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By William G. Pariseau

The purpose of this paper is to present a design procedure for the quantitative estimation of support load requirements in underground mines. Emphasis is upon the basic features of support behavior common to a large variety of support systems-bolts, timber sets, stope fill, steel arches, concrete liners and so forth. A strong reliance is placed upon fundamental principles and modern computing techniques for their quantitative implementation. Example problems illustrate the approach. Where artificial support is required, the ground in the vicinity of the face usually stands unsupported long enough for the support to be installed. At the time of installation, the load transferred to the support from the adjacent rock is essentially zero, although in some cases there may be an initial set load, for example, from timber blocking. With the passage of time and advance of the face, ground motion loads the supports. If the support system is properly designed, then the additional loading poses no threat to the safety and productivity of operations. If not, then difficulties may arise including high maintenance costs, hazardous work conditions and reduced productivity. Of course, over-design can be equally wasteful. Quantitative estimation of support loads is therefore essential to overall efficiency in mining.

Jan 1, 1975

By S. A., Taylor

IT is very difficult to arrive at exact figures for the cost of maintaining excess capacity of coal mines, but we can approximate the various items. To do this, I will take the Pittsburgh district of Pennsylvania and the other districts can be compared to this one. I believe we can take the depreciation item of plant ac- count as a whole and discount it over a period of 20 years; while this is high for some items it is low for others and I believe it is not far from a safe basis. This equals 5 per cent per year, and this depreciation will take place about as rapidly when not in use as when in operation. A fair value in the Pittsburgh district to- day for plant and houses is close to $4 per ton per annum. At 5 per cent this will equal 20 cents per ton per year. The item of keeping the mine in condition, free from water, etc., will be close to an average of 2y2 cents per ton per annum.

Jan 1, 1928

By FREDERICK C. BROWN

THE practice of fine-grinding is now being so successfully - carried on in some fields, notably in West Australia, and its advisability has been so frequently pointed out' that the matter in this paper is not put forward as being new ; its chief object being to call attention to the importance of fine-grinding in the treatment of comparatively low-grade ores. I have been engaged during the last five years in the cyanide-treatment of ores in the Ohinemuri district (North Island), New Zealand, and I consider that, in the near future, extremely fine-grinding (almost sliming) will become a very important feature of the milling-methods in this field, since it seems absolutely necessary to reduce the most of ores to a very fine state of division if a high extraction is to be obtained; and, in most cases, the extra percentage of saving will leave a good margin above the increased cost of treatment due both to the fine-grinding and to the interest on the capital spent for the grinding-machinery. The average ore of the Ohinemuri field is composed of a quartz-gangue with some calcite, carrying the gold-value in the form of an alloy of gold and silver in about equal proportions, and the silver-value in the form of mixed sulphides of silver, usually associated with a considerable amount of iron pyrites. In the upper levels, the ores are decomposed and carry large quantities of black manganese oxide and some iron oxide, but, as. depth is reached, the decomposed ore gives place to sulphides and, in some mines, rhodonite, manganese silicate, is present in fairly large quantities. The average value of the

Jan 1, 1906

By Éder Domingos Oliveira, Leandro Viana Teixeira, Carlos Antonio Morais, Ruberlan Gomes Silva

The purity of rare earth products depends on the ability of the reagents used to selectively promote the precipitation of the rare earth elements (REE) from impurities present in sulfuric liquors. The present study aims at investigating the conditions required to precipitate REE, either as rare earth oxalates or carbonates, from purified rare earth sulfuric liquor with a low Al3+ and UO2 2+ and a very high Ca2+, Mg2+, Mn2+, and SO4 2− impurity content. The rare earth sulfuric liquor was obtained in a previous study by the reaction of a rare earth ore with sulfuric acid, pyrolysis at 700 °C/2 h, cooling at 20 °C, and water leaching. The impurities such as Fe3+, Th4+, and PO4 3− were completely removed from the liquor in two consecutive neutralization steps. In order to recover the REE, the purified rare earth liquor was then treated with oxalic acid and sodium carbonate. Rare earth oxides (REO) precipitated with oxalic acid displayed a very high purity (99.2% w/w) and low impurity content. In contrast, the rare earth carbonates precipitated with sodium carbonate presented a comparatively lower REO content (68.5% w/w) and 94.2% of purity, but with a higher content of impurities. Better precipitating conditions were achieved at 60 °C, compared with 20 °C, and under stoichiometric reagent consumption, with REE precipitation efficiencies higher than 96%. The dosage above the stoichiometric condition caused the precipitation of calcium oxalates and co-precipitation of rare earth sulfates when oxalic acid is used, and precipitation of calcium, manganese, and uranium carbonates and also a co-precipitation of rare earth sulfate when sodium carbonate were used. An integrated flowsheet to produce a high-quality rare earth product from rare earth sulfuric liquor containing some impurities is proposed.

By Rclssell Gibson, F. S. Turneaure

The tin deposit of Monserrat; Bolivia, consists of one major vein 1600 m in length. The ore is unusual because of the notable quantity of teallite, even though cassiterite is the principal tin mineral. The deposit, formed at shallow depth under a wide range in temperature, may be classed as xenothermal. Polished sections reveal a complex history of replacement, with low-temperature minerals deposited before high-temperature minerals.

Jan 1, 1950

By Lorenzo Reyes-Bozo, Ronaldo Herrera-Urbina, Pablo Higueras, Alex Godoy-Faúndez

"The copper mining industry in Chile and perhaps in other countries as well is faced with the challenge to implement the best practices in order to achieve a sustainable and more environment-friendly growth. Relationships between mining industry and society have been historically complex due to its environmental impacts. Whereas the ore grade has declined continuously, this has involved an intensive energy and water consumption thus increasing operational costs at different stages of the concentration process. In the case of copper sulphide ore concentration, froth flotation is the main technology used worldwide. The amount of the different chemical reagents used in flotation plants (i.e., collectors, depressants, frothers and modifiers) affects significantly production costs and has a negative effect on the environment as well. The objective of this research work was to evaluate the use of biosolids and their main components (i.e., glucose, proteins and humic substances) as more environment-friendly flotation collectors for chalcopyrite and molybdenite. For this purpose, microflotation tests were conducted in a modified Hallimond tube. In addition, FTIR and zeta potential experiments were performed to investigate the interaction of biosolids with these sulphide minerals. Biosolids and their main components may interact through physical and chemical ways due to different affinities with such sulphide minerals as chalcopyrite, pyrite and molybdenite, which are present in copper sulphide ores. In alkaline pHs, biosolids and their main components make the zeta potential of the sulphide minerals investigated more negative. These results may provide important information concerning the behavior of the main sulphide minerals in the concentration of copper sulphide ores at industrial scale, wherein mill processes could affect their surfaces properties. Therefore, biosolids and their main components may open an opportunity to be used in copper sulphide flotation plants to partially replace conventional reagents, which are more hazardous and less environment-friendly."

Jan 1, 2014

By Stephen J. Harven

Geologic conditions in eight northern operating sections of Jane Mine, Keystone Coal Mining Complex. Armstrong County, Pennsylvania are defined by utilizing drillhole data and underground geologic mapping. Three of the eight sections are experiencing difficult mining conditions in the Shelocta "0" coal seam (formerly the Lower Freeport). The five remaining productive sections will exhaust their reserves within one year. Coordinating mine planning with future production levels is aided by indicating areas that appear favorable and lack the geologic conditions that cause difficult mining. Roof rock 1 ithologies, lithologic variations in and below the floor, jointing, overburden thickness, coal splits, paleochannels. and clay veins are the principal geologic factors believed to influence mining conditions in Jane Mine. Careful definition of each cause allows for a reasonable assessment of future mining conditions.

Jan 1, 1987

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are in most cases developed and tested in close cooperation with demanding end users before Being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the Drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, Atlas Copco has placed emphasis on hole straightness and the need for hole logging and positioning. By applying state of the art Technology to today?s computerized drilling rigs, major steps in improving overall drilling and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the Rotary drilling product line.

Jan 1, 2010

By George W. Maynard

(Pittsburg Meeting, March, 1910.) AT the Pittsburg meeting of the Institute, May, 1879, I made the first announcement in America of the results obtained by Sidney Gilchrist Thomas and Percy C. Gilchrist, ill their efforts to eliminate phosphorus in the manufacture of steel in the Bessemer converter and the open-hearth furnace.1 The first published statement in an American newspaper was a reprint of the first Thomas-Gilchrist paper, 2 which I sent to J. C. Bayles, at that time the editor. At the suggestion of many friends who were present at the Pittsburg meeting, and others who are cognizant of the beginnings of the process in the United States, and for the information of the younger generation of the iron and steel fraternity, I have thought it eminently proper that the history of the process in detail should be given where I made the first announcement and where the process has had its largest development. During my residence in England, from April, 1873, to February, 1879, and as a member of the Iron and Steel Institute since 1874, I was present at many of its meetings during those years. At nearly -every meeting the burden of discussion was the question of the use of pig-iron containing phosphorus in the. manufacture of steel by the Bessemer or the open-hearth process. In my biographical notice of Thomas;3 read at the New York meeting of, the Institute, February, 1885, I show that the working-out of the process was not a hap-hazard or accidental inspiration, but the culmination of many years of investigation of experiments and theories which had been carried on and advanced by chemists and metallurgists at home and abroad. 1 Trans., viii., .5 (1879-80). 2 The Iron Age, vol. 22, No. 17, p. 3 (Oct. 24, 1878). 3 Trans.. xiii., 785 to 791.

Jul 1, 1910

By Jason Berenyi

Presentation Overview ? What is Potash? ? Where are the potash deposits? ? Current potash mines ? production, capacity and planned upgrades ? Saskatchewan Saskatchewan?s Potash Production Potential s ? Current Status of Potash Exploration ? Increasing Demand for Potash ? Saskatchewan global role

May 1, 2009

These proceedings consist of papers presented at two Bureau of Mines Technology Transfer Seminars in early 1980 for the purpose of disseminating recent advances in mining technology related to surface coal mining reclamation.

Jan 1, 1980

By S. Anderson

Advances in inexpensive computer automation led to the development and utilization of a computerized ore control system at Cyprus Coppers tone Gold Mine near Parker, Arizona. These new ore control practices improved accuracy, performance, and productivity of the ore control effort. An automated system for data collection, including bar coding of blast hole samples, laboratory analysis, data management, grade estimation, cut delineation, and ore zone stakeout, plays a major role in ore control practices. This is of particular interest because of the large amount of blast hole information being processed, analyzed, and reported daily.

Jan 1, 1991

By W. E. Lytle

Environmental permitting is a critical component for joint-venture projects located in the Commonwealth of Independent States (CIS). This paper presents the basic CIS regulatory environmental requirements for permitting of a hypothetical mining source and emphasizes air permitting. Topics which will be covered include: the Expertiza process, air pollution quantification, data requirements, and air pollution modeling protocol. A comparison will be made between permitting requirements for air pollution sources in the United States and a CIS country, Kazakstan.

Jan 1, 1998

By L Blackwell

Strategic mine scheduling is an industry best practice for increasing the long-term value of mining operations and supply chains. The application of optimisation technology such as mixed integer linear programming (MILP) is able to achieve a mathematically optimal result for a given scheduling model. Such a model will typically define the available source material, processing options and desired constraints for accessing and processing the material. Most strategic scheduling models, however, do not include a sufficiently detailed model of capital expenditure options related to capacity expansion.Typical strategic schedule models do not include important capital expenditure features such as capacity decay or expiration (limited lifespan of trucks), precedence relationships over time (rail construction before a new plant or non-linear expansions due to economies of scale) or mutually exclusive option sets (choices of plant size). By not including these features, a strategic mine scheduling model for a capital-sensitive operation is unable to be optimised to deliver maximum value or profitability.This paper presents several results of MILP optimisation using advanced capital expenditure modelling for mining operations and supply chains. Results of the study demonstrate that optimising capital expenditure at the same time as optimising the mining schedule allows for minimisation of capital purchasing, optimal timing for those purchases and optimal scheduling around them. Overall, this results in an increase in net present value.CITATION:Blackwell, L, 2014. Capital expenditure modelling for strategic mine scheduling, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 315–322 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By A. K. Debnath

The water resource is key to survival of the mankind and this resource is now becoming critical in many parts of globe including India. As per an assessment of Central Ground Water Board (CGWB) of India, a huge shortfall of about 58 billion m3 of water is anticipated by the year 2050. In order to counter this shortfall, there is thrust from Government of India to adopt water conservation measures. National Environment Policy, 2006 of Government of India also stresses upon the need to take up water conservation measures for water security of the country. The coal mines in India provide an excellent opportunity to take up water conservations measures therein. The mine water is not acidic unlike western countries and it conforms to the prescribed regulatory standards. This nature?s gift is utilized in Coal India Limited by allowing mine voids to get filled with mine water. The net recharge potential of the opencast mining area is found to be about 5% in comparison to 2% in non-mining area offering good prospects for ground water recharge. The seasonal rainwater is also diverted into mine voids left at the end of mining operations which act as huge reservoirs/ pit lakes for storage of the water. They also serve as surface water bodies for recharging of water table in the surrounding areas. The area and space left from where coal has been extracted completely in underground mines and will not be entered by any man or machinery after the extraction, called goaf, are also potential source of water conservation. These additional water resources created are being utilized for meeting the industrial, domestic, irrigation and other requirements of the projects and local communities eliminating the need to tap other fresh water resources including ground water. Presently, 75% of the water demand of the coal mining project is being met from the water stored in the mine pits. In future, CIL is likely to create about 3.3 billion m3 of water resource, on an average, in its opencast mines alone. In the mine closure plan of opencast mines, the last cut is proposed to be developed into water body for recharge of ground water and creating additional water resources. A clean potential source of potable water is thus developed after mine closure. This will ensure water security of the country.

Aug 1, 2013

By Jochen Petersen

This paper gives an overview of the various strands of postgraduate and undergraduate training offered in the Department of Chemical Engineering at UCT. Since 2003 the Department is offering a formal postgraduate MSc programme in hydrometallurgical engineering aimed especially at graduate work-based engineers, with 5 weeks of intensive course work plus a research dissertation on a work-related project. This programme has now run 5 times over the years and produced some 20 degrees. The paper reflects on the experiences with running the course, especially the difficulties experienced with supervising industry-based external students. Furthermore, through the Department a graduate training program is offered for all junior metallurgists at a major South African minerals company. This 2-year program, which is currently on its 12th cohort, offers 1 or 2 week intensive blocks of course work alternating with longer stints where the candidates are based at various operations. Although primarily focussed on minerals processing, it has a significant element of hydrometallurgy in it and in recent years an advanced hydrometallurgy stream has been introduced. The paper reflects on the development of the program over the years, the benefits it has provided to the company as well as some of the challenges that remain. Finally the paper gives an overview of hydrometallurgy related undergraduate and research-only postgraduate MSc and PhD projects at the university. Some emphasis is placed on the recently launched South African Minerals and Metals Research Initiative (SAMMRI), a joint government-industry programme to support university-based research in the area of applied metallurgy.

Jan 1, 2014

By Douglas Rudenko

Have you ever had a neighbor complain about a blast one day, but says the next day’s blast was better, even though the Peak Particle Velocity (PPV) increased? How about neighbors that complain about a small trimming shot, but don’t complain about a big production shot? Have you ever reduced the pounds/delay and gotten more complaints ? Mine operators are often bewildered when trying to correlate blast design parameters to homeowner complaints. When complaints come, standard practice is to set up a seismograph in the neighbor’s yard to monitor the blast. Immediately after the blast, the neighbor usually reappears from the house wanting to know the seismograph reading. When told that the PPV was 0.1 in/set, well below damage levels, the homeowner explodes saying “Your machine is wrong”. Perhaps he is right. Understanding why people complain about blasting is not about PPV, it’s all about structural response. People could care less about how much the ground vibrates; they only care about how much their house vibrates. In this paper we will examine the primary factors that control structural response. Through the use of a large array of digital seismographs, the effects of two production blasts on a community surrounding a quarry are studied. The predicted structural response resulting from each blast is calculated at 175 seismograph locations. The predicted response is then correlated to previous research on human perceptibility to vibrations. The results of this analysis and correlation give a better understanding of what the residents actually feel in their homes. The detonations of two single-hole signature blasts are also recorded by the array of seismographs revealing the dynamic characteristics of the geology ‘surrounding the quarry. Once the influence of the geology was understood, blasts were configured to disrupt the natural rhythm of the site through the use of millisecond delays.

Jan 1, 2000

By William Catron, Cyril U. Colledge

BECAUSE the rich La Colorada orebody of the Cananea Consolidated Copper Co. does not outcrop at surface, after its discovery (by churn drill) and before mining was begun, a large amount of development work was done to learn the shape and extent of the ore and to provide for economic and effective mining. As these openings progressed, the actual shape of the orebody became known and with this knowledge came the realization that mining this rich and unusual deposit without loss of ore or danger to workmen presented several difficult problems. This paper will describe one of these problems; namely, the handling of an inverted cone-shaped core of barren rock, on the periphery of and below which the ore occurred. It was clear that as the ore was mined out from around and under this inverted cone of rock, weighing about 3,000,000 tons, it would hang over the workings, held suspended only by its own tensile strength and threatening to crash into the stopes below with disastrous results to men and mine. The method of mining developed during the years 1928, 1929 and 1930 anticipated and provided for the eventual collapse of this core of rock. In November 1936 the core settled down gradually on the edges of the stopes descending a total of about 50 ft. vertically. The men in the stopes had ample warning and no lives were endangered. There were no air blasts in the mine. The core broke loose from its top support at the 500-ft. level along old fracture planes and evidently is crushed to the ninth level. Movement was of short duration; the following shift went to work in the stopes as usual. No ore was lost. GEOLOGICAL STRUCTURE The shape of the orebody is illustrated in Fig. 1. The geology of the Colorada orebody has been described by V. D. Perry1 and by W. G.

Jan 1, 1938

By Allan A. Este, Bruce Arthur

"Rio Algom's Stanleigh Mine and Mill Operation Was' officially started up in August 1983. In September 1982, Rio Algom contracted Estonix International Inc. from Lively, Ontario, to develop and implement two innovative programs: (1) Work Renovation Planning, and (2) Systems Performance Training. This paper deals with the development and implementation of these two concepts relative to the plants technology from start-up to present and the exceptional results achieved. This paper discusses how a small but motivated workforce resulted in the smooth transition from startup to full production. It also deals with how these concepts were applied elsewhere in the organization which permitted a successful transition and downsizing of the over-all operation.IntroductionRio Algom Limited produces uranium in Elliot Lake, Ontario. In the late 1970s Rio Algom entered a contract with Ontario Hydro to supply uranium from its Stanleigh property, which had been idle since 1960. The mine was subsequently upgraded, and a new modem mill was designed and built, commencing operation in 1983.From then until September 1990,Rio Algom had three producing mines and mills in the Elliot Lake area. Quirke mill, with a capacity of 6350 tonnes per day, operated continuously from 1968. The Panel mill with a 3000 tonnes per day capacity, operated since 1979. Stanleigh mill continues to operate under long-term contracts, although at a production rate about 25070 lower than its rated capacity of 5000 tonnes per day.Both the Quirke and Panel mills, although not entirely similar, were conventional uranium mills utilizing crushing, grinding, leaching and ion exchange. As such, and in keeping with the traditional management style, there was a rather large mill operating workforce, which utilized a line-of-progression job classification system."

Jan 1, 1993

The current boom conditions in the Gold Mining Industry, open cut low grade gold mines have become the initial cash flow source for most companies. To achieve the required cash flow the head grade needs to be maintained at the required level. The methods of grade control to achieve .the planned head grade have evolved various systems, one of which is the Ditch Witch Trencher. The application of this machine has revolutionised open cut grade control and Geology and this paper records the various methodologies developed in the Eastern Goldfields of Western Australia.

Jan 1, 1987