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By Karol Kostúr

This paper briefly describes the current state of underground coal gasification (UCG) processes globally and in the Slovak Republic. Recent results of laboratory and technical tests are presented. In addition, on site measurements have added new knowledge of UCG technology. A series of laboratory tests based on physical models shows promise for managed UCG process control.

Aug 1, 2013

By Thomas J. Snyder

Modern quarry management should be alert to every opportunity to improve productivity and reduce operating costs. In this paper, the author outlines areas in which explosives suppliers should be encouraged to propose changes. He also supplies guidelines for evaluating these proposals, suggests yardsticks for measurement, and stresses the need to be open-minded when dealing with imaginative, innovative concepts.

Jan 1, 1988

Meeting of Nov. 20, 1914.-Charles F. Rand was unanimously elected as the representative of the Institute on the John Fritz Medal Board of Award. E. Gybbon. Spilsbury was unanimously elected to succeed himself in January, 1915, on the Library Board of the United Engineering Society. . The President appointed Messrs. Walter Douglas, Charles E. Mills, and L. D. Ricketts as delegates to the seventeenth National Convention of the American Mining Congress, Phoenix, Ariz., Dec. 7 to 11, 1914. It was voted that the sum of $857.61, or so much of it as may be necessary, be advanced to the Land Fund from the general funds of the Institute, in anticipation of the collection of unpaid installments of subscriptions to the Land Fund; and that the Treasurer be instructed to pay to Andrew Carnegie at the present. time the sum of $2,500 on account of the Land Fund indebtedness.

Jan 1, 1915

By H. M. von Seebach, M. P. Trubeljal, L. G. Austin

Six US coals and a crystalline quartz were tested in an instrumented laboratory high-pressure grinding rolls machine equipped with 100-mm-diam. rolls. The machine was choke-fed to maximize the capacity. As expected, the specific capacity decreased with increased grinding pressure for each material tested. Among the six coals, there were significant differences in the critical angle of nip, the effective feed porosity and the variation of strain at the gap relative to the grinding pressure. Although a precise correlation was not obtained, the overall effect of these factors was that, at a given grinding pressure, the specific capacity increased as the Hardgrove grindability index of the coal increased. The relationship between the specific capacity and the grinding pressure for a given coal was independent of feed size down to 150 µm. However, smaller feed sizes produced anomalous results, and the flow within the feed hopper was restricted.

Jan 1, 1996

By Charles L. Kimbell

Tables 16 through 19 continue the series of providing the world merchant fleet distribution by type of vessel and the ranking of the major fleets by country of registry. Table 20 this year provides a summary of the world's liquid gas carrier fleet. These vessels are included in the totals given for the world's tanker fleet, but gives a breakdown demonstrating the growth of the importance of natural gas in the world's energy commodity consumption. Panama and Suez Canals Tables 21 and 22 provide the latest available information on the transit of mineral commodities through the Panama Canal, by number of vessels, direction, and the commodities transported. Although the number of vessels transiting the Panama Canal dropped slightly (0.5%) between 1989 and 1990, the total amount of cargo moved rose by 3.6% and the amount of mineral commodities moved rose by 7.2%.

Jan 1, 1993

By Raúl Veramendi

Ante la existencia de un número de zonas inestables y de magnitudes proporcionalmente grandes en las operaciones de minado, se requería de un monitoreo continuo en tiempo real que genere información confiable con exactitud y precisión referente al comportamiento crítico de los taludes para luego evaluar, alertar anticipadamente los colapsos y evacuar de forma segura y oportuna al personal y equipos. En ese sentido, el presente texto describe el mejoramiento del monitoreo de taludes a través del uso de radares donde se pudo identificar zonas críticas de desplazamiento de taludes con el fin de mejorar la seguridad del personal, equipos y garantizar la continuidad de las operaciones para asegurar el cumplimiento de los programas de producción de la Mina Cuajone.

Sep 21, 2013

By Paul K. Krueger

SUMMARY Since 1970 the Federal Preparedness Agency has been using computer models to help establish the amounts of strategic and critical materials to be held in the National Stockpile. Fifty-three of these materials are metals or minerals. The following diagram shows the linkage of models used to estimate material requirements. [ ] The starting point for the models are estimates of the major components of GNP for some future period. These may be estimates purchased from a forecasting service or may be produced in-house. The projections are translated into industrial final demands using DITT (Demand Impact Transformation Tables), a system developed at FPA. Then using a version of the current Bureau of Economic Analysis input-output model, estimates are made of the gross output of each industry necessary to support the level and composition of GNP as specified by the macro-economic model.

Jan 1, 1977

By Jorge Bombilla Delgado

El presente texto señala la descripción de técnicas de voladura en Cerro Verde a partir de la descripción de la geología del área mineralizada de dicho asentamiento minero. Posteriormente se describe los dos principales sistema de estructuras: uno con rumbo general noroeste -sureste y el otro sistema con rumbo noreste-suroeste, donde se produce un fracturamiento, cuya importancia radica en la ubicación y la orientación de salida que se de al disparo. Asimismo se describe los explosivos utilizados, la sensiblidad de los mismos, la preparación del ANFO, los métodos de trabajo, disparo, el diseño de perforación y las cargas explosivas.

Nov 20, 1978

The Pennsylvania State College, Mineral Industries Experiment Station, State College, Pa For publications address the Director The Pennsylvania State College through the Minerals Research Experiment Station has issued 10 Bulletins and three Technical Papers, from which the following have been selected as of greatest interest to mining engineers and geologists: Bulletin 1, An investigation of the properties of smitliing coals (1922), free; 2, Petrography of the Mica Pendotite Dike at Dixonville (1926), free; 4, The Helderberg Group from cen¬tral Pennsylvania to southwestern Virginia (1929), 25 cents, 5, Bentonite in Pennsylvania (1929), 10 cents, 6, Production data on Appalachian oil fields (1930), free; 8, Oil field waters of Pennsyl¬vania (1930), free; Technical Paper 2, Condition of water in coals of various ranks.

Jan 1, 1933

By E. Paransky, M. Rigaud, G. Paschek, S. Palco

Some of the negative impacts of carbon addition on the strength of castables are yet to be overcome in order to fulfill its potential benefits for oxidation resistance. This paper reports the results of recent studies conducted at CIREP on the effects of different types of carbon additives on the thermo-mechanical properties of magnesia-based castables. Experimental techniques included measurements of the hot modulus of rupture (HMOR), hot modulus of elasticity (HMOE), as well as the wedge-splitting test (WST). The comparison of evolving microstructures was carried out employing scanning electron microscopy with microanalysis attachment (SEM/EDS) and X-ray diffraction (XRD). HMOR values of 12 MPa at 1300°C have been reached in MgO-Si02-C castables containing up to 7% carbon.

Jan 1, 2004

By C. Allen, A. Roy, J. W. Evans

A spouted bed electrode (SBE) has been used, in laboratory experiments, to electrowin zinc from zinc chloride electrolytes with the objective of determining the suitability of this electrode for commercial application. Zinc was successfully electrowon at current densities ranging up to 4,38 lA/m2, which are an order of magnitude larger than those used at present in the zinc industry. Current efficiencies, for the cell with the SBE, have been as high as 90% and DC energy consumption as low as 2.8 kWh/kg zinc deposited. The performance of the cell has been measured as a function of current density, anode type, cell diaphragm, addition of tributyl ammonium chloride and purging of the electrolyte (to remove dissolved chlorine).

Jan 1, 2000

By Earl A. Gulbransen, Kenneth F. Andrew

DRY oxidation of zirconium has been studied by several groups.'" The present work extends our early study1 to the high-temperature studies of Cubicciotti2 and Belle and Mallett.8 ulbransen and Andrew1 showed that the parabolic rate law fitted the 2-hr experiments between 200" and 425°C after an initial deviation. An energy of activation of 18,200 cal per mol was calculated. Cubicciotti,' in a study between 593" and 880°C, showed that the parabolic rate law fitted the data and an energy of activation of 32,000 cal per mol was calculated. In contrast to these studies on sheet specimens, Belle and Mallett3 studied the oxidation reaction on rod specimens and found a cubic rate law to fit the data.

Jan 1, 1958

By Jeff Wachendorf

As the title "Cast Blasting Around Town" implies, this paper details the starting of a cast blasting program in and around the town of Colstrip, Montana. As strip ratios have increased, the need to adapt and find solutions to provide coal at a reasonable cost to the captive power plants has risen. Colstrip, Montana has a long history of coal mining which dates back to the early 1920's when Foley Brothers began supplying coal strictly for powering locomotive engines. Early mining days starting in the 1920's and the progression up through the 1970's when mine mouth power plants were built will be discussed. To accomplish the desired results, early mining techniques included steam and electric powered equipment as well as a lot of actual horse power.

Jan 1, 2009

By Marvin P. Barnes

The Sacaton open pit copper mine has recently been placed into production. Some problems have been encountered in maintaining grade control due to differences between early block estimates and actual production grade. A study was made using three methods for computing grade for 50' x 50' x 40' size blocks from exploration and development drill holes; 1) The polygonal method, 2) The inverse distance squared method, and 3) The geostatistical kriging method. The results of each were compared against a control block file created by using the assay results of all blast holes drilled in the ore over three benches of the new pit. Results indicate that the kriging technique gave better estimates for grade of individual blocks than did the other two methods for this particular deposit.

Jan 1, 1977

By T. S. Maio, J. G. Mansanti

In 1978, Ozark Lead Co. made the decision to expand the capacity of its mine/mill complex by 33%. The objectives of the expansion were to increase mine production capacity by 1.8 kt/d (2000 stpd), increase lead metal production by 21.8 kt/a (24,000 stpy), and to construct new facilities and modify existing equipment to accommodate increased production. This paper gives a brief explanation of the equipment installed and the overall production and metallurgical benefits realized from this expansion. The expansion was completed in the second half of 1980 with all equipment debugging and fine tuning completed by the first quarter of 1981. Concentrator modifications and improvements were basically restricted to four areas: materials handling, automation of the mill grinding circuit, increased flotation capacity, and concentrate dewatering.

Jan 1, 1985

I am interested in experiences people have had with blasting near existing railroad tracks: What kind of vibration criteria are used, and how successful you have been in gaining approval for blasting in the vicinity of railroads. This would both be for passenger and freight railroads

Jan 1, 2008

By William C. Cooley

Modern tunnel boring machines are subject to excessive cutter wear and bearing failures when used in hard and abrasive rock. In very hard rock, the high cost of cutter and bearing replacement, combined with slower excavation progress, make it more economical to drive tunnels by conventional drill and blast methods. The use of high pressure water jets to break rock provides a promising alternative. Experimental data indicate that the specific energy (the energy expended per unit volume of rock broken) decreases as the water jet pressure increases. Continuous jets are generally limited to pressures below 100,000 psi, whereas pulsed jets from a water cannon can attain much higher pressures. Therefore, the Federal Railroad Administration of the U. S. Department of Transportation has sponsored the design (Ref. 1 & 2) and the fabrication and testing (Ref. 3 & 4) of a water cannon to determine its effectiveness in rock disintegration at very high pressures. This paper reports the results of laboratory tests with pulsed jets against large rock samples at pressures of 125,000 to 650,000 psi and field tests against dolomitic limestone and granitic gneiss at pressures near 450,000 psi. Although initial tests were made with a small nozzle, operating at off-design conditions (Ref. 4), this paper only covers results with the full-size nozzle, including 55 laboratory test shots and 67 field test shots.

Jan 1, 1974

The personnel of the Committees of the Institute and its representatives on the various society and national committees will be found in the Year Book.

Jan 7, 1919

PENNSYLVANIA ANTHRACITE LOCAL SECTION On Saturday evening, Jan. 31, 1914, about 40 members of the Institute met at the Hotel Sterling, Wilkes Barre, Pa., for the purpose of discussing plans for the formation of a local section in the Pennsylvania anthracite region. President Rand; Prof. Joseph W. Richards, of the Board of Directors; Dr. H. M. Chance, Chairman of the Committee on Coal and Coke, and Secretary Stoughton were among the guests present. R. V. Norris acted as Master of Ceremonies, and the arrangements were all made in advance by a Committee under the leadership of Charles Enzian, to whom an enthusiastic vote of thanks was accorded at the dinner. An address was made by President Rand, followed by .Professor Richards, who outlined the procedure necessary for the formation of a Local Section. Addresses were then made by W. J. Richards, F. W. Chase,. C. F. Huber, R. J. Foster, F. A. Hill, H. M. Chance, Bradley Stoughton, and others, after which a rising vote was taken, and it was unanimously decided to petition the Board of. Directors for the establishment of the Pennsylvania -Anthracite Local Section. More than the required number of members then signed -the petition, and President Rand announced the appointment of a Committee to organize the Section and arrange for a meeting in accordance with their By-Laws, consisting of R. V. Norris, W. J. Richards, R. J. Foster, Edwin Ludlow, C. F. Huber, Charles Enzian, Douglas Bunting, F. A. Hill, and J. M. Humphrey.

Jan 2, 1914

President Robert M. von Storch, General Superintendent, Coal Mines and Quarries, Columbia-Geneva Steel Division, United States Steel Corporation, Dragerton, Utah, called the meeting to order at 9:30 a.m. in the absence of John Peperakis, Past President, who was usable to attend because of a mine fire. He welcomed the members with a paper entitled "With Serene Confidence." He also showed a short movie, "The Waiting Harvest," with his speech. Following the president's speech, the first business meeting of the Institute was held. Secretary-Treasurer Fred Whiteside presented the Treasurer's Report. Motion made by Mr. Whiteside, second by Stan Shubart that this report be accepted. Motion carried. Because the minutes of the last meeting were published in the Institute's booklet, the reading of the minutes was dispensed with, and the President announced the members of the various committees: General Chairman ? Charles M. Schloss

Jan 1, 1958