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By Mirjana Boskovic

LKAB’s Kiirunavaara Mine is a sublevel caving iron-ore mine located above the polar circle in northern Sweden. The mine has been proclaimed seismically active since 2008 after a magnitude 3 seismic event, according to Swedish National Seismic Network (SNSN). At that time the Kiruna Mine did not have mine-wide seismic system. Since then, the Kiruna Mine experienced several damaging seismic events of which the largest one on the May 18, 2020. The magnitude, based on the moment tensor inversion results on data from the SNSN as well as seismic stations in Finland and Norway, is estimated to 4.2 ± 0.2 moment magnitude. The seismic event on the May 18, 2020 was located in the middle of the one of the productions areas and caused the major damage in the mine, damaging several kilometres of drifts on six mining levels, some of them beyond the practical repair. These damages affected four of ten production areas on several levels, some more some less. Luckily, no person got injured from the seismic event and the very long aftershock series. An important part in the whole process after the seismic event was information flow and decision-making process. It was very important to keep workers and community informed as that contributed transparency of decision-making and decreased the speculations. Resuming the production in the damaged areas in the safe manner, very soon become main focus for the mine management. It was obvious that not only rehabilitation of the areas is needed to resume the production. It was A MUST to understand the factors behind the seismic event and its mechanism to be able to avoid same situation and prevent seismic event of similar size. Mine engineers had to think outside the box to find the solutions to ‘rescue’ every drift that they could to be able to make good enough base for continued mining of the area. The paper describes actions taken in a very complex process of recovering the area that we from the beginning thought need to be abandon. Seismological analyses of the event on May 18, 2020 and past activity in the area, damage mapping, detailed studies of structures and geology, numerical modelling as well as engineering judgement were used as base for all our decisions how to proceed in attempt to restore mining of the area heavily damaged by 4.2 moment magnitude seismic event, in a safe way.

Apr 26, 2022

By F. M. Doyle, K. Sreenivasarao

Copper and cadmium metal has been recovered from dilute (3 X 10-4 mol/dm3 ) chloride solutions by ion flotation with dodecysulfate, followed by electrolysis. This approach should facilitate treatment of effluents too dilute for effective direct electrolysis. . The adsorption density of metal dodecylsulfate complexes on bubble surfaces was estimated from surface, tension data, and compared well with experimentally-observed metal removal kinetics, and ultimate recoveries. Copper and cadmium were recovered by electrolyzing the foamate, using steel wool cathodes and a graphite anode. The stability constants of the copper and cadmium dodecysulfate complexes are estimated, and used to analyze the thermodynamics of electrolysis. Dodecysulfate was unaffected by the electrolysis process, and hence could be recycled to ion flotation. A conceptual flowsheet for an overall effluent-treatment process is presented.

Jan 1, 1997

By S. B. Sargent, V. J. Collins, Lester C. Uren

[The conclusions arrived at by authors in paper read before the Petroleum Division and the California Sections of the Americam Institute of Mining and MetallurgicaI Engineers and the Standardization Division of the American Petroleum Tnstitute, at a joint session held at Los Angeles, Cal., Jan. 21, 1926, are presented below.] From the theoretical discussion and experimental evidence presented in this paper, the following conclusions may be drawn: 1. The efficiency of the oil-well plunger pump is dependent to an important degree upon the submergence provided. 2. Ample submergence must be secured in order to provide sufficient static pressure to force the oil through the restrictions interposed in the oil path at the standing valve and at the plunger nut surrounding the garbutt rod. These restrictions should be no smaller than is structurally necessary, in order to reduce resistance to oil flow to a minimum. 3. A part of the static pressure developed below the standing valve by submerging the pump is dissipated in overcoming the inertia and in providing upward acceleration for oil left between the pump valves at the conclusion of the down-stroke of the plunger, and of oil below the standing valve in the gas anchor above the oil inlet. This loss in effective static pressure can be reduced to a minimum by dispensing with the garbutt rod and placing the working valve at the lower end of the plunger. The valves should be as near together at the conclusion of the down-stroke of the plunger as is consistent with security in avoiding striking of the lower end of the plunger on the standing-valve crown. Gas anchors should be short, and oil inlets should be as near the standing valve as is consistent with proper gas exclusion. 4. Because of the presence of gas in solution in the oil, which tends to escape from solution under the reduced pressure conditions above the standing valve, the effective length of stroke of the plunger is reduced, and the suction effect of the rising plunger is largely nullified. The influx of oil through the standing valve is therefore chiefly dependent on static pressure developed by submergence.

Jan 1, 1927

By D. J. Salley, M. Burke, G. L. Simard

A PREVIOUS paper1 described experiments on the interaction of dithiophosphate with galena and suggested that the process had characteristics of both chemisorption and surface chemical reaction. In order to add to this knowledge, a study has been made of the competition of a second ion with the dithiophosphate for a galena surface. Use again was made of radiotracer methods. Since radiophosphate was readily available, it was chosen as the competing ion. It is a feature of the tracer method that, in spite of similarity in the chemical behavior of the ions, the measurement of one ion in the presence of another can be made as simply as if only one ion species were present. In order to study the competition effectively, it naturally was necessary to examine the interaction of phosphate with galena alone as well as in the presence of dithiophosphate; consequently, this report consists of two parts. The first is devoted to a study of the rates, the isotherms, the desorption, and the exchange in the phosphate-galena system in the same manner as was done for the dithio-phosphate-galena system. The second portion is concerned with the studies on the competition. Flotation experiments on the three-component sys- tem are also outlined and the relationships involved are discussed briefly. The experimental method was that of the previous paper. The preparation of the galena, the radioactive and the nonradioactive dithiophosphate, and the procedures for radioactive counting, for sorp-tion, and for flotation measurements were identical to those previously employed. The radiophosphate* was used in the form of disodium phosphate solution. In the competition experiments the effect of the phosphate ion in depressing dithiophosphate uptake was followed by holding the initial concentration of nonradioactive phosphate constant while varying the initial concentration of the radioactive dithiophosphate. Counterfashion, the depression of phosphate by dithiophosphate was obtained by keeping the initial nonradioactive dithiophosphate ion concentration constant and altering the initial concentration of the radioactive phosphate ion. All solutions were buffered at a pH of 7.8 a0.1 by 20x10-' mol per cc of sodium carbonate. Measurements with radiocarbonate indicated that little or no carbonate could be sorbed in the presence of

Jan 1, 1952

By Prosper Lamothe

El presente texto describe los distintos métodos y criterios empleados en la valoración de yacimientos o activos mineros de Chile, asimismo se realiza un análisis comparativo de los distintos métodos para explicar las distintas distorsiones, errores, riesgo e imprecisiones de cada uno de ellos. En este sentido, las empresas son concientes de los riesgos y el impacto que tienen en el valor comercial, los modelos de estimación de recurso y las reservasmineras. mineras. Por ello, las opciones reales son actualmente la técnica que permite valorar y controlar en cierto modo la cobertura de riesgo del negocio.

Sep 12, 2005

By S. K. Kawatra, T. C. Eisele

"Recent advances in microbiology have made the application of biotechnology to metallurgical processes possible. Hydrometallurgy stands to gain the cost from the use of microorganisms, as they are useful for both dissolution aids and for removing metals from solution. The development of genetic engineering techniques promises to greatly increase the importance of bioprocessing of metals and minerals by the year 2000.In this paper, the basic effects of microorganisms on metallurgical processes are reviewed, and the applications which are currently either in use or near being used are presented. Representative data collected at Michigan Technological University is also given.IntroductionMany hydrometallurgical operations exist which are thermodynamically possible, but which are industrially impractical due to slow kinetics, high reagent costs, or the need for a highly corrosive environment. However, recent discoveries in microbiology indicate that in many cases these difficulties can be reduced greatly by the action of bacteria and other microorganisms (1-8).A major advantage of using living organisms in hydrometallurgy is that once the culture is established the microorganisms produce their own reagents either from the material being processed or from low-cost nutrient supplements. They thus allow extremely complex chemical reactions to be carried out at reasonable cost. The major drawback of using microorganisms is their inability to tolerate extremely high temperatures, excessive concentrations of toxic metals, or very highly acidic, alkaline, or corrosive conditions. However, the complex reactions which bacteria make possible frequently eliminate the need for such extreme conditions. Also, in recent years a number of organisms have been isolated from such exotic environments as hot springs and deep-ocean vents which can tolerate temperatures higher than was previously thought possible for any organism, and can catalyze a number of metallurgically important reactions (8)."

Jan 1, 1988

By Raja V. Ramani

As the new millennium approaches, it is appropriate to assess the progress that has been made in mine health and safety, a matter of concern to management, labor and government. One can hardly look at the major events of the last century — from the birth of the US Bureau of Mines through the enactment of the modern health and safety laws — without realizing that the march has been relentless toward eradication of health and safety threats in mining. The progress is spectacular in mine safety and significant in mine health. In looking at the future, it is safe to assume that societal demands will increase for improved health and safety conditions in the workplace. So will the demands for greater technological leaps. The standards will for measuring success and the expectations of progress in creating a safer and healthier mine environment will grow. The possibilities are enormous of meeting these exacting requirements in the 21st century.

Jan 1, 1999

By M. Sengupta

Surface mining in arctic regions is characterized by many unique problems. Continuous and discontinuous permafrost (perennially frozen ground) occurs in most of the arctic and subarctic areas. Permafrost presents special problems of slope stability. Stability of permafrost depends on its temperature, moisture content and material type. Permafrost slope fails due to solifluction, disturbance of ice rich slopes, and liquefaction. Drilling and blasting of frozen ground present special problems. Depending on their degree of saturation with water, freezing soils and rocks have a number of important characteristics that affect blasting efficiency. Metals used in mining equipment and mining structures require special selection. At low temperatures many steels lose most of their normal ductility and toughness (resistance to brittle fracture). The paper discusses engineering solutions to unique problems of arctic mining.

Jan 1, 1986

By Joel L. Morrison

The preparation of coal-water slurry fuel (CWSF) has the potential to be a commercially viable technology for the coal industry. The technology base required to prepare stable CWSF using grinding circuits has been developed over the past decade and is now being applied to the preparation of CWSF from wet coal fines which are generated during coal beneficiation. When preparing CWSF, the optimum CWSF formulation must be determined to ensure that the fuel will be stable while having acceptable atomization and combustion properties, and the production run must be monitored closely to ensure that the CWSF quality is maintained. This paper describes the CWSF formulation process, CWSF preparation circuits, and some of typical problems encountered in, and solutions to, the transportation and storage of CWSF.

Jan 1, 1993

By M. D. Bishop

Early solvent extraction circuits in the uranium industry utilized bona fide kerosenes as diluents for extractant chemicals. These kerosenes were used successfully in the uranium industry; however, at least one plant was destroyed by fire resulting from the use of a low flash point kerosene. Although the term "kerosene" is used throughout the solvent extraction industry, the authors have been unable to find any use of kerosene in copper solvent extraction circuits. A term that is occasionally used with reference to diluents is "metallurgical kerosene." Such a term is unrecognizable in the petroleum industry. Kerosene [or kerosine] is a flammable hydrocarbon mixture that is less volatile than gasoline. It is produced for combustion purposes and may have variable compositions of organic compounds including alkanes, alkenes, alkines, and aromatics. Diluents are constant composition hydrocarbon mixtures developed specifically for use in solvent extraction processes. These products usually have much lower vapor pressures and higher flash points than kerosene. In solvent extraction systems, they typically comprise 70 to 95 v/o percent of the circuit organic. The primary purpose of the diluent is to adjust the extractant concentration to the working range of the operation. The diluent and extractant must be completely soluble or miscible with each other. Secondary diluent effects are to promote transfer kinetics, optimize phase disengagement, and minimize both organic in aqueous and aqueous in organic entrainment.

Jan 1, 1996

By Kefton H. Teague

Attempts to locate domestic supplies of sillimanite have been unsuccessful until recently. This paper describes recent discoveries of sillimanite-bearing schists in the Southeastern States, with emphasis on geology of the deposits, mineral composition, origin, and reserves. Statements concerning possible methods of mining, milling, and utilization of sillimanite are given. Results from refractory tests on a laboratory scale are summarized.

Jan 1, 1950

By Georg Keintzel

The origin and elimination of 3rd octave mill chatter is a frequently investigated topic since tandem cold mills are in operation. So far only chatter monitoring systems have been successfully deployed, but this implies speed reductions and therefore a significant loss in mill output. Primetals Technologies has developed a new system using active injection of damping in order to eliminate 3rd octave mill chatter. The new hydraulics-based ChatterBlock® Control has now been proven successfully in mill operation. 3rd octave mill chatter, typically occurring in a frequency range between 90 and 150Hz, is a self-excited vibration phenomena typically occurring in the rear stands of tandem cold mills. It can produce significant gauge variations and even cause strip breaks. 3rd octave mill chatter is characterized by a quickly diverging vertical vibration of the rolls for specific rolling conditions (material, mill speed, forces, gauge etc.). Its occurrence requires immediate speed reduction of the mill in order to avoid strip breakage and/or strip quality degradation. This phenomenon thus severely limits mill productivity. The first step to proof the industrial feasibility of the new system was its installation on stand no. 4 of a 5-stand tandem mill. The development process and first results of the industrial implementation will be presented in this paper.

Aug 16, 2017

By M. K. Gangal, M. A. Stoakes, A. E. Hall

"The major features of the CANMET thermodynamic mine ventilation network program, developed by the Mining and Mineral Process Engineering Department of the University of British Columbia for the Canada Centre for Mineral and Energy Technology (CANMET), are described.The program is designed for use by deep Canadian mines in planning ventilation flows where the effects of auto-compression of air, moisture lift work and natural ventilation are significant. Routines to simulate stalled fans and give an optional cost printout have been included in the program.A supplementary plotting program used to simplify data interpretation is also described.The program is described with a test data example of a deep mine. It is a valuable analytical tool which can assist ventilation engineers to simulate many alternative ventilation strategies at a low cost in a very short time.IntroductionCanadian underground mines are becoming deeper and more extensive. The use of more and larger diesel-powered equipment increases the amount of air required to be circulated in these complex systems. These effects, coupled with the increasing unit cost of the energy required for mine ventilation, require that the air is used with maximum efficiency.Optimum airflow distribution can be obtained by using network computer programs enabling engineers to plan future ventilation systems based on quantitative assessments. The programs used for deep mines must make allowance for the change of air density with depth, as the assumption of incompressible flow leads to serious errors. Natural ventilation effects may vary with depth and from part to part of the mine; this must be catered for by the program. The air moisture content changes throughout the circuit and a significant portion of the fan work may be used in removing moisture from the mine; as this work varies directly with the flow, a suitable relationship must be utilized in the program."

Jan 1, 1982

By T Nassis, H M. Nel, T du Toit

Assmang Khumani Iron Ore Mine is exploiting the iron ore deposits that can be found in the Bruce-King-Mokaning farm areas in the Northern Cape, South Africa. The Bruce, King and Mokaning (Khumani) deposits are approximately 10 km south of the town Kathu, adjacent to the Sishen Mine. Assmang Limited is jointly owned and controlled by African Rainbow Minerals Limited and Assore Limited.Measurement, calculation and trending of plant throughput and chemical ore properties are critical in maintaining a successful beneficiation operation due to these values forming the basis of decision-making and thus promotion of efficient ore extraction. The Khumani management and engineering information system (MEIS) supplies information on key process parameters to an operational team and is required to do so within an optimal time frame, for maximum impact.Diverse data is put into the MEIS from multiple specialist systems, with interfaces that require manual intervention. Manual intervention is resource and time intensive to the point which limits the effect on the process and decreases the potential for value addition.Automation of interfaces decreases resource and time requirements, standardising plant wide data sources and providing the opportunity to provide specialist system data to decision-makers in a timely fashion, resulting in maximum impact on the process output.Engineering and metallurgical management systems were interfaced at Khumani Iron Mine by means of an automated table which facilitates the transfer of production data validated within the engineering system as input to the metal accounting system. This interface effectively assigns a master to each specialist data set employed for decision-making and delivers accurate process parameters to the production team within an optimal time frame, resulting in increased potential to improve beneficiation efficiency.CITATION:Nel, H M, Nassis, T and du Toit, T, 2013. The role of metallurgical and engineering information systems in the optimisation of iron ore beneficiation processes, in Proceedings Iron Ore 2013 , pp 453-458 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By Mary Nelima Ondiaka, Kayode Henry Talabi, Oladunni Oyelola Alabi, Fatai Olufemi Aramide, Francis Gitau

Iron ore is essential in steel making; however, high-grade ores have diminished, making low-grade ores inevitable. These lowgrade iron ores need further beneficiation to upgrade the iron content. Currently, traditional physical and chemical methods are utilized and are not environmentally friendly. Bio-beneficiation techniques have emerged as a sustainable alternative for mineral recovery. This review delves into recent bio-beneficiation advancements for enhanced low-grade iron ore recovery using microbes. Research has revealed that bio-beneficiation methods such as bio-leaching, bio-flotation, and bio-flocculation have proven successful in iron recovery from ores. The bio-beneficiation process occurs in mild conditions using bio-reagents derived from microbes and offers a reduction of chemicals used in processing. Bio-beneficiation of iron ore potentially offers a relatively energy-efficient, cost-effective, and environmentally friendly method of maximum iron ore recovery. However, this review has identified a scaling-up difficulty in which a future approach for industrial-use applications is offered following a thorough sustainability assessment. Bio-beneficiation, using microbial processes, provides a viable avenue for maximizing iron ore recovery while tackling the constraints of dwindling high-grade iron ore resources and environmental sustainability.

Mar 16, 2024

By S. Kelebek, A. Khan, J. Caceres, Beckett. D.

"Pyrrhotite in nickel-copper sulphide ores is nickeliferrous and intimately associated with pentlandite. Due to its low nickel content, pyrrhotite rejection is an important step in processing of these ores. In our laboratory, various reagents were investigated for their effect on pyrrhotite depression. Among these, a combined use of triethylenetetramine and sodium metabisulphite was found highly promising.The work described in this paper has two parts. The firs part is a summary of results obtained on process samples from the pyrrhotite rejection circuit at Falconbridge’s Strathcona Mill. The second part involves simulation of the circuit performance based on the reagent conditions used in the experimental work and the concept of split factors.Two sets of reagent conditions were evaluated. The first one involved baseline conditions, simulating the current reagent performance. The second one simulated the impact these new reagents can have on the circuit performance.The simulation results obtained under baseline conditions indicated a good agreement with the current circuit performance. The simulation results suggest that at practically the same pentlandite recovery and tailing grades, the circuit concentrate nickel grade can be doubled through effective pyrrhotite rejection by these new reagents."

Jan 1, 2003

By L Smith, R Beckie

Controls on environmental loading from acid rock drainage (ARD) are not well understood in waste rock material. In particular, relationships between subsurface flow and the timing, duration, and intensity of leaching of metals and acidity from waste rock dumps remain ill defined. This study investigates field-scale relationships between subsurface flow processes and geochemical processes in unsaturated waste rock. A 12-metre tall, unsaturated waste rock pile, constructed in 1994, was deconstructed and sampled at Key Lake, Saskatchewan, Canada, during the summer of 2000. A detailed sampling methodology was developed to characterise physical and chemical properties of waste rock material within the waste rock pile. Physical properties were characterised by measuring soil-water suction, volumetric water content, and grain-size distribution at 60 random locations within the pile and grain-size distribution at 20 grid locations within the pile. Attempts to develop a field-based soil water characteristic curve from physical field-data failed due to spatial variability and hysteresis of waste rock properties. As a result, grain-size distribution was used as a relative measure of subsurface flow. Paste pH, pore-water geochemistry, mineralogy, and water-soluble extraction results were used to characterise geochemical processes and sulfide oxidation at each of the 20 grid locations. Geochemical characterisation results demonstrated the preferential weathering of marcasite relative to pyrite and chalcopyrite. Dolomite was the main buffering carbonate mineral. Gyspum, jarosite and iron oxyhydroxides were the main secondary minerals. Pore-waters contained up to 800, 11.7, and 6 mMolar (78 000, 690, 1400 mg/L, respectively) of sulfate, nickel, and uranium, respectively, suggesting significant weathering has occurred. Measures of weathering indicators show no discernable correlation with grain-size distribution nor do they show any spatial relationship within the sampled grid. Reasons for this may include limited duration of waste rock exposure to weathering and development of fluid flow-paths, and limitations of characterisation methods used. Indeed, six years may not be long enough for weathering patterns to develop due to fluid flow-paths in this unsaturated waste rock pile.

Jan 1, 2003

By Tassos Grammatikopoulos, Gary Pearse, Massoud Aghamirian, Charlotte Forstner, Stephen Mackie

"SGS Minerals Services (Lakefield, Ontario site) has conducted a number of developmental and pilot programs that examined methods for the beneficiation, extraction and recovery of lithium from a variety of spodumene containing hard rock sources. An overview of the beneficiation programs is presented separately by Aghamirian, Mohns, Grammatikopoulos, Imeson & Pearse (2011). The focus of this discussion will be the hydrometallurgical steps involved in producing a high grade lithium carbonate (Li2CO3) sample from the spodumene concentrate. SGS has applied the standard Li2CO3 hydrometallurgical flow sheet to a number of spodumene concentrates and has determined that all of these samples respond in a similar manner to the process and produce a final product having a Li2CO3 grade of >99.5%. The standard process is sufficiently robust to accommodate the observed variability in the concentrates that have been tested. Advantage of one spodumene deposit over another will thus be gained through process optimization and innovation. Optimization at the beneficiation stage and at the hydrometallurgical stage must be considered. Some aspects of the process optimization of the hydrometallurgical flow sheet will be presented.INTRODUCTION The current activity in the exploration, development, and mining of lithium based minerals is due in large part to the key role that this metal plays in the rechargeable battery industry (U.S. Geological Survey, 2011). Lithium battery technologies are widely applied in a range of portable electronic consumer products. The expanding development and production of hybrid and fully electric vehicles has contributed to the increased interest in finding and developing new lithium sources in order to meet the expected demand from the lithium battery industry. Lithium may be sourced from continental brines (sub-surface salars), hard rock minerals (pegmatite, spodumene), hectorite clay deposits, geothermal brines and oilfield brines. Currently the majority of the lithium products are produced from Li brines. The four major lithium producing countries are Chile, Australia, China, and Argentina (U.S. Geological Survey, 2009; Roskill, 2009). These countries accounted for 97.6% of the total lithium produced in 2010."

Jan 1, 2012

By S. S. Klima, D. E. Pollock, J. A. Organiscak

"Airborne respirable coal dust capture by water sprays or wet scrubbers has been studied and developed over many decades as an engineering control to reduce dust exposure in coal mines and combat coal worker pneumoconiosis. Empirical relationships and deterministic models for particular dust capture experiments have previously been devised to show the key parameters involved in airborne coal dust capture. Many of the results from these models show that the significant parameters related to airborne dust capture are water spray pressure, water quantity, water droplet size, relative water droplet-to-dust particle velocity, and total operating air pressure of the scrubber. However, many airborne dust capture efficiency relationships and models developed for particular experiments cannot be readily applied to forecast the dust collection efficiency of different spray and scrubber design configurations, which rely on several key dimensional engineering measures. This study examines engineering measures from previous water spray and wet scrubber experiments conducted by the U.S. National Institute for Occupational Safety and Health (NIOSH) and the U.S. Bureau of Mines (USBM) to develop empirical models for wet collection of airborne dusts. A dimensionless empirical model developed for predicting airborne dust capture efficiency of water sprays and wet scrubbers is presented. IntroductionWater sprays have been one of the earliest mainstay engineering controls used to suppress respirable dust in underground coal mines. Some of the earliest reports of water spray usage on continuous mining machines indicated respirable coal mine dust reductions of 20 to 60 percent (Kobrick, 1970). Not long after the enactment of the 1969 Coal Mine Health and Safety Act, the U.S. Bureau of Mines (USBM) and others conducted extensive research into water spray and wet scrubber systems to control respirable dust in coal mines. The primary aspects of water spray dust control included prewetting for dust prevention, localized ventilation redirection and airborne dust capture, which are summarized in handbooks or best-practices guides (Kost, Yingling and Mondics, 1981; Kissell, 2003; Colinet et al., 2010). Initially, underground studies were conducted to identify the primary sources of dust during the mining processes and effective dust controls (Courtney, Jayaraman and Behum, 1978; Jankowski and Organiscak, 1983). Laboratory research systematically studied ventilation and airborne dust capture effects of water sprays and scrubbers to improve their application in underground coal mines (Tomb, Emmerling and Kellner, 1972; Divers and Janosik, 1978, 1980; Grigal et al., 1982; Ruggieri et al., 1983; Jayaraman, Jankowski and Kissell, 1985; Volkwein, Ruggieri et al., 1985; Jayaraman, Schroeder and Kissell, 1986; Divers, Jankowski and Kelly, 1987; Jones and James, 1987)."

Jan 10, 2018

By K. H. McDaniel

The Waste Isolation Pilot Plant (WIPP) is adding a third fan to operate in parallel with, and supplement, its two existing main fans. An engineering analysis conducted in 1995 identified the need for improved system availability and efficiency. The WIPP, located near Carlsbad, New Mexico, is a U.S. Department of Energy (DOE) Carlsbad Area Office facility designed to permanently dispose of U.S. defense-generated transuranic waste in a deep bedded salt deposit. Engineers at the WIPP performed a feasibility analysis for either modi tying, supplementing, or replacing its two main mine fans. Since the centrifugal fans were installed in 1988, multiple operational and performance concerns have been identified. A comprehensive engineering study was conducted (McDaniel, et al., 1997) to: identity and quantity operational concerns, evaluate possible alternatives, and recommend an optimum solution. The study indicated that adding a third single-duty centrifugal fan similar to the two existing fans, and equipping that fan with Inlet Van Controls (IVCs) was the best choice. This alternative provided the most desirable combination of operational readiness, and improving system performance. The fan installation project accommodates several operational and scheduling constraints. WIPP is scheduled to receive waste in May 1998. This milestone is proceeded by an operational readiness review. Fan installation could not be allowed to compromise the WIPP's ability to declare facility readiness and had to minimize operational disruptions during the system tie-in. All engineering for the project is completed and physical modifications started in July 1997. The project was completed in 1998.

Jan 1, 1999