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By J. W. Thompson

"The Republic of Colombia on December 30, 1919, enacted a new petroleum law. The Act is expressly limited to mineral oil, natural gas, bitumen, wax and fossilized resin and to asphalt intended for export.The law is not only intended to encourage local investors, but to attract foreign capitalists for oil development. Provision is made for a special edition ion of the law in such languages as the Government may deem necessary to give it extensive circulation within the country and abroad. The published editions must contain the provisions of the law relating to alienship and naturalization.All public lands, or what are termed unclaimed lands, are open to flee prospecting for the purpose of discovering the deposits named in the law, A prospector must obtain from the Government a, license which binds him to deliver to the Government topographic plans of the lands prospected, together with reports of their prospective yielding capacity. This license does not vest the li¬censee with any preferential right for contracting or leasing and may be drawn by the Government at any time.If a discovery is made by a licensee of any of the deposits named and he desires to exploit the same, he must present a memorial or application to the Ministry of Public Works, stating:- (a) the location and municipal district in which deposit beds are found; (b) boundaries of the zone of exploitation, which shall not be more than 5,000 or less than 1,000 hectares; (c) the names and nationality of all persons for whom the lease is sought and the action and time within which,they propose to make the exploitation; (d) the name of the corporation and its legal representatives with their residences; (e) if an alien, he must state his willingness to comply with the law relative to alienship and naturalization; (f) agreement to abide by all of the provieions of the law with regard to Government supervision, payment of taxes, rate of lease and causes of forfeiture; (g) the rate of rent or royalty that the applicant offers to pay, together with any other circumstances that may make the proposed lease advantageous to the Nation."

Apr 1, 1920

By J. N. Van der Merwe, D. P. Roberts

The two components of pillar design formula being used in South Africa are pillar strength and pillar load. While considerable effort has been directed to the determination of pillar strength, the other half of the safety factor equation, the load, has not received the same amount of attention. The load acting on pillars has always been calculated using the Tributary Area Theory (TAT). This paper summarises the recent studies on coal pillar loading using various numerical models. It concludes that although there are meaningful differences under certain circumstances, there is still a compelling argument to use the TAT in coal pillar design. Les deux parties composantes de la formule de conception de pilier généralement utilisée en Afrique du Sud sont la résistance de pilier et la charge de pilier. Tandis que des efforts considérables on été dirigés vers la détermination de la résistance de pilier, l’autre moitié du facteur de sécurité n’a pas reçu la même attention. La charge agissant sur les piliers a toujours été calculée avec la Théorie d’Aire Tributaire (TAT). L’étude présente résume les études récentes sur la charge de pilier de charbon utilisant des modèles numériques variés. La conclusion est que bien qu’il y ait des différences significatives selon les circonstances, il y a toujours un argument puissant pour utiliser le TAT dans la conception de pilier de charbon. Die in Südafrika für die Auslegung von Pfeilern verwendeten zwei Formelkomponenten sind Pfeilerstärke und Pfeilerbelastung. Während beträchtlicher Aufwand zur Bestimmung der Pfeilerstärke gemacht wurde, wurde der anderen Hälfte der Sicherheitsfaktorsgleichung nicht die gleiche Aufmerksamkeit gewidmet. Die auf die Pfeiler wirkende Last wurde immer unter Verwendung der Tributary Area Theory (TAT) berechnet. Diese Arbeit fast neuere Studien betreffend der Belastung von Kohlepfeilern unter Verwendung verschiedener numerischer Modelle zusammen. Die Schlussfolderung ist, daß obwohl unter bestimmten Vorraussetzungen bedeutende Unterschiede existieren, nach wie vor ein bezwingendes Argument besteht TAT in der Kohlepfeilerauslegung zu verwenden.

Jan 1, 2003

This report provides concepts for two automated longwall mining systems; one for operation in a 42 to 57-inch thick section of the Lower Kittanning coal seam, the other in a 57 to 72-inch thick section of the Pittsburgh seam. The Lower Kittanning concept uses a single-drum bidirectional shearer and 500-ton capacity 4-leg chocks and the Pittsburgh concept uses a double-drum shearer with 500-ton shields. Each concept is designed to produce in excess of 2,500 tons of clean coal per shift with a 6-man face crew. The automated longwalls consist of off-the-shelf control system hardware attached to standard longwall equipment. Control hardware includes a control and display console; prime and backup mini-computers; multiplex data transmission, power, and control lines; several remote terminals which serve as interface junctions; and various sensors and actuators located on the longwall equipment. The system can be operated either fully automatically, remotely or manually.

Jan 1, 1976

Since the introduction of water cooled test rings the operation of cupelling retort bullion has not alone been sImplified, but has also been the means of concentrating the bullion for the fining test in a much shorter time.The first water cooled test ring which I used was rectangular in shape, inside dimensions 5 ft. 3 in. x 2 ft. IQ in., and made of i in. mild steel plates, with a water space of 9i in. x 3t in. However, it was found that as soon as the filling commenced to wear and the litharge came in contact with the jacket, the plate was gradually affected on the lines of the wash, caused by the blast. After a while the inside steel plate went beyond the factor of safety, and was then substituted on the sides and the front of the test ring by a tin copper plate, which has stood now for the last five years without showing the least signs of wear or leakage.The test remains in use as long as the bottom is regarded as safe, and toward the end of the life of the test the litharge is allowed to work against the copper plate.

Jan 1, 1901

By P. Rambalee

A multiple coal fired boiler house provides steam for utility usage in various production plants. Maintaining stable header pressure and boiler availability is of critical importance for downstream consumers. Advanced Process Control comprising of a G2 based expert system and Model Predictive Control was implemented to improve the boiler house performance. The results yielded improvements in the main header pressure stability, reduction in boiler saturation and significant saving in coal consumption. All information used for this document is from a published whitepaper written and led by Prevlen Rambalee (Anglo Platinum) and Gustaf Gous (BluESP) titled, ?Control and Stabilization of a Multiple Boiler Plant: An APC Approach?.

Jan 1, 2012

By Juan Mendoza Marsano

"El presente texto revela las primeras transacciones de la venta del oro en el Perú -en tanto se determina su precio a través de un acuerdo denominado""on the spot"", donde el vendedor ofrece sus mercaderías a uncomprador y se acuerda un precio pagado con dinero al contado y de inmediato. Hasta 1914 el precio del oro estuvo determinado o fijado por la denominación de las propias monedas circulantes de oro y sus monedas equi- valentes. Sin embargo, la primera determinación del oro en el Perú surge en Cajamarca, 1553. Posteriormente se describe la circulación de este durante la Colonia, los diferentes métodos de transacción y las especificaciones del contratos de oro, así como los factores que influyen en el precio del oro."

Nov 1, 1978

The U.S. economy continued to expand during 1986, although at the slowest pace since 1982 when the current business expansion began. Real gross national product (GNP) grew about 2.6%, slightly below 1985 growth but significantly below that of 1984. The continuing expansion was fueled predominantly by rising personal consumption expenditures as well as growing government purchases of goods and services. Fixed investment, although positive, failed to grow at the rate of the overall economy. The trade deficit, which increased more than 30% over the record 1985 level, continued to depress economic growth despite significant declines in the price of petroleum and the value of the dollar. On a more positive note, domestic employment continued to grow--increasing over 2 million from the 1985 level--and inflation and interest rates declined. The unemployment rate dropped slightly to 7.0%. Of direct importance to the minerals-producing industries, expenditures for consumer and producer durables as well as investment in residential construction each grew faster than the overall economy, but investment in nonresidential structures fell more than 10% from the 1985 level. The low level of real capital spending declined about 3% in 1986, following strong gains in 1985 and in 1984. Capital expenditures for new plant and equipment bottomed out in the second quarter and expanded in the third and fourth quarters. The decline in the first half of the year was partially attributed to uncertainty arising from the then-proposed tax bill. Also, there was little impetus for corporations to invest in new capacity since factories were operating at less than 80% of capacity during most of the year, in part because of continued competition from imports.

Jan 1, 1987

By Paul M. Tyler

MUCH has been said in print, and much more that was unprintable, about burdensome controls, taxation, and multiplying restrictive, regulatory, or taxing activities of the Federal Government, but not so much has been said about ways and means whereby the Government can and does render economic assistance. Economics has been defined as the study of men earning a living, and economic assistance to industry as well as to individuals properly should take the form of helping enterprisers to help themselves rather than charity. Proposals to have the Government play Santa Claus must be examined carefully if -only to avoid undue favoritism to politically important persons and downright venality by potentially crooked public officials. Thomas Jefferson is credited with the remark that the best government is the one which governs least. Paternalism is abhorrent to most Americans.

Jan 1, 1947

By N. Akbulut, A. Anani

From the initial planning phases to the closing of a mine, mining is an industry where high attention, care, and sensitivity are needed in every step of the mine life. Since mining projects have a long-life span, exceeding a decade sometimes, managing a whole mine project is challenging, especially when challenges faced due to generational differences are considered, such as tracking and logging data, or the usage of different engineering solutions change over time. Along with the overall hardship caused by the time put into a mining project, the present-time operations are very costly where each minute counts. In present-time operations, every decision made, and every minute used during planning and operations has an impact on the efficiency, safety, and economics of the project. Having extremely harsh conditions in both the excavation and mineral processing operations not only slows down the processes but creates very dangerous environments that need to be handled with precise safety measurements. To support the already established processes, we could implement new technologies and use them to our advantage. Virtual reality (VR) is one of these technologies that we could implement in the mining industry. VR is a technology that emerged in the 1960s creating virtual environments and platforms. The user experiences these virtual environments from head- mounted headsets to rooms with 360 screens, all with different levels of immersion. These higher levels of immersion, create a higher level of presencemaking the users more engaged in the activity they are trying to accomplish. These two factors of immersion and presence are what make VR unique and beneficial. VR has some applications and case studies in the industry along with some research being conducted in universities. Unfortunately, there has not been a comprehensive literature review or analysis regarding only VR and its implementations for the mining industry in the last 5 years. This paper aims to describe what VR is and its relation to the mining industry, in the most recent years. The paper first gives a brief background on what VR is and its key concepts. Secondly, it will give information on how the initial stages of the literature review were conducted and the findings along with discussions. The paper will finish with the conclusion drawn from the discussion and potential future work.

Feb 1, 2023

By M. C. Harris

The past twenty to thirty years have seen unprecedented research activity aimed at understanding the performance of flotation froths. In 1990, Finch and Dobby coined the term froth recovery factor, Rr, to represent the efficiency of the froth in delivering particles from the pulp-froth interface to the concentrate. Originally defined for flotation columns, Rr has also been found useful in modeling mechanical flotation cells, and a number of techniques, based on quite different approaches, have been developed for measuring the froth recovery in industrial flotation cells. None of these techniques is universally successful. This paper reviews the concept of the froth recovery factor, and the basis of each of the techniques that have been proposed to measure Rr, and examines the reasons for this parameter being so difficult to pin down. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By Judy K. Todd

Double benching has been utilized as an excavation technique in open pit mines for many years. This process involves drilling, blasting, and excavating the material for the design bench height. A second bench is then excavated without the creation of a catch bench, i.e. only minimal offset from the first bench face is allowed when drilling off the second bench. The result is a double high bench face or double bench. When drilling off the second bench, the offset of the drill from the bench face projects the lower bench face into the pit up to an extra five meters. This reduces the maximum attainable bench angle, enhances the probability of rock escaping the catch bench and increases the overall strip ratio. The generally utilized process of trim blasting also can impact on the final bench profile by contributing to blast damage of the face. BHP Billiton Diamonds Inc., Ekati Mine Diamond MineTM, has pioneered the usage of a technique that eliminates this offset. Double benching is accomplished by drilling a single, 30m pre-shear (two 15m benches) to define and protect the final bench profile. This article provides a comparison of the attained face angles obtained in the field utilizing both of the above methods, as well as a comparison with the analytically predicted angles prior to excavation.

May 1, 2002

By Walter K. Utt

The process of drilling and bolting the roof is currently one of the most dangerous jobs in underground mining, resulting in about 1,000 accidents with injuries each year in the United States. To increase the safety of underground miners, researchers froth the Spokane Research Laboratory of- the National Institute for Occupational Safety and Health are applying neural network technology to rite classification of mine roof strata in terms of relative strength. In this project, the feasibility of using a monitoring system on a roof drill to assess the integrity of a mine roof and warn a roof drill operator when a weak layer is encountered is being studied. Using measurements taken while a layer is being drilled, one can convert the data to suitably scaled features and classify the strength of the layer with a neural network. The feasibility of using a drill monitoring system to estimate the strength of successive layers of rock was demonstrated in the laboratory.

By George S. Rice

The major purpose of this bulletin, as indicated in the preface by Dr. John W. Finch, Director of the Bureau of Mines, is to give a critical review of the coal-mining methods used in the principal producing countries of Europe, to describe the reasons underlying the adoption of these methods, and to contrast them with coal-mining methods employed in the United States. The report includes discussions of various subjects intimately related to coal mining, such as geology of the principal coal fields; production and resources of the several countries; mine safety and health research; Government mining regulations; mine inspection and rescue procedure; safety lamps; fixed lighting methods under-ground; testing electric motors, mining machines, and mining explosives for permissibility; and special mining hazards, such as explosions of gas and coal dust, mine fires, instantaneous gas outbursts, ground movement and surface subsidence, and bumps. Commercial, economic, and labor problems of European coal mining, including miners' output, wages, and social-insurance schemes, as well as cost of mining, prices of coal, etc., are briefly described. It will be noted that data on most subjects are not given for Russia, which has become an important coal-producing country, owing to the lack of reliable published information concerning Russian coal mining.

Jan 1, 1939

By S. L. Windes

This report presents a tabulation of the physical and petrographic properties of Over 100 rock types from operating mines or mineral-investigation projects. The physical properties include the following: Apparent specific gravity Apparent porosity Compressive strength Flexural strength, (modulus of, rupture) Impact toughness Abrasive hardness Scleroscope hardness Modulus of elasticity (Young's modulus) Modulus of rigidity Specific damping capacity Longitudinal bar velocity

Jan 1, 1949

By Shigeru Tsutsumi

The rapid development of transportation facilities in Japan focused the attention of this country on the possibility of converting the existing coal resources (of which there was an abundance) into liquid fuels, for which there was a constantly increasing demand. Previous work had indicated that this could be accomplished by utilizing one of two processes - the Bergius process, in which high temperatures and high pressures were employed to effect direct liquefaction of the coal, and the Fischer-Tropsch process, in which an indirect liquefaction of coal was accomplished by the production of liquid hydro-carbons from hydrogen-carbon monoxide mixtures. This report describes some investigations into the latter process, which was first developed by Fischer and his colleagues in the Coal Laboratory in Muhlheim, Germany, in 1923. By 1932, these investigators had achieved a 60-percent theoretical yield (152 ml. of liquid hydrocarbons per cubic meter of 2H2:ICO synthesis gas) by using a precipitated Co-Th02 catalyst.3/ At the same time (1932), Dr. Kita of Kyoto Imperial University and Messrs. Fujimura and Tsuneoka obtained 145 ml. of gasoline (C5+) per cubic meter of synthetic gas by using a Co-Cu-Th-U catalyst. 4/ This report is a description of the experimental results subsequently obtained at the Fuel Research Institute, Kawaguchi City, Saitama, up to 1935.

Jan 1, 1951

By Jiongtian Liu, Guihong Han, Shuzhen Yang, Yanfang Huang

Binder, as a necessary functional material of electrode in lithium ion battery, has a vital influence on the electrochemical performance. The humics, coupled with polyacrylamide (PAM) and sodium carboxymethyl cellulose (CMC), were used as a water-soluble binder for LiFePO4 (LFP) cathode using in lithium ion battery. The techniques of cyclic voltammetry (CV) and galvanostatic charge-discharge were conducted to evaluate the performance of humics binder in LFP electrode. The reversible specific capacity of LFP (HA + PAM + CMC) electrode can reach to 142 mAh g−1 after 50th cycling (100 mAh g−1) on conditions of raw materials with 1 wt% PAM addition, humics and CMC with a mass ratio of 3:1 in binder, and the raw materials mixed in an interval order. Humics has the potential to be used as a novel, eco-friendly and high-efficient binder for lithium-ion battery.

Mar 1, 2018

By N. R. Paterson, D. G. MacKay

"The geology of the Mattagami mining camp, while of particular economic significance, is unfortunately obscured by a very thick mantle of overburden. For this reason geo-physical methods have been relied upon heavily in exploring the area. Geophysical data over five important sulphide discoveries show how targets are selected for drilling and how effective geophysics has been in assisting subsequent development programs."

Jan 1, 1960

By R. Dewey

WHAT IS AI? It's very hard to say. Most researchers and practitioners disagree with nearly any attempted definition, but most would agree that A1 does deal with the development of computer-related methods o f problem-solving. Artificial intelligence is a discipline which seeks to emulate human anatomy and/or thought processes by applying computer science, electronics, and mechanical engineering to the development of natural language processing, machine vision, robotics, and knowledge-based expert systems. Integration of these four fields will someday produce the robots of today's science fiction. A1 addresses problems of structuring large amounts of knowledge and representing relationships with rules and semantic frameworks rather than with mathematical equations. A1 is convergent rather than divergent - - conventional conputer applications use relatively small quantities of input to generate large output, but A1 generally reduces large amounts of information to establish a few major conclusions. The development of A1 has prompted greatly increased efforts on the part of scientists and engineers to understand just how humans think, organize information, approach problem-solving, and form conclusions. Some of the more exciting and possibly far-reaching advances in A1 are coming in this more-or-less soft-science area. Thirty years of A1 research (dating from a 1956 conference at Dartmouth College at which the term A1 was coined) has already spawned many widespread, almost ordinary, products: window graphics, hand-held controllers (mouse). function menus, etc., all in an attempt to make computers and people more compatible. WHAT IS AN ES? A1 can be used to develop EXPERT SYSTEMS, which are computer programs or systems which contain knowledge and rules by which problems can be solved. or at least by which possible solutions can be suggested for very complex problems. A1 can be used to better define problems so that solutions can be found. An ES is designed not to process numbers, but to process information according to rules and logic derived from actual practice and experience. WHY AI? WHY ES? Companies are increasingly aware of the value of accumulated knowledge and experience in designing, building, operating, and maintaining the increasingly complex or expensive physical plants in any business. As knowledge branches out and becomes more specialized, the accumulated learning of a veteran operator or manager or engineer becomes a scarce resource well worth preserving. EXPERT SYSTEMS offer a means of doing that, reinforcing, not replacing, human capabilities.

Jan 1, 1987

By E. E. White

(Cleveland Meeting, October, 1912.) IN, August, 1911, I read a paper before the Lake Superior Mining Institute' on surveying and sampling diamond-drill holes. The present paper gives a more thorough description of these methods, together with a few changes and notes suggested by further experience. Since August, 1911, the methods, used constantly by the Cleveland-Cliffs Iron Co., have been developed to a higher degree of efficiency, and have given great satisfaction. Until a few years ago but little attention was paid to the determination of the actual course of drill-holes, to the accurate sampling and analysis of the material, or to the scientific location of the drill-holes. It has now been common practice for several years in many districts to test the inclination of drill-holes by etching glass tubes with hydrofluoric acid, but the direction of deviation from the vertical has not often been determined. Methods of determining the direction by means of a compass were first developed in connection with drilling in Victoria. The latest method used on the Rand in South Africa has been recently described by John I. Hoffman.2 In the same paper Mr. Hoffman describes an ingenious method of wedging-off a drill-bole so as to start new holes at several successive points. By this means a hole can be deflected in any desired direction, and the curvature can be controlled to a considerable extent, provided the rock is soft enough to permit the hole to be wedged off. Unfortunately, in the Lake Superior district, the jasper iron-formation is so hard that it is very difficult, if not impossible, to do this. I tried to deflect one hole so as to avoid drill-rods stuck in the hole, by using a 1 Proceedings of the Lake Superior Mining Institute, vol. xvi., pp. 100 to 120 (1911). 2 Recent Practice in Diamond-Drilling and Borehole Surveying, Bulletin No. 91, Institution of Mining and Metallurgy (Apr.. 11, 1912).

Nov 1, 1912

This: symposium was sponsored by the Bureau of Mines, U.S. Department of the lnterior, in order to critically examine the state-of-the-art of sulfide flotation chemistry and to define current and emerging problems that should be emphasized in future fundamental research. The topics covered through invited papers include both reviews and recent research results in the areas of thermodynamics of reagent-mineral interactions; collector adsorption processes; the effects of solid-state point defects on flotation; activation and deactivation phenomena; the electrochemical role of oxygen in sulfide flotation; environmental problems in flotation; and selective flocculation of fines. Papers riving perspectives on flotation research in relationship to our national mineral requirements and the relationships between industrial flotation research and academics are also presented. An edited summary of the symposium follows the papers.

Jan 1, 1980