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By R. E. Head

[Surveys of the manganese situation conducted by the Geological Survey any other agencies have definitely established the, fact that the tonnage of high-grade manganese or in the United States is relatively small. It is therefore obvious that large-scale production of manganese is possible only through beneficiation of low-grade material. Deposits of low-grade manganese ore are being examined by engineers of the Mining Division of the Bureau of Mines to determine their size and possibilities as sources of manganese on a tonnage basis. The Metallurgical Division of the Bureau is developing and perfecting beneficiation processes with the objective of utilizing such low-grade ores. Microscopic study of these ores represents one phase of the research.]

Jan 1, 1941

The Institute has set important objectives for 1988 to make the Institute still more purposeful. Precious metals The Second International Symposium on Mining, Extraction, and Processing of Precious Metals will be held in Las Vegas, Nevada, USA, during the 118th TMSAIME Annual Meeting in March 1989. The First International Symposium on Precious Metals.

Jan 1, 1987

By R. E. Head

[Surveys of the manganese situation conducted by the Geological Survey and other agencies have distinctly established the fact that the tonnage of high- grade manganese ore in the United States is relatively small. It is therefore obvious that large-scale production of manganese is possible only through beneficiation of low-grade material. ]

Jan 1, 1941

By S Sondashi, F. J. Chidley, W. A. Grobler

Some of the challenges facing the flotation of base metal sulphides are the opening of new and varying ore bodies as well as maintaining essential skills in plants. Flotation reagent research focuses not only on improving flotation grade and recovery, but also on producing reagents robust enough to cope with changes. A group of recently developed co-collectors, activators, depressants and frothers are described together with a summary of results measured on base metal sulphide ores.

Jan 1, 2005

By G. V. Sullivan

This report summarizes the results of a preliminary study concerning manganese extraction from low-grade dolomitic materials from the Philipsburg district in Montana by the Dean-Leute ammonium carbamate process. Studies were made to determine the relationship between the variables involved in treating these materials by a roast-leach process and the amount of manganese extracted. The variables studied were the roast temperature, the roast particle size, the molar ratio of NH3 to CO2 in the leach solution, the liquid-solid ratio in leaching, the leach time, and the size of the particles being leached. The roast-leach studies were statistically designed, and the experimental results were evaluated by an analysis of variance.

Jan 1, 1962

By James R. Garvey

The impact of conversion on the coal industry can be summarized very briefly: We are going to have to mine an awful lot of coal. Fortunately, the United States has the coal reserves available, and given the right conditions, we can mine it. The coal reserves of the United States are enormous. If we consider them on the basis of proved reserves, using the standards of the petroleum industry--that is, resources mapped and explored and recoverable with present techniques at close to present costs--and compare that with the reserves of other fuels, coal constitutes 88 per cent of the proved recoverable energy resources of the nation. That includes oil, natural gas, oil shale and uranium, so long as the uranium is used in burner reactors. If we consider resources on the basis of "ultimate recoverable" reserves, that is, those resources which can be extracted with improved technology and at somewhat higher costs--and if we include those resources of all fuels not yet found but believed to be waiting discovery--coal still accounts for 74 per cent of the national total. We have built a hydrocarbon economy in which about 76 per cent of our total energy needs are supplied by petroleum and natural gas, and about 20 per cent by coal. Domestic resources of oil and gas are running dangerously low and, assuming a continued hydrocarbon economy, the 20 per cent supplied by coal may increase dramatically. We already import nearly a quarter of the petroleum we consume, and the chief source of additional imports seems to lie in the politically unstable Middle East. Natural gas is in even shorter supply, and the problems of importing it seem at least as difficult as those of oil. The fact is, the United States is already relying to an increasing extent on foreign fuel sources. There is an obvious national risk in making an important part of energy supply hostage to foreign governments of uncertain tenure and friendliness. There is also an economic risk--one of the chief reasons for last year's economic freeze was to try to correct the deficit in our balance of payments; it is obvious

Jan 1, 1972

By J Jardine

An improved ground support method for development intersections, wide spans and stope brows was implemented at Kanmantoo mine. The method uses a jumbo to simultaneously drill and install self-drilling anchors (SDAs) to depths from 4.5 m to 7.0 m. Resin is subsequently pumped into each SDA using a specially designed integrated tool carrier basket, with plating occurring within 10 mins due to rapid resin cure. This methodology means that SDAs can be installed rapidly due to reduced process steps and wait times with reduced hazards to personnel. Cablebolts are used extensively in underground mines to reinforce the ground in wide spans, such as at intersections and stope brows. The flexible cablebolt tendon allows for a long, continuous and high-capacity reinforcing element to be inserted into the rock. A common cablebolt installation practice at Australian underground mines that do not utilise a mechanised cable bolter, is for cablebolt holes to be drilled by a jumbo or longhole rig, hand installation and grouting by a service crew, then plate tensioning following a grout curing wait time of typically 12 to 24 hours. This process involves multiple separate labour-intensive work processes and results in reduced availability of priority headings. This paper discusses the development history of vertical SDA use in wide spans at Kanmantoo mine. The installation process is fully described, including aspects such as reliable in-hole coupling of SDAs, resin selection and pumping aspects. A cost benefit assessment, and a case for ground stability are presented to compare cablebolt use to SDAs in development intersections.

Mar 29, 2023

By J. H. Kim

Since the Hardy Cross numerical algorithm was applied to the solution of mine ventilation networks, there have been numerous developments in ventilation network analysis procedures. The Newton-Raphson method, the linear theory method, and the second-order approximation method are three of the additional approaches that have been applied. The efficiency of a ventilation network analysis procedure depends not only on the method of solving the system of equations derived from ventilation networks, but also on the method of deriving the equations through selection of the meshes. This paper investigates the impacts of three mesh selection methods on the efficiencies of four ventilation network procedures. The minimum-resistance spanning tree method is the most popular procedure for selecting meshes. The shortest-path method was suggested by Epp and Fowler (1970) for improvement of the Newton-Raphson method. The minimum-resistance-path method is suggested here as the third method of selecting meshes. The effects of these three methods on the Hardy Cross method, the Newton-Raphson method, the linear theory method, and the second-order approximation method are analyzed in this paper. These network analysis methods have been summarized in the paper by Kim and Mutmansky (1991).

Jan 1, 1992

By J. Drelich

An improved experimental procedure to measure contact angle has been consolidated with coal surface preparation involving polishing with abrasive paper, alumina powder, and a cloth, followed by ultrasonic and mechanical cleaning. Specifically, the captive-bubble measuring technique has been compared with the sessile-drop technique and the former has been recommended for the examination of the hydrophobic properties of coal surfaces. Results of the research program, which is currently under way, on the examination of the effect of the nature, amount, size and distribution of mineral inclusions in coal on its wettability are briefly reviewed.

Jan 1, 1999

By Yi Yang, CHENGLONG XU, HAORAN LI, YALI FENG, JINRONG JU

This study presents a method for recovering valuable metals and synthesizing anhydrite from steel slag using sulfuric acid leaching and solvent extraction. The process achieved high leaching efficiencies for V, Ti, Fe, and Mg, and produced anhydrite with 93.09% purity. The leachate was further processed to separate and recover V, Ti, Fe, and Mg using selective stripping and precipitation methods, offering a sustainable approach to steel slag utilization.

Jan 22, 2022

By D. M. Maijer, S. L. Cockcroft, S. Modak, A. B. Phillion

"A comparison between hydrogen-diffusion-based micro-porosity formation and growth behaviour of two important aluminium foundry alloys, B206 (Al-Cu) and A356 (Al-Si-Mg) is presented in this paper. Specifically, the predicted pore size and pore fraction distribution of these two alloys resulting from directional solidification and identical hydrogen concentration are investigated numerically based on a model proposed by Yao et al. (2011. Met. & Mat. Tran. A. 42A, 4137–4148). This model takes into consideration the initial hydrogen content in the melt, the cooling rate, the partitioning of hydrogen between the solid and liquid phases, and the evolution in solid fraction with temperature. Due to different alloy chemistries, the activity of hydrogen in B206 and A356 are quite different, as are the solidification range and the resulting solidification microstructure. Being a primary alloy, B206 has dendritic microstructure and solidifies over nearly 135°C (505–641°C), whereas A356 contains fifty percent eutectic microstructure, and solidifies over 80°C (533–613°C). This allows a very different behaviour of micropores i.e. the effective pore radius in B206 is quite a bit lower as compared to A356, as is the pore number density. The evolution of local hydrogen concentration in liquid metal is analysed and compared for both the alloys.INTRODUCTION Over the past decades, the demand for materials with enhanced strength-to-weight ratios has significantly increased in the aerospace and automobile industries in order to improved fuel efficiency. For many automotive components, particularly shape castings, the trend is towards replacing ferrous alloys with aluminium alloys. The increase in the use of Al is primarily due to its low density, about one-third that of steel, and its relatively good strength that allows for weight reduction without reducing performance. Presently, Al-Si based alloys (e.g. A356) are the most prevalent due to their good mechanical performance in strength-to-weight ratio and excellent castability (Atwood et.al., 2000). However, superior mechanical properties can be achieved using Al-Cu alloys. For example, the alloy B206 offers a higher strength while retaining excellent ductility (Poirier et.al., 1987)."

Jan 1, 2017

By Julian Malnic

The emerging marine minerals exploration and mining industry is currently focused mainly on the technical elements for its success such as developing exploration and mining technologies. However, in one sense, the technical challenges are quite soluble whereas those arising in the fields of the environment and public opinion could present this new generation of miners with problems that are far more difficult to overcome. One need only look at the issues currently faced by mining projects on land to see how powerful the new forces of so-called ?civil society? are in stopping mineral developments in many countries. From the geographic viewpoint, there are many countries but there is just one ocean, so the impacts experienced by any one operation are likely to have pervasive repercussions throughout the industry. A well-oiled NGO development protest lobby will see leverage in resisting this new industry and will seize on the single-ocean angle. The Australian Minerals Industry has established a voluntary Code for Environmental Management that provides an active and valuable model for satisfying the ?court of public opinion? and in delivering economic results to industry that are in current jargon, sustainable. An explanation of the Code for Environmental Management, and the reasons behind 44 companies representing more than 300 operations and 85% of Australia?s sizeable mineral production being signatory to it will be given. Participants see it as a means to future shareholder wealth.

Jan 1, 2000

By J. Drelich

The wetting behavior of liquid polymers at solid surfaces and the adhesion forces involved at polymer-filler interfaces should always be considered in the fabrication of high quality polymer composites, including those made with mineral fillers. Spontaneous polymer spreading over the filler surface is a basic condition in the fabrication of the polymer-mineral composites. In this regard, the wetting and adhesion characteristics of polymer-mineral systems are reviewed in this contribution. It appears that several aspects of wetting phenomena at mineral filler surfaces are not well described in the literature and require further systematic study. Specifically, it is clear from this review that efforts should be made to determine the effects of mineral surface contamination (including surface hydration) on wetting and adhesion phenomena, and to determine the wetting characteristics of molten polymers at mineral filler surfaces. It is expected that any improved fundamental understanding of wetting and adhesion phenomena for the polymer-mineral composites will provide the basis for further technological development.

Jan 1, 1995

By Carlton H. Baab

In June, 1981 the Electric Power Research Institute (EPRI) issued a report titled "Control Systems in Coal Preparation Plants" to determine the status of instrumentation and automation systems in the coal preparation industry. EPRI concluded that the control systems presently being employed in the U.S. coal preparation plants "are relatively primitive compared with those in other mineral processing industries; and analytical instrumentation is virtually non-existent". Until recently, clean coal has had a low selling price and satisfying the purchasers' specifications required only minimum cleaning. However, it is becoming more apparent that the increases in coalfired utility power plants forced outage rates are relative to the deterioration in the quality of fired coal. Utility companies are becoming aware of the economic value of reducing the variability of ash, moisture and sulfur in steam coal purchase orders. New contracts are currently being negotiated between electric utilities and coal producers that include provisions for increased penalties if the product does not meet specifications. With tighter specifications on the quality of steam coal, interest is increasing in more sophisticated control systems. One type of device that is currently assisting the preparation plant operator optimize and control the coal cleaning process is nuclear based instrumentation. Nuclear instrumentation includes methods for measuring weight, level, and density as well as for performing elemental analysis on coal. This paper discusses the various types and applications of nuclear instrumentation currently in use in the coal preparation industry.

Jan 1, 1983

By D. Berkley

The competitive pressure, the increasing energy costs and the environmental regulations impose substantial challenges to the definition of power plants serving industrial facilities. Primary mining and metallurgical facilities have even greater challenges because they are often located remotely, where the fuel supply can be a problem. The absence of a power grid imposes challenges on the reliability and quality of the electrical energy supply. In addition, the facilities usually require thermal energy too, not only electricity. This paper outlines these types of issues that have to be considered when defining a cogeneration plant integrated with a remote located industrial facility. It is addressed to the ?users? of cogeneration facilities rather than to ?generators.? The focus is on analyzing various site-specific design considerations to pre-screen the feasible cogeneration alternatives and minimize the number of options to be analyzed from the economics viewpoint. This approach could substantially reduce the engineering effort and schedule during the feasibility phase of the project. Part 1 of this paper (Berkley, 2003) provides a basic understanding of cogeneration plants of various types to establish a common language. Part 2 outlines and analyzes specific issues that could be of help in the definition of cogeneration installations for remotely located industrial facilities, with a focus on mining and primary metallurgical plants.

Mar 1, 2003

By Charles E. McCarthy

Part 1 of this report is concerned with the electric-furnace production of calcium aluminate and iron alloy from a variety of siliceous ferruginous ores of aluminum. The furnacing research was directed, first, to determine the extent of the field in the CaO-Al2O3-SiO2 system, in which calcium aluminates with the optimum leaching characteristics are obtained; second, to produce suitable quantities of these aluminate mixtures for pilot-plant leaching tests; third, to investigate the physical chemistry of the reduction reactions during furnacing; and, fourth, to study the economics of the process. The third and fourth steps were not completed. Part 2 comprises another phase of the work and will appear as a second Report of Investigations. It deals with the extraction of metallurgical-grade alumina from the calcium aluminate slag produced in the electric furnace and includes the following steps: leaching, desilicating, precipitating, dewatering, filtering, and washing of the aluminum hydrate. No claim is made that the data are complete, nor has the chronological order of obtaining data been followed. Rather, it is emphasized that additional work is necessary if the full possibilities of the process are to be evaluated. and made available.

Jan 1, 1949

By J. B. Hadaway

The operation at Phu Kham commenced design and construction in early 2006 and was commissioned in May 2008. This paper will examine and discuss the project from the inception of flow sheet development and equipment selection, equipment design and manufacture, construction, commissioning and ramp up to full production. The paper will touch on the strategies employed to achieve a short schedule and the efficient use of capital, but with the main emphasis on the grinding circuit. Various challenges during the early years of operation will be discussed including the effect of ore characteristics, including competency, on the performance of the grinding circuit. Actions to overcome these challenges and to enhance performance will also be discussed. Finally, current and future plans to improve the performance of the grinding circuit and the overall plant will be summarised.

Jan 1, 2012

By Andrew Middleton, Mick Stadter, Chris Crowe, David Chong

"The Level Crossing Removal Project – Package 1 is part of the Victorian Governments commitment to remove 50 of the most dangerous and congested level crossings across Melbourne. This involved removing three crossings on the Frankston Line in the south east suburbs of Melbourne. The works involved replacing approximately 2.5km of at grade track with three rail cuttings up to 8 m deep at each of the bridges that replace the level crossings. The cuttings are retained by piled retaining walls and during the main construction occupation approximately 250,000 cubic metres of soil was removed. The project has presented significant geotechnical challenges due to the location in residential suburbs and tight rail corridor and rail occupation timeframe. These challenges included temporary and permanent wall stability, foundations, earthworks and dewatering. As a result, careful design and innovative construction techniques have been necessary to limit impacts on the community and meet the project timeline.INTRODUCTIONThe Level Crossing Removal Project – Package 1 is part of the Victorian Governments commitment to remove 50 of the most dangerous and congested level crossings across Melbourne. This involved removing three crossings on the Frankston Line where it crosses North Road in Ormond, McKinnon Road in McKinnon and Centre Road in Bentleigh.The project involved replacing approximately 2.5km of at grade track with three rail cuttings up to 8 m deep at each of the bridges that replace the level crossings. The cuttings will accommodate three lines of rail tracks with the cuttings up to 25 m wide. The cuttings are retained by piled retaining walls and during the main construction occupation approximately 250,000 cubic metres of soil has been removed.The project presented significant challenges due to the location in residential suburbs and tight rail corridor and rail occupation timeframe. As a result, careful design and innovative construction techniques have been necessary to limit impacts on the community. The geotechnical challenges generally fell into one of three areas, earthworks, structures and groundwater. The primary earthworks challenge for the project was moving the 250,000 cubic metres of soil in a 10 day window, however, from a geotechnical viewpoint, obtaining a stable subgrade on which to operate the necessary construction plant in a short time frame with constrained site access and time to import materials was the key. Whilst closely watching the performance of the dewatering system, a range of contingency plans were developed to cope with any difficulties."

Jan 1, 1900

By Ronald H. Church

As part of the Bureau of Mines health and safety research program in strata control, a ground-penetrating radar (GPR) system capable of pene-trating approximately 10 ft into the mine roof has been devised to identify anomalistic conditions. The GPR system consists of a transmitter with carrier frequencies of 250, 500, and 1,000 MHz, utilizing a dipole antenna, and a receiver, consisting of a dipole antenna fed into a sampler with a time base housed in a storage oscilloscope. A computer was utilized for data acquisition and data processing. Data analysis by computer enhancement revealed recognizable return ra-dar signatures from the middle man rock and main roof of the test site. These stratigraphic anomalies can be cataloged for recognizable fea-tures, which from the past history of the mine may have been shown to create strata control problems. Early recognition of such features could lead to immediate corrective actions and result in the saving of lives.

Jan 1, 1985

J. A. Mathews,* Syracuse, N. Y. (written discussion?).-It is interesting to note how frequently we hear of some process that is going to revolutionize the tool-steel business. I don't know why it is, but every one seems to have it in for us poor tool-steel men. About 15 years ago, a good-sized plant was built in Syracuse for the manufacture of cast tools of malleable iron. The promoter of the scheme claimed to have a secret, process that had been given to him by a tramp to whom he gave a lift along a dusty road. The widows and orphans invested liberally in the securities of the company without consulting the men established in the machine-tool business in Syracuse. About two years later, when the sheriff's sale occurred, the secret, which was carried on the books of the company as an asset valued at $2,000,000, brought $15 at auction. A little later another concern started on the theory of replacing scrap high-speed steel with new high-speed steel tools made therefrom. All the tool-steel companies have made a practice of purchasing high-speed

Jan 5, 1919