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By Christopher J. Pacitto

This paper presents a case history of an engineered, monitored, and tested program that provided an effective and satisfactory basis for the completion of pile foundations for Twin Dolphins 1 at La Peninsula Condominiums located in the Isles of Capri in southwest Florida, U.S.A. An 8-story building (withl-story parking underneath) along with recreational facilities (such as a swimming pool and tennis courts) had been planned for final construction. Following an evaluation of various foundation alternatives, a precast prestressed concrete (PPC) pile-supported system was selected. The building foundations were designed for pile capacities of 445kN (50 tons) and 890kN (100 tons) in compression and 133kN (15 tons) in uplift. A test pile program was performed to provide site-specific pile driving data, verify design assumptions, determine production pile lengths, and evaluate pile driving criteria. A total of 24, 356 mm (14-in.) square, 19.8 m (65 ft) PPC concrete piles were driven and dynamically load tested utilizing a Pile Driving Analyzer (PDA) within the building limits. Dynamic monitoring during probe pile installation and restriking was performed to estimate the ultimate capacity of the piles and to evaluate driving stresses during installation. CAPWAP analyses were preformed on PDA data to better estimate pile capacity, resistance distribution, and predict pile freeze (increase in pile resistance with time) and thus optimized the production pile lengths. Upon completion of probe pile installation, 12 of the probe piles were tested using the Pile Echo Tester (PET) function of the Pile Integrity Sonic Analyzer (PISA). PET testing was performed to evaluate the integrity of piles which had exhibited high driving stresses during PDA testing. Information gathered during the probe pile driving program was effectively utilized as part of the overall quality control program to install a total of 539 PPC piles (including 24 probe piles) within the building limits at the project site to depths ranging from 9.1 to 19.8 m (30 to 65 ft) below the existing ground elevation as part of the foundation support system. Prior to installation of probe or production piles, a termination criterion was established using 1-dimensional wave equation analyses in addition to the design pile embedment requirement. The predicted pile capacities compared very well with the capacities from the CAPWAP analysis for probe piles. Use of geotechnical instrumentation and PDA assisted technology enabled each foundation support element to be constructed to its optimum capacity and at optimum cost. Furthermore, by using PDA the consultant was able to quantify a difficult to measure geotechnical phenomenon termed "pile freeze" which eliminated costly overdriving and unnecessary splicing of piles.

Jan 1, 2002

By Christian Flores

El proceso que se enfrentó en Tambomayo tuvo su principal complejidad en llevar un proyecto en etapa de exploración hacia la construcción de una a unidad productiva la cual permita obtener resultados económicos y trabajar con altos estándares operacionales en el que prime la seguridad y un buen clima laboral, acompañado al hecho de que la empresa cuenta con una cultura operativa tradicional, lo que género que las principales dificultades para la toma de decisiones es que se tengan que ir derrumbando paradigmas operacionales y de esta manera ser un agente de cambio para el logro de los objetivos.

Sep 1, 2017

By C. A. Pickles, J. M. Toguri

The refining of two molten Ag-Cu alloys, containing 7.5 and 11.2 mass% Cu, with a borosilicate slag was investigated using both air and pure O2 to determine the effects of the following variables: flow rate of oxidising gas; injection time; mass of sodium borosilicate flux; and injection of the oxidising gas into either the slag or the metal. The results demonstrate that more than 90% of the Cu can be removed with Ag losses of less than 5% and that refined metal with a Cu content of less than 0.5 mass% can be produced. Ag losses to the slag increased with the amount of Cu removed, and a mechanism is proposed to account for this

Dec 1, 1995

By BUREAU OF MINES

This report is submitted in accordance with the provisions or une Synthetic Liquid Fuels Act of April 5, 1944 (30 U.S.C. 321-325, as amended), which require that: "The Secretary of the Interior shall render to Congress on or before the first day of January of each year a report on all operations under this Act." Owing to the broad scope of the content and the diversity of interests represented, the Annual Report for 1951 has been divided into two separate publications. Each has been published by the Bureau of Mines as a Report of Investigations, and the respective titles follow: Oil from Coal. R. I. 4865, Part I - R. I. 4866, Part II - Oil from Oil Shale. Identical in each report, the introduction summarizes research progress made in 1951 under the entire Synthetic Liquid Fuels program. A free copy of these publications may be obtained by a written request to the Bureau of Mines, Publications Distribution Section, 4800 Forbes Street, Pittsburgh 13, Pa. The R. I. number and title of the publication desired should be indicated.

Jul 1, 1952

By William R. Yernberg

The 26th Peruvian Mining Convention (Convención de Ingeneieros de Minas del Perú) was held Sept. 15 through 19, 2003, in Arequipa. The convention was sponsored by the Peruvian Institute of Mining Engineers (Instituto de Ingeneiros de Minas del Peru). The Institute has been organizing these events since 1954. They are now held every other year. The conventions spotlight Peru’s mineral resources and have contributed to the tremendous growth of the Peruvian mining industry. This year’s meeting consisted of technical sessions, forums, field trips and social activities. It was held at the Tecsup Institute of Technology of Arequipa. More than 3,000 mining professionals attended. As always, the meeting was well organized, and participants expressed gratitude to the organizing committee for another successful meeting.

Jan 1, 2004

By Andy Schroeder

Located in Hamilton, Ontario Canada, Berminghammer Foundation Equipment, is a manufacturer of advanced foundation equipment with 30 years of experience. The company is represented in more than 20 countries world wide, maintains an extensive Research and Development team, and has earned a reputation for finding the most practical solutions to the most challenging projects. The vertical travel lead, referred to as "VTL" system, was first developed and patented by C.W. Bermingham in the 1970's. This lead system was developed in response to the fundamental limitations of either a fixed lead or hanging lead system. The fixed lead system is well suited to level job sites with few obstructions and has the advantage of faster positioning of the lead, the hanging lead is very adaptable to different elevations and batter piles but takes much longer to position. Therefore the Vertical Travel Lead was developed to combine the advantages of fixed leads, fast and accurate positioning, with the ability to adjust the height of the lead base up or down. The VTL lead is connected to the boom by a sliding connection which allows the lead to be elevated or lowered below grade. The advantages of the VTL system were recognized by many foundation specialists and they have become the Industry standard in Canada , US Railway Construction , and many parts of the USA.

Jan 1, 1997

By Nobuzwe Makhotla, Sasha Boskovic, Steve Hearn

"Mineral separation efficiency in flotation depends, to an extent, on the type of frother used. Huntsman develops and manufactures unique frothers which are suited for mineral processing applications. This paper discusses the Huntsman approach to understanding the industry’s flotation frother requirements to optimise frother selection and introduce the Huntsman’s POLYFROTH® frother range. Specific case studies where the frothers are used are discussed. INTRODUCTION Froth flotation is a process of using bubbles to separate minerals based on their relative affinity for water. Bubbles are induced in the slurry through aeration. Chemistry is used to aid the flotation process and chemical reagents are added to enhance the separation process. The flotation reagents include frothers, collectors, surface modifiers and pH regulators that control physical and chemical conditions of solid, air and liquid phases, respectively. As described by Harris (1976), the key effect is that of bubble size control by way of preservation of the generated bubble size, which is attributed to the coalescence inhibition by the presence of the frother on the bubble surface. Following this, the frother must stabilize the froth phase. Frothers are also added to create optimal conditions for bubble creation and stability by decreasing the surface tension of the water. Depressants may be added, depending on the ore treated, to assist the hydrophilic particles to stay in the water phase. Clay particles may need to be dispersed to prevent them from attaching to the bubbles. Hydrophobic particles attach to the bubbles and are carried to the surface of the slurry where froth is formed. It is important for these bubbles to have the mobility to carry the mineral to the launder where the concentrate is collected. Types of Frothers There are generally three main groups of frothers used in froth flotation. Alcohol Type These frothers have a molecular structure that usually includes 5 to 8 carbon atoms in a hydrocarbon chain and their solubility in water is limited. Methyl isobutyl carbinol (MIBC) belongs to this category and is widely used in the industry. The weaker alcohol-type frothers are more selective and typically suited to finer particles. There are three sub-categories under this group: aliphatic, cyclic and aromatic alcohols."

Jan 1, 2015

The development of Western Mining Corporation's first commercial gold heap leaching operation is described. The laboratory testwork requirements for determining the amenability of ore to heap leaching techniques is discussed. Heap construction and operating practices are described; and production statistics and operating parameters are presented. It is shown that for a specific low grade gold ore a treatment cost optimization can be performed. Taking cognizance of the ore grade, percentage gold recovery, operating costs, and the gold sale price, it can be determined whether Carbon-In-Pulp (C-I-P) or Heap Leaching should be employed as the extraction process. The examples presented in this paper refer specifically to Kambalda and should not be used in themselves as generalities.

Jan 1, 1987

By C Adams

Reports of delays and cost blowouts in major study and construction projects are becoming increasingly prevalent in the resources industry. This is mainly being attributed to an escalating cost environment associated with the increased number of projects in the development to construction pipeline and a scarcity of competent skilled resources to deliver these projects. However, not all this effect can be directly attributed to the current environment. Historically the mining industry has not performed well in its ability to deliver projects according to the financial and physical parameters forecast in the feasibility study process. To manage the risks associated with delivery of major projects, resource companies need to ensure they use a standardised approach to management of their project development to satisfy project objectives and enable more efficient use of the increasingly limited available resources. Each discrete step in advancing the project from scoping study to operations needs to be integrated, reducing the amount of rework and duplication. This paper is primarily a consolidation of existing ideas on project management systems but also introduces new concepts to solve current issues. It describes the basic components of a typical mining project, the issues that commonly arise, the key attributes, and critical steps required for an effective integrated project management system covering projects from initial scoping studies through to project commissioning and operation. This paper focuses on technical study components of the mine development project with allowance for transitioning to design and construction and operation phases.

Jan 1, 2006

By Sara Jane Boles

In recent years the interest in rare-earth compounds as refractory materials has exceeded the available literature on the subject. While some basic properties, such as density and melting point, of the more readily available rare-earth compounds have been reported in the literature, relatively few papers can be found that deal comprehensively and primarily with high-temperature refractory properties and applications of rare-earth oxides, carbides, sulfides, and nitrides. Therefore, this bibliography has been pre-pared for the use of the ceramic industry as a guide for locating and utilizing the scattered and frequently fragmentary information available. The term "rare earths", as applied in the literature search for this bibliography, is understood to include the following elements: cerium, dysprosium, erbium, europium, gadolinium, holmium, lanthanum, lutetium, neodymium, praseodymium, samarium, terbium, thorium, thulium, uranium, and ytterbium. (On the periodic chart, these elements appear as numbers 57 through 60, 62 through 71, 90, and 92.) It is emphasized that many of the abstracts included are from papers in which the rare-earth compound or compounds are treated along with several other ceramic materials, are mentioned only secondarily, with primary interest placed on a more commonly used refractory material, or are used as part of a mixture of materials formed experimentally and reported on in the paper. As the better known rare-earth materials, such as the oxides of uranium, thorium, and cerium, appear more frequently in the literature, they also appear more frequently in this collection. Articles abstracted include only information on the basic properties that are of interest to the refractories investigator. References to crystal lattices and related topics are generally excluded from this publication. The temperature 1,500° C. has been set arbitrarily as the lower limit for reported data on thermal properties. However, because of the scarcity of information, some reports are included in which data are limited to those obtained at lower temperatures. Many of the articles abstracted include lists of references that will be of additional assistance in pursuing specific lines of investigation.

Jan 1, 1962

By T. M. Barczak, S. C. Tadolini

Pumpable roof supports provide an alternative approach to secondary support in underground mining. Unlike all other supports that are either partially or fully prefabricated prior to being transported into the mine, the pumpable support is fabricated in place in the mine entry. This reduces the underground material handling efforts and thus the injuries historically associated with in-mine support construction. On-site fabrication also facilitates application of the support in areas that are inaccessible to transportation equipment such as scoops or rail cars, making it ideal for many bleeder applications. One of the main advantages of the pumpable support is that it fully bridges from the mine floor to the roof, thereby eliminating the requirement of “topping off” the support with wooden wedges or crib blocks that soften most other support responses. This report examines the development of modern pumpable roof support technology and provides a full description of the performance capabilities of each of the support products now on the market.

Study on the New Flow Sheet and Wastewater Recycling for Xiaoliuguo Copper-Bearing Low-Grade Scheelite Ore

Sep 13, 2010

By R. E. Moore

Refractories are unique ceramic materials, which are used in large quantities in steel making furnaces, metal smelting vessels, and glass melting tanks. They are required to possess high thermal shock properties and good slag corrosion resistance as well as creep resistance at high temperatures. Therefore, they are made from very refractory minerals such as lime, periclase, corundum, spinel, and zirconia. Slags are vitreous materials produced as a residue in steel refining processes. They cover a wide range of compositions and may contain pure oxides, silicates, and sulfides as well as fluoride phases depending on the melting and smelting processes. These minerals exhibit spectacular cathodoluminescence color under electron bombardment; therefore, cathodoluminescence (CL) microscopy is found to be a superior technique for the characterization of refractory corrosion by slags. Examples included in this study are (1) reaction of fluorine containing mold slags with ZrO2-C nozzle refractories promoting crystallization of the Cuspidine, Ca4Si2O7(F,OH)2, (2) corrosion of fusion cast refractories in TV panel glassmaking furnaces and formation of glass defects, and (3) reaction of spinel based castable refractories with copper smelting slags.

Jan 1, 2001

By M. A. Trevits, M. R. Thibou, A. Ozment, A. C. Smith, J. B. Walsh

The Excel No. 3 Mine is a room-and-pillar mining operation owned by MC Mining, LLC, a subsidiary of Alliance Resource Partners, LP, which produces coal from the Pond Creek Coalbed in Pike County, Kentucky. Late on December 25, 2004, a fire was discovered near the bottom of the slope and, after an unsuccessful attempt to fight the fire underground, it was decided to address the fire remotely from the surface. The mine operator developed a plan to fight the fire that called for the installation of temporary seals at the slope and mine shafts to eliminate the inflow of oxygen. In addition, the plan called for drilling and completion of vertical boreholes into select areas of the mine workings to monitor the mine atmosphere and inject nitrogen gas and gas-enhanced foam. Over the next 9 days, nitrogen gas was injected almost continuously and gas-enhanced foam was injected periodically as deemed necessary. On January 7, 2005 it was determined that the fire was successfully suppressed. This paper presents a discussion of the fire-fighting approach and an analysis of the results of the application of gas-enhanced foam technology.

Development of Technology for Complex Uranium Ores Processing on the Flotation Process Basis

Sep 13, 2010

By K. Richardson

Although the De Beers group has a long history of placer mining on land, the group only became actively involved in deep water marine diamond exploration and mining in 1983 with the formation of DeBeers Marine. Full-scale commercial mining commenced around1991. Since then, the group marine mining capability has grown into a formidable fleet of 8 large deep water (>70 m) mining vessels, as well as other special purpose geosurvey platforms. Marine diamond production by the group is expected to be just short of 1 million carats in 2006. De Beers operates across the entire value-chain spectrum from geology and geosurvey, through sampling to mining, and finally ore processing into high value concentrate. Supporting these operations involves significant service activities such as maintenance, security, logistics and environmental management. Specific challenges exist in terms of developing or acquiring appropriate technology for marine mining. These challenges have resulted in De Beers operating extensive in-house R&D and projects departments, as well as drawing extensively from technology partners. An array of computational and test facilities is also available to support R&D and projects activities. Hydrotransport in various guises is key to the current approaches to marine mining and ore processing. Use is made of airlift and centrifugal pumping for hydraulic hoisting of very coarse gravel, while splitters, launders, dewatering, elutriators, jet pumps, centrifugal pumps, dense medium circuits, pipeline systems, and instrumentation for coarse abrasive particles are used extensively in the ore processing plant.

Jan 1, 2007

By Arthur C. McFarlan

There are two distinct coal fields in Kentucky-the Eastern field constituting a part of the Appalachian coal region and the Western field constituting the southern part of the Eastern Interior region. The outcrop pattern of the State is dominated by the Cincinnati arch. Coal-bearing Pennsylvanian strata occupy a low structural position on either flank, preserved thereby from erosion, which in the past has removed these same beds, though a much thinner succession, from the crest of the arch. General geological relationships are shown in figures 1 and 2. On April 13, 1750, Dr. Thomas Walker discovered the first coal recorded in Kentucky. He entered the State through Cumberland Gap (Cave Gap) and found coal a few miles north.

Jan 1, 1944

Disseminated gold mineralization in the Vunda River area 12 km SE of Lautoka in Viti Levu occurs sporadically in shoshonite volcanics within an alteration area of some 6 km2. No definite intrusions have yet been located though possible intrusions occur toward the centre and on the eastern margin of the area. The nature and distribution of alteration suggests the presence of a co-magmatic mineralizing stock just below the surface.The gold occurs within close spaced fractures and occasionally around the c1asts of breccia and agglomerate.Various types of alteration compatible with porphyry mineralization occur, but to date show no zoning or defined correlation with incidence of gold which occurs in various alteration facies.It is suggested that the gold and trace copper mineralization at Vunda arises from the sub-volcanic intrusive phase (monzonite) of the Sambeto shoshonite (5 m.y.) and is part of an E-W zone of porphyry-type mineralizationtrending easterly to the Kingston porphyry copper deposit at Navilawa.There is a close similarity between the Vunda mineralization and some of the porphyry deposits of alkali affinity in British Columbia, Canada.

Jan 1, 1978

This paper provides an update to a paper by the author on an overseas explorer's perception of New Zealand, presented at the 1997 New Zealand Minerals & Mining Conference. New Zealand has one of the most open and internationally competitive economies in the world. The petroleum exploration industry in New Zealand is booming with a record number of wells planned for 2000. New Zealand is keen to encourage investment in mineral exploration to develop its natural resources. A study of the geological potential of New Zealand estimated the value of known and potential resources of metals at $86 billion. Gold has the greatest potential, with a total resource estimated at $33.5 billion. The price of gold has averaged NZ$554 since the beginning of 1998, and NZ$593 in the last year, which is very competitive with other countries. An assessment of country risk compared New Zealand with twenty other countries in ten risk categories: sovereign risk, land access, environmental issues, land claims, mining legislation, social risk, infrastructure, civil unrest, natural disasters and workforce. New Zealand ranked fifth, showing it has low country risk. This provides a high degree of certainty for investment, which is important for the perception of New Zealand as an exploration destination. Corruption was considered separately, and New Zealand ranked third out of ninety countries, showing it is one of the least corrupt countries in the world. New Zealand has a favourable business environment, good geological potential, low country risk and no corruption. Despite this, New Zealand has not registered on the radar screens of overseas mineral explorers, and the positive factors appear to have been overlooked. New Zealand has considerable undeveloped mineral potential, and with the current rise in commodity prices, it is hoped New Zealand can participate in a resurgence in mineral exploration.

Jan 1, 2000

Ecological Fuel from High-Sulfur-Content Coal

Sep 13, 2010