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By Howard W. Wainwright

This bibliography was compiled by the Bureau of Mines as part of an investigation into the possible utilization of low-temperature coal-tar bases. The bibliography consists of literature and patent references from about 1945 to 1961 and is divided into the following headings: Analysis and Composition; Production, Synthesis, Reactions, and Utilization; and Separation, Purification, and Properties. Although over 1,000 references are included, no attempt was made to insure a comprehensive survey. The literature and patent references are arranged alphabetically by author or patentee. When several publications have the same author they are listed in reverse order of age, with the newest first. An author index is included because secondary authors are not cross-indexed. In almost every instance, the entry is accompanied by a Chemical Abstracts reference for those interested in locating an abstract of the original paper.

Jan 1, 1962

By Brian Stump, David Anderson, D. Craig Pearson, Robert Martin

Mining explosions designed to move, bulk or fracture rock are often composed of a number of explosions arranged in a complex spatial and temporal pattern. The effects of the explosions are strongly dependent upon the design and implementation of this blasting pattern. This paper describes the collection, combination and visual display of multiple types of data from these explosions for the purposes of understanding the relationships between the blast design, implementation, and observations. Data sets consist of three-component ground motion, acoustic, video and high speed film, three-dimensional topography, geological and geophysical properties, design blast pattern and timing, and velocity of detonation in the explosive for individual borehole detonation times. The explosions studied include simple single-fired contained explosions, ones designed to bulk and fracture rocks and those that cast material.

Jan 1, 2000

By C. Sawmliana, P. Pal Roy

Near-field blast vibration response of restrained pipelines either buried or exposed was studied during rock excavations at sensitive locations for Stage-II (4x500 MW) commissioning work in a super thermal powerplant of the National Thermal Power Corporation Ltd. (NTPC) of India. The existing running plant of capacity 1000 MW has many important installations including pipelines of varying diameters. These pipelines were very close to the blasting locations (mostly within 12m). Blast optimization and consequent monitoring of vibrations were carried out simultaneously for more than 250 experimental blasts conducted by the authors. This paper emphasized, particularly, on the safety of pipelines and their responses due to repeated blasting impacts. A few guidelines supported by theoretical derivations are provided for futuristic research.

Jan 1, 2001

By L Teixeira, C J. Greet, P Karageorgos

Pyrite is ubiquitous within copper ores, and presents significant challenges to most operations in terms of its impact on copper sulfide concentrate grade and recovery.Samples of ore containing from 3 to 47 percent pyrite, with nominally the same chalcopyrite feed grade, were collected from a copper mine in eastern Australia for testing. The ores were ground under standard conditions using forged steel grinding media in the Magotteaux Mill® to determine the impact of increasing pyrite feed grade on the pulp chemistry of the system and subsequent rougher flotation response. Attempts were made to correlate the pulp chemical parameters (oxygen demand and EDTA extractable metal ions) with flotation behaviour to determine if one (or more) could be used as a metric to infer metallurgical behaviour.The observations made were then tested under different grinding environments (obtained using more electrochemically inert high chromium) grinding media to determine if they hold true.CITATION:Greet, C J, Karageorgos, P and Teixeira, L, 2015. The influence of pyrite on the pulp chemistry and copper flotation response of a chalcopyrite ore, in Proceedings MetPlant 2015, pp 175–187 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By R. Lombard

"Water is a very important component in the production process at underground coal mines. Current unfavourable economic conditions have forced the coal mining industry to identify and address every possible bottleneck preventing optimal production. An increase in water-related downtime was identified as one of the bottlenecks at Goedehoop Colliery’s Vlaklaagte Shaft. The purpose of this project was to identify the various causes that contributed to the high downtime (501 hours in 2013, which led to a potential profit loss of R12.9 million) and to suggest possible solutions.After a thorough investigation the main causes of water-related downtime were identified as low water pressure and low water flow caused by pipe leakages and bursts. The main root cause for the low water flow and pressure was identified as being the low pressure resistance (1600kPa) of the thin-walled galvanized steel pipes used in the underground inbye water reticulation system. The pipes were selected according to the previous 1000 kPa pressure requirement for the continuous miner. However, the pressure requirement changed to 1500 kPa, which resulted in the pipes being exposed to much higher pressures than designed for.The water reticulation system was reviewed and current and future underground pipe layout and water requirements were determined for the shaft. The time frame in which the water consumption would be the highest was determined to be between 1 January 2014 and 7 September2014. Machine and sprayer specifications were used to determine theater consumption at the shaft. Three different solutions were considered to solve the water-related downtime problem and to ensure the efficient supply of water to the newly open sections. Permanent underground concrete dams, semi-mobile dams, or new pipe columns with a higher pressure resistance of 3200 kPa were considered. A trade-off study (taking into consideration cost, time to completion and ease of implementation, maintenance requirements, safety, and flexibility) was completed to determine which of these solutions would be most viable.Paper written on project work carried out in partial fulfilment of B. Eng. (Mining Engineering)"

Jan 1, 2015

By A. Korchevskiy

While Russia continues to be a worldwide leader in asbestos production, the environmental and health status around Russian asbestos mines is not well known and understood, internationally. A literature review was performed to evaluate the potential impact of Russian mining operations on mesothelioma incidence rates in the Ural region where the majority of the asbestos deposits are located. Asbestos that has been mined in this region includes chrysotile, crocidolite, and anthophyllite forms. The Nicholson-Peto (1986) model was applied to published exposure data and mesothelioma mortality statistics in different cities and villages of the Ural region to estimate mesothelioma potency factors (KM) for the various associated fiber types. It was demonstrated that mesothelioma potency factors, as determined by Berman and Crump (2008), could be used to predict mesothelioma risks of non-occupationally exposed individuals in locations where either pure chrysotile, or both crocidolite and chrysotile, are mined and milled. A mesothelioma potency factor was calculated for anthophyllite that appeared to be higher than expected based on previously published studies. The highest incidence of mesothelioma was identified in a community close to a crocidolite mine. The study confirms the validity of utilizing current risk models for non-occupationally exposed populations near asbestos mining activities where asbestos exposures are relatively low and provides methods of characterizing mesothelioma risk in the former Soviet republics (FSRs).

Feb 27, 2013

"WELCOME/BIENVENUE TO THE COM 2014 IN BEAUTIFUL VANCOUVER!On behalf of the organizing committee, I would like to extend my thanks to you for participating in this year’s Conference of Metallurgists. Recent times have been extremely difficult for the resource sector, but it is crucial for our industry to maintain personal connections through good and bad times. These interactions include technical exchanges, and this is at the heart of MetSoc’s service to its members. The theme of this 53rd Conference of Metallurgists is Prosperity Through Process Advancements. There are thirteen symposia at this year’s conference mainly focused on processing from extractive fields, to materials and the environment. Supporting these topics are the plenary, poster session, and trade show plus opportunities for socializing at functions like the opening reception and the awards banquet.Many people have contributed to this conference, from the authors and presenters to the organizers and the generous sponsors. They are all gratefully acknowledged for their quality work over the last two years. A particular thank you to our student volunteers whom we hope will take advantage of their time at COM to network and to learn about this exciting industry.Again, thank you for being a part of this exciting conference of metallurgists. I hope it will be a memorable experience and that you are able to take advantage of all the conference and Vancouver have to offer."

Jan 1, 2014

By Djavid Mohammad

Over the next several years, the storage capacity of the Metropolitan Water Reclamation District of Greater Chicago?s Tunnel and Reservoir Plan will be increased by 14.8 billion gallons through the addition of two large off-line reservoirs: the McCook and Thornton Reservoirs. The Thornton Reservoir will be constructed at the terminus of Calumet TARP System. The constructed TARP system will be connected to the Thornton Reservoir via connecting tunnels and gates systems. The connecting tunnels will comprise of: an upgradient transition tunnel, steel lined bifurcated tunnel for conveyance and control of flow, downdradient transition tunnel, and energy diffuser at tunnel portal. A large, approximately 250-foot-long, 69-foot-wide, and 40-foot-high, rock cavern will be excavated at an average depth of 320 feet to house the bifurcated tunnel system and associated six large control gates, each 12.5-ft by 28-ft wheel gate. Presented in this article are discussions about the TARP system, the Connecting Tunnels and gates Project, regional rock conditions, evaluation of reservoir?s wall stability for evaluation of tunnel penetration, and design challenges facing during design of the: rock cavern hosting the bifurcated tunnel system and gates and associated tunnels and shaft.

Jan 1, 2008

By Raymond J. Castelli

The paper provides a general overview of the numerous types of earth retaining systems currently available, and organizes these various systems by several classification methods. These classifications can be used as a guide in identifying the appropriate type wall or walls for any specific project application. As a further aid in sorting through the numerous wall alternatives for a specific design or construction project application, the paper suggests a systematic approach for wall selection, and presents helpful charts summarizing the general advantages and disadvantages, and typical limitations for the currently available wall systems.

Jan 1, 2003

By Ian Vaz, Takefumi Takuma

"The New Orleans area has been repeatedly flooded by major storms and hurricanes since its French colonial era. After severe flooding in May 1995, the U.S. Congress authorized a massive flood protection project called the Southeast Louisiana Urban Flood Control Program (SELA) in 1996 to improve interior drainage in Orleans, Jefferson, and St. Tammany parishes. However, the project was not fully funded before the landing of Hurricane Katrina in 2005 and Hurricane Rita, which breached many of the area’s levees and flooded 80 percent of the city. Finally, the project was fully funded in 2008 and has been worked on towards its 2017 completion. Another large project simultaneously worked on in the area is the Hurricane and Storm Damage Risk Reduction System (HSDRRS). This system was designed for a 100-year level of flood risk reduction. One particular project within the HSDRRS rendered successful due to an unconventional method of pile driving that was utilized to install sheet piles to reinforce an existing concrete I-wall. This paper will discuss how and why this non-vibratory method of sheet pile installation allowed the project to be successfully completed ahead of schedule.INTRODUCTIONSteel sheet piles were utilized on many of the SELA and HSDRRS projects for permanent cutoff walls under concrete I-walls or T-walls or for temporary earth retaining walls of drainage structures. Although the SELA Project was established in 1996 after severe flooding the year before, hardly any work was done on it until the two catastrophic storms Hurricanes known as Katrina and Rita triggered its revival. These two hurricanes also triggered the HSDRRS soon after the storms’ devastation. The SELA project authorized to improve interior drainage systems while the HSDRRS project was authorized to raise or restore levees and floodwalls mainly along Lake Pontchartrain, the Mississippi River, and Lake Borgne in addition to other areas. Figure 1 shows the SELA Projects that have been completed, are still under construction, or approved for construction. The projects fully highlighted in yellow within the map specified the press-in piling method. These improvements included drainage systems, pump stations, surge walls, and outfall canals as enhanced protection for future storms similar to Hurricane Katrina that caused so much damage by inundating the New Orleans area in August and September 2005 respectively (Facts and Figures, 2012). The completion of these projects were the responsibility of the U.S. Army Corps of Engineers, New Orleans District.Due to the fact that many of the projects were in densely populated areas, the Army Corps of Engineers specified a non-impact, non-vibratory press-in piling method for driving and extracting sheet piles for many of the projects to mitigate noise and vibration impacts. The soft soil conditions in the New Orleans area was also a contributing factor in the Army Corps of Engineers’ decision to specify this piling method due to the risk of settlement for existing historical as well as modern structures. In addition, there were other projects that elected to use the press-in method without any contractual requirements. One of these projects was the Inner Harbor Navigational Canal Reach II Emergency Interim Repair which was part of the HSDRRS project that has been under construction since its authorization in 2005 (Facts and Figures, 2012)."

Jan 1, 2017

Yallourn brown coal and its characteristics have been the subject of innumerable papers and discussions. The Lurgi process adopted for the production of Towns gas by the gasification of brown coal has been described frequently in literature.The application of the Lurgi process for the gasification of Yallourn briquettes has naturally lead to some unexpected problems. Rather than attempt to review the whole field of experience gained in the first two years of operation of the gasification plant at Morwell, this paper attempts to describe two problems encountered, peculiar to the fuel used, and the steps taken in overcoming them.THE PROCESS AND PLANTTo clarify the conditions surrounding the problems, it is necessary to briefly describe the gasification and cooling processes and plant.Brown coal briquettes are gasified in a pressure generator, using a mixture of steam and oxygen as a gasifying medium. Crude gas produced in the generator is washed and cooled in the waste heat boiler and coolers. Figure 1 shows an arrangement of the generator and coolers. The gasifying medium enters the generator through a hollow shaft in the base. This shaft drives the grate, which has three purposes: (a) to distribute the gasifying medium into the fuel bed; (b) to extract the ash from the fuel bed; (c) to support the fuel bed.Briquettes enter the top of the generator through the coal lock chamber and the fuel bed is maintained at a reasonably...

Jan 1, 1960

By Gualberto Salas

Dado que la voladura es una de las operaciones unitarias de mayor extracción del mineral -en tanto logra una adecuada fragmentación de la roca con un costo reducido, es necesario lograr una interrelación entre los resultados de la voladura y el de las operaciones unitarias como herramientas que evalúan y optimizan los diseños de los disparos. En ese sentido, el presente trabajo describe las técnicas para el diseño de las mallas de perforación, los programas para la simulación de la voladura y también para medir los resultados, que permitirán realizar los ajustes necesarios para mejorar los resultados de fragmentación y reducir el costo de operación de minado.

Sep 13, 2001

By Richard Mcivor, Largo Albert

"Inco Limited has operated aluminum mine shaft conveyances since 1968. Aluminum conveyances are used where the hoisting in system requires lightweight conveyances to maintain the hoist rope safety factors and mine hoist rope pulls as dictated by government regulations. Inco Ltd. currently has 20 skips (including spares) operating in the Ontario Division mines. The main problems encountered are with galvanic corrosion between dissimilar metals and metal fatigue. This paper will highlight some of the problems encountered and illustrate methods utilized to overcome the problems and improve the conveyances performance.IntroductionAluminum mine shaft conveyances have been in use at Inco Limited's various Sudbury district mines since 1968. All of the conveyances currently in use are skips used for hoisting mine ore and rock. Inco had an aluminum quick change Kimberley-type skip and cage in operation at its Totten Mine in the early 1970s, but this mine is no longer in operation and no further comment will be made.The primary reason why aluminum conveyances are chosen over conventional steel conveyances is because of their light weight. Typically an aluminum conveyance will weigh about 60% to 70% of a steel conveyance of similar design. The lighter weight conveyances will allow higher payloads to be used and still maintain the statutory hoist rope factors of safety. It must be remembered that increasing the payload will increase the power required to raise the load and the hoist will have to have the necessary horsepower for the increased payload or the system will be overloaded.The front dump (Rola-chute) skips are of the bail-less design, i.e. the box structure also supports the load and has the shaft guide shoes attached directly to the side of the box structure. The Copper Cliff North Mine and South Mine skips have a joint in the centre of the conveyance and are installed in the shaft in two sections and connected with pins. This feature allows very long (42 ft) skips to be used in areas where a one-piece bail-type conveyance could not be installed. It is not practical to make sectionalized bail-type conveyances"

Jan 1, 1988

When defining a ?megaproject,? one need only to look at Seattle, WA?s State Route 99 Alaskan Way Viaduct replacement project. This $3.1-billion project is one of the largest of its kind in the world, and includes the use of the world?s largest tunnel boring machine (TBM). However, for as large as the Alaskan Way project is ? especially given the size of the TBM being used ? there are several other megaprojects underway around the world. Each has its own challenges that require innovative design techniques and financing arrangements, as well as variations on established tunneling technologies. So it was that 266 tunneling and underground construction professionals ? owners, contractors and engineers ? convened in Seattle in November for the Cutting Edge Conference on Megaprojects. This was the second joint meeting between the Underground Construction Association of SME and the North American Tunneling Journal. The first joint conference took place in April 2012 in Miami, FL and attracted 238 attendees. A third joint conference, to be held in 2014, is in the planning stage. The key reason Seattle was chosen as the site of the megaprojects conference is the Alaskan Way Viaduct project. Before the conference began, many of the attendees were able to visit the project and get a close look at Bertha, the Hitachi Zosen earth pressure balance TBM that is boring the tunnel. In addition, the conference included an exhibit that attracted 20 industry suppliers, up from 10 the previous year in Miami. The 25 presentations during the two-day conference covered all aspects of the tunneling and underground construction of megaprojects. Topics included the Alaskan Way Viaduct project; considerations for procurement and contracting; political risk, financing and insurance; international megaprojects; risk and risk sharing and project delivery. Each session concluded with panel discussions.

Dec 1, 2013

By Gunter Swoboda, Harald Wagner

Until a few years ago tunnel construction was based exclusively on experience. In recent years, however, numerical models have increasingly become an integrated part of tunnel design [2]. These models permit good evaluation of the tunnel's support behavior even before it is designed. In particular, numerical methods are highly suited for the development of new construction methods. The prerequisite for this is the application of high-performance pre- and postprocessors, permitting the design engineer to come to a quick interpretation of the analysis results. In future, 3D analysis will take on increasing significance, for which reason this paper also deals with this type of models.

Jan 1, 1993

By L C. Pretorius

Pipe pigging is a technique for the in situ (field) coating application, to create a seamless internal anti-corrosive lining of long pipelines. The technology originated in the cleaning of pipes, and these proven cleaning methods continue to be used today. Firstly mechanical cleaning of the pipeline is performed, using wire brush, razor back, course stud and fine wire pigs, then foam pigs, or criss cross pigs, and urethane blade scrapers to remove loose debris, wax, residual hydrocarbons and corrosion products from the pipeline. Part of the proprietary techniques and expertise is to ensure that these cleaning pigs do not get stuck Next chemical cleaning of the pipeline is performed, using repeated pig runs with detergents, solvents, acid etching, corrosion inhibitors, consecutively batched between two pigs, to ensure a clean, dry metal finish to a visual cleanliness standard of ISO SA2½. These in situ techniques were developed, 40 years ago to apply internal corrosion protection to pipes using a thin layer of epoxy based paint (50 to 100 micron). Until recently these old techniques were never improved upon. Although many thousands of kilometres of pipes were successfully coated with these thin film epoxy based paints and old application techniques, these thin paint films had problems in weld coverage, and were also unable to fill pits caused by pitting corrosion, and unable to replace metal loss caused by channel erosion. New coating material developments, revised application methods and modified pigging equipment have now made it possible to apply thick film coatings as corrosion barriers to the internals of pipes in the field, using these pigging techniques. The thick coating films can be up to 1 mm (40 mils) thick in a single coating run over long distances. The new thick film coating materials and application techniques are similar to continuous screeding, creating a far more robust seamless internal pipe lining when compared to the old technology of thin film paints. With thick film polymers the option now exists to create a structural GRP pipe within a pipe, be it steel or cementicious. It has been preferable, even necessary, to move away from the traditional epoxy paints and coatings. It was found difficult or impossible to use epoxy materials for these pipe coating applications due to the requirement for achieving a suitable viscosity with adequate hold up. In order to reduce epoxy viscosity a solvent or reactive diluent is required. This inevitably lead to solvent entrapment and poor cure characteristics in cold climates. Further mud cracking in over thick areas, the inability to extend or reduce pot life, poor control of cure time and limited resistance to aggressive or chemical environments made solvent based epoxy resins a poor choice.

Jan 1, 2006

By A. A. El-Midany

Traditionally, the choice amongst different upgrading techniques or in finding the optimum operating conditions for a given upgrading technology depends on whether one is looking at the grade or the recovery of the valuable mineral in the concentrate. In fact, the conclusions are not usually the same. This is because the best technique or optimum operating conditions for the highest grade are not the same as the conditions to achieve the maxi-mum recovery. Therefore, a unique measure that takes into consideration both grade and recovery is urgently needed. Finding such a measure is the objective of this paper. A proposed measure provides a selectivity index in the range of 0 to 1, where 0 is no selectivity and 1 is ideal selectivity. The index can be obtained by plotting the so-called Fuerstenau upgrading curve, which relates the recoveries of the components in products of separation and a running regression applying a one-parameter equation. The measure was applied to assess the selectivity of selective flocculation under different operating conditions when used as a sensitive upgrading technique for ultrafine ground ores. After applying the proposed selectivity measure in the case of the selective flocculation of ultrafine Egyptian iron ore without the addition of cations, it was found that the optimum conditions are pH 11, 1 kg/t sodium silicate and 0.4 kg/t potato starch with a selectivity index of 0.55. With the addition of cations, the optimum conditions were found to be pH 11, 1 kg/t sodium silicate and 2 kg/t potato starch with a selectivity index of 0.65. It should be noted that determining these optimum conditions using the traditional grade or recovery measures was highly ambiguous.

Jan 1, 2008

By Takuya Taguchi, Toshihiro Ogata, Atsuio Inoue, Shigeyuki Sasaki

Highly improved drilling machines and mucking machines have been used for the underground construction. To have rapid construction, the roles of blasting operation ha ve been growing more important. At the most tunneling of present, cartridged emulsion explosives have been used for a blasting in Japan. Under this circumstance, a blasting system of ANFO explosives using loading machine has been used recently for a tunnel blasting. However, ANFO has some problems, such as a useless explosives in wet boreholes, bad blasting fumes and the ammonia gas due to the decomposition of ammonium nitrate in contact with the sprayed concrete in tunnel.

Jan 1, 2005

By D. Turnbull, H. N. Treaftis

Precipitation of tin from Pb-Sn alloys (lead-rich) occurs by the nucleation and growth of hemispherical cells which consist of tin lomelloe interspersed in the depleted solid solution. Nucleation and growth of these cells and the tin interlamellar spacing at various compositions and temperatures have been investigated. The interlamellar spacing increases approximately as the reciprocal of the logarithm of the supersaturation ratio. For constant initial tin concentration the concentration of cell nuclei increases with decreasing temperature to a limiting temperature-independent value. The kinetic results support the view that the cell growth rote is governed by the diffusion of tin along the cell boundary. In the main, the results confirm the authors' earlier deductions, drawn from resistometric and calorimetric data, about the precipitation mechonism. IT has been shown1, 2 that tin (ß) precipitates from lead-rich (a) PbSn solutions by the nucleation and growth of cells (cellular or discontinuous precipitation). These cells consist of tin lamellae, with a spacing 1, interspersed in a depleted a solution. Reorientation of a also accompanies cell growth. The kinetics of cellular precipitation of tin from lead have been measured by resistometric2, 3 and ca1orimetric1, 3 techniques. The time-transformation isotherms (t equals time; x, volume fraction of specimen transformed) of the initial rapid precipitation, which drains about 60 pet of the tin from solution, have been described by a kinetic law having the form x = 1 —exp (—bt n) [I] where n usually has the value 3.0. It was shown" that this law and the other kinetic facts can be explained satisfactorily if it is assumed that the cells grow at a constant rate and that all the cells nucleate in a time negligible in comparison with the period of cell growth before impingement. Thus, for hemispherical cells b = (2/3)pNG3 [21 where G is the rate of cell growth in cm per sec, and N is the number of cell nuclei per unit volume. The rapid rate of cell growth at low temperatures can be accounted for"' if it is assumed that the dissolved tin drains to the lamellae edges by diffusion along the sweeping cell boundary rather than by diffusion through the a crystal (volume diffusion). For cell growth governed by cell boundary diffusion it was shown, approximately G=2(X° - X° / X° ) DBA / l2 where A equals the thickness of the cell boundary; D R, the coefficient of diffusion of tin atoms within the boundary; and X° and X, are the atom fractions of tin in the supersaturated and saturated solutions, respectively. Zener8 had already shown that, where

Jan 1, 1959

By W. A. Tiller, J. D. Harrison

HOT pressing of powder particles has gained importance recently, since it affords a method in which high densities are rapidly attained. In a recent study on hot pressing of alumina powders, Mangsen, Lam-bertson, and Best1 have shown within the limits of their experiment, the validity the rate equation for densification in hot pressing, originally proposed by Murray, Livey, and Williams.2 i.e., where D = fraction of theoretical density, t = time, P = pressure and 77 is the viscosity, all in appropriate units. This equation was derived from earlier work of Shuttleworth and Mackenzie3 which is based on the closing of spherical pores under the action of surface tension. The integrated form of this equation yields a straight-line relation between log (1 - D) and t. Such conditions were found by Felten4 to be true only after extended periods of pressing. In an endeavor to quantitatively evaluate the exactitude of this equation in the initial sintering stage, i.e., prior to sealing of the pores, spherical anti-

Jan 1, 1962