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By James R. Jones

The tempo of air pollution control regulations has increased dramatically in the past few years. Because coal mining operations are frequently located in remote areas away from urban developments, specific regulations applying to coal mines have received lower priority and are thus only now being promulgated and/or enforced. Therefore, many mine operators are not yet familiar with the regulations and the impact upon their method of operations. Few have been faced with an inspector on the property sighting them for specific violations. Several of the Mid-western states are just now requiring permit applications to be submitted.

Jan 1, 1973

By William T. Ingram

Early in the 60's the author served as Chairman of the Engineering Foundation's Coordinating Committee on Air Pollution Research. One of our objectives was the development of a study on the measurement of stack emissions. Three publications of the Foundation resulted from these efforts to focus attention on the stack sampling problem.1,2,3 Two of these were annotated bibliographies covering 197 references. The third reported the results of a workshop meeting at which some 21 individuals from research institutes, industry and government discussed the possible and probable areas of research that would add to or increase the ease, precision and utility of sampling gaseous and particulate matter emitted from stacks. The American Society of Mechanical Engineers has had in its Power Test Codes a Standard Code for Determining the Dust Concentration in a Gas stream4 since 1941, The American Industrial Hygiene Association has published, in its Air Pollution Manual,5 a Section on Stack Sampling. Industry and regulatory agency requirements for stack sampling have utilized some modification of the alternatives in methodology. There has been ho single guide to stack sampling that met the needs of those who have the need to know.

Jan 1, 1970

By Charles H. Rice

Coal liquefaction processes can be divided into two broad classifications - direct and indirect. Direct liquefaction processes, in general, slurry coal with a solvent and react it with hydrogen under elevated temperature and pressure. Indirect liquefaction is the term applied to processes in which coal is first gasified to generate a synthesis gas of carbon monoxide and hydrogen. The synthesis gas is then converted to various types of liquid fuels by the proper selection of catalyst and conditions. The first experiments on direct coal liquefaction were undertaken in 1933 by Bergius. Development and commercialization of the Bergius concept was accomplished mainly through the effort of I.G. Farben at the Ludwigshafen plant of its subsidiary, Badische Anilin und Soda Fabrik A.G, under the leadership of M. Pier (1). A demonstration plat having an annual capacity of 100,000 tons of coal was built in Leuna, Saxony in 1927. Six years later, Imperial Chemicals Industries, Ltd., commissioned a plant in Billingham, England (2).

Jan 1, 1981

By Manuel S. Rivera

Abstract. Instrumentation in concentrators has evolved from a few isolated indicators to compu- terized control within twenty years. This evo- lution has caused a drastic change in the phil- osophy, personnel and equipment used in a pro- gram of servicing and utilization of present day automation.

Jan 1, 1980

By Robert B. Crookston

Oil from shale has been produced in foreign countries for more than a hundred years; however, except for short-lived, small operations, no commercial quantity of oil shale has yet been produced in the United States. Efforts to develop a viable oil shale process have been underway domestically for many years. At the present time, with the need for energy so urgently upon us, almost a dozen development ventures are underway or planned in Colorado and Utah. Of these several ventures, only Colony Development Operation has completed the development, testing and design of a ready-to-go 50,000 barrel per day com¬mercial project. Colony is a joint venture of the Atlantic Richfield Company, Ashland Oil Company, Shell Oil Company and The Oil Shale Corporation, more commonly known as TOSCO. TOSCO is the exclusive licensor of the TOSCO II retorting process and other oil shale technology, which includes mining, crushing and spent shale disposal techniques. This paper will deal, however, with only the materials handling aspects of the commercial oil shale operation. Oil shale handling for this infant industry is unique in that an understanding of the physical characteristics of the ore and the demands on material handling to the plant must he understood. Colony Development has completed ten years in the research and development of techniques and processes for mining, crushing and retorting raw oil shale and the disposal of spent or processed shale. A great deal has been learned about oil shale, in many cases confirming our intuitive analyses and the work of others, but more specifically we have brought it all together to a point where equipment performance and the specifications have been established and a design for the first commercial plant is now mature.

Jan 1, 1975

By Francesco Chiappalone, Daniele Nebbia, Lance Waddell, Greg Colzani

As part of the 3RPORT Project, a 5-mile tunnel is being excavated underneath the three rivers of Fort Wayne using a 19-foot diameter Slurry Tunnel Boring Machine. The groundwater pressure at the tunnel axis ranges from 4.5 to 5.3 bar. The rock mass hydraulic conductivity is very high with water inflows up to 10,000gpm imposing significant challenges to the project. After excavating 1,550-feet of the TBM tunnel, major leaks between the tailskin and the segmental lining were observed, indicating the potential deterioration of the tailskin brushes and the need for inspection and eventual replacement. The first part of the paper describes the planning of the intervention, including the design of the polyurethane grouting campaign, the procedures developed for the execution and the controls established during construction to timely assess the presence of potential hazards. The second part of the paper focuses on the experience gained during execution and lesson learned to prevent future occurrences of this nature.

Jun 13, 2021

By Thomas F. Clemens

This paper covers various changes in government regulations, taxation, and legislation for the past two plus years and the up- coming one. Part of the paper will discuss recent business conditions and how they have affected the cement and lime industry.

Jan 1, 1983

By J. L. Huiatt

Kerosine, fuel oil No. 2, vapor oil, and fuel oil No. 6 were separated into general hydrocarbon fractions by ion exchange chromatography and adsorption chromatography. The collecting properties of these fractions were evaluated by flotation of molybdenum and copper minerals from a natural chalcopyrite ore. Paraffin fractions and aromatic fractions of low polarity produced the best molybdenum recoveries. Selective flotation of molybdenite from copper sulfide minerals was not possible with any of the chromatographic fractions.

Jan 1, 1972

By Matthew Goff, Russell Lutch

The Great Lakes Water Authority (GLWA) operates the largest regional water authority in the State of Michigan. Two of the tunnels supplying raw water to the system from the Detroit River are the Springwells and Northeast Tunnels. The existing 70- to 90-year old concrete lined tunnels have experienced distress and cracking over their life requiring non-structural repairs to sections of the tunnels. For the repair, an interior stainless-steel segmental liner plate system has been designed to restore the watertight capacity of the tunnel liner and resist the exterior hydrostatic groundwater pressure in a dewatered condition. The team is utilizing a “wet repair” approach to perform the necessary repairs while the tunnel remains fully flooded and operational. To test and validate the tunnel repair approach, a full-scale mock-up of the proposed repair has been performed using underwater equipment and divers.

Dec 1, 2022

By D. J. Sweet, B. Seymour, T. M. Emery, M. Armatys, J. P. Bourgeois, W. Johnson

The Spokane Mining Research Division (SMRD) of the National Institute for Occupational Safety and Health (NIOSH) has partnered with a narrow vein, hard rock underground mine to research the effects of the binder content on the elasticity and post-peak ductility of cemented hydraulic backfill (CHB). This is part of a larger study to enhance the long-term integrity of ground support in underground mines. As mining advances deeper and stresses increase, CHB mix designs will benefit if they can be modified to handle higher levels of strain which are induced by an increased stope closure, typically affected by a reduction in stope width and increased mining depth, or through dynamic loading resulting from a local seismic event. This portion of the research examined the impact of reductions in binder and their impact on Young’s modulus, peak strength, and post-peak ductility.

Mar 2, 2022

By John Mahoney

We live in a world of change and the mining industry is enjoying some of the most rapid changes today that have been seen in a long time, We'd like you to open your mind to a new concept in material handling. Figure # 1 Shows a new concept combining some of the proven application advantages of the power shovel with which we are all familiar, and applies the advantages of the dragline for the benefit of the user. First, the hydraulic excavator enjoys tooth forces of the shovel because the dipper is attached to the machine with a dipperstick and boom, and can often actually realize greater tooth forces than a shovel because of the prize action of the dipper in hard digging. Second, the hydraulic excavator enjoys the application advantage of the dragline because both the operator and the machine are up above, sitting on top where the operator oversees the excavation and the machine's operating work range is greatly increased.

Jan 1, 1973

By Nathaniel Arbiter

The question of automation of concentrator operations with computer control is under increasing consideration. Some of the problems involved will be discussed from the viewpoint of the availability of the requisite, detailed knowledge of the unit operations. The justification for full-scale automation of a mill must ultimately be economic--an increase in profitability over and above the cost of instrumentation and development, Potential savings would be in three probable directions: decrease in operating labor costs by substitution of machine control; improved metallurgy through continuous effective control; and decreased operating costs by achieving higher unit capacities and process efficiencies.

Jan 1, 1962

By Carmel Bofinger, Maureen E. Hassall, David Cliff, Eric Stemn

e Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

By M. M. Hajdasinki

A project's rates of return (RORs)1, be it the internal rates return (IRRs) or one of the many IRR surrogates, frequently needs to be approximated. The success and efficiency an ROR- approximation procedure depend on the quality the approximation-initiating parameters, such as bounds or seed values (guesses). The existing approximation procedures commonly use bounds and guesses suggested by intuition rather than supported by mathematical considerations. This paper presents three mathematically founded ROR-bounding and eleven ROR-guessing approaches and examines their suitability by using examples of typical project cash-flowpatterns (CFPs). The calculated bounds and guesses not only improve the approximation efficiency, but also allow the process of the ROR discovery to be automated, thereby making it more convenient and reliable.

Jan 1, 1999

By N. Careddu

In recent years, slabs with a rough surface have captured a large share of the ornamental stone market. However, the main technologies used for this type of treatment are based on mechanical shock (bush-hammering) or thermal treatment (flaming or flame-finishing). These traditional technologies are widely used, but have many limitations that decrease their usefulness. The purpose of this study was to develop a technology that enhances the natural colors of the rock and produces a rough surface without compromising its mechanical characteristics, in contrast to traditional technologies. This report shows the technical, economic and aesthetic results obtained with a new water-jet treatment and compares it with competing technologies.

Jul 1, 2010

By Minor S. Jameson

This paper presents considerations in support of a U. S. oil import policy more restrictive than the present Government import program. A lower level of imports and greater long-range stability in the relationship between imports and domestic production are recommended. Reference is made to increasing world-wide surpluses of oil and wide disparities in foreign vs. domestic costs. Resulting economic forces are held responsible for the increase in imports (excluding residual fuel oil) of almost 300 percent and the change in ratio to domestic crude production from 5.4 percent to 13.9 percent during the period 1946-1956 prior to import restrictions. It is pointed out that these imports continued to increase during the years of import restrictions to a ratio of 17.3 percent of domestic production in 1961. Data are presented showing that increasing oil markets outside the United States provide an outlet' for more than 80 percent of total foreign production, with 90 percent of the increase in foreign production going to foreign markets. Attention is called to the fact that, if there had been no increase in United States oil imports during the past five years, foreign production would have increased by 45 percent in contrast to a static level of domestic crude oil production. The need for a less restrictive import policy in the interest of encouraging foreign oil development, therefore, is questioned. Declines since 1956 in the range of 30 percent in domestic exploratory crews, rotary rig activity and wildcat well completions in the United States are cited, together with a decrease of 9 percent in industry employment and increases of 9 to 18 percent in elements of cost. Recognizing that factors other than imports affect the domestic industry, it is concluded that continuing declines in the vigor, capabilities and competitive structure of the domestic industry can be expected unless further import restrictions are imposed. The public interest in assuring adequate domestic supplies is considered in the light of the role of oil and gas as a source of almost three-fourths of U. S. energy requirements and the economic benefits from petroleum production with a value exceeding the combined value of all other minerals in the United States.

Jan 1, 1962

By Dru Brown

More than 150 Mt (165 million st) of material crashed down at the Bingham Canyon Mine (Rio Tinto/Kennecott Utah Copper) near Salt Lake City, UT on April 10, 2013. The mine, one of the largest openpit mines in the world, ceased operations and evacuated personnel prior to the slide when it was discovered that material was moving at a rate of 5 cm/d (2 in./day). The slide destroyed the mine?s visitor?s center, buried several pieces of large mining equipment and severely hampered production. The Kennecott Utah Copper Corp. immediately began to assess the damage and look for options to reestablish operations. The highly unstable ground ? emphasized by another minor slide in September 2013 ? makes any cleanup efforts extremely dangerous. With terrain too dangerous for human operators, Kennecott was forced to look for alternatives that would help the company work on the treacherous slopes of the landslide while also keeping personnel safe.

Jan 1, 2014

By R. Lee Wooten, Marco D. Boscardin, James M. Taylor

An earth pressure balance (EPB) tunnel boring machine (TBM) and pipe jacking were used to construct a 430-meter-long segment of sanitary sewer force main. The force main was constructed by first jacking a 2045-mm-outside-diameter, reinforced concrete cylinder pipe (RCCP) casing through alluvial sands and gravels. Later, a 1220-mm-diameter, ductile iron carrier pipe was installed within the casing pipe. The main concern affecting the construction method selection was the elimination of the need for dewatering, which could cause groundwater flow from deeper, contaminated sands up across a silt aquitard into cleaner, shallower sands. In addition, the method selected reduced the volume of soil to be handled and, consequentially, the potential amount of contaminated soil to be managed. Items discussed in the paper include provisions for handling boulders and controlling ground movements as excavation and jacking occurred approximately 300 mm beneath an active,4800 kPa, 254-mm-diameter natural gas transmission pipeline.

Jan 1, 1997

By Gordon B. French

The Occidental Oil Shale mining and retorting system for the production of shale oil has many advantages over the conventional underground mine and surface retort systems. For example only a portion of the oil shale is mined and transported to the outside, where it blends with the existing shale talus found on most of the slopes in the immediate area. The retorted spent shale is retained underground so that it does not become a surface disposal problem. The process consumes only minor amounts of water which is produced in adequate amounts in the retorting to fulfill all mining operations needs without outside supplies. Noise and dust levels are kept to a minimum with most of the facilities located underground. The exception being the generating stations and facilities as required to monitor air and water qualities, and last but not least, more than four times as much oil is pro¬duced from a given acre than from conventional surface processing. With the increased thicknesses as available on the government monopoly area this number could be increased by a substantial amount.

Jan 1, 1975

By Peter A. Spencer

Much criticism has been levelled at bacterial oxidation over the quantities of air required for successful operation. Examination of the oxidation reactions and the assumptions concerning oxygen transfer made in the literature (1) indicate that the aeration requirements can be much less than those beirig suggested. Observations made on a large scale pilot test have confirmed reasonable aeration levels in extended site operation over a six month period. These aeration levels have implications for the engineering design and the power needed for aeration and agitation. Thus, these parameters effect both capital and operating costs as well as influencing the complexity of the design and normal operation. A number of companies have developed bacterial oxidation cultures intended for commercial ·expl oi tat.ion ( 2, 3, 4). Most of these cultures have been based on Thiobacillus and operate at temperatures between 30°c and 40°c. This temperature range limits their application in hotter regions unless means for both heating and cooling are provided in the design. Thiobacil!us cultures are also reported as not able to oxidize arsenic (III), which may limit the application of these cultures to successfully treat arsenopyritic ores and concentrates (5). BacTech (Australia) Pty Ltd has developed a culture which operates at temperatures above 4o0 c and which has been tested in a large site based continuous pilot plant at up to 55°c over a six month period. The culture showed resistance to high levels of soluble arsenic, allowing the arsenic to be retained in solution for control led precipitation and disposal. Data for. the arsenic precipitates indicated that these waste solids were relatively stable and, under the correct circumstances, were suitable for disposal into tailings dams without causing environmental problems.

Jan 1, 1990