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By Paul L. Hunter

Nearly 2000 people are employed at Kennecott's Chino Mines Division, which recently completed its 50th year as a leading copper producer. Chino operates an open pit mine at Santa Rita, N.M., and a reduction plant, including mill, power plant, and smelter, at Hurley, N.M. The property mines 66,000 tons of copper ore and materials per day. There have been safety and industrial health programs at Chino for a number of years, but in 1955 these procedures were reorganized on a more active basis. The following discussion evaluates the progress made during the 1955-1958 period.

Jan 6, 1960

By W. J. Taylor

The discussion on my paper entitled "Experiments with a Straight or No-bosh Furnace," read at the Philadelphia Meeting, September, 1884 (Transactions, vol. xiii., p. 489), suggests the propriety of slipplementing it with another, giving my views as to the cause of the failure, which was so decided as to create surprise among furnace men. As then stated, the Chester (8. J.) furnace, which had been 60 feet high, and 13 feet in diameter at the bosh, was altered to an 8-foot bosh, with a 7-foot hearth, 7-foot stock-line, and 4-foot bell,

Jan 1, 1886

Three meetings of the Institute for the presentation and discussion of technical papers were held in 1913: The 104th meeting, comprising the Annual Business Meeting as well as technical sessions, was held at New York, Feb. 18 to 20, 1913; the 105th meeting was held at Butte, Mont., Aug. 16 to 21, 1913, at which papers obtained largely through the efforts of the Committee on Precious and Base Metals were presented; and the 106th meeting was held at New York, Oct. 16 and 17, 1913, under the auspices of the Iron and Steel Committee.

Jan 1, 1917

By K. E. Brown, T. D. Murphy

At Monterey Coal's No. 1 Mine in central Illinois, it became necessary to predict if the sulfur content of individual trainloads of coal would exceed a contract sulfur maximum. Using geostatistics and Monte Carlo-type simulations, a forecasting procedure was developed to meet this need. The developed procedure predicts the monthly, mean sulfur content of the coal shipped and the probability of individual shipments exceeding the contract limit. During the first five months of using this procedure, the forecasted, monthly mean sulfur value was within 0.03% of actual. This represents a significant improvement over the inverse-distance, gridding-based, forecasting used previously.

Jan 1, 1994

The paper describes the $US240 million expansion at Hudson Bay Mining and Smelting Co LimitedÆs operations in Canada. The company has been continuously producing copper and zinc from local area mines at its Flin Flon metallurgical plant since 1930. The paper details the companyÆs operational turnaround since 1995 and æThe 777 ProjectÆ which includes: two new mines, expansion and modification of the concentrators, expansion of the zinc pressure leach plant, a new zinc electrolytic cellhouse and the modifications to the copper smelter gas handling system to reduce ground level gas emissions.

Jan 1, 2000

By David R. Holberg

In the Kansas City metropolitan area, mineable Bethany Falls Limestone occurs 80 ft below river level under the 700 acre Park College Campus on the north bank of the Missouri River at Parkville. For 20 years prior to this project various firms passed over this opportunity to mine this property for construction aggregate because of uncertain costs, financial risk, and the difficulty of constructing an entry tunnel. This paper describes the drill and blast construction, rock bolting, and shotcrete lining of a 750 ft. long, 15% declining grade, truck tunnel through several Pennsylvanian limestones and shales.

Jan 1, 1997

By James L. Vanderbeek

The Chino concentrator commenced operation in 1982 as a SAG-ball mill circuit which could process 37,500 stpd of ore. Since 1982, a series of process improvements such as the addition of two stages of SAG recycle crushing, allowed throughputs to increase to more than 48,000 stpd, at the expense of significantly coarser flotation feed sizing and reduced recovery. To compensate a third (tertiary) stage of grinding consisting of four 1250 hp Vertimills was installed which has allowed the flotation feed size and recovery to return to historical levels. The design and operational characteristics of the Tertiary Grinding Circuit are described.

Jan 1, 1998

By Daniel Hodouin, Claude Bazin, Sami Makni

Computer systems, installed in mineral processing, are designed to accumulate massive amounts of real-time data. Frequently these data are only partially processed because of the lack of adequate methods and the limited accuracy of mineral processing sensors. Methods are proposed to estimate missing data and reconciliate sensor data on a real-time basis. They are based on dynamic extension of steady-state techniques such as the node imbalance minimization or the least-squares mass balance adjustment techniques. The methods are illustrated for simulated and actual flotation data. Their data upgrading ability could be used to improve process monitoring, control and optimization.

Jan 1, 1993

By R. L. Grayson

As a followup to a USBM-sponsored research project, the authors utilized the knowledge-base structure and system concepts from a Sun Sparcstation-based worker-scheduling system of the mine-management support system to develop a PC-based application. The new software adopts the nested-window concept to facilitate data collection and modification on personnel, including their availability and work priorities during a shift. The system can optimally allocate manpower on a work shift and can delineate supervisory training responsibilities. The various components of the software, including enhancements made to the original system, are described in detail.

Jan 1, 1997

By M. M. Ragin, B. J. Scheiner

The US Bureau of Mines (USBM) has been investigating the use of polyethylene oxide (PEO) as a flocculant for a variety of mineral wastes. As part of this investigation, the hydrodynamics of the flocculation process were studied. It was determined that to obtain optimum dewatering results, the factors of energy input into the stirrer, polymer concentration, and polymer dosage must be considered. It was found that at a given polymer concentration, there were an optimum stirrer speed and polymer dosage. With excess PEO, the amount of water removed in the trommel decreased, but no evidence for steric stabilization was observed.

Jan 1, 1987

What has been billed as the underground drilling technology of the 1980's got a dramatic head start when Boliden engineers at Stekenjokk decided to go with all hydraulic drilling for primary ore production and mine development. This application represents a major first in meeting the needs of high productivity, better energy utilization, and an improved drilling environment. At Stekenjokk, engineers chose three Atlas Copco Boomer H132 two-boom electro-hydraulic drill rigs with the COP 1038 rock drills. An additional single-boom Boomer H131 was also selected with the COP 1038 HD for roof bolting functions.

Jan 12, 1977

By Kirk Conway, Richard L. Unger

The U. S. Bureau of Mines conducted a research project to analyze the design of underground mining equipment with respect to ease of maintenance and maintainer safety. The work included a review of maintainability design literature, an analysis of maintenance related accident data, field reviews of equipment designs, and interviews with mine maintenance personnel and equipment manufacturers. Based on the findings, a set of maintainability design recommendations have been prepared. The final recommendations document includes maintainability engineering information for equipment designers, as well as a buyers' guide to aid purchasers of mining machinery in evaluating the maintainability of equipment.

Jan 1, 1992

By F. Kennedy

Consolidation Coal Co. (Consol) supports an active research and development effort to improve the safe, productive mining of coal and to use coal in an environmentally acceptable manner: Attention will be focused on degasification of coal seams, continuous coal transport systems, earth sciences activities, and coal combustion. Brief mention will be made regarding the SO2 emissions control programs. The research program constitutes about 1 % of Consol coal sales, which positions Consol as the preeminent coal company supporting broad-based research addressing the full spectrum of the various problems associated with using the nation's abundant reserves of economical, readily available fuel.

Jan 1, 1990

By S. O. Yuan, R. L. Grayson

As a followup to a USBM-sponsored research project, the authors utilized the knowledge-base structure and system concepts from a Sun Sparcstation-based worker-scheduling system of the mine-management support system to develop a PC-based application. The new software adopts the nested-window concept to facilitate data collection and modification on personnel, including their availability and work priorities during a shift. The system can optimally allocate manpower on a work shift and can delineate supervisory training responsibilities. The various components of the software, including enhancements made to the original system, are described in detail.

Jan 1, 1998

By M. M. Singh

Coal mine operators are obligated to mitigate or plan for subsidence under the new regulations. This paper presents the types of subsidence control measures that may be employed to meet these requirements, which include: changes in mining methods, strata stabilization after coal extraction, construction of specially designed surface structures and foundations to accommodate ground movements, and comprehensive planning and coordination of surface land use with underground mining. The basic principles of these techniques, along with specific procedures that may be followed to implement them, are briefly discussed. Subsidence control methods that are currently being investigated are mentioned.

Jan 1, 1985

By J. C. Yingling, R. Kumar, J. Sottile

The capability for on-line measurement of the quality characteristics of conveyed coal now enables mine operators to take advantage of the inherent heterogeneity of those streams and split them into wash and no-wash stocks. Relative to processing the entire stream, this reduces the amount of coal that must be washed at the mine and, thereby reducing processing costs, recovery losses and refuse-genera¬tion levels. In this paper, new ap¬proaches for optimal control of the segregation process using time-se¬ries models and empirical distribu¬tions are presented and demon¬strated using field data.

Jan 1, 2000

By Durao F

A multi-layer feed-forward neural network was trained (using the error back-propagation algorithm) to learn a subset of rules designed to stabilise the performances of the copper flotation section of a complex sulphide processing plant and then tested in order to evaluate its expert performances. Two types of neural networks were compared: the classical ones, fully connected between one layer and the adjacents (with different architectures), and entropy networks, partially connected and generated according to a methodology that simplifies its building up. The advantages and drawbacks of both were analysed and compared with classic (rule based) expert systems.

Jan 1, 1995

By J. R. Caylor

The Mine Safety and Health Administration (MSHA) advanced several initiatives last year to further protect miners' health. Regulatory efforts included the implementation of a Hazard Communication rule for all mines, work on the Single Sample rule for all coal mines, and the Plan Verification rule for underground coalmines. Development and application of new technologies are actively encouraged in preventing miners' hearing loss and respirable dust overexposures. MSHA's successful x-ray program for screening of black lung among coal miners completed its third year. Compliance Assistance efforts are focused on Best Practices, outreach, and technical support for operators' specific challenges.

Jan 1, 2003

By David A. Milligan

This paper outlines the research and development of a process to treat flotation tailings from the Darwin mill in lnyo County, California. A flowsheet was developed incorporating an agglomerated heap leach process using sodium cyanide to extract the silver values. Agglomeration was the key to developing this resource as the mill tailings averaged only 13% plus 100 mesh. Percolation through the heap would have been impossible without agglomeration to improve the permeability. The various tests that went into this research program are described with particular emphasis on the agglomeration techniques developed at the Anaconda Minerals Research Center. Start up and operation are discussed.

Jan 1, 1984

By W. E. Anable

A 180° magnetic deflection residual gas analyzer mass spectrometer with a mass range of 2 to 200 amu was used to study the nature of gases evolved during arc and electron-beam melting of certain reactive and refractory metals. The partial pressure of residual gases over molten Mo, Hf, Ti, and Fe, was found to be similar: Water and hydrogen were evolved from the samples and from the furnace components, carbon dioxide and carbon monoxide resulted from deoxidation of some of the melts. Argon and acetone were residuals in the system, and methane was a decomposed organic compound from the oil diffusion pump.

Jan 1, 1969