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By T. M. Chagwedera, A. E. Lewis, J. Chivavava

Eutectic freeze crystallisation is a novel separation technique that can be applied to treat brine solutions such as reverse osmosis retentates, which are often a mixture of different inorganic salts. The treatment of calcium sulphate-rich brine solutions through eutectic freeze crystallisation has resulted in gypsum scale formation on the walls of the crystallisers and ancillary equipment. In order to prevent gypsum scaling on equipment surfaces, it is essential to understand the mechanism of gypsum scaling on cold surfaces. This paper focused on the interaction between gypsum crystallisation in the bulk solution and scaling on the crystalliser walls in the presence of gypsum seeds. A cooled, U-shaped stainless-steel tube suspended in the saturated solution was employed as the scaling surface. Preliminary results showed that the scale layer was predominantly composed of needle-type and hexagonal prismatic crystals. The rate of scale deposition was highest during the first 24 hours, thereafter it decreased. A thin scale layer was observed to have coated the tube within the first hour of the experiment. Seeding, using reagent grade gypsum crystals, was effective in reducing scale layer formation through providing a surface for growth. The highest scale reduction, 81%, was realised at a seed loading of 0.50 g/L. At a high seed loading of 4.01 g/L, the seed material adhered to the tube. Keywords: Gypsum, eutectic freeze crystallization, seeding, scaling, cooling crystallisation

Jan 1, 2020

By D. H. Diering

Definition of mineral resources and reserves forms the basis for effective mine planning and reliable public reporting of mineral assets. Historically the mineral resource and reserves declaration process has been the domain of the geology and surveying disciplines, with the declaration of the reserves by the surveyor being based on the application of modifying factors to the declared resources available for mining. As part of an ongoing process to improve efficiency, reliability, and reproducibility of results, this approach has been revised and enhanced through the introduction of a revised process and reconciliation tools. The revised approach to reserve definition is based on the definition of scheduled resources, at an appropriate confidence estimate in the context of an approved business plan, over the anticipated life of the mineral asset being applied to define reserves. This planning and scheduling is developed, during the annual business planning process, by the mine planning department using tools such as CADSMine?. The scheduled area together with the application of revised modifying factors is tabulated in the BME (basic mine equation) and reflects the mine production plan over time. Simplification of the modifying factors to dilution and losses underpins the simple yet robust approach to improved definition of reserves in this process and in the basic resource to reserve equation (BR2RE). Dilution intrinsically affects grade but not metal content, whereas the losses reflect both the efficiency of mining and planning and are reflected in metal losses, area losses, or both. Reconciliation of the derived ?resource converted to reserve? area, (which is based on the business plan from CADSMine?), versus the ?resource available for mining?, (which is derived from Datamine?), underpins the robustness and auditability of the reserves declaration. This R&R accounting and reconciliation approach is transparent and facilitates interrogation of the logic and rationale of long-term business planning and project strategy. These numbers are processed and reported in the logic of the basic resource equation (BRE), which also addresses aspects such as white areas (future and historic), tail management, and partial extraction (non-scheduled pillars, etc.) in compliance with SAMREC definitions. Areas that do not have the necessary confidence and data support to be declared as resources find their space as pre-resource (outside the domain of public reporting), outlining existing potential for future extraction and reporting. Use of the BRE leads ultimately to a complete, refined accounting and reconciliation-oriented approach for all production entities. The revised resource and reserve process includes the discipline of mine planning as intrinsic to the definition and declaration of resources and reserves. Subsequent to the change in process, the resources and reserves have truly become the domain of the mineral resource management discipline. This paper defines the logic of the basic resource equations and outlines their application in the definition and reconciliation of mineral resources and reserves at Anglo American Platinum Limited.

Jan 1, 2012

By G. Akdogan, S. M. Bradshaw, M. I. Isaacs, P. Van Wyk

In the mineral processing industry, Ni-Cu-Fe-S converter matte is leached in order to remove base metals from a concentrate containing platinum group metals (PGMs). This paper investigates the atmospheric leaching process, in order to develop a better understanding of the leaching behaviour of the base metals; in particular Cu, Fe, Ni, and the PGMs in particular Ru and Ir with key process variables, acid concentration, copper concentration under oxidative leaching conditions. Higher initial acid concentration resulted in a higher copper, iron and nickel extractions, as well as higher leaching rates together with faster Cu, Ru, Ir precipitation occurring. On the other hand, a higher initial copper concentration resulted in more nickel but less iron being extracted. Keywords: PGM, converter matte, leaching, precipitation

Jan 1, 2020

By B. M. V. Baloyi, D. Mchabe, D. Chetty

South Africa accounts for the largest global manganese ore production share, primarily from its Kalahari Manganese Field deposit. Despite this, domestic smelting is beset by energy constraints, resulting in most ore being exported for smelting. Mintek is investigating energyefficient pathways for ore reduction, specifically undertaking prereduction tests to reduce energy consumption for manganese smelting. The present contribution considers the effect of methane, anthracite, and holding time, at a fixed temperature, on the extent of reduction of Mamatwan-type ore, primarily from a mineralogical perspective. In particular, the aim was to carburise the monoxide Mn phase to Mn carbide, as this is less energy intensive than producing metallic Mn from the monoxide. Based on thermogravimetric test results, the ore and products from three experiment sets were analysed using X-ray diffraction and scanning electron microscopy to assess the phases and textures present. The findings show that carburisation of manganese monoxide and its equivalents is most advanced under conditions of 8% anthracite, 10% methane, and 60 minutes of holding time, thus confirming with the thermogravimetric data. These results show promise for reducing energy consumption for Mn smelting in ferromanganese production.

Mar 4, 2025

By L Dyer, G. J. Wilkie, P. Walters, B Tadesse, L. Keeney

Grade Engineering® is a term trademarked by the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE) and includes five key levers for upgrading ores and rejecting waste prior to expensive downstream comminution and mineral processing. These five levers include natural deportment, induced deportment, bulk sorting, particle sorting and gravity separation. Over the past ten years, CRC ORE has progressed a range of technologies that exploit these levers from laboratory proof of concept through to large scale demonstration and validation. This paper details the work carried out by CRC ORE and Curtin University for assessing the amenability of an ore for its natural deportment and particle sorting attributes in an Integrated Screening and Particle Sorting (ISPS) Grade Engineering® process. ISPS is seen as a preferred method for Grade Engineering® as compared to individually operated unit operations as the benefits of each can be complementary. Furthermore, it is suggested that integrating the two levers has two important impacts: 1. Firstly, there is a risk that isolated particle sorting test results will be misinterpreted as being representative of the full sample without considering the mass balance impact of high-grade material that might have been lost in the fines fraction. This fine fraction will not be detected through the particle sorter. 2. Secondly, and potentially of more valuable impact, is that the opportunity may exist to upgrade the feed first through determining if there is a concentration of high grade to the fine (or coarse) fraction which can be separated through screening. Undertaking screening in the preparation stage of the particle sorting process will enable analysis and separation of the fine or coarse fractions of a rock mass. The result of this study provides the mining industry with an independent framework for undertaking an Order of Magnitude (ISPS) Grade Engineering® assessment on a range of constituent ore types. Keywords: Grade engineering, particle sorting, grade by size fractionation

Jan 1, 2020

By T. Oberthür

The Great Dyke of Zimbabwe constitutes the world?s second largest reserve of platinum group elements (PGE) after the Bushveld Complex in neighbouring South Africa. Within the Great Dyke, economic concentrations of PGE are restricted to sulphide disseminations of the Main Sulphide Zone (MSZ), which are currently mined at the Ngezi, Unki, and Mimosa mines. Near-surface oxidized MSZ ores have a large potential. Their total resources are in the range of ca. 160 ? 250 Mt; however, all previous attempts to extract the PGE from this ore type proved uneconomic due to low PGE recoveries (<< 50 per cent) achieved by conventional metallurgical methods. Within the ores of pristine, sulphide-bearing MSZ, the PGE are bimodally distributed. Platinum occurs mainly in the form of discrete platinum group mineral (PGM) grains (mainly bismuthotellurides, sulphides, and arsenides), whereas approximately 80 per cent of the Pd (and some Rh) is hosted in pentlandite. Within the oxidized MSZ ores, the PGE are polymodally distributed. Whereas arsenide- and sulphide-PGMs, making up ca. 25 per cent of the original Pt content of the ore, largely remain stable (relict PGMs), the remaining PGMs are disintegrated. The base metal sulphides are destroyed, partly releasing their base metal and PGE contents, and are replaced by iron oxides or hydroxides. Unspecified amounts of the PGE are redistributed and either form secondary PGMs, are found in chemically and mineralogically ill-defined (Pt/Pd)-oxides or hydroxides, or in iron-hydroxides, Mn?Co-hydroxides, and in secondary silicates. The problematic processing of oxidized MSZ ores is attributable to their complex nature and polymodal distribution of the PGE, prohibiting a significant upgrading of the ores by conventional metallurgical methods. Therefore, only bulk leaching methods are viable for ore treatment, and novel metallurgical methods have to be developed for the processing of these ores. Our ongoing work aims at locating the PGE in their mineralogical form in order to understand the mineralogical balance of the PGE in the ores and thereby facilitate the evaluation of metallurgical options for their recovery. A short overview on options and recent advances regarding the recovery of the PGE from oxidized ores is given.

Jan 1, 2012

By W. Newcomen, G. Dick

"Effective management and mitigation of pit slope instability in open pit mines begins with a comprehensive slope monitoring programme. The ability to differentiate between non-critical pit wall movements due to rebound or relaxation of the excavated slopes and movements that may be indicative of slope failure is important for maintaining a safe working environment and maximizing production. Slope failure prediction methods using velocity, acceleration, and strain criteria have been introduced and put into practice over the past few decades. Forty-eight slope failures with surface monitoring data are presented and assessed using the strain-based failure prediction approach, with consideration of the quality of the rock mass and the potential failure mechanism. The results indicate that the strain-based approach can be used to provide general guidance regarding strain thresholds for pit walls for a variety of failure modes in diverse geological environments. The advantages and potential drawbacks of the strain-based and other slope failure prediction methods are discussed. The importance of implementing a pit slope monitoring and performance evaluation system early in mine development is also emphasized. IntroductionThe successful prediction of the Manefay Slide pit slope failure at Bingham Canyon at 9:30 am on 10 April 2013 (Engineering and Mining Journal, 2014) highlighted the importance of having a comprehensive slope monitoring system that provides an accurate prediction of the time of failure of an open pit slope. Using most of the geotechnical monitoring tools available, the time of the failure was predicted within hours and equipment and personnel were evacuated from the pit well in advance of the failure. From a time to slope failure perspective, the monitoring system in place was a success.There are two general groups interested in monitoring pit walls, with slightly different objectives in mind when the monitoring system is being set up. There are those at the mine site that have to implement the pit slope design, monitoring protocols, and the action response plans, and there are those designing the slopes (often consultants) who regularly visit the mine but may not be responsible for the day-to-day activities. was a success.There are two general groups interested in monitoring pit walls, with slightly different objectives in mind when the monitoring system is being set up. There are those at the mine site that have to implement the pit slope design, monitoring protocols, and the action response plans, and there are those designing the slopes (often consultants) who regularly visit the mine but may not be responsible for the day-to-day activities."

Jan 1, 2016

By N. V. Nemchinova, A. A. Kozlov, A. V. Epiforov

The gold dissolution in sulfuric acid media during industrial oxidative leaching test of sulfide gold-copper flotation concentrates has been achieved. The reason for this was using technological water containing thiocyanates and cyanides, which can dissolve gold under these conditions. The carbon in column (CIC) process for gold recovery from these solutions was proposed. However, significant amounts of copper and iron were adsorbed onto the carbon during CIC technology industrial tests. This resulted in a decrease of the gold content in the loaded carbon up to 0.5 kg/t. Further development of the technology was conducted by optimisation of gold and impurities stripping and implementation of carbon reactivation. It was shown, that the copper extraction from the loaded carbon during cyanide treatment was about 95%. The copper content in the stripped carbon after cyanide treatment was 1.76 kg/t. The gold recovery during high-pressure elution by caustic solution was 98%. The hydrochloric acidic treatment with thermal pre-treatment (reactivation) for removing iron and calcium from gold-free carbon was proposed. In this case, the iron and calcium extractions from carbon were 40-45 and 50-55% respectively. These tests showed that for carbon recycling the sequence operations of ‘cyanide treatment, gold elution, thermal pre-treatment, hydrochloric acidic treatment’ can be used. Keywords: Thiocyanate leaching, recovery of gold, carbon adsorption, gold elution, copper stripping, thermal reactivation of carbon, activated carbon, carbon-in-column

Jan 1, 2020

By P. de A. Barbosa, M. G. Bergerman, E. da Fonseca

Located in the state of Pará, Brazil, the Sossego copper and gold mine consists of a heterogeneous geological deposit. Its complexity derives from the hydrothermal alteration, the ore-forming event, which modified the host rocks, such as granite, and metamorphosed volcanic rocks into several mineral assemblages. Different mineral assemblages have led to differences in abrasiveness. A few Bond abrasion tests conducted during the mine feasibility study did not provide a robust abrasiveness database, thus the variation of physical properties for some mineralisation host rocks was not possible. Although several test methods may be used to determine ore abrasiveness, the Bond method is the one most commonly used in the mining industry. Despite being simple to carry out, this test method has certain limitations as to particle size and the amount of ore sample required, which often makes it difficult or even impossible to apply in the early stages of a project and in geometallurgical studies. The Laboratoire Central des Ponts et Chaussées (LCPC) test may provide an alternative, as it requires a smaller amount of fine-grained material. This study aimed to provide data on wear properties of various ore types from Sossego mine using the LCPC method. It included validation for 40 different ore samples using the Bond test as a benchmark. The results showed good correlation, indicating it may be possible to use the LCPC test as an alternative to the Bond abrasion test. A high abrasiveness index was found for acid metavolcanic rock, confirming the results observed in Sossego mill’s operating database, pointing to a mineralogical drive to amorphous quartz. Keywords: Abrasiveness, geometallurgy, copper ore, Bond abrasion test, LCPC

Jan 1, 2020

By D. Saramak, T. Gawenda, A. Stempkowska, Z. Naziemiec

The aim of the paper is to discuss the possibility of producing aggregates with an increased content of regular particles, as well as to present a method of aggregate production which has not previously been used in the industry. Traditional aggregate production circuits require the application of three or four grinding stages (depending on the particle size of the feed), but for fine particle fractions of aggregates, irregular grains occur on average with a content of 10%. The innovative technological circuit can produce the aggregates with the content below 3%, even in a single- or two-stage crushing circuit. Downstream jig beneficiation of such prepared material results in higher separation sharpness, lower probable error index (Ep) and imperfection (I). Keywords: Aggregate production, jig beneficiation, mineral processing, raw materials

Jan 1, 2020

By S. Langea, H. Lieberwirth

Impact crushers are common machines in comminution plants. Their high size-reduction ratio and relatively simple design, make them a preferred tool even when subjected to harsh wear, and producing a large quantity of fines in some applications. Until now the alignment of the operational parameters was an operator’s responsibility. Due to the random process characteristic this is mostly done based on empirical values and sensor data, such as power consumption. This paper describes a new approach for online process monitoring of the horizontal-shaft-impact crusher. The application of robust, low-cost acceleration sensors enables the permanent observation of the process characteristics. The operational and evaluation methods are determined on the basis of experiments. Subsequently the recorded measurements are analysed in regards of throughput, rotational speed and product particle size distribution. Occurring signal characteristics are described based on physical and technical principles. The measured data of the acceleration sensors at varying operation conditions provide insight in the course of process. The accurate utilisation yields the determination of the preferential process conditions providing the best balance between the pros and cons of an impact crusher. Both the experimental method and the data processing is discussed from a scientific perspective, displaying a completely new approach for the operation of impact crushers. Keywords: Impact crusher, acceleration sensors, data processing, particle size

Jan 1, 2020

By O. T. Konina, V. A. Masloboev, A. V. Svetlov, E. A. Krasavtseva, D. V. Makarov, A. A. Goryachev

Dusting phenomena have been examined at the tailings storage facility of Apatit JSC Kirovsk, a mining operation located in the far north of the Russian Federation. The material composition of the tailings was identified. Existing dust suppression methods were examined. Field observations were undertaken and official data was obtained from the Murmansk Administration for Hydrometeorology and Environmental Monitoring, and analysed. A database was built for forecasting dusting according to critical scenarios in order to estimate the peak MPCs of suspended solids in the atmospheric air. Mitigation measures were formulated and recommended to the mining operation. Keywords: Mineral dust particles, apatite-nepheline ore concentration tailings, suspended solids MPC, climate change

Jan 1, 2020

By A. Buncombe

In March 1984, two years&apos; work by senior metallurgical personnel from the six major mining groups culminated in the formation of the Mine Metallurgical Managers&apos; Association of South Africa. This Association has joined a group of specialist Associations operating within the South African mining industry whose aims are to uphold the standards and promote the interests of their various professions.

Jan 1, 1987

By NIM REPORTS

Notices CONFRRENCE ON COMPUTRRS IN ENGINEERING The above Conference, which is being organized by the Electrical and Electronics Board of the Institution of Engineer!!, Australia, ill to be held in Sydney on 16th and 17th May, 1974. It is being planned in conjunction with the Sixth Australian Computer Conference and will be held during the week immediately preceding the latter. NIM REPORTS Report No. 1495 A method for the determination of ekmental sulphur on the surface of sulphide minerals. Report No. 1500 The chromatographic separation and determination of nobk metals in matte-leach residues. Report No. 1505 The production of the refractory aluminium saicates, with special refererence to South Africa. Report No. 1517 Computer-controlled flotation plants in Canada and Finland. Report No. 1526 Heat of solution as a control of aqueous-ammonia concentration. Report No. 1529 South African costs of equipment for the metallurgical industry (197).

Jan 9, 1973

By O. K. H. Sheff

An editorial in the April 1990 edition of Mining Magazine is worth a wider audience in South Africa, particularly as the SAIMM enters its own centenary decade and the process of change in the minerals industry world-wide makes increasing demands on the professionalism of its leaders. The editorial considers the changing status of engineers, who up to the 1880s had been held in high regard by society. Alumina and bauxite Economists forecast a slower economic growth rate in 1990, but expect continued increase in demand for aluminum at a 3 per cent annual rate during the decade. Structural and numerical analysis Struceng & Femcad (structural analysis and finiteelement method) is a conference and exhibition that is to be held in Grenoble (France) on 17th and 18th October, 1990. It is sponsored by the Institute for Industrial Technology Transfer (ITT-International).

Jan 1, 1990

By A. W. S. Schumann

A. W. S. Schumann The first reason for todays success lies in the very high standard which was set by our speakers today and I think that we owe a very special vote of thanks to Messrs P. M. C. Wilson, A. A. Oakes, M. J. Deats, A. C. Coetzee, R. E. Burnton and J. G. Ferguson. This, however, cannot account for the fact that there was a tremendous response even before anyone knew who was going to speak or what they were going to speak about. I suggest that the response was enthusiastic because people expected a more informal gathering with a greater opportunity for feedback, for an exchange of views and for questions and answers. The very popularity of the idea has defeated its own ends to some extent. This gathering is too big and many people must have been left with questions unanswered. Possibly one should arrange for a number of meeting places-there are many in the Chamber and the surrounding mining houses-and then have separate meetings in the morning with joint reporting session in the afternoon. Alternatively, we could have a symposium after the colloquium, using Webster&apos;s definition of a symposium as as &apos;a drinking party of merry fellows&apos;. We all know that it is easy to discuss mining into the small hours. Obviously one cannot summarise todays papers and discussions, but I would like to make a few comments on technical matters and after that I would like to speak for a moment about what I see as major trends or tendencies which arise from discussions of this nature. Regarding the question of placing a village on a mine or away from a mine, I would mention that there is quite a body of literature on the adverse sociological effects on the development of children in any community in which the great majority of parents share the same occupation. It is something to be avoided if possible. We discussed the concept of the moving stockpile. If this is proved to be successful, it could save a considerable amount of money for Escom who could then avoid the construction of very large and costly staithes which are now regarded as parts of power stations. One does not see why both a moving stockpile and a staith should be necessary. By the way, speaking of Escom, I see that Mr Bob Scott is here; he has stopped pulling my leg by saying that we sell stone to Escom; perhaps someone has told him that if this is true, it must be the cheapest stone you can buy in this country. My next point relates to the use of epidiascope. It struck me again that this instrument which provides a visual image to accompany your message, can be very effective if it is properly used. These papers speak of a great deal of hard work which went into their preparation, and one really feels that the authors should have taken a few minutes more to prepare their drawings specifically for the epidiascope. There should be nothing on the drawing which is not necessary to illustrate a particular point and there should be nothing on the drawing which is not visible from the back of the hall. In particular, if one cannot read the figures along the sides, then one

AFRICAN NATIONAL COMMITTEE ON TUNNELLING In 1970, the South African Institution of Civil Engineers, the South African Institute of Mining and Metallurgy, the South African Institute of Mechanical Engineers, and the Geological Society of South Africa held an international conference on tunnelling, known as Tuncon 1970. SUID-AFRIKAANSE NASIONALE TONNELBOUKOMITEE In 1970 het die Suid-Afrikaanse Instituut van Siviele Ingenieurs, die Suid-Afrikaanse Instituut vir Mynbou en Metallurgie, die Suid-Afrikaanse Instituut van Meganiese Ingenieurs en Die Geologiese Vereniging van Suid-Afrika &apos;n internasionale konferensie in verband met tonnelbou gehou, wat bekend gestaan het as Tonkon 1970.

Jan 5, 1974

By T. B. Beeton

In view of the limited reserves of good-quality coking coals in South Africa, Iscor has been involved in direct reduction since the middle sixties. Since the early seventies, its interest in direct reduction was stimulated further by a swing towards&apos; continuous casting, which, in turn, contributed to a shortage of the scrap supply for electric-arc-furnace (EAP) steelmaking. Rock engineering The First International Conference-Rock Enginet:ring and Excavation in an Urban Environmentorganized by The Institution of Mining and Metallurgy and the Hong Kong Section of the Institution, in association with the Hong Kong Institution of Engineers, will be held in Hong Kong from 23rd to 28th February, 1986. SPOTLIGHT on Gold Fields National Engineering Awards For the Gold Fields Foundation National Engineering Awards, each university affiliated to the South African Federation of University Engineering Students (S.A.F.U.E.S.) selected a candidate who, in their opinion, presented the most outstanding design project in their final year during 1984.

Jan 1, 1985

By C. A. Green, M. A. T. Cocquerel, R. T. Gates

"Engineering studies by Selection Trust, Limited, initially in connection with the development of a copper and nickel deposit for Bamangwato Concessions, Limited, and subsequently for several other clients, have required a large number of metallurgical design calculations. The flash smelting process, developed by Outokumpu Oy in Finland, has been selected as the most suitable method for these projects and the computer programs described in this paper have been developed to facilitate the computation.The data required by the programs arc the chemical and mineralogical analyses of the concentrate, gangue and flux materials and the specification of possible fuels. The required grade of furnace matte is set as the main design parameter and the programs calculate detailed heat and material balances for the smelting process."

Jan 1, 2014

"Chairman: Professor J. de V. Lambrechts Rapporteur: Mr R. HempPapers:Computer-aided design of a flash smelting installation by M. A. T. Cocquerel, R. T. Gates and L. A. GreenPlanning of mine ventilation by E. U. Reuther and A. DohrnenCoal mine ventilation systems in the U.S.A. by R. Stefanko and R. V. Ramani Heat flow models in ventilation planning by A. J. Dickson and A. M. StarfieldThe first of the papers in the session dealt with a flash smelter installation, while the remaining three papers dealt with mine ventilation. In view of this the Chairman proposed that the paper on flash smelting be introduced and discussed first, after which the remaining three papers would be introduced followed by discussion on all three.Dr Cocquerel, who presented the first paper, used some typical flow diagrams to illustrate the process and stated that the program considered only steady-state operations and did not take into account the dynamical changes. Subjective judgment was necessary for the preparation of input data and some degree of user appreciation was required.Dr Cocquerel said that no work bad yet been done on an optimization program, but that this was being considered. Such a program would require a large amount of physical and chemical data which were not yet available. The variables to be optimized were the energy and material consumptions and the loss of metal in the slag.The Chairman opened the discussion by asking Dr Cocquerel if he could give a brief description of the flash smelting process for the benefit of those not familiar with the subject. Dr Coquerel replied that in the Outokumpu process con¬centrates were injected directly into the furnace, and that the process was somewhat analogous to flash distillation or evaporation processes, but was perhaps closer to the burning of pulverized fuel.The process had two distinct advantages. First, the heat evolved in the smelting reaction was used to heat the furnace, which resulted in less fuel consumption, and, second, the effluent gases were cheaper to treat than the effluent gases from other pyrometallurgical processes. This was important particularly in view of the current interest in pollution problems.Mr P. Marais thought that the authors had done themselves an injustice by not including details of the very complex processes taking place in the furnace."

Jan 1, 2014