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By Benoit Clermont, Jan Lux

"Magotteaux and Anglo Platinum started a co-operation program with the main aim of establishing the optimum milling configuration measured in terms of throughput, fineness and energy consumption.For this purpose, a fully instrumented pilot milling plant, supplied by Magotteaux (Pty) Ltd, and equipped with a 0.9 x 1.0 m ball mill, was erected at Frank concentrator (Merensky Pt ore). The primary ball mills at Frank concentrator were surveyed in order to set the conditions for the base case. This data was then replicated in the pilot mill under the same configuration. Thereafter, a series of different parameters were varied in order to attempt to optimize the milling system.Only grate versus overflow discharge and open versus closed circuit will be discussed in this paper.It should be noted that this paper does not attempt to give a universal solution as to what milling configuration is optimum in all cases. The conclusions apply for this particular case and probably most others, but it would be advisable to consider each case on its own.CONCLUSION• Overflow versus grate dischargeAn overflow mill has a “pool” of slurry around the toe of the ball charge, which creates a counter lever to the ball charge. This will reduce the absorbed power in the range of 10-15% (depending on the case) and will consequently result in a coarser grind. The tests found a 4% gain in grinding efficiency (Wio) with an overflow mill but this is probably not significant.This lower absorbed power and coarser grind can be counteracted by increasing the ball charge (if below maximum) and/or by increasing the mill volume when removing the grate discharge (a typical grate takes up about 300mm of the mill length).• Open versus closed circuit"

Jan 1, 2003

By A. F. Raschenko, Y. A. Golodcov, V. V. Elshin

"The autoclave noble metal desorption in apparatuses with a dense stationary sorbent layer is perspective for the technology of sorption gold and silver extraction from solutions and pulps by carbon sorbents. The study of the mechanism and optimization of the autoclave desorption process involve some difficulties. To overcome them it is necessary to use mathematical and quantum-chemical modelling. The given paper deals with a mathematical model for the dynamics of gold and silver desorption from active carbons by alkali solutions based on the physical-chemical notions of the process. The kinetics and the mechanism of the process were investigated using the mathematical model for gold and silver desorption.The calculation of the efficient mass-transfer coefficient (ße) for various initial and intermediate noble metal concentrations in carbon (Cy) made it possible to find that the dependence of ße on Cy in case of gold desoprtion shows a clear extreme character. The value of the initial metal concentration in carbon therewith does not influence the character of the curve the inflection point of which is changed essentially at elevated process temperatures only. The revealed characteristic property, in the author's opinion can only be indicative of the change in the mechanism of gold desorption under autoclave desorption conditions. The assumed [Au(CN)(OH)]- type intermediate that has a higher diffusion coefficient in comparison with the adsorbed complex [Au(CN)2]- can be considered as an intermediate compound in the process of gold desorption."

Jan 1, 2003

By L. A. Vaisberg

"Crushing and grinding are the two most common industrial processes. These processes consume nearly 20 per cent of the entire electric power produced worldwide. This enormous amount of electric power consumed results from the fact that modern crushing and grinding machines employ the processes first introduced by the prehistoric man, namely those of compression, impact, attrition, and cutting. The material thus handled decomposes indiscriminately, and almost completely ignoring the microscopic cracks and other defects of its structure. Apart from the irrational use of the power, the crushing and grinding processes currently in use result in irretrievable loss of useful components or else in a substantial deterioration of the final products obtained, all as a result of incomplete grinding or, reversely, of overgrinding, palletizing, or fracture of particles.The principal type of equipment that has almost universally been used all over the world for more than 150 years for crushing both natural and synthetic minerals comprises unbalanced jaw and cone crushers. The driving element of crushing bodies in these machines is an unbalanced weight, which transfers the crushing body, allowing it to squeeze the material within the eccentricity value only. The maximum reduction ratio achieved by such a drive is 5, which is due to the rigid kinematic arrangement of the crusher, its dynamic unbalance, and the impossibility of increasing the number of impacts on the material being crushed. Moreover, conventional machines cannot cope with super hard materials, and their mechanism is vulnerable to damage by uncrushable objects.On the basis of fundamental research into the theories of solid body and vibration, OAO Mekhanobr- Tekhnika have developed a range of vibrating jaw and cone inertia crushers that make a reduction ratio of 30 feasible in an open-circuit operation with the reduction ratio monitored within a wide range. In these crushers, the eccentric drive is replaced with a vibrating one. In this way the rigid kinematic drive became dynamic, thus allowing pieces of material to be crushed in a thick layer due to the effect of their bumping into each other, and with the amplitude changing automatically. This results in a number of advantages as compared with conventional crushers:"

Jan 1, 2003

By M. Brozek, W. Pawlos

"The separation of raw materials in the separator with ferromagnetic liquid occurs due to differences in magnetic and gravitational properties of respective components in relation to each other and to the liquid. In the separator with wedge-shaped pole shoes and the working space axis inclined at a certain angle to the horizontal direction, the paths of grain movement at fixed separation conditions depend on its physical properties. Due to this, the levels of grains outlet from the separator working space are differentiated according to differences in their physical properties. The distance between the levels of outlets from the separator working chamber depends on magnetization of the liquid which is proportional to the liquid density, on the magnetic field intensity and the inclination angle of the separator working passage to the horizontal axis. The separation accuracy is higher the larger is the distance between the outlet levels.The paper will present the methods of visual observation and recording of movement paths of coal grains of different physical properties in the paramagnetic liquid which was the water solution of manganese chloride. The paths were recorded with a video camera in the working chamber by means of a specially constructed device, acting as a periscope, which were then transformed into digital images. Experimental movement paths were confronted to the paths obtained in a theoretical way by means of solving differential equations of movement by a numerical method, achieving good compatibility of experimental and theoretical results. The equations of movement were solved with taking into consideration the drag force, expressed by formula for laminar and dynamic conditions of motion.The course of the path of grain movement depends on grain and liquid physical properties, magnetic field intensity and inclination angle of the working space to the horizontal direction. The two latter parameters can continuously control the process of separation."

Jan 1, 2003

By M. Barsky, A. Govorov, E. Barsky

A study was conducted to determine the structure and lifting capacity of a two-phase stream in a vertical pipe at different distances from the point of introduction of the material into the instrument. Stream velocity was set at 2.8, 4.0, 4.8, 5.6 and 6.25 m/sec to ensure separation regimes. It was found that the llifting capacity of the two-phase stream exceeded that of pure air by a factor of three or more, and that in a turbulent regime the velocity curve displayed marked deformation, becoming more rounded and tending towards a parabola. The following formula was obtained for entrainment of a given size fraction under turbulent, laminar and transitional particle flow regimes:

Jan 1, 2003

By Rogerio C. Guimarães, Antonio E. C. Peres

The production of phosphate concentrates (phosphate rock) from slimes represents a challenge to the phosphate industry worldwide. In Brazil, this challenge is particularly relevant due to the consistently low P2O5 grades and the igneous origin. The Brazilian phosphate deposits are made up mainly of apatite from alkaline chimneys, representing 80% of the Brazilian reserves; phosphorite deposits contribute 18% and the other sources (guano, phosphorous bauxite, and apatite from veins) reach 2%. The Brazilian industry beneficiates phosphate ores that are mineralogically more complex than those treated elsewhere. The low apatite grade, inherent to the igneous Brazilian ores, added to the mineralogical complexity due to the weathering of the rocks, has represented a permanent challenge to the Brazilian process engineers. The total measured, indicated and inferred reserves reach 3.2 million tonnes of ore with average grade 11% P2O5. The development of local technology for phosphate beneficiation started in the 1960’s. The first industrial experiences of producing phosphate rock from slimes (-44µm or -325#) fraction started at Arafertil, currently Bunge Fertilizantes SA, in Araxá, in the 1980’s. This production corresponds, nowadays, to 35% of the total production of concentrates in the company (830,000t/year) in a circuit consisting of desliming in 40mm microcyclones and concentration in flotation columns, corn starch and fatty acids being utilised as reagents. The performance of slimes flotation and the process control, at Bunge´s concentrator, were improved after the introduction of column flotation technology, in the first half of the nineties. The column flotation technology for slimes recovery was expanded to other Brazilian concentrators still in the nineties: Ultrafértil (Catalão – GO), Bunge (Cajati – SP), Fosfértil (Tapira – MG) and Copebrás (Catalão – GO). At present the Brazilian production of phosphate rock is approximately 4.5Mt/year, with a strong trend for a market increase. Genuinely Brazilian technology is utilised for the processing of slimes, the concentrates representing 11 to 13% of the overall production. The production of apatite concentrates from slimes was relevant to increase phosphate recovery and reduce costs, contributing to the growth of the fertilisers industry.

Jan 1, 2003

By ?. ?. Zimin, B. A. Kutlin, X. Baddamsuren

"The ore features of Mongolian fluorspar deposits are shown in the paper. The possibilities of the technological of ore processing on the Bor-Undur combine scheme improvement are analyzed there. Some recommendations are done for scheme development: spare output technologies, the usage large-sized ore separation, flotation by columnar flotation cells, leaching and concentrate agglomeration.New evaluation and usage of mineral sources approach was developed for Mongolian fluoride ores. The conception allows using maximally available mineral resources for getting of metallurgical and acid fluoride concentrates while mining and technological processes: mining (as well as quarrying) -storing, blending-crushing, grinding-combined processing methods-metallurgical using preparation It has been established mining and processing technological schemes should include:• spare blasting technologies providing minimum effect on fluorite crystals which follows ore selective excavation;• large-sized ore separation methods resulted in maximum recovery for these operations in respect to metallurgical fluorite concentrates;• grinding and flotation regimes providing high-quality flotation concentrates getting for their usein chemical industry;• fluorite concentrates agglomeration technologies for providing ability of their use in metallurgical and cement industriesThe results of industrial usage of jugging machines, columnar and pneumomechanical flotation machines for fluospar dressing.The technological approaches implementation in “Bor-Undur” plant maintenance within 1993-2002 years leaded to:• change plant status from just flotation one to gravitational-flotation characterized by technological process stages which are traditional for metallurgical industry and plant capacity increase from 400 to 600 thousand tones of treatment ore as well as concentrate production increase from 120 to 150-170 thousand tones including 120-140 thousand tones of acid grade concentrates with 97% CaF2 ."

Jan 1, 2003

By Stephen Gay, Dewetia Latti

"When improving a plant a mineral processing engineer would like to know the mineral composition distribution. In order to assess this distribution in particles, as compared to the corresponding distribution in particle sections, a procedure needs to be applied to the observed particle sections. Such a procedure is called a stereological correction. There exists many stereological correction procedures, but one group of such procedures is based on using those stereological equations that do not require making assumptions regarding particle shape or texture. These equations are called geometric probability equations.Davy derived a geometric probability equation to estimate the covariance of mineral composition distributions for particles from both particle sections and linear intercepts. This covariance can be used to measure the variance of the particle composition distribution of each mineral. The equation as presented by Davy requires textural information; however the equation was modified by Gay to be more directly applied to particle sections and linear intercepts. The variance obtained from applying this equation is fundamental to the binary stereological correction procedures developed by Gay and his colleagues; the covariance is fundamental to the multiphase stereological correction.Thus far, validation of both the binary and multiphase stereological correction has been achieved using numerical simulation. This paper shall present results comparing the covariance (and variance) estimates from Gay’s equation with actual three-dimensional information obtained from serially sectioning particles. This involved mounting a set of particles and continuously sectioning all particles uniformly so that the three dimensional structure of the particles could be obtained.The mineralogical data to which the equations described above were applied were derived from two individual size fractions from a hard-rock titanium deposit. The deposit contains a range of minerals and of mineral textures and the two size fractions selected were:"

Jan 1, 2003

By M. Salas, L. Rolf, H. Z. Kuyumcu

"Industrial use of abrasive stress takes place in the area of fine grinding and in order to clean surface contaminated soil particles. Also, at many mechanical operations abrasion emerge as an unintended side effect. At the Institute for Raw and Waste Material Processing at the Technical University of Berlin systematic investigations are carried out, to further the knowledge regarding the dependence of abrasion process on material properties and stress mechanisms as a basis for design and optimisation of the process or for its avoidance. Aim was the mathematical description of the abrasion process running with a single particle stress. For the purpose of investigations an agitation cell was used. Limestone served as material.In the presented work the influence of particle diameter, particle shape and collision energy on the mass and particle size distribution of abrasion debris was studied. The surface geometry of the particle was characterised by the particle shape factor ?x and the particle diameter dp. The particle shape factor ?x stays in direct relation with the abrasion degree x, and can be substituted by a mathematical function of x.Physically the particle shape factor ?x can be interpreted as a proportion of abrasive stresses splitting up complete crystals and crystal fragments. These two different mechanisms depend on different ratios of curvature of the surface of the stressed particle. The abrasive stress of strongly curved surface areas leads to separation of complete crystals. The abrasive stress of weakly curved surface areas leads to separation of crystals fragments. Accordingly the mass of wear mAb and median diameter of the abrasion debris d50 are different. The derived mathematical relations consider this behaviour by the particle shape factor ?x , which represents the ratio of the mixture of both stress mechanisms. The dependence of the particle shape factor ?x on the abrasion degree x with an exponent approximately to 2/3 points out that the particle shape factor ?x represents a surface area relation."

Jan 1, 2003

By Robin J. Batterham

Alumina demand is steadily climbing around the world and is likely to continue to do so for many years. In such a commodity industry, the question arises as to what effort should be expended on innovation, given that for an individual company, the drivers of change are cost and quality as the market demand is essentially assured. This is of course a long-term view. The current conditions are less attractive. In this presentation, we review the broad issues that are considered targets for collaborative development by the industry as recently updated in the alumina industry roadmap published by the International Aluminium Institute in 2010. While they cover areas such as ?mine rehabilitation, residue management and use, alumina production from high sulfur bauxite, bauxite beneficiation, energy efficiency and alternative technologies for alkali and alumina recovery from bauxite residues,? it must be remembered that each refinery is different in terms of the feed material and the circumstances of waste disposal. Of particular interest is the more competitive area of breakthrough technologies. In the presentation, we will consider a range of opportunities that could transform the industry, from relatively near term possibilities such as bauxite activation through possibilities to eliminate crystallization as currently practiced to complete alternatives, such as the use of hyperaccumulating plants. Against this optimism, some of the realities that hold back breakthrough innovation will be presented for discussion.

Sep 1, 2012

By Jochen Petersen, David G. Dixon

"Although heap leaching may be perceived as a somewhat low-tech route for the extraction of low-grade minerals, the underlying physical, chemical and biological processes are in fact extremely complex. There has been increased interest in heap leaching of sulphide minerals in recent years with the advent of controlled bio-heap leaching, and the need to mine more marginal ore deposits.A detailed investigation into the dynamics of heap leach processes has provided much insight into the underlying complexities, and has led to the development of a sophisticated modelling tool, HeapSim. Some of the sub-processes that are modelled include mineral kinetics, particle size effects, bacterial growth, oxidation and adsorption, gas adsorption, pore diffusion, bulk advection, gas balance and heat conservation. The interplay of these various sub-processes is illustrated in the paper.Two case studies are presented which illustrate specific features of the model for different applications and how these have helped to identify key areas of concern. The first is focussed on chalcocite heap bioleaching, which shows that by nature of the reaction the process is strongly dependent on the initial supply of acid to the mineral site. In heaps this acid supply can be severely limited by the rate of diffusion from channels of flowing solution into stagnant zones of the heap, whereas in narrow-bore laboratory columns this effect is not observed."

Jan 1, 2003

By N. Raeis Hosseiny, S. H. Bassir

"Chador-Malu iron ore is one of the most important iron mines of Iran.About 98 percent of Fe in the ore is in shape of Magnetite, Hematite, Martite, aqua oxide of Iron and the other irons are with ferrous silicates, actinolite, cholorite and ferrous dolomites. 1% of Fe has replaced in pyrite. The phosphor distribution in the ore is non-hemogenous and its average in the whole of the deposit is 94%. It is in shape of Apatite.This mine contains considerable phosphor, which makes it useless for metallurgical uses. At this mine the phosphor is reduced in the iron ore at two steps. At the first step, magnetic part of the ore is separated from the gangues and phosphors by magnetic separator. At the second step, the ore is enriched by the flotation methods. Experimental flotation methods to obtain the optimum conditions are as follows:• Effect of Starch as Hematite depressant with ATRAC as Apatite collector• Effect of Sodium silicate as Hematite depressant with ATRAC as Apatite collector• Effect of ASAM as Apatite collector with Sodium silicate as Hematite depressant• Effect of ATRAC (BEROL) as Apatite collector with Sodium silicate as Hematite depressant• Effect of ASAM & ATRAC mixture as Apatite collector with Sodium silicate as Hematite depressant• Effect of Kcarbonate as pH-modifier• Final test to Optimize pH, Collector, DepressantAt this research we have found the optimum circumstance of the flotation of Chador-Malu iron ore in order to decreasing phosphors of iron oxide and floating of Apatite to make pure Hematite.To reach the optimum conditions, some tests were done with different amounts of pH, collector and depressant. The results are as follows:"

Jan 1, 2003

By Máximo Pérez, Julio C. Videla, Rosa Dzioba

"This paper reports the hydrometallurgical treatment of gravity concentrates of gold samples and outcrops associated with graphite ores obtained from:• flotation tailings of crystalline graphite minerals• outcrop samples of graphitic rock associated with auriferous minerals and free gold located in the Villa Union district and surrounding areas - La Rioja Province - Argentina.Previous studies of the flotation potential of crystalline graphite minerals failed to consider the presence of noble metals.The samples represent a mineralized zone of crystalline graphite which is distributed in different formations with a NE - SW trend in Maz, Punta Colorada and Las Ramaditas hills, covering an area of about 300 square kilometers."

Jan 1, 2003

By Hermann Wotruba, Lars Weitkämper

"Dry coal dressing was popular during the 1950’s and 60’s in many parts of the world. The devices mainly used were air jigs and air tables.The increase in ash and moisture content of run-of-mine coals due to the wide advanced mechanisation of mining methods during and after this period led to that pneumatic devices being unable to treat run-of mine coals with the desired efficiency. Since the 1960’s almost all new coal preparation plants have been based on wet processes that are highly efficient in terms of coal recovery and their ability to handle damp and sticky run-of-mine coals. (Frankland, 1995)However, water is becoming increasingly costly and the disposal of fine products, containing most of the water, is an environmental concern. There would be significant cost savings and a lower total energy consumption if coal could be cleaned dry. Efficient dry coal treatment would be an interesting solution in desert, arid or cold areas.In Germany one dry coal dressing plant is in operation. This is the last operating dry coal dressing plant existing in Europe. The actual technical standard of dry coal dressing has been analysed during test-work and sampling in this plant (Saar Region in Germany). The process and the advantages and disadvantages are presented. The plants problems are low efficiency in the fine fraction –6 mm and the coarse fraction +30 mm and a low overall throughput as well as the lack of an automatic process control system. The separation results in the medium size fractions between +6 and -30 mm are excellent"

Jan 1, 2003

By Xie Jiyuan, Hu Yuehua, Yang Songrong, Zhu Zhansheng, Qiu Guanzhou

"By the end of 2000, the first bio-oxidation plant in China that designed by ENFI come successfully into commercial operation in Yantai Gold Smeltery. Its capacity is 50t/d of refractory gold ore concentrate. After the extension, the capacity of bio-oxidation plant reached 80t/d of refractory gold ore concentrate at end of 2001.The refractory gold ore concentrate treated is from different gold mines. After proportionate feeding, the feed typically consists of Au (52.7g/t), S (24.42%), As (3.58%).The bacterial culture used in the bio-oxidation circuit is taken from a mine in south of China, and has been grown over 20 years on a variety of sulfide concentrates in a laboratory of mineral processing, and has shown to be adaptive to growth in a high concentrations of arsenic. It is a mixture of mesophilic microorganisms. The nutrients used in the bio-oxidation process are (NH4)2SO4, KH2PO4, KOH.Before feeding to bio-oxidation circuit, the concentrate would be milled to minus 43µm. The biooxidation product is fed to solid/liquid separation system that consists of a thickener and two press filters, solid from the system is fed to CCD circuit, liquid from the system is fed to neutralization area. The neutralized product is fed to another solid/liquid separation system, and the solid from the system is disposed of on a wasted quarry pit, the liquid from the system is returned to bio-oxidation circuit for reusing."

Jan 1, 2003

By Takashi Furuyama, Sukeyuki Mori, Abel Bissombolo

"In flotation practice, a good recovery of minerals largely depends on the degree to which the valuable minerals have been liberated from the associated gangue during the grinding process. Therefore, a regular measurement of the degree of liberation can provide data for the assessment of the quality of separation and predicts the effect of changes in the grinding-classifying circuit on flotation process. Generally, the standard procedure for measuring the degree of liberation requires the preparation of polished sections - a time consuming operation that also has the disadvantage of providing an overestimated number of free particles because of the stereological nature of produced samples.The present work is an alternative approach to avoid these miscalculations and establish a system of control for fluorite flotation plants. The system deals no only with the state of liberation but also the dynamic behavior of individuals particles and mineral components within the grinding-classifying and flotation circuits. It involves methods such as sieving, x-ray diffraction analysis, study of polished sections and microscopic counting of preliminarily sieved minerals particles from a fluorite processing plant, randomly dispersed on a glass slide, but not embedded in a resin mounting medium. If a complete information on the textural properties of minerals in the ore (including its mineral components distribution) can be obtained through x-ray diffraction analysis and study of polished sections, the microscopic counting is used to determinate with enough accuracy the mineral liberation, estimate the grade of fluorite ore and products, determinate the deportment and approximate recovery of individuals particles and mineral components within the investigated circuit. For a count of 100-1000 particles in each n-size range, the counting method was found to be a particularly reliable and less time consuming operation that could substitute the chemical analysis of fluorite ore for an estimate of the grade:"

Jan 1, 2003

By Rob Morrison, Andrew Scott

"Long before a modern mine commences operations it has already become a wealth of information. After start up, it can generate enormous quantities of data – especially with semi-automated data acquisition by instrumented mine equipment. Much of this data is of limited use for evaluation of (potential) performance unless it links in some way to the site business model.An underlying reason for this waste of data is that the different cultures, financial, technical, community, environmental, etc, not only have many areas of interest but also have very different conceptual models by which they evaluate performance.It is too ambitious to attempt to bring all of these cultures together – in a single step. However, the success of the Mine to Mill ™ project has demonstrated that substantial operational value can be added by using a more integrated approach to comminution. The next logical step is to integrate measured data and then to track performance from ore body model to saleable product and waste disposal.The path from resource to product also represents a path from very sparse, highly variable data to much more detailed measurement and more representative sampling. However, in both cases the data collected is usually strongly focused on the technical requirements – not on the business model.This paper emphasises the difference between data and information. There is considerable potential for confusion between the two as both data and information are often expressed as numbers. For the purpose of this paper, data and information are distinguished by their uses.A data point (or datum) is a measurement. By way of contrast, information provides a basis for decision making."

Jan 1, 2003

By John Ralston, Stephen Grano, Yongjun Peng, Daniel Fornasiero

"A specially designed mill which allowed the control of pH throughout grinding was used to study the effect of rgrinding conditions on galena flotation and galena separation from pyrite. The various reactions occurring on the mineral surface were investigated by a range of techniques, including OH- addition to maintain the grinding pH, EDTA extraction, XPS and ToF-SIMS measurements.Galena flotation and galena separation from pyrite were strongly dependent on the metal oxidation species produced on galena and pyrite surfaces under different grinding conditions. Iron oxidation species depressed both galena and pyrite flotation, whilst lead oxidation species activated pyrite but had little effect on galena. Optimum galena flotation and galena selectivity against pyrite were achieved by selecting grinding conditions that enabled lead and iron oxidation production to be controlled."

Jan 1, 2003

By Kari Moen, John Rasmus Leinum, Jarle Hjelen, Terje Malvik

"Industrial minerals may contain the same elements in approximately the same amount. In these cases backscatter electron imaging or chemical analysis are not sufficient to identify the minerals. Another problem arises when micro textures are not detectable in traditional imaging or the grain size is smaller than the X-ray spatial resolution.As a supplementary technique in these cases, application of crystallographic information by electron backscatter diffraction (EBSD) in the scanning electron microscope (SEM) may be a suitable method. The technique has been demonstrated on three Norwegian mineral raw materials and one Italian marble and shows that it has some advantages compared to traditional techniques.• quantitative measurements by ebsdCommon automatic techniques describing the mineral contents and the occurrence of minerals in free and locked particles, are based on optical-, backscattered electron (BSE)- or X-ray-signals. There are various commercial software systems on feature analysis by backscattered and X-ray signals in combination with image analysis (e.g. Oxford Inca Feature, CSIRO QemScan).Especially in silicates, the occurrence of similar elements in the different minerals is common. Sometimes the various minerals not only contain the same elements, but also approximately the same amount of each element. In these cases BSE imaging and chemical analysis are not always sufficient for identification."

Jan 1, 2003

By Malcolm Mudge

"One of the oldest mining areas in the World exist in Africa and the Middle East. This area is being exploited by foreign and local mining entities. Several large plants, both foreign and local as well as small operators, conduct their mining business on a scale which would be could be prohibited in any other part of the world. Relatively recent European disaster with tailing disposal and breakout has highlighted the problem.More important to the author is that the presence of foreign entities in zones which have not remedied the situation but has heightened the concern due to those entities using similar outrageous methods in treatment of waste. The abject misuse of technology cannot be permitted to continue and the lack of any metallurgical knowledge in the treatment of gold ores is considered deplorable for the majority of third world countries.The destruction of cyanide is simple and straightforward and requires no special skills. In South America, we developed a system that is modular, compact and can be operated in batch mode to cater for several clients, as required. Larger installations would require a separate module, as treatmentwould be on a continuous basis."

Jan 1, 2003