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By D Blair, L Fergusson, G Barros

"The purpose of this paper is to present the findings of a waste rock remediation program conducted at a gold mine in New South Wales (NSW) over a six-year period. The treatment of waste rock dumps included the longitudinal results of one-off applications using: ViroMine Technology, including the application of a chemical reagent called Terra B, which is a benign, clay-like substance derived from processed bauxite and other sources lime and biosolids (added for nutrient value) clay capping and topsoil compared treatment outcomes from these three approaches to a control.Parameters measured in the program included leachate pH, total actual acidity (TAA) and chromium reducible sulfur (CRS), Al, Cd, Cu, Fe, Mn, Ni, Pb, Zn, and tree height and vegetative cover density with data collected at regular intervals over a six-year monitoring period. Findings over the life of the study indicated, for example, that leachate pH in the control area was 4.5 in year 1 falling to 4.0 by year 6; pH in the lime and capping treated waste rock was initially raised to about 5.5 after treatment but fell to 5.0 within 24 months and remained a low 4.7 by year 6; pH in the Terra B waste rock was 6.8 in year 1 immediately after treatment, and actually increased to 7.3 by year 6 with no further treatment. This finding is of relevance because it effectively profiles the acidity curves of waste rock control, lime, and capping applications, and shows that they decline over time, despite an initial æpH shockÆ to the solids as measured by TAA and CRS in the case of lime. Similar treatment curves were observed for heavy metal leachates. Tree height and vegetative cover density indicated that with increasing acidity in the waste rock dump, the lime and capping options did not allow healthy revegetation, but in the Terra B treated areas tree growth and density were comparable to background, undisturbed forest levels.is needed with respect to tailings management, based on a novel integrated research framework.CITATION:Fergusson, L, Blair, D and Barros, G, 2012. Sustainable waste rock remediation and revegetation - A real-world longitudinal study comparing ViroMine technology to standard applications and doing nothing, in Proceedings Life-of-Mine 2012 , pp 249-258 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 10, 2012

By A. L. Blomfield, M. J. Trott

ThE Golden Cycle Mining and Reduction Co. operates its custom mill at Colorado Springs on Cripple Creek ores exclusively. These ores are straight sulfo-tellurides, with practically no base metals such as Pb, CU, Zn, As, or Sb. Upon entering the mill, the ore all passes through the sampler to storage bins, where beds of 5000 tons each are made to insure uniformity in roasting. Classification of ORes For efficiency, it has been found advisable to separate the ores into two classes according to their lime content. Other constituents have their effect, such as alumina and magnesia, but, speaking generally, these are roughly proportional to the lime, which, as CaO, is used as the indicator. Class A contains not more than 2 per cent. CaO and comprises about 66 per cent. of the ore treated. Class B contains over 2 per cent. CaO, and comprises 34 per cent. of the ore treated. Typical analyses of both classes are as follows: Class A a B Insol.......................... 86.70 75.90 Al2O3........................:.. 2.30 3.40 Fe.............................. 3.26 3.48 CaO............................. 1.57 5.12 S............................... 1.79 1.80 MgO........................... 0.21 1.08 Ignition loss..................... 3.20 6.50 99.03 97.28 The beds of each class of ore are made as large as possible with the available ore as it comes in, to avoid changing from one bed to the other any oftener than necessary. Each roaster will handle 50 per cent. more of class A ore than of class B, with practically the same results. This necessitates changing the rate of feed for each new bed and tends toward a poor roast and loss of tonnage at each change.

Jan 1, 1919

By Mark J. Zdunczyk

"The term “aggregate” has a number of definitions depending primarily on the use of the material. Aggregate in some context is sand, gravel, crushed stone, slag or other material of mineral composition used in bituminous and portland cement concrete, mortar, plaster, railroad ballast, filter beds and a variety of other uses where aggregates can be utilized.Of the natural aggregates, crushed stone is widely used for most construction purposes. Crushed stone can be mined from a variety of rock types such as limestone, dolomite (dolostone), granites, and granitic type rocks, basalt, gabbro (trap rock), sandstones, schist, marble, gneiss, quartzite, rhyolite, as well as other rock types. The U.S. Geological Survey (USGS) breaks down the rocks by type sold as follows: limestone, dolomite, marble, calcareous marl, shell, granite, trap rock (basalt, diorite) sandstone/quartzite, slate, volcanic cinder and scoria and miscellaneous stone.In 2015, the USGS estimates that 1.32 Gt (1.45 billion st) of crushed stone were produced in the United States. The volume of crushed stone produced, and the numerous mines that produce it make the crushed stone industry the largest mining industry in the United States. The five leading states for production of crushed stone in 2015 were Texas, Pennsylvania, Missouri, Florida and Ohio. The size of the first two states certainly helps in output because of the large market area. The remaining states benefit from being able to barge along rivers to outside markets in adjoining states. Georgia producers rail large amounts of granitic aggregate to Florida and adjacent states devoid of crushed stone aggregate, especially skid resistant aggregate (aggregate used on the top course of asphalt roads)."

Jul 1, 2016

By David T. Bunney

In .December of 1987, International Mill Service, Inc. signed an exclusive licensing agreement with Tetronics Research & Development Co. Limited of Faringdon, Oxfordshire., England to commercialize plasma technology which had been demonstrated in an EAF dust processing application. The intent of the process is to reduce and volatize the zinc, lead and cadmium oxides inherent in EAF dust and collect these elements as metals in an ISP (Imperial Smelting Process) zinc splash condenser, and to render the resultant slag an inert, non-hazardous material. With these objectives in mind, IMS started commissioning facilities in 1989 at Florida Steel in Jackson, Tennessee and Nucor-Yamato Steel in Armorel, Arkansas. This paper will address the commercial development and progress of the technology at these two installations. Process Description In the EAF steelmaking process typically the off gas stream is cleaned by some form of baghouse. The particulate collected is known as Electric Arc Furnace dust and has been designated by the U.S. EPA as hazardous waste number K061, once it leaves the collection system. This designation was given to the material due to the high toxic concentrations of lead and cadmium (nickel and chromium for stainless EAF dusts) inherent in the dust. IMS' method of operation is to locate the facilities on the client mill's property adjacent to the baghouse. The dust is transported directly to IMS via a closed conveyance system. This method enables the technology to be an additional processing step in the steelmaking process. Once the dust has been transported to the IMS facility, it is fed, metered and mixed mechanically in the feed conveyance system with a carbon reductant (typically coke breeze). The carbon reductant is approximately 10% of the dust feed rate. This mixture passes through the feed system and enters the furnace

Jan 1, 1992

By Thomas A. Morley

This paper deals with the minimization of ventilation costs for the controlled-flow mine ventilation network. Cost elements considered include the cost of power and the fixed cost of the fans. The problem is modeled in a mixed-integer programming format and solved via the branch and bound method. Computational experience with sample problems is discussed.

Jan 1, 1983

By C. Bailey Williams

Aragonite "sand," an oolitic lime-stone, is distributed throughout the Bahamas on the Grand Bahama Bank, adjacent to Southeast Florida. Bahamian deposits hold 75-100 billion tons of recoverable Aragonite. Aragonite's precipitation from seawater over 700 years ago assures low contaminates, making it a pure material for such industries as cement, glass, etc. A 90-acre, man-made production island was built south of Bimini, adjacent to ocean shipping channels mining is by cutterhead, suction dredge, dewatering, and stockpiling for further drainage and shipping. Aragonite is transferred to the U. S. East and Gulf Coasts via bulk carriers to points of sale.

Jan 1, 1978

By R. B. Nourse, S. F. Gwynn-Jones, S. Nikolic, M. L. Bakker, I. McDougall, H. Joubert

"Tenova Pyromet’s core furnace knowhow and expertise has been built within the ferroalloy and nickel/platinum group metal (PGM) industries with the supply of electric furnaces for a number of nickel/PGM operators, including Eastplats, Lonmin, and Anglo-Platinum in South Africa, Mineraçào Serra Da Fortaleza in Brazil, and Norilsk Nickel in Russia. Tenova Pyromet has also supplied the electrode columns and associated electrode equipment – the heart of the electric furnace technology – for cobalt recovery in furnaces in Zambia and the Democratic Republic of the Congo. The quantity and size of projects undertaken by Tenova Pyromet has provided the opportunity to continuously improve furnace designs and the scope of supply, culminating in the most recent nickel/PGM project currently under construction at Northam Platinum. Through this innovative culture, the Tenova Pyromet Base Metals Initiative was formed in 2015 to develop the Novasmelt™ Furnace; a next generation optimised Top Submerged Lance (TSL) furnace design. The combination of Tenova Pyromet’s advanced Novasmelt™ product with our industry leading electric furnace technology are discussed with reference to applications for nickel and cobalt production. Flowsheet arrangements are compared summarising potential capital savings, operating requirements and achievement of downstream product quality.INTRODUCTION Tenova Pyromet is a leading player in the field of smelting technology development and equipment supply. Tenova Pyromet is the result of the union of three furnace suppliers under the Tenova banner: Techint Technologies (Tagliaferri), Core Furnace Systems Corp (Lectromelt) and Pyromet Technologies. The furnace experience of the combined groups dates back over a century with the earliest Lectromelt going into production in the early 1900s. Throughout the modern era, Tenova Pyromet has developed a reputation for providing dependable innovative smelting technology, high quality equipment and sound project execution to a worldwide client base with customer plants operating in Europe, Southern Africa, North America, South America, Russia, Kazakhstan, the Middle East, South Korea, and India. Tenova Pyromet’s core knowledge and expertise was developed in the South African ferroalloy, base metals, and platinum group metals (PGM) smelting industries. Tenova Pyromet has spent considerable effort on development and has contributed significantly to improve the state of the smelting industry. Tenova Pyromet’s electrode columns have become widely renowned and are now providing significant benefits, especially in increased furnace availability, to many smelting furnace operators. The electrode column is the heart of the furnace as it delivers a controlled amount of electrical energy, at an optimum depth in the burden/bath, to the smelting process. Every furnace is custom designed to the specific operating range and optimal operating point of that furnace and process"

Jan 1, 2017

By Read T. A

PART 1The quantity of dust present and the methods used for suppression of dust in metalliferous mines has, in recent years, received considerable attention from mining engmeers in various parts of the world. Shortly after the publication of the General Report of the Miners' Phthisis Prevention Committee, South Africa, in 1916, the officers of the Broken Hill South Limited started investigations into the conditions of the dustiness of the air in the underground workings. As the methods used are not generally known in Australia, the writers are of the opinion that the present is an opportune time to place them before members of the Institute. A large amount of the subject matter of this paper has been drawn from the 1916 and 1919 reports of the Miners' Phthisis Prevention Committee, South Africa, the paper of Mr. Innes published in "The Chemical, Metallurgical and Mining Society of South Mrica"; also various articles appearing in the Journal of Industrial Hygiene, and the American Journal of Public Health. A great deal of research work into the cause, prevention and estimation of mine dust has been made by the Miners' Phthisis Prevention Committee of South Africa, and officials of the United States Bureau of Mines. The writers considered it advisable to begin the investigation at the South Mine with apparatus and methods developed by the South African Committee.Through the Australian agent of the Cape Explosives Company, inquiries were made preliminary to procuring the necessary apparatus for the determination of dust, from South Africa. The writers then learned that the older gravimetric method used by the Phthisis Prevention Committee was likely to be superseded by the konimeter...

Jan 1, 1922

By Hubert E. Sherer

The mining industry is presently one of the most heavily capitalized industries in the U.S. (U.S. - Statistical Abstracts, 1979). U.S. sales of new mining equipment (not including environmental, preparation, or long distance transportation equipment) are projected to reach approximately $5 billion/year in 1980 (Frost and Sullivan, 1979). Of these new equipment sales approximately 30 to 40 percent of this equipment will be used to replace old equipment. Therefore, an increase of efficiency in the use of equipment replacement capital could have substantially positive effects for the U.S. mining industry. This is very critical in these times of restricted capital availability, double digit inflation, burdensome governmental regulation, and rising foreign competition in the mining industry. This paper examines the numerous factors that constitute the typical mine equipment replacement problem. A computerized, mathematical model is formulated to utilize historic cost and production information to predict equipment cost versus age for the existing and potential replacement machines. Another part of this computerized model determines the best equipment replacement strategy that accomplishes estimated production goals at a minimum discounted cost. This computerized model is an easily used, consistent method of determining the optimum replacement age for any equipment unit or fleet of equipment at a mining operation.

Jan 1, 1982

By C R. Ferrari

Residual subsidence is generally accepted as being about 5% of the total subsidence occurring within 12 months of all mining finishing. This paper looks at five case studies from different parts of the country, in various mining settings within a depth range of 430m to 760m. From a single seam single panel working to working the eleventh seam, all are within the concealed coalfield, similar to today's mining. The monitoring of subsidence continued for many years once the mining had finished and the results obtained are at considerable variance from the accepted norm. Subsidence has been found to carry on for up to eleven years after mining has ended, within a range of 8% to 45% of total subsidence. A highly significant factor was that subsidence, as a whole, was generally much more than predicted. The residual subsidence aspect has to he viewed in this context and in order to debate the subject at length, the causes of residual subsidence have to be balanced against the apparent inability to accurately predict subsidence. The results from the case studies were similar, even though the mining settings differed considerably. Subsidence of around 10% to 20% continued for several years after mining had ceased.

Jan 7, 1997

By D M. Silva, J C. Alves

According to the literature, material transportation represents 50 per cent of the operating costs for an open pit mine. In this context, this paper proposes a multistage approach for dynamic truck dispatching in real open pit mine environments, implemented in the commercial package SmartMine®, marketed by Devex SA. The first stage of this approach defines the optimal number of trucks that maximises the tonnage production by means of a robust linear programming model, which considers the operational constraints of a real mining process. The second stage uses a dynamic dispatching heuristic joining computational simulation and multicriterion optimisation techniques for decision making for truck dispatching. Another relevant contribution of this work is the publication of realistic instances collected from a dispatching system managing an iron mine, containing information about the hauling and loading fleet, the equipment situation when the working shift starts, cycle times, the time line of special occurrences (such as equipment stoppages and loading equipment reallocation in order to satisfy the mine planning) and the tonnage produced. These instances were generated with the purpose of submitting the method to the test of a real situation that considers the uncertainties existing in the process studied. The proposed approach was validated by means of a discrete event simulation model applied to the previously designated instances. Using this multistage approach as a mechanism for dispatch decision making, it is shown that the haulage fleet productivity increased when compared with the real values reported from the instances. These results are important because they show that the proposed approach generates efficient dispatch decisions for trucks operating in a real environment, reducing operating costs, increasing production and making the mine more competitive.

Sep 26, 2011

By D. D. Runnells

In order to establish meaningful remediation goals and monitoring programs in areas disturbed by mining, it is desirable to determine the natural metals concentrations that existed in the area prior to mining. At Iron Mountain, California, several natural sources exist for acid drainage and loading of metals to Slickrock and Boulder Creeks. This paper describes methods to determine the contribution of copper and zinc to groundwater and surface water from those sources, including natural gossan rock outcrops, mineralized bedrock, and colluvial materials. Methods used include evaluation of: 1) historical information, 2) literature values of unmined, mineralized areas, 3) analyses of water from monitoring wells, 4) leaching studies, 5) statistical analysis, 6) isotopic studies, and 7) identification of background by elimination of mining sources. Results from this natural background determination show that Boulder Creek and Slickrock Creek carried elevated concentrations and loads of copper and zinc prior to mining activities. With repeated rinsing of reclaimed and remediated mine materials by rainfall, there will be a diminishing contribution from residual waste rock and tailings at Iron Mountain, and natural background will become an increasingly larger proportion of the total load.

Jan 1, 1999

By L. Xu

Since the establishment of the standard dust concentration of 2 mg/m3, a strong effort has been made by mining engineers and researchers to provide better dust control equipment and procedures for underground coal mines. Particular areas of success have been control of dust generation by better coal-cutting strategy, better design of water sprays for dust suppression and air movement, use of scrubbers, and improved design of face ventilation systems. A drastic improvement occurred over time such that the average dust concentrations for continuous miner operators dropped from 6.5 mg/m3 in 1968 to 1.3 mg/m3 in 1980 and for auger, cutter, longwall, and roof bolter occupations from 2.7 mg/m3 in 1973 to 1.6 mg/m3 in 1980 (Niewiadomsky, 1983).

Jan 1, 1990

By Howard E. Parkinson

In 1969, new coal mine health and safety legislation was enacted in the United States. As a result of this legislation, the Department of Interior, Bureau of Mines has carried out communications research aimed at developing whole mine communications for increased safety and efficient operation. The research has advanced and many promising results are now being demonstrated to the mining industry. However, there remains a challenge to further improve wireless communications within the mine workings, and through the overburden above the workings. The objectives for future research and development will be discussed, together with the physical and operational constraints that new mine communication systems must face.

Jan 1, 1973

By Maidl B

A tunnel operations analyser is a new high technol- ogy instrument for use in underground work. By remotely sensing the acoustic emissions from operating machines and processes in a tunnel or shaft and by applying sophis- ticated computer processing to them individual process cycles and other detailed information about the operating processes can be collected. Detailed analyses and dissec- tions of the work in progress can be made and a variety of action oriented management reports produced. The pro- cess is fully automatic. Results of applying this device to two full scale tunnel projects are presented. The hardware and software that comprise the instrument are discussed in detail. Processes by which this device can be used to sub- stantially reduce tunnel costs are presented. It is concluded that this type of technology has great potential.

Jan 1, 1987

The Barmac autogenous crushing mill is one of the most successful new comminution technologies to become available to the mining and industrial minerals industries in this decade.The Barmac autogenous crushing mill is an innovative Vertical Shaft Impactor which operates in essence like a high intensity dry ore centrifugal pump with the reduction occurring primarily as a result of high velocity rock to rock impact in a fully rock lined crushing chamber. With applications in a wide range of mining and industrial minerals operations the Barmac autogenous crushing mill presents an opportunity to enhance reduction and liberation whilst providing many cost savings and production increases in new and existing plants.This paper briefly describes the operation of the Barmac autogenous crushing mill and reviews its benefits.

Jan 1, 1990

By Donald M. Liddell, G. C. RIDDELL

THE cosmic ray continues to engage the attention of the physicists, and according to Millikan and Compton, experiments of the past summer indicate that these rays must come from interstellar space, but not from the stars themselves. According to press reports of the International Congress of Physicists at Rome, the view was given there that these rays have an initiating potential of over 750,000.000 volts. In the field of spectrographic investigation great strides have been made. The U. S. Naval Research Laboratories (R. F. Mehl and G. E. Doan of Lehigh) have just finished a year's work with a "radium torch" or "shadowgraphic apparatus" in the field of the X-ray, that bids fair to displace the latter to a great extent. The torch is more powerful., easier to operate and cheaper. Penetration of 10 in. of steel has been accomplished, which. is much -beyond the- -scope-, of the X-ray..

Jan 1, 1932

By Dilermando Nagle Travessa

High strength-light weight materials are very attractive for the transportation sector, particularly to the aerospace industry. High strength-age hardenable aluminium alloys are widely used in airframes due to their unique combination of strength, density, toughness, corrosion resistance, cost and easy processing. However, the hardening capacity of such alloys is somehow saturated due to thermodynamic issues related to the conventional processing. The production of aluminum-matrix composites is a promising strategy to overcome this limitation, resulting in strength levels that cannot be reached by actual commercial aluminum alloys. In the present work, multiwall carbon nanotubes were used to reinforce the AA6061 aluminium alloy. 1 and 2% weight percent of MWCNT were mixed to the alloy powder by high-energy ball-milling process. The blended powder was consolidated by hot extrusion. The obtained composite bars were submitted to heat treatment for the T6 condition in order to combine both CNT dispersion and precipitation hardening effects. Optical and scanning electron microscopy, as well as hardeness testing, was used to characterize the bars. Typical wrought microstructure, free of defects, was observed on the extruded bars. Hardness of the composites was observed to increase by 20, 28 and 68% for 1% MWCNT 6 h milling, 2% MWCNT 6 h milling and 2% MWCNT 10 h milling, respectively, in the as-extruded condition. The better performance for the composites blended at higher milling time was attributed to a better nanotubes dispersion. Subsequent heat treatment to the T6 condition did not result in additional hardening.

Aug 8, 2018

By Eugene Frey

"INTRODUCTION The ti taniferous-iron deposits in the Iron Mountain area of the Laramie Range, and particularly the Shanton deposit, were examined by several engineers. 3/ of the Bureau of Mines during 1942, 1943, and 1944. A dip-needle survey also was made early in 1945. 4/ Interest in this property has increased as a result of the exploratory work completed by the Bureau in 1944 on the Iron Mountain deposit, 6 miles northeast of the Shanton property.ACKNOWLEDGEMENTSIn its program of exploration of mineral deposits, the Bureau of Mines has as its primary objective the more effective utilization of our mineral resources to the end that they make the greatest possible contribution to national security and economy. It is the policy of the Bureau to publish the facts developed by each exploratory project as soon as practicable after its conclusion. The Mining Branch, Lowell B. Moon, chief, conducts preliminary examinations, performs the actual exploratory work, and prepares the final report. The Metallurgical Branch, R. G. Knickerbocker, chief analyzes samples and performs beneficiation tests. Both these branches are under the supervision of Dr. R. S. Dean, assistant director.Special acknowledgment is due to Paul T. Allsman, chief, Salt Lake City Division, Mining Branch; James A. Marsh, district engineer; Paul E. Pesonen, Frank L. Wideman, and Frank H. Gunnell, Bureau of Mines engineers; and to S. R. Zimmerley, chief, Salt Lake City Division, Metallurgical Branch, for analyses of samples."

Aug 1, 1946

It has been reported previously that dolomite samples from different locations showed varying flocculation behavior with Poly(ethyleneoxide) (PEO). In this study it is determined that palygorskite associated with the Florida dolomite samples is responsible for their flocculation with PEO. A detailed characterization of the dolomite samples from different locations and its relevance to flocculation with PEO is discussed.

Jan 1, 1994