Search Documents

AustraliaÆs strong position as an aluminium producer and potential magnesium producer combined with rapid market growth in the automotive industry, proximity to Asia and other natural advantages points to considerable opportunity for downstream processing and manufacture with light metals in this country. Development of a vertically integrated light metals industry in Australia needs to be pursued with vigour, as does the continued development of global strategic alliances through the value adding chain.

Jan 1, 2000

By Thomas A. Morgan

The distribution of stress adjacent to each of 25 mine openings was determined by the borehole stress-relief method in the FMC Corp. Westvaco trona mine at Westvaco, Wyo. The purpose of the stress determinations was twofold: First, to study the effect on these distributions of various factors such as opening shape, stress level, and loading history; and second, to estimate the distribution of stresses adjacent to extensive high-extraction (85 to 100 percent) areas. Stress distributions in areas of low average stress correspond closely to the theoretical distributions based on elastic theory. However, in areas of high average stress, the stress distributions are of a type associated with plastic failure. The stresses adjacent to a mined-out area supported by remnant pillars were significantly higher than the stresses adjacent to another area in which the remnant pillars were removed.

Jan 1, 1965

By Syd S. Peng

Is the laboratory sized coal specimen much stronger than underground coal pillars? The answer to this question has a profound implication to many coal operators. It will decide how much of the coal reserve can be recovered. Or, in many cases, it will determine whether it can be mined economically. Recent trends in several eastern states to establish regulations regarding coal pillar design to prevent surface subsidence long after mining heighten the debates. And, in some cases, these trends highlight the existing practices that seriously question the conventional wisdom. Currently, nearly all researchers and practitioners agree that as the size of rock specimens increases, its strength decreases. This concept has been universally adopted as the basic principle for coal pillar design in the United States. Several formulas have been derived to account for this effect. The reduction factor for underground coal pillars ranges from one-half to one-sixth of the strength obtained in the laboratory, depending on the formula selected. Recent case studies indicate that the reduction factor is not justifiable, at east in some cases. The use of a reduction factor is based on the assumption hat smaller rock specimens as tested in he laboratory contain none or fewer fractures or planes of weakness than larger specimens or underground coal pillars. In other words, the larger the rock materials, the more fractures it contains and subsequently weaker in strength. Do all underground coal pillars have more fractures than laboratory sized coal specimens? Not necessarily. All coal contains cleats. Some are con¬spicuous but others are not. In terms of cleat density (number of cleats per unit area), there is no difference between an underground coal pillar and a laboratory sized specimen, provided the specimen size is larger than the cleat spacing, which is mostly 25 to 75 mm (1 to 3 in.).

Jan 1, 1993

By James B. Pfeiffer

TETRA Technologies, Inc., has applied its HDSIM metals precipitation system to treat a waste stream containing scrubber blowdown and process water from a smelter operation. The combined stream contained cadmium, lead, selenium, arsenic and zinc, plus some iron and copper. Treatment requirements included meeting stringent mass flow limitations for specific heavy metals. The HDS ? system can reduce the arsenic from 600 ppm to less than one ppm. The process generates a dense sludge that can be reprocessed in a smelter, eliminating the liability associated with landfilling. Flow diagrams and process details are discussed.

Jan 1, 1994

By Flavio Begazo, William A. Enrico

"Southern Peru Copper Corporation's Ilo Refinery, the largest in Peru, began operations in 1975 with a production capacity of 165,000 stpy. Southern Peru bought the Refinery from the state owned Minero Peru SA on June 1, 1994.The Refinery processes blister from Southern Peru's I/o Smelter. Blister copper is processed in an anode plant equipped with two 365 st tilting reverberatory furnaces, a 26 mold casting wheel and an anode press machine. Copper is electrorefined in a tank house equipped with 768 commercial cells, 44 stripper cells, and 40 liberator cells, utilizing two electrolyte circuits and a 21,000 Ampere rectifier.During 1989 through 1994 a program for improving productivity was carried out by increasing the number of cells and increasing current density to the total rectifier capacity. As a result, a capacity 215,000 stpy of refined copper, 2 million tr. oz silver and 6,000 tr. oz gold per year was achieved. In 1994 Southern Peru announced plans to increase capacity to 250,000 stpy of cathode with a US$ 18 million investment and a US$ 2 million investment in environmental improvement projects, as part of the purchase agreement with the Peruvian government.This paper outlines the scope of the SPCC lio Refinery modernization and environmental program. It describes the implementation of the Electrolytic Plant expansion based on instaliation of polymer concrete cells, a new rectifier, a new selenium roaster and a Precious Metal Plant upgrades."

Jan 1, 1997

By L. Cheng

This report describes a laboratory investigation of the effectiveness of low-pressure steam and a steam-water spray sequence for the collection of airborne respirable (<10 µm) coal dust. Comparison of present results to previous results obtained with water spray alone indicates that the use of steam in a steam-spray sequence increases the collection efficiency by about 14 percent over that obtained by water spray alone. However, the use of steam to collect airborne dust requires cooling the steam-dust mixture in order to achieve condensation of the steam, and steam does not appear to be an attractive approach for collecting airborne dust in underground coal mining operations.

Jan 1, 1974

By D H. Lee, J F, J H. Rubinstein

This paper examines the problem of optimising the life-of-mine costs of an underground mine, focussing particularly on the costs associated with the underground development needed to provide access to and haulage from the ore zones. This mine optimisation problem is modelled as a network and a solution technique is outlined. The effectiveness of this solution technique is then demonstrated by applying it to a prototype test example and some actual case studies. Finally, extensions of this technique to other underground mining problems are discussed.

Jan 1, 2000

By W. W. Adams

This bulletin covers all mines in the United States that were operated in 1936 to produce metallic ores and all mines that were operated to produce nonmetallic minerals other than coal, stone, sand, gravel, or their products. Reports from mine operators revealed a better safety record for fatal accidents in 1936 than in any other year except 1934 during the 26 years for which annual surveys of accidents in the mineral industries of the United States have been conducted by the Bureau of Mines. On the other hand, the record for nonfatal injuries, although better in 1936 than in any year prior to 1930, was not as good as it was from 1930 to 1935, inclusive.

Jan 1, 1939

By Lloyd A. Morley

The performance of electrical grounding systems in open-pit metal mines is evaluated, using techniques which are described thoroughly. The normal electrical distribution and grounding practices used in metallic open-pit mines are reviewed and compared with coal mine usage. The results are used to generate the included recommendations for Federal Regulations concerning open-pit metal mine grounding systems.

Jan 1, 1976

By E. V. Konoplev

Russia is one of the largest manufacturers of potash fertilizers in the world. Processing of potash ores basically is carried out by a flotation way. Potash ores of the Verhnekamsky potash deposit contain sylvite (KCl), halite (NaCl) and water insoluble impurity (up to 8 %), presented silicate- carbonate minerals, easily slimed by ore crushing in rod mills. Ore of some deposit sites, developed by ?Uralkali? Co, contains a significant amount of a carnal-lite (KCl.MgCl2.6H2O). Work practice of flotation potash plants has shown, that increase of car-nallite content in ore leads to increase magnesium ion content in a circulated plant brine (saturated salt solution of potassium and sodium chlorides-sylvite brine) and to deterioration of indicators of ore processing. In the Paper we present results of researches of floatability of various size sylvite and influences silicate-carbonate slimes on sylvite flotation in brines with the various magnesium chloride content. It is established, that with increase magnesium chloride content in the brine mainly decreases the flotation of coarse sylvite and amplifies adverse effect of silicate-carbonate slimes on sylvite flotation. In this connection deterioration of potash ore flotation is caused not only decrease sylvite floatability but also strengthening adverse action of water insoluble impurity on potash flotation. It is shown that the application of frothing agents, which render the stronger dispersive action on the colloidal-micellar structures of amine in the salt solution increases the absorption of collector on the sylvite and improves the flotation of sylvite into magnesium the containing salt solutions. The application of an organic depressor to the greatest degree of decreasing the absorption amine on the slimes and to the smallest degree possessing anionic properties proves to be most effective with the flotation carnallite of the containing potassium ores. It is offered the application the frother on a basis of glycol ethers and organic depressor on a basis of urea-formaldehyde resin. Results of industrial tests developed reagent modes for flotation treatment of ores with the raised carnallite content (to 6 %) on ?Uralkali? Co plant have shown that their application has allowed to receive equivalent indicators potash flotations at change of magnesium chloride content in the brine from 0.7 % up to 2.4 % .

Jan 1, 2014

By L. Lariviere, M. Grenier, R. Khalili, D. Shook

A mineral processing facility near Montreal, CEZinc, Noranda Inc., has recently implemented a leading-edge intranet solution for monitoring the performance of plant operations, and providing condition-based maintenance. This innovative multi-faceted software implementation incorporates: web-delivered plant information systems; area-wide control loop performance assessment (using sophisticated algorithms to evaluate poorly performing controllers); and integrated alarm management functions.The system has enabled a project to improve plant operations through better process control. Maintenance technicians, engineers, supervisors and managers all can see the performance of the controllers, and the performance of the plant itself, through webdelivered graphics and reports. Information is combined from many sources, real-time, historical, relational and analytical, to provide a complete picture of plant operation.The web-based solution centralizes the administration of user access, and simplifies the deployment of several different kinds of information to many desktops. It is an extensible system that allows users to create and share their own web pages and data views.The paper will discuss the solution architecture and the improvements the IT, operations, maintenance, and engineering groups have experienced, and overall benefits to the facility.

Jan 1, 2003

By Kenneth A. Pidgeon

This paper presents a case history on mitigating vibration problems associated with the installation of steel sheetpiles. The project in-cludes installation of steel sheetpiles for a utility trench within 40 feet (12.2 meters) of a very sensitive manufacturing facility. Numerous production line quality control instruments and manufacturing processes within the manufacturing facility are extremely sensitive to vibrations. To minimize the impact to the owner, we specified that the contractor perform a vibration study using different types of pile hammers. The results and conclusions of the vibration study are presented in this paper.

Jan 1, 1995

By R. S. Dewey

The purpose of this study was to assess the various aspects of public safety related to the thousands of abandoned or inactive underground mines found throughout Western Colorado. Review of available published mine inventories yielded data on over 8,000 abandoned underground mines. A random sample of 200 mines was then selected for field visits representative of mining activity in Colorado. Inspections of the openings at two hundred abandoned underground mines were performed recording descriptive information regarding the opening, the mine site, the surrounding area, the primary opening hazard, secondary hazards related to structures or dumps, other openings to the same mi ne, available construction materials, possible safeguard methods, and any special observations such as apparent activity, previous closure attempts, environmental constraints on construction, and access problems. Of the 200 mines visited, twenty mine openings representative of varying geologic, environ-mental, access, and mining conditions were selected for detailed low-cost safeguard application. Description of these safeguards is presented in narrative, itemized labor-materials equipment tabulations, and illustrations. Research into the regulations of mine closure and safeguards was also undertaken to determine jurisdiction of public lands. Recommendations were suggested to improve the awareness and ability to continue this program into an implementation stage.

Jan 1, 1980

By H. F. Seifert

THE classification and preparation of non-ferrous scrap metals is a subject of interest to every individual and corporation that employs in its processes of manufacture non-ferrous metals and alloys and accumulates in such manufacture scrap from these materials for disposition in the form .of turnings, borings, short ends, punchings, clippings, grindings, washings, etc. All too frequently the disposition-of such scrap is left to individuals who have no knowledge of the subject either from a metallurgical or a commercial standpoint, or both. Much money is thus lost which with a little more intelligent effort might be saved, and in this day of fierce competition and small profits such an opportunity cannot be ignored. The Mineral Resources of the United States for the year 1925, the latest issue available (Part 1, page 221), gives the secondary non-ferrous TABLE 1.-Some. Secondary Non-ferrous Metals Recovered in the United States for the -Year 1924-25 Material Short Tons Value Copper, including that in alloys other than brass.... 250,600 8 71,170,400 Brass, scrap remelted : 242,300 56,270,800 Lead as metal : 112,420 39,477,100 Lead as alloys 112,460 Zinc as metal 61,430 11,359,000 Zinc in alloys other than brass 13,300 Tin as metal 7,950 Tin in alloys 23,000, 35,165,400 Antimony as metal 1 3,794,000 Antimony in alloys : 10,839 Aluminum as metal 17,700 24,816,000 Aluminum in alloys 26,300 Nickel as metal 191 1,518,000 Nickel in non-ferrous alloys 2,109 Total l 882,600 $243,570,700

Jan 1, 1928

By Amr Sallam, Ahmad Mohamed, Mohamed Alrowaimi

Renewable energy, in the form of wind and solar, has emerged as main source of energy in the modern society. The wind industry has substantially grown over the last two decades to become a key player in providing energy to public. Wind turbines are getting larger, taller, and more efficient every year. The foundation is a major component of the wind turbine system. The wind turbine foundation must provide short and long-term stability for the overall turbine to allow continuous and safe turbine operation for energy production. The turbine serviceability and stability requirements must be geotechnically and structurally satisfied. In North America, major foundation types currently utilized in the wind industry include gravity spread foundation, mono pier foundation, and pile foundation. In this case study, a Post Tensioned Pile Cap (PTPC) foundation was used to support a 3.15-3.4 Megawatt turbine with 125M Rotor supported on 87.5M-hub-height tower. Soil anchors in the form of Auger-Pressure-Grouted-Displacement (APGD) piles and Continuous Flight Auger (CFA) piles were utilized. Four distinct subsoil conditions were identified, and for which four pile designs were adapted. Due to the occasional encounter of stronger soils at 50 to 55 feet (15.2 to 16.7 m), shorter pile design was preferred. To satisfy the design uplift load, pile post grouting were utilized to increase the shaft capacity of the piles. In this paper, the pre-production pile load test program will be described. The pile load test procedure, analysis, and results will be presented. A discussion will be provided, which led to the selection of the optimum pile design to support the high tension loads taking into consideration pile length limitations.

By D. W. Frommer, M. M. Fine

Laboratory investigations have produced flotation concentrates contain- ing 91 to more than 92 percent titania, with fair recoveries, from the Christy property, Hot Spring County, Ark. The titanium-bearing ore on the Christy property occurs in a quartz-clay- iron oxide mineralization, which contains, on the average, about 6.0 percent TiO2, chiefly as the mineral brockite; brookite and rutile are different crys- talline forms of titanium dioxide. Recent work by the Bureau of Mines has shown that titanium chloride can be produced readily from the rutile-type mineral by reduction with coke fol- lowed by low-temperature chlorination. Metallic titanium is in turn derived etallic from the chloride by the Kroll process .

Mar 1, 1952

By T. G. Joseph, G. W. Hansen

"This paper considers the duty cycle of an electric cable shovel and correlations with measured passive seismic responses of the underfoot oil sands material in-pit. It has been observed that the cyclic activity during operation of any shovel in the oil sands environment causes the material to deteriorate and provide a less than ideal footing for this large item of equipment, whose dead weight approaches 1500 tons with a footprint of merely 75 sq. yd. Consequences are manifested in the form of carbody and side frame cracks, and associated downtime, maintenance activity, cost, and subsequent loss of availability.The objective of these considerations, as part of the Oil sands-Equipment Interaction Program (OsEIP), currently a joint venture between Syncrude Canada Ltd., James Progithin International (JPi) Ltd., Caterpillar Inc., P&H MinePro and the University of Alberta, is to identify and provide feedback to the manufacturer and end user of adverse shovel-ground conditions. This would enable the manufacturer to incorporate greater knowledge into the design process and the end user to direct operations in an enhanced proactive maintenance stance."

Jan 1, 2002

Lime and cement manufacturing has a proud history in Otago, with the earliest lime kilns appearing around 1849 at Caversham and Kaikorai in Dunedin . At Dunback or Makareao (to be precise) three well-type kilns were built by the government in 1899. In 1909 these kilns were leased to the then Milburn Lime and Cement Company. They erected a large brick Schmatolla kiln in 1909, elliptical in plan and fired by coal gas. The kiln operated up until 1944 before being left derelict. The quarry which supplied the kiln also supplied the Burnside Cement works from 1929 up until its closure in 1988. The quarry was shifted to the top of the hill in the 1950s.

Jan 1, 1992

DML Resources Limited - Mining Division produced over 50 000 oz of alluvial gold in the 1995 - 1996 year from five operations located in the West Coast and Otago Regions on the South Island of New Zealand. DML Resources Limited - Mining Division have a twenty year history of alluvial gold mining development in New Zealand. Recent expansions have seen the establishment of two operations in Chile whilst exploration continues in Bolivia, Peru and Argentina. The overseas growth is based on a stable production base in New Zealand focussed on the West Coast and Southland/Otago present and future operations. DML Resources consider that the mining potential in the Arahura Valley on the West coast will be fundamental to their New Zealand operations for some time. Collectively the plants operating in this catchment are referred to as the Poutini Project. Recent and late Pleistocene gravels derived from the erosion of the Alpine Schists running parallel to the Alpine Fault located on the Pacific/Australian Plant boundary are thought to be the sources of the alluvial gold in the Arahura and adjacent catchments. These gravels have been extensively mined for the past 130 years yielding some six million ounces over this period. Production from the Poutini Project started in 1989 and stood at approximately 35 000 oz for the 1995 - 1996 year. This production was split among three plants each working different areas of the deposit. Recovery techniques from each of the plants are fundamentally the same. Gravels are fed to a floating treatment plant where, following screening, the gold is recovered using jig plants and knudsen bowls. Overburden to wash stripping ratios vary between zero and seven to one with plants treating between 80 and 250 cubic metres per hour. Restoration of the land following mining is undertaken progressively. All land in the Poutini Project area mined to date has been restored to a standard suitable for dairy farming purposes. The Poutini Project is a cooperative venture between the Maori landowners and DML Resources Ltd. The Arahura River has particular cultural significance to the Maori as it is the source of the much valued greenstone or pounamu a type of jade valued for jewellery and tools. The Poutini Agreement was signed in 1989 setting out the role of each party in the mining of the Arahura and adjacent lands. Current exploration and development should extend the resource to allow mining to continue on the Poutini project for an additional three to five years at current gold prices. Production within new Zealand beyond this point may be compromised by increasing difficulty in gaining access to prospective areas within New Zealand, lowered margins due to high New Zealand dollar exchange rates and the overall lowering of alluvial headgrades throughout the West Coast and Otago/Southland regions. To counter these effects DML has continued to improve on operational efficiency and performance monitoring to optimise the mining practices used. This paper detains the background to the Poutini Project, the geology, plant and equipment used together with descriptions of the current mining methods employed.

Jan 1, 1996

By Oliver Bowles

Since 1922 when the Bureau of Mines issued a report2 covering the slate industry in detail, changes in technology have taken place which have an important bearing on the industry. The present paper comprises a record of these changes. Though the value of slate, for roofing, structural, blackboard, sanitary, and electrical uses is generally recognized, it has many competitors. To meet this constantly increasing competition producers are promoting economies in manufacture, and improving processes, thereby lessening costs of production, and are placing on the market products of the highest possible quality, thus creating satisfaction and confidence on the part of the user. This endeavor to place the industry on a better basis, both as regards processes and products, is shown in the recent developments in technology which are presented herein. Valuable assistance in obtaining data for this paper was given by W. S. Hays, secretary of the National Slate Association, N. M. Male, president of the National Slate Association, and Robert Notvest, consulting engineer, Cleveland, O.

Jan 1, 1926