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By Davies C. E

At present the source of virgin iron for steel produced in New Zealand is titanomagne- tite extracted from titaniferous beachsands. Some of these beachsand deposits contain extractable quantities of ilmenite as well as titanomagnetite and both minerals represent challenging sources of vanadium and titanium products in addition to iron. This study looks at some theoretical aspects of smelting these ores directly with coal rather than with electric power, and takes into consideration the properties of the raw materials, the thermodynamics of possible process routes and the background of the economics involved.

Jan 1, 1980

By T. E. Green

The Bureau of Mines Heavy Metals Program emphasizes the need for improved analytical methods for gold determination. A commercially available ion exchange resin with high selectivity for gold was investigated as a potential method to collect gold from solution. The resin was found to quantitatively collect gold from acid solutions over a wide range of acid concentrations. Common metals were not collected by the resin nor did they seriously interfere with the collection of gold. X-ray spectrographic and neutron activation methods based on the use of papers containing this resin are proposed.

Jan 1, 1970

By K. H. Nimerick, G. P. Laflin

Laboratory data and field tests indicate that substantial losses of valuable coal can be caused by wind erosion. Wind tunnel tests show the effects of wind velocity and particle sizing on the amount of coal lost while in transit. Different coals were evaluated to determine the variables associated with wind erosion. The erosion losses can be substantially reduced by using a binder, or crusting agent, to consolidate the surfaces of the coal into a solid mass which resists erosion. This not only reduces economic loss but minimizes polllution.

Jan 1, 1980

By K. A. Natarajan, I. Iwasaki

Electrochemical measurements were made wing chalcopyrite and pyrrhotite electrodes in aqueous solution containing a xanthute collector and ground ore mineral particles. The purpose was to investigate the electrochemical reactivity of ozone with respect to dissolved xanthute, surface adsorbed xanthute, and the sulfide mineral itself. Electro-chemical evidence for the removal of xanthate coatings from chulcopyrite, pyrrhotite, and platinum surfaces by ozone is presented. The oxidizing power of ozone is compared with that of oxygen and other common oxidizing agents to portray the superiority of ozone as an oxidant.

Jan 1, 1986

By King R. L

The Bureau of Mines has developed and deployed three expert systems to give advice on mining health and safety. These are: dust control for continuous miners, dust control for longwall shearers, and methane control. All three systems query about the nature and extent of the problem. Typical questions asked deal with observed methane levels, ventilation type and quantity, cutting sequence, and what control technology is employed. Advice given does not focus on a single issue, but may suggest a variety of approaches consistent with the ability of the operator to implement the Suggestions.

Jan 1, 1988

By Paul Grisley

Air-supported belt conveyors-conveying systems that replace troughing idlers with a film of air-were a revolutionary concept when introduced in the 1970s. But high installation and operating costs limited their application. Now, system refinements have led to successful applications, even under the challenging conditions of mines and process plants. In this presentation the author will discuss the latest developments in the engineering of these systems, including the ability to retrofit existing transfer points with modular air conveyor components. Air conveyor applications and limitations in mineral-handling operations will also be examined.

Jan 1, 2002

By Weldon B. Smith

When faced with excavating vast amounts of overburden at its surface coal mining operation in Centralia, Wash., the Washington Irrigation and Development Co. (Widco) chose to utilize a bucket wheel excavator and shiftable conveyor system. In the early 1970s, Widco-a subsidiary of the Washington Water Power Co.-held reserves of sub-bituminous C coal estimated at some 180 million tons (200 million st). Subsequent investigation of the overlying land formations revealed the need to excavate millions of bank cubic yards of material as part of the mining plans.

Jan 7, 1979

By E. L. Brack

ASARCO's copper smelter at Hayden, Arizona has been upgraded to meet the increasing Environmental Protection Agency (EPA) and Occupational Safety and Health Administration (OSHA) environmental standards. Fortunately, means were found to accomplish these standards and provide for more efficient operations. With the adaptation of oxygen flash smelting and other related operations at Hayden, ASARCO has turned to the use of minicomputers and microprocessors for inter-plant communications and local area process control. The applications of distributive and computer controls to the plant operations at the Hayden smelter are discussed in this paper.

Jan 1, 1984

By L. B. Rothfeld

Two new coal use technologies are on the verge of commercial acceptance by the utility industry: atmospheric fluidized bed combustion (AFBC) and gasification combined cycle (GCC). Generating plants under construction or in planning will replace older pulverized coal (PC) boilers or substitute for new PC boiler capacity. This paper reports recent developments in the commercialization of AFBC and GCC, emphasizing the potential impact on the coal mining industry. The influence of coal quality characteristics on fuel selection is explored by means of preliminary economic calculations for different coals and competing fuels.

Jan 1, 1987

By W. C. Meyer, R. R. Klimpel

A physical model of flotation, derived from viewing froth as a kinetic species since it constitutes the carrier of ore particles, not only agrees with and is simulated by engineering mathematical models, but is statistically verified by actual laboratory flotation data. The model couples the mechanical removal of froth using paddles with the more rapid interactions taking place in the bath. It clearly shows that the kinetics of mass removal is dictated by flotation cell dimensions, paddle speed, and, more importantly, froth characteristics. Some conclusions and model predictions are presented.

Jan 1, 1984

By Lei Chen, Michael L. Free, Ravindra Bhide

The incorporation of particles into metal matrix materials is important to many technologically important areas. Particles that are incorporated into a metal matrix have a significant effect upon the properties of the resulting composite. Proper selection of particles and incorporation densities can lead to optimal composite properties that can be modified as needed for various applications. This paper discusses the parameters that affect the particle incorporation density in electrodeposited metal matrix composite coatings as well as a deterministic model that can be used to predict the effects of such parameters on particle incorporation density.

Jan 1, 2003

By G. Ríos

Atlantic Copper Metallurgical Complex in Huelva (Spain) was commissioned in 1970 with a capacity of 40,000 tpy of copper from concentrate. In 1975 the old blast furnaces were replaced by the Outokumpu FSF technology. During the last 30 years, through several expansions and technical modifications, the production has increased up to 300,000 tpy of new copper. This paper describes the developments on the control of impurities that have been made to fit new situations, such as a new artificial gypsum plant, a new electrolyte treatment plant or different secondary materials handling management.

Jan 1, 2006

By Lama RD

The paper outlines the development in the control of dust in Australia over the last 20 years. Factors influencing dust make at the faces are discussed. The effect of high production systems is analysed. Changes in dust standards and results of dust sampling on longwalls and continuous miner panels are given. Research conducted on air curtains and water infusion on dust control on longwall faces is presented along with recommendations for future research. It is found that both dust curtains and water infusion can cut dust mak by 50" each when applied separately.

Jan 1, 1988

Accurate modeling of the semivariogram is an extremely important step in the geostatistical analysis of mineral deposits. Automatic fitting of a mathematical model is often possible but not necessarily desirable. Significant geologic and statistical information must be taken into account in the fitting process, which is not always available to the computer. Manual model fitting is, on the other hand, extremely time consuming. Interactive graphics are best suited to optimize the process. Many interactive methods are described, which are adapted to modeling semivariogram in one-, two-, or three- dimensional environments.

Jan 1, 1985

By Iwao Iwasaki

Since the oil crises in the 1970s, the mining industry in the developed countries has faced strong competition from developing countries. In order for the North American iron ore industry to remain competitive with high-grade overseas sources, research on low-cost beneficiation methods that ensure high-quality and uniform-quality products must be maintained in order to prepare for ever-tightening specifications on iron making raw materials for blast furnaces and also for the future iron- and steelmaking processes that can directly utilize finely ground concentrates.

Jan 1, 1999

By Howland Bancroft

The writer has observed that some confusion is experienced by many mining engineers in making vertical sections of ore deposits in mining properties which they have examined. Having much examination work calling for the correct interpretation of vein structure and the subsequent platting of the same on sections, it has occurred to the writer that the accompanying diagram may be of use to others who at times may be called upon to prepare numerous sections. For example, a great mass of data on strike and dip of ore bodies is collected underground in separate

Jan 1, 1915

By Gustave E. Behr

The peculiar and changing conditions of a wartime market and the necessary governmental restrictions have resulted in an accumulation of a large amount of certain secondary metals in the tin-lead alloy class. With certain of these metals this accumulation has reached such proportions that it has been proposed that government agencies finance the creation of stockpiles of these secondaries just as stockpiles of primary metals have been created. The purpose of such financing would be to keep the secondary metal dealers engaged in collecting these metals, which they might

Jan 1, 1943

By James R. Walpole

This paper will discuss the federal laws and regulations that are related to water quality. Both surface and underground water quality issues will be covered as well as point and nonpoint source requirements. Some of the subjects to be covered include the Federal Water Pollution Control Act (e.g., effluent guidelines, nonpoint source requirements, etc.), the Safe Drinking Water Act (e.g., underground injection control requirements; pits, ponds, and lagoons study, etc.), the Resource Conservation and Recovery Act (e.g., mining wastes study, etc.). The importance of related court decisions will also be discussed

Jan 1, 1982

By A. D. S. Gillies

The effectiveness of coal mine face ventilation and the ability of airflow to maintain satisfactory methane and respirable dust levels in the working face area has been studied through the use of scale modeling techniques and underground testing procedures. In particular, consideration has been given to examination of the effects of operation of a high airflow, machine mounted dust scrubber unit on face air patterns. Results obtained through a cooperative study with the Peabody Coal Co. demonstrate that new mining cycles can be considered that increase production efficiency while maintaining satisfactory ventilation conditions.

Jan 1, 1986

By Bob de Raadt

For a long time industrial underwater blasting has stood in need of a calculation method, for the determination of shockwave-proof as well as shockwave-effective charge distances to objects in water. After a brief discussion of the physical background of the shockwave mechanism in water, the author discusses an empirical theoretical computing method based on the "Bubble boundary" concept. The practical application of this model is finally shown in an account of a few underwater blasting operations in which charge weights of c.1-1000 kg were involved.

Jan 1, 1980