Search Documents

By X. B. Wang, Z. Q. Guo

Slagging coal gasification process became a highlight of coal chemical industry in China during the last decade. Refractory lining's life of slagging gasifiers is one of the most critical factors for a cost-effective operation. The paper introduces current status of coal gasification in China, lining structure of slagging gasifiers and performance of refractory lining. It also summarizes the major factors impacting on refractory wear in slagging coal gasifiers in four Chinese chemical plants, based on ten years of industrial experience. The utilizability is discussed in terms of cost-effectiveness of high chromia refractories and possibility of the alternatives.

Jan 1, 2004

By P. Zhang

The Crago “Double Float” process is widely used in upgrading phosphate ore. This process is inefficient, as it floats about 30-40% of the sands in the flotation feed twice and requires a deoiling step. This paper summarizes several research projects on improving phosphate flotation. The University of Utah investigated a new flotation chemistry for efficient flotation of phosphate in a single step. The Florida Institute of Phosphate Research developed several single-collector, all-anionic flotation flowsheets using various sizing schemes. In addition, Eriez invented the HydroFloat separator, which demonstrated great potential for processing coarse flotation feed in one step.

Jan 1, 2004

Uranium, the object of a quarter billion-dollar search in the US during 1977, is a ubiquitous element rarely found in economic concentrations. It originates in magmas as a large tetravalent ion, the size of which restricts it from the crystal lattices of many rockforming minerals. Instead, according to United States Mineral Resources (US Geological Survey Professional Paper 820) as the magma crystallizes, a portion of the uranium is deposited as an intergranular film on rock forming minerals, enters accessory minerals, or forms its own minerals. The remaining uranium becomes concentrated in magmatic differentiates, where it forms minerals in pegmatites and veins.

Jan 10, 1978

By N. J. Themelis

What is the "best" copper smelting technology? When a future Agricola examines the development of copper smelting in the 20th century, he will be amazed at how little took place in the first half of the century and how much in the second. In a period when the technology of transportation, communications and chemical processing advanced many fold, copper smelting remained practically static. The result of tightening energy supplies and stringent environmental controls in recent years has been a spate of development activity that not only is challenging the supremacy of the reverberatory furnace, but threatens to wipe out pyrometallurgical techniques entirely.

Jan 1, 1976

By H. Habenicht, E. Urschitz

Three mining methods for full extraction in flat coal seams - i.e., longwall (L W), shortwall (SW), and rib pillar extraction (RPE) - are com- pared with each other in view of the introduction of a mechanized, self-advancing roof support. Features are shown according to which RPE appears most attractive under certain conditions. In this presentation, the mining methods are outlined and discussed. The new support (Alpine Breaker Line Support, ABLS) is described, and its employment is explained. A trial operation in RPE using the ABLS has been conducted successfully in a South African coal mine. The results and improvements are stated.

Jan 1, 1988

New Journals The following three journals may be of interest to readers: Fuel Processing Technology, Process Economics International, Speculations in Science and Technology, MM reports Report no. 2016 Analysis of the NIMROC reference samples for majorelements. Report no. 2018 Supergene aUeration of sulphide ores. II. The effect on the floatability of chalcopyrite, galena, and sphalerite. Report no. 2013 List of unrestricted NI M publications issued from 1966 to 1979. Report no. 2014 The determination by spark-source mass spectrometry, of chlorine and phosphorus in high-purity tungstic oxide. Report no. 2017 Vanadium-bearing titaniferous iron ores from the Rooiwater, Usushwana, Mambula, Kaffirskraal, and Trompsburg Igneous Complexes. Report no. 2022 The determination of thallium and indium in sulphide concentrates. Report no. 2023 Atomic-absorption spectrophotometry with hydride generation: an improved technique. Proceedings Proceedings of the Eleventh Commonwealth Mining and Metallurgical Congress, Hong Kong, 1978. London, Institution of Mining and Metallurgy, 1979. 800 pp. 35,00 or $U.S.77,00.

Jan 1, 1979

[Page Officers of the Institute 5 Minutes of Twenty-first Meeting 9 The U. S. Fuel Company's Tipple at the Hiawatha Mine John M. Jennings 11 Some Experiences With Mechanical Loading in Central Pennsylvania¬ O. G. Sharrer 13 Mechanical Loading Underground- A. W. Dickinson 25 Operation by Long-Face Conveyor Method at Sweetwater Mine Glen A. Knox 39 Discussion of Mechanical Loading 44 Discussion-Safety in Mechanical Loading 45 New Steel Tipple, Spring Canyon, Utah- G. A. Murphy 46 A Theory on the Cause of Spontaneous Combustion-C. P. Crawford... 48 Rock Dusting in the West-D. Harrington 50 Mudite-L. C. Clare 57 Discussion of Harrington's and Clare's Papers 59 Material for Rock Dust-Prepared Discussion-Edward K. Judd 60 Tipple and Mine of the Columbia Steel Corporation-T. C. Harvey 63 Mechanical Stoking of Domestic Fuel-Joseph Harrington 67 The Garrison Automatic Domestic Stoker-Lloyd Garrison 70 Discussion of Domestic Stokers 71]

Jan 1, 1925

NEW YORK LOCAL SECTION Executive Committee Louis D. HUNTOON, Chairman ARTHUR S. DWIGHT, Vice-Chairman THOMAS T. READ, Secretary, Woolworth Bldg., New York, N. Y. E. MALTBY SHIPP, Treasurer GEORGE F. KUNZ W. DE L. BENEDICT Meeting, Jan. 16, .1914 A meeting of the New York Local Section of the American Institute of Mining Engineers was held at the Engineering Societies Building, 29 West 39th Street, New York City, Jan 16 1914 the Chairman, -L. D. Huntoon, presiding. Forty members weld present. In the absence of the Secretary, C. A. Bohn was appointed Secretary pro teen. N. H. Darton, Geologist of the U. S. Geological Survey, delivered an address on. The Occurrence of Gas in Coal, illustrated by lantern slides of charts, curves, and tables showing various features of gas occurrences. J. W. Richards, J. T. Beard, W. L. Saunders, L. D. Huntoon, and Mr. Darton participated in the discussion which followed the address. THOMAS T. READ; Secretary.

Jan 3, 1914

Roger A. Markle was sworn in as director of the US Bureau of Mines on September 27, 1978, ending a 20-month period during which the Bureau was without a leader. Some Bureau observers wondered out loud if this delay was a signal that Interior was slowly pulling the rug out from under the agency. When Markle was finally tapped for the director's position-coal industry executive to lead an agency that had been stripped of its fossil fuel R&D functions as well as its safety and health enforcement role--the speculation was fast and furious: One camp had it that Markle was brought in to phase out the Bureau; others said that Markle's directive was to revitalize the organization by charting a new Bureau course. In March, with the proposed Department of Natural Resources making headlines, ME went to Washington to interview Markle about his first six months as director and the goals he has set for the Bureau's future.

Jan 4, 1979

The Victorian State Government recognises that the extensive brown coal deposits in Victoria are one of the State's key competitive strengths for economic development. The unique properties of the coal, together with the ease of open cut mining, make it suitable for a variety of new applications. Research and development activities are centred around applications which take advantage of the natural attributes and unique properties of the coal. The high reactivity and low ash content of the coal led to its selection for the Japanese brown coal liquefaction pilot plant currently operating in the Latrobe Valley, with support from the Victorian Government and the Coal Corporation of Victoria. Research and development of new brown coal based products together with many other areas of applied and fundamental research are being conducted in Victoria by Government research organisations, tertiary insti- tutions and private industry, with the objective of establishing new indus- trial developments based on Victoria's vast brown coal resource.

Jan 1, 1989

By Tomb. T. F., R. A. Haney

During the past several years, the Mine Safety and Health Administration (MSHA) has conducted studies in underground mining operations to obtain information on occupational exposures to diesel particulate (DP), mine environmental DP levels and on the effectiveness of methodologies used to control DP. The studies conducted were representative of four coal mines and 10 metal mines. The metal mines included two lead-zinc mines, one limestone mine, two potash mines, one zinc mine and four salt mines. Three of the four coal mines were using disposable diesel exhaust filters to remove particulate from the exhaust and one was using a reusable wire mesh filter. Results of these studies indicate that average DP levels in coal mines not using exhaust filters range from 0.9 to 2.1 mg/m3, The use of exhaust filtration devices reduced these levels by about 50% to 90%. Studies conducted in metal and nonmetal mines showed average DP levels ranging from 0.3 to 1.6 mg/m3.

Jan 1, 1996

By Calvin J. Konya

Backbreak behind the last row of boreholes can be a significant problem for blasting operations. Backbreak will interfere with the proper drilling and execution of the subsequent shot and can produce well defined boulders, which will not be broken by the subsequent shot. In order to determine the effect of timing on backbreak, a full scale blast with 6 1/2 inch boreholes was used to test the effects of timing. The test site was a quarry which had suffered from severe backbreak regardless of the blasting pattern or explosive used. One half of the production blast was loaded and initiated using the current technology at the quarry, the other half of the blast was deliberately timed in such a manner as to minimize backbreak. The timing was such to allow for ground movement in one row before the subsequent row fired. The test results proved that the amount of backbreak and flyrock could definitely be controlled with the selection of the proper borehole timing.

Jan 1, 1987

By Nancy S. Raymon

The Bureau of Mines investigated the effect of controlled additions of selected metal oxides, as well as the adjustment of the calcia-to-silica ratio on the high-temperature strength of refractory-grade periclase. Increases in the hot flexural strength of some periclase materials in the range of threefold to fourfold were obtained with additions of Zr02 and by adjustment of the CaO:Si02 ratio to the 2.5 to 3.0 level. Results show that for each periclase refractory raw material, there exists a combination of level of Zr02 addition and an adjustment to the CaO:Si02 ratio that optimizes the hot flexural strength of each of these materials. Data also indicate that the improved hot strengths can be attributed to the high-temperature secondary phases formed between the different levels of periclase impurities and the additives, resulting in improved intergranular high-temperature bond strength.

Jan 1, 1982

By Gordon T. Clark, Stephen H. Gleaton

This paper discusses the conceptual design of cut-and-cover tunnels currently being considered as one of the replacement options for the earthquake damaged, elevated double-deck highway and seawall built in downtown Seattle 50 years ago. The 4.8 km (3 mile) long, 6-lane improvement consists of 1.6 km (1 mile) of at-grade roadway with aerial interchanges, 1.6 km (1 mile) of large two-level cut-and-cover tunnels along the Elliott Bay waterfront, and retrofit of the 50-year old, 1.6 km (1 mile)long Battery Street tunnel and north transition to grade. Construction of deep cut-and-cover tunnels, in complex glacial geology overlain by hydraulically placed fill immediately adjacent the existing sea wall, will require extensive use of concrete diaphragm walls, ground improvement and dewatering. The potential liquefaction and lateral spreading of the fill materials in this active seismic region pose significant design challenges and risk.

Jan 1, 2003

By Marois R, Hauff P, Kowalyczk P, Lipton G, Bedell R, Neville R, Edmundo G, Ehling M, Kern R

The Canada Centre for Remote Sensing (CCRS) has developed an airborne sensor, the SWIR Full Spectrum Imager (SFSI) which detects in the Short Wave Infrared range of the solar spectrum from 1220 to 2420nm. In June of 1995, a demonstration flight was undertaken in the state of Nevada with the support of the companies listed above. The focus of the flight was to collect image data over well known mineral deposits with the objective of evaluating the applicability of this sensor to alteration mineral mapping. Some of the Nevada sites chosen include Cuprite and Goldfield, volcanic hosted acid sulfate systems; Yerington, a structurally complex porphyry copper deposit; and Virginia City, a Quartz- Sericite-Pyrite vein system with advanced argillic pods. Ground spectral data was collected with the PIMA-II spectrometer. Solar reflectance calibration was done by Desert Research Institute personnel at Virginia City and Cuprite. This paper will discuss the configuration of the sensor and present image and ground data for Goldfield and Virginia City.

Jan 1, 1995

By M. B. Thorpe

Land use and access to land are limiting factors in economic development in the Western region of Ghana. Mining uses land during operations and then rehabilitates the land as part of ongoing operations and closure. Golden Star Resources Limited (GSR) aims to contribute to the sustainability of the local economy during its operations and then post-closure. Following a series of alternative livelihood initiatives, GSR reviewed the success of these programs and decided to focus on an oil palm project that uses out-growers to reach the local economy. The project started using small holdings that were individually managed. However, the ongoing effects were limited. Following a review of the options, the Golden Star Oil Palm Project was started using land committed to the pro-gram by the Bogoso Mine. The initial program covered 275 ha with over 40,000 trees with 300 people involved in the development. The Traditional Authorities have committed additional lands to the project to a planned total area of 18,000 ha.

Jan 1, 2007

The Prince Lyell Mine has been the major production source at Mount Lyell since under-ground mining commenced in 1972.Three lifts of stopes have been mined to date, with the fourth, the 40 Series lift, to commence production this year. As the mine has progressed deeper, the ore haulage system has evolved to accommodate the mine's economic circumstances while maximizing efficiency.In the first, or 10 Series lift of stopes, ore was removed from drawpoints by L.H.D. units and tipped directly into rakes of 7 tonne rail cars. The original concept for deeper stoping lifts entailed L.H.D.'s tipping into long ore passes, rail haulage, underground crushing and hoisting to surface via the No. 1 Shaft. The suspension of the No. 1 Shaft project in 1976, due to economic difficulties, lead to the intro-duction of diesel truck haulage of ore, initially via the internal Prince Lyell Decline and now to surface via the Main Decline.

Jan 1, 1985

By Alan K. Burton

Having estimated fleet size and productivity, the next and final step in this analysis is to introduce cost. Total cost of the system is a combination of capital, operating, and any other external costs that may be incurred. The last item, external costs, can be particularly important when comparing one size or type of truck fleet with another. Once costs are calculated, it is possible to compare systems on a total cost, cost per hour, cost per ton, or any other basis that is required. Methods used vary from simple owning and operating costs to sophisticated discounted cash flow analyses involving optional fleet replacements over the project life.

Jan 1, 1976

A brief review of currently available "commercial" information on methods of treating ilmenite s to produce high titanium content "upgrades" is made. In this back- ground the CSIRO/Murphyores Process is described and its relationship to other methods Discussed.

Jan 1, 1972

By R Mancini

Explosive charge action on the medium is intrinsically dynamic (fast rising and fast vanishing). On the contrary, information available on rock strength is drawn from static behaviour, and it's commonly used to characterise the rock, even in blasting problems.

Jan 1, 1995