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By J. E. Davidsen, M. Honstad

"A well-maintained tap-hole channel is important in order to achieve good and stable furnace operation over time. A worn or short tap-hole channel can lead to more violent flow, significantly increasing the fume emissions during tapping and leading to more metal being mixed with and lost to the slag. Over time, a worn tapping channel might cause side channels and damage to the lining around the tap-hole area. This can result in a burn-through which is a considerable safety risk and will cause significant production losses. At Eramet Norway Porsgrunn, tap-hole maintenance has been done regularly with electrode paste for over three decades with good results. This article summarizes some of the experiences obtained from this practice on a 33 MW SiMn furnace, as well as a change to a coal tar pitch-free binder. IntroductionA well-maintained tap-hole channel is important in order to achieve good and stable furnace operation over time. Metal and slag are regularly tapped from the furnace and may cause a lot of wear on the tapping channel, increasing the risk of lining damage and ultimately leading to a burn-through. On furnace 10 at Eramet Norway Porsgrunn, the tap-hole area is the part of the lining that has been by far the most prone to burn-through since the startup of the furnace.Experience shows that almost all lining problems have started with burn-through in the tap-hole area or in close proximity to the tap-hole. During tap-hole repairs, side channels with metal and slag have also been observed emanating from the main tapping channel. In addition, a shorter tapping channel will cause more violent flow. This can lead to more metal droplets being entrained in the slag, and increase the risk of the furnace not being closed properly at the end of the tap.As a burn-through is a considerable safety risk, and also causes significant production losses, systematic work has been performed over the years to maintain the tapping channel in order to prevent burn-through."

Jun 1, 2019

By R. MacRosty, R. Pula, P. Gebski, W. Braun

"This paper provides a progress update on three tapblock monitoring technologies that Hatch has been developing with our clients for non-ferrous smelting furnaces.The Tapblock Diagnostic System (TDS) is an advanced on-line monitoring system that uses temperature data along with embedded thermal model results to evaluate the condition of a tapblock over its campaign life. Hatch recently installed a second Tapblock Diagnostic System, some details of which are provided in this paper.The Tap-hole Acoustic Monitoring (TAM) system is installed on water-cooled copper tapblocks and uses the noise from the tapping channel to provide a qualitative indication of wear and deterioration of the tapping channel refractory. In addition, TAM can be used to monitor drilling and lancing performance, and potentially could also be used in the future as a guide for automatic drilling and lancing systems (Sadri et al., 2008).The third technology is the use of fibre optic sensors to measure temperature on the hot face and in the tapping channel of a tapblock. Fibre optic technology allows installation of numerous sensors in key locations where they are very sensitive to tapblock condition and also provide more extensive spatial coverage than is possible with traditional instruments. This paper provides an update on our efforts to address issues with premature failure of the sensor cables due to corrosion, and also converting the vast amount of data from the sensor cable into information that can be used by furnace operators."

Jan 1, 2014

By S. Botes, H. van der Merwe

While the refractory lining contains the process on a steady-state basis, the tap-hole must provide a channel for transport of molten materials at discreet intervals, with thermal cycling as routine. The tap-hole introduces a discontinuity in any lining, and this fact can lead to failure in the region around the tap-hole before general lining failure occurs. Hence there is a need for a rapid and reliable tap-hole repair technique that can be readily implemented in conjunction with all types of linings. The UCAR®V Repair supplied by GrafTech is a durable solution capable of repairing all types of lining designs and has been extensively utilized in the ferroalloy industry. More than 20 UCAR®V Repairs have been successfully performed in South Africa alone. This paper describes the system in general and reviews recent repairs and their unique challenges.

Jan 1, 2014

By P. Tracy

An advanced real-time monitoring system, called a "Tapblock Diagnostic System" is under development to help furnace operators manage the operation and maintenance of their tapblocks. The life of a water-cooled tap block in a smelting furnace ranges from several months to several years, depending on the operating conditions. Tapblocks are typically replaced at regular maintenance intervals; a strategy based largely on historical records and not on the actual condition of a particular tapblock. The Tapblock Diagnostic System monitors the tapblock throughout its life and accumulates probable wear events to help the operator assess the residual integrity of the tapblock. Benefits of this system include the ability to provide early warnings of tap block wear to provide improved safety and maintenance planning. Using cooling-water flow together with copper and water temperature measurements, the system performs calculations that compare the present tapblock performance with the expected operating envelope using a multivariate statistical method (Principle Component Analysis). The operating envelope is pre-calculated for a wide range of operating conditions using transient thermal modeling (Computational Fluid Dynamics). A state indicator in the form of a green, yellow and red light is used to inform operators of the tapblock performance and health status.

Jan 1, 2007

During industrial copper electrowinning, a fraction of the electrolyte becomes entrained with the oxygen gas bubbles that are evolved at the anodes. The fraction of entrained bubbles increases from the bottom of the anode to the top, resulting in a bubble distribution that appears as an inverted wedge between the cathode and anode. Since the bubbles act as insulating spheres, electrolyte resistance increases from the bottom of the electrodes to the top resulting in correspondingly higher local current densities and uneven copper growth along the cathode. To counter-act the inherent tendency toward excessive copper growth near the bottom of the cathodes, the use of tapered anodes was examined. The potential improvement in cathode current distribution was evaluated by comparing the primary current distributions for 2-D computer models of a copper electrowinning cell with plate shaped anodes against one with tapered anodes.

Jan 1, 2007

By Alexander Filotti, Stanley Merjan

"Abstract. The paper shows the benefits and accomplishments of this relatively new but established product on the pile foundations market in the United States. The first part of the paper describes general aspects of the design, construction, and geotechnical capacity (designed and in situ) of Tapertube piles. The qualities resulting from the design and manufacturing of the Tapertube pile will be presented first.The second part of the paper describes the installation of Tapertube piles for an addition to Terminal One at JFK International Airport and The Edge development. A carbon print analysis for both projects is developed using the EFFC-DFI carbon print calculator. For the JFK project the benefits of using BIM in redesigning the project for Tapertube piles are explored.General description.The tapertube pile consists of a tapered tubular bottom section attached to a conventional pipe extension. The 50 ksi steel for the taper is mechanically folded into a polygonal cross-section (usually 12-sided) with a longitudinal welded seam. The tapers are fabricated in many sizes with bottom diameters varying from 8 to 14 inches, top diameters from 12 to 20 inches, lengths from 10 to 35 feet, and steel thicknesses from 3/16 to 1/2 inch. A conical steel shoe or a flat plate is welded to the bottom of the taper and the top of the taper is circularized to match the outside diameter of the pipe extension. The inclination of the tapers is generally between 1.5% and 2.5%.The pipe extension is fully butt welded to the taper and has the necessary length for the pile to develop the requisite capacity. Concrete fill for the piles is generally 4,000 p.s.i. or more. Typically the piles are shopassembled and shipped to jobsites in lengths to 80 feet."

Jan 1, 2014

By Ian Hooper, Alan Winter, Stefan Sadokierski, Craig Covil

The existing Tappan Zee Bridge was built in the late 1950s and has been working over its design traffic load for some time now. A new project, which is being jointly sponsored by the New York State Thruway Authority and Metro-North Rail Road, is looking at new alternatives to provide new road and rail crossings of the Hudson River. These include 2 to 5 mile and potentially longer tunnel crossing options that include hardrock TBM and EPBM opportunities. The paper describes the project needs and tunnel concept design work done on some of the alternatives. It also relates to the current EIS process for the project and talks about a possible double-stacked tunnel option. It also talks about the geology and environmental constraints relating to tunneling and provides and introduction to the tunnel ventilation work necessary for tunnel crossing of this magnitude. It does not report on the bridge engineering options being evaluated.

Jan 1, 2005

By I. Nolet

Matte tapping is one of the most critical operations of a matte smelter. Every smelter has developed particular matte tapping practices and tap-hole repair strategies that are often based on the experience of the smelter personnel. As a result, very little information has been published on these critical topics. This paper aims at providing the information gathered from a survey conducted in the PGM and Ni industries on matte tapping practices and tap-hole maintenance strategies for different PGM-Ni matte smelting operations.

Jan 1, 2014

By Roberto Pena, Cristhian Morales, Darwin Morales, Veronica Cambiaso

"This article makes evident the shortcomings of the current operation of oxygen pipes as well as the damages they cause and why they cause them. When focusing on the causes and effects of these drawbacks, it was possible to develop a new family of thermal lances that could pierce a taphole with the precision of a drill but with the capacity to complete the whole operation. Although efforts have been made to replace oxygen pipes since they are annoying, dangerous and inefficient, nobody had worked to improve the way the traditional oxygen pipe taps/perforates the furnaces and reactors tapholes. In fact, developments made in drills and robotic arms, have failed to replace the oxygen pipe, which despite their negative side effects have been used for more than a century. Observation and theory were key to radically transform this humble tool into a dependable and efficient support in the operation. A good news that it is worthwhile to share for the benefit of all of us, passionate about the world of pyro metallurgy.INTRODUCTION Normally, reports and papers prepared for conventions, symposia or other technical events related to metallurgy aim to relevant topics in the operational field, probably because in them lay the scale economies every company pursues. We intend to give relevance to a matter normally disregarded in operations, but that unmistakably vital: if the furnace or reactor cannot be bled, the pyrometallurgical process will not be completed. Besides, if the tapping task is difficult or is long delayed, the availability of the furnace will be reduced. Consequently, there will be a waste of energy and workers will be exposed to dangerous levels of radiation as well as to work overload and physical injuries Apart from these basic effects, in tapping operations where oxygen pipes are used, we can see serious damages in the smelting furnace, especially in the taphole components such as refractory bricks, taphole jackets and water cooled plates. This paper intends to show that taking care of the tapping task can significantly upgrade not only to the tapping operation itself, but also the whole plant productivity."

Jan 1, 2017

ON mineral lease 38 of the Sulphide Corporation Limited, Broken Hill, a shaft was sunk in the early days Ior prospecting purposes and at the present time it is accessible as far as the 1000-ft. level where a connexion exists with the main workings of the Corporation's Central Mine, mineral lease 9. About the year 1895· a crosscut was driven east from this shaft at the 1330-ft. level cutting the Central Ore-body in mineral lease 9 and the shaft is supposed to extend a further depth of 25 ft; but no records of any of this work are in existence, the whole of the evidence being based on hearsay and memory:Fig. 1 shows the position of the Extended shaft in relation to the main workings. The shaft filled with water to the 1000-ft. level where it overflowed through the crosscut to the main shaft and was pumped to the surface, but when the South drive on the 1300-ft. level was pushed to the southern boundary, it was deemed advisable for safety, to tap the water at this level and so relieve the...

Jan 1, 1919

By Huaqing Xie, Qingbo Yu, Qin Qin

A novel sorption-enhanced steam reforming (SESR) process of hot coke oven gas (HCOG) was proposed for tar removal and H2 amplification, and was studied with the comparison of conventional steam reforming (SCR) process. Both of the processes could remove tar effectively and improve the H2 amount in the COG obviously. For CSR process, after the temperature and the S/HCOG ratio reached 700 °C and 2.4 respectively, the H2 amplification factor kept 4.30 around, with its concentration less than 75%. However, for SESR process, the H2 amount and concentration get improved further, with the optimal temperature moving toward low temperature. At 600 °C and the S/HCOG ratio of 2.4, the H2 amplification factor and concentration could reach 4.91 and 97.55% respectively when the CaO/C ratio was 2.0. Under the respective optimal reforming conditions of the two processes, the energy consumption of the SESR process was lower than that of CSR process.

Mar 1, 2018

By J. D. Miller, J. Hupka

Important aspects of kerosene penetration into tar sand have been investigated. The natural tar sand porosity was measured and used to analyze the performance of the hot water process. Subsequently, pretreatment experiments, using 20-kg tar sand samples (Asphalt Ridge and Whiterocks, Utah) and kerosene as a diluent were carried out at the expected summer temperature (26°C) and the expected winter temperature (-14°C). The natural tar sand porosity accessible by diluent has a crucial impact on the reduction of bitumen viscosity and influences the penetration time required for successful bitumen separation from tar sand by hot water processing. Thus, the tar sand porosity is a critical variable that determines appropriate operating conditions. Experimental results indicate that diluent penetration into the Asphalt Ridge tar sand (high porosity) is almost complete after 30 min, whereas for the Whiterocks tar sand (low porosity) the penetration process is much slower, being still incomplete after 15 hours regardless of the ambient temperature.

Jan 1, 1994

By J. Hupka

Some aspects of kerosene penetration into tar sand have been investigated. The natural tar sand porosity was measured and used to analyze the performance of the hot water process. Subsequently, pretreatment experiments, using 20 kg tar sand samples (Asphalt Ridge and Whiterocks, Utah), and kerosene as a diluent were carried out at the expected summer temperature (26°C) and the expected winter temperature (-14°C). The natural tar sand porosity accessible by diluent has a crucial impact on the reduction of bitumen viscosity, and influences the penetration time required for successful bitumen separation from tar sand by hot water processing. Thus the tar sand porosity is an important variable which determines appropriate operating conditions. Experimental results indicate that diluent penetration into the Asphalt Ridge tar sand (high porosity) is almost complete after 30 min, whereas for the Whiterocks tar sand (low porosity) the penetration process is much slower, and still not complete after 15 hours regardless of the ambient temperature.

Jan 1, 1992

By M Surtees

The Limpopo region in southern Africa is considered to be a favourable target for the discovery of base and precious metal mineral deposits. The integration of gravity, geomagnetic, LANDSAT data and geotectonic history is used to formulate an ore deposit model which can be used in the implementation of mineral exploration programmes. Field work was carried out to test and refine the model.

Jan 1, 1993

By Ulrich Leiste, Andrew Wardlaw, William Fourney

This paper describes the loading on a plate suspended directly over an explosive charge submerged in water. This problem is of interest because it yields results similar to those obtained in the detonation of an explosive buried in saturated soil and thus it is associated with landmines. Recent experiments [1] indicate that plate loading from a submerged charge is similar to that for a buried one, with respect to impulse and pressure. Compared to the buried explosive problem, the submerged explosive case is attractive from a computational point of view; it replaces sand, which is diffi cult to simulate, with water, whose properties are well known. Studying this problem allows modeling uncertainties to be separated from sand simulation issues.

Jan 1, 2008

By Alan G. Galley

"Advances in our knowledge of the petrochemical attributes of deposit environments and of the character and extent of hydrothermal systems associated with certain deposit types has resulted in increased application of lithogeochemistry to exploration programs. Lithogeochemistry can be used to vector an exploration program toward an area of high potential through the use of a series of collapsing scales of analysis from a tectonic subprovince down to a particular stratigraphic segment. In the case of volcanogenic massive sulphide (VMS) deposits this involves the recognition ofsuitable volcanic domains, and the identification of subvolcanic intrusions and cogenetic felsic extrusive complexes. The recognition of chemical vectors within regional-scale alteration zones and associated chemical sedimentary rocks allows the geologist to identify the stratigraphic units with the most potential for hosting a base metal deposit.An integrated lithogeochemical program requires the judicious use of major, trace and rare-earth element and isotopic analysis. Standard discriminant plots may be employed to identify suitable tectonic and lithologic environments. Analysis of the chemical and mineralogical variations in broad-scale, semi-comfortable alteration zones provides a useful set of vectors to VMS mineralization. These may include contouring raw data, element ratios on XY plots, normalizing data against known rock values, or calculating mass changes in alteration zones."

Jan 1, 1995

By D. Marotte, M. David

"A new exploration procedure is proposed for volcanogenic massive sulphide deposits of the Abitibi belt. ""Samples"" of acidic volcanic rocks (Si02 > 60%) were compiled from the literature. From the 574 samples collected, 322 were used in each of a number of experiments. Forward inclusion linear discriminant analysis performed on the untransformed geochemical data shows a general depletion in Na20 and CaO along with an enrichment in MgO for a ""proximal"" group of samples relative to a ""distal"" one. The percentage of misclassified samples reaches 20% to 30%, but test sets shows good stability.The exploration procedure was applied to the Normetal deposit, where the authors took 160 samples during the summer of 1977. It quickly leads to the definition of targets for more detailed exploration together with a good recognition of the old known deposit.IntroductionVolcanogenic massive sulphide deposits in the Abitibi belt (Quebec) are mainly found in rhyolites or acidic pyroclastics in the uppermost portion of a calc-alkaline volcanic series (Descarreaux, 1972). The deposits are thought to have formed syngenetically by the action of volcanic hydrothermal exhalations during the waning episode of a felsic volcanic cycle (De Rosen Spence, 1976). Alteration pipes of disseminated sulphides are commonly present. Metal deposition from hot springs, initiating convection cells in a submarine environment, may have been the dominant process in ore formation (De Rosen Spence, 1976)."

Jan 1, 1981

By Simon Hanner

November 2005 Memorial University Newfoundland and Labrador Mines and Energy Review of Activities Exploration and Mining New Brunswick ?Université du Québec a Montréal McGill University 2005 Manitoba Mining and Minerals Convention Université Laval Quebec Exploration 2005 Saskatchewan Open House December 2005 University of Calgary University of Alberta 'Laurentian University 'Queen's University 'University of Toronto 'Ontario Prospectors Association January 2006 Mineral Exploration Roundup, BC March 2006 Prospectors and Developers Association of Canada Convention April 2006 University of Ottawa Carleton University

May 1, 2006

By Oscar Becerra, Cristhian Tomaduz, Lucas Nunes

Glencore, in collaboration with Cascadia Scientific, conducted a study to improve the haul roads at the Antapaccay mining operation. The study utilized Cascadia's SmartRView platform for data collection, complemented by precise instrumentation installed on both Komatsu and Caterpillar haul trucks Antapaccay worked closely with Cascadia's Data Scientists,employing various statistical methods to analyze the data and identify potential enhancements to the haul road design. The study utilized Cascadia Scientific's heat mapping tool to identify road segments with high fuel intensity . As a result, four main road segments were identified for improvement.

Sep 29, 2023

By T. C. Chudy, C. C. Hamilton, G. R. Lane

The selection and provision of mineralogical services to assist in developing a GeoMetallurgical program for a Cu Porphyry Mine in South America is covered in this paper and presentation. The objectives of the study were to provide a rapid mineralogical scoping protocol to support and confirm results of sequential Cu leach data and to provide detailed mineralogical analysis of four composites and products on which locked cycle test-work were performed. Results showed good reconciliation was achieved between measured chalcopyrite and secondary Cu mineral contents with leach data using a linear intercept mineralogical procedure by TIMA (Tescan Integrated Mineral Analyser), as well as a generally positive correlation between pyrite and Cu-sulphide grain size. Size-by-size analysis of Composite feeds and test products was used to outline comparisons between feeds on a mineralogical basis and provide liberation and association data with which to diagnose and better explain performance. Identifying key mineralogical drivers to Cu recovery and concentrate grades using these results, a greater understanding of the role of chalcocite and pyrite on metallurgical performance was established. INTRODUCTION As a global supply of copper, porphyry copper deposits are typically very large, often in excess of a billion tons of ore (Keeney, Walters, & Kojovic, 2011; McMillan & Panteleyev, 1980) with grades typically between 0.2 and 1.2% Cu, and up to 2% Cu in places. They are also a source of gold. The complexity of copper porphyries arises from their classically zoned nature, the type of host rock, as well as whether or not they have been overprinted by oxidation, weathering and supergene enrichment (Sillitoe, 2011). Zones of alteration and other geological attributes give rise to varied mineralogy, ore mineral textures and material properties, all of which result in different processing characteristics. Due to the interdependencies of geological and processing characteristics, it is vital to study links between the geology at the macro-scale and mineralogical features down to millimeter and micrometer scale (mineral content and texture) and their influences on mineral processing behaviour (Cropp, Goodall, & Bradshaw, 2013). The growing field of GeoMetallurgy aims to provide an Orebody Knowledge framework by which to gather such information as it pertains to: (1) Understanding and predicting likely flotation response; (2) Guiding relevant test work to investigate and validate links, interdependencies, theories and data interpretation/evaluation; (3) Populate a block model with relevant information and; (4) Implement and refine the model for ongoing optimization and control. Specific questions addressed by using mineralogy often include flotation diagnostics as aids to interpretation, causes of dilution and losses to tailings, as well as guidance to sampling for test work (Cropp et al., 2013).

Jan 1, 2019