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By Charles Wraith

THE property of the Roan Antelope Copper Mines, Ltd., is situated at Luanshya, north-central part of Northern Rhodesia, and is connected with the main line of the Rhodesia Railways, Ltd., by a 24-mile branch line from N'dola. Most of the material and supplies that are not available in Africa are shipped into the country via Beira, on the East Coast of Africa, a distance of 1473 miles from Luanshya and the nearest ocean port. The output of copper is shipped by rail to Beira and thence by boat to the market. Passenger travel is mostly via Cape Town, a distance of 2162 miles from Luanshya. Excellent passenger trains operate on regular schedules between Cape Town and Northern Rhodesia. Luanshya is 13° south of the equator at an elevation of 4000 ft. above sea level, and has a mild healthful climate. During the rainy season, from October to March, the rainfall averages 53 in. The area is pro-fusely covered with vegetation. An ample supply of water for industrial and domestic purposes is available throughout the year. The more important supplies for smelting purposes, such as wood, coal, limestone, silica, quartzite, and clay for "dolly" mud, are con-veniently available. Excellent grades of coal, coke and firebrick are obtained from the Wankie Colliery Co., Ltd., Southern Rhodesia. The Wankie colliery has just completed the erection of equipment for the manufacture of silica brick. An ample supply of quartzite of good grade is available for this purpose. Silica brick is also obtained from the Belgian Congo and from India. Limestone is quarried from a large deposit a few miles from Bwana Mkubwa, which is 30 miles by rail from the smelter. An abundant supply of clay for "dolly" mud and for lining launders is available within a short distance of the smelter.

Jan 1, 1933

By Hennessy F. L

IntroductionEvolution of the Present SmelterRoastingFiringHearth SlopeDust HandlingFurnace DetailsSmeltingFurnaceFeed DeliveryPulverised Coal FiringWaste Heat BoilersDust HandlingAir PreheaterReverberatory Slag DisposalConvertingVesselsAir SupplyMatte TappingConverter Slag HandlingPurchased Ore PlantINTRODUCTIONSmelting in blast furnaces commenced at Mount Morgan in 1906, when copper, which interfered with gold recovery by chlorination, became an asset. After various changes in blast furnace practice, reverberatory smelting com...

Jan 1, 1952

The Olympic Dam smelter utilises Outokumpu Oy, flash smelting technology to produce blister copper direct from high grade copper concentrate.This paper describes the unit processes involved, including filtering/drying, materials handling, smelting, gas/dust handling, waste heat recovery, sulphur fixing, anode refining and casting.

Jan 1, 1993

By C. Damiani

The Chuquicamata smelter, operating since 1952, has gone through several developing stages which have been characterized by the addition of peak technology for copper concentrate smelting (Teniente converter and Outokumpu flash furnace) with an intensive use of technical oxygen, which has permit-ted to partially discontinue the reverberatory furnace utilization. This paper shows the main indicators and operational practices at present, as well as those concerning maintenance aspects. Finally, the most relevant topics related to the future development of the smelter are mentioned with special remarks on the Decontamination Plan, which allows US to keep the high level of production, reducing the emission of contaminants according to the legal requirements in force.

Jan 1, 1993

By Bohrn W, Milionis K, Tessmer G, Reidetschlager J

The share of electric arc furnace based steel production is increasing - New technologies for the production of virgin raw materials for EAF production are under development and on the market - VAI has a strong position in the field of scrap substitution technologies with their COREX«-, COREX«-DR and FINMET«-technology. In late-1998 the steel plant SALDANHA was started up successfully. This integrated compact mill is using the COREX«-technology as hot metal and a combined DR-plant as DRI production unit. Also in 1999 the BHB FINMET« plant Port Headland went on Stream.

Jan 1, 1999

By Y. L. Ding, N. A. Warner

Cylindrical pellets made from graphite and chromite mixtures were reduced in high-carbon ferrochromium melts at 1 600-1 695 degrees C, under an atmosphere of almost pure CO. The reduction rate, as measured by gas evolution, increased with increasing melt temperature and graphite addition and with decreasing pellet diameter or height, although reductant particle size had a very limited effect on kinetics. At a pellet size, heat and mass transfer were significant in controlling the early stages of reduction of large pellets while at chromite grain size, gas diffusion was probably a rate-controlling step. The time required for dissolution of unfluxed pellets into the melts was significantly longer than that for reduction. This indicates that pellet dissolution may be the limiting factor in determining the operating parameters for a proposed new process to produce high-carbon ferrochromium using melt circulation

Jun 19, 1905

By Ray H. S, Galgali R. K

It is well accepted that the blast furnace will continue as the main route for iron-making for many more years. However, its limitations have motivated researchers to look for alternative routes, particularly, those where non-coking coal is used for liquid iron production. Smelting reduction (SR), where coal and oxygen are used to produce liquid iron and power is now receiving serious attention. Several smelting reduction reactors are now operating in pilot plant scale and one or two have reached commercial status.

Jan 1, 1999

By T. J. A. Smith

This paper provides an overview of some of the key issues in design of smelter gas handling systems, with particular reference to sulphide smelting plants. In both primary smelting and converting. gas handling and treatment systems often represent the major capital cost component. There is also ample evidence that poor system design can be a major cause of smelter down time, lost production and unforeseen high maintenance costs. The paper discusses these issues and offers guidance for improved design.

Jan 1, 1992

For some years MINING ENGINEERING has published abstracts of the articles appearing in each issue and also of the Transactions papers published in the Quarterly. Beginning this month, a list of key words is being given with each abstract as an aid to indexing the articles for ease in retrieving them when they are needed. The value of a home or office system of indexing and retrieving technical articles is hard to over-estimate. How often is it that a technical problem comes up and someone says: "Oh yes, I've read something about that." Many hours can be expended tracing down that nebulous source. A modest indexing and retrieval system will save those tedious hours, and the person who is able to produce technical documents when they are needed will achieve an enviable status for being on the ball.

Jan 1, 1964

By T. J. White

A synthetic Mineral Immobilization Technology (SMITE) has been developed for stabilizing municipal and hazardous waste incinerator ash. Tailored additives are introduced to the ash in a' first stage that pre-stabilizes all the toxic metal components in non-volatile forms. and in a second pyrometallurgical stage, these are converted to insoluble mineral analogues. It has been found that a combination of apatitie. spinal, anhydrite and monazite can immobilize all the ash components at high waste loading and high density. Typically the stabilized products contain in excess of 50 wt% ash and have densities of 2.5- 3.0 g.cc-1. Toxicity Characteristic Leach Procedure (TCLP) testing has demonstrated that the products well satisfy regulatory requirements. The cost of production and disposal of SMITE waste forms in 2-5 less expensive than. convential methods of solidification/stabilization. This paper will describe the principles of SMITE design for ash stabilization, outline the fabrication procedure, and present comprehensive microstructural and chemical data to validate waste form performance.

Jan 1, 1996

The Janet Annenberg Hooker Hall of Geology, Gems and Minerals, located in the National Museum of Natural History, Smithsonian Institution, in Washington DC, opened in September, nine years after initial fundraising efforts were begun. The 1,858-m2 (20,000-sq ft), $16-million hall was mostly funded by private groups and individuals, including $1.7 million from 43 National Mining Associa¬tion (NMA) member companies. Companies that contributed more than $100,000 included Cyprus Amax, Phelps Dodge, Asarco, Homestake Mining, BHP, Caterpillar, Cleveland Cliffs, Exxon Coal and Minerals, Freeport-McMoRan, Newmont Mining and Peabody Holdings. The mining industry's contributions funded a walk-through Mine Gallery. It. features diora¬mas of four mines, as well as numerous specimens associated with the mines. The Mine Gal¬lery demonstrates to the public the importance of mining. The hall was named in honor of Hooker. She contributed $5 million in cash plus the Hooker Yellow Starburst Diamonds to the project. The hall is touted by the Smithsonian as the "most comprehensive earth science complex of its kind." It consists of seven galleries, each devoted to different aspects of gems, minerals and rocks. In addition to the Mine Gal¬lery, the hall contains a collection of gemstones and jewelry pieces, an extensive collection of minerals, a gallery devoted to plate tectonics and a gallery devoted to the moon, meteorites and the solar system. The new hall is a complete makeover of the old and outdated Geology Hall. It was built in the 1960s and finally closed to the public in 1995.

Jan 1, 1997

By William G. Christy

EFFORTS at smoke abatement date back to the year 1273 in England when a law was passed prohibiting the use of "sea cole." The law was not enforced, so King Edward I, 33 years later, appointed a commission "to enquire of all such who burnt sea cole in the city or parts adjoining, and to punish them for first offense with great fines and ransomes, and for the second offense to demolish their furnaces." Many other commissions have since been named to investigate the smoke problem in England, but it still persists in many British cities. In the United States the movement to abate the smoke nuisance started in certain Middle Western cities, and has made considerable progress. Until recently, the coal-producing industry co-operated little in smoke¬abatement programs, taking the attitude that smoke elimination is the dealer's or user's responsibility; and the dealers, in turn placed the responsibility entirely on the user.

Jan 1, 1942

This chapter focuses on smoke as it relates to escape from underground mine fires. Among the topics discussed are the measurement of visibility in smoke; smoke-related hazards such as the production of CO, hydrochloric acid (HCI), or other byproducts of combustion; and miners' personal experiences while escaping through smoke. Smoke Measurement and Visibility In general, smoke consists of hundreds of thousands of very small particles. These particles have some "size," usually expressed in terms of their diameters, and they have some concentrations, usually expressed either in the number of these particles per unit volume or the total mass of the particles per unit volume. Humans cannot see individual smoke particles because they are too small. Similarly, "umber concentrations" and "mass concentrations" of smoke particles do not have much meaning to people unless they are trained technically. Still, individuals know that they can see smoke, independent of all the technical jargon used to describe it. Also, they know that when the smoke level gets too high, it is no longer visible. In fact, nothing is visible because the smoke absorbs all of the light in its surroundings. The eye is only sensitive to light in the wavelength region from about 400 nm to about 700 nm. The maximum sensitivity of the human eye is to light that has a wavelength of about 555 nm. It is important to know how the eye responds to light because if its response is known, it is possible to use a light detector that has almost the same response as the eye. Such a detector can then be used to quantify the visible characteristics of smoke because it responds in the same manner as the human eye. Smoke is visible because it either scatters or attenuates (diminishes) light. In some instances, smoke is visible because the smoke particles reflect light which is then detected by the eye. The eye actually "sees" an intensity of light that has been reflected from a cloud of smoke particles. Imagine shining a flashlight into a cloud of smoke. Someone off to the side can actually "see" the beam of light as it traverses the smoke cloud. This is called scattering. Smoke is also visible be¬cause it attenuates light. Imagine having someone shine a flashlight into your eyes. As smoke begins to build up along the beam of the flashlight, the light begins to dim. The smoke is visible because it is now reducing the intensity of light that falls upon the eye. As the smoke level increases, it is said to obscure our visibility. When the beam is no longer visible, the smoke obscuration is said to be 100%. In other words, none of the light energy from the flashlight makes its way through the cloud of smoke. Another way of saying that the obscuration is 100% is to say that the transmission of light through the cloud is zero.

Jan 1, 2000

By R Lau

In recently completed road tunnel projects in Queensland, such as the Airport Link and the Clem7 tunnels, there is a smoke duct running along the roof of the carriageways to extract smoke in case of fire. In New South Wales, no road tunnels have a smoke duct. In the Melbourne City Link tunnels, there is a small smoke duct running along the roof. All of the tunnels are safe as claimed by the designers and authorities. However, there is significant cost associated with providing a full size smoke duct compared with no smoke duct. This paper is going to present a comparison of the road tunnel safety with a smoke duct and those without one from a risk perspective. It further discusses the cost-effectiveness of such provisions and whether similar levels of safety could be achieved without a smoke duct.CITATION:Lau, R, 2014. Smoke duct or no smoke duct for road tunnels, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 83–86 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By A. E. Ketler

Optical smoke monitoring fills an important gap in ventilation and fire safety: namely monitoring of smoky, low temperature fires where little CO and heat are generated. Smoke monitoring also avoids the nuisance alarms due to diesel exhaust, battery chargers, blasting and welding. The smoke optical density (OD) fire alarm standard specified by MSHA presents an opportunity for improved safety. Experience of actual mine usage of the SmokeBoss*100 is reviewed, with particular regard to effectivity, maintenance and cost.

Jan 1, 1995

By R. A. Franks, G. F. Friel, J. C. Edwards, L. Yuan

The reversal of smoke products-of-combustion (POC) from a mine fire was determined in a mine section with the airway connectivity of an electrical Wheatstone bridge. Four diesel-fuel fire experiments with fire heat-release rates between 504 and 771 kW were conducted in the Safety Research Coal Mine (SRCM) located at the National Institute for Occupational Safety and Health’s (NIOSH) Pittsburgh Research Laboratory (PRL). Smoke reversal propagated upwind from the fire with significant leakage into the upwind diagonal airway and without causing a complete reversal of airflow in the diagonal airway. A control measure consisting of a brattice suspended half entry height from the entry roof was determined to abate the smoke rollback. Computational fluid dynamics (CFD) analysis of the smoke movement agreed with the measurements.

By E. Lentilucci, A. Dey, X. Liu, A. Datta, S. Ghosh

The segmentation of quarry blast smoke plumes is a crucial research area that has the potential to enhance safety, environmental monitoring, object detection, and regulatory compliance in the mining industry. Smoke plume segmentation can be used to identify the spatial extent and temporal evolution of smoke plumes generated by the blast. This information can be used to improve the understanding of blast dynamics and optimize blast designs. Furthermore, smoke plume segmentation can assist in identifying potential environmental and health hazards associated with the release of smoke and dust particles into the atmosphere during quarry blasts. However, many current smoke plume segmentation algorithms are designed for segmentation of smoke plumes from fires and are not suitable for segmentation of plumes from quarry blasts. The proposed method in this paper leverages the video frame captured before the blast as a stationary background image, which helps to reduce other confuser objects present in the image along with a selfadaptive clustering method. The color channels of the image are utilized based on the different contrast properties of the smoke, with a self-adaptive gradient compensation applied for edge detection of the smoke plume. This approach offers a novel and effective way to segment smoke in quarry blast analysis, with potential applications in the calculation of noxious gas volume and concentration within the plume. Compared to other algorithms, our method improves accuracy, decreases the false alarm rates, and reduces the overall miss rate. Overall, this paper contributes to the research on smoke plume image segmentation, particularly for quarry blast smoke plumes, which possess unique characteristics that require specialized algorithms for accurate segmentation.

Jan 1, 2024

By John W. Goth

This article, though not common feature material, should be of reader interest. Goth made this presentation as the keynote address at the 19th Annual Intermountain Minerals Conference in Vail, CO, in August. Introduction Working backward, what is an LDC? LDC stands for Less Developed Country. LDCs play a dynamic role in world supply and demand of basic materials. They occupy an equally important position in international marketing and finance. I will explain later some of my concerns with LDCs. First, I want to address an issue I think is of equal or even greater concern. Mining and High Technology Unfortunately, many people believe that America must make a decision now between being a smokestack-based economy or a high-technology-based economy. Some would have you believe that smokestack America is dead. Our only option is to turn to high technology, in a manner similar to countries such as Japan. Presumably, when we talk about high-technology industries we envision organizations that came into being within the last decade or so and incorporate microelectronics, biotechnology, and interconnected computers. The entire workforce is clad in lab coats and there are few employees in proportion to the work performed. High-technology industry is not labor-intensive work thanks to the efficient robots used. On the opposite side are smoke-stack industries, that we presume include the older, basic industries such as mining, agriculture, iron and steel manufacturing, ship-building, auto manufacturing, and nearly all forms of construction. These industries are judged to be labor intensive, requiring unsophisticated and untrained employees who succeed by the sweat of their brows rather than by advanced degrees in mathematics and physics. If these are indeed the presumptions about high technology versus smokestack industries, then I submit that those presumptions are a disaster. They are wrong and far from the truth. Smokestack industries, such as mining and the others mentioned, are indeed much older than some of the recently founded high-tech industries. But this does not mean that those smokestack industries are low-technology industries. On the contrary, American agricul¬ture is a very high-technology industry whose crop yields are the envy of the entire world. Mining uses virtually all of the advances available through modern technology. Far too many opinion leaders still envision mining as Humphrey Bogart and John Huston in the movie Treasure of the Sierra Madre. Yet there are many who hold the opinion that our basic industries are dead and that this country's future depends on specialized high-technology industries and services. That is tantamount to announcing we will continue to build space shuttle vehicles, but we no longer need launching pads and landing fields. The point is, we should not be wasting our time talking about "new" industries and "old" industries. We should devote our time and effort to industries that are effective and efficient in meeting our needs, in contrast to industries that are not effective and efficient in meeting our needs. Less Developed Countries That leads me to some of the problems I perceive with policies regarding the previously mentioned LDCs - Less Developed Countries. Far too many people do not realize that many of the smokestack industries being lauded in Less Developed Countries are being operated at a loss and to the detriment of worldwide industry. And the losses incurred

Jan 12, 1983

Smoky Valley Mining Company, Round Mountain, Nevada, was the pioneer operation designed for large scale heap leaching of crushed gold ores. It is located in the Big Smoky Valley which stretches 160 km (100 miles) through central Nevada west of the Toiyabe Mountain Range. Gold was first-discovered at Round Mountain, 88 km (55 miles) north of Tonopah, in 1905; and mining in the area included placer operations, which ran from 1946 to about 1960. Smoky Valley Mining Company is a partnership of Felmont Oil Co., Case-Pomeroy & Co., and Copper Range Co., with the latter being wholly owned by Louisiana Land and Exploration Co. In 1969, an option on the Round Mountain property was acquired by Copper Range, and during 1974 a decision was reached to proceed with mine development and plant construction. Ore reserves were reported at 10,537,000 mt (1 1,617,000 st) of 2.09 g per mt (0. 061 oz per ton) gold using a cut- off grade of 0.69 g (0.02 oz). Silver content was approximately 2.4 g per mt (0.07 oz per ton) and the waste to ore ratio was about 1: 1. By the end of 1976 heap leaching was in operation. The ore is a rhyolite tuff, sometimes described as a gold porphyry with highly abrasive qualities but which does not break down into slimes upon contact .with cyanide solutions. Gold is unevenly distributed through the ore but as a whole it is in a very finely divided state. Climatic conditions are extreme in central Nevada. Summers are hot and dry while winters are windy and cold with subfreezing temperatures. Elevation of the property is about 1,920 m (6,300 ft). Precipitation averages 203 mm (8 in.) per year. Until February of 1980, leaching was continued until the temperature reached minus 2ºC (28º F), and about 10 months leaching was the average. Water for the operation is drawn from the Toiyabe Mountains through a 13. 7 km (8. 5 mile) pipeline, originally installed in 1915, or from wells in the valley bottom. The plant requires make-up water at the rate of about 1,500 liters per min (400 gpm). On a schedule of three shifts, seven days per week, the daily output at Round Mountain amounts ,to 12, 700 mt (14, 000 st) consisting of 6,350 mt (7,000 st) each of ore and waste. Ore is hauled with a fleet of 45 mt (50 st) trucks and dumped into the 1,0.70 by 1,650 mm (42 by 65 in. ) gyratory primary crusher located near the pit. The primary

Jan 1, 1981

By Lye GN

Rock mechanics investigations have shown that some major slopes in the Panguna pit would be stable at angles in excess of 500 providing near-surface instability could be controlled. Excavation of final batters at angles between 55¦ and 60¦ is now being carried out using D10 dozers with berms at 45 to 60 m centres. A trial slope with berms at 90 m centres is planned. Shotcreting of weak zones combined with crest reinforcement, with rock anchors and dowels, is used to provide protection against erosion and toppling of the crests. Overall slopes excavated in this way are of the order of 10¦ steeper than slopes obtained by blast and shovel excavation.

Jan 1, 1986