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By I. Imris

The chemical industries are using different type of catalysts, which after application usually produced many tons heap of residues. One of them is cupric oxide catalyst with high content of copper and silica. The recovery of copper from the waste has become major interest from a viewpoint of environmental protection and recycling of resources. The thermodynamic analysis and experimental results suggest that the copper from cupric oxide catalyst can be extracted by plasma reduction process. By plasma reduction process the inert slag and copper with following chemical composition: 99.04 % Cu, 0,042 % Fe could be obtained.

Jan 1, 2007

By F. Chevarin

The reaction of O2 with the carbon anode is considered as the main parasitic chemical reaction affecting Hall-Heroult process anodes. The current study aims at investigating the influence of the microstructure of baked anode on its overconsumption. Samples were removed from different positions of an industrial anode. Density, porosity, Lc and BET specific surface area were measured. The anode reactivity was evaluated based on the weight losses for the samples resulting from the reaction of anode with air at 550°C after 7h. The essential parameters determined to control the air reactivity are closed porosity, Lc and pores with a pore entrance radius of 1.5, 8.5 and 12 p.m. The knowledge of effects of these parameters allows better understanding of the reactivity of anodes and consequently reduction of their overconsumption in electrolysis bath.

Jan 1, 2011

By D. R. Wright

"The modest thermal efficiency of the steam turbine cycle essentially determines the heat required and, therefore, the coal consumption and ash production of pulverized-coal-fired powerplants. This paper emphasizes how some properties of coal and its ash can crucially affect the operation of a steam generator and its flue gas cleaning equipment. A brief reference to some siting factors and economics reaffirms the all-pervasive influence of the properties of coal and ash and establishes the importance of a firm supply of cooling water. The economics of scale remains a compelling factor in selecting the size of units, despite disappointing performances by some of the larger units. Environmental considerations suggest that smaller units still have a role to play. IntroductionCoal fuelled one industrial and economic revolution, beginning two hundred year s ago . It was the precursor of competing fuels, notably natural gas, oil and uranium, which eclipsed it in terms of convenience and rate of growth.The turmoil that now exists because of rapidly dwindling supplies of no-longer-cheap oil and the concerns about nuclear energy-justified or unjustified-exacerbated by an operating incident at the Three Mile Island Nuclear Powerplant, prompt speculation for a resurgence of coal, especially where it cangenerate electricity to replace energy from imported oil.The world's reserves of coal are not inexhaustible, although they are ample for several decades. Of greater import is the fact that the world's coal reserve s are more widely distributed than its oil reserves, and they appear less convenient as instruments of economic and political persuasion by opportunist powers. The crux is whether or not the world will accept all that a massive, if temporary, return to coal implies.Combustion of pulverized coal in steam generators to pro duce electricity is a 50-year-old, well-understood technique; it is undergoing continuous refinement to meet evolving environmental and economic criteria and is not found wanting. It is certainly the only technique available and technologically advanced enough to replace oil immediately on a large scale. Although it may take a decade to bring a new coal-fired powerplant into service, this delay is a reflection on nontechnical and administrative processes. Capital and operating costs of coal-fired powerplants are significant and subject to inflation, but, because of the accumulated experience in this field, the ability to control costs is better than for those energy processes which are less mature or still in embryo form. More exotic, soft energy systems, touted as the panacea for world energy problems, have still to prove themselves on the scale they are needed and under the stringent climatic and operating conditions coal-fired powerplants have already mastered."

Jan 1, 1980

By W. Yang, R. Rajasingam, K. Mohanarangam

"Copper Electrowinning (EW) is a complex electrochemical process that involves the production of LME grade copper from copper rich electrolyte. The process involves the deposition of the copper ions onto the cathode from copper rich electrolyte with the production of oxygen bubbles at the anode. The process setups up a complex flow pattern within the cell as it is subjected to varying density gradients due to the deposition process along with oxygen bubble driven flow. It is a necessity to understand and quantify the flow behaviour within these cells in order to maintain the production of highest grade copper. In fact, the oxygen bubbles originating from the process is responsible for the generation of acid mist which is a designated as a carcinogen a major health hazard around EW tank houses. Hydrodynamic assessment of the process has so far been restricted to simple mass balances and some limited numerical modelling. All the models are based on assumed boundary conditions which has not so far been verified by any real-time physical measurement. This apparent gap has led to models which could not be directly used to track process changes or troubleshoot problems in EW tank houses. In order to address this gap, CSIRO has established a full size (width and height) transparent cell capable of simulating plant operating conditions (across the range currently used). With the use of sophisticated diagnostic analytical tools and measurement techniques it was possible to study all the operating variables (current density, flow rate, temperature, etc.) independently and their effect of bubble size, bubble velocity, gas hold-up as well as acid mist generation and its size. In order to address safety concerns in tank houses around acid mist early results outlining the factors contributing to its generation as well as the effect of various barriers to mitigate acid mist is outlined below.INTRODUCTIONA significant part of today’s copper production is through hydrometallurgical route which predominantly involves leaching, Solvent eXtraction (SX) followed by ElectroWinning (EW). Producing copper using this approach have shown to be environmentally friendly (Dresher, 2001) compared to the traditional smelting process. EW is the final step in the production of LME grade copper using the hydrometallurgy route. The electro-chemical process involves the use of a lead anode (Pb-Sn-Ca) and a stainless steel cathode to produce copper sheets using the copper rich electrolyte from the SX process and with the applications of direct current to the electrodes. This electro-chemical reaction results in the deposition of copper ions on the cathode with oxygen released from the anode as a by-product. Hydrodynamically, the oxygen bubbles create a bubble driven flow within the EW tanks with the surrounding electrolyte. A direct result of this could be seen from the quality of the copper deposited on the cathode. Most of the copper plates produced from the traditional tank houses have a rough texture at its bottom one-third while the top two-thirds have a smooth finish with a finer grain structure."

Jan 1, 2016

By J. A. Hansuld

"THIS SESSION marks something of a milestone in that it is, as far as I know, the first session at a CIM Annual Meeting devoted entirely to exploration geochemistry. This is an indication of the general acceptance and widespread recognition by industry of geochemistry in mineral exploration. As a first, I hope it proves sufficiently successful and interesting that geochemical exploration sessions will become a routine part of future CIM annual meetings. The greater use and acceptance of geochemistry has resulted in many investigations and advances, especially in areas such as the Canadian Shield. For a first session on geochemistry, the meeting in Quebec suggested an ideal opportunity to assess these advances and report on the current application of geochemistry in the Shield. The theme of the session is ""Geochemical Exploration in the Canadian Shield - The State of the Art."" A series of six papers will be presented dealing with the various dispersion media - rocks, heavy minerals, ""soils"", lake sediments, waters and vegetation. As a background to the individual presentations, I would like to take a few minutes to briefly trace the history of the use of geochemistry in the Canadian Shield."

Jan 1, 1971

By M. Walawalkar, C. K. Nichol, G. Azimi

Rare earth elements (REEs) are essential to the production of technologically advanced products, including wind turbines, electric and hybrid cars, automotive catalytic convertors, hand held electronic devices, and military defense systems. Their application in environmentally beneficial technologies puts them at a high priority for ameliorating environmental concerns. Because of their increasingly high demand and limiting resources, it is highly beneficial to find new sources for them. The present study is focused on leaching REEs from a phosphate based fertilizer by-product, known as phosphogypsum (PG). Global estimated world production of PG is about 240 million tonnes that is stored in the form of wet stacks adjacent to fertilizer production facilities, occupying vast amounts of land. PG also contains trace metals, which are detrimental to the environment, and hence it is crucial to monitor these stacks. We obtained our PG sample from Agrium Inc. (a fertilizer manufacturing company in Canada). We performed a comprehensive characterization of the PG sample and found that it predominantly contains Y, La, Ce, Nd, and Sm. For leaching purposes, we used hydrometallurgical acid leaching techniques. We investigated three acids over a range of operating conditions such as acid concentration, temperature, solid-to-liquid ratio, and residence time. We achieved an average leaching of 81% with hydrochloric acid as leachant using operating conditions that can be easily replicated in industrial settings. If our process is implemented, not only will it reduce the size of the existing PG stacks (mitigating their environmental risks), but also enable the development of new innovative routes for extracting REEs, making countries like Canada less vulnerable to supply disruptions.

Jan 1, 2016

By J. H. Pee, Y. J. Kim, H. U. Lee, G. H. Kim

The general recycling process of tungsten scrap to produce tungsten raw materials (tungstic acid, ammonium paratungstate (APT) and WO3) have been carried out by the oxidation, milling, sodium-fusion, dissolution, and extraction processes. Many studies on the high temperature oxidation of tungsten scrap have investigated various aspects such as swelling kinetics, fracture resistance, and the effect of alloying composition. However, the accelerating factors on the scrap oxidation rate during oxidation were not considered here. In general, oxidized products were fused with sodium carbonate or sodium hydroxide to produce Na2WO4. Later in the process, solid Na2WO4 was dissolved in water. This process required considerable reaction time and was a costly process. Therefore, the aim of this study was to increase the solubility of solid oxidized products to produce Na2WO4 solution by hydrothermal reflux method. Na2WO4 solution was used to produce CaWO4 and H2WO4 by general chemical reactions with calcium chloride and hydrochloric acid. Ammonia solution was also added to the tungstic acid to produce APT. In this study, the effect of ammonia addition on the APT precipitation process was investigated in detail.

Jan 1, 2015

By Shoma Sinha, Nirmal K. Sinha

Deformation in a material at any temperature is known to consist of two major components - a reversible (elastic) part and an irreversible part (often called plastic). What is not universally known is the fact that at high temperatures greater than about 0.4Tm, where Tm, is the melting point in Kelvin, the reversible part includes not only elastic but also a delayed elastic (recoverable but time dependent) component. A very simple computational model is presented here for a constant-strain stress relaxation test (SRT) on the basis of a three-component constant-stress rheological equation derived from strain relaxation and recovery test (SRRT) data. It is shown that the rapid stress reduction during the early periods of relaxation when the stresses are high is governed primarily by delayed elasticity irrespective of the imposed strain level. This is in contradiction to the popular concept prevailing today. The asymptotic approach to a quasi-stable stress rate at longer times and lower stresses is, however, controlled by viscous flow (power-law creep). The validity of the theory is examined by comparing the predictions with experimental results obtained for a titanium-base alloy Ti-6246 at 0.45Tm.

Jan 1, 2004

By W. E. Newton

THE following notes are offered primarily to show that industrial minerals or their products have a much more important place in the metallurgical industry than is perhaps generally realized, and with the hope also that some statement by the metallurgical consumer of the relative merits of various materials for particular requirements or services will l;>e of value to the industrial mineral producer. These notes are not in any way presented as complete. Also, some of the statements made may be debatable. The grouping adopted is as follows: (1) Refractories; (2) Fluxes; (3) Construction materials; and ( 4) Miscellaneous applications. Fuels are not dealt with in the present paper. REFRACTORIES GENERAL: Refractories are materials which will withstand high temperatures with-out melting or becoming markedly soft or pasty. While their primary function is to withstand heat, they are usually called upon to resist one or more of the following destructive influences: abrasion, pressure, corrosion by slags or fluxes, and rapid changes in temperature. Refractory materials may be conveniently divided into three classes: (1) Acid refractories-consisting of silica, or containing silica as their chief constituent. They combine more or less readily with metallic oxides, forming silicates, and are hence termed 'acid'. The most important of these are quartz, quartzite, siliceous sand, tripoli, Dinas rock, and ganister. Most fire-clays, although generally considered neutral sub-stances, contain relatively small amounts of free silica and are, to that extent, acid. (2) Neutral refractories-the term is merely relative in most cases, since, at high temperature, many of the refractories that are classed as neutral will react chemically with a strong base, functioning as a weak acid; or, conversely, with a strong acid, functioning as a weak base. Chrome and graphite are the most nearly neutral of all the commonly used refractory materials.

Jan 1, 1936

By A. W. White

Introduction To discuss all the technical details of incorporation laws, security laws, underwriting procedures, codes, and ethics-as laid down by varous associations -would be impossible in the time which has been allotted to me. My remarks, therefore, will be made in a very general way and will naturally be coloured with experiences which my firm and I have had. There is a common expression that "money makes the mare go". I hardly have to mention here that the best prospect in the country is of very little value unless its prospects can be developed-and this requires large capital expenditures. The art and problems surrounding the raising of this money is a long and interesting story. Since by its very nature mining is risky, the appraising of its risks in the many phases of its development programme is continuous. Very few men-if any-and very few corporations -if any -can afford to take all the risk of mining. Because of taxation policies-and the very scheme of present-day living -the truth of this statement can be seen throughout the whole industry by a close examination of the records. Since this is so, it is essential that the mechanics of distributing risk on a sound, and equitable basis be known to those engaged in the business and to the investor or spectator who proposes to risk his funds in the industry. Perhaps the greatest stimulant to modern business activities has been the creation of corporate bodies. It is evident, from the number of charters being granted by various jurisdictions, that this method of doing business is becoming more and more important. A limited company -or corporation-can be defined as a fictitious person existing solely in contemplation of the law.

Jan 1, 1951

By Ata Akcil, Z. B. Karshigina, Ye. G. Bochevskaya, Z. S. Abisheva

"Phosphorus slag is the most heavy-tonnage waste of yellow phosphorus production, which is stored in the dump fields for many years creating ecological problems in the regions. Despite of the actions taken to utilize the slags, most of them remain in the slag disposal area. One of the relevant and priority directions is rare-earth metals production (REMs), presence of which in the phosphorus slags allows considering the latter as an acceptable raw material source. Phosphorus slags contain about 30–40 wt% of silicon dioxide, therefore they can serve as a source of production of precipitated silicon dioxide highly required in different industries.The purpose of this work is the most complete REMs recovery in the solution while leaching and subsequent processing of siliceous cake. The work shows results of researches on establishment of the chemical and phase compositions of phosphorus slags, determination of the forms of presence therein of REMs compounds, processes of phosphorus slag leaching by nitric acid and processing of produced siliceous cake by NaOH solution.Based on the data of the instrumental and chemical methods of phosphorus slag analysis, it was established that it consists of pseudowollastonite a-CaSiO3 for 90–92%. It was found out that REMs are present in it in the form of carbonate apatite Ca10(PO4)6CO3 or rare earth apatite, and La2S3 compound inclusions.Optimum parameters of phosphorus slag leaching process were selected: HNO3 concentration 7- 7.5 mol/L; L/S ratio = 2.6–3 mL/g; temperature – 50–80o?; duration – 1 h; pulp stirring – 500 rpm. Recovery of SREMs, CaO, Al2O3 and Fe2O3 into the solution were achieved at 98.0, 99.1, 99.0 and 18.8%, respectively. Presence of 10 elements of the rare earths group in the phosphorus slag was established. It was found out that recovery of almost all REMs is within ~92–99%, except for Sc and Lu – ~39% and ~28%, respectively.For the purpose of optimization of siliceous cake leaching by NaOH solution, influence of some physical and chemical parameters was studied: N?O? concentration, L/S ratio, temperature, and duration. Results of the experimental data will serve as a basis for development of the technology of complex processing of the technological waste of phosphorus industry with production of REMs concentrate and precipitated silicon dioxide."

Jan 1, 2016

By O. A. Ojo, N. Esmaeili

"The effects of brazing and use of composite powder mixture as interlayer material on hot corrosion resistance of brazed IN738 superalloy were studied. Brazing was observed to result in significant reduction in the hot corrosion resistance of the superalloy. However, application of composite powder mixture, which consists of additive superalloy powder, enhanced the hot corrosion resistance of brazed samples. It is also found that although the use of composite powder mixture increased hot corrosion resistance of brazed alloy, if the additive powder completely melts, which is possible during brazing, it can significantly reduce the hot corrosion resistance of the brazed joint. Elemental micro-segregation during solidification of the joint with completely melted powder mixture produces chromium depleted zones and consequently reduces hot corrosion resistance, since a uniform distribution and adequate chromium concentration is necessary to combat hot corrosion. This has not been previously reported in the literature and it is crucial to the use of composite powder mixture for enhancing the properties of brazed superalloys.INTRODUCTION Superalloys have been developed in response to the increasing demand for materials with higher resistance to corrosion and creep and also with higher mechanical strength at higher temperatures (Smith, 1981). Ni-base superalloys are predominantly used in manufacturing hot sections of gas turbine engine components. This is due to their high strength and corrosion resistance in extremely high temperature service environments which is typical for hot sections of gas turbine engines (Miglietti, 2009). The continuous demand for higher efficiency and output has resulted in the use of higher operating temperatures and gas pressure in modern gas turbine engines (Jahnke & Demny, 1983). Consequently, this has caused thermal and mechanical stresses which result in severe degradation and damage of gas turbine engine components due to creep, fatigue and hot corrosion (Zhang, Feng, & He, 2006). The decision to replace or repair damaged parts depends on the overall repair cost and expected life of the repaired components (Jahnke & Demny, 1983). However, in most cases, it is more cost effective to repair damaged parts rather than use a full replacement."

Jan 1, 2017

By H. C. M. Gordon

IT is essential to the success of any mining op::ration that the roadways through which the material wrought and ocher materials and supplies are to be transported should be kept in such condition that this transportation cart be effected rapidly and without difficulty. The longer the roadway and the greater the tonnage to be taken over it, the more necessary it becomes chat the construction and maintenance of the road be such chat traffic delays can be reduced co a minimum. le is proposed co deal with the development and construction of roadways serving longwall operations and, since a recreating system of longwall is worked, as a rule, only where roadways driven in the solid coal can be readily maintained, the discussion will be confined co advancing longwall roads which are driven through areas from which the coal seam has been totally extracted. In order to construct a roadway through extracted ground in such a manner that it will remain in a state of reasonably good repair without undue maintenance, it is necessary chat everything possible be done to bring the overlying strata co a state of equilibrium as quickly as this can be effected, and the operations should be so planned that future workings will not disturb the equilibrium so set up more than can be avoided. Obviously, the readiest way to obtain a stable roadway is to develop it by tunnelling through a settled waste. However, this cannot always be done, as some of the roadways must be developed and constructed as the walls progress, but level or lateral cut-offs can be constructed in this manner. Main-slope roads can be developed in a similar manner after the coal has been extracted and a waste formed for at !east five hundred feet on either side of the line of the permanent roadway from temporary subsidiary roads developed for this purpose along one or other of the flanks of the waste to be formed. This interval must be obtained in order chat the lacer extraction of the seam will not set up movements in the waste immediately overlying or adjacent to the constructed roadway, thus upsetting the equilibrium of the strata and distorting the road.

Jan 1, 1940

By Gareth Barnes

Traditional approach to improvement is driven by good ideas from good people, but whilst the business case may sound good, when the project is complete, we often have not delivered on expectations.  Why not? The best way to successfully predict the outcomes of an improvement effort in a complex process is through using statistical modelling, which considers the impact of uncertainty within interacting processes.  Applying Theory of Constraints in a model helps leaders to quickly determine: Where the constraining process(es) is/are Where improvements will add the most value How much improvement should be targeted - before the next constraint takes over The confidence level of achieving a given target, which gives us a clear pathway to improvement. This paper presents an analysis of statistical modelling applications at Vale’s Manitoba Operations to achieve the 2025 targets. Using statistical modelling of the Business Structure, the team identified a series of process improvements through a Theory of Constraints Analysis. Value Stream Maps (VSMs) were used to define the required data, apply statistical modelling, and conduct training sessions enabling the Manitoba team to identify the constraining influences. Scenario testing in the Statistical models helped identify the Hierarchy of Constraints and specify the pathway to improvement. How to Improve a Business Video link https://vimeo.com/344418155

May 4, 2025

By H. Clare Horwood

"Fractures and fracture zones containing veins and stringers of auriferous quartz in a quartz porphyry dyke are the principal structural features at the Howey and Hasaga gold mines. The 'break' containing the dyke was produced by a force from the northwest, the fractures in the dyke by compressive stress from the west.Both mines are in the north-central part of Heyson township, in the Red Lake area. They lie close to the southeastern side of the Dome granite stock. The Howey mine exhausted its ore reserves and ceased operations in November 1941. The Hasaga mine is producing at the present time (June, 1946).Mineralization was first discovered in the dyke in 1925 by the Howey brothers. Lorne Howey's discovery, which became the Howey mine, came into production in April, 1930; Ray Howey's find, which is now the Hasaga mine, started production in November, 1938.The total production from the Howey mine was 421,324 oz. gold and 144,253 oz. silver from 5,158,376 tons of ore hoisted ( 4,319,331 tons milled) during its 11 years of operation.The total production from the Hasaga mine from November, 1938, to December 31, 1945, was 124,434 oz. gold and 51,009 oz. silver from a total of 901,098 tons hoisted (721,361 tons milled).GENERAL GEOLOGYThe porphyry dyke containing the orebodies at the Howey and Hasaga mines lies a short distance southeast of the contact of a granite-granodiorite mass known as the Dome stock. The dyke fills a fracture trending N.65°E. in a tongue of Keewatin volcanic breccia that extends in a rather irregular manner into an elongate intrusive stock of dioritic rock known as the Howey diorite. The accompanying table presents the geological succession."

Jan 1, 1954

By Andrew Dobson

The assessment and control of environmental noise from mines has become increasingly important in recent years, due to urbanization and population growth, increased regulation of environmental factors, and overall awareness and sensitivities to noise exposure. Minimizing adverse effects on communities and achieving compliance with local ordinances is now commonplace, and consideration of noise during the design and/or operation of a mine cannot be ignored. Ventilation equipment can represent the loudest and most bothersome equpiment at mines, however there are complexities when attempting to control the assocaited noise, due to the acoustical nature of mine vent fans. In fact, the utilization of traditional and/or industry standard methods can intensify the noise impact, or simply not work as intended. This paper provides recommendations on specific noise control methods that are suitable for mine ventilation equipment, based on recent assessment work and field experience.

Oct 1, 2024

By Horace Freeman

"IN THE writer's opinion, the most important industrial re-search problems in Canada concern development of technology for the treatment and commercial utilization of the recent discoveries of v.ast quantities of easily concentrated iron ores in both eastern and western Canada. They exist in both magnetite and hematite forms. The subject is doubly important because of the lack of metallurgical coking coal in Canada. Methods for utilizing our lower grade eastern and western coals for reduction purposes must be developed. We are fortunate in our supplies of oil and gas, which can supply the heat requirements for processing or for thermal electric plants, which are now competitive with hydro-electric plants in the industrial areas. These are among the reasons which have prompted the writer to continue the development of the co-current rotary kiln direct-reduction process outlined •in his report to this Institute at the 1956 Annual Meeting ( 1) in the face of the scepticism which has surrounded the numerous costly failures in 'sponge' or 'direct' iron production. The work involved in bringing the concentrating ores of Canada to the metallic state involves, firstly, concentration of the ores; secondly, preparing the concentrates for reduction; thirdly, reduction of the 'reconstructed' ore; and finally the steel making process. These briefly will be dealt with in order, giving emphasis to the most important of these steps, the reduction process which is the main subject of this paper."

Jan 1, 1959

By D. Shishin

Continuous integrated experimental and thermodynamic modelling work is conducted in Pyrometallurgy Innovation Center (PYROSEARCH). The target is to develop a tool, which is capable to predict the compositions of phases, phase equilibria and enthalpy balance for pyrometallugical processes with higher accuracy. All these can be achieved by thermodynamic calculations based on Gibbs energy minimization algorithm. Recent developments made it possible to predict important factors, such as the chemical solubility of Cu in slag as a function of matte grade, temperature, P(SO2), Fe/SiO2 ratio in slag, wt% Al2O3, CaO and MgO in slag. In industrial practice, it is not only chemical solubility, but the overall amount of slag, which affects the recovery of copper and other valuable metals. It will also impact the energy balance. The presence of solids in the slag matrix influences the physical entrainment of matte in slag. Oxygen enrichment which is sometimes used to control the temperature of the furnace, may also affect the volatilization of minor elements into the gas phase. Same is true if additional fuel is used to compensate for heat balance. In other words, all key process parameters mentioned above are interrelated. Present study demonstrates the ways thermodynamic modelling can be used to link those process parameters on the example of copper smelting. INTRODUCTION Research methodology involving integrated thermodynamic modelling and experimental approach has been recently reported by the authors (Shishin, Hayes, & Jak, 2018 Shishin, Hidayat, Jak, Decterov, & Belov, 2016). Present paper reviews the updates and discusses challenges in the development of a large self- consistent thermodynamic database. The database covers the Al-Ca-Cu-Fe-Mg-O-Pb-S-Si-Zn-(Ag, As, Au, Bi, Ni, Sb, Sn) chemical system. The database works in the environment of FactSage software Bale et al., 2016 and related family of products: ChemApp (Petersen & Hack, 2007), ChemSheet and SimuSage. A list of phases, and thermodynamic models is shown in Table 1. For the copper industry, most important phases are Gas, Slag, Spinel and Liquid matte/metal/speiss. Black-colored elements represent the base system, elements in green can be considered as slag modifiers (slagging elements), and elements in red are minor. Ni is highlighted because it was included recently, in 2019, and currently under development. In addition to copper, the database covers the conditions typical for lead and zinc pyrometallurgical extraction. It is developed in consistency with the experimental results for high concentrations of Pb and Zn. Examples of applications in the present study include the thermodynamic analysis of fluxing for an agitated copper reactor to show the effect of Fe/SiO2, and calculations of copper slag cleaning using reductant.

Jan 1, 2019

By K. Forsberg, A. Rasmuson, R. Rodriguez Varela, J. Martinez De La Cruz

"This study analyzes the separation of rare earth elements by means of a supported liquid membrane (SLM) with the final objective of recovering REE from an apatite concentrate (Alemrajabi, Forsberg, & Rasmuson, 2015; Mohammadi, Forsberg, Martinez de la Cruz, & Rasmuson, 2015). In this study, the feed phase consists of an aqueous phase containing REE, the membrane phase contains the organic solvent and carrier (D2EHPA and EHEHPA), and the stripping phase is a hydrochloric acid solution. An evaluation of mass fluxes, separation efficiency, and membrane performance is conducted. In order to analyze the suitability of liquid membranes in the extraction of REE, a deeper insight into the mechanisms causing instability is needed. In this study, surface tension is considered as the key factor of Marangoni instabilities and spontaneous emulsification.INTRODUCTIONThe demand of REE and their compounds has increased considerably due to their special physicochemical features that make them crucial elements for numerous high-tech applications, including wind turbines, hybrid cars, mobile phones, and defense technologies. They are also extensively utilized in traditional industries such as nuclear energy, petroleum, metallurgy, agriculture, and textiles (Xie, Zhang, Dreisinger, & Dyole, 2014; Zhang, Wu, Bian, & Zeng, 2014).Solvent extraction is widely used for the separation of REE (Xie et al., 2014; Zhao, Huo, Pan, Li, & Liu, 2014). Di-(2-ethylhexyl)-phosphoric acid (D2EHPA) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHEHPA) are two of the most effective extractants for the separation of rare earth elements among organophosphorus extractants (Gupta & Krishnamurthy, 2005). However, the difficulty in stripping loaded D2EHPA extractant, especially for heavy REE, has limited its utilization. Yttrium can be stripped at lower acidities in EHEHPA systems compared to D2EHPA systems (Gupta et al., 2005), but the extraction efficiency is lower. Conventional solvent extraction by mixer-settlers is restricted by its large solvent inventory and loading limits, and suffers from phase disengagement, emulsification, loss of solvent, and flooding problems (Swain, Jeong, Lee, & Lee, 2007). In this context, supported liquid membranes (SLMs) present a potential alternative due to their advantages, being low solvent inventory, process simplicity, low energy and operational costs, great enrichment ratio, and combination of extraction and stripping into one single step. A SLM is a system in which two aqueous phases are separated by an organic liquid membrane suspended in the pores of a porous support by capillary forces. One of the aqueous phases is the feed solution with the solute and the other is the stripping or receiving solution. The solute diffuses through the liquid membrane and then is extracted into the stripping solution (Kislik, 2010)."

Jan 1, 2016

By S. Konetschnik, Lux Degel, R. Degel, T. Haslinger

UrbanGold and its partners from Mettop and SMS group have developed a novel technology for the recovery of valuables from all non-ferrous metals’ fractions of WEEE (Waste Electrical and Electronic Equipment), with a special focus on low qualities which are commonly landfilled or incinerated. The technology is marketed under the brand name “UrbanGold Flex” to illustrate the high flexibility in respect of plant design and raw material portfolio, allowing also the processing of low grade material and materials with high caloric values. The process of the technology’s centrepiece, a modified and enhanced bath smelting furnace called “HENRI”, was investigated in numerous pyrometallurgical trials as basis for a scale-up towards a capacity of up to 100,000 tons of WEEE-concentrates per year. All relevant facility components have been evaluated in respect of references, fall-back options, as well as exit strategies (alternatives) to minimize risks when establishing a novel technology. A spin-off within the development is the “UrbanGold Compact” technology which can be seen as optimization of state-of-the-art smelters by using an optimized TBRC as primary processing unit. As an UrbanGold Compact plant will be the first industrial scale reference of UrbanGold’s technologies, it is also explained in the publication. As precious metals recovery is of major (economical) importance when recycling WEEE, major attention has been given to minimize the losses of these valuables. These measures, as well as a sophisticated way of utilizing waste heat as far as possible, result in interesting business cases with gross profits of up to 20% or even more. INTRODUCTION Over the past years, the demand of electrical and electronic equipment has increased dramatically with technological progress. Innovations on the technology of electronic devices led to a shorter usage and lifespan and thus boosted the generation of Waste Electrical and Electronic Equipment (WEEE). WEEE is one of the fastest growing waste streams, growing at 3 to 4% per year worldwide and is expected to reach more than 52 million tons per year by 2021. Currently, about 45 Mt of these wastes are estimated to arise worldwide, and the trend is rising (Baldé et al., 2017).

Jan 1, 2019