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By David L. Martin

This paper discusses the development of a SLAM II* simulation model with imbedded optimization modules designed M evaluate mineral exploration and exploitation strategies. The model traces through a sequential exploration program, evaluating each deposit site based upon geologic information and potential profitability of the site. At a specified time during the simulation, a new production plan is developed for currently producing deposits which takes into account the planning horizon and deposits which are currently being explored. Potential uses of the model by geologists, engineers, and management decision makers include setting corporate objectives and policies on exploration and production. The model is also useful for testing past decisions to evaluate decision making criteria and evaluating mineral deposit profit potential.

Jan 1, 1983

By C. D. Harrison

This paper presents the results of 18 high-G centrifuge tests performed at the Electric Power Research Institute's Coal Cleaning Test Facility in January 1985. These tests, using -28 mesh (0.6mm) froth flotation product, show that the high-G, solid-bowl centrifuge can produce clean-coal moistures of less than 12 percent at solids recovery rates exceeding 98 percent. The high-G centrifuge achieved these low moistures by applying centrifugal forces up to 2,000 times gravity. Because these forces are two to three times the forces used in a screen-bowl centrifuge, the high-G centrifuge can use a solid bowl and still produce a low-moisture product. The solid bowl captures ultrafines that would pass through a screen bowl, and thus obtains higher recovery rates than a screen-bowl centrifuge.

Jan 1, 1985

By Kumara Rachamalla

North American mining companies are lagging behind their global competitors in participating in the outstanding opportunities in India. The Indian government has liberalized foreign equity participation in the mining sector by up to 50% and, in some cases, even higher. Delegates from Europe, North America and South Africa learned this at an information seminar held in London, England, Attendees were welcomed by L.M. Singhvi, the UK's high commissioner for India. He introduced a government of India delegation headed by B.P. Baishya, minister of steel and mines. Singhvi is an eminent jurist and leading constitutional expert. He reiterated the soundness of India's legal system. He also outlined the recent Investment Protection Treaty between India and the United Kingdom. Baishya emphasized thee geological diversity and strengths of India's domestic market with its population of more than 920 million people the second largest in the world after China and its reservoir of skilled labor. He also outlined the potential of India's untapped natural resources. The private sector is the backbone of the Indian economy. It accounts for 75% of gross domestic product (GDP). The current minimum program of the new United Front government envisions 12% growth in the industrial sector, 7% in GDP and direct foreign investment of US$10 billion a year. "Mining is an area that can attract a sizable part of this investment," Baishya said. "Projected growth of the Indian economy will require increasingly large quantities of basic raw materials, such as coal and base- and precious-metals to meet the needs of domestic and export markets." Administration of India's mining sector is divided into the Ministry or Mines for regulating and developing the country's mineral resources, five public sector Mining Enterprises, the Geological-Survey of India (GSI), the Indian Bureau of Mines (IBM)and 25 states and seven Union Territories. The GSI is the second oldest (founded in 1851) and the third largest organization of its kind in the world, Baishya said. It has geologically mapped more than 90% of India's 3.2 million kmz (1.2 million sq miles) at a scale of 1:50,000. Several promising mineral projects have emerged from regional exploration programs conducted by GSI and the Mines and Geology State Governments. IBM recently completed a national mineral inventory. It covers 13,000 deposits/prospects of 61 nonferrous minerals. GSI also compiled a similar inventory on 61 coal fields. India is attractive to exploration companies for several reasons. These include favorable geology, accessible locations and a large mineral database. India also has many experienced geoscientists with well-equipped and efficient laboratories, Baishya said. Secretary to the Ministry of Mines A.C. Sen emphasized the largely untapped-geological and mining potential of India. He also discussed the new vistas that have opened up opportunities for exploration and mining. India has large quantities of mineral reserves, Sen said. Its vast Precambrian Shield - like those in Canada and Australia - is endowed with gold, platinum group and base metals, as well as coal and industrial minerals. Annual mineral production is valued at more than US$7 billion. Sen pointed out that India is the largest single consumer of gold. And domestic gold prices command at least a 20% premium above international prices. Recent diamond, gold and base-metal discoveries and prospects uncovered by GSI have generated investment interest from abroad, he added Delegates heard that the Indian Constitution gives the central government the job of framing legislation and the regulation and development of minerals. This ensures that mineral laws are uniform throughout the country. However, the right to grant mineral concessions, such as prospecting licenses and mining leases, rests with the minerals' owner. In India's case, that is the state government. The Indian government has formulated several guidelines that regulate the granting of prospecting licenses for large areas. ? The central government will consider the requests of state governments for the granting of prospecting licenses for areas exceeding 25 kmz (9.6 sq miles). But the license must include a provision to conduct aerial prospecting of the area. ? Any prospecting licensing area should not exceed 5,000 kmz (1,930 sq miles). for a single license. And the total area held by one company should not exceed 10,000 km2 (3,861 sq miles) for the whole country. ? The grant of larger areas will be linked to a mini- mum expenditure commitment on physical targets. State governments will monitor these expenditures. ? The granting of large areas for prospecting will be linked to a schedule of relinquishment.

Jan 1, 1997

By Richard Klimpel

The laboratory ball mill grinding of coal/water slurries is described for three coals. Emphasis is placed on the measurement of specific rates of breakage for various operating conditions. Corresponding rheological information is also presented based on data collected using a rotational viscometer. A rheological explanation of the influence of various slurry fluidity conditions on the specific rates of breakage is presented. This rheological approach has proved useful In both the identification of suitable chemicals for increasing breakage rates in coal/mineral slurry grinding and in the plant scale implementation of dense slurry grinding systems.

Jan 1, 1982

By McGuirk. C. H.

The Port of Conneaut, long regarded as a leader in advanced bulk material handling technology, recently incorporated into its existing facility a new, multi-million dollar coal transfer-storage system. While the basic principles of conveyorized bulk material handling remain unchanged in the new system, design modifications such as rotary dumping of railroad cars, automated car feed to dumper, belt rip detection for conveyor belting, bucket wheel continuous production, and other innovations make The Pittsburgh and Conneaut Dock Company's complex worthy of classification as the "Port of Tomorrow - Today". The Pittsburgh & Conneaut Dock Company, the "Port of Tomorrow - Today", 1s a bulk materials storage and transfer facility located on Lake Erie, 68 miles east of Cleveland, 30 miles west of Erie, PA., and 138 miles north of Pittsburgh. Figure 1 shows an aerial view of the facility. It is designed to handle over 25 million tons per year of metallurgical and steam coals, direct shipping ore, fine ores, concentrates, pellets, limestone, and dolomite. Inbound shipments of iron ore and limestone are received from Minnesota, Michigan, Labrador, and Quebec. Coal arrives from Pennsylvania, Ohio, Virginia, West Virginia, and Maryland. Rail service is provided by the Bessemer & Lake Erie Railroad Company.

Jan 1, 1980

By Diana Diaz, Rakshith Shetty, Vitaly Proschenko, Mike Mooney

Cohesive clay soil poses a significant risk to earth pressure balance tunnel boring machines (EPBM) due to unstable face pressure, clogging potential, high cutterhead torque, poor muck flow, low advance rate, etc. This paper details the performance measures desired when EPBM tunneling in clay soil, and the scientifically-supported conditioning methods to transform in-situ clay to a muck with such characteristics, giving particular attention to ground conditions. The paper then examines TBM data from multiple clay soil projects in the context of these performance measures to demonstrate the influence of cohesive soil conditioning on EPBM performance.

Jun 13, 2023

By B. P. Spigarelli

To meet the growing need for CO2 capture and storage technology, Michigan Technological University is researching CO2 capture and storage using carbonate solutions. The objective of the present study was to increase the absorption rate of CO2 into the carbonate solution without reducing the absorption capacity of the solution. This approach used a polypropylene glycol methyl ether (PPGME) as a surfactant to chemically alter the gas bubble size. Experiments were conducted to study the absorption rate of CO2 at varying surfactant concentrations of 0, 0.12, 0.24, 0.36 and 0.48 g/L. Results showed that as the concentration of surfactant increased in solution, the absorption rate also increased. The CO2 absorption rate increased from 3.45 mmol/min CO2 at 0 g/L PPGME to 3.92 mmol/min CO2 at 0.48 g/L PPGME. This amounted to a 14% increase in the CO2 absorption rate with no decrease in absorption capacity of the solution.

"Longwall shearers are widely employed in underground coal mines. The reliability of such machine has significant importance for successful mining operations. This paper aims at studying reliability of a longwall shearer using failure data recorded for a year. Data was pre-processed, sorted and selected for analysis. Selected data is then examined using statistical models. Distribution fitting of time-between-failure (TBF) and time-to-repair (TTR) are accomplished using three different models. Goodness-of-fit criteria is used to ascertain the best fitting model. Reliability in terms of mean-time-between-failure (MTBF), and mean-time-to-repair (MTTR) are calculated using the model which best represents the failure data. Exponential distribution best represents the time between failure and lognormal distribution the time to repair data. A well-known risk management technique Failure Mode Effect and Criticality Analysis is used to evaluate the critical breakdowns. Critical system/parts, experiencing regular failures is delineated based on this analysis. INTRODUCTION Mining is a capital intensive process, and huge monetary investment is required to develop and operate a mining project. Heavy and expensive equipment’s are employed in development and operation of these projects. In order to ensure timely completion of set milestones, it is mandatory that equipment’s perform their required task productively. Delays are not unusual owing to breakdown of these equipment’s. Breakdown or failure experienced by any of the equipment pose heavy financial burden. Moreover, frequent times, companies have to employ and dedicate additional resources to make up for such delays. Delays in project is not only detrimental to company’s image in market, but it also interrupts customer commitments. Mines having history of not fulfilling their promise usually get lower commodity price. Penalties are also imposed on the companies defaulting its obligations. Especially, in today’s world where competition among the companies are growing, success means keeping up the commitments in a timely manner. Heavy machinery and equipment are instrumental in success of any project. These machinery and equipment’s have to reliable in a sense that they can perform the set task in given time period. Reliability of these equipment plays a pivotal role in success of any project. The reliability analysis of mining equipment has long history. Many researchers have applied different statistical models for analyzing the reliability of mining machines (Samanta, Sarkar [1]. Kumar and Klefsjö [2] demonstrated the use of the power law process model for reliability assessments of repairable mining machines. Barabady and Kumar [3] performed the reliability analysis from failure data of the crushing plants."

Jan 1, 2018

By Lorraine B. Burgin

The extensive lead time to develop most Arizona copper deposits commenced with initial production efforts before the turn of the century, when the first attempts were made to recover gold and silver and later copper from the high-grade vein deposits of the territory. Each of these discoveries, prospects, and early operations had its own lead time and life cycle as economic production was attempted. Because prices of the metals fluctuated and the higher grade material was depleted, economics forced operations to close and companies to fail. Renewed interest in the property because of improved conditions, different interpretation of the geologic structure, or new promotional ability frequently resulted in the formation of yet another company to finance the exploration and, hopefully, the development of the property. This cycle of renewed activity and subsequent abandonment was and is common, accounting for many lead times and for the long period of time from the initial location of claims to large-scale production. In order to gain a perspective on the lead-time interval necessary to achieve development of a large-scale operation, the histories of several major Arizona mines were examined, rather than a simple listing of discovery and production dates of many mines to arrive at a statistical average. The Miami, Castle Dome, Copper Cities, San Manuel, and Twin Buttes properties were studied, and as much data as possible obtained on the Pinto Valley, Esperanza, Sierrita, Pima, and Mineral Park-Ithaca Peak properties.

Jan 1, 1974

By Earl Gardiner, Michael Grenier, Stephen Hardcastle, John Vergunst

A prototype, self-contained mine refuge station air supply sys- tem was tested in an underground metal mine to verify it's ability to keep oxygen and catbon dioxide levels at acceptable concentrations in an emergency situation. In this test, 25 volunteers were assembled and sealed in a functional underground refuge station for a period of 24 hours, without the benefit of the standard com- pressed air supply. The prototype system was designed to: 1) operate on a self-contained power supply for a period of at least 27 hours; 2) supply oxygen at a metered rate; and 3) remove car- bon dioxide by re-circulating refuge station air through soda lime scrubbing beds. During the test period, the catbon dioxide concentration remained at an average of 2500ppm and oxygen concentration stayed between 20.2% and 20.6%. The volunteers found the prototype easy to use and seemed confident in its ability to provide a safe atmosphere. The test showed that this technology could become part of an underground mine's refuge station emergency equipment.

Jan 1, 1997

By Benjamin Grunauer, Anthony Iannacchione, Taylor DaCanal

"In Pennsylvania’s rich mining history, various forms of room-and-pillar mining have been in use for over 150 years. Longwall mining, introduced in the late 1960s, occupies only the last 60 of those 150 years and now represents the dominant method of extracting coal in the Pittsburgh coalbed. The introduction of longwall mining allowed larger quantities of coal to be extracted in safer and more efficient manners than room-and-pillar mining. However, the associated formation of subsidence basins have elevated both the number and intensity of watersource and surface structure impacts. When these first longwall panels were mined the factors responsible for these impacts were poorly understood and regulations were focused only on surface structures. Today, with over 600 panels mined under a wide range of conditions, these factors are known and regulations have developed to help mitigate water supply and surface structure impacts.The cause and severity of surface effects are thought to be dependent on multiple factors, including the location within the subsidence basin, overburden, panel width, and orientation of the panel. The changing characteristics of over 600 longwall panels mined in the last 60 years are analyzed to determine factors important in subsidence related surface impacts. This study compares the location of the surface impacts with the longwall panel size, overburden, and maximum predicted vertical subsidence. The data shows that changing these characteristics are impacting surface features in a significant manner as measured by the number of company liable reported effects.INTRODUCTIONLongwall mining has occurred in Pennsylvania for over 60 years, and at the current mining rates, longwall mining is expected to continue in the Pennsylvania Pittsburgh Coalbed until the reserves are exhausted. Figure 1 shows all mining that has occurred in the Pittsburgh Coalbed, as well as the area that is left to mine. It is predicted that there are 40 years left of longwall mining on the Pittsburgh Coalbed, under the assumption that 50% of the total 280,000 acres will be mined at the current rate of 3500 acres/year."

Jan 1, 2019

By T. Tomioka

1. An Overall View of the Japanese Ferroalloys Industry 1) Depressed Demand for Ferroalloys: In Japan consumption of ferroalloys in the last ten years has decreased, although there has been some fluctuation from year to year. During this term production figures of the steel industry, which are closely related to consumption of ferroalloys, are as follows: Shipment of steel products for the domestic market has declined gradually from 69 million tons in 1979, which was the peak year for steel production, to 60.3 million tons in 1982 and 60.4 million tons in 1983, the level of 1978. In addition, exports also have been a downward trend since 1976, which was the peak year with tonnage of 34 million tons, to 28 million tons in 1982 and 31 million tons in 1983.

Jan 1, 1984

By J. A. M. Cano

A brief introduction is made on the existence of sulphides in the top gas of the Midrex Shaft Furnace, giving consideration to the operation of the furnace and the liberation of sulphur as well as its consequential effects on the reduction process. The text shows a study of sulphur distribution in the pellet, emphasizing the importance of this distribution in relation to the liberation of sulphur during the reduction. A study was made to determine the sulphur compounds that exist in the pellets, showing ways of controlling the sulphur distribution and reducing its liberation?during the reduction.

Jan 1, 1989

By R. L. Atwood

The structure, properties, and composition of commercial chelating-type copper extractants are examined. Characterization of these extractants was accomplished using organic separation techniques and analytical tools such as NMR and IR. Results indicate that only the trans isomer of the diphenylhydroxyoxime (LIX (R) 64N) is capable of copper chelation. The effect of the structural modification of the extractants on the extraction and stripping reactions are discussed.

Jan 1, 1972

By R. J. Cornelius

Gold with minor associated copper mineralization in the area of what is now the Bougainville porphyry copper deposit has been known since the 1920s and was probably known in German colonial times, pre- 19 14, although no records persist other than a reference by Stanley (1922) to copper specimens from Kieta that he saw in Rabaul. Stanley did not at the time believe that they came from Kieta. Gold was first discovered at Kupei by Jack Comb in 1929 and the Kieta Goldfield was proclaimed in May 1930. In December 1932, the Tapu Reward Claim at Moroni - the site of the Bougainville Copper concentrator, was pegged by C.W.M. Evans who prospected up river from the West Coast. The Pumkuna (Panguna) Reward Claim on the site of the subsequent porphyry copper deposit was granted in February 1934 to G.A. Myers. n May 193 1, the Kupei Reward Claim was transferred to Bou- gainville Gold Options NL and later reverted to Jack Comb and then the Bougainville Syndicate, as did the Pumkuna and Moroni claims. Most of the interested parties had come from the Edie Creek rush on the New Guinea mainland. In 1935, N.H. Fisher, the geologist in Rabaul for the New Guinea administration who later became director of the Australian Bureau of Mineral Resources in Canberra, reported on the three gold areas. Norm Fisher described the gold and copper mineralization and its habit in great detail and this report had a major influence on the events leading to the discovery in the 1960s. Gold production up to the Japanese invasion probably did not exceed $50,000 in value. Half a ton of copper-gold ore from Kupei was sent to O.T. Lempriere's in Sydney for assay in the early 1930s.

Jan 1, 1991

By T. W. Newell

Small tonnage ore bodies can be developed at a profit on a short life basis. Such is the case of the Bardon Mine in. the Big Indian Mining District in San Juan County. Utah. Faced with a small initial tonnage of high grade uranium ore, the Shattuck Denn Mining Corporation Engineers developed some new ideas for sinking the shaft and planned extraction to warrant the capital risk to mine a limited reserve. The Bardon Mine is located fifty miles southeast of Moab, Utah in the south end of the Big Indian Mining -district. Shattuck Denn Company, a wholly owned subsidiary of the Shattuck Denn Mining Corporation, manages and operates the property under an operating agreement with Kerr-McGee Oil Industries, Inc. of. Oklahoma City. Oklahoma, and Anderson Development Corporation of Albuquerque, New Mexico. Based. on Kerr-McGee drilling., a tabular ore body about 350 feet long by 250 feet wide with an average thickness in excess of seven feet was indicated.- The ore body strikes easterly-westerly and dips from nine to twelve degrees to the south. Uraninite is the dominant uranium ore mineral associated with vanadium. The ore occurs in an arkosic conglomeratic sandstone with some interfingering of mudstone and shale in the Mossback member of the Chinle formation in contact with the underlying Cutler formation. The ore horizon is overlain with 40 to 60 feet of mudstone and shale. Fortunately, the back. immediately over the ore is a reasonable competent shaley sandstone which has made a fairly good. environment for roof bolting.

Jan 1, 1960

By Ken Santini, Ronald R. Bauer, Joseph R. Copeland

Wollastonite, named after W.H. Wollaston, an English chemist and mineralogist, is a calcium metasilicate having the chemical formula CaSiO2. Although it is a unique mineral, wollastonite has a short history of industrial use. Wollastonite is the only naturally occurring, nonmetallic, white acicular mineral. Its acicularity is the main reason for its ascendancy in the late 1970s and 1980s as a reinforcing filler and as a replacement for short-fiber asbestos and short-fiber milled fiberglass. Wollastonite is used in applications ranging from bowling balls to automobile fenders, from ceramic tile to automobile brakes, and from thermal insulation board to protective industrial coatings. The United States is the largest producer of wollastonite, with China, India, and Finland as the other three major sources. The United States, Europe, and the Far East are where most of the production is consumed. Geology Mineralogy and Physical and Chemical Properties Wollastonite, a member of the pyroxenoid mineral group, has the theoretical composition of 48.3% CaO and 51.7% SiO2. Iron, manganese, magnesium, or strontium may substitute for some of the calcium. Commonly associated minerals include garnet, diopside, calcite, quartz, epidote, apatite, and sphene. Some of the physical properties of wollastonite are listed in [Table 1]. Wollastonite is largely chemically inert; however, it can be decomposed in concentrated hydrochloric acid. Some wollastonite will fluoresce under shortwave or longwave ultraviolet light, or both, with colors ranging from pink-orange to yellow-orange and, more rarely, bluish green. In addition, wollastonite may show phos¬phorescence. Because of its unique cleavage properties wollastonite breaks down during crushing and grinding into lath-like or needle-shaped particles of varying acicularity. This particle morphology imparts high strength and is therefore of considerable importance in many of the markets for wollastonite. The acicularity of particles is defined by their length:width, or length:diameter, ratio (i.e., aspect ratio). Individual particles, even the smallest ones, commonly ex¬hibit an aspect ratio of 7:1 or 8:1 and have an average diameter of 3.5 gm. Low aspect ratio products (powder wollastonite, or milled grades) with 3:1 to 5:1 aspect ratios are used as general fillers, in ceramics, and in metallurgical fluxing. High aspect ratio products with ratios of 15:1 to 20:1 are used as functional fillers for rein¬forcing thermoplastic and thermoset polymer compounds and as a replacement for asbestos. The dry brightness and whiteness of wollastonite are also important in determining its suitability for certain filler and ceramic applications. When pure, the mineral is brilliantly white, but impurities may color it cream or gray. Brightness is determined by measuring the reflectance of finely ground powder against a stan¬dard that is assigned a brightness of 100. Magnesium oxide and barium sulfate are the two standards used. G.E. brightness, a term used in North America, refers to brightness measured with a Gen¬eral Electric reflectometer. Commercial wollastonite products usu¬ally have a G.E. brightness ranging from 85 to 95. The Hunter method is also used to measure the brightness of wollastonite. Loss on ignition (LOI), another important property in determining applications for wollastonite, is the amount of volatile matter driven off when the mineral is heated to 1 000°C. Com¬mercial wollastonite products have an ignition loss ranging from 0.5 to 2.0%. Wollastonite's naturally high pH of 9.9 (10% water slurry) is of major importance to its use in the coatings industry. Coatings formulators use milled grades as a pH stabilizer in interior and exterior PVA (polyvinyl acetate) and acrylic latex paints. There are two polymorphs of calcium silicate: wollastonite, a low-temperature form, and pseudowollastonite, a high-temperature form. Conversion of wollastonite to pseudowollastonite occurs at about 1 120°C and results in an increase in the coefficient of expansion and a color change. Pure white wollastonite may change to a cream tint or to various shades of red or brown. This color change is thought to be due to the presence of iron and/or strontium.

Jan 1, 1994

By J. A. Baicker

A 2 1/2 inch diameter probe containing a high resolution gamma ray spectrometer was developed for downhole ore grade assays to depths of 6,000 feet. Tests have been conducted on the characteristics of this tool for in-situ determinations of uranium by means of natural gamma ray counting, and of copper, silver, gold, iron and coal quality by means of neutron-induced gamma rays. Application of the technique for improved carbon-oxygen logging in oil fields is promising. The probe contains a cryogenically cooled high purity germanium detector and a 4,000 channel spectrum analyzer. Gamma ray spectra are digitally transmitted up the cable to the truck-mounted data processing system. We found that uranium can be assayed directly in different types of formations independently of the degree of geochemical disequilibrium by counting the relatively weak 1.001 MeV gamma ray of protactinium-234m. Neutron activation work shows that in-situ determinations of copper, silver, iron and coal quality are technically feasible. In carbon-oxygen oil well logging the technique allows an accurate determination of carbon, oxygen, hydrogen, chlorine, silicon, calcium and iron, and shows promise of providing an improved oil/water differentiator.

Jan 1, 1982

By CHONG WEI, TATYANA KATSAGA, DEREK APEL

This study provides an effective determination process of the interface microstructural parameters in the numerical modeling of the mechanical interaction between two different geomaterials involved with frictional-bonded interfaces, such as the interaction between backfill columns and the surrounding rocks, or the soil-structure interaction, by using the coupled finite-difference and discrete-element (FD-DE) method. The test results validated the feasibility and rationality of the coupled FD-DE method for modeling the combined specimens with frictional-bonded interfaces or joints. Furthermore, this study provides valuable numerical modeling experience for investigating the shear behavior at the interface between cemented backfill columns and surrounding walls by using the coupled FD-DE method.

By Arthur M. Ribe

In my experience, nothing helps me better to get off to a good start in preparing a paper or a talk than a copious consultation with a comprehensive dictionary. I also feel defining the perimeters of a particular subject is helpful to the listener and reader. Sometimes thus precisely defining even the most common of words is helpful. Our general topic this morning as all of you know is "Transportation of Industrial Minerals." The definition of transportation given by the dictionary which I think is appropriate here is: "Systems and modes of conveyance of persons or goods from place to place." Our preceding panelists have outlined for you the state of the art inso¬far as systems and modes of conveyance from place to place are concerned today via rail, water and motor. My assignment is somewhat different as indicated by my topic, "The Traffic Manager in an Industrial Minerals Operation."

Jan 1, 1969