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By Alaina B. Hanlon

Keywords: Undercooling, Convection, Dendrites, Stainless Steel, Levitation Certain Fe-Cr-Ni stainless steel alloys solidify from an undercooled melt by a two-step process in which the metastable ferrite phase forms first followed by the stable austenite phase. Recent experiments have shown that the lifetime of the metastable phase is strongly influenced by flow within the molten sample. The current research will provide insight to why flow affects the metastable phase. This new understanding will lead to the use of convection to control microstructural evolution in spray-forming of stainless steels. Simulations using a commercial computational fluid dynamics package, FIDAP, yield a range of convective flow velocities that cause mechanical damage to the dendrites which is compared to experimental results. If the convective velocities are great enough that the dendrites bend, then low angle boundaries form at the points of collision. These result in high energy sites that could serve as nuclei for the stable phase.

Jan 1, 2005

By L Olivier, R J. Lowther, J L. Lett, I Brunton

Hydraulic fracturing to precondition the orebody to enhance rock mass cavability is gaining acceptance in underground cave mining applications. Assisting cavability is becoming important as an increasing number of cave mines are being implemented in hard, deep and competent rock masses where clamping stresses are higher and cave column heights may be in excess of 1000 m. Propagating large caves to surface in such conditions can be challenging as risks such as slowed propagation and air gaps can develop during the process.Underground-based hydraulic fracturing is routinely used at Cadia East as a means of preconditioning the orebody to assist in cave propagation, fragmentation and seismicity reduction. This paper presents a summary of a surface-based hydraulic fracture program that was successfully implemented to assist in the propagation of the Cadia East Panel Cave 1 (CE-PC1) cave to surface through competent overlying rock masses. In this case study, the propagation of the CE-PC1 cave slowed as the cave grew past 750 m in height, initiating a Trigger Action Response Plan regarding the cave propagation rate. Surface-based hydraulic fracturing was subsequently used to stimulate the cave to propagate through the final 450 m to surface. The paper details the equipment, strategy, implementation and risk management involved in the program as well as the key learnings.CITATION:Lowther, R J, Olivier, L, Lett, J L and Brunton, I, 2016. Implementation of a surface-based hydraulic fracturing program to successfully propagate a large cave through hard, competent near-surface rock masses to achieve breakthrough, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 83–96 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Enrique Fernandez

M-30, Madrid’s inner ring, covers 42 sq km of the city centre where one million people reside. It was constructed in several phases during the sixties and the eighties. The design criteria applied to those phases were different and were not always homogeneous with urban roads with lighting regulation as well as speedways. These areas had a heavy concentration of access and exits and there had been made many changes on the number of traffic lanes which has caused heavy traffic congestions and high accident rates. The environmental impact and noise pollution in residential areas are also consequences of M-30. The Madrid Major took a decision at the beginning of the present legislation, based on socio economic and environmental evaluation; rebuild the M-30 with the following sustainable mobility principles: Underground transfer of a considerable portion of the main ring and some of its links replacing some parts of the surface with new green areas in order to reduce the environmental impact. Increase the traffic capacity, improving the traffic continuity and fluidity and eliminating the lighting regulation areas, which is one of the main congestion problems currently. Increase the traffic safety with clear signalling information panels and avoiding difficult maneuvering. Redesign the links with the high capacity radial highways and other connecting lanes of the city. The project is worth 3.7 billion Euros. In 2007, when the construction is completed, it is expected will save 14 million of journey hours that represent 4.5 million Euros saved in fuel consumption per annum, There will be a very significant reduction of 35,000 tons of CO2 in terms of pollution and 400 less car accidents. Those values will increase even more in the following years. The areas beside Manzanares River, running parallel to the M-30 on the western side of Madrid, will be highly enhanced. Better water quality and the recovering of the green areas existing in old times will also return for the citizen’s enjoyment. TUNNEL CROSS SECTION OF CALLE 30 SOUTH BY PASS One of the major challenges of the new Calle 30 is actually not only the related to the main road but also to the link with the A-3, with highway to Valencia. This link is currently the most congested area and has one of the highest traffic densities of Spanish roads, with more than 250,000 vehicles/day. The remodelling of this area is the principle objective of the South by-pass. The tunnel is the only answer for this by-pass as the road alignment will go among buildings. A twin tube design, one for each direction, with three lanes allowing the circulation of both, light cars and heavy trucks, is the solution that has been

Jan 1, 2007

By R. W. Heins, N. Street

An investigation was made of the Rehbinder-Kuznetsov pendulum as an instrument to aid in the study of rock drillability and of the effect of surface active agents on rock drillability. The "critical weight", i.e., the pendulum weight at greatest sensitivity, was determined for several solids and it was shown that a change in surface environment changed the maximum value of the apparent hardness but not the critical weight, and the critical weight increased with increase of hardness of the solid used. Using silver halides as the solid material, and solutions of either silver nitrate or the appropriate alkali halide, it was shown that there is a hardness maximum at the zero point of charge of the particular silver halide. INTRODUCTION The development of relative hardness measurement by the method of damped oscillations, or what has been called the pendulum sclerometer, is due largely to the Russian workers P. A. Rehbinder and V. D. Kuznetsov and their co-workers.1,2 The apparent simplicity of the method has led to its use in a number of fields, particularly those where relative hardness has to be determined on a brittle solid. As will be shown, the simplicity of the method belies its complexities. THEORY OF THE PENDULUM SCLEROMETER The operation of the pendulum is quite simple. Make a sharp point such as a diamond, hardened steel or tungsten carbide, as the fulcrum of a pendulum, with the center of gravity of the system below the point of support. The attenuation of this pendulum is a function only of air friction, provided no fragmentation, breakage or other work is performed by the point. However, when the solid surface breaks or disintegrates under the point, and the latter penetrates the solid, part of the energy of oscillation is absorbed in the work of creating new surface, and the rate of attenuation increases. In the case of brittle solids, the point of the pendulum produces fragmentary particles, whereas the point produces plastic deformation in a plastic solid; but in both cases damping occurs. This pendulum damping is a function of the hardness or strength of the solid. Whereas a pendulum oscillating on a hard material attenuates primarily by air friction, in the case of a soft material, the points penetrate the surface of the solid, producing new surface, and the pendulum damps much faster. Thus the attenuation rate is a function of the hardness or strength of a material in both plastic and brittle substances. Russian workers initially used a single support for the pendulum, but this created many problems because of oscillation of the pendulum in more than one plane. A revised version used two points, or sometimes a prism as support, successfully confining oscillation to one plane. The version using two points was constructed and used throughout this investigation, making the recording of the attenuation as a function of time relatively easy. That both points should be in contact with the solid during the damping is implied. Rehbinder (c.f. Kuznetsov2) proposed that the hardness H as measured by this method could be expressed by a quantity which is inversely proportional to the relative initial rate of attenuation of amplitude. where H = hardness parameter (arbitrary units) a, = initial amplitude da/dt = rate of attenuation of amplitude with time. In the simplest case of damping with a constant logarithmic decrement, H can be regarded as a constant for the duration of the whole damped oscillation process. That is

Jan 1, 1966

By M. Makarchian

Existing buildings sometimes experience excessive settlement under their design loads, or due to increased foundation loading, if a change of building use is required. One of the oldest and widely numerical study has been carried out of a simple idealised problem of an underpinned rigid circular foundation to better understand the behaviour of pile used for underpinning and load transfer mechanism from an existing foundation to the underpinning piles. The finite element method has been used for this analysis, with the soil treated as a two-phase elasto-plastic material. It is found that the effect of the length of the pile becomes more significant as pile length increases. As would be expected, the earlier the pile is installed, the less is the final settlement.

Jan 1, 1996

By R. F. Chaiken

The Bureau of Mines has carried out experimental and theoretical studies with prilled and pulverized ammonium nitrate-fuel oil (AN-FO) mixtures containing varying amounts of fuel oil in an attempt to quantify the effects of stoichiometric composition, nonideal detonation behavior, and expansion volume on the production of CO, NO, and N02 fumes. Experimental fume measurements were obtained in the Bureau's large closed gallery facility (7.2 X 104 liter expansion chamber) and in the standard Crawshaw-Jones apparatus (90--liter expansion shamber) using a prepackaged charge configuration containing about 450 g of explosive.4 The theoretical calculation of toxic fumes was achieved with an equilibrium detonation code called "TIGER,," Contrary to initial expectations, the NOx (= NO + N02) fumes from the large gallery test were found to be in essential agreement with the Crawshaw-Jones results. It was also concluded that (1) "TIGER" calculations offer a good approach to the prediction of toxic fumes; (2) there is a basic problem in extrapolating laboratory measurements of CO fumes to mine conditions--this being due to postdetonation oxidation of CO to CO2; and (3) the detonation velocity decay rate of an explosive is a useful experimental parameter for correlating toxic fumes production with nonideal detonation behavior.

Jan 1, 1974

By André Desbiens, Jocelyn Bouchard, René del Villar

"The metallurgical performance of the column flotation process is determined by the concentrate grade and recovery. Although the former can be continuously measured using an on-stream analyzer, the latter must be estimated by a material balance calculation based on seldom verified steady-state assumptions. Consequently, the automatic control and optimization of flotation columns should be performed using secondary variables having a strong influence on the metallurgical performance, such as froth depth, gas hold-up or bubble surface area flux and bias. The aim of this paper is to present a model-based automatic control strategy using froth depth and bias measurements obtained from virtual sensors developed at Laval University. Preliminary pilot plant results on two-phase (water– air) and three-phase system (water – minerals – air) will be presented and eventual industrial implementation of such a strategy as well as the possibility of achieving effective real-time optimization from bias and froth depth measurements will also be discussed.INTRODUCTIONFlotation columns have been widely studied and used in mineral processing for about twenty years. Although a great deal of work has been accomplished to understand the influence of different variables such as froth depth (H), bubble surface area flux (Sb) and bias (Jb) on the metallurgical performance, the measurement of some of these variables is still difficult to be performed – except at the laboratory level – because in most cases, no commercial device yet exists.As a result of this, it is almost impossible to achieve neither efficient control nor optimization of the process at the industrial level, even in open-loop operation. This paper aims at presenting a simple control strategy of froth depth and bias. Description of the sensors used to achieved measurements, preliminary pilot plant results for froth depth control, eventual industrial applications and possibilities for process optimization are also treated."

Jan 1, 2003

By Mark C. L. Patterson

Hydrothermal brines are extracted from significant depths below the surface of the earth and arrive at the surface at elevated pressure and temperature. The exact chemistry and conditions of these brines depends upon the rock formations through which the water travels, but many of the brines are rich in dissolved minerals especially silica which is often saturated in the brine. At pressure and temperature the minerals remain in solution but in order to extract heat from the brines, they need to be cooled and during which many of the minerals precipitate causing problems. Where precipitation is a problem in the downstream processing, the brines are maintained at a high enough temperature and pressure so as to avoid precipitation and injected back into the geothermal formation. This results in a significant loss in potential energy that could be recovered from the geothermal brines. If left to precipitate in an uncontrolled manner, many of the minerals will precipitate as gels, in a high surface area form which is difficult to extract from the liquor and which can causes problems. Precipitation in this manner often builds up on the inside of pipes, reducing the pipe cross-section available for fluid flow and reducing the overall efficiency of the plant. If the brines are seeded at the appropriate time or the precipitation conditions are changed, mineral particles can be grown and separated more easily from the brine. During this precipitation and growth phase the chemistry of the local environment can also be altered to grow more valuable particulates. Some of the specific chemistries will be discussed with reference to known geothermal brines and what needs to be done to precipitate value added products. A theoretical approach to the complete extraction of minerals from geothermal brines is also discussed with the goal of extracting more heat from the brine prior to reinjection into the well.

Jan 1, 2006

[Chairman ZAY JEFFRIES, Vice-chairman S. SKOWRONSKI, Chairman WILLIAM M, CORSE, Secretary Executive Committee J. R. FREEMAN, JR., Local Section G. E. JOHNSON R. S. ARCHER, Non-ferrous Data Sheets P. D. MERICA EDGAR C. BAIN, Journal Committee L. W. SPRING SAM TOUR, Papers Committee F. L. WOLF H. C. JENNISON, Membership Committee Local Section Committee J. R. FREEMAN, JR., Chairman R. J. ANDERSON, Cincinnati R L. DOWDELL, Minneapolis R. S. WILLIAMS, Boston G. H. CLAMER, Philadelphia W. A. SCHEUCH, Chicago R. F, Woon, New York Papers Committee S. SKOWRONSKI, Chairman F. H. DIx, JR.-Aluminum E. R. DARBY-Bronze C. S. WITH ERELL-Copper H. A. BEDWORTH-Brass W. K. FRANK-BRONZE F. W. HARRIS-Copper R. L. SUHL-Nickel H. M. ST. JOHN--Foundry Metallurgy R. S. DEAN-Theoretical Metallurgy]

Jan 1, 1928

By A. C. Wilson

"In 1991, local prospector C. “Mickey” Clement recovered at least three alluvial diamonds from the Michipicoten River. Two of these stones were sent to the Department of Mineralogy, Royal Ontario Museum, where they were identified as industrial-grade diamonds with weights of 1.05 and 1.13 carats. Both stones were described as frosted and graphiteinclusion riddled.In 1995, prospector Sandor Surmacz and geologist Marcelle Hauseux discovered diamonds in bedrock approximately 20 km north of the Michipicoten River. An 18.1 kg bulk sample of a xenolith-rich lamprophyre, taken from an outcrop at the side of the Trans Canada Highway north of Wawa, yielded 1 macro diamond and 5 micro diamonds. All but one was gem quality (Sage, 2000).Since then, more than 36 occurrences of diamonds in bedrock have been reported in an area approximately 30 km2 in size, centred 20 km north of the town of Wawa. The occurrences are hosted within a sequence of unusual, Archean-aged, heterolithic breccias previously considered to have no economic significance. Ten kimberlite occurrences also have been confirmed in the Michipicoten greenstone belt in the last five years. Two of these kimberlites are diamondiferous.To date, expenditures on property acquisition and diamond exploration in the Wawa are estimated at CDN$120 M.This paper summarizes the geological observations made on these occurrences and describes the relationship between the occurrences and the regional geology."

Jan 1, 2004

By William P. Blake

We are so familiar with water in its liquid and its solid form, that we seldom think of it as a mineral, and still less as a mineral product of any considerable industrial importance, though in the form of ice it is mined and stored up in enormous quantities yearly. The industry is peculiarly American, and in no other country has the business of cutting and storing ice been so well systematized and perfected. The interest has grown steadily from year to year, until it has attained large proportions, the annual production being counted in millions of tons, requiring, in the aggregate, a large investment of capital in all the Northern States. It gives employment, also, to thousands of men and horses, in the depth of winter, when farming work cannot be carried on. Ice is not only a luxury, but a necessity, in our climate, and is indispensable in many manufacturing operations: and finds constantly increasing applications and uses. As the industry has grown, so the necessity for suitable implements and tools has grown with it, and it has become necessary to systematize and cheapen the methods of handling such a large amount of material with rapidity and economy. As the industry is properly a branch of mining, and as our mining literature does not, to my knowledge, contain any description of the methods and appliances used in it, it seems desirable to place a brief description on record in our Transactions, and I therefore offer to the Institute the following outline description, based partly upon observations for several years past of the methods and processes employed, and partly upon the information obtained from prominent ice-miners and from the manufacturers of ice-tools. My acknowledgments are particularly due to the firm of W. T. Wood & Co., of Arlington, Massachusetts, for much information in detail, and also to the Knickerbocker Ice Company, of Philadelphia. The wood-cut blocks used in the illustration of this paper, have been kindly lent by both of these firms. The sequence of operations in getting ice is as follows : 1. Wetting down a light snow. 2. Scraping off an excess of snow, if present. 3. Marking out the field. 4. Ploughing and cross-ploughing. 5. Cutting the channel and detaching large floes.

Jan 1, 1883

By James L. Weeks

Introduction This paper attempts to summarize some of the major criticisms of drug testing. Eight problems with drug testing are discussed. These are: • It does not measure something employers have a reasonable need to know, • It is a distortion of priorities, • Drug use is not known to be associated with increased risk of occupational injuries, • Drug testing is proposed as a dangerously simplistic solution to poorly conceived problems, • In the absence of safeguards, it is unacceptably inaccurate, • In the absence of treatment commitments and confidentiality protection for persons dependent on drugs, it is an unethical practice of medicine, • Drug testing is an invasion of privacy, and • It will have a negative effect on treatment of persons with drug or alcohol dependencies. Employers' need to know It does not measure something employers have a reasonable need to know. It is reasonable for employers and fellow workers to want to know if workers are functionally impaired (intoxicated) while on the job. Drug testing does not measure impairment. It measures the concentration of drug metabolities in urine or blood. Unlike measurements of blood alcohol concentration (BAC), drug metabolites are not correlated with impairment or intoxication. They indicate only drug use in the one to two weeks before a urine sample. And, in some instances, they indicate chronic use. Impairment caused by drug use, on the other hand, occurs immediately and declines rapidly within hours. Drug metabolites may linger for days afterwards. Drug metabolite concentrations in urine are a function of (Morgan, 1984; Schartz and Hawks, 1985; MMWR, 1983): • the amount and purity of drug consumed before taking the test, • when the drug was consumed, • whether the person was a chronic user, in which case a certain amount of drug metabolites would be stored in body fat and slowly released, • the person's metabolic rate, and • for metabolites in urine, any dilution effects of urine. Only the first two factors has

Jan 11, 1987

By T. A. Sullivan

Refining in a molten salt electrolyte was investigated as a means of recovering nickel containing less than 1 percent and preferably less than 0.2 percent cobalt from nickel products containing up to 5 percent cobalt. Electrolytic separation of nick and cobalt was accomplished in a molten KCl-LiCl-NiCl2 electrolyte. Nickel containing less than 0.10 percent cobalt was routinely prepared. Factors that influenced the transfer of cobalt to the refined product were the nickel concentration of the electrolyte, the cobalt concentration of the electrolyte, the ratio of nickel to cobalt in the electrolyte, and cathode current densities. A method of recovering the cobalt from the electrolyte was developed. The possibility of preparing high-purity nickel by this process was shown, as well as the preparation of various cobalt-nickel-tungsten alloys.

Jan 1, 1968

By Rodrigo Toro, Ivan Yutronic N

"The Copper Concentrator Plant of Compañía Minera Doña Inés de Collahuasi (CMDIC) is composed of three grinding lines, the third one being the largest. Due to the capacity feature of the third line, specially its SAG mill, it is a priority that the advanced process control team of the Company deploys a supervisory control strategy that allows this unit to operate in an optimal way, in order to achieve the maximum productivity at minimum cost. It is in this kind of tasks where advanced control applications play a key role in obtaining the best economic profit of the process.The advanced process control team, formed by people from Informatics, Automation and Operations of CMDIC have assumed the challenge of generating the transition from a manual SAG Mill 1011 operation (40 x 22 feet, the largest copper SAG mill of the world), to a fully automatic SAG Mill using a multivariable control strategy instead of a rule based on expert control system (widely used in industrial mining process control applications).Therefore, CMDIC decided to work together with Honeywell APC Team implementing an advanced automatic control strategy for the SAG Mill 1011, using for this purpose a technology called Model Based Predictive Control (MPC), based on a variety of control methods that uses dynamical models of the process, obtained from input/output data, in order to print the process knowledge into a group of mathematical relationships that links the constraints (controlled variables) with available commands (manipulated variables) and measured disturbances.The main objective of the advanced control strategy is to ensure process government, tending to throughput stability and optimization, by the execution of coordinated control actions, proactively avoiding measured disturbances effects and the SAG mill overloading.The most important benefits of using a multivariable control strategy are: the automated operation of SAG mill 1011 (that was manually operated before the implementation of this application), a safer, more coordinated and more stable process operation, achieving through this an increase of throughput and a decrease of specific energy consumption, controlling the amount of oversize material production, power consumption, mill loading, noise and torque. In addition to the operational results, this challenge has consolidated a control team, with the participation of engineers and operators, diminishing the typical implementation time and achieving a greater use of the application in a short time."

Jan 1, 2010

Mechanism of Modified Sodium Silicate on Fluorite Ore Flotation

Sep 13, 2010

By J. C. Pandey

The paper highlights the experimental investigations to characterize texture and plastic strain ratio r-Bar in auto grade steel sheets by ultrasonic measurements, whereas attempts were made to characterize interlamellar spacings in pearlite, tensile stresses and torsional properties in prestressed concrete wires by eddy current measurements. Good correlations were obtained between the testing parameters (such as ultrasonic attenuation and velocity in case of steel sheets as well as eddy current out put voltage and phase angle in case of steel wires) and the materials properties (such as texture, plastic strain ratio r-Bar, interlamellar spacings in pearlite, tensile stresses and torsional properties). 15 MHz normal direct contact and 20 MHz delay line normal shear wave probes were used for ultrasonic measurements. Eddy current measurements were done using an absolute coil probe with variable frequency selection. The experimental results show the possibility of nondestructive on line measurement of the above microstructures and properties.

Jan 1, 2010

By Klaus Tietz, Hamish Adam, John Selby, Ian Glazier, Brian Sinfield

"Room-temperature tunable diode laser (TDL) analyzers are gaining in acceptance for highly critical safety monitoring applications in a variety of industries. This paper describes the testing, evaluation and deployment of a laser-based hydrogen cyanide monitoring system at the Campbell Complex of Goldcorp’s Red Lake Gold Mines in Balmertown, Ontario, Canada.A trial, single channel installation was followed by a staged multi-channel installation. Unexpected technical issues with the multi-channel installation were addressed and resolved.INTRODUCTIONLaser-based gas detection has several advantages over existing gas detection techniques (Ballangrud, 1993; Silver, 1992; Bomse, 1995; Table 1). For practical purposes, lasers generate light at a single wavelength. Room temperature tunable diode lasers (TDL) emit light in the near infrared (NIR) part of the electro-magnetic spectrum. Many gases of interest, including HCN, NH3 and others, absorb energy in the near infrared (NIR). Each gas has a unique absorption signature, or spectrum, made up of a large number of individual “absorption lines”. A TDL can be tuned to select a single absorption line of a target gas, which does not overlap with absorption lines from any other gases. Therefore, laser gas sensing is selective and does not suffer from interference from other gases. The single-wavelength nature of laser light also means that laser gas analysers have a linear response over a wide dynamic range.Tunable Diode Lasers (TDL) generate only a few mW of power. However, all this power is concentrated at one wavelength, the wavelength where gas absorption occurs, resulting in high signal-to-noise ratios and short response times, typically of about 1 or 2 seconds (Ballangrud, 1993). This also means that long path lengths can be used, enabling accurate measurements of very low concentrations, even with weakly absorbing gases. Tunable Diode Lasers provide all the advantages of other semiconductor devices: they are small, solid-state devices, operate at room temperature, and have long-term reliability (over 15 years). Currently, they can be obtained for any wavelength throughout the NIR (700nm to 2000nm). Because many gases absorb in the NIR, the technique is widely applicable."

Jan 1, 2011

By David C. Oyler, Dennis R. Dolinar, Christopher Mark, Craig S. Compton

Fully-grouted roof bolts comprise more than 80% of the primary roof supports used in U.S. coal mines. However, nearly 1,500 MSHA reportable, non-injury roof falls occur each year, and most of these are attributable to failure of the roof bolt system. Anchorage failure is one failure mechanism for fully-grouted bolts. As roof deformation works its way upward, the bolts can become heavily loaded near their upper ends. If the applied load exceeds the anchorage, the bolts will simply pull out. Research dating back 30 yrs indicates that this type of anchorage failure is most likely when the roof rock is weak, just where roof support is most critical. In soft shale or coal roof, the small amount of data available in the literature indicates that 20-30 in of resin anchorage may be required to achieve the full capacity of the bolt. In other words, the “full resistance zone” of a 60 in bolt may actually be just 30-40 in. Despite its potential importance, there is no widely accepted anchorage test for fully grouted bolts. Standard pull tests have sometimes been employed, but they provide no information on the anchorage near the top of the bolt. An alternative, first described more than 25 yrs ago in the U.S., is the short-encapsulation pull test (SEPT). With this test, the bolt is installed with only a short (1 ft or less) tube of resin. In recent years variations of this test have become international standards. v

By C. J. Brown

Controlling the level of impurities in copper refinery electrolytes is essential to achieving acceptable cathode purity. Purge of electrolyte is not an entirely satisfactory solution since the cost of neutralization, waste disposal, and replacement acid can be appreciable. The APU® process utilizes ion exchange resin to sorb sulphuric acid while rejecting metal salt impurities. Extensively employed for recovery of waste pickling and anodizing acids since 1977, the system is now being used at several refineries for removal of contaminants such as antimony, bismuth, iron, and nickel. The purified acid, which is recovered from the resin by water elution, is recycled back to the refinery tank-house, while the metals are typically recovered from the de-acidified by-product solution by precipitation.

Jan 1, 2005

By Carl-John Grävare

This paper deals with some of the systems and equipment that are being developed and/or are in use in Scandinavia. The main subject is the development of loading tests on the piles using monitoring equipment. This paper also describes ground improvement using lime-cement columns, expander body piles and steel core piles.

Jan 1, 2000