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By H. S. Sichel

"The valuation of diamond ferous deposits depends on (i) the density distribution, (ii) the size distribution of stones and (iii) the selling price structure prevailing at a particular time.In the density distribution the stochastic variable is defined as the Dumber of individual stones found per sample unit irrespective of the stone size. The density distribution is discrete and allows for barren sample units.As diamonds often occur in clusters, a Poisson mixture distribution is derived which is entirely new, as existing discrete distributions cannot represent the stone number frequencies found in nature.For the sizes of diamonds, which are measured by weight, a new compound logarithmic normal distribution is developed.Combination of (i), (H) and (iii) leads to a meaningful appraisal of diamond ferous ground expressed in monetary value per production unit of mining.Finally, confidence limits are calculated which allow for inference from sampling to recovery."

Jan 1, 2014

By J. D. Cooper, D. W. Thompson, J. Basiuk, W. Cass, R. Ilves

The Department of Thoracic Surgery and Pathology at the Toronto General Hospital have had a long standing interest in the early detection and treatment of carcinoma of the lung. Our initial experience was with a population at risk due to a prolonged period of cigarette smoking. More recently our efforts have turned to industrial exposure, specifically in the nickel and uranium industries. [Initial Screening Project] (1) For a three year period 1963 to 1966 a cytology screening program was carried out through the Out-Patient Department. The study was limited to cigarette smokers over 40 in age. A total of 1586 patients were examined. Of the sputa collected, the classification is seen in Table 1. There were 11 malignant sputa present. Added to this number were 25 patients with symptoms, normal chest X-rays, but malignant cells on cytology, and a further 5 patients in whom an abnormality (eventually proven non-malignant) showed on X-ray, and sputum showed malignancy which was radio logically occult. (Table II). This gave a total of 41 patients with malignant sputum who were evaluated between 1960 and 1966. The clinical course of these patients is seen in Table III. Only 19 of 41 patients had localization and treatment of their tumour during that study period and this low rate of localization attests to the technical difficulties endoscopy in that day presented. The method of localization was as follows: a) 6 patients showed an area of segmental pneumonitis somewhere in this time period b) Using the rigid bronchoscope localized the tumour in 9. This was proven by direct biopsy, and frequently required more than one bronchoscopy over a prolonged time period. c) bronchograms and tomograms showed abnormalities in 5 patients. Of these 19 patients, 5 were treated by radiotherapy because of general condition or refusal of surgery. Three of the irradiated patients died of recurrent cancer within three years. The other two died within one year of unrelated disease. Fourteen patients underwent resection, with one operative mortality. At pathology, the tumours were "in situ" in 6 and invasive in 13. There was no evidence of nodal spread. When last followed up in 1979, there were no cases of recurrent tumour and no cases of second lung primary tumours. Similar experiences have been reported from the Mayo Clinic (2), Johns Hopkins (3) and Memorial Hospitals (4). Early detection of radiologically occult tumours which are in situ or minimally invasive has given uniformly good results. There have been no deaths from recurrent or metastatic cancer in surgically resected patients, and only one second primary tumour has been detected. Interestingly, the Hopkins group reports that 5 patients with Stage I squamous cell tumours refused operation. One refused any treatment and died of disease at 12 months. Three were radiated, and were alive from 14-38 months post-treatment, all with evidence of recurrent disease. [Sudbury Sintering Plant Study](5) From 1948 to 1963 an open travelling-grate sintering process was employed to convert nickel sulfide to nickel oxide at an International Nickel Company operation. The environment in this plant was particularly dusty and filled with fumes. It became apparent by 1969 that the incidence of bronchogenic carcinoma was markedly increased in workers from this plant. A concerted effort was made to track down all workmen with this exposure. During 1973 and 1974, 268 men were studied. Chest radiographs were done and showed no mass lesions. Sputum was collected on three consecutive days and analyzed. There were 12 men with malignant sputum, all of the squamous cell variety. Two refused any investigation, one presenting 31/2 years later with extensive hronchogenic carcinoma, and the other 5 years later with extensive carcinoma of the maxillary sinus. In the remaining ten patients careful rhinolaryngeal examination as well as a detailed bronchoscopy, involving examination, brushings and biopsy of all pulmonary segments was carried out. One patient was found to have laryngeal carcinoma and was treated by radiation. In nine patients, the malignancy was localized to the lung, leading to six lobectomies, two pneumonectomies and one sleeve lobectomy at operation. However, the follow-up in these cases suggests a different biological behaviour with these industrially related tumours. While no tumour has recurred locally, one patient has died of metastatic cancer and two patients have developed second and one patient a third pulmonary primary cancer. However, survival has still been much better than wits radiographically manifest lung cancer. [Technique of Localization] (6) Following a careful rhinolaryngeal examina examined and then the lower respiratory tract is examined. This is all performed under general anaesthesia. The trachea is examined with the rigid Jackson bronchoscope, collect-

Jan 1, 1981

By K Hooper

Over the past 20 to 30 years statistics as a science has grown in significance. Not a day passes without reference to the latest statistics by the print, audio and audio-visual media. The Northern Territory Government has been part of this growth and like other public and private sector organisations collects a broad range of statistics. The Northern Territory Department of Mines and Energy participates in the government's statistics collection process. Statistics collected and published by the Department of Mines and Energy include geoscientific; mining and exploration tenure; environmental (e.g. mine site waste water management); production of minerals, oil and gas; mining sector employment; and occupational health and safety. The importance of statistics collection to the Northern Territory Government is discussed in the paper.

Jan 1, 1994

By E. Z. Lajtai

The probability distribution of fracture data from a rock mechanics test contains information about the effectiveness of the testing procedure and/or about the nature of the operating failure mechanism. The tensile strength of Lac du Bonnet granite forms a bimodal probability distribution when determined through line loading as in the Brazilian test. The same data obtained from three point bends tests are unimodal. The bimodality can in part be removed by distributing the line load over a finite area. Moisture has the anticipated effect in lowering both the average compressive and the average tensile strength of Lac du Bonnet granite. The reduction in strength however is not uniform within the probability distribution; the change is the largest at low and the smallest at high strength. Conversely, long-term loading is more damaging to the high strength members of the distribution. The large scatter of failure times in static fatigue experiments can in part be removed or even utilized when the probability distribution of instantaneous strength is taken into account.

Jan 1, 1982

By H. P. Greenwald

IN the year just passed the Coal Division's Committee on Rock-Dusting reviewed the status of this safety measure in American coal mines and prepared a paper thereon which will be presented at the February meeting of the Institute. This paper supplements one appearing in Vol. 139 of the "Transactions," page 87 (1940). Because that paper will be issued soon, only a summary is given herein.

Jan 1, 1944

By Mike Muchard

Augered cast-in-place piles are one of the most cost effective deep foundation options available to designers but have been largely underutilized due to skepticism associated with quality assurance and hence capacity. When installed correctly, unit friction values can rival any other competing foundation system. To this end, many means have been implemented to increase confidence in the competence of the foundation. One such method is load testing via the Statnamic test method. This paper presents an overview of the Statnamic test method, advantages and disadvantages of its use, and several case studies where Statnamic testing of augered cast-in-place piles confirmed quality construction, brought about design changes, or proof tested problematic installations.

Jan 1, 2000

By J. J. Gusek

Several final pits in the Seneca No. 1 Surface Coal Mine were abandoned in the 1960's without being reclaimed. In addition, a progressive landslide aggravated by the abandoned mine land conditions was threatening a county road and private property. An AML-funded project to stabilize the landslide and reclaim the final pits was completed in 1986 for the Colorado Division of Mines and Geology (formerly Colorado Mine Land Reclamation Division). The site was visited after ten growing seasons. The land is stable and the vegetation re-establishment is strong. Volunteer native plant species are now invading the reclaimed sites.

Jan 1, 1997

By HERBERT G. MOULTON

FROM prehistoric times to our own day man has struggled against extremes of climate. Human life, originating in semi-tropical or temperate areas, was unable to progress into the northern latitudes until fire was discovered and some form of clothing provided. It was found possible to maintain life even in the hottest parts of the tropics, but only at a great sacrifice of comfort and efficiency compared with the more temperate zones, or in cooler areas with the protection of clothing and artificial heat. It was no accident, but the natural result of climatic conditions, that efficiency became the greatest and civilization the most advanced in areas where the natural climate was favorable, or in cooler zones where protection against severe cold could be se-cured by relatively simple methods of conserving or producing heat.

Jan 1, 1933

By D. Christofferson

As an alternative power source to eliminate trailing cables, ESD Corporation is installing a flywheel system on a shuttle car. Flywheel power is extracted by a high-speed generator, developed by Lear Siegler Corp., and the system -- including vacuum and lubrication and cooling auxiliaries -- is supplied by the aerospace group, Rocketdyne Division of Rockwell International. The flywheel system is being developed under a three-year contract with the Department of Energy. It is a follow-up contract to a previous DOE-contracted study by General Electric Co. in which it was shown that a flywheel can be a feasible power source for a shuttle car from technical, economic, and safety standpoints. This paper addresses the status of the program, design decisions established, and plans for laboratory test procedures and underground demonstration. The flywheel-powered shuttle car is a conventional 6-ton capacity shuttle car equipped with a 7-rotor flywheel energy storage package. The energy package is the sole source of power for the shuttle car through a complete mission duty cycle (MDC) of tramming to the miner, receiving a load of coal, and returning to the secondary haulage system. Energy stored in the system exceeds MDC requirements and waiting times to provide an ample margin of reserve energy. The energy storage system is recharged by spinning the rotors back up to maximum speed each time the shuttle car comes back to the seconaary haulage system. The electrical charge motor is connected to a power source to recharge the system while the load of coal is being discharged.

Jan 1, 1981

By D. Christofferson

As an alternative power source to eliminate trailing cables, ESD Corporation is installing a flywheel system on a shuttle car. Flywheel power is extracted by a high-speed generator, developed by Lear Siegler Corp,, and the system -- including vacuum and lubrication and cooling auxiliaries -- is supplied by the aerospace group, Rocketdyne Division of Rockwell International. The flywheel system is being developed under a three-year contract with the Department of Energy. It is a follow-up contract to a previous DOE-contracted study by General Electric Co. in which it was shown that a flywheel can be a feasible power source for a shuttle car from technical, economic, and safety standpoints. This paper addresses the status of the program, design decisions established, and plans for laboratory test procedures and underground demonstration. The flywheel-powered shuttle car is a conventional 6-ton capacity shuttle car equipped with a 7-rotor flywheel energy storage package. The energy package is the sole source of power for the shuttle car through a complete mission duty cycle (MDC) of tramming to the miner, receiving a load of coal, and returning to the secondary haulage system. Energy stored in the system exceeds MDC requirements and waiting times to provide an ample margin of reserve energy. The energy storage system is recharged by spinning the rotors back up to maximum speed each time the shuttle car comes back to the secondary haulage system. The electrical charge motor is connected to a power source to recharge the system while the load of coal is being discharged.

Jan 1, 1982

By Gerald R. Coonan

I'm really here to talk about my pet subject of government relations. I've been in Peabody's Environmental Quality Department, working on regulations, for over five years, and I have seen a number of individuals in the coal industry who were completely stunned when a new regulation was brought to their attention. Their first reaction was, "where did this come from"?

Jan 1, 1980

By D Bruggemann, F Sereshki

There has been an ongoing research on coal and gas outburst for the past two decades at the School of Civil, Mining and Environmental Engineering, University of Wollongong. Research study began with a humble beginning, initially conducting basic laboratory studies on the coal and gas properties, progressing into the determination of gas content of coal by sorption technique and the effect of gas pressures on coal strength. The present laboratory facilities and research interests are extended to include the study of coal permeability and shrinkage properties and their effect of gas drainage characteristics with respect to gas type, and pressures. All the changes are examined with respect to changing in-site geological conditions of the coal deposit investigated. The aim is to provide a long-term support to industry in establishing a data bank for Australian coal deposit characteristics and properties.

Jan 1, 2005

By FRANK COLE

THE territory covered in this discussion includes all the states west of the Mississippi river. Agriculture is expanding each year in this section, but until recent years the application of commercial fertilizers as an aid to crop production was not practised to any great extent. The use of commercial fertilizers has increased somewhat, but is still on a small basis as compared with the tonnages used else- where in the United States. During 1928 these western states used 665,100 tons of all classes of fertilizer as compared 'with 7,933,600 tons used in the whole United States; or this western area, compromising near- ly two-thirds the land area, uses about 5 per cent of the total fertilizer. To show how large a tonnage one state may consume, North Carolina for the year 192s used 1,349,360 tons of commercial fertilizer or about twice the amount used by 22 western states.

Jan 1, 1930

By C. R. McClure

The objective of this papef is to summarize briefly the practical use of rock mechanics in design and construction of various types of structures. These range from foundation for industrial facilities, nuclear power plants, bridges and dams to tunnels and underground caverns. The use of rock mechanics has varied from performing a few laboratory unconfined compressive tests on core samples to complete field and laboratory tests for underground power caverns. The primary difference between the rock mechanics studies we hare for construction projects and those most commonly found in the literature is that our tests must provide immediate answers to specific questions facing a design or construction engineer. For example, when we make a plate-bearing test we arrive at a load-deformation relationship. We realize that this is not a true modulus of elasticity. Yet, when considering the resistance the rock will provide against forces occurring in a pressure tunnel it is a far more useful value than the true modulus of elasticity of the rock. Another example of this difference in interest is in the use of flat jacks. Many people criticize the use of flat jacks because they measure the stresses in the disturbed zone very near the surface and do not represent the undisturbed stress condition in the rock. However, in actual construction it is frequently those near-surface stresses with which we must cope. We are interested in both the stress conditions present prior to excavation and those as modified by construction of an exploratory adit or drift. Fundamentally, we are interested in the practical application of rock mechanics in the solution of problems of design and construction of civil engineering works.

Jan 1, 1968

By R. A. L. Black

Rock mechanics is a very new science. It has been accepted as a recognized discipline for some two decades, but it is only within the last five to ten years that it has been common to include the teaching of rock mechanics as a separate subject in undergraduate curricula at universities. Thus, few senior mining engineers practicing in industry, either men in charge of production or those engaged in mine planning and design, are familiar with the subject. That this unfamiliarity has continued so long is also due in part to the fact that the results of rock mechanics investigations have been published in a large number of different periodicals covering subjects ranging from experimental stress analysis to obscure branches of applied earth sciences. The first really useful textbook ' in the English language was published only in 1965, in Canada. It made available to students and to practicing engineers, for the first time in concise form, the essential body of accepted knowledge about rock mechanics and developed the theories on which it is based in a simple, clear and logical manner. Another factor which has resulted in rock mechanics science being slow to be accepted by the mining industry is that research work has often appeared to be esoteric and unpractical. Senior engineers have been reluctant to spend money on the application of new knowledge when the process of application seemed uncertain and ill-defined, and where the cost of field investigations (which is necessarily high) appeared to offer no certainty of economic reward. This is a reasonable attitude on the part of mining engineers; they are responsible to skeptical boards of directors whose chief concern is, very properly, the net return on capital invested. The application of rock mechanics science has not in the past,

Jan 1, 1968

By Hyun Soo Kim, Joon Soo Kim, Myong Jun Kim, Jyothi Rajesh Kumar, Jin-Young Lee

Rare earth materials have an ever growing variety of applications in the modern and hitech technology. They apply to many an industry with crucial materials and they provide numerous a customers with benefits. Rare earth materials utilization increasing day-by-day in the worldwide, at the same time the resources is very limited in many countries like Korea. The present general article divided four sorts such as 1) mineral processing of Korean ore deals the gravity, magnetic separation and froth flotation, 2) decomposition and leaching of concentrates included sodium hydroxide fritting, sodium hydroxide hot digestion, hydrochloric acid leaching, 3) separation and purification of rare earth elements in mixed rare earth chloride solution consists reduction and oxidation method, solvent extraction, 4) preparation of rare earth oxide compound from purified elemental rare earth chloride solution having oxalate salt precipitation by reaction crystallization. The last part consists of a summary of the present study.

Jan 1, 2015

By William C. Howe

This paper describes the technical status of the atmospheric pressure fluidized bed combustion (AFBC) process for utility steam generation. Major areas where AFBC development work is needed are discussed. Various approaches to solving these key issues are identified and the ongoing research and development programs addressing the key development areas are described. Other significant programs pertaining to the development of AFBC for utility steam generation are also discussed and needs for future work identified.

Jan 1, 1978

By H. Y. Sohn, Y. Mohassab, D. -Q. Fan, M. Elzohiery, A. Abdelghany

The Flash Ironmaking Technology being developed at the University of Utah is aimed at producing iron directly from iron oxide concentrate. In this technology, the concentrate is reduced by H2 and CO gas mixtures formed from the partial oxidation of natural gas in a flash reactor. Natural gas represents an economically and environmentally superior reductant/fuel for the flash ironmaking. The rate equations for the reduction kinetics by H2, CO and H2 + CO gas mixtures were determined in the temperature range 1150–1600 °C. These rate equations were applied to experimental results from a laboratory flash reactor using Computational Fluid Dynamics CFD simulation. A new mini-pilot reactor, which is capable of operating at 1150–1550 °C with a concentrate feeding rate of 2–5 kg/h, has been installed. Commissioning of the reactor with an emphasis on preheating of the reactor, production of reducing gas mixtures and the feeding and collection of iron ore concentrate and product particles has been completed.

Mar 1, 2017

By Herbert Hoover

IT is always a pleasure for me to join in the Ameri-can Mining Congress, for not only has my own professional life been closely linked with the industry, but the Secretary of Commerce is specifically enjoined in the organic act creating the office to promote and foster the interests of the mining industry. And it is a vital part of our national life. It is one of those indus-tries without which. the nation could not go on for a week. It ranks second only to the agricultural industry in its contribution to our raw materials. Its production amounts to nearly 6 ½ billions annually, providing direct support to probably ten millions of our people through employment to about two million workers. But the in-dustry has a greater importance than even these figures indicate, for with agriculture, forestry, and water power it furnishes the raw materials upon which the whole work of our civilization rests. When the raw ma-terials of our mines emerge. from manufacture with the added expenditure of labor and capital upon them, they have a wholesale value of over fifteen billions of dollars. And in this, the second stage of their application, they give employment to another two million workers and support to about ten million more of our people. A large portion of these manufactured commodities must filter through the retail trade; their total value when delivered to the consumer exceeds twenty billions of dollars. And from this distribution arises the support of many more millions of our people. It is estimated that the products of agriculture when they reach . the consumer, with transportation, manu-facturing, and distribution costs added, have about the same value as the mineral industries-each of them thus contributing about one-quarter of our total na-tional income. No other continent has demonstrated its possession of such a magnitude of minerals as has ours, and such a bountiful distribution over our whole land. But our mineral resources differ in one essential from our other natural resources-they are not renewable. Agricul-ture, forests, and water power replenish their supplies from season to season. Some people conclude from the non-renewable character of the mineral supply that they must shortly be exhausted. The practical question is ,one of time, and time in these matters needs to be measured in generations, and apprehension of exhaus-tion needs to be tempered with many probabilities in-cluding the advance in technical methods of extraction. In some of our minerals, such as coal, iron, and building materials we can, through a knowledge of their geologi-cal structure and occurrence, make fairly good estimates of our reserves. We. know that they will outlast many generations of Americans. In non-ferrous metals and oil, geology affords us no great basis for an estimate of future supply. We only know of the occurrence of minerals of this type by actual exposure of them, and we can thus make no estimates except upon reserves which have been proved by actual development by the process of mining. To develop them ahead merely for national satisfaction of assured future supply would imply an unbearable waste of capital. The consequence is that in these groups there is never a demonstrable assurance of more than a few years' supply ahead of us. Yet we have never failed from year to year to find new deposits and extension of old deposits.

Jan 1, 1928

Minerals are a fundamental component of the Nation" material and economic base. Without a continuous supply of minerals to meet growing and changing needs, the basic character of our society would be very different. The importance of minerals to the United States was reemphasized by the Congress in I970 when it enacted the Mining and Minerals Policy Act, which stated that it is the continuing policy of the Federal Government in the national interest to foster and encourage private enterprise in (I) the development of economically sound and stable domestic mining, minerals, metal and mineral reclamation industries, (2) the orderly and economic development of domestic mineral resources, reserves, and reclamation of metals and minerals to help assure satisfaction of industrial, security and environmental needs, (3) mining, mineral, and metallurgical research, including the use and recycling of scrap to promote the wise and efficient use of our natural and reclaimable mineral recources, and (4) the study and development of methods for the disposal, control, and reclamation of mineral waste products, and the reclamation of mined land, so as to lessen any adverse impact of mineral extraction and processing upon the physical environment that may result from mining or mineral activities.,.

Jan 1, 1977