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By I. Duckworth

P.T. Freeport Indonesia operates a mining complex located in the highlands of Papua, Indonesia. This district consists of underground and surface operations. The East Ertsberg skarn system (EESS) is one of the major orebodies in this district. Subsurface caving of the EESS has been carried out in a systematic series of mining lifts dating back almost 30 years. Present production from the third lift deep ore zone (DOZ), has reached 80 kt/d (88,000 stpd) during 2010, with this rate sustained through 2015. The orebody was proven below the existing caving level, with the next vertical block called the deep mill level zone (DMLZ).

Jan 1, 2010

By Denis Beaudoin

Program Basics: Goals, Course Content & Training Process Sudbury: History of the Program & Lessons Learned Diavik: History of the Program & Lessons Learned Most Recent Program: Totten Mine in partnership with Sagamok Anishnabek Summary -Lessons Learned Conclusion

Oct 1, 2010

By P. Coghill, P. Revell

"Geo-sensing is the ability to routinely measure or infer rock properties at a range of scales using non-destructive scanning devices. These devices can provide information and data flows to support integrated decision making across the minerals value chain. Geo-sensing has been used for many years in minerals exploration using technologies such as satellite imaging and airborne geophysics but to date the use of sensing technologies in between the mine and mill has been very limited. The aim of this research is to develop new mineral sensing technologies that can enable grade engineered ore streams through the rejection of low value gangue or deleterious elements either in the pit or during transfer to the mill. This paper focusses on the research and development being carried out by the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE) and its associated members on new sensing technologies. At the start of their development these technologies were classified on the Technology Readiness Level scale at 3 (TRL3), equivalent to a proof of concept. Laboratory testing and design is aimed at progressing these sensing technologies to TRL5 which is ready for testing at an end users site. New data obtained during the laboratory testing and design phases are presented in the paper demonstrating performance specifications such as detection limits and measurement speed which can be used to infer the pod size of gangue that can be rejected at scale. Grade Engineering® and coarse gangue rejection are considered as key drivers for the mining industry to address the higher mining, processing and environmental costs associated with ore bodies with declining grades. This is an industry wide problem and the development of mineral sensors is seen as key enabling technologies for Grade Engineering® and coarse gangue rejection. The technologies presented in this paper enhance value through early decision making of ore quality and improve the overall resource value case through improved grade and throughput engineering."

Jan 1, 2018

EIA is a test of a development proposalÆs legitimacy and asks two questions: not only æis the proposal competent?Æ but also ædoes the proposal have moral authority?Æ For reasons of miningÆs historic importance and of a scientific and technological industry culture, traditional EIA has focussed on the first on these, an increasingly misplaced priority in a changing world.This paper explains why competence alone is not enough and examines the second of the two questions: what is meant by a projectÆs moral authority, why does it matter, why has it taken so long to become an issue and what, in practical terms, can project proponents do about it.

Jan 1, 2004

By Paul J. Sirkegian

A detail of the guide rollers is shown on Fig. I; and Fig. 2 shows a photograph of a guide roller that has been in service for several months on the haul-back cable. The former practice of supporting and guiding the haul-back cable on slusher hoists at Kimberly was accomplished by using the conventional type of snatch-block pulley, but it was found that an excessive amount of cable whipping and unreasonable wear on both rope and pulley resulted from this type of cable support. The guide, which is wholly made in the Corporation's shops, consists of two vertical and one horizontal roll assembled in a frame that is lagged to the cap timber in a slusher drift. In some slusher drifts more than one guide-roller assembly is used, depending upon the length of the drift. The installations usually are placed at 30-ft. intervals. We have found by actual experience that these rollers have increased the life of the haul-back cable approximately 200 per cent, as compared with the usage of the conventional sheave-block pulley. Cable Care The underground rigging crew and the slusher operators are trained in rope splicing. No cable clamps or knots are permitted on slusher cables and all cable "eyes" are spliced. The standard practice has been to use preformed cables of ?-in. diameter for haulage and ½-in. diameter for the haul back. The preformed cables have proved to be important factors for safety in use and speed in making splices. No external lubrication is used on the cables. It has been found that dry ropes have about 400 per cent longer life than those that were lubricated under these operating conditions. An accurate record is kept of all cable life and the tonnage moved by the slushers in each working place, and if the rope wear is excessive in any particular working place, an investigation is made to determine the reason. Wire-rope Sling for Snatch-block Anchor The rope sling is shown by Figs. 3 and 4. These slings support the snatch-block pulley for the haul-back rope. The standard practice at Kimberly is to use a roller-bearing snatch-block pulley 10 in. in diameter. The snatch-block housings are equipped with a clevis attachment in preference to swivel hooks, as it has been found that the more rigid clevis keeps the cable in better alignment. The snatch blocks are hung from the cable sling, which is wrapped around the posts of the drift sets as shown on Fig. 3. This method of anchoring the pulley provides better anchorage and flexibility than those of the rigid or spring-mounted types. When the slusher-drift headings are being advanced, the snatch blocks are hung from a "gin" pole ahead of the last set of timbers' An employee is assigned on each production shift to take care of the lubrication of all slusher hoists that are being used and he is provided with tools for minor repairs.

Jan 1, 1946

By F. O. Garrabrant, F. S. McNicholas, Robert Henderson, R. U. King

Several years ago, it was decided to experiment with the use of high-pressure water to bring in finger hangups and reduce the amount of secondary blasting necessary. It was argued that the velocity effect of the high-pressure water would bring down hangups without unduly wetting the ore. Water under a head of about 550 ft. was installed in certain slusher drifts. Ordinary ¾ in. water hose, with a nozzle opening of % in., was used, and water was impinged on the fines under a hangup. Results were excellent. About half the total number of hangups were brought in with high-pressure water without blasting and the cost of this part of the slushing operation was reduced about 50 per cent. Operations were speeded up, dust counts and safety hazards were reduced, and a more desirable working place was secured. The additional water added to the ore was under one per cent and caused no inconvenience in slushing, haulage, or crushing operations. Usually the ore would absorb all of the water, so that none of it would enter the loading drifts. The entire mine, developed by slusher drifts, is being equipped with high-pressure water. Heating Mine by Compressor Cooling Water Several years ago, the problem of heating certain sections of the mine during freezing weather became important. It was calculated that there was sufficient heat in the compressor cooling water to heat the incoming ventilating air current to above freezing, if such heat could be transferred from the water to the air. All schemes of radiation from pipe were rejected as too cumbersome, costly and impractical. It was thought that by spraying the heated water from the compressor cooling system into the incoming air, a satisfactory heat exchange could be accomplished. The only objection was that the sprayed water would freeze and might fill the air-intake drift. However, when water at about 75° to 80°F. was sprayed at the rate of 200 gal. per minute through a bank of sprays into the incoming and freezing air current, this air was thereby heated to above freezing; and although some ice was built up in the air drift, the amount was not objectionable. Occasionally the built-up ice was picked down into the outgoing water stream, which removed it. The entire south and westerly parts of the mine were prevented from freezing. Concreting for Hangups Considerable trouble was experienced in securing hangups of fine ore in slusher fingers that needed repairing. Regular methods of timbering were unsatisfactory. Now, a slab of concrete is poured over the top of the muck by Pumperete machine, almost filling a finger, which gives a satisfactory slab to work under for making the needed repairs. Derailers Some trouble has been caused by motor-men not observing safety lights and

Jan 1, 1946

By F. J. Cuddeback

For low-head pumping of small quantities of water, the water jet, or hydraulic educter, has been used to advantage by Eagle-Picher Mining and Smelting Co. in the Tri-State district. Water-jet pumps are used for draining sumps and pockets up to 15 ft. in depth. They have been used very successfully when only moderate amounts of water are encountered in taking up bottom. A small, easily handled unit is desirable in this work, especially while opening and deepening a new stope. Small air pumps are convenient but can be used only on the day shift, when air is available. Obviously, a jet pump of smaller capacity but operating 24 hr. prevents lost time at the start of each shift. No tests have been made on their power efficiency, but admittedly it is low. However, for certain kinds of work this is offset by their handiness, low initial cost, low upkeep, and reliability. They will handle slime and sand without ill effect, and will continue to pump indefinitely on air. This foolproof 24-hr. performance has led to their continued use at some places even after electric pumps with better power efficiency could have been installed. The success of jet pumps depends largely upon a cheap source of high-pressure water. Owing to mine depths in the Tri-State district, pump pressures range from 100 to 150 Ib. per sq. in. In many mines it is common practice to handle the normal inflow water with triplex pumps ranging in size from 3 to 8 in. The pumps operate 24 hr. per day, and, in order to handle emergency conditions, are speeded slightly faster than necessary to pump the normal inflow. The sump level is governed by controlling the by-pass water with a butterfly valve and float. This method is somewhat wasteful of power, but permits the pumps to operate with a minimum of attention. Such an installation is visited once a day to check lubrication. Hence, if some of this water, normally by-passed to the main sump, were used to operate a jet pump, the power cost could be considered low regardless of efficiency. Figs. I and 2 show two water jets that have done satisfactory work. The one in Fig. 2, made up entirely of pipe fittings, may be of interest partially because of its novelty, but does better work than its appearance indicates. The pipe fittings for this jet as shown cost $2.20. Some improvement in its design may be made by cutting out the 135 by 1¼-in. reducer to a smoother taper as shown by dotted lines. A 3-in. suction pipe is sometimes used in order that the discharge may be as straight as possible. A 2-in. discharge line has been used frequently, but 3-in. pipe is used where several hundred feet of discharge is required.

Jan 1, 1946

By Leonel Lopez

Throughout Mexican history, mining has been an important, traditional activity. Before the "Discovery of America," native miners worked a variety of deposits throughout the country, including Mixtec gold and gem mines in Oaxaca State and Aztec gold, silver and copper from mines in Michoacán. The 500th anniversary of Mining in Mexico after the "Discovery of America" was initiated by the Mexican mining sector on April 15, 1991. As early as 1548, when the Guanajuato mining district was discovered, Mexico had become a leading world producer of precious metals. Since then, Mexican mineral production has developed in cycles, responding to changing technological, economic and political conditions. During the 20th century, Mexican mine output reached its peak in the decades of the 1930s and 1940s, when it was producing about 40% of the world's silver, 15% of its lead, 10% of its zinc, 4% of its copper and 3.5% of its gold. In 1990, by way of contrast, these percentages of world output stood at 13.5% for silver, 4.7% for lead, 4.1% for zinc, 3.2% for copper, and 0.43% for gold. The lowest production levels were recorded during the 1960s and 1970s, when Mexicanization of the industry and increasing state controls weakened mineral economics to a point that mineral exploration budgets were sharply reduced or eliminated, along with the industry's future. Only the noble old mining districts continued to supply production, with occasional eruptions of "bonanzas" and new extensions in established mining districts.

Jan 1, 1994

When preparing an appraisal, valuation or feasibility study for a new mining project it is difficult to imagine the technical, economic, social and environmental context that the project will occupy in ten or 15 years time. This paper is about our ability to foresee the future, the choices available now in matching the project to that future context, and about the flexibility that exists in adapting the project to a changing environment. The author draws upon his experience of project reviews, valuations and feasibility studies in the mid to late 1980s in Australia and New Zealand to explore how the project context has changed since key decisions were made and what this tells us about decisions made today for future projects.

Jan 1, 2004

By M. A. Giralico

A new generation of hydraulic efficient pumper and auxiliary impeller designs is the result of an extensive research program focused on improving the overall performance of optimized SX/EW plants. Combined with the proper scale-up, these optimized designs will greatly reduce aqueous and organic entrainment losses, reduce or eliminate air entrainment and crud formation, enhance mass-transfer and maximize the overall copper yield. Currently, these new pumper and auxiliary impellers are installed full-scale in numerous plants ranging in flow rates from 90 to 15000 G.P.M. and developed heads up to 51 inches. Operational results reported by the independent metallurgist at each processing plant are reporting the lowest entrainment results in the industry. Further R&D has just been completed on a new mixing configuration that separates the systems mixing and pumping requirements. Results from the system pilot test document further improvements in reduction of both chemical entrainment and crud formation, while keeping mass transfer stage efficiencies.

Jan 1, 1998

By Kiyoshi Shibata

A new assessment model has been proposed for metal production and its recycling system. The model consists of three processes, smelting of ore, cascading and upgrading of metal scrap. The present approach is to assess the total energy consumption of the system, by introducing two equations for describing the relationships between critical impurity content and the mass of production or scrap recycling. The total energy consumption in the system can be described as a function of recycling rate and performance of the upgrading process. The present model suggests that the impurity removal efficiency and yield in the upgrading process are essential to reduce the energy consumption in the systems. Especially, such points should be explicitly controlled in recycling of aluminum. The potential capability of this model was also discussed by obtaining several quantitative information required for the process design and the operational control of beneficial recycling of metals.

Jan 1, 1998

By Thierry Bernard

To be able to precisely predict the result of a mine blast before pressing the button is a goal for many blasters due to the environmental and economic constraints of our century. Based on the fundamental fracturing of the mechanism of rocks by explosives, the most recent research in digital modeling, the power of present computers, and the possibilities offered by drones, we have designed a realistic digital 3D simulation model for mine blasts

Feb 1, 2020

By Duk-Won Park

A new gage for monitoring fractures in underground openings was successfully developed utilizing the reflection photo-elastic technique. The gage may be used to detect crack initiation in mine openings or tunnels so that remedial action may be taken to prevent further deterioration. Fringes concentrated around the cracks were spread by the use of rubber backing. Crack growth as little as 0.003 inch up to as much as 0.1 inch width were detected in this study. Variation of gage materials will provide alternative ranges. The feasibility of the method was tested and calibration was made in the laboratory study. Field study successfully demonstrated the capability of applications in detecting mine roof crack development.

Jan 1, 1982

By Brian Parsons

In June of 2013, Odyssey Marine Exploration conducted sea trials of the newly installed SeaBat 7150 full-ocean multibeam sonar system on the M/V Dorado Discovery over the Fierberling Guyot in the northeast Pacific Ocean. Fieberling Guyot is located approximately 990 kilometers west of San Diego, California and it rises abruptly from the deep ocean floor (~4300 meters) to a minimum depth of approximately 438 meters. The SeaBat 7150 operates at two distinct frequencies, 24 kHz (shallow to 3000 meters) and 12 kHz (full-ocean depth greater than 2000 meters). Onboard operational data are managed by a suite of state-of-the-art software. A SQL Server 2012 database provides the highly specific management and visualization tools as ArcGIS 10, Micromine 2013, and Geobank 2013 database. The 7150 is mounted on a gondola one meter lower than on previous system and greatly reduces bubble interference. The 7150 generates 880 beams

Sep 14, 2011

By L. Narhi, K. Haavanlammi

"Approximately two thirds of annual nickel production is used as a raw material in the making of stainless steel, and about 60% of these nickel products are in the form of metallic nickel such as nickel cathode or briquettes. In the stainless-steel production process nickel is blended with iron and chrome-based raw materials, and metallic nickel is typically only required for final steel fine-tuning. Outotec offers a new FeCrNi technology to enhance the nickel value chain for stainless steel producers. This involves the use of an HPAL-based intermediate nickel product (e.g., mixed hydroxides or NiO) as raw material in the Outotec FeCrNi process, for the production of a FeCrNi Master Alloy. The new process, designated as the FeCrNi process, offers multiple benefits compared to existing technologies such as: higher tolerance for impurities in the HPAL intermediate product, avoiding the need for further nickel refining, and the improved recovery of all metals in the FeCr process. The complete new FeCrNi value chain is based on proven technologies such as HPAL and the Outotec FeCr-process. This new innovative and promising value chain offers improved efficiencies for the HPAL based nickel production process combined with excellent sustainability aspects.INTRODUCTION In today’s global economy there is a constant need to improve the efficiency and sustainability of the metals production. The requirements for modern metal refining are tightening and cost efficient, safe and sustainable operation is the precondition for all investment. Outotec is offering now a novel way to combine FeCr and Nickel production to create a completely new value chain to source nickel to stainless steel. BACKGROUND Nickel The current nickel mine production is in the level of 2,000 tons annually and it is split 44% from sulphide based deposits and 56% from laterite deposits (Figure 1). Most (40%) of the nickel is refined to pure nickel metal whereas other products are FeNi (19%) and Nickel Pig Iron NPI (20%) (Roskill). The remaining part, roughly 21%, is nickel chemicals and intermediates. Most of the new investments in nickel are in the direct shipping of laterite to produce nickel pig iron. HPAL process is considered in few projects but no major HPAL projects have been started since the Ambatovy plant in Madagascar. Ambatovy reached the commercial production in 2014. The main primary nickel used is stainless steel manufacturing. In the year 2016 about 68% (~1,360 kt) of primary nickel production was used in stainless steel."

Jan 1, 2017

E L. DEGOLYER, our new president, though a petroleum geologist by profession, has always s been associated with mining, for soon after his birth at Greensburg, Kan., on Oct. 9, 1886, his parents moved to Joplin, and when he went, in the course of time, to the University of Oklahoma, he intended to follow his course there with another at a mining school. He became a field assistant in the U. S. Geo-logical Survey, however, while still an undergradu-ate, and after field experi- ence in Montana, Wyoming, North Dakota, Colorado and Oklahoma, he went to Mexico as geologist for the Mexican Eagle Oil Co. This was in 1909, and as a result he was unable to complete his work for his degree until 1911. In Mexico, he located the Potrero de Llaño No. 4, one of the world's largest oil wells, and also the dis- covery well in the Naran- jos pool; and the Colorado School of Mines conferred the honorary degree of : Doctor of Science on him in 1925. On his return from Mexico, he engaged in the consulting business, specializing in financial ap- praisement, the Union and Marland companies being among his clients. In 1919, he organized the Amerada Petroleum Co., with the backing of Lord Cowdray. Last year, control of the company was purchased by an American group, headed by Dillon, Read and Co. Mr. DeGolyer is n o w president of the company. He is also vice-president and general manager of the Rycade Corp, the Rycade Oil Corp., and president of the Geophysical Re-search search Corp. The l a t t e r represents the practical appli-cation of his inter-est in the use of the torsion balance in the locating of salt domes, in which he has pioneered, the Nash dome being the first oil field in America actually brought into production by these methods.

Jan 3, 1927

GEORGE OTIS SMITH, the Institute's new presi-dent, continues the long tradition of close asso-ciation between the organization and economic geology. Several preceding presidents have been eco-nomic geologists, and a gen-erous share of space in the TRANSACTIONS has always been devoted to that subject, one of critical importance to the miner as well as the seeker for ore. Mr. Smith has long served the Institute, hav-ing been a director since 1921 and first vice-president since 1927. He was born in Hodg-don, Me., on Feb. 22, 1871, and graduated at Colby College, where he took his A.B. and A.M. He did graduate work at Johns Hopkins, where he re-ceived a Ph.D. in 1896. Meanwhile he had engaged in field geological work in Michi-gan, Utah and Washington with the Geological Survey. In 1896 he joined the regular staff of that organization, be-coming director in 1907. He has been with the Survey con-tinuously since he first joined, with the exception of one year when he was furloughed to serve as a member of the U. S. Coal Commission. His special interest for many years has been in the eco-nomic aspects, in the larger sense, of the mineral in-dustry, matters that are necessarily the subject of strong differences of opinion, but which he has dis-cussed with good temper though with full adherence to his strong con-victions.

Jan 3, 1928

By A Hollweg, K H. Esbensen, M Lischka

Two new splitter designs for intercepting moving streams of matter are presented, the variable cross-stream splitter (vCSS) and the rotary stream splitter (RSS), which are intended for implementation in a fully automated modus. The vCSS facilitates obtaining up to three subsamples with different splitting ratios from automated laboratory flow paths, while the RSS divides the intercepted sample into 16 equal analytical aliquots. The splitters can process a wide range of dry, granular and free-flowing materials (<5 mm). The required weight for each subsample can be set without mechanical adjustments in the case of the vCSS. Typical applications are subsampling/splitting for X-ray fluorescence pelletisation (or fused beads) or splitting for average shift composite sampling or grain size analysis. The vCSS combines the advantages of riffle splitting (three user-defined subsample masses) with miniature bed blending and can accept up to 15 kg in total incoming sample mass. In practice, the automated vCSS can deal with unlimited ingoing mass fluxes, while the RSS is designed to operate at a user-defined fixed subsampling rate (1/16th in the tested version). Both splitters have the potential to be optimised and evaluated according to an application/user-defined total sampling error (TSE) + total analytical error (TAE) threshold. Both splitters were tested under adverse conditions and with compositions involving three components with properties representing typical mass fluxes and components concentrations in industrial and technological systems: phosphate concentrate 89.00 per cent (<500 µm), slag ten per cent (>2 mm) and glass spheres one per cent (750–1000 µm). The slag particles vary widely in particle shape, aspect ratio and surface roughness, while the glass spheres are extremely prone to bouncing and segregation (spillage). This test system is extremely difficult to split and thus constitutes a realistic worst-case scenario. While the vCSS does not comply strictly with Theory of Sampling demands for correctness, both splitters may well be able to deliver fit-for-purpose representative results if/when tested properly. Average relative mass deviations ranged from 1.89 per cent for phosphate concentrate (relative standard deviations of 20-fold repeated splitting) to 4.72 per cent for glass spheres and 13.04 per cent for slag. For the RSS, the average replication experiment splitting variation was 2.89 per cent for phosphate concentrate, 4.82 per cent for glass spheres and 11.1 per cent for slag. Both new automated online splitters would therefore appear to be able to be tuned to fit-for-purpose representivity (defined here as maximum relative reproducibility <5 per cent) for many non-extreme materials; however, it is always imperative to test every new type/class of material empirically. There is a wide commercial potential for important materials and commodities sectors, including food, feed, drugs (pharmaceutical), secondary raw materials, recyclates, agricultural products and seeds.CITATION:Lischka, M, Hollweg, A and Esbensen, K H, 2017. New online/atline splitter designs for laboratory automation – feasibility results, in Proceedings Eighth World Conference on Sampling and Blending , pp 159–166 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2017

By M. Hamamoto, S. Tanaka, K. Noda

"Tamano Smelter or Hibi Kyodo Smelting Co. Ltd. is operating with the Tamano Type Flash Smelting Furnace method which is a flash smelting furnace without slag cleaning furnace but which can discharge a slag equivalent to that from the slag cleaning furnace and with the development or coke combustion technology which is the basis of this world's only one type flash smelting furnace process, the smelter exhibits a low operation cost under high productivity operation. Utilizing this experience and improving it we have developed and put to practice an operation guide system using a general purpose computer in order to further establish s stable operation. In this paper these improvements are described. Background of System DevelopmentWith the recent rapid progress of general purpose computers and improvements in their performance an environment for the use or computer in process simulation at low cost and simple operation has been established. If an accurate operation simulation can be done with the Tamano Type Flash Smelting Furnace the merits would be very great and thus we started development of the system. The official name of this system is Computer guide system for Coke Combustion in the T-FSF and taking the initial letters we call it CCCT. We aim to achieve operation with stable mane grade, temperature and slag loss in the furnace by maintaining the most suitable combustion conditions of concentrate and coke in the flash furnace with the assistance of CCCT to the flash smelting furnace operators.Through several production expansion projects clone in the past by oxygen enrichment the copper concentrate treatment quantity and matte grade have increased step by step as shown in Figure I. Following this increase the difference between the operation calculation results al the initial stage of coke combustion and the actual behavior of furnace (matte grade. temperature in the furnace. etc.) gradually became bigger. Further operation procedures taken by different operators against the same phenomenon were sometimes different depending on each individual, which from time to time caused the operation to become unstable. Prior to the development of the system we checked out thoroughly the weak points of operation calculation procedures which were in practice until that time. The results were analyzed and study was carried out to establish a most suitahle operation calculation procedure and finally we reached this system"

Jan 1, 2000

By M. Hopf, E. Rossouw

Keywords: Pyrometallurgy, furnace, copper coolers, freeze lining, monitoring, Saveway The use of water-cooled copper components as sidewall elements of submerged arc furnaces and other pyrometallurgical applications has become increasingly common. The high cooling efficiency of copper has made it possible to increase the service life of furnace refractories when compared to conventional refractory linings. However even the self-healing effect of ?freezing? worn areas of the lining does not necessarily protect the copper coolers against wear or corrosion completely. In order to avoid furnace explosions, various methods have been used to monitor the wear of coolers. Unfortunately, these have not been able to consistently identify localized wear. Thos Begbie (South African) and SAVEWAY (German) jointly developed technology to embed a line sensor into the copper cooler during the casting process. This system allows an exhaustive monitoring of the copper cooler. A SAVELINE sensor is placed inside the copper-cooling panel between the water-cooling passage and the hot face of the panel. The sensor follows the meandering shape of the cooling water channels. In the first instance, the sensor provides analogue information as the thickness of the copper reduces. Secondly, this wear signal will be confirmed by a signal of interruption if the sensor is washed away. Because of the structure of the sensor, a self-diagnosis is possible and indications can be confirmed (double proofed). Subsequent to the manufacture of some test pieces, coolers for a large submerged arc furnace were manufactured. The sensorized coolers have been installed at the intermittent surface (slag line) where the largest amount of corrosion has been encountered. The system has been operating since December 2005 in what is considered one of the largest submerged arc furnaces in South Africa.

Jan 1, 2006