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By Veerendra Singh, NILAMADHABA SAHU, ARIJIT BISWAS

Manganese (Mn) ferroalloys are chiefly consumed in the steelmaking process as a deoxidizing agent or as an alloying element to produce high-quality steels. These alloys are typically produced in a submerged arc furnace using coke, fluxes and manganese ores of a specific manganese/Fe (Mn/Fe) ratio. Preferred-grade manganese ores should have Mn content greater than 46 percent and Mn/Fe content greater than 5 to produce commercial-grade, high-carbon ferromanganese [1]. Selective mining of high-grade Mn resources has created a scarcity of these resources, which is emerging as a major challenge for the manganese and steel industry. Manganese ore resources are mainly distributed in South Africa, with about 32 percent; Ukraine, with about 17 percent; Australia, with about 17 percent; and Brazil, India, China, Gabon and Mexico, with lesser amounts.

By Miles L. Silberman

Three major suites of igneous rocks were erupted in the Great Basin in middle and late Cenozoic time. The first, most likely, resulted from sub- duction of a Pacific plate (Farallon plate) beneath the North American plate, resulting in eruption of andesitic rocks in the northern Great Basin between 42 and 43 m.y. ago. Between 34 and 17 m.y. ago, igneous activity migrated to the southwest, largely as eruption of volumincus rhyolite-quartz latite ash-flow sheets, ending about 17 a.y. ago with the onset of crustal extension and north-south-trending Basin and Range (rift) faulting. The second volcanic suite erupted between 17 and 8 m.y. ago in the northern Great Basin; is mostly basaltic or bimodal basalt-rhyolite. The third volcanic suite consists of andesitic and rhyolitic lavas and some basalt erupted between about 22 to 6 m.y. ago in the western Great Basin along the northwest-trending Walker Lane fault zone. Hydrothermal ore deposits are associated with all suites of igneous rocks, but the largest production has come from mines associated with andesitic rocks of the third (western Great Basin) suite. The oldest (34 to 42 m.y.) andesitic rocks (first suite) of the northern Great Basin have produced some large deposits; slightly younger silicic rocks of this suite are mostly barren. Many small ore deposits are associated with the 17- to 8-m.y.-old basalts (second suite) of northern Nevada.

Jan 1, 1976

By V. L. Ketellapper

This paper discusses the technical issues and stakeholder collaborative processes which resulted in achieving a balance between the reclamation of abandoned mine sites, providing affordable housing, and preservation of open space at the French Gulch Site. Through this process, it was discovered that mine site reclamation would need to be conducted in conjunction with two priorities for community sustainable development: providing affordable housing for locals who work in the resort town of Breckenridge, and open space preservation. It was found that conducting these activities concurrently would result in providing resources necessary to complete mine site reclamation. The first phase of the affordable housing development is almost completed. This development resulted in redevelopment of mining impacted lands and was recognized by the U.S. Environmental Protection Agency (EPA) with a National Smart Growth Award in 2002.Negotiations are also underway to preserve the remaining 1,800 acres of land held by the mining company as open space. This transaction will in turn provide resources to address water quality issues associated with mine discharges.

Jan 1, 2004

By E. Hughes, D. Akers, D. Stopek

The Upgraded Coal Interest Group (UCIG), focuses on clean, low-cost options for coal-based power generation via pre-combustion, co-firing and reburn options. Its mission is to preserve and expand the economic use of coal for energy. By reducing the fuel costs and environmental impacts of coal-fired power generation, existing units become more cost effective and thus new units utilizing advanced combustion technologies are more likely to be coal-fired. Two great forces are reshaping the power generation industry, the Clean Air Act Amendment and deregulation of generation. The Clean Air Act Amendment is forcing change by making it necessary for power producers to plan for reducing emissions of sulfur and nitrogen oxides and possibly trace elements. At the same time, deregulation of generation is forcing utilities to focus their attention closely on the short term impact of any change on cost of power. Fuel is a utility's largest cost element; maximum fuel flexibility will be a utility's best weapon in an environment of rapid change. In a regulated environment, a utility was limited in how involved he might get into fuel supply, in a purely deregulated environment he need only be guided by the impact on the bottom line. It is clear that these two forces will promote a close look at factors such as coal upgrading which can have an impact on the availability of low sulfur coal or emission of NOX and trace elements.

Jan 1, 2000

By Matthew Deutsch

A common casualty of modern openpit mine optimization is the assurance that the resulting design is actually achievable. Optimized mine plans that consider value and a bare minimum of precedence constraints do not, in general, translate into practical, operational mine designs that can be used in the field. Ultimate pits may come to a sharp point at the bottom. Schedules may require taking small parcels of material from many disparate areas of the pit in a single period, and grade control polygons may be ragged, narrow and not minable with realistic equipment. In this paper, these three fundamental openpit mine optimization problems are addressed by encoding them as maximum satisfiability problems. Maximum satisfiability provides a useful framework for problems that are nonlinear and may guarantee the optimality that metaheuristics cannot.

By W. M. Hart

Business Process Improvement (“BPI”) Change to Survive “It is not the strongest of species that survive, nor the most intelligent, but the one most responsive to change.” [Charles Darwin] “If you want to understand something, try to change it.” [Kurt Lewin, social scientist] Many companies have tried one or more process management initiatives. Each effort may help develop a culture that is more receptive to change. Executive Management needs to be unwavering in support of change with systems and structures, staffing, development of people, measures, with incentives and rewards. General Electric developed principles for quality change management that are necessary for effective, continuing Business Process Improvement (BPI). Change Acceleration Process (“CAP”) One of the tools General Electric developed has been used successfully by companies around the world in a wide variety of industries. This tool, named Change Acceleration Process (“CAP”), is designed to improve acceptance of change. Acceptance is the method by which the creative energies of the workforce can be fully tapped. Over time, every employee receives CAP training at least once, and in many instances three (3) or four (4) times, and will work on one or more High Performance Teams. Thus, BPI can achieve and maintain its goals. The CAP tool focuses on: • Leading Change • Creating a Shared Need • Shaping a Vision • Mobilizing Communication • Making Change Last • Monitoring Progress • Changing Systems and Structures

Jan 1, 2006

By Richard Cole

The Energy Act of 1992 has many users of ac-induction motors eyeing premium-efficiency motors with mixed feelings and perhaps some confusion. When the October 1997deadline arrives for compliance with the1992 standards, the winners will be the environment due to reduced need for more power generating plants and the petroleum economy because of reduced dependency on foreign oil. But what will it mean for industrial users? The most obvious benefit is the potential for smaller electricity bills. Motors account for about 64% of the electricity consumed in the United States, at a yearly cost of $112 billion. Every 1% reduction in motor demand cuts 0.64%, or $716 million, off the industry wide bill. Higher efficiency motors also run cooler. This lightens the load on air-conditioning systems and further reduces plant demand. Lower total demand can lead to lower rates by helping to minimize peak-demand surcharges. As rates increase over time, these savings get bigger.

Jan 1, 1996

By I. Douni

The aim of this study is to synthesize hydrated compounds of calcium silicate (tobermorite) using as siliceous source perlite milling process wastes, containing more than 70% of SiO2. Calcium silicate hydrates are mainly used for construction of lightweight building materials, plasters, tiles and filters. The effect of temperature, time and particle size of perlite on the quality and composition of the solid product was studied. The solid products were characterized by X-ray Diffractometry, Differential Thermal Analysis and the amount of Acid Insoluble Residue. The synthesis of tobermorite was per-formed by the hydrothermal treatment of perlite waste with a saturated calcium hydroxide solution at a molar ratio CaO/SiO2 of 1, liquid to solid ratio 10 mL/g and 1% w.t. NaOH addition. Three experimental sets were performed. In the first series of experiments the synthesis temperature was kept constant at 205°C while the synthesis time varied from 0.5 h to 24 h. In the second experimental series the synthesis time was kept constant at 2 h while the temperature varied between 150°C and 245°C. In the third experimental set the temperature was 205°C and the reaction time was 2 hours and two perlite waste size fractions were used, a coarse (d50=18 µm) and a fine grained one (d50=8 µm). Reaction products consisted of semicrystalline calcium silicate hydrate (I) and crystalline Al-substituted tobermorite or a mixture of both. An isomorphic Si4+ ions substitution with Al3+ ions in the hydrated calcium silicate lattice was detected by thermal analysis. The experimental results show that good quality crystalline Al-tobermorite can be produced after 6 hours of autoclaving at 205°C or after 2 hours of hydro-thermal treatment at 225°C. Generally, the in-crease of synthesis temperature or time favors the crystallization of calcium silicate phases and enriches them in aluminum. The use of fine grain size perlite is more efficient for the hydrothermal synthesis of calcium silicate hydrates.

Jan 1, 2006

By F. G. Heivilin

There will be 3 billion people moving into cities by 2050. Permitting is both the biggest obstacle and the biggest opportunity for mining. The problem is not if we have the right minerals, but how we can permit and produce it in a ?Sustainable? manner. A ?Permit? and a ?Sustainable Development Plan? may soon be the same thing. How do we produce the minerals we need with: 1. The lowest possible carbon footprint. 2. Social license from community outreach by being a catalyst and not a problem in a ?Green World.? 3. Enhanced water supply during all stages of production. 4. Meeting requirements of our customers for service, quality, & cost. How important is it to have a complete ?Sustainable Development Program?? First, no plan is complete!!! It is a work in progress subject to continuous improvement. We need to work together to get the results we want. The goal of the world communities is to become carbon neutral by 2050. What is the mining community?s goal? Do we have one???? When a Clorox, Colgate Palmolive, Wal-Mart, Toyota, or Caterpillar buys a product, what are your chances of getting an order without a good program in place? The answer is it will be difficult or impossible shortly and you will be requiring the same thing with your suppliers. This is an opportunity if you are in the lead and it soon will be a necessity for most mining and processing companies requiring much extra effort to catch up. For some mines it was a necessity to get most of the SD plan to get permitted. The number of companies in the extractive industries with a full Sustainable Development Programs is expanding rapidly as shareholder demands for transparency continue to grow.

Feb 27, 2013

Although out of the ordinary, MINING ENGINEERING is pleased to present a few photographs that typify Western US mining activity during WWII. The photographs, taken by R.G. Zellers at Colorado mining operations between 1942 and 1946, were primarily intended for equipment manufacturers. The pictures capture scenes of hardworking miners during a time when output was essential to fuel a wartime effort. In addition to providing a rare opportunity to step back 40 years and view the equipment and activity common at the time, Zellers' skill with photo composition and his ability to obtain clarity in dimly lit underground operations gives viewers an acute awareness of the dampness and dirt of the mines, and a sense for the miners' limited working space.

Jan 6, 1983

By Lynn B. Hales

The Supervisory Computer System at Cities Service copper mine and concentrator at Miami, Arizona was installed at Pinto Valley in the spring of 1975. Design and specification [l] of the digital system was initiated jointly by key plant personnel at Pinto Valley and staff of Cities Service Research and Development Company. The Pinto Valley digital system [2] may be classified as a supervisory control system of hierarchical design. There are three fully independent satellite computers which retrieve and reduce the raw plant data from each of the three main operating areas - the primary crushing plant, the fine crushing plant, and the grinding and flotation plant. While the three satellite computers are core resident systems, the master computer is a disc-based operating system which also interfaces with a computer controlled on-stream x-ray analyzer system. Figure 1 illustrates the basic system configuration [3]. The software systems required to support a large system are quite diverse and vary greatly in function. The philosophy followed in dividing the software into three categories was designed to: 1) fully utilize existing process knowledge of technical staff; 2) delegate certain software tasks to outside sources already skilled and trained in software development; and 3) maintain final control over the design and operation of each system.

Jan 1, 1976

The speed and internal accuracy of today's electronic calculators can be utilized to write an efficient slurry calculation program. The calculator's input/output printing feature offers additional benefits for data organizing and record keeping. This program allows slurry calculations to be performed without the urgency of immediately transferring a calculated result onto a process flowsheet or specification sheet. The number of flowsheets required for some hvdrometallurgical processes means the number of process stream blocks or ladder diagram entries can become substantial. Slurry calculations for such projects tend to become repetitious and tedious, and the chances for errors increase both in calculation and data entry onto process documents. Using this program has minimized both types of errors. Checking process flowsheets is particularly expedient with the program because you may "walk" through the flowsheet on a weight basis, i.e., solids rate and solids density, and have the program verify and/or correct the volume entries, gallons, and specific gravities. The program was initially used on a beneficiation project to check some 500 data entry values on ladder diagrams covering seven process flowsheets. Numerous hand calculation errors were determined and corrected, and the time for completely checking and correcting the flowsheet ladder diagrams was substantially reduced.

Jan 4, 1981

By J. A. Lombardi

Acid-Minesite-Solutions (AMS) are defined as copper-containing pit lake, tailing pond, acid-mine-drainage, and heap and waste dump irrigation solutions. All of these solutions are characterized by copper, acid and water contents that have value as individual commodities. HW Process Technologies, Inc. (HWPT) has developed nano- and hyper-filtration membrane methods for the separation of copper and other base metals, acid and water from AMS. These treatments are collectively called HWPT?s Engineered Membrane Separation® (EMS®) systems. The EMS® method of copper recovery produces small volumes of higher-concentration copper solution from large-volume, copper-dilute AMS. A case study of the 4,000 gpm Cananea EMS®-AMS plant for the recovery of copper from an acid-pit-lake resource is described. The EMS® method of copper removal from AMD and tails pond waters has been bench-scale demonstrated and are described, complete with projected budgetary capital and operating costs. Additional treatments for the recovery of sulfuric acid and high-quality water from the permeate (membrane passing) waters for the above-described AMS treatments are presented, with budgetary capital and operating cost estimates. [ ]

Jan 1, 2009

By Halter L. Gould

Since the turn of the century there has been a marked increase in population, industrial and economic growth, and in energy requirements in the United States. During this time our energy needs have been met largely by natural gas and petroleum, but as our reserves of these materials are depleted, we are going to depend more and more on our large reserves of coal. The mining of coal for electrical power production has increased at a rapid rate during the past decade. Over half the coal produced in the United States in 1971 came from mines utilizing surface mining operations (Paone, et al, 1974). Surface mining is expected to increase as the rising cost of oil places more demand on coal for energy. About 57 percent of the coal reserves in the United States lie in the area west of the 100th meridian. About one-quarter of this can be mined by current surface methods. This would involve the disturbance of approximately 1.5 million acres (600,000 hectares). By the year 2000, projections indicate disturbance of about 200,000 acres, or 300 square miles, in the West. Mined areas receiving more than 250 mm of annual precipitation can usually be revegetated without irrigation if the spoils are properly shaped, the surface layer consists of suitable plant growth media, and proven techniques in rehabilitating disturbed rangeland are applied. Areas receiving less than 250 mm of annual rainfall or with high evapotranspiration rates pose a more difficult problem. Revegetation of these areas can probably be accomplished only with major inputs of water and good management (National Academy of Science, 1974).

Jan 1, 1978

By Phil Jones

"Dilution — planned and unplanned – remains a significant cost impairment in the mining process. A series of trials were held over a sixmonth period in fiscal year 2018 (FY18) that established the cost-benefit of new technology as it applies to the alignment accuracy of production drilling rigs in underground mining, thus confirming its ability to limit drilling as one of the causes of dilution. The trials identified three underlying factors affecting drilling accuracy, measurable by blast-hole deviation surveys of planned versus actual toe data. These were rig alignment error, collar location change/ error and in-hole deviation.The trials involved a comparison of existing rig setup processes and technology, with the new technology (Minnovare’s Production Optimizer system). The trials were undertaken in the same environment: the Cracow gold mine, an operating underground mine. The comparison first revealed the extent to which rig alignment impacts blast-hole deviation. Secondly, the new technology was proven to limit rig alignment error, thereby reducing average blast-hole deviation and increasing the number of holes drilled within tolerance by 160 percent.The increased accuracy reduced stope dilution by reducing over-break of subgrade ore. The new technology was implemented at Cracow during the latter half of 2018. Despite utilizing the new technology for just six months of the year, the mine recorded a 5 percent overall reduction in dilution for the full year compared to the previous year (FY17); from 22 percent down to 17 percent (a net decrease of 22.7 percent). Mine management attribute a significant proportion of this reduction to the new technology, along with sequencing and planning improvements. This opinion is backed by detailed stope reconciliation data taken during the trial from 28 stopes — representing 20 percent of the total tonnes mined during FY18. The data identified that stopes drilled using the new technology recorded 62.6 percent less average dilution."

May 1, 2019

By Lorraine Brandt Yde

This paper describes development of a cost report that is descriptive, logically oriented, and concise. Since the costs involved relate to mining, this reporting technique could help bridge any possible communications gap between "mining men" and computer personnel, at the same time giving the computer-oriented mining individual information to assist him in his job performance. As computers become entrenched in the mining world, meaningful report assimilation becomes a major task. No one should be more capable of defining required results than the man requesting a report. If he is able to clearly state his needs and has researched his problem, it will be reflected in the computer output. During 1970, The Anaconda Company's Berkeley Pit Operation, at Butte, Montana, received many different computer-generated equipment cost reports. Up to thirty-six different components for each type (class) of pit equipment contributed cost data to the Berkeley Pit cost system files for both operating and repairs during current month, year-to-date and accumulation-to-date time periods. This reporting approach was taken to facilitate analyzing this voluminous data. SUMMARY A Major Component Cost Analysis (Exhibits 6-A thru 6-C) developed by arranging the top ten operating and repair percentages (component cost divided by total cost) in descending order, and then accumulating these percentages to a possible one-hundred percent. While tabulating the operating and repair cost percentages by equipment unit number in the current month, year-to-date and accumulation-to-date time periods, a frequency chart is constructed for each equipment

Jan 1, 1971

More than 1,200 professionals from the global tunneling and underground space industries are expected to be on hand for the 2009 Rapid Excavation and Tunneling Conference to be held at Caesars Palace in Las Vegas, NV. The conference, set for June 14-17, is sponsored by the Society for Mining, Metallurgy, & Exploration, Inc. (SME) and the Construction Institute of the American Society of Civil Engineers. The four-day conference will feature more than 100 technical papers in 19 sessions. Two one-day short courses are also planned, as are a pair of field trips. And the show?s exhibit will feature more than 120 of the industry?s leading equipment and service suppliers.

Jan 1, 2009

By Charles H. Wells

This paper presents a review of the state of the art in coal preparation plant instrumentation and a discussion of automation practice that could be applied based on current mineral beneficiation experience and demonstrated foreign technology in coal washing plants. Specific e-mules of applications of remotely controlled slurry values, pneumatic and electronic field transmitters, computers for control and data logging, and on-line analytical instrumentation are given. A program, to demonstrate this technology is described.

Jan 1, 1980

By M. H. Morcali

Pistachio nut shells, an agricultural waste biomass, and Lewatit TP 214, a commercial sorbent, were investigated as adsorbents for the adsorption of platinum from dilute hexachloroplatinic acid solutions. Before the pistachio nut shells were carbonized, adsorption percentage was 65%, whereas Lewatit TP 214 ensured almost 100% adsorption. However, after the pistachio nut shell was carbonized at 1,000° C under an argon atmosphere, the platinum adsorption (%) increased two-fold. The effects of such parameters as sorbent dosage, contact time, temperature and solution pH on adsorption were studied in detail in batch mode. The adsorption equilibrium data were best fitted with the Langmuir isotherm model. The maximum adsorption capacities, Qmax, at 25° C were found to be 38.31 and 33.22 mg/g for the carbonized pistachio nut shell and Lewatit TP 214, respectively. The adsorption of platinum on both sorbents was found to be described by the pseudo-second-order kinetic model. The results indicated that the activated carbon prepared from pistachio nut shells can be effectively used for the removal of platinum from acidic solutions.

By Tom L. Enos

Increased production through the plant was limited due to thickener circuit constraints. To overcome these constraints and maximize plant throughput to match grinding circuit capability, two options were considered: A. Adding 2000 TPD CIL circuit to operate in parallel with the existing CCD circuit. B. Adding a CIL circuit to treat the entire 4600 TPD while retaining some thickeners for tailings thickening. Option B was selected based on simplified plant operations, reduced operating costs, minimal capital requirements, reduced solution losses, and bullion grade improvement.

Jan 1, 1989