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By M. L. Baharani

Looking for an idyllic paradise that has investment and business potential as spectacular as the stunning views of mountains, the rich Ganesh Himal zinc-lead deposit exposed between 4,050 m and 5,000 m is the answer. Arising from the sea floor in a span of 55 million years, the enchanting Himalayas had remained one of the most potent factors influencing the Asian region. The challenges of the mighty Himalayas notwithstanding, it continues to provide opportunities for the humankind in optimum usage of the natural resources and sustainable development. Optimal management of natural resources in mountain areas through decision support tools offered by remote sensing will go a long way in realization of the Ganesh Himal Zinc-Lead Project. The authors have a real life endeavor spanning over 37 years in developing a mining industry in a mountainous region of Nepal and an attempt to integrate with the development of other natural attributes of the region. With rapid acceleration of science and technology, humankind has acquired power to transform his environment countless ways and on an unprecedented scale. While mineral resources are the pillars on which we have built industry and infrastructure, industrial countries in the North have been in the forefront of technological advancements, the developed countries of the South have been at the receiving end of exploitation of mineral resources worldwide. A relationship with natural environment, re-crafted by the civilizing impulse, to meet human demands are upcoming challenges for management of natural resource in sustainable manner for a livable world.

Jan 1, 2008

E. W. Stutchbury (Internationa~ Oombustion Aust. Ltd.) : Mr. Callcott made particular mention in his paper of erosion in primary air fans which are placed after the mill discharge. He adds that subsequent reduction in plant performance and resulting increased maintenance costs occur. It is generally assumed that this statement is substantially correct as the fan handles the complete output from the mill, but with modern materials, reduction in performance and subsequent .maintenance are not now a problem. This consideration of handling the pulverised coal in the fan is more than offset by the advantage of operating the mill under suction which results in cleaner operating conditions, simpler feeder arrangements and elimination of complicated seals on the mill.and feeder unit. It should be specially noted that whereas mill exhausters in the past have used chequer plate blades (sometimes with the addition of hard facing by electrode deposit) it is modern practice to provide fan blades of up to 1 in·. thick Ni-hard suitablyheat treated, with the circumferential section of the fan also in Ni-hard. By the use of this material large power...

Jan 1, 1957

By R. O. Burt

"IntroductionThe introduction to this section on gravity concentration indicated the wide range of equipment types that exist for the concentration of minerals, in what is the broadest size range of any concentration process.The equipment described in this chapter includes jigs, tables and sHme plant equipment. In contrast to the equipment described in the two succeeding chapters, this range of equipment, in nearly every instance, superimposes a mechanical movement on the fluid motion to effect separation of the valuable mineral from the waste mineral. The motion may be vertical Gigs), reversing (tables), or rotary (slime plants): however, in common they ""dilate"" the bed of particles to allow preferential settlement of the heavier particles.Description of Process UnitsJiggingJigging is the sorting of different minerals by stratification, based on the movement of a bed of particles relative to a fluid in a vertical plane.The basic construction of a jig is shown in Figure 1. Essentially it consists of an open tank filled with a fluid, normally water, with a horizontal jig screen at the top and with a spigot in the ""hutch"", or bottom compartment, for removal of heavies. The jig beri consists of a layer of coarse heavy particles (ragging) on the jig screen. This ragging is of a specific gravity between that of the minerals it is intended to separate.In operation the bed is made fluid by a pulsating current of fluid to provide stratification. On the upward or pulsion stroke the bed of ragging and slurry is normally Hfted as a mass, then as velocity of the upcurrent decreases it dilates, loosening the whole mass. On the downward or suction stroke it closes slowly again. The ideal is to control this dilation of the bed of material so that the heavier and smaller particles penetrate the interstices of the bed, while the larger heavies fall under a condition akin to ""hindered"" settling."

Jan 1, 1989

By Ralph J. Holmes, Victor Sharp, Steven J. Spencer, Kevin J. Davey, Jonathan J. Campbell, Peter L. Phillips, David G. Barker

"Improved measurement tools for monitoring and control of AG/SAG mill performance have a high level of interest in industry. Historically, acoustic emission monitoring has been widely used on SAG/AG/ball mills and hydrocyclones to provide new information on the conditions inside these devices affecting their performance. The current work was focused on a new technique using surface vibration monitoring of a number of pilot-scale and production-scale AG/SAG mills to yield insights into the events occurring in the mills. The development of relationships between signal analysis outputs and mill operating conditions can be used for soft-sensor measurement of mill process variables. The technique used an array of accelerometers mounted on the mill lifter bolts linked to a fast data acquisition system which monitored the surface waves generated during operation. Details of the system are presented. Mill operating variables were adjusted systematically to provide a wide range of operating conditions for surface vibration signal collection. The experimental approach is discussed.The signals acquired during the experiments were analysed using a range of techniques. The results show that strong relationships exist between measured vibration power (both total power and within certain frequency bands) and mill load level/power and mill speed. A new method for extraction of power spectral density and band power information on features of interest in a mill rotation cycle is also presented.These results show that single sensor analysis information from the surface vibration system can be used as soft sensor inputs for monitoring process variables such as mill load that until now, have not been reliably measured. System outputs also show considerable promise in the area of condition monitoring. An example of the signal analysis output is presented showing elevated vibration levels in an area with higher resultant wear. Eventually, it is considered that outputs from this system for process variable and wear condition monitoring will be key new inputs to an online AG/SAG mill monitoring and control system."

Jan 1, 2003

By D. C. Fleck

Electrorefining yttrium from selected low-melting yttrium--base alloys is investigated, and various halide systems are studied as potential electrolytes for use in preparing low-oxygen yttrium by electrorefining unalloyed yttrium. Yttrium cathode products having significantly less metallic impurities than the anode materials were prepared from alloys containing nickel, iron, and manganese by electrorefining in LiCl-YC13 electrolytes at 900° to 1,000° C. Yttrium-copper and yttrium-magnesium alloys are not suitable as anode feed materials, An evaluation of chloride, fluoride, bromide, and mixed chloride-fluoride electrolytes showed that cathode products containing much less oxygen than the anode material can be obtained in the fluoride and mixed chloride-fluoride systems. Initial cathode current density has no apparent effect on the purity of the products obtained in both phases of the investigation.

Jan 1, 1973

By N. Kuyucak

"Acid mine drainage (AMD) is one of the most significant environmental challenges facing the mining industry worldwide. It occurs as a result of natural oxidation of sulphide minerals contained in mining wastes at operating and closed/decommissioned mine sites. AMD may adversely impact the surface water and groundwater quality and land use due to its typical low pH, high acidity and elevated concentrations of metals and sulphate content. Once it develops at a mine, its control can be difficult and expensive. If generation of AMD cannot be prevented, it must be collected and treated. Treatment of AMD usually costs more than control of AMD and may be required for many years after mining activities have ceased. Therefore, application of appropriate control methods to the site at the early stage of the mining would be beneficial.Although prevention of AMD is the most desirable option, a cost-effective prevention method is not yet available. The most effective method of control is to minimize penetration of air and water through the waste pile using a cover, either wet (water) or dry (soil), which is placed over the waste pile. Despite their high cost, these covers cannot always completely stop the oxidation process and generation of AMD. Application of more than one option might be required.Early diagnosis of the problem, identification of appropriate prevention/control measures and implementation of these methods to the site would reduce the potential risk of AMD generation. AMD prevention/control measures broadly include use of covers, control of the source, migration of AMD, and treatment. This paper provides an overview of AMD prevention and control options applicable for developing, operating and decommissioned mines."

Jan 1, 2002

By Richard F. Lynch, Frank E. Goodwin

"The development of Galfan, a new generation 95% zinc-5% aluminum-mischmetal alloy coating for steel, offers opportunities for greater fabrication flexibility and upgraded corrosion performance in automotive applications. The formability of Galfan is equivalent to that of electrogalvanized steel, based on laboratory tests and automotive component fabrication. Corrosion resistance of Galfan exceeds that of hot dip and electrogalvanized, including performance in automotive industry tests. Automotive production applications for deep drawn and stamped components in France and Germany are based on the ability to meet dual performance requirements for upgraded formability and corrosion resistance. The first U.S. Galfan application was on 1985 model Ford cars and light trucks for transmission oil cooler lines which has now expanded into a number of power steering tubing uses. IntroductionContinuing requirements for improved vehicle performance coupled with the ever present need for reduced cost have spawned the development of a number of new coated steel products. Among this new generation of coated steels is Gaifan™, a 95070 zinc-Solo aluminum-mischmetal hot dip alloy coating. Galfan exhibits particular promise for automotive use based on broad fabrication advantages and upgraded product performance(I ),The unique characteristic of Galfan is the key combination of greatly improved formability with much longer corrosion life. Galfan provides significantly better formability than any other hot dip coating. Testing shows that formability is limited primarily by the steel substrate to which the Galfan coating is applied. Galfan exhibits excellent resistance to flaking and microcracking during commercial forming operations. The result is the elimination of unnoticed damage to the coating which would show up later as premature rusting on the finished product."

Jan 1, 1987

By Arthur Nomann

Recording instruments may be conveniently described under the headings of: (1) geophones, (2) amplifiers, (3) recording cameras, (4) miscellaneous parts. Geophones Geophones or seismometers are actuated by slight earth movements, and generate electrical currents, which are amplified and recorded. In all geophone desigm there is provision for differential movement between parts of the mechanism and the signal voltage is generated as a function of this differential movement. The part that conforms to the movement of the ground is called the support, and the part that remains more nearly stationary with respect to more distant unactuated parts of the earth is called the steady mass. The mechanical period of the geophone is the time required for an oscillation of the steady mass after an initial impulse is given it, and is determined by the effective stiffness of the spring joining the two parts together in relation to the weight of the suspended part. Geophones have been used with frequencies varying all the way from less than 10 cycles per sec. to several hundred cycles per second. Those with a natural frequency of less than, say, 100 cycles

Jan 1, 1940

By Arthur Nomann

Recording instruments may be conveniently described under the headings of: (1) geophones, (2) amplifiers, (3) recording cameras, (4) miscellaneous parts. Geophones Geophones or seismometers are actuated by slight earth movements, and generate electrical currents, which are amplified and recorded. In all geophone desigm there is provision for differential movement between parts of the mechanism and the signal voltage is generated as a function of this differential movement. The part that conforms to the movement of the ground is called the support, and the part that remains more nearly stationary with respect to more distant unactuated parts of the earth is called the steady mass. The mechanical period of the geophone is the time required for an oscillation of the steady mass after an initial impulse is given it, and is determined by the effective stiffness of the spring joining the two parts together in relation to the weight of the suspended part. Geophones have been used with frequencies varying all the way from less than 10 cycles per sec. to several hundred cycles per second. Those with a natural frequency of less than, say, 100 cycles

Jan 1, 1940

By Linneas W. Laage

MFIRE is a computer simulation program that performs normal ventilation network planning calculations, and dynamic transient state simulation of ventilation networks under a variety of conditions. The program is useful for the analysis of ventilation networks under thermal and mechanical influence. MFIRE simulates a mine's ventilation system and its response to altered ventilation parameters, external influences such as temperatures, and internal influences such as fires. Extensive output enables detailed quantitative analysis of the effects of the proposed alteration to the ventilation system Network simulation using digital computers has become widespread throughout the mining industry in recent years. However, as the sophistication of the simulator increases (MFIRE, for example), the complexity of input data requirements and interpretations of results requires more skill and knowledge from the users. Perhaps the most difficult part of using MFIRE is to construct the data set describing the mine's physical layout and its ventilation properties. The initial attempts to get the data set running often reveal unknown or ignored aspects of the mine's ventilation.

Jan 1, 1995

By Estefania Aramayo, Jhon Silva, Todor Petrov

Blasting is one of the most critical activities in a mining operation. Nowadays, many quarries have to follow a considerable quantity of environmental restrictions that drive the need to improve the conceptualization, design, procedures, and execution of the blast to comply with all regulations. Airblast is one of the variables required to control when blasting. Airblast is an unwanted side effect of blasting. Airblast is defined as an airborne shock wave resulting from the detonation of explosives. Traditional methodologies used for assessing the overpressure produced by the airblast are based on empirical approximations that require the collection of a series of produced airblasts before they can be used as a predicting tool. Once the data is available, regression analysis methodologies are used to find the constants of empirical laws that, in most cases, establish the relationship between the distance and the weight of explosives used in the shot (scaled distances laws). If using the traditional methodologies, the quality, and representativity of the scaled law established for a particular project are determined in terms of the correlation coefficient; in most cases, the models and their use as a predicting tool are questionable (very low correlation values).

Feb 6, 2023

By Karl J. C. Harries

"11.1. INTRODUCTIONA royalty is the most common form of interest retained by an owner who is disposing of his property or by a joint venturer who ceases, voluntarily or otherwise, to participate in the joint venture.1 Rarely does a non-participating party have a direct interest in the property and/or assets of a project, except during the period when a non-participating joint venturer may be having his interest diluted.2 In fact, it is most unwise to permit a non-participating party to have such an interest. It may give rise to significant problems that could prevent or substantially delay the development of an orebody and require a considerable amount of time, effort, and money to correct.3In negotiating a royalty, it is important to be aware that there is no law or convention that says, “You just don’t do that in a royalty agreement.” As with any agreement, inventiveness and flexibility on the part of the negotiator are not just assets, but virtual necessities. It is also for this reason that it is essential to read the royalty provisions, particularly the definitions, fully and carefully, especially if you are the recipient. On the other hand, if your inventiveness and flexibility cause your accountant to question the advisability of one of your ideas, pay close attention to him.4 He will, no doubt, have had experience with many royalties, and no competent professional adviser disparages a client’s ideas without good reason. Besides, he will probably be the person who will be determining the royalty or certifying the determination of it. At the very least, he will be auditing your general financial statements, which must, of course, reflect the royalty determination. Heeding his advice not only may make the determination easier but also will probably save you money in professional fees later on. Nevertheless, do not simply accept his comments or recommendations without understanding what they mean, why they have been made with respect to your royalty agreement (sometimes professionals have comments that they make as a matter of course and, even though they may be valid, you should require them to be justified to you), and how they will affect your royalty determination.It is surprising how many corporate payors insist that their standard royalty provisions5 be used as a matter of policy, thereby effectively tying the negotiator’s hands. It is even more surprising, and to professional advisers frightening, how many of the senior employees who insist that such a policy be adhered to, virtually without variation, do not know what is in the standard provisions and would be hard-pressed to explain them to a property owner. If standard provisions are appropriate, by all means use them, but do allow experienced and sensible negotiators some flexibility and make sure that everyone within the corporation who may have to use such provisions – negotiator and supervisor alike – knows what they contain and why they are as they are. For example, there are often good and convincing reasons to describe a deduction in a certain way or to include a certain specific type of deduction. On the other hand, quite often the answer to the question “why?” is that “it has always been there”; this is, or should be, an unacceptable answer. In any event, if you, as the negotiator, appear to know what you are talking about, are familiar and comfortable with your royalty provisions, and are backed up by your boss with the same words or reasoning, a property owner cannot help but be satisfied that you are knowledgeable, even if he still does not agree with your provisions. Finally, if you do use standard provisions, make sure that they are reviewed and updated regularly."

Jan 1, 2003

By P J. Hommert, D S. Preece

"Commercial development of the United States Oil Shale reserve will require substantial amounts of mining. In fact, even a modest 500,000 barrels per day industry requires a mining effort equivalent to nearly half of the current U.S. coal mining industry. Obviously, mining efforts on this scale will benefit from technological advances. There are a number of areas where advanced technology could impact mining. These include continuous miners, shale transport systems, and blasting. This paperexamines recent developments in computer modeling of blasting and assesses the likelihood of these advances being applied to practical oil shale mining problems."

Jan 1, 1989

By C. J. Newman

Before 1995, the smelting process at the Kennecott Utah Copper Corp. (KUCC) smelter consisted of Noranda reactors and Pierce-Smith converters. When considering expansion, it was decided that the existing process would not lend itself to a program geared toward processing the total output of copper precipitate and copper concentrate from KUCC mining and concentrating operations. During 1989 and 1990, several smelting options were evaluated. The final selection was the Outokumpu flash smelting process, coupled with the new Kennecott-Outokumpu flash converting technology. Facilities were designed and installed to process 1 Mt/a (1.1 million stpy) of copper concentrate, with the ability to expand to 1.2 Mt/a (1.3 million stpy). The smelter facility that used the Noranda technology was shut down in May 1995. The flash smelting furnace operation began in June with the flash converting furnace start-up a few weeks later.

Jan 1, 1999

By P. Dhar, H. R. Kota, M. Thornhill

Precipitated calcium carbonate is used as a filler and coating material in the manufacturing of paper because of its high brightness and light scattering characteristics. However, beneficiated calcite has similar potential, given the fact that the industrial specifications are already achieved. For paper industries, the requirement is that the desired product should be pure and have a brightness of 93 to 95 percent. A very-high-grade calcite deposit of around 92 percent is located in the north of Norway, which is used as the raw material for ground calcium carbonate (GCC) feed for the paper industries. There is a substantial amount of calcite resource, which has pyrite and pyrrhotite as major impurities. These sulfides, even when present in minor concentrations, impart color to the end product (paper). Removing these minerals is estimated to increase utilization of the deposit by 10  percent, which represents several million tonnes of calcite marble. Due to the requirement for environmentally friendly reagents and chemicals by the mineral industry, fatty di-amines are being tested for pyrite and pyrrhotite flotation. The interaction mechanism of diamine with the main components of the ore were studied and optimum conditions for removal of sulfide impurities are outlined.

A computer program for the static load analysis of linear elastic structures is presented. It is the product of a two-year project for the development of a efficient program for the analysis of mine-type structures. The report is divided into two parts. The first part explains the general method of analysis, the computer program organization and the most significant numerical techniques used. The second part is a user manual for the computer program. The FORTRAN IV computer program deck and example problems were transmitted separately to the sponsor. Request for a copy of the program should be directed to the Bureau of Mines, Denver Mining Research Center.

Jan 1, 1972

By Jaeheon Lee, Junmo Ahn, Jiajia Wu

In this project, low grade copper ore samples were obtained from two mining sites in the US, and they were chalcopyrite-rich (sample A) and conichalcite-rich (sample B) ore. Copper grades were 0.6% and 0.4% for the two samples, A and B, respectively. Leaching experiments were conducted by bottle roll tests for 24 hours, and various lixiviant systems were applied. Methanesulfonic acid (MSA) and glycine were used as alternative lixiviants to sulfuric acid. Oxidants including ferric ion and hydrogen peroxide were tested. The results showed the copper extraction of sample A increased after adding 1 g/L ferric ion in sulfuric acid and MSA solution, from 20% to 36%, but further increase was not observed with higher ferric ion concentration. The copper recovery increased significantly with H2O2 concentration, and over 80% copper recovery was obtained with 10% H2O2. For sample B, the copper dissolution kinetics were relatively fast and reached the maximum value in five hours. Around 60% copper were extracted in sulfuric acid and MSA solution. Copper recovery slightly increased after adding ferric ion and H2O2. Glycine is a weaker lixiviant for both samples, the copper extractions were 36% and 4% respectively. INTRODUCTION Chalcopyrite is the most abundant copper sulfide mineral on earth, and it is one of the most refractory copper minerals regarding chemical processing. The declining copper grade and depletion of copper oxide deposits stimulate the development of hydrometallurgical process to extract copper from chalcopyrite. The dissolution of chalcopyrite by ferric ion is normally illustrated as Equation (1) and (2) (Dutrizac & MacDonald, 1974): CuFeS2 + 4Fe3+ → Cu2+ + 5Fe2+ + 2S0 (1) CuFeS2 + 4Fe3+ + 3O2 + 2H2O → Cu2+ + 5Fe2+ + 2H2SO4 (2) However, slow kinetics are usually observed from chalcopyrite leaching at ambient temperature and pressure. Researchers attribute the slow kinetics to passivation during chalcopyrite dissolution, and different passivation products are also proposed (Klauber, 2008). In recent years, many efforts have made to develop new methods to extract copper from chalcopyrite, such as utilizing bacteria or stronger oxidant (Zhao et al., 2015; Ruiz-Sánchez & Lapidus, 2017).

Jan 1, 2019

By E. R. Cole

Laboratory heats of an 80 percent copper high-leaded tin-bronze alloy, similar to Brass and Bronze Ingot Institute (BBII) alloy 3A, were made with reduced tin content to determine whether an alloy comparable to BBII alloy 3A could be produced using less tin to aid in conserving this strategic metal. The tin content was lowered from 10 percent to 8 percent and 5 percent (nominal values), respectively, and the reduction in tin was offset by either increasing the lead content or adding zinc. Mechanical properties, machinability, and corrosion characteristics of the resultant alloys were investigated, and the mechanical properties were compared with BBII typical values and American Society for Testing Materials (ASTM) minimums for high-leaded tin-bronze alloy. Results indicate that the tin content of this alloy could be reduced approximately 1 percent (difference between the 8.4 percent actual tin composition obtained and the 9.3 percent BBII minimum) without seriously affecting the desired properties. Results also show the tin content could be reduced without significantly increasing the chances of rejects for mechanical property failures, which might result from normal variations in the casting process.

Jan 1, 1972

Electroosmotic Dewatering and Consolidation of Mineral Waste Tailings

Sep 13, 2010

By WU Jian-hui

Keywords: metallic material; nickel powder; thermal decomposition; precursor; fibrillar powder; nanometer scale; passivation treatment The precursor thermal decomposition process of fibrillar nanometer scale nickel powder and passivation treatment of obtained powder are investigated, and the composition and morphology of the products are characterized by use of IR, TGA/DTA, XRD and SEM. The results show that the precursor morphology is a decisive factor to the product morphology of the nickel powder. The morphology of the product derived at low decomposing temperature is irregular. The nickel powders produced at the temperature higher than 480 coheres seriously. The product particles are reunited with the decomposition time prolong. The powder prepared under the optimal condition is fibrillar like woolen yarn; the grain diameter is less than 50nm.

Jan 1, 2005