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By Thomas C. Shapiro

This is the final article in a three-part series on microcomputers and application software in the mineral industry. The first article covered microcomputer terms and concepts. The second discussed exploration and mining software. This article will examine plant, administrative, and geotechnical software. Every effort has been made to be current in the latest software developments. Rapid change, however, is a fact of life in the computer world and any omission is inadvertent. Introduction Geotechnical disciplines have received considerable attention in software programming. Calculations are repetitive and the formulas needed to solve them are not extremely complicated. These programs are ideally suited to the microcomputer and the microcomputer is ideally suited to the consulting geologist or engineer, due to its low cost and reliability. In fact, the advent of the Apple (a registered trademark of Apple Computer Inc.) and, more recently, the IBM personal computer has caused an explosion of inexpensive software programs available to the microcomputing public. Another area that has benefited from computerization, although not in the same way, has been mineral beneficiation. Here, process control for start-up or phase-down operations has been used in newer plants for some time. Programs to perform various calculations are becoming more common as micros increase in number. Tappi Journal has a section with solutions to handheld-calculator and microcomputer problems. Process Modeling Most process modeling is still done only on mainframes. One such program is called ASPEN PLUS (a registered trademark of Aspen Technology), and a one-week course is recommended so the user can best use the program. This program is available through timesharing from University Computing Co. Programs to find an optimal solution using Linear Programming (LP) have been around for some time. Also, plant process simulation has been possible using simulation programs. Both simulation and LP are expensive to program and run. Although there are LP programs available for some micros, the user must be fairly knowledgeable about how to set up the problem. This is because each problem must be set up as a unique program that typically requires custom programming. There are some programs that can handle blending of mine crudes and examine economic parameters over the life of the mine. Plant Applications Areas relating to mine and plant applications with programs available for micros are maintenance, production reporting, inventory, accounting, and personnel scheduling. Maintenance Maintenance typically requires that certain jobs be performed in a particular sequence and parts be ordered with enough lead time for maintenance to take place on time. There is, therefore, a critical sequence of tasks that must be performed or the scheduled maintenance will not take place. Two answers needed for maintenance project scheduling are: what is the lead time needed

Jan 4, 1984

By Don A. Toth

Until recently, the fire protection systems used to protect mining equipment were based on generically designed, off the- shelf concepts. These systems were reliant on single agent approaches and were generally comprised of a series of small twenty or thirty pound chemical canisters that would discharge their contents when triggered by thermal detection means. As the equipment grew in capacity, the logic used to increase the protection was to add more chemical canisters to the system. Hydraulic excavators and large-scale mining trucks grew dramatically in size into the 1990?s and beyond; with this growth came the increase in major losses due to fire. This was evidenced throughout this period, and continues to be of great concern today. During this presentation you will learn of the significant changes that have come about as a result of this history. Today, dual-agent products, infrared detection and unit-specific, engineered systems are the primary phrases used when discussing how to best protect this equipment from fire loss. This session is a must for anybody looking to optimally protect their equipment assets and for those looking to renew and/or secure new insurance for high value equipment in the future.

Apr 1, 2005

By G. Thom, A. Kay, J. B. Hyde

"This paper will initially outline the specific types of copper castings used in blast furnace iron production. Tuyeres, tuyere coolers and stack cooling plates will be discussed in some depth, with particular reference to their dimensional configuration and purpose.Following this, the failure of such cooling members will be discussed, with special focus on tuyeres. Tuyeres are the most common casting which often requires replacement. Reasons for failure and its effect on operations will also be included.The latter sections of the paper will deal with the strict specifications demanded by ironmakers regarding copper castings. The justification for such rigid demands will be explained through the material presented earlier in the paper.IntroductionThe modern 5000-tpd blast furnace, worth millions, is a large capital investment to be sitting idle. Consequently, ironmakers strive to minimize the loss in iron production and revenue from furnace downtime. Two major causes of downtime are furnace relines and shutdowns to replace damaged tuyeresor tuyere coolers. Copper ancillaries are important items in the production of iron. They are consumable items, therefore they contribute to the campaign life or to the downtime in blast furnace production.Several combinations of lining and cooling systems have been used with varying degrees of success. Blast furnace refractories have evolved from ceramic to carbonaceous linings. The Russians and Japanese have successfully introduced stave-cooled furnaces that may have several forms, such as evaporative cooling. Stelco has two furnaces which use the Russian-designed cast iron system. However, this paper will be confined to the use of copper cast cooling members in a conventional internally cooled furnace.Figure 1 is a schematic cross section of the E blast furnace. The three major sections of a blast furnace-the stack, bosh and hearth-are identified. Further, the locations of the various copper members are indicated. This furnace produces an average of 5300 tons of hot metal per day."

Jan 1, 1982

By Craig M. Sams

"Variable speed mill popularity has grown during the last 10 years with almost every SAG mill fitted with a variable speed drive. In addition, many of today’s larger ball mills are running a variable speed drive for various reasons. In the past, motor suppliers, especially gearless drive suppliers, have considered mills as being an overpriced rotor. This has lead to mills demanding more torque than what a motor can generate. This paper identifies the reasoning of what has happened and how to mitigate the mismatch in the future. Technical and economical issues are discussed, allowing mill operators to make an informed decision of which path to take in deciding what motor to put on a mill.INTRODUCTIONIt has been generally accepted in the past that motor suppliers and specialists in engineering companies understand the workings of a SAG mill or a ball mill and although there is a fair knowledge within the industry, in regards to mill torque requirements, the advent of variable speed drives in ball mills has shown the writer that a complete understanding of the mill torque requirements are not fully understood.This paper will discuss two aspects of mill torque requirements, (operating torque at various charge levels and start up torque), and how it relates to specifying the proper motor torque requirements.MILL OPERATING TORQUEMill operating torque at a given charge level and density in a mill is essentially constant throughout the entire speed range. For the purpose of this paper, we will take a 38’x 22.5’, 20’ EGL, SAG mill and provide the power draw at variable speeds but fixed loading conditions.The power draw and mill torque of this mill at 8% ball charge and 28% total loading (Highlighted) is shown below as Figure 1, at variable speeds."

Jan 1, 2007

The Ocean Drilling Program (ODP) is the largest international geoscience project in the world, and the state-of-the-art drill ship, the JOIDES Resolution, is permanently at sea. Each year there are six scientific cruises (legs) which each last approximately two months. These legs are designed by geoscientists from the nineteen countries that subscribe to ODP.Australia and Canada presently share ODP membership under the banner of the AUSCAN Consortium. The benefits of Australia's involvement in ODP include internationalisation of Australian geoscience, advanced graduate training, and unique scientific investigations of the ocean floors in the Australasian region. In addition, visits to Australian ports by the ODP drill ship, the JOIDES Resolution, contribute up to $2 million per visit to the local economy. Amongst the many other aspects of ten years of scientific drilling, OOP has significantly contributed to our understanding of hydrothermal processes on the seafloor. To date, three hydrothermal sites have been drilled to date by the OOP, Snakepit (MAR), Middle Valley (Juan de Fuca Ridge) and TAG (MAR). Two more hydrothermal sites are scheduled for 1996.

Jan 1, 1995

The conclusions reached by den Tex after a study of the fabric of some rocks from Broken Hill have been used to support the epigenetic hypothesis for the origin of the ore, first by Edwards (1959, p. 70) and then by Stillwell (1962, p. 131) in his criticism of Segnit's (1961) views. Den Tex claimed that the petrofabric study provided "independent evidence that the ore, at least in its present form, post-dates all events of a diastrophic nature in the area concerned".Repetition of this claim by Edwards and by Stillwell and the lack of any criticism of den Tex's work for more than three years implies its general acceptance by geologists in Australia. Therefore it appears necessary to examine parts of den Tex's paper in detail to show that his, conclusions are unwarranted. The major weaknesses in his study are that1. the petrofabric study was inadequate to warrant any major conclusions, and2. the petrofabric data allow alternative conclusions.Den Tex made a single visit to the field, collected six carefully selected specimens and presented quartz and· biotitepetrofabric diagrams for two specimens, quartz-diagrams alone for three more and included three diagrams of the orientation of c-axes and fractures in one specimen. It is not reasonable to come to firm conclusions about the origin of such a complex area as Broken Hill on such inadequate data, despite den Tex's claim (p. 87, lines 22 and 23) that "a thorough investigation of the quartz-fabric of the wall rock was undertaken".Den Tex's interpretation of each diagram is open to criticism, and alternative (and to my mind, preferable) interpretations may be made. It is impossible to evaluate den...

Jan 1, 1962

By J. Daavittila, P. Jokinen, M. Honkaniemi

In the latter part of the 1980?s Outokumpu Chrome in Tornio, Finland, was in a situation when its twenty-year-old ferrochrome plant was becoming inefficient to sustain economically sound production. The company made extensive studies on the then available processing methods to find out the best possible processing route. As a result the whole plant was practically rebuilt and expanded. When equipment was proven in practical operation an application for FeMn production was developed. Now when Tornio FeCr-plant is considering the expansion the same type of exercise is to be performed with today?s challenges, which will be discussed in the paper. These challenges include increasing costs or decreasing quality of raw materials, increasing energy costs, stricter environmental regulations and demand of better working conditions. The possibilities to respond to these challenges will be discussed in the paper. The future and continuing development with FeCr includes the better utilization of process dusts and a lower consumption of energy. By adapting the latest automation tools to better control of the process even higher efficiencies can be achieved with present technology. New processes are considered for development in the future and some possible technologies will be described.

Jan 1, 2004

By J. R. Nettle

The development of a process for upgrading offgrade titanium metal by electrorefining in molten salt led to an investigation of the electrotransfer characteristics of selected metals when alloyed with the titanium to be refined. Previous tests on seven binary titanium alloys showed that the degree of transfer of the alloying constituent depends on the constituent and on the operating procedurese.5 This report describes tests on electrorefining ternary mixtures of titanium with selected metallic elements. Ten alloys were prepared from high purity titanium and 2-1/2 percent of each of the metal pairs selected from the same elements used in the binary study; manganese, vanadium, chromium, zirconium, tin, molybdenum, aluminum. Operating variables were similar to those investigated in the binary alloy study that gave minimum alloy metal transfer. The data presented indicate the transfer characteristics of the various metals and combinations tested relative to each other.

Jan 1, 1962

Mr. Murray said: Having recently returned from a visit to America, it may be of interest to members to hear something from me of the mining fields and metallurgical works which I had the opportunity of seeing, and the impressions which I formed concerning general practice and conditions there, as compared with our Australian standards in the mining industry, and in matters generally.The most striking feature of the North American continent is thehuge plan upon which Nature has built, the multiplicity of immense mountains, rivers, and lakes, the snow-covered tops of the former forming reservoirs for the latter during the summer months, being most impressive to the Australian visitor. Starting from Vancouver I travelled east for over 500 miles through the wonderful Canadian...

Jan 1, 1927

By Thomas M. Barczak

State-of-the-art longwall roof supports provide effective strata control, but failures of these support systems still occur. To identify failure mechanisms and the impact these failures have on the safety of the support system, the U.S. Bureau of Mines has been conducting research on shield mechanics in the Bureau's unique mine roof simulator, as well as field studies of in situ support loading and investigations of longwall failures, Three types of failures are discussed: (1) inadequate support capacity, (2) structural failure, and (3) instability. Hypothetical situations with proposed courses of action and case studies of actual longwall failures are described. This information is intended to assist the Mine Safety and Health Administration (MSEIA) and industry mining personnel in safety evaluations of longwall roof support systems.

Jan 1, 1989

By Felix du Breuil

Contract H0177044 included three objectives; (1) consolidate, maintain, and distribute information on STE approved lighting systems; (2) develop and present one-day seminars on underground mine lighting; (3) determine direct labor and hardware costs associated with the installation of mine illumination systems. All objectives were completed with results as follows: Task I - A file containing 1350 Statements of Test and Evaluation (STE) for all types of underground equipment was developed and publicized throughout the coal fields, A total of 40 requests for STE information was received and processed. Task II and III - A series of 50 seminars was scheduled and presented to 942 attendees throughout the coal fields. The seminars were well received and attendees indicated the information presented would be helpful in bringing their equipment into compliance. Holding a series of seminars in the coal fields, instead of a few in population centers, was favored by attendees. Task IV - Installation cost data obtained on 415 lighting systems indicate that the factors which most affect installation costs are higher hardware cost for DC powered systems and slightly higher manpower requirements for systems installed underground. Based on these data, the total cost to industry of retrofitting existing underground equipment could range up to $50 million.

Jan 1, 1979

By Luis Castelli, Aldo Bonomelli, Giselle Schifferli, Claudio Zamora

"This paper introduces the operational concept and the description of a multi-site Remote Support Center for knowledge management and long-term process performance improvement.This centralized Support Center provides real-time monitoring of open-platform process automation systems, and on-line access to process data and control applications information for multiple sites.Considering that process automation is a key enabler to business performance improvement, sustaining effective performance benefits over time becomes essential. Unfortunately, changes in manufacturing process dynamics, technology obsolescence and in plant operational practices cause the control strategies to lose their effectiveness over time unless their performance is periodically evaluated, and if required, tuned to the new process conditions.A new concept in process automation is proposed through the addition of a new control loop based on performance analysis methodology which is intended to feedback process and automation operation information to system and process specialists, allowing for continuous manufacturing process improvement and sustainable production benefits through effectual control strategies.A remote support center can play a key role in the delivery of such services, by providing the base platform from which a comprehensive process overview and a centralized knowledge database can be executed and additionally, as an enabler for plant operational practices change.INTRODUCTIONA Benchmark on Automation Level in Copper Concentrators conducted by AMIRA in 2004, reported that the Codelco divisions scored below their peers in several categories.Codelco had thereafter been looking for a new automation concept, and had focused on process automation as a key enabler for process manufacturing and business performance improvement. The final decision was to create a strategic alliance with a world-class automation technology provider.The traditional approach based on isolated automation solutions/projects, showed that the control strategies benefits were decreasing progressively over time, because of the on-going need to adapt the control models to the ever-changing process conditions and different plant operational practices. Another consequence of this traditional approach was the wide variety of technologies and automation systems deployed in the different plant sites, with no common automation standards, and with low opportunities to transfer knowledge or practices."

Jan 1, 2010

By Betty L. Gibbs

Geologically simple deposits can be modeled quickly and easily with inexpensive gridding and mapping software. Hundreds of mines around the world use RockWorks99 and Surfer 7 for generating contour maps, producing log plots and cross sections, and performing other useful geological calculations. These programs are used by many mining operations as their only modeling and graphical software or they are used in conjunction with larger systems. The investment in learning time is low and the programs produce reasonable quality results with standard computing equipment. RockWorks99 and Surfer 7 provide a good level of capability while maintaining high quality technical integrity. Both programs are used for many applications in mining, oil and gas, environmental and other fields that require analysis of spatial data.

Jan 1, 2000

By M. A. Barakat

"Adsorption of heavy metal ions specifically, Cu(II), Zn(II), Mn(II), and Cr(VI) from aqueous solution on synthetic 4A Zeolite was evaluated. The 4A zeolite was synthesized previously by dehydroxylation of low grade Kalabsha Kaolin at 800 °C, and reacted hydrothermally with 2-4 M NaOH solution at 100 °C for 2h. The adsorption capacity of the metal ions were found to be strongly dependent on pH and initial metal ion concentration. At the optimium conditions the adsorption capacity decreased in the order Cu(II) > Zn(II) > Mn(II) > Cr(VI) ions. Almost complete adsorption was achieved for both of Cu(II) and Zn(II) ions at pH > 6, while the adsorption capacity for both Mn(II) and Cr(VI) was 96, and 55.3 % at pH 11 and pH 3, respectively. The results also showed that the grain size of the 4A zeolite has a little effect on the adsorption capacity. The experimental data was compared with two adsorption isotherms, Langmuir and Freundlich isotheroms. The results showed a good agreement of the Langmuir plots with the experimental data.1. IntroductionSeveral industrial wastewater streams may contain heavy metals such as Cr, Cu, Pb, Zn, Co, Ni, Mn, etc. including the waste liquids generated by metal finishing or the mineral processing industries. Heavy metals are considered hazardous pollutants due to their toxicity, even at low concentration, and nonbiodegradability. Increasing level of heavy metals in natural water bodies poses a serious threat to all living species including humans. It is, therefore, essential to reduce the heavy metal concentration in effluents/wastewater before it is discharged into the water bodies [1]."

Jan 1, 2008

By Walter W. Kaufman

The braking performance of underground, rubber-tired, coal mining vehicles is evaluated. Surveys of mining equipment and braking manufacturers and underground stopping tests are discussed as they relate to this evaluation. Stopping performance recommendations are proposed.

Jan 1, 1977

By Kadri Dagdelen

Design of the ultimate pit limit to direct long range mine planning has been a celebrated problem in the mining industry, and in mining academia, since 1965. Although many papers have been presented on this topic, even today, there is not a single solution technique which is widely accepted and considered universally best. Many philosophical differences exist among the pit planners concerning the use of different methods and it appears that resistance is very strong towards accepting other techniques if you are a believer in one. Whatever the case might be, the pit parameterization technique for the ultimate pit limit design is the latest and takes a different approach than its predecessors. There are already a number of papers which discuss the concepts involved (Francois-Bongarcon, 1976; 1978; 1980; 1981); however, the aim of this paper is to fill in some of the gaps which are thought to be missing in the previous discussions and, in addition, to present the recent research done on the subject at the Centre de Geostatistique de l?Ecole de Mines de Paris in Fontainbleau, France. This paper is divided into two parts. The first part will discuss practical aspects and interpretations of pit parameterization concepts with- out using mathematical or theoretical arguments; the reader who is interested in the theory should refer to Francois-Bongarcon (1978). The second part will present an approach to obtain a complete double parameterization of reserves using an inexpensive (computer costs) single parameterization algorithm. A case study of this approach is also included.

Jan 1, 1982

By Q. M. Huang

In 1979 our company undertook the project of infra-structural work of White Swan Lake Hotel, (International class ) Guangzhou. Visit to the site showed that it was situated at the riverside, covering an area of 54,000 M2 with 30,000 M2 of which reclaimed from Pearl River. The material used for reclamation was black sand which was dredged from the nearby riverbed. The sand had the properties of high permeability and very low internal friction. The basement of the building was 6.2 m below ground level and 3 m lower than the riverbed. Apart from the pile foundation, a diaphragm wall was to be constructed prior to the commencement of excavation work for basement. A feasibility study was carried out to determine the method of construction which would maximize utilization of the plants and equipment that were available in the execution of the aforesaid foundation works. This report concerns only the construction of the diaphragm wall and the performance of the plants employed. A detailed delineation of the construction method is herein discussed

Jan 1, 2010

By E. S. Moore

ALTHOUGH nickel was in use in alloys long before the Christian era, the metal was not discovered until 1751, when Cronstedt recognized it in niccolite from Sweden. The Chinese apparently used a nickel alloy, known as "pahfong" thousands of years ago and Persian coins dating farther back than 200 B.C. consist of a copper-nickel alloy similar to some of those now in use in coins. The pure metal was first prepared about 1775 and the metal was refined for commercial purposes some years later. The nickel industry did not attain much prominence until the ores in New Caledonia were discovered. Exports of ore from that country began in 1875 and since that date there has been an ever-increasing world output of nickel and a great expansion in the uses of the metal except during short periods of commercial and industrial depression. Previous to 1875, for a number of years, Norway was the chief producer, although the metal was mined also in Sweden, Finland, Italy, Germany, Austria, France, China, the United States and other countries. With the dis-covery of nickel deposits in the Sudbury district, Ontario, a new factor was introduced into the nickel industry and Sudbury has since become the overwhelmingly dominant feature in the world's nickel markets. Although nickel was first discovered in Canada as early as 1848 near the north shore of Lake Huron and nickel-copper sulfides were found in 1856 by surveyors working close to the present location of the important mine at Creighton, in the Sudbury field, it was not until 188.3 that any importance was attached to this field. In that year copper sulfide attracted attention where the main line of the Canadian Pacific railroad was being projected across Canada to the Pacific coast. Mining began near this discovery in 1889 but in the meantime operations had begun in 1886 in other parts of the field and by 1890 about 100,000 tons of ore had been raised. In the Sudbury field, as in Norway and at the old Lancaster Gap mine in Pennsylvania, the ore was first mined for its copper content and difficulty in the refining of the copper led to the discovery of the important proportions of nickel in the ore. No. 3 property of the Inter-national Nickel Co., now known as the Frood, the greatest deposit in the

Jan 1, 1932

By Richard H. De Voto

The McDonald gold project and two satellite gold deposits near Lincoln, MT were discovered in the early 1990s. They contain at least 307.9 t (9.9 million oz) of gold and 933 t (30 million oz)of silver. The McDonald gold deposit alone contains 223.9 t (7.2 million oz) of gold reserves that can be open-pit mined and processed by cyanide heap leaching at a projected cash operating cost of $6.10/g ($190/oz). The deposit is predominantly oxidized with no chance of acid production. It can be mined, operated and reclaimed with minimal permanent environmental disturbance other than the creation of an open-pit filled with a fresh-water lake that would support trout.

Jan 1, 2000

By V. V. Nazimko

Abandoned coal mines cause subsidence and structural damages. Shallow abandoned mines induce the most severe and harmful damages. In addition, they produce time-dependent subsidence which is difficult to predict. Backfilling of underground cavities with waste materials have been used to prevent the time-dependent subsidence or to mitigate its effect. However, this procedure is expensive. A new drill and blast technique has recently been proposed to prevent surface damage from time¬dependent subsidence over abandoned mines. It utilizes the principle that blasting in the caved rock and roof in the vicinity of a cavity will dilate the ground and create a self-supporting effect owing to increase in the volume. Physical modeling has demonstrated that artificial dilation of caved rock using the drill & blast technique creates positive effects due to the following sequence of events: the dilated rock creates a supporting effect for the suspended rock strata and reduces its span which decelerates 3.4 times the process of caving. The roof span is reduced by the next caved layer, which causes the hole boundaries to incline to each other. This effect converts the process of caving from a developing mode to a reduction mode. Finally, the sinkhole zone assumes a triangular shape with a negative angle of draw 64-700 in contrast to a rectangular shape of the chimney zone for natural caving. Vertical dimension of the triangular zone is 3.87 times of the room height. Final surface subsidence decreases at least 2.09 times; displacement 1.31 times, slope 2 27 times; curvature 3.42 times, horizontal strain 1 21 times in comparison to natural caving of the ground over an abandoned mine.

Jan 1, 1999