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By J. J. Fallon

Las Vegas is a place of many distractions. It is difficult for one to apply himself to sophisticated technical matters in the midst of gambling, liquor, scantily clad young ladies and the top entertainment available in the United States. But, I know that the men and women of SME are made of stronger stuff and will not be tempted by these things.

Jan 1, 1989

By H. Suharyono

A laboratory investigation of flocculation following polymer addition during slurry flow through pipes and in-line (static) mixers is described. Results are presented showing the effects of flow velocity, pipe length, in-line mixer elements and the use of multiple addition points on flocculation performance as measured by settling rate and supernatant turbidity. The effects of agitation and mixing time are shown to be generally consistent with the results of equivalent tests, both batch and continuous, conducted in stirred tanks.

Jan 1, 1995

By Darrell E. Young

This presentation will define what talc is, how it is mined and processed, and how talc is used in the paper industry. It will also give you some idea about who Luzenac America is and from where it came. Luzenac America was formed in July, 1992 as a result of the acquisition of the talc assets of Cyprus Minerals by RTZ of the United Kingdom. Cyprus Industrial Minerals was then merged with the other RTZ talc interests under the Luzenac name. Luzenac is a town in the Pyrenees of Southern France -and the home of Talc de Luzenac, RTZ's first talc acquisition. The Luzenac Group is the largest talc producer in the world.

Jan 1, 1993

By D. R. Dolinar, J. Pablic, D. C. Oyler, T. P. Mucho

At a mine in central PA, high horizontal stresses have caused long running roof falls resulting in hazardous conditions for the miners and the premature abandonment of panels. Because of these conditions, the mine requested assistance of the National Institute for Occupational Safety and Health (NIOSH) in utilizing the "advance and relieve" method to mitigate the affects of horizontal stress on the mine roof. "Advance and relieve" mining involves the removal of a pillar or a portion of a pillar during development, thereby creating a cave along one side of the panel. Following cave development, the horizontal stress is relieved over the workings adjacent to the cave in the active panel. The mine has used this system in three panels with a significant reduction in stress damage and no large roof falls.

Jan 1, 2001

By Lee W. Saperstein

The SME Research Council assists SME and its constituencies in establishing research directions that will benefit the mining industry and its professions. It also provides information about these directions to its membership, to government and to related industrial societies. The 1995 Research Forum, organized and chaired by George Luxbacher, was the second in a series of meetings organized to develop these directions. A copy of the full proceedings is available from SME for $12 plus postage and handling. The first research forum (Saperstein, L., 1993, "Technology for the Future, MINING ENGINEERING, Vol. 45, No 11, November, pp. 1382-85) invited mining industry representatives to discuss the unsolved technical problems that were keeping the industry from greater economic and environmental efficiency. The second forum asked academic researchers to discuss the same general topics from their perspective. It came as no surprise that, in general, the two sets of presenters tackled the same problems. There was no surprise when the academics spoke of the need for fundamental long-term research. What may have been surprising was the number of university people who spoke for near-term research that leads to measurable economic returns or savings. The closure of the US Bureau of Mines (USBM) has changed the objectives and attitudes of the SME Research Council. From being a point of liaison between SME and USBM - a conduit of items from each party to the other the council is now much more on its own. This isolation presents opportunities and hazards. The opportunities are exciting because the council could be the focus for mineral industry research policy if it were properly structured. The hazard is obvious - if there is no bureau, it could be argued, why maintain the council? Many people believe that SME should take the first course and become the beacon for research policy. More than ever, money is being spent on minerals industry research by the federal and state governments - particularly at the mineral-oriented land-grant universities - by industry and by consortia among these groups. SME could be at the hub of these programs. There is a general concern that industry is less able to maintain an economic edge by means of geologic discovery. According to Titley, there will be fewer major, new world-class discoveries except, possibly, at the continental and tectonic-plate margins. Consequently, economic advantage will go to those companies and nations that stay ahead technologically. Given the inevitable diffusion of technology, it can be concluded that technology development, underpinned by research, must be continuous to maintain profits. This is a change from earlier years when change would occur in relatively rare major steps that were interspersed with extended periods of technological equilibrium. Over the fiscal years 1994 to 1997, there has been a 24% cut in research spending by the Department of the Interior (figures from the American Association for the Advancement of Science). This is the largest budgeted percentage cut in research funding of any federal department. Even so, there is still a substantial amount of federal research funding expended in the mineral and extractive-energy industries. The US Geological Survey, Environmental Protection Agency, Departments of Defense and Energy and others expend substantial funds on minerals industry research. Industry - producers and manufacturers - is also spending large sums on research and research-like activities. This activity argues that there is a role for SME's Research Council. Providing focus Consortia. The closure of USBM has resulted in the migration of expertise to consulting firms and to other entreprenrutisl research entities. Many of these groups are creating ad hoc consortia among themselves, nearby universities and industrial partners. The Research Council is well placed to provide an open forum for these con¬sortia. Presentations of research results, as went on in the annual meetings of the Generic Mineral Technology Centers, can help to establish an. archive of results and an avoidance of duplication of research. A continuing sense of research directions can evolve. National Science Foundation. No discussion of consortia would be complete without mention. of the National Science Foundation's (NSF) programs for Industry/University Cooperative Research Centers (IUCRC) and Grant Opportunities for Academic Liaison with Industry (GOALI). NSF is aware of the gap in federal support of science and technology caused by USBM's closure.

Jan 1, 1997

By R. S. Kramer

A bulk compositional chemical analysis often provides incomplete information to help the mineral processor when faced with the problem of removing troublesome contaminants in low concentrations. Michigan Tech has developed a unique approach for addressing this problem. A combination of Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and image analysis was successfully used to characterize the species responsible for phosphorus contamination of less than . 05 weight percent in iron ore. An automated routine acquired the chemical signature of each particle on a back scattered electron image. The few particles containing phosphorus were identified from the hundreds of particles examined, and the phosphate phases present were easily characterized.

Jan 1, 1993

By W. Zitz

Incorporation of heat exchangers into drilled shaft foundations is a novel approach to both improve the energy efficiency of building heat pump systems and provide necessary structural support using the same construction materials. In an effort to quantify the structural and heat exchange performance of deep foundations used as ground-source heat pumps, two instrumented test foundations were constructed as part of a new construction project in Denver, CO. They will be integrated into the conventional ground-source heat pump system for the building. This paper focuses on the lessons learned from the construction process for these energy foundations.

Jan 1, 2011

By M. J. Friedel

The scale-dependent hydraulic properties in a fractured porphyry copper oxide deposit are investigated for relevance to In Situ Leach Mining (ISLM) design. In most well field designs, mine operators assume that hydraulic properties represent a continuous spatial function, or continuum. The problem, however, is that the representative elemental volume, the volume over which hydraulic properties are described as a continuum, is a domain (if it exists) that occurs between end members representing varying degrees of heterogeneity. At the Cyprus Casa Grande mine, transmissivity fluctuations are spatially correlated. This suggests that, at the scale of ISLM, the hydraulic process is heterogeneous, and a typical continuum representation is inappropriate for design. Alternatively, a conditional stochastic approach using the Simulated Annealing (SA) technique is deemed useful for the imaging of heterogeneous hydraulic properties. Specifically, SA preserves transmissivity extremes and spatial complexity, both necessary for accurate conditioning of a flow simulator. Also, the stochastic continuum approach provides an avenue whereby uncertainty (or risk) may be addressed. Currently, the SA weaknesses are that it is computationally time consuming and that uncertainty may increase when simulating under conditions of statistical isotropy. Recognizing that ISLM exerts a dynamic influence on hydraulic properties with time, the mine design should be re-evaluated at intervals throughout the evolution of the leaching process.

Jan 1, 1994

By W. J. Mahoney

A good quality assurance program at a coal mine or power plant is accurate, timely, and consistent. The quality analysis is accurate due to a complete sampling of the coal stream loaded into the unit train. The sample analysis is accurate because standardized testing procedures are applied. Once the analysis is completed, the results must be communicated to the electric utility in a timely manner. The electric utility needs the results to better manage the coal inventory at the power plants. A quality assurance program can also help the mine deliver a consistent product to the electric utility's power plants. The importance of the three major tenants for a good quality assurance program: accuracy, timeliness and consistency, are based on major changes that are taking place in the electric utility industry.

Jan 1, 1994

By H. W. Renner

The paper industry is an $80 billion/year business that is the largest consumer of industrial minerals. Paper industry generally refers to paper and paperboard products, including pulp mills. Grades and uses of paper and paperboard are very diverse, including such things as napkins, paper plates, corrugated boxes, magazines, newsprint, currency, and copier paper. Only about 40% of paper utilizes industrial minerals as fillers or coating materials. Minerals are used for both functional and economic reasons. Most often, minerals such as kaolin clay and calcium carbonate are used to improve print quality, brightness and opacity of paper. The minerals can be added as fillers into the paper in the wet end of the papermaking system, or can be applied as part of a coating to the paper. Coated papers are the highest quality paper, being used for magazines, advertising brochures and annual reports. Common uses for filled uncoated paper are books, copier paper, envelopes and many of the Sunday newspaper advertising inserts.

Jan 1, 1993

By C. Leal

Modern production has as goal to reach high and uniform quality in their products. To success with this, it is essential to have a good knowledge of the different variables involved in the process. Investigation or analysis of a process or system has as references the measurements of the variables. These measurements are presented normally in form of data. These data are measured in intervals over time. The aim with measurement of the data in a process is to obtain information about the state of it in order to have it under control. Other goal is to know how the results are affected by the process variables to improve upon product quality, redunding manufacturing cost, better pollution control etc.

Jan 1, 1994

By T. T. Gronfors

The excavation process and equipment used for excavation join firmly each other. By changing the process or method, the construction of equipment may be altered essentially. It has been possible to develop a wholy new type of hydraulic boom for tunnelling, when only parallel drilling instead of V-cut is used. The utilization of controlled blasting has made small holes more desirable. So the controlled blasting has had an influence on the selection of drill steel equipment and in this way also influenced the construction of the equipment.

Jan 1, 1970

By S. P. Mehrotra, P. C. Kapur

A phase-species classification is suggested for the mathematical models of flotation kinetics. Important models are discussed and the structure of their rate constants and parameters is analyzed. Split or enhancement factors are formulated for different kinetic models. The steady state dynamics of the flotation circuits can always be described in terms of these factors. For simulation of circuits, feed is characterized in a formal manner starting from a multivariate distribution of particles in flotation rate, size and mineral content. Synthesis of optimum circuits which simultaneously searches for the best process variables and structural parameters from a generalized master network is described. Trends in the areas of search algorithms, role of middlings and feed identification etc. are indicated.

Jan 1, 1989

Slurry technology developed for the marine transport of mineral commodities has been increasingly applied to on-shore slurry transport systems. Reclaim of mineral concentrates, sand tailings for mine backfill and various industrial minerals from storage tanks or ponds normally require a slurry of high density at constant flow rates to improve process performance and to reduce handling costs. An efficient system must accomplish this at minimum capital costs with maximum reliability. Continuing improvements in equipment design to improve repulping efficiency and their application are discussed.

Jan 1, 1986

By Im C. J.

The addition of coal preparation plants changed the coal industry during the past. Now it is time co once again improve the quality and types of coal products coming from future coal preparation plants to meet the changing needs of our society. Clean Coal Technology, along with federal support provided, is forcing our industry to provide cleaner coal products for industrial applications. Liquid fuels from coal is just one of many new products from a coal preparation plant that has a ready market in the transportation sector. UCC Research Corporation is developing these new liquid coal products and this paper will describe the progress and the new slate of coal products to be provided from future preparation plants.

Jan 1, 1989

By George K. Martin

This paper deals primarily with roof bolting in Kentucky coal mines from January 1, 1949, through December 31, 1954, a six year period. The Consolidation Coal Co? (Ky.), a division of the Pittsburgh Consolidation Coal Co., began systemmatic roof bolting in November 1948 in Mine #204, Elkhorn #3 Seam, at Jenkins, Kentucky, After the efficiency of roof bolting had been proven by the Consolidation Coal Co., this procedure was adopted by other companies throughout the state. In December 1954, approximately 46.4 percent of Kentucky's total production of coal from underground mines was obtained from roof-bolted areas. Statistics in this report will show the progress made in roof bolting during the six years, in addition to the roof bolting being done as of December 31, 1955. Significant progress has been made in the coal mines of Kentucky in reducing the roof-fall fatality, rates, during the past several years by adopting systemmatic roof bolting. The ground work by the Consolidation Coal Co, (Ky.) in cooperation with the Federal Bureau of Mines was based upon the previous experience of the St. Joseph Lead. Cc, in its Southeastern Missouri Mines and The Tennessee Coal and Iron Division of the United States Steel Corporation. The author gratefully acknowledges the cooperation and assistance given by officials of the various mining firms using roof bolts, the Kentucky Department of Mines and Minerals, and the Federal Bureau of Mines in furnishing photographs and information.

Jan 1, 1958

By L. L. Newman, K. D. Ferguson

Traditional methods for mine waste management produces two waste streams and the construction of separate disposal facilities. Tailings impoundment design is usually controlled by physical stability problems. Alternatively. the waste rock offers high stability characteristics but hydraulic properties that create ideal conditions for oxidation. The problem of oxidation is significantly reduced for tailings due to a fine texture that augments water saturation. This paper introduces concepts for the co-disposal of tailings with waste rock and evaluates the physical behaviour of an integrated waste system. 'he potential benefits of co-disposal are shown for a typical mine such as Equity Silver.

Jan 1, 2000

By A. Bruce Waugh, W. W. Wen, Kevin N. Clark, Neville C. Lockhart, Bruce A. Firth

Australia is the world's largest coal exporter, and technological advancement is a key element of the coal industry strategy. The issues include: increased recovery of saleable coal; enhanced quality, i.e. lower ash, moisture, fines, phosphorus (sulphur is a relatively minor problem for Australian coals); better quality control; higher throughputs/lower costs; improved handling and transport; and reduced environmental impacts. In process terms, many coal preparation operations, particularly fine coal circuits, are relatively inefficient, and all circuits must also be matched and integrated for optimum overall operation. A holistic approach to technological improvement is desirable. This paper summarises research and development efforts, within CSIRO and its collaborators, across the unit operations as outlined in the title.

Jan 1, 1995

By Mahmud Esad Uluer, Aaron Noble

Respirable coal mine dust (RCMD) is one of the biggest occupational health hazards for underground coal miners. Coal extraction is a main source of RCMD. To prevent challenges related to RCMD from developing, it is vitally important to limit airborne RCMD and stay within the regulatory limitations for mine operators. The flooded-bed dust scrubber (FBS), mounted on a continuous miner, is one of the most widely used dust mitigation technologies in room-and-pillar mining, but it is limited by technical challenges, the most notably being the potential to clog. In this study, the impact of mesh design and surface modification on system efficiency is examined using different vibrating, liquid-coated, stainlesssteel mesh panels in a laboratory-scale FBS.

Sep 1, 2024

By J. Keng, S. T. Chen, T. M. Shih

Kwanyin Tunnel is presently the longest (7.7 km) railway tunnel in Taiwan. Due to heavy railway traffic, a pass-by station will be built inside the tunnel to increase the traffic flow. Since the concentration of toxic gases released by the locomotives may reach dangerous levels, a research program was conducted for the purpose of designing a ventilation system which could dilute and/or remove the toxic gases to maintain an acceptable pollutant level. The program consisted of two parts. The first part was field measurement during which the concentrations of pollutants and wind velocities were measured at various points inside the tunnel to acquire basic data regarding ambient air quality, piston effects for the different types of trains, and existing ventilation conditions. Weather data (temperature, humidity, atmospheric pressure, wind direction and velocity) were gathered at many stations, both on the surface and inside the tunnel. The amount of pollutants released by each type of locomotive for various conditions were also measured. The second part of this study involved establishing mathematical models for predicting the air quality of the various proposed ventilation systems. Three different models were used for this work. The first one is a piston effect model which assumes that the gases and air undergo immediate mixing inside the tunnel. The second one is also a piston effect model which assumes that the diffusion ability of the gases is zero. The third one is a conventional ventilation model which was used for natural and mechanical ventilation conditions. From the result of field measurement and mathematical model studies, a ventilation system was chosen with consideration of both ventilation effects and construction costs.

Jan 1, 1987