processing techniques, and then mix the separates in appropriate ratios to simulate the lunar soil. In this paper, results from a study in which dry Road Norite outcrop and wet mill tailings from the Stillwater Mining Company?s Concentrator located near Nye, MT were examined. Of course, the in-side challenge is to make ?separates? from gangue minerals.

Jan 1, 2012

By Hongjie Yang

The No. 10 metro line of Shanghai city is 36 kilometers in length and will pass through the operating airport runway by using tunnel boring machine with earth pres-sure balance mode. Although there are examples through world that tunnels pass through airport runway and tunnelling underground is not a difficult undertaking technically, there is rare experience in China for the similar projects especially in Shanghai saturated soft soil region. Shanghai soft earth is famous for its high compressibility, high rate of water content, weakness in strength, large deformation and different characteristics in earth strata. Besides, the whole construction process will be under ultra-large airplane dynamic load on the surface ground over the tunnel, which increases the risks of construction process. This paper evaluates the feasibility of building the metro tunnel under such an extremely serious condition, especially the subsidence of ground surface caused by advancing of tunnel boring machine, which also is the most important control target for the safe operating of the runway. Furthermore, this paper discusses the effective measures to keep the settlements in the permissible level during the whole working period for the tunnel from aspects of plan, design and construction.

By Alfred Weiss

Selecting a minicomputer is not unlike selecting a costly piece of mining equipment such as a truck, shovel, crusher, or conveyor belt system. A marked difference might lie in the frequency at which such selection takes place; another difference might be mine management's familiarity with mining equipment vis a vis a minicomputer. These basic differences might prompt a mining company to seek the aid of a consultant when selecting a minicomputer system. Advantages and Disadvantages The fundamental advantage of employing an independent consultant is that it provides management with a source of knowledge and breadth of experience not readily available within the organization. If the consultant has a minerals background, such knowledge and experience are further enhanced by actual experience in exploration, mining, and mineral processing. If the consultant has worked within a mining company, such hands-on experience is supplemented with a meaningful understanding of the client's business; this facilitates communication between the consultant and members of the client organization. The consultant has been, so to speak, "in the client's shoes." There are several other advantages. Since computer systems cut across organizational boundaries, the independent consultant may be able to move within the organization more easily than an inside staff person to collect necessary information. Also, detachment from any manufacturer should provide the client with an objectivity and a set of recommendations as near optimal as feasible. The principal disadvantages lie in the area of continuity and accountability. Once the consultant's report has been submitted and his recommendations implemented, a discontinuity might occur. Also, if implementation does not provide the desired results, the consultant might not be available to correct the situation or account for actions taken. Proper selection of consultant services, relative to kind and duration, and the consultant's method of operation, will often prevent many of these aftereffects. Services Offered The professional consultant can help a client: •Define and summarize information systems technology* needs; • Evaluate alternatives such as in-house capability and capacity, time-sharing, or service bureaus; • Prepare a formal request for proposal (RFP) to be submitted to vendors; •Evaluate vendor proposals; •Evaluate the economics of lease vs. purchase; and •Assist in the conversion and installation. Thus, consulting services may range from evaluating an existing system and upgrading to a larger piece of equipment, to selecting a new first-for-the-organization computer. First, Define and Summarize Needs Regardless of circumstances, the most valuable document required before equipment selection is the information system plan (I/S plan). It helps insure that the company's information needs are met in a cost-effective manner. An I/S plan is usually a comporient of the mining company's overall business goals. Since an I/S plan is a formal vehicle for establishing and communicating the direction the organization intends to take to satisfy information requirements needed to achieve goals and objectives, most initial systems services are likely to center around creating such a document or updating an existing document. The trend toward company-wide I/S planning is increasing in the mining industry; however, smaller scale efforts focused at the information systems needs to support an individual

Jan 11, 1981

By J. H. Gasper

A cost analysis for two alternative contour mining methods is performed to compare their results. The methods evaluated are: 1) Front-End Loader/Truck Haulback and 2) Scraper Haulback. Before performing these analyses, output requirements and equipment needs are found based on integrating geometric limitations with material properties. The final geometric design establishes limits on clearances, congestion problems and grades (with associated running surface materials). All calculations are kept practical, with assumptions clearly stated. The cost analysis is a unique, easily utilized compilation of several different approaches incorporating cost engineering principles. The strengths of each are welded into a cohesive entity once again aimed at practical application. The results are presented in tabular form.

Jan 1, 1992

By S. Noll

Ventilation is an essential part of any underground mining operation. It provides fresh air for workers and machinery, keeps up an adequate mine climate and dilutes and dissipates noxious gases. Possible changes in the economic environment for mining in the future, e.g. increasing energy costs, will necessitate optimization of distribution of airflow within most mines. This paper discusses the scientific set-up for measurements as well as the behavior and influence of parameters of ventilation according to airflow distribution under consideration of technically possible set-ups of mine fans. This study was done in an underground mine with a flat seam room and pillar mining method.

Feb 27, 2013

By L. K. Marshall

The importance of high quality underground mine ventilation is readily apparent. The principles of primary and auxiliary mine ventilation, however, are sometimes less readily apparent. The first article in this two-part series discusses some general aspects of primary and auxiliary ventilation. Next month's article will detail considerations involved with auxiliary mine ventilation.

Jan 1, 1982

By William M. Gleason

When SME’s 2006 Arizona Conference convened in December at the Hilton El Conquistador Resort in Tucson, AZ, there was considerable excitement among the 387 attendees. There was a noticeable buzz surrounding the progress of Phelps Dodge’s Safford copper mine in southern Arizona, one of the first new major copper mines to be permitted in more than 30 years in the United States. There were also plenty of good feelings about the mining industry in general. Commodity prices remained high and with no signs of a slowdown in the immediate future. Things were good in Arizona. But there were also cautionary tones at the conference and the Mining Foundation of the Southwest banquet that preceded it.

Jan 1, 2007

By R. Y. Wan

Acid ferric sulfate solution has been used for heap and dump leaching of low-grade chalcopyrite ores and is being considered as a possible lixiviant for the hydrometallurgical processing of copper sulfide concentrates. For many years, researchers have attempted to explain the leaching behavior of chalcopyrite, since the reaction rate kinetics are extremely slow and seem to be significantly influenced by the nature of the reaction product. A summary of conclusions drawn from reported literature on chalcopyrite leaching is found in the paper by Munoz, Miller, and Wadsworth(1) and more recently by Dutrizac.(2) Lowe(3) and Jones and Peters (4) attributed rate control to a surface reaction. Linge,(5) Dutrizac,(6) Bauer,(7) and researchers at the University of Utah(1,8) reported that the reaction rate is limited by transport in the chalcopyrite lattice or through the elemental sulfur reaction product layer. Munoz et al.(1) presented a model, derived from the Wagner theory of oxidation, which is based on the formation of a protective sulfur layer with rate control by electron transport through the insulating sulfur layer. By utilizing Wagner's parabolic oxidation relationships, (9) the following equation was obtained: [ ] where a is the fraction of CuFeS2 reacted at time t, pB is the molar density of CuFeS2, do is the initial diameter of the particle, e is the electronic charge, s is the total electrical conductivity of the sulfur layer, and ?G is the Gibbs free energy for the reaction:

Jan 1, 1984

By M. S. Ellis, D. J. Nichols

In 1999, 1,100 million short tons of coal were produced in the United States, 38 percent from the Northern Rocky Mountains and Great Plains region. This coal has low ash content, and has sulfur content in compliance with Clean Air Act standards (U.S. Statutes at Large, 1990). The National Coal Resource Assessment for this region includes geologic, stratigraphic, palynologic, and geochemical studies and resource calculations for 18 major coal zones in the Powder River, Williston, Green River, Hanna, and Carbon Basins. Calculated resources are 660,000 million short tons. Results of the study are available in U.S. Geological Survey Professional Paper 1625-A (Fort Union Coal Assessment Team, 1999) and Open-File Report 99-376 (Flores and others, 1999) in CD-ROM format.

Jan 1, 2001

By John B. Spencer

Earlier this year, Simplot Phosphates achieved a safety milestone at its Vernal, UT phosphate operations. In March, the entire operation reached achieved seven years without a lost time accident. And the mine operations at Vernal reached the 1 million hours benchmark without a lost time accident. This million hour achievement has been 19 years in the making. This achievement reflects the mine’s strong attitude towards safety, the company said. Safety is an integral part of its culture and requires diligence and considerable work. Attention to even the smallest of details cannot be allowed to slip. This is a record Simplot Phosphates said it hopes to improve on every day.

Jan 1, 2004

By R. Dewey

WHAT IS AI? It's very hard to say. Most researchers and practitioners disagree with nearly any attempted definition, but most would agree that A1 does deal with the development of computer-related methods o f problem-solving. Artificial intelligence is a discipline which seeks to emulate human anatomy and/or thought processes by applying computer science, electronics, and mechanical engineering to the development of natural language processing, machine vision, robotics, and knowledge-based expert systems. Integration of these four fields will someday produce the robots of today's science fiction. A1 addresses problems of structuring large amounts of knowledge and representing relationships with rules and semantic frameworks rather than with mathematical equations. A1 is convergent rather than divergent - - conventional conputer applications use relatively small quantities of input to generate large output, but A1 generally reduces large amounts of information to establish a few major conclusions. The development of A1 has prompted greatly increased efforts on the part of scientists and engineers to understand just how humans think, organize information, approach problem-solving, and form conclusions. Some of the more exciting and possibly far-reaching advances in A1 are coming in this more-or-less soft-science area. Thirty years of A1 research (dating from a 1956 conference at Dartmouth College at which the term A1 was coined) has already spawned many widespread, almost ordinary, products: window graphics, hand-held controllers (mouse). function menus, etc., all in an attempt to make computers and people more compatible. WHAT IS AN ES? A1 can be used to develop EXPERT SYSTEMS, which are computer programs or systems which contain knowledge and rules by which problems can be solved. or at least by which possible solutions can be suggested for very complex problems. A1 can be used to better define problems so that solutions can be found. An ES is designed not to process numbers, but to process information according to rules and logic derived from actual practice and experience. WHY AI? WHY ES? Companies are increasingly aware of the value of accumulated knowledge and experience in designing, building, operating, and maintaining the increasingly complex or expensive physical plants in any business. As knowledge branches out and becomes more specialized, the accumulated learning of a veteran operator or manager or engineer becomes a scarce resource well worth preserving. EXPERT SYSTEMS offer a means of doing that, reinforcing, not replacing, human capabilities.

Jan 1, 1987

By Arnold Hammons

Automated temporary roof support (ATRS) systems have been incorporated into roof bolters since the 1970?s. During roof bolting, many injuries have occurred from large pieces of draw rock falling inby the ATRS beam and tipping back into the operator?s area. Other injuries have occurred due to smaller, sharp rocks falling onto the operator?s hand and arm during initiation of roof bolt drilling. These injuries are attributed to weak immediate roof, sometimes called roof skin failure. Even though ATRS systems support the roof and provide a measure of protection against roof skin failure, additional hazards sometimes do exist immediately inby and outby the supported roof. Design innovations such as the ATRS mounted rocker pad deflector systems have been designed to improve the roof bolter operator safety. This paper will inform the reader of the hazards, machine evolution through different design solutions, and the current state of the art in preventing roof skin failure injuries when roof bolting.

Jan 1, 2009

By Robert J. Rothwell

Underground mining of coal by longwall mining methods has not been a predominant technique in Ohio. To date, only five mines in the state utilize this method, however, the technique has sparked a certain amount of controversy. As a mining technique, longwalling was introduced into southeastern Ohio in the early 1970's but it did not attract public attention until the mines began moving into privately held surface lands. This occurred coincidentally at about the same time that the state of Ohio began to regulate the environmental impacts of underground mining. Prior to the passage of the Surface Mining Control and Reclamation Act in 1977, (SMCRA), Ohio's reclamation law, Chapter 1513 Ohio Revised Code (O.R.C. 1513) did not regulate underground coal mines. As a result of SMCRA, the Ohio Statute was amended in 1978, to include regulation of the surface effects of subsidence. The inevitable result was that existing mines were immediately subject to regulations that were not considered during the initial mine planning process. (For an excellent survey of Ohio Laws that deal with coal mine subsidence, see Zima, 1985. ) The problem faced at that time by both the coal industry and the Ohio Division of Reclamation (the agency within ODNR charged with implementing O.R.C. Ch. 1513.1, was that of attempting to superimpose permitting requirements, and design performance standards onto mines that' had been operational for a number of years.

Jan 1, 1986

By D. M. Muir

Thiosulfate offers a non-toxic alternative to cyanide for processing gold ores. The mechanism of leaching gold using ammoniacal thiosulfate solution is driven by the Cu(II)-Cu(I) redox couple and is complicated by competing ligands such as NH3 and S2O32-. It is shown that an understanding of the copper speciation and sulfur speciation is required to optimise this system. This paper presents Eh-pH and speciation diagrams for varying concentrations of Cu(II), S2O32- and NH3 and discusses the conditions under which various copper and sulfur species are stable.

Jan 1, 2001

By Amanda Elioff

Success of the Gold Line Eastside Extension rail tunnels in Los Angeles has prompted Metro?s planning for two new rail lines to include underground alternatives. The Westside Extension Transit Corridor alternatives include up to 17 miles of subway to be constructed in soft ground. The routes will require construction in Los Angeles? ?Potential Methane Zone,? not considered for subway construction until recently. Slurry face TBMs will likely be specified. The Regional Connector, through the downtown area, includes one underground alternative with 1.7 miles of tunnel as well as three underground stations in soft ground and rock. Challenges will include tunnel and station construction under narrow streets. This paper will describe the alternatives, planning, geologic conditions and tunneling concepts for both planning studies.

By J. H. Daniel, S. Krzemien

Partners In Economic Reform, Inc., established a Polish-American Mine Center in Katowice, Poland, in 1996 to improve working conditions in the minerals industry. The program was based on the experience of mining companies, government, and labor in the United States, and was executed by a Coordinating Committee headed by the Center Director and Polish leaders from industry, State, labor, and academia. The cooperation among all parties has enabled safety and health issues to become part of industry restructuring with impressive initial reductions in coal mine fatalities. Existing work practices and attitudes of labor and management were assessed in coal mines throughout the country. Promotion, Rules, and Job and Task Analysis were identified as the areas requiring the most improvement, and are part of a post-graduate Safety Management program. Demonstration projects included measuring dust levels, using safety glasses, and promoting hazard awareness. Improved labor-management relations increased cooperation allowing for effective transfer of technology. Results can also be applied to improve the working environment of the manufacturing sector also undergoing restructuring.

Jan 1, 2001

By J. Kuti

In room and pillar mining a large number of working points are arranged to follow a mining pattern. Geological and roof control problems can be overcome or their effect minimized by varying this pattern. Longwall mining on the other hand, fixes the mining pattern for anyone panel. This aspect of longwall mining leads to constancy, so that a well-conceived organization, ventilation, dust and roof control systems lead to daily repetition and subsequent simplicity of control. All the same, a fixed mining pattern calls for a very careful consideration and selection of design parameters. (Ref. 1.)

Jan 1, 1971

By Charles C. Dahl, Gordon C. Presley, Andrew E. Nevin, Bruce A. Kennedy

How does SME-AIME cope with profound changes in technology, markets - and most importantly - in employment patterns facing its membership today? This is the question that prompted the Society's Board of Directors to appoint a Long-Range Planning Commission (LRPC) (see ME, Feb. 1984, pp. 118 and 128). This is also the question addressed most particularly by the LRPC's Scope Committee. The Committee started its deliberations by asking such basic questions as "Who are we?" and "What is our business?" The Scope Committee then reviewed the findings and recommendations of other more specialized committees to develop and integrate their concepts of the Society's business for the next 10 years. The policy-making suggestions of the LRPC were reviewed and acted upon by the Board of Directors at its open meeting in Los Angeles on Feb. 26, 1984. At the Oct. 23-26, 1984 SME Fall Meeting in Denver, the Board will again review LRPC recommendations. In answer to the question "Who are we?" the Scope Committee proposed description, which was accepted by vote of the board of directors: . . A technical and professional organization that consists of individual members, namely those mining engineers, metallurgists, geologists, earth scientists, economists, managers, educators, and other professionals concerned with all facets of exploration, production, distribution, and using of mineral commodities. "These mineral commodities include all metals; industrial minerals, including construction materials and fertilizers; coal, oil shales, tar sands, and other mined fuels. Among the earth's mineral resources, only wellpumped oil and gas lie outside the Society's specific purview. "Traditionally, SME members work in the fields of engineering, technology, exploration and discovery, development, construction, mining, quarrying, beneficiation and processing, handling and transport, equipment manufacturing, sales and marketing, data processing, safety, land reclamation, environmental protection, taxation, administration, and management of these elements. "Members practice their professions in industry, in universities and research institutions, and in government. They may be operators, manufacturers, sales persons, contractors, consultants, analysts, researchers, educators, advisors, regulators, or members of supporting staffs. "The members of the Society are leaders in dedication to their crafts, in innovation, and in the pursuit of excellence. Among their numbers they count the most distinguished of engineers, applied scientists, and managers. "The Society is based in the United States, is active on a worldwide basis, and is open to nationals of any country. Certain qualifications must be met for attaining and maintaining membership." Purpose of the Society As to the question "What is our business?" the Scope Committee restated our purpose in light of current practice and the constitution of AIME and the bylaws of AIME and SME. The Board of Directors accepted the following proposed purpose of SME: "To further the professional development and well-being of its members by publishing and distributing technical writings, news, and information; by sponsoring meetings of members; by providing forums for discussions and for continuing education; and by fostering communication on the subjects within its purview. "The Society assists educa-

Jan 4, 1984