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By C. Chapman, M. G. Reading, M. P. Amsden

Computer control of flotation at the Ecstall concentrator By M. P. AMSDEN, C. CHAPMAN, and M. G. READING Ecstall Mining Limited, a subsidiary of Texas Gulf Sulphur Company, operates the Kidd Creek Mine, a 10000 tons per day base metal producer, near Timmins, Ontario. Two different types of ore are mined and milled: copper-zinc and silver-lead-zinc. At the highly automated Ecstall concentrator the ores are processed by selective flotation in three individual circuits. One of the most important metallurgical tools for process control is a sample system incorporating continuous on-stream X-ray analysis. Recently this system was automated further by the addition of computer control of reagents for two copper-zinc flotation circuits. The computer programs, utilizing optimum seeking methods and smelter contract terms, have increased copper recovery by 1,1 per cent, zinc recovery by 1,4 per cent, and have reduced reagent costs by 16 per cent. Although not expected, copper and zinc concentrate grades were improved slightly as well.

By D J. Brake

In most underground mines, the ventilation system is a significant portion of the total mine capital and operating cost and the largest consumer of underground electrical power. The effectiveness of the ventilation system has a major bearing on the safety, health, comfort and morale of underground personnel, and has a critical role in meeting production targets and therefore business revenue. Perhaps the most important component of the primary ventilation system is the primary fan. Correct performance testing of the primary fan during the warranty period is important not only to ensure the mine has obtained the asset that it paid for and can therefore deliver on the fanÆs crucial safety and economic role in the future of the mine, and to provide a justification for releasing final performance warranty payments to the supplier, but also to provide a benchmark or baseline against which to assess future performance issues. As there are at least three potential international standards available to measure fan performance, there has been considerable confusion regarding which of these to use for testing primary mine fans, and also the correct allowances and tolerances to use. This paper provides guidance on which standards to use for different applications, how the standards should be interpreted, what allowances and tolerances are reasonable, and other important issues to be resolved with the fan supplier prior to making a contract award. The paper also discusses practical issues and methodology for in situ primary fan performance testing.CITATION:Brake, D J, 2013. Performance and acceptance testing of main mine ventilation fans, in Proceedings The Australian Mine Ventilation Conference , pp 141-148 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

A great part of the research on froth flotation of gold ores deals with ores containing gold associated mainly with sulphides, resulting in a largely accepted view that what takes place with sulphides (eg pyrite) in a flotation cell also happens to gold particles. This paper is concerned with the influence of some inorganics (CuSO4, CaO and NaCN) on gold particles flotation, using ethyl or amyl xanthates as collectors. The bench-scale tests were carried out with ground quartz and gold particles mixtures. Some findings stemmed from this study: flotation of the gold particles of size 0.16 mm was efficient adding only frother; larger gold grains were better recovered by the use of stronger collector CuSO4 did not seem to be an activator for gold; the addition of NaCN up to 200 g/t or CaO up to 2000 g/t did not depress the gold grains when amyl xanthate was used as collector although with ethyl xanthate the gold depression was verified.

Jan 1, 1993

By James Yancik

The Howe Coal Co. is mining the Oklahoma Lower Hartshorne bed which ranges in seam thickness from 38 to 42 in. and pitches approximately 7° to the northeast. The raw feed to the cleaning plant averages about 20% ash and 1.10% sulfur, being reduced in the cleaning process to 4.8% ash and 0.9% sulfur with a free swelling index of 8 or 8%. This coal rivals the Pocohantas seam in chemistry and coking characteristics but has better fluidity than the Pocohantas seam coal. The coal is presently being prepared for the Japanese steel market in an 85-tph pilot plant designed and constructed by Roberts & Schaefer. The cleaning-plant flowsheet is discussed in detail.

Jan 1, 1972

By Robert N. McIndoo

A good tire program must begin at the top; management must have an awareness of the tremendous potential for cost saving that tires represent. At Reserve Mining Co., tires account for 33% of the cost of maintaining its 44 tractor-trailer side-dump haulers and 22% of its 32 rear-dump trucks. In comparison, engine overhauls account for only 6% of the maintenance dollar. Doubling the present engine life would save only 3%. The open-pit mine, located near Babbitt, Minn., moves about 46 million t/y with its off highway fleet. Mine roadways total in excess of 160 km (100 miles) and about 1200 tires are in active use at any given time.

Jan 3, 1978

By M. Ericsson

The extractive industries consist of five major sectors: - Mining equipment and services - Dimensional stone - Industrial minerals - Aggregates - Metal mining These industries produce some finished goods but mostly semi-finished products as they feed into other industrial sectors: Basic metals, fabricated metals, construction, chemicals, dyes and pigments, inorganic chemicals, fertilizers, rubber and plastics and non-metallic mineral products. These are the major down-stream industries in this study. Taken together with the extractive industries they form the mineral resource based cluster. The mineral resource based cluster is a substantial part of the Finnish economy: It employs 211 000 persons, 39% of the number of employees in industry. The cluster?s exports account for 20% of industry exports. Value added is 34% of total value added in industry. Investments reach 35% of total industry investments.

Jan 1, 2003

By Donald W. Peters

The 191 million acres of public lands that are managed as National Forest System Lands contain extensive geologic habitat for over 40 industrial minerals. The Forest Service actively encourages exploration for and development of industrial mineral deposits within the National Forests. However, due to competing interests, the Forest Service may not always be able to accommodate industry needs. In order to successfully compete with ever-increasing demands for all resources in the 1990's, industry needs to become more active in public involvement and education and in communicating its contributions and needs to public land managers.

Jan 1, 1991

By Fang-tu Wei

The purpose of developing this system is to monitor the operating status of the fully mechanized mining system in order to raise it's reliability. The completely mechanized coal mining system is a complex dynamic system, involving many sub-systems. It is the key of the mining process as well as a connected system composed of each working procedure. Any hitch in breaking, loading or transporting will interrupt the mining process. The analyses of the operating data has proved that the reasons causing the interruption of the extracting processes mainly come from the inner of coal face. Hence, after the installation of the MINOS system in England, the delays of belt conveyor sub-system were reduced. But the production increment was not as much as expected.

Jan 1, 1986

By M. R. Bowie, J. M. Barker, J. S. Hingtgen

Techniques of testing perlite require a combination of art and science. The modifications made to the perlite Corp. vertical laboratory furnace include addition of instrumentation, flowmeters, vibrators, automatic feeders, and regulators. The basic testing sequence consists of expanded density, furnace yield, compacted density, percent sinkers, and compaction resistance. These tests are modified versions of those specified by the Perlite Institute. This sequence is designed as a preliminary evaluation of a material's suitability for horticultural-aggregate end uses rather than a detailed measure of filtration capability.

Jan 1, 1988

By Kadri Dagdelen

The definition and shortcomings of traditional cutoff grades are discussed. . The concept of optimum cutoff grade policy which maximizes the Net Present Value (NPV) of annual cash flows coming from a mining project is introduced within the basic framework outlined by K. F. Lane. Several examples are used to demonstrate the shortfalls of cutoff grade policies obtained by various heuristic optimization techniques. An algorithm to obtain an optimum cutoff grade policy which maximizes the NPV of a project is given and described in detail.

Jan 1, 1992

The Geograph is a revolutionary seismic system involving special techniques in combining the use of FIT magnetic tape with shock wave echoes created by a weight dropping system.The idea of- weight dropping as a- source of seismic energy is not a new,.,oxie. Records 'indicate òa pos'sihle use of falling weights as early as .1929. 'Dr. Burton McCollum began his experiments in 1938, but it wasn't until 1951 that the method was first proven useful.The first weight dropping crew began commercial operations in Edwards and Sutton .Counties of West Texas in 1953. By 1962, more than '40 weight drop-ping.crews have come into existence with operations in the United States, Canada, Algeria, Iraq, Argent na,òSpanish West Africa, Tunisia, Qatar, Niger Morocco and Libya by most major oil companies and larger independent oil companies. .

Jan 1, 1962

By M. Katzer, R. Klimpel, J. Sewell

The effect of using selective dispersants as wet grinding aids for ores is demonstrated on laboratory scale batch and continuous grinding equipment. A complete characterization of behavior is performed on a given ore to demonstrate correlations involving torque, % solids, net production rate, and slurry weight and volume loading. The relationship between such laboratory data and industrial scale testing results is very consistent.

Jan 1, 1982

In presenting the paper, Mr. Davey quoted subsequent work which yielded k, at miscibility gap composition, of about 50.We can confirm the authors' findings for k j 300 for nearly pure tin to k 2 about 50 (average 47) from our own experience and from repeat experiments on materials described by the authors, at 1150°C.During laboratory-scale trials we also found confirmation of the authors' view that it is more difficult to reach equilibrium from the high-iron (in slag) side than from the low-iron (high-tin) side. Working from the high-iron side tends to yield results that point to a high k, leading to optimistic values of iron/tin ratio in final slags. In practice the smelting of a tin concentrate, unless it is exceptionally low in tin and high in iron, must yield initially a tin-rich slag and therefore equilibrium can only be reached from the "tinny" side.

Jan 1, 1967

By Earl C. Hutchison, Gene Smith

Extensive blasting was required to construct an underground tunnel for a 90 inch sewerage relief line. The tunnel and required excavation extended under an upper middle-class residential area in Atlanta, Georgia for more than a mile and a half and required the use of more than a half million pounds of explosives in the immediate vicinity of houses and residential apartments valued at more than 16 million dollars. Other houses and property valued at more than 80 million dollars were within range to claim blasting damages. An effective blasting damage control program was carried out which limited the number of blasting damage claims to less than 2-1/2% of the total number of potential claims. All but three of the small number of blasting damage claims which were made were effectively denied without any resulting legal actions and less than $3,800 was paid for settlement of the three claims.

Jan 1, 1981

By Hardy J. Smith

The rock mass parameters which need be evaluated to estimate the rippability of rock are briefly outlined and their significance is discussed. Several methods used for estimating rippability are compared, and the advantages of taking into account a wide spectrum of rock mass parameters are emphasized. A systematic means of numerically weighing six rock mass parameters to produce a Rippability Rating (RR) is recommended, and a method of correlating this rating with the refraction seismograph method and with tractor horsepower is shown. Although the overall method demonstrated is systematic and yields specific numerical results, an integrated approach is recommended to its application, taking into account: the Rippability Rating; seismic velocity and geologic material; and other engineering judgment factors.

Jan 1, 1986

By J. D. Miller, M. B. Mooiman

It has been discovered that gold can be extracted from alkaline cyanide solution with primary, secondary, and tertiary amines by adding certain Lewis base modifiers, such as organic phosphorus oxides. Under these circumstances, gold can be extracted at about pH 10, commensurate with the pH of cyanide leach liquors. The selectivity of the amines and amine/modifier combinations for Au(CN)[2] over other metal-cyanide complexes is discussed. Potential applications for the solvent extraction of gold from cyanide solutions are also discussed.

Jan 1, 1985

By Deli Hu, Xiangze Shu, Cai Wang, Hongfu Liu

To detect the place and range of fire is one of the key technologies in the extinction of coal mine underground fire. A fire-prevention and extinction research team of Shanxi Mining College have successfully carried out a program detecting the place of fire with radon. In the past four years the authers have done the detecting work in several mines in Shanxi Province, such as Gujao, Xuangang Louan and Ningwu. The place and scope and the trend of underground fire of coal mine can be now exactly estimated. The data and information from detecting provide a reliable basis for drawing up the scheme to extinguish underground fire and extract mineral coal securely. The principle and method of fire detecting based on radon on surface, the data processing and analysis are discussed in this paper.

Jan 1, 1991

By W. E. Wickerman

The Magnetic Storm Monitor is an instrument that continuously records variations in the earth's total magnetic field at a fixed location. It is intended for use in conjunction with airborne magnetometer surveys. There are stormy periods when changes in the earth's magnetic field are so violent that data obtained with airborne equipment would be of little value. The Monitor provides this information so that flights may be cancelled or terminated, thus eliminating useless flying. Moreover, when some unpredictable change in the earth's field occurs during an airborne survey, the Monitor record, showing a similar event, may serve to salvage the data.

Oct 1, 1955

By M. Niinae, Y. Nakahiro, K. Yamaguchi, T. Wakamatsu

The rare earth magnet has a good performance and the production is increasing year by year. Two types of rare earth magnets are presently made as industrial products. One is a Nd-Fe-B intermetallic compound magnet and the other is a Sm-Co alloy magnet. The mixed scraps of Nd-Fe-B intermetallic compound and Sm-Co alloy are sometimes produced in the step of production. Therefore it is desired that a recycling system of mixed rare earth magnet scraps should be established. In the present study, hydrochloric acid leaching of the oxidizing roasted products of Nd-Fe-B intermetallic compound and Sm-Co alloy and solvent extraction of metals such as Nd, Sm, etc. are tested to obtain the fundamental data for the hydrometallurgical treatment of the mixed rare earth magnet scraps.

Jan 1, 1995

By Christopher Haycocks, J. Richard Lucas

The growth of computer and ground control technology in recent years, combined with an urgent demand for low-cost fossil fuels and mineral resources, has set the stage for full-scale utilization of computers in mine planning. Steeply rising production costs and the need to preserve the environment are placing great demands on engineers to improve their mining efficiencies, which can best be accomplished by applying the full capabilities of the computer. Pressure to develop and perfect programs with an immediate potential for improving mine design, reducing mining costs and extending the viable coal reserves of the country has already come to bear in the form of exploding energy requirements, environmental considerations and the visible limitations of other energy sources.

Jan 4, 1973