Search Documents

By Suresh P. Babu, Joseph W. Leonard, Richard Muter, D. P. Sen

OUTLOOK FOR COAL UTILIZATION In 1975, about 650 million tons of bituminous coal and lignite mined in the United States was used to meet 55% of the primary energy input for electric power generation and 26% of the total industrial consumption.1 Even though this amounts to only 21% of the total energy requirements, it is believed that with the declining natural gas resources and uncertainty of liquid fuel imports, coal will assume a more dominant role in suppplying our future energy needs. A regional breakdown of the coal reserves of the United States along with their characteristics is shown in Table I. At present the United Stares Energy Research and Development Administration (ERDA) and the US Bureau of Mines (USBM) are financing extensive research programs in advanced mining methods and energy conversion processes. The increased demand for wal which may result from these research programs may also create large-scale environmental protection problems. As more and more coal is mined the production of undesirable coal fines and dust also increases proportionally. The USBM and the Environmental Protection Agency (EPA) research in this field includes development in the areas of instrumentation for qualitative and quantitative analysis of wal dust, protective devices, and dust collectors. Dust control by water sprays, steam, and foam are also being investigated. Other aspects of safety in mining include developing methane drainage techniques prior to coal mining, fire and explosion prevention, and neutralization and disposal of acid mine waters. It is the belief of coal technologists that when the emphasis shifts to coal as the primary source of energy. the existing methods of mining and preparation of coal must be improved considerably to supply large quantities of quality coal for energy conversion. It is the objective of the present large-scale research financed by ERDA to produce substitute fuels from coal. Large-scale gasification pilot plants are being constructed by Bituminous Coal Research, Consolidation Coal Co., Institute of Gas Technology, and the Pittsburgh Energy Research Center to produce coal gas of natural gas standards at 1,000 psig. The processes being adopted by these pilot plants are oriented towards recovering most of the sulfur from coal by absorbing H2S and its subsequent conversion to elemental sulfur. The environmental protection standards will be strictly followed in using the results of these pilot plants to construct large-scale coal gasification plants in the latter part of the 1970's. With the increasing awareness of the need for air pollution control, considerable research is being done to minimize sulfur dioxide emission from thermal power plants. Utilization of limestone and dolomite scrubbing systems and caustic treatment of stack gases have proved to reduce sulfur and nitric oxide emissions by about 90 to 96%.3 Currently, about 22 scrubbers are in use in the United States to reduce sulfur in stack gas emission. In the long-term, it appears that optimal combinations will be developed involving both advanced coal preparation technology and wet scrubbing. The sulfur compounds are converted either to elemental sulfur of sulfuric acid. Besides the sulfur compounds, the major byproduct of the coal utilization industry is the large amount of coal ash. The Coal Research Bureau at West Virginia University has developed a practical use for coal ash as a structural material. The coal industry will undergo revolutionary changes when coal becomes the primary source of energy. New coal mining and preparation processes will be introduced to meet the ever-increasing per capita energy requirements. 2. BENEFICATION Introduction Coal preparation, like the beneficiation of ores, is also aimed at the separation of values from associated waste. Even though the unit operations involved when enriching ores and coal are similar, there are certain characteristics unique to coal preparation. Unlike the scattered and concentrated veins of underground minera1 ores, coal is distributed uniformly and very much in abundance in the coal mines. Coal occurs as the metamorphosed sedimentary deposits of vegetable matter, while metal and mineral deposits occur in great varieties of forms, structures, and origin-from igneous to sedimentary and metamorphic. The mined coal, being much more friable than mineral ores, is subjected to less intensive size reduction operations. Ores are usually ground to a very fine size for subsequent concentration, while coal is crushed to a coarser size, since considerably less liberation is needed to achieve the desired degree of separation. Since mineral matter is to a great extent discretely distributed in coal, concentration is mainly achieved by taking advantage of differences in specific gravity between clean coal and associated waste. In general, about 90% of coal is concentrated using specific gravity separation and about 10% by froth flotation. In contrast, these operations are frequently reversed in the beneficiation of ores. In coal preparation almost all fractions separated during various stages are made use of. while large amounts of gangue material are rejected in the concentration of ores. Hence, coal generally has a much lower ratio of concentration than ores. Since ore deposits are frequently more variable and mineralogically complex than coal, beneficiation of ore may require more plant flexibility and point-to-point quality control. This characteristic difference between the mineral ores and coal is attributed to the generally used one-step processing in coal as compared to the multiple-step processing of ores. Dewatering to enhance the energy content of coal is usually considered a major unit operation. Even though thickening and filtration are common for dewatering ore concentrates and cleaned coal, vibrating centrifuges and disk filters find unique application in the coal industry for achieving these types of solid-fluid separation. In coal preparation, thermal drying is carried out in separate units at the mine. While ore concentrates are usually dried at the smelter. Although the drying of ores is seldom considered dangerous, volatile matter and combustible dust are reasons why the thermal drying of coal can be hazardous. Open air storage of ores and mined coal results in partial oxidation. Unlike the oxidation of ores, the oxidation of the pyritic and carbonaceous constituents of coal together with the heat of condensation of moisture contribute to spontaneous heating and the subsequent combustion of coal in storage. Among the other significant difference between concentration of ores and coal are the weight and capacity of processing equipment. Coal processing employs less cumbersome, higher capacity units while the beneficiation of ores usually requires much more massive and frequently lower capacity equipment. Properties of Coal Which Influence Design The widely varying and heterogeneous composition of coal, due to metamorphism, determines the preparation design and uses of the resulting products. Petrography serves as a useful system of classification to identify the coal types present and their distribution. Early

Jan 1, 1985

By Raja V. Rarnani, Robert L. Frantz

"The more than 75 research projects funded throughout the first 10 years of the Dust Center's operation have resulted in numerous cumulative findings fulfilling the goals of the Center. These project descriptions present the methodologies and project-to-project relationships leading to their various accomplishments and demonstrate the mesh between project objectives and Center goals.To develop equipment for collecting respirable dust samples.To develop experimental methods for particle-by-particle characterization of morphology, size, and chemistry.To develop experimental methods for overall respirable dust sample characterization of size distribution, chemistry, and crystallography.The project directly addresses the Center's goals to enhance the understanding of the scientific and engineering characteristics of fine and respirable mineral particles found in mining and milling atmospheres and to establish the relationship between natural and cultural factors (mine geology, mineralogy, mining and milling methods, equipment, and control measures) in the generation of fine particles. The project also aims to contribute to the development of control mechanisms for reducing ambient respirable dust concentrations and worker exposures.The work on this project is related to similar work on Coal Mine Dust Characterization (Project No. 2701/MN1) and Characterization of Dust Particles (Project No. 4203/PS3).Airborne dust sampling was performed at the following locations: 1) a sand and gravel quarry in Southern New Hampshire, 2) a welding facility, 3) a ceramic powder facility, 4) a metal powder facility, and 5) the air in Cambridge, Massachusetts. A portable sampling box incorporating two Sierra personal cascade impactors was designed and produced. At a 2-LPM flow rate, the effective cut-off diameters of the Sierra impactors were 10.0, 6.0, 3.5, 2.0, 0.9, and 0.5 mm, respectively, for each stage, and the air passed through a PVC filter after the last stage. In addition, the sampling box contained a total respirable dust filter. The substrates were weighed carefully before and after collection, and the weight increases were recorded. All films, foils, and filters were put in the balance chamber for more than 8 hours to stabilize the temperature and humidity before weighing. A Cash 21 microbalance (±0.001 mg) was used to weigh the Mylar films, SS films, and filters."

Jan 1, 1995

By Reinhardt Thiessen

Views and conceptions of the origin, composition, and general nature of coal differ so widely that to determine the real extent of actual knowledge is no easy matter. The chemist finds difficulty in attacking the chemical problems and the engineer lacks a broad chemical basis for the study of his problems. Thus the economical and efficient utilization of coal in the industries suffers from a lack of knowledge of the composition of coal itself. Most scientists interested in this matter, as has been brought out in discussions during the recent investigation of coal problems, appear to have only a vague idea of the components of coal and their origin. Some are even in doubt as to whether substances derived from the wood and resins of plants form a part of coal; and few seem to have more than the dimmest idea of what are the components of coal, the condition in which these now exist, and the transformations that they haye undergone. Although during the paiilt century or more many co.rrect observations have been made and recorded, these were falsely or inadequately interpreted, so that many of the interpretations rendered are contradictory. As a result there has been great confusion. Many of the observations made in the past, although accurate and correct, could not be explained, because the principles involved in a correct solution of the problem were not then known. For example, Parkinson, Hutton, Petzhold, Guembel, and others made valuable discoveries regarding the processes by which plant substances are transformed into coal, but as the principles involved are those of colloidal chemistry, a science not known to the scientific world of that time, the observed facts could not be interpreted and the solution of the whole problem was blocked. The explanation of the true meaning of the alternating bright and dull bands so familiar in all ordinary bituminous coals afforCls another example. This banding has been observed and recorded from the earliest times, and has led to the forming of many false theories. Some gAologists, for example, have endeavored to explain the bands as due to alternating climatic conditions during the coal-forming period. Had the geologists known the true nature of coal they could not have made this mistake nor many others made in the past. To fill in a few of these gaps and to clarify some of the existing confusion is the aim of this paper. The immediate cause that led the author to investigate further the composition of coal and the origin and structure of its constituents was that when an attempt was made to discover the meaning of the coking and noncoking properties of coal a more exact knowledge of the nature of coal was required than was then available.

Jan 1, 1920

By Thomas F. Connors

The end of an era is here. The pony-express era of industrial relations in the coal industry is ending. Those professionals who know it must end to insure the industry's future are happy, relieved, but somewhat saddened. They are sad because it did have its elements of suspense, thrills, frustrations, and at times, plain fun. The days of the Company town are ended; the wildcats are declining; violence (while a big part of today's industrial relations) is beginning-to decline. The spirit of sound industrial relations is beginning to take hold. This has to happen for the industry to compete in today's economy and it is causing major changes for those who have grown accustomed to the pony-express type industrial relations.

Jan 1, 1981

By Karl J. C. Harries

"12.1. NO DEPRECIATION/GAAPAll calculations and computations relating to the Royalty shall be carried out in accordance with generally accepted accounting principles consistently applied to the extent that such principles are not inconsistent with the provisions of this Schedule and the agreement attached hereto, it being specifically agreed that nothing herein contained shall permit, or be construed to permit, the Operator to deduct any amount for depletion, depreciation, amortization or any deduction that represents a non-cash outlay.Comment: In cases like net profit royalties where recoupment of prior expenditures is permitted, care should be taken to avoid any implication that depreciation may also be taken. It is only logical and equitable that Property Owners should not be permitted an apparent ability to “double dip” with respect to deductions. A provision like this example should accomplish the task. It will be noted that the example specifically contemplates that the negotiated arrangements will prevail over any requirements of GAAP. Accordingly, if the parties agree to an unusual formula for recoupment, it will not be set aside to accommodate GAAP requirements. Under GAAP, revenues and expenditures are accounted for on an accrual basis. In addition, it specifically prohibits the taking of non-cash deductions, which is in keeping with the concept of recoupment.Although in some ways the example states the obvious and could be considered redundant, its presence, especially in provisions contemplating recoupment, makes it clear to the financial people that there may well be some variations from normal practices dictated by GAAP, while at the same time confirming the availability of GAAP to fill any voids.The accounting profession often makes the caveat that application of GAAP is an “art”, not a “science”. GAAP do not provide a cure-all and can create problems that will have to be addressed. For example, GAAP contemplate that asset costs are to be reduced by investment tax credits, which can cause a problem for a payor with more than one mine."

Jan 1, 2003

Andy H. Vassiliou – Introduction Ladies and gentlemen,.good evening and welcome to the Paul F. Kerr Memorial Symposium dinner. I believe we are all here to honor the memory of a great teacher and advisor, and a true friend -- Professor Kerr, or Dr. Kerr, or to most of us who were his students, "Pappy" Kerr. Most of us who attended the Paul F. Kerr Memorial Symposium earlier today at the New York Hilton had the opportunity to read, or listen to, or discuss scientific papers presented in honor of Dr. Kerr. In addition, all of the speakers had the opportunity to reminisce about their association with Dr. Kerr, who was credited as having contributed substantially to their graduate education and the development of their careers. Dr. Kerr's two daughters -- Ruth and Nancy -- who attended the Symposium at the Hilton are also here with us tonight. I think we should keep tonight's festivities on an informal basis since we are all old friends or former students of Dr. Kerr. Some of us may want to say a few words about our experiences at the time we were students at Columbia, and hopefully include some anecdotes relating to Professor Kerr. I would like to invite everyone to do so, but first we have arranged for two of us to be the lead speakers, whom I will introduce in a few moments.

Jan 1, 1985

By Robert L. Lappi

Eight interburden handling concepts are developed for multiple seam area mine stripping operations in central and western United States. They are based on data gathered and analyzed during field surveys, literature reviews and visits to state regulatory agencies in five states. It is concluded that improvement of reclamation practices through selective interburden handling techniques is possible at lower operating costs than currently incurred. Specific multiple seam mining systems are discussed in this report.

Jan 1, 1980

By John Lohrenz

Consider an investor who, knowing future costs and revenues, can choose how rapidly to produce from a given mineral source. If the investor elects to make that choice to maximize present value of future profits, how do policies affect the choice? Various alternative policies are examined. Some, such as higher royalty rates, lead to slower production rates than would otherwise obtain. Clearly, the chosen rates of production are policy-dependent. One is wisely counseled to consider how mineral policies affect the rate of production from given sources when analyzing current and alternative policies.

Jan 1, 1982

By J. R. Thoenen

The objective of this circular is threefold: First, to describe briefly the various modes of occurrence of sand and gravel. Second, to emphasize the need for adequate prospect¬ ing and exploration prior to the expenditure of funds for development and plant construction. Third, to describe various methods of prospecting and exploration and their application to the several modes of occurrence of sand and gravel. Sand and gravel may be found in nearly every county or township in the United States. Commercial deposits, however, are by no means so widespread. The introduction of concrete and the consequent impetus given to consumption of gravel and sand aggregates has seriously depleted deposits in some congested areas. Increasing re¬ strictions in the specification requirements for marketing sands and gravels have further narrowed the economic areas. On the other hand, the combination of increasing transportation costs and decreasing selling prices has forced the decentralization of gravel production. As a result smaller, intermittently operated, and widely scattered portable or semiportable unit plants have been encroaching on the territory formerly supplied from centrally located pits with large tr.atment plants. Generally speaking, the small portable plant can not produce any great variety of ma¬ terials to as exacting specifications nor as economically as the large permanent plant.

Dec 1, 1932

By A. K. Raji, E. F. Orumwense, M. O. Ojumu

The Fourth Industrial Revolution has driven significant advancements in autonomous robotic systems, particularly in subsea exploration and offshore mineral dredging. This review examines the latest developments in electrically powered quadrotor-track subsea robotic crawlers, highlighting their potential to enhance efficiency, mobility, and adaptability in challenging underwater environments. The integration of advanced automation, artificial intelligence, and real-time control systems has paved the way for more effective robotic solutions in offshore mining. This study explores the dynamic performance of hydraulic crawlers to quadrotortrack robotic dredgers, focusing on their propulsion, navigation, and stability under high hydrodynamic conditions. By leveraging state-of-the-art technologies such as lithium-ion battery power systems, intelligent microprocessors, and sensor-based control mechanisms, these robotic crawlers offer a promising alternative to conventional subsea excavation methods. Furthermore, the review analyses recent experimental and simulation-based studies that assess the feasibility and performance of these systems in real-world applications. The findings of this review provide valuable insights into the role of 4IR in transforming subsea robotics for offshore mineral dredging. By addressing existing limitations and identifying key technological advancements, this study contributes to the ongoing development of nextgeneration robotic systems capable of operating efficiently in extreme underwater conditions

Jan 30, 2026

By George Vranesh

Synfuels development in the upper Colorado River basin and the population growth attendant with such development demand sizeable quantities of water. Unfortunately, the water supply in the basin is limited and such limitation may impose a significant constraint on the development of the West's abundant energy resources. Although the water for the synfuels development will be governed by the law of prior appropriation adopted in the upper basin states, the authors point out that an apparently senior water right .my not deliver a firm supply of water. The federal and Indian Reserved Water Rights Doctrine, the Colorado River Compacts the Doctrine of Equitable Apportionment, and the federal and state environmental laws can all severely diminish the value of any given water right and the synfuels industry should take care to evaluate these factors in acquiring its water.

Jan 1, 1981

By Karl J. C. Harries

"4.1. INTRODUCTIONThis chapter, although divided into four parts, deals with only two principal topics. The first briefly describes and discusses some common types of property interests and considerations relating to them and the second deals with entering upon privately owned lands and obtaining the consent to do so.It should be noted that the terms “mining rights” and “mineral rights” are used interchangeably. As so used, they include the right to exploit the minerals and dispose of them for the benefit of the owner/lessee. This is relatively common in common law jurisdictions. In some jurisdictions, the two terms have distinct meanings, with “mining rights” referring to the right to work or exploit the minerals and “mineral rights” referring to the minerals themselves.Finally, it must be mentioned that the comments in the Introduction and §§ 4.2., 4.3. and 4.4. are based primarily upon Ontario law and Ontario’s mining and real property systems of registration. They have been included for illustrative purposes.4.2. LICENCES, CLAIMS, AND LEASESIn most jurisdictions, there are several basic types of interests that can be obtained from the state for mining purposes and that are of interest to the explorationist, as opposed to the operator. Different jurisdictions will have variations of these and possibly some extra ones that will address special purposes or local concerns. In virtually every jurisdiction, privately owned property rights are obtained through negotiation between owner and acquiror.Exploration or prospecting licence. This licence grants to the holder the right to prospect over a large tract of land and the exclusive right to acquire mining claims within that tract for the term of the licence. Such licences are usually negotiated documents requiring a minimum expenditure during the first year (often secured by a deposit or surety bond) and minimum annual expenditures thereafter to continue the licence in force up to its full term. The term will rarely exceed four years. The number of claims permitted to be staked will be limited in some way, possibly as to a maximum aggregate area or a maximum number of claims per annum. It is normal for the holder to have to drop part of the licensed area each year, so that the area shrinks annually, although exploration expenditure requirements will usually increase.These types of licences are usually used by governments to encourage exploration of otherwise unattractive or remote areas, such as the far northern parts of some of Canada’s provinces. They do not grant any real property interest in the area for which they are issued, and they will be subject to any claims or property rights that exist in the area. They are contracts with the state that grant certain exclusive rights in return for commitments to carry out work. They may or may not be specifically authorized by statute."

Jan 1, 2003

By John M. Hill

Automation technology has many facets, some well tested and proven, some yet to be put to the acid test of economic reality. In this paper, we will limit our purview to the former. Consider, if you will, an automated handling system combining high-speed conveyors and automatic devices on-line which not only provide signals for routing and sorting, but also format those signals for the production of manufacturing, inventory, shipping and billing paperwork. This is not futuristic, but practical and a realistic accomplishment. Therefore, the following discussions will address today's challenges not with tomorrow's solutions, but rather, with an established technology which is playing an increasingly prominent role in materials handling systems. Until recently, relatively modest importance has been attached to the timeliness of information feedback from the production or assembly line, warehouse or distribution center. Thus, initial applications of automatic identification equipment focused almost exclusively upon the control of materials flow - that is, routing, sorting, etc. However, these systems have performed successfully and quietly established an enviable track record as reliable materials control tools.

Jan 1, 1973

Jan 1, 1948

Jan 1, 1948

Jan 1, 1943

Jan 1, 1923

Jan 1, 1943

Jan 1, 1936

Jan 1, 1936