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By R. H. Church

The Bureau of Mines' Tuscaloosa Research Center has developed a field test unit (FTU) which dewaters mine and/or mineral processing by-product slurries. The feed material (by-product slurry) is mixed with a known quantity and specific type of synthetic polymer (usually a polyacrylamide) to induce flocculation in a continuous operation. The flocculated material passes over a specific number and size of slotted stationary screens which separates the flocculated solid material from the "clean" water. The "static screens" are positioned at a fixed angle to maximize flow capacity and capture of the solids content. An investigation was conducted at an industrial crushed stone operation located near Birmingham, AL, to determine if the Bureau's FTU could successfully dewater the waste slurry generated during grinding and sizing operations at this facility. The investigation showed that waste slurries could be dewatered to 50 pct solids, at a polymer cost of approximately $0.85/ton of dry solids treated, and resulted in approximately 85 to 95 pct solids recovery. The dewatered material continued to consolidate and reached 69 pct solids in 24 h. Presently, the waste slurry generated at this facility is discarded into impoundments. However, this research has identified the recovered waste as an economically marketable product.

Jan 1, 1994

By Rollien R. Wells

The Bureau of Mines was created in 1910 by an act of Congress and subsequently directed to: "...conduct inquiries and scientific and technologic investigations concerning mining, and the preparation, treatment, and utilization of mineral substances with a view to improving health conditions, and increasing safety, efficiency, economic development, and conserving resources through the prevention of waste ..." Under this broad charter, the Bureau's responsibilities have changed and grown from an almost exclusive concern with coal and coal mine safety to the present emphasis on a full spectrum of mineral producing and consuming problems. In the past 30 years, the domestic consumption of coal, oil, gas, metals, and industrial minerals has more than quadrupled, in parallel with the rapid and enormous growth in industrial production. Of the scores of metals and nonmetals essential to the Nation's progress and security, many are scarce and difficult to wrest from domestic sources. Reserves of some ores are dwindling. Available ore resources are becoming leaner and more difficult to treat. In recognition of this many faceted problem, the Bureau has engaged in a continuing quest for new and improved technology to enable economic exploitation of marginal minerals and fuels, to find substitutes for minerals in short supply, and to create better materials to meet the expanding and diverse requirements of the growing economy. The current central concern of the Bureau is focused on meeting projected fuel, metal, and mineral demands at the lowest real cost by recovery from available resources by new and improved technology that minimizes waste, hazards, and social and environmental problems.

Jan 1, 1970

By James J. Olson

Most of the projects summarized in this paper are funded under the Bureau's Advancing Metal-Nonmetal Mining Technology program and are part of the in situ mining subprogram coordinated at the Twin Cities Mining Research Center. The borehole mining equipment development, are funded under the Bureau's Advancing Coal Mining Technology program, is essential to accelerated progress in the in situ mining subprogram, and some background information on this concept is included. The initial in situ research projects started in 1971-72 evaluated some of the critical blast design parameters for in situ copper leaching. The present program totals about $1 million per year and includes in-house research projects, cooperative (cost-sharing) projects with the mining industry, and research and development contracts. Two different extraction schemes are under investigation: inplace leaching and borehole (or slurry) mining. The principal commodity targets for the Bureau's improved in situ mining technologies include copper, uranium, coal, and potash. The principal purpose of this paper is to inform the mining industry of the in situ mining research recently completed or being conducted by the Bureau of Mines. In addition the Bureau encourages companies to comment on the program accomplishments as well as offer suggestions on top priority research needs for improving the in situ mining methods described in this paper.

Jan 1, 1977

By Daryl R. Tweeton

Bureau of Mines research in in situ uranium leaching includes injection well construction and environmental aspects. Clogging of injection wells is a common problem, and is affected by construction techniques. Part of the clogging can be caused by a low-permeability skin left on the borehole wall if the drilling fluids are not thoroughly flushed out. Certain polymer drilling fluids are less prone to cause clogging than bentonite muds, since a lower solids content can be used. The environmental research primarily involves two contracts. The first describes the environmental impact of in situ leaching and the effect of environmental legislation on leaching; the second describes the cost effectiveness of various methods of restoring ground water quality.

Jan 1, 1978

By James J. Snodgrass, David E. Siskind

The Bureau of Mines investigated the effects of vibrations from underground blasting in four rock types to define blast parameters that affect vibration amplitudes and to establish means of predicting expected vibration levels. Previous studies of surface blasting indicated that charge weight per delay period had a major influence on vibration amplitudes. Dividing the distance from the blast by the square root of the charge weight scaled the effect of various charge weights, however, and allowed vibration data for a particular site to be represented by a propagation equation of the form v = K(D/W ½ )-n (1) where v = particle velocity, D = distance from the blast, W = maximum charge weight per delay period, and K and n = empirically determined site constants. For square-root scaling, particle velocity and acceleration data from the underground sites appear to follow a similar propagation law. The subsurface data are in good agreement with those of the surface studies and provide a basis for engineering estimates of vibration amplitudes in many different rock types.

Jan 1, 1974

By George H. Schnakenberg

The application of automation and robotic technologies to coal mining equipment at the face offers improvements in worker safety and efficiency. The evolutionary introduction of autonomous, intelligent machines to perform the most hazardous tasks in underground coal mines may become a reality within the next 10 to 15 years. The US Bureau of Mines Advanced Mining Systems research program is developing the technology necessary to achieve this goal. This program consists of both core and applications re¬search that focus on the fundamental issues of sensor-based, computer-assisted, machine control technology. In the near term, the research is directed specifically to the computer-assisted control of present-day underground equipment. The immediate effect will be relocating equipment operators to a nearby area of safety. It is being performed in a manner that can make incremental improvements in safety and efficiency. The research is being performed closely with private, government and academic researchers in the miring, space, armed forces and factory automation and robotics research areas. It is a mixture of basic research, applied research and the application and adaptation of existing technologies from a multitude of sources.

Jan 1, 1990

By Lawrence L. Davis

This paper describes current research by the Bureau of Mines to develop technology for improving efficiency and productivity in metal/ nonmetal mines. The research program addresses a wide variety of problems associated with each of the major categories of mining: underground mining, surface mining, in situ mining, and premining investigations. An overview of the Bureau's research activities is given with emphasis on underground mining. In particular, two innovative and promising concepts currently under development are described: a unique shaft sinking system that uses an impact hammer for rock fragmentation, and a low-profile, portable crusher for underground hard-rock applications.

Jan 1, 1979

By R. J. Morrell

The Bureau of Mines, U.S. Department of the Interior, has developed a hardrock cutting concept and incorporated it into an extraction system called the ripper miner. This concept uses a single, wide bit that attacks the rock at a shallow angle and slow speed. Research has demonstrated that the system is capable of excavation rates exceeding those possible with conventional drill-blast and can effectively cut rock too hard for conventional roadheaders or continuous mining machines. It has the additional advantages of low bit wear and dust generation. This highly flexible concept is applicable to both mining and driving development openings and can cut any material from coal to hard rock. A single rip-per miner can perform the functions of a continuous mining machine, a roadheader excavator, and a tunnel boring machine. This paper presents the history of the development of the ripper miner from the initial laboratory tests through the construction and testing of the full-scale, lab prototype. It includes a comparison of the ripper miner to systems currently used from the standpoint of energy efficiencies and operating costs.

Jan 1, 1989

By P. A. Hendricks

The surface coal mining industry in the United States employs over 50,000 people and is responsible for 60% of domestic coal production. This represents a very significant contribution to our national economy and an important source of highly skilled and well paying jobs. The U.S. Bureau of Mines (USBM) has targeted surface mining as an important research priority to reduce the social and economic costs associated with surface mining injuries and fatalities. USBM safety research focuses on the development of technologies that can enhance productivity and reduce mining costs through a reduction in the number and severity of mining accidents. This report summarizes a number of completed and ongoing research programs that address a broad range of surface mining safety problems. Research methods are described, and research products which are suitable for industry implementation are highlighted.

Jan 1, 1994

By John A. Breslin

Control of radiation hazards in mines is only one of many goals of the Bureau of Mines. Radiation research is only a small part of the Bureau's mine health and safety research program. In this paper I will describe the mission and programs of the entire Bureau of Mines, with emphasis on the mine health and safety program of which our radiation research is a part. The radiation program and its results will be described in detail by other speakers during this symposium. The Bureau of Mines was established in 1910 and is one of a number of agencies within the Department of Interior. Our mission is given by the Organic Act of the Bureau of Mines, last revised in 1913, which still accurately describes our work today. The amended Organic Act (Public Law 62-386) gives the Bureau authority "... to conduct inquiries and scientific and technologic investigations concerning mining, and the preparation, treatment, and utilization of mineral substances with a view to improving health conditions, and increasing safety, efficiency, economic development, and conserving resources through the prevention of waste in the mining, quarrying, metallurgical, and other mineral industries; to inquire into the economic conditions affecting these industries..." Since 1913 at least 52 public laws bearing on Bureau responsibilities have come into force. However, our basic role is still unchanged, i.e. improving health conditions, and increasing safety and efficiency in the mineral industries. The two principal activities of the Bureau are Minerals Information and Analysis and Minerals Research. The Minerals Information and Analysis programs provide the data base and the analytical capability to support the development of effective national mineral policies. Data on the availability, production, and utilization of minerals are collected, interpreted, and analyzed for some 100 commodities. Resources of the most important commodities are evaluated to support policymaking that influences utilization of the Nation's existing and potential mineral supplies. The President's budget for the Mineral Information and Analysis programs in fiscal year 1982 is $34 million. The largest activity of the Bureau is Minerals Research, which is divided into three major programs: Mineral Resources Technology, Minerals Environmental Technology, and Minerals Health and Safety Technology. The principal goal of the Mineral Resources Technology program is to help provide technology to maintain an adequate supply of minerals for the United States. The budget requested by the President for this program in fiscal year 1982 is $41 million. The goal of the Minerals Environmental Technology Program is to create mining and mineral processing operations that are more compatible with the environment. The budget for this program in fiscal year 1982 is $12 million. The largest program of the Bureau is Minerals Health and Safety Technology, which has the goal of providing the technology to protect the health and safety of mine workers. The budget for health and safety research for fiscal year 1982 is $55 million. Our radiation research is part of the health and safety research program. The Bureau of Mines has done research to improve health and safety conditions in mines since it was established in 1910. The research expanded greatly following the passage of the Federal Coal Mine Health and Safety Act of 1969 (Public Law 91-173) and the Federal Mine Safety and Health Amendments Act of 1977 (Public Law 95-164). These acts provided for increased health and safety regulatory activities, but they also significantly increased the funding available for mine health and safety research by the Bureau of Mines. Funding for the Bureau's health and safety research grew from $12 million in 1970 to $60 million in 1981. The funding in 1982 will be somewhat lower than that for 1981. However, the health and safety program funding is still approximately 40 percent of the total budget of the Bureau of Mines. Of the health and safety budget, 22 percent is spent on research to control health hazards in mines, including radiation hazards, which has a budget in 1982 of approximately $1.1 million. Other mine health hazards which the Bureau is doing research to control include respirable mine dusts which cause black lung and silicosis; excessive noise; toxic gases from explosives and diesel emissions; and excessive heat in deep hot mines. The other 78 percent of the budget is spent on safety research to prevent death and injury to miners from such causes as roof falls, fires, explosions, and accidents involving mining equipment. Over the past decade the majority of the Bureau's health and safety research has been done through outside contracts with private industry and universities. Our policy has been to do some research inhouse to maintain the expertise of Bureau personnel. Contractors are used to do research for which the Bureau does not have the necessary personnel available. The percentage of the program being done by contract has been gradually declining for the past few years, and in 1982 the program will be divided evenly between inhouse and contract research. The inhouse research of the Bureau is done at the 10 research centers located throughout the country. Our radiation research is done at three research centers, Denver, Spokane and Pittsburgh, and by contractors whose work is monitored by project officers at these centers. There are three Federal agencies involved in mine health and safety. These are the Bureau of Mines, the Mine Safety and Health Administration (MSHA), and the National Institute for Occupational Safety and

Jan 1, 1981

By B. P. Bellport

This paper summarizes the Bureau of Reclamation's experience in the use of boring machines to excavate six major tunnels on the Bureau's water resources development projects in the western United States. The summary of experience is presented as a compilation of brief case studies for each of the six tunnels. Each compilation presents data on the tunnel dimensions, geological characteristics of the excavated rock, the tunneling machine used, machine operation, muck handling, method of tunnel support, ventilation system, and related information. The listing of the six tunnels in Table 1 reflects a diversity of tunnel lengths and diameters. However, despite this diversity of dimensions as well as the variety of rock encountered during excavation, the six tunnels have one major characteristic in common: their excavation was significantly expedited by the use of boring machines. Beginning with the 10,079-foot-long Tunnel No. 1 on the Navajo Indian Irrigation Project in New Mexico - the Bureau's first tunnel to be excavated by a boring machine - the boring machines, or "moles," have demonstrated their effectiveness in rapid and economical tunnel excavation. Tunnel No. 1, virtually 2 miles long, was bored through in 9 months, an unprecedented achievement in Bureau engineering experience, as compared with tunnels previously excavated by conventional means. Boring of the 45,630-foot-long Blanco Tunnel and the 26,610-foot-long Oso Tunnel, both on the San Juan-Chama Project in Colorado, set world records in rates of excavation,l/* Two days of exceptional progress highlighted the

Jan 1, 1970

By Lee W. Saperstein

In surface mining for coal, common practice for the disposal of preparation plant refuse is to bury it. As with surface refuse piles, these buried wastes can ignite and can also lead to ground and surface water pollution. Steps to ameliorate these problems have been devised over the years. C and K Coal Company, of Clarion, Pa., the largest Pennsylvania surface mining company, has incorporated all of these steps and added of few, of their own in their latest disposal practice. In addition to layering and compacting, C and K practices selective placement and dilution to minimize longterm problems.

Jan 1, 1977

By Michael M. Donahue

"The public interest -- as opposed to the narrow interests of particular shippers -- will also benefit from the establishment of adequate revenue levels and the revitalization of the railroads. And this is particularly true with respect to the transportation of coal. "

Jan 1, 1981

By Jurgen H. Kleinau

This paper details Keeler/ Dorr-Oliver's experience with the application of fluid bed combustion technology to the burning of coal-mining waste. The designs of two stage fluid bed combustors/dryers are demonstrated as useful in the drying of coal, slag and coke, using coal and coal refuse (gob) as fuel. Anthracite mining refuse (culm) is more than abundant in Northeastern Pennsylvania. After demonstration at Shamokin, Pennsylvania, a full commercial-sized fluid bed boiler using culm is used for district heating in Wilkes-Barre, Pennsylvania. Limited research work has shown the utility of using fine coal as filter aid in sludge in¬cineration. With the rising avenues of the suitability of coal as auxiliary fuel in fluid bed sludge incineration, an expansion of these concepts combines the use of coal or coal refuse as filter aid and auxiliary fuel. Lime¬stone addition controls SO2 emission.

Jan 1, 1985

How do you think the US Bureau of Mines closing will affect SME? The demise of the bureau represents a challenge, an opportunity and, above all, new responsibilities for our profession. A lot of good professionals are seeking new positions. A lot of worthwhile research is available for transfer to the private sector. Logic dictates that worthwhile projects of any defunded government activities should find support in the private sector. The bureau may be gone but its legacy is deeply rooted in the profession. The bureau’s contributions will be remembered as long as there are mines and miners. Its1994 research program was divided into three major areas: environ-mental technology; health, safety and mining technology; and minerals and materials science. There must be a place in either the government or private sector to continue these worthwhile activities.

Jan 1, 1996

By B. Cavender

Safety departments have traditionally been held responsible for the safety performance of their division or company. This approach leads to a lack of ownership of safety issues by the larger organization. An alternative paradigm is significantly more effective: the members of the work force (managers as well as workers) are fully responsible and accountable for safe production. The safety department is not extinct, however. Its role has changed, to focus on training, litigation, and external relationships such as community relations. This approach was implemented at BHP Copper's Superior mine and mill in Arizona. By obtaining the genuine commitment of the work force to accident-free production, the mill's MSHA incident rate immediately dropped from 7.4 to zero. The mill also ran one year with no MSHA citations. When this philosophy was implemented at the divisional level, the division's incident rate decreased from 9.5 to 1.1,an 88-percent reduction in six months.

Jan 1, 2000

By Corale L. Brierley

The depressed economic condition resulting from normal cyclic behavior, a more fundamental structural alteration, or both, is a mandate for change within the mining industry. Although several strategies for change have been proposed, the option of applying high technology processes to this smokestack industry offers the greatest opportunity for regaining global competitiveness and a new vitality. Research and development to secure new technologies require a corporate commitment for substantive change, a tech¬nologically enlightened management, a well¬funded and stable science and engineering effort, and a dedicated and motivated technical team--features in short supply in the mining industry today. However, an alternative to in-house development of frontier technologies is available to this beleagured industry through entrepreneurial, high-tech companies. These entities, with their dedicated focus toward product development, motivated and streamlined teams, high productivity and efficiency, and low costs offer a unique opportunity for large corporations to obtain high-tech products and services. These commodities are available through traditional commercial channels and an array of creative business arrangements. The latter offers notable benefits to large companies including windows on frontier technologies and mitigation of risk. Likewise, entrepreneurial companies profit through manufacturing and marketing relationships and an expanded financial base.

Jan 1, 1985

By G. A. Johnson

Basic management principles will be discussed (as they apply to minerals education efforts), especially in light of the changing nature of volunteerism in today’s society. Also, the “minerals education tree” will be presented, along with public opinion / public policy realities.

Jan 1, 2001

By Thomas D. Kaufmann

Introduction Mining has always been sensitive to the fluctuating income of downstream customer industries. The industry is now becoming more vulnerable to booms and busts as economic pulsations increase and demand for mining products shows little or no long-term growth. As the general economy has become more cyclical in the last decade, the capital-intensive primary industries have become more aware that timing as well as preparation of survival plans are vital in investment decisions. Strangely, however, some of us have not yet included the business cycle in our feasibility studies. Cyclic prices and volumes and fluctuations in profits and cash flows do not fit our linear models. The increased cyclical nature of our economy is recent and poorly understood. Forecasting peaks and troughs is still more an art than a science. Nevertheless, avoiding business cycle parameters can lead to error in value estimation and contingency planning of new projects. Metal and Mineral Industries More than half the iron and steel, aluminum, copper, lead, zinc, manganese, tin, nickel, molybdenum, cobalt, and chrome that we mine, smelt, upgrade, and recycle goes to construction, transportation, capital goods, and consumer durable industries. All are cyclical. Their products are consumed slowly, so replacement can be postponed in recessions. Purchases of such goods are usually financed by debt, and their customers are sensitive to highly cyclical changes in interest rates. During prosperous periods, people tend to buy capital goods despite high interest rates. Upstream industries also tend to be whipsawed by inventory cycles. With high interest rates and good transportation, downstream fabricators can lighten their inventories during recessions. They know that upstream suppliers can deliver supplies and raw materials immediately, And, with the advent of electronic accounting, the fabricator with timely inventory information can afford to hold fewer contingency stocks. Likewise, when recovery returns, inventories surge back through industry pipelines, accelerating demands on primary supplies. The price elasticity of most primary products is low. Their share of the value of finished products of the industries they supply is generally small. The 60 kg (130 lb) of aluminum in a car is vital. But whether it costs $80 or $130 will not visibly influence the demand for an automobile. With low elasticities of demand, the primary producer is hit with decreases (or increases) in prices and in sales volume, during recessions as well as recoveries.

Jan 6, 1984

By M. C. Roberts

The consumption of industrial minerals, like most other commodities produced from the earth, depends on the demand for the goods and services that use these materials. Minerals are not generally used directly by final consumers (table salt is a notable exception) but instead are used to either make products that are then purchased by customers, or the minerals are used to make industrial products that eventually contribute towards producing other goods and services. Therefore the demand for industrial minerals in most uses is derived from the ultimate demand for goods and services by consumers. The problem for producers of industrial minerals is that the demand for their mineral product fluctuates greatly in response to the changes in the production of goods and services over the course of the business cycle. In this respect, the producers of industrial mineral are innocent victims, subject to market fluctuations outside of their control. Because the demand for most minerals depends on the demand for the product and because minerals typically make up a minor portion of the costs of producing the product, changes in the price of the mineral often do not influence demand for it to a significant degree in the short run. This is described as a very low price elasticity of demand, as shown by the steep slope of the hypothetical demand curve in Figure 1. This demand curve shows that changing the price of the mineral does not alter the quantity demanded very much, but shifts in the demand curve will be the important determinant of the quantity of the mine.ra1 that is sold. The shifts are caused by the changing demand for the products using the mineral over the course of the business cycle.

Jan 1, 1994