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By Don Belsher

Work on contract H0272007 is summarized for the period of 1 February 977 to 1 February 1978. The initial evaluation of two potential systems for the location of well casings, voids, and tunnels in coal are described. The pulse measurement equipment used for the evaluation of the antennas selected possible use with a pulse time domain system and an FM-CW system is described. A TEM horn antenna design potentially suitable for use with these systems is given. An operational comparative analysis between various antenna types is presented.

Jan 1, 1978

By Gary Almeraris, Vincent Jr Tirolo

Traditionally, “Means and Methods” were the sole responsibility of Contractors. However, because of a number of litigious projects in the 1970s, Owners and their Engineers began including Suggested Methods of Construction (SMC) in Contract Drawings. By the late 1990s these SMCs were becoming baseline “Means and Methods” with Contractor recommended changes often considered as Value Engineering proposals. By 2004, the word “Suggested” was sometimes changed to “Prescriptive.” Owners are also purchasing TBMs and other mining equipment for Contractors prior to bid. Is limiting the contracting community’s innovation in developing their own “Means and Methods” and selecting their own equipment in the best interests of the Owner? Does it reduce the Owner’s, Engineer’s or the Contractor’s risk? Are claims reduced and finally what is the impact on the bid? A questionnaire was sent to more than fifty senior engineering field and management personnel representing more than 30 heavy construction companies to ask their opinion on these questions.

Jan 1, 2005

By Y. Sasseville

"Niobec has been using vibrating screens and screw classifiers as a double stage classification in its grinding circuit since the very beginning of its operation in St-Honoré. Most of the other mineral processing plants around the world uses cyclones as the classification device in their grinding circuit. The difference between these two methods are well known in terms of capital cost and grinding efficiency but the differences in terms of the impact on the downstream processing stages are a lot harder to predict and are case specific. In the interest of lowering the capital cost of a future expansion project, Niobec decided to test the cyclones in its actual grinding circuit and evaluate their impact on the recovery of the downstream processing stages as well as the operating cost of the mill. We switched between cyclones and screens for 8 month in 2013 and early 2014 and we are now operating only with cyclones since march 2014.INTRODUCTIONThe Niobec mine and concentrator were built in the mid 70’s and at that time, the mill was processing 1 500 tons per day. Over the years, many expansion projects have brought the plant to 7 000 tons per day. Throughout the initial concentrator design and commissioning, screens have been chosen over cyclones because of their higher classification efficiency which is known to reduce variability and limit the fine generation especially due to a high undersize classification efficiency. Just like many other plants, fine particle generation is a major problem at Niobec because of its negative effect on downstream processing stages. In the interest of lowering the capital cost of a future expansion project, Niobec’s engineering team decided, 35 years later, to test the cyclones in its actual grinding circuit and evaluate their actual impact on the final recovery and the operating cost of the mill.The grinding circuit is separated in two lines which will be called Circuit #1 and Circuit #2 along this paper. Circuit #1 is, as you can see in Figure 1, composed of a rod mill and two parallel ball mills in closed circuit with screens and screw classifiers. The screens oversize are sent to the screw classifiers while the undersize are sent to the next processing stage. The screw classifiers overflow are both sent back to the pump box while their oversize streams return in their corresponding ball mills for further grinding. Circuit #2 is, as you can see in Figure 1, quite the same as Circuit #1 except it has only one set of screw classifier and ball mill. Figure 1 also shows the modification in arrangement each circuits went through to integrate the new cyclones. One of the ball mills in Circuit #1 now appears dotted because it can still be used but is not now"

Jan 1, 2015

By C. Babcock

When a flat-lying mineral deposit such as a coal seam is mined, some coal is left to separate the roof and floor so that miners and machines can safely mine the seam. The mineral left is in the form of mine pillars. If too much is taken, support problems and unsafe working conditions result. If too little is taken, the mining operation will be unable to compete economically with other mines. Therefore, one must select pillars of the optimal size to maximize mining recovery and minimize risk to miners and equipment. Later, if the pillar support is no longer needed and the surface can be allowed to subside the thickness of the coal seam, then the pillar support can be removed to increase mining recovery, and initial pillar size is not as critical. Only a small part of the information available on pillar design can be presented here. The purpose of this report is to summarize some of the work done by the U.S. Bureau of Mines and others on pillar design, which is reported in the literature from 1833 to the present, and present rock mechanics test results that aid in understanding mine pillar behavior. The variable names used are those of the authors cited. This results in multiple use of some variable names.

Jan 1, 1994

Oil sands processing generates huge volumes of slurry, known as tailings, that is being stored in tailings ponds. The volume of produced tailings is a very important factor in oil sands surface mine planning, because the available area for dam construction is limited to the lease areas. On the other hand, oil sands operators cannot leave mine sites without reclaiming the tailings ponds. Since most of the reclamation material is generated in either oil sands mining or processing, it is reasonable to include reclamation material requirement as part of long-term mine planning. In this paper, an integrated optimization framework is proposed to maximize the net present value (NPV) of the produced oil sands, with respect to tailings capacity constraints and reclamation material requirements. A mixed integer linear programming (MILP) model is developed to find the optimal solution for long-term mine planning problem. A sample bitumen processing flow sheet is used to formulate the volume of produced tailings, based on Clark hot water extraction method. To verify the proposed model, it is coded in Matlab and run using CPLEX. Run results for real-case oil sands dataset show that the optimal production schedule meets material requirements for reclamation, tailings volume is within tailings capacity range in all periods and the production schedule follows the predetermined horizontal direction.

Feb 27, 2013

By A. McEachern

At the Annual Meeting of this society, held in Halifax last year, a paper entitled "Closed System Breathing Apparatus" was read by I. C. Mackie, metallurgist, British Empire Steel Corporation. Coming from such an authority it was most instructive and illuminating. The purpose of the paper was to emphasize the necessity of a full supply of oxygen and the danger of oxygen shortage in the use of rescue breathing apparatus. In connection with this he pointed out: "In times of emergency, when life is at stake, rescue men cannot be restrained from using their utmost endeavor, and unless the apparatus is adequate to meet the heaviest load, the result may be fatal to the wearer. The body's demand for its oxygen requirement is absolutely imperative and must be granted at once. We can do without food for many days and without water for many hours, but we cannot do without full requirements of oxygen even for a few minutes. Furthermore, the victim of oxygen shortage gets practically no warning. He may fall helpless or unconscious before realizing that he is in a serious condition." Hence the necessity for expelling all the nitrogen from the breathing-bag and filling it with pure oxygen; also filling the lungs of the wearer with oxygen before he begins to use the breathing apparatus. This practice is general at all the collieries under the British Empire Steel Corporation.

Jan 1, 1924

By James B. Templeton

"IntroductionWith the steady rise of the cost of coal and freight, the time is now ripe for an investigation into the feasibility of using the heat pump for heating purposes in fairly remote industrial areas.The gold mines of northern Ontario seemed to be a most likely place for the application of the heat pump.It was decided that the first step in the investigation would be to determine what economic advantage was to be gained by using the heat pump and thereby determining whether a further and more detailed research programme was warranted.If we can use the heat pump with economic advantage, we can reduce our mining costs and make a worthwhile contribution to our national economy by reducing the import of U. S. coal.The investigation was conducted under the auspices of the Nipissing Fellowship and directed by Professor R. E. Barrett of the Department of Mining Engineering, University of Toronto.With the able guidance of Mr. C. S. Gibson, of the Mines Accident Prevention Association of Ontario, the author visited the following mines: Mcintyre-Porcupine, Delnite, Dome, Lake Shore, Wright-Hargreaves, Kirkland Lake, Macassa, and Kerr Adcliso11.In all cases, the management and technical personnel of these mines were most co-operative and helpful in supplying information and ideas.It should be emphasized at the outset that the design and operation of the heat pump itself is by no means complicated or even new. The reason we hear so much about it today is because there have been improvements in compressors, motors, and heat exchangers in the past few years, and because fuel and freight rates have risen to such a point that, in some cases, the heat pump now has an economic advantage over other methods of heating."

Jan 1, 1950

By K. C. McMahon

This report is the result of the engineering efforts performed by the Mining Equipment Operations of FMC to develop methods of automating a continuous miner. This work was done as part of modification number three of the contract for the development of a miner/bolter system. As the demand for energy places an ever-increasing pressure on the coal mining industry to produce more coal, methods for underground mining which will increase productivity with a con-current increase in safety are being actively sought. Removing the machine operator from his station on the continuous miner and placing him at a safer location behind the machine while retaining his control functions via an umbilical cable or a radio link was an important first step. However, the problems of poor visibility, no control "feel", and the judgmental problems of controlling the sump distance and the shear limits have not been conducive to the productivity increase that is desired.

Jan 1, 1975

By V Rodríguez, M Hormaza, R J. Romañach, C Pinzón-de la Rosa

The authors have presented their ideas for developing a powder sampling device in the I-Corps™ program sponsored by the National Science Foundation (NSF). This is an intensive customer discovery program developed to increase the economic impact of the research sponsored by NSF.The I-Corps™ program requires performing at least 100 interviews with potential customers in various industries. These interviews are essential to establish the need for a particular product or solution, and identify potential commercialisation partners and competition. The interviews have revealed the absence of Theory of Sampling (TOS) principles in many companies. The interviews are designed to identify the difficulties associated with current sampling practices that do not meet TOS principles.The I-Corps™ program is a significant challenge for scientists who often avoid discussing a concept in fear of losing their research idea. The program teaches how to obtain information without releasing the important intellectual property related to a product development idea. The I-Corps™ methods have been used to discover the prevailing ideas on sampling in various industries.I-Corps™ also teaches how to present ideas to investors; another significant challenge for a scientist. We are currently learning to present sampling and TOS to investors and business development experts, and will share some of these experiences.CITATION:Pinzón-de la Rosa, C, Rodríguez, V, Hormaza, M and Romañach, R J, 2017. Theory of Sampling meets the National Science Foundation I-Corps™ program, in Proceedings Eighth World Conference on Sampling and Blending , pp 351–354 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By Joseph G. Carleton

INTRODUCTION The increasing concern for the environment may well present far more opportunities than problems for those involved in all phases of tunneling. All too frequently in the past, environmentalists and their concerns have been cast in a negative light, as obstacles to be overcome. Often forgotten is the fact that these same environmental concerns have created a rapidly increasing demand for new tunnels. Tunnels for rapid transit projects, clean water supply, and sewage treatment have been given a boost because of environmentalists' concerns about overuse of automobiles, inadequate water supplies, and improper sewage disposal. Concurrent with increasing use of tunnels to help solve or alleviate some of our environmental problems is an obligation not to create new ones in the process. Concerns which we feel responsible tunnel owners, engineers, and contractors should address themselves to include: (1) Minimum energy consumption, both during construction and in operation of the completed project; (2) proper storage and/or disposal of the excavated material; (3) minimum disruption during the construction process - noise, traffic, unnecessarily unsightly work areas, and possible weakening of foundations of nearby structures; and (4) a finished project consistent with community and environmental goals. We are especially concerned about two things. First, the longrun implications of a project -- what's good for a few people in the short-run may be bad for most of the people in the long-run. Cutting corners to save a little money now is false economy. Second, the fact that ultimately we all share the same earth -- its water, air,

Jan 1, 1974

The Australian mining industry is at an interesting stage in its development. Of the large number of mining companies in Australia, some are still solely domestic in their focus, others have made their first tentative forays offshore, and others are global players of significance in tile world industry.   It is not long ago that the entire industry was almost exclusively domestic in its focus. Very few companies before the early 1980s had ventured offshore, and those that did so were considered quite risque. The initial moves were made mainly by large companies who could afford to lose the funds expended in getting started in a range of offshore locations.   Almost all offshore jurisdictions were considered to be high risk compared to the safety of home - I recall the extreme difficulty I encountered in the mid 1980s in endeavouring to persuade a Board to joint venture into an attractive gold opportunity in South East Asia.   One of the problems inhibiting the offshore development of the Australian mining industry was that some mining companies had had unfortunate experiences offshore. Others had heard of those who had had unfortunate experiences offshore and, as such, 'offshore' gained a bad name and the more risk averse boards and. management of the time simply put the whole idea into the 'too hard' basket.

Jan 1, 1995

By Walter Renton Ingalls

IN SEVERAL papers and addresses during the past two years, I have dwelled upon some of the economic consequences of the war. The fundamental thought that I have sought to convey is that the world became immensely poorer by the war, not only in material wealth and population, but also in the psychology and morale of the people. I do not see how there can be any intelligent dissent from that statement. All the ideas of post-war prosperity were manifestly fallacious, manifestly fallacious from the outset. If there had been any truth in them it would have followed logically that a great war, with all its destruction of wealth, health and life would be a good thing. Therefore, let us have a great war every ten years or so. Such an idea would be both monstrous and absurd. Assuming then the acceptance of my premise, I have tried to show that the losses by the war could be made good in a short time, i.e., in a relatively short time, only by doing things a great deal better than formerly, and that the accomplishment of such a result called for greater transparency in industry, for industrial cooperation, for thinking in terms of industries as a whole, and for the greater exercise of engineering functions. All of this introduced, of course, the position and psychology of labor. I say frankly that I do not look for labor to contribute any constructive thought to the upbuilding. I neither expect it nor hope for it. This is a pity, for it could do so much for its own economic advancement if it would. However, it never has done so, but rather has benefited only from the exercise of the talents of the few, and the main hope now is to bring it into a passive state, dispelling the resistive fallacies that developed during the war. Let us briefly examine the nature of these.

Jan 1, 1921

By F F. Pitard

Observation from attending many conferences around the world reveals that many people are constantly shifting from the word ‘error’ to the word ‘uncertainty’ without a clear vision of what the subtle difference is. The same applies to a large swath of the scientific literature, in which these two concepts are unfortunately often used synonymously, which is a scientific flaw of the first order. In practice, as demonstrated in the Theory of Sampling (TOS), there are both sampling errors and sampling uncertainties. Sampling errors can easily be preventively minimised, while sampling uncertainty for a preselected sampling protocol is inevitable. P M Gy’s work, supported by G Matheron’s critical reviews, demonstrates beyond any possible doubt that sampling uncertainty cannot be achieved if sampling errors are not preventively minimised by applying very stringent rules that are too often ignored by sampling practitioners. A clarification, in line with the TOS, is presented to mitigate the confusion created by circles favouring the use of uncertainty versus the use of the word error. Both words are very different in nature and scope and they are both necessary in their due place and time.CITATION:Pitard, F F, 2017. From errors to uncertainty – a clarification for proper use by the Theory of Sampling, in Proceedings Eighth World Conference on Sampling and Blending , pp 355–358 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By Mustapha A. Raji, Alafara A. Baba, Christianah O. Adeyemi, Aishat Y. Abdulkareem, Rafiu B. Bale, Malay K. Ghosh

The increasing demand for pure aluminum and aluminum compounds of industrial quality from kaolinite ore cannot be overemphasized. Nigeria is one of the African countries endowed with abundant solid mineral resources that have not been sufficiently exploited to assist its indigenous industries. A wide array of applications of pure aluminum and its compounds are available, such as paper filling, refractories, adsorbent, catalysis, and paint additives. In this study, the upgrading of a Nigerian biotite-rich kaolinite ore by a hydrometallurgical route was investigated in oxalic acid media. During leaching studies, the effects of parameters including reaction temperature, lixiviant concentration and particle size on the extent of ore dissolution were examined. At optimal conditions (1.0 mol/L C2H2O4, 75 °C), 92.0% of the initial 10 g/L ore was reacted within 120 min. The dissolution curves from the shrinking core model were analyzed and found to conform to the assumption of surface diffusion reaction, and the calculated activation energy of 33.2 kJ/mol supported the proposed model. The unreacted product (~8.0%) analyzed by XRD was found to contain siliceous impurities and could serve as a valuable by-product for certain industries.

By Grant R. Brown

The objective of this paper is to describe a study sponsored by the U.S. Department of Energy during which a model was developed to optimize haulback mining procedures in single and multiple seam contour mines, The study objective was to achieve financial- based productivity increases approaching twenty percent. This paper reviews the results of the first year's Phase I activities, which include four main tasks: formulate a methodology that can be used to select equipment and mining procedures that result in optimal performance in a particular haulback mining situation; conduct field studies of representative single and multiple seam mines to obtain quantitative background information for development of the formulated methodology: develop the methodology into a useful design tool for mine operators; and prepare plans for field tests to evaluate the effectiveness of the developed tool.

Jan 1, 1981

By K. Papke

Nine western states contain significant barite deposits, but most deposits are in Nevada, which has been the principal western producer for more than three decades. Nevada produces about 85% of the total United States production, but about one-half of the barite consumed in the country is imported. Approximately 95% of the barite is used in drilling muds. Sharply decreased oil and gas drilling, starting in early 1982, severely depressed the domestic barite industry. Other problems for western barite include long distances to the areas of major drilling, high railroad-freight rates, and increased barite imports. Bedded deposits, formed by submarine exhalative processes, account for almost all western production, and reserves are large.

Jan 1, 1983

By Craig Haase

A. Introduction

Jan 1, 2003

By Mustapha A. Raji, Alafara A. Baba, Christianah O. Adeyemi, Aishat Y. Abdulkareem, Rafiu B. Bale, Malay K. Ghosh

The increasing demand for pure aluminum and aluminum compounds of industrial quality from kaolinite ore cannot be overemphasized. Nigeria is one of the African countries endowed with abundant solid mineral resources that have not been sufficiently exploited to assist its indigenous industries. A wide array of applications of pure aluminum and its compounds are available, such as paper filling, refractories, adsorbent, catalysis, and paint additives. In this study, the upgrading of a Nigerian biotite-rich kaolinite ore by a hydrometallurgical route was investigated in oxalic acid media. During leaching studies, the effects of parameters including reaction temperature, lixiviant concentration and particle size on the extent of ore dissolution were examined. At optimal conditions (1.0 mol/L C2H2O4, 75 °C), 92.0% of the initial 10 g/L ore was reacted within 120 min. The dissolution curves from the shrinking core model were analyzed and found to conform to the assumption of surface diffusion reaction, and the calculated activation energy of 33.2 kJ/mol supported the proposed model. The unreacted product (~8.0%) analyzed by XRD was found to contain siliceous impurities and could serve as a valuable by-product for certain industries.

By R. H. King

Suboleski and King (1990) analyzed the reasons for the dramatic increase in underground coal mine productivity during the last 10 years. This paper examines whether this increase can be extended. The paper forecasts whether the mix of technological, procedural and other factors that produced the increase will change in the future. The forecast is based on the base case and spreadsheet production model described in the previous paper.

Jan 1, 1991

By J P. Burr

The Waterview Connection will complete a strategic Auckland motorway route linking the south, west and north. The project will include 2.1 km of ‘undrained’ driven tunnels, 500 m of drained cut-and-cover tunnel and tunnel portals.The project is aligned beneath a stream valley of Oakley Creek, which is incised through alluvium and in places overlain by landfill, between Mt Albert volcano and a ridge formed in alternating sandstones and siltstones. The resulting topography, geology and hydrogeology of the tunnel alignment are complex.The Assessment of Effects required estimation of the likely settlements resulting from the tunnel construction and assessment of their effects on the buildings, services and other features. A conservative approach was taken when estimating settlements in order to provide an upper bound estimate of the consequent effects. There are three sources of these settlements: mechanical settlement from the tunnel excavation, mechanical settlement from the displacement of retaining walls and consolidation settlement from the groundwater drawdowns during construction and, in some cases, in the long-term.The settlements from these sources were calculated independently and then combined to identify the most critical effects. These combined settlements were used to assess the potential damage to the buildings, services and other features above and around the tunnels. The combined settlement results generally followed the anticipated trough shape centred on the underlying tunnel but with some noticeable effects relating to the underlying geology and hydrogeology.The effects on buildings were typically assessed as negligible with some areas of very slight to moderate damage predicted. Effects on services are anticipated to be minor but some large and older pipes will require specific monitoring during construction. A monitoring programme is proposed to allow the actual settlement and effects to be compared to those estimated with appropriate responses should those effects significantly differ.This paper describes the methods used to calculate and combine the settlements and assess their effects.

Mar 8, 2011