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By Güven Önal, Gülay Bulut, Mustafa Özer, Yunus Emre Benkli, Olgaç Kangal, Mustafa Tarkan

There are various types of natural zeolite deposits in Turkey. Naturally occurring zeolites are excluded from many important commercial applications where uniformity and purity are essential. In this paper, the beneficiation of natural zeolite, taken from western part of Turkey, was investigated. According to X-Ray Diffraction (XRD) and mineralogical studies carried out on the representative ore sample, the natural zeolite was found to be in the forms of clinoptilolite and heulandite. Clinoptilolite forms as a devitrification product of volcanic glass in tuffs. Quartz, clay minerals, orthoclase, plagioclase, biotite, seruzite-muskovite and epidote were observed as impurities. Several types of mineral processing methods were performed in order to remove impurities from the natural zeolite sample to produce high purity zeolite. Gravity separation methods such as shaking table and superpanner were carried out for separating heavy minerals, while high intensity dry magnetic separation was used for discarding magnetic minerals.

Jan 1, 2003

By Antoineta Boteva

A significant part of the currently production of the non-ferrous and precious metals is from sulfide ores. Character feature of sulfide ores is the presence in them always pyrite and wide range of different sulfide minerals else. These minerals are the carriers of valuable for industry metals. Due to the low content of the main components, very often call on the use of collective- selective flow-sheets. The extraction of minerals in the collective concentrates determined in a large extent the effectiveness of the collective-selective sheets. In conditions of bulk flotation kinetics to floatate of the various minerals is different. Due to why it is and how it can be used for a more effective selection of minerals ?this is the main task of this report. For this purpose are used results from the bulk flotation of pyrite, copper sulfides, molybdenite, galena, blenda. It is separated and place of host rocks. Base it of large experimentation material, including both electro-kinetic measurements of mineral systems, as well as laboratory flotation tests and factories monitoring it is established kinetics of flotation of mineral particles in conditions of collective flotation. Made an effort to clarify the effect as of the species and the proportion of different sulfide minerals involved in flotation pulp else. Traced was the impact of the density and aeration of the flotation pulp on deferens in kinetics of mineral flotation in condition of balk flotation. The obtained results are used to increase the efficiency of the diffraction flotation of the complex sulfide ores containing precious metals. In the schemes, it is possible precious metals to fall in the most appropriate for the next processing products. Keywords: flotation, sulphide ores, kinetic extraction

Sep 1, 2012

By V. Dementiev

Pyrite cinders is a complex raw material, in which the valuable metals are: Au(2.04 g/t), Ag(35.0 g/t), Cu(0.38%), Zn(1.1%) and Fe(56.0%). In this case high costs for mining and ore processing are not required. The hydrometallurgical treatment of pyrite cinders using thiourea, sulfite and cyanide solutions are examined in this paper. It was found that thiourea leaching is ineffective due to high consumption of thiourea and sulfuric acid. The cyanidation on pyrite cinders was conducted. Various options of the preparation of the products for the subsequent cyanidation have been examined. The tests on cyanidation process optimization were conducted. The effectiveness of these cementation methods by metallic iron or extraction for copper recovery from water phase has been shown. Zinc precipitation can be found in the form of carbonate. In order to recover noble metals from cyanide solutions, the cementation onto zinc dust was tested. The developed technology provides for recovery at 49-56%Au, 20-25%Ag, 22.5%Cu and 50%Zn during NaCN (1.4 kg/t) and CaO (6 kg/t) consumption. The results of pilot plant testing are the basis for technical regulations in order to design a pyrite cinders treatment plant. The technology has been examined in pilot-plant conditions. In this case the recovery of 54.5%Au, 45.3%Ag, 30%Cu and 49.9%Zn was achieved to provide saleable products. Keywords: pyrite cinders, thiourea leaching

Sep 1, 2012

By Mahdi Shevrini, Hamed Haghi

"In this research, the operation of screen classifying in silica processing circuits was investigated and modified by replacement of available trommel screens with teetered bed separator (TBS). In addition the effect of the mentioned replacement and addition of attrition scrubber on quality of final product, impurities removal, recovery and production rate were inspected. Considering screen efficiency problems to achieve certain particle size distribution, hydraulic classifying system was selected instead of trommel screens. Application of suggested plan improved quality and particle size distribution of produced silica significantly. Optimization of size classification in process circuit resulted in increase in production rate up to 21% (from 67% to 81%), silica recovery (from 68.35% up to 83.11%) and relative enhancement in removal of impurities such as Fe2O3 and TiO2. After optimization and stabilization of grinding and size classification section, industrial attrition scrubbing tests were carried out and the best solid percent and retention time were determined i.e. 70% and 6 minutes, respectively. Using sodium carbonate during attrition scrubbing, has major effect on removal of surface coating and staining especially sharp increase in clay removal; therefore 2 kg/t of sodium carbonate can be optimistic point of industrial procedure for this silica processing plant. It should be mentioned that application of attrition scrubbing which is followed by screw classifier for de-sliming were useful for better cumulating of particles in the range of appropriate liberation degree (+106-300µm) and efficient removal of metallic (iron and titanium oxides) and non-metallic (clays and feldspars) impurities."

Jan 1, 2014

By Xiaoping Xu, Tiansong Dong, Guosheng Wang

"Jianfengpo tin ore is located in Jiangxi Province, China. The cassiterite is fine and dispersed. It is hard to separate marmatite from a variety of sulfide minerals. Because the iron-containing sulfide minerals including pyrrhotite, pyrite and chalcopyrite are detrimental to the improvement of the grade of zinc concentrate. Besides, the presence of the iron oxides and ferro-carbonate minerals results in the difficult beneficiation of tin. Therefore, Jianfengpo tin ore is a kind of refractory cassiterite polymetallic sulfide ore. According to the properties of Jianfengpo tin ore, the technology process of "Sulphide ore preflotation-Bulk flotation of sulphur and zinc-Separation of sulphur and zinc -Magnetic separation-Gravity concentration" was developed to recover the valuable materials including marmatite, pyrite, magnetite, cassiterite and indium comprehensively. For the feed ore containing 0.87% Sn and 0.70% Zn, a zinc concentrate of 44.56% Zn with a recovery of 69.10%, a high-grade tin concentrate of 54.38% Sn with a recovery of 53.03% and a low-grade tin concentrate of 6.54% Sn with a recovery of 1.25% can be achieved in the batch flotation tests. In the industrial tests, for the feeding which contains 0.55% Sn and 0.65% Zn, the tin concentrate of 49.10% Sn with a recovery of 48.52% as well as the zinc concentrate of 45.11% Zn with a recovery of 60.10% can be produced. Thus some pyrite and magnetite concentrate are recovered as well. So Zinc, tin, sulphur and iron ores are recovered effectively by the technology."

Jan 1, 2014

By P. V. Ramesh Babu

India has sizeable number of small deposits of rare metal bearing minerals namely columbite-tantalite, pyrochlore, beryl, lepidolite, spodumene and rare-earth element bearing minerals monazite and xenotime in different parts of India. Pegmatites, alkali granites, syenites, and the derived gravel and soils are the main source for rare metal and rare earth (RMRE) minerals. The RMRE minerals are classified as prescribed substances under Atomic Energy act of 1962 keeping in view the uses in the nuclear industry. Atomic Minerals Directorate for Exploration and Research (AMD) of Department of Atomic Energy (DAE) is the sole agency responsible for exploration and exploitation of RMRE minerals in India since 1962. The latest technological advancements and applications in the field of space, electronics, communication and nuclear industry using these metals and their products have necessitated to augment the production and resources of RMRE minerals. These minerals play a significant role in the technological and economic development of the country. The light rare earth element bearing mineral monazite is abundant in beach sands and is being commercially exploited by Indian Rare Earths Limited (IREL). Columbite-tantalite, the chief source for niobium and tantalum (Nb-Ta) metals present in the pegmatitic gravel are recovered by small mobile beneficiation plants. The cut and fill method of mining adapted is eco-friendly. The processing flow-sheet consists of wet sizing at ½ in and 1mm followed by gravity concentration of sized products utilizing the methods of jigging and wet tabling. The sizing equipment include revolving and vibratory screens and the gravity concentration equipments used are fixed sieve jigs and movable screen jigs for final upgradation. The gravity concentrates are further upgraded by magnetic separation to remove magnetite and ilmenite. The mine areas are reclaimed by filling with coarse size tailings and new plantations. These mobile pilot plants were earlier operated in Bihar mica belt, Jharkhand, pegmatitic areas of Karnataka and Nellore mica belt of Andhra Pradesh and are currently being operated in Bastar-Malkangiri pegmatite belt of Chhattisgarh and pegmatites of Jharsuguda district of Orissa. Beryl, lepidolite, spodumene and cassiterite minerals are the by-products from the pegmatite ores. Fergusonite, samarskite and microlite are the other niobium and tantalum bearing minerals which are also found in pegmatites. Xenotime, the chief mineral of yttirium generally occurs in granites and pegmatites. The rare earth minerals monazite and xenotime get concentrated in the placer sands of rivers and beaches. The occurrence of xenotime in the sands of Siri River and Deo River in Chhotanagpur granitic terrain in parts of Chhattisgarh and Jharkhand are an example. These sands containing 1-2.5% heavy minerals were processed by a mobile plant consisting of sizing equipments like trommel and vibratory screen followed by separation of heavy minerals from -1mm sands with the help of gravity concentration equipments like spirals/shaking tables/sluices. Xenotime and monazite from the pre-concentrate are further separated by magnetic and electro-static methods. The present paper illustrates the pilot plant set up for the recovery of rare metal as well as rare earth minerals. Keywords: small deposits, rare earths, rare metals, pegmatite, Nb-Ta, xenotime, India

Sep 1, 2012

By I. A. Podkamennyi, O. E. Kovalchuk, G. P. Dvoychenkova

"Using the methods of electron microscopy and IR spectroscopy, mineral components in the run-of-mine kimberlites and on the surface of diamonds were identified. The mechanism and sequence of mineral formation on the surface of diamond crystals were established. Systematization and classification thereof were undertaken for the first time ever.INTRODUCTION The high content of diamonds sized -5 mm in the kimberlite ores of Western Yakutia determines their processing depth in the size class 0.5 mm and finer [1, 2]. These diamonds are recovered by grease and froth separation based on the natural hydrophobic properties of the crystals. When refractory altered kimberlite ores are fed into the industrial process, the performance of grease and froth separation of the diamond ore greatly deteriorates. [4, 10, 15, 17]. Altered kimberlites are known to contain up to 90% of secondary minerals. This reduces by up to 40% the recovery of diamonds by grease and froth separation. [6].Diamond crystals from the grease and froth separation tailings were investigated. On the surface of the examined diamonds, hydrophilic mineral formations were identified, responsible for reduced recovery by physicochemical separation methods [3, 12, 18]. The aim of this study was to identify and describe the relationship between the composition of kimberlite ores and mineral formations on the surface of diamond crystals in order to systematize, classify, and then develop methods of removal in grease and froth separation processes. MATERIALS Following materials were examined in this study: - kimberlites of various material composition, - resulting slimes, - diamond crystals from kimberlite ore processing products."

Jan 1, 2018

By Silvia França, Hudson Couto, Renata Barbosa

"The flotation process, largely used for mineral concentration processes, which is based on air bubble adhesion to the dispersed solid phase, is also being used for wastewater treatment purposes. Dissolved air flotation (DAF) is based on the separation of the solid-liquid phases with the aid of small air bubbles (10-100 µm), with high values of interfacial contact area, improving the process efficiency. In the process, the air bubbles and particles or flocs form aggregates, which rise to the surface of the flotation cell to be collected. The advantage of producing small bubbles is directly related to the fact that smaller bubbles result in greater bubble-particle interaction. Wastewater produced in alumina refinery - from the red mud filtration step - has a red colored aspect due to the presence of very fine particles of red mud and also dissolved matter that still remain in the filtrate. This wastewater might be treated, aiming to reuse the water in the refinery or discharge it properly in the environment. The aim of this study was to evaluate the DAF process efficiency for the treatment of red mud wastewater in order to decrease suspended particles and dissolved solids contents, in addition to mitigate the high causticity of this wastewater. The process efficiency was evaluated by comparing turbidity removal and total solids concentration in the treated wastewater to the feed. The influence of important variables of the DAF process as type and concentration of coagulant and flocculant were evaluated. It was possible to obtain good turbidity removal efficiencies (up to 90%) using low concentrations of coagulant (50 mg/L) and flocculant (0.5 -1.0 mg/L). In addition, for most of the experiments, the specification for effluent diposal, according to the Brazilian environmental regulation 430 (Conama, 2011): pH range 5 to 9 and turbidity < 40 NTU, was attained. These results emphasize the possibility of using the DAF as an alternative technique to settling and filtration process, that are traditionally used, for treating wastewater from the alumina industry, allowing the reuse of water in the plant or adequate discharge with less environmental impact."

Jan 1, 2014

By A. D. Shuloyakov, G. A. Finkelstein, V. I. Kurets, A. K. Vedin

"In disintegrating solid ores with mineral values disseminated in them, one of the principal tasks is to selectively separate valuable mineral particles from the matrix in which they reside, striving at the same time to keep their natural shape and size as intact as possible.The conventional mechanical disintegration methods do not meet this most important requirement in full. The other major objective here is to reduce electric power consumption during the fragmentation stage, since up to 65 per cent of the total power consumption at concentrators processing ores of non-ferrous, ferrous, rare, and precious metals is spent on disintegration steps.Numerous experiments conducted on dozens of ore types (tin, tungsten, and many others, as well as on rock containing diamonds, rubies, emeralds, etc.) have invariably demonstrated by far superior integrity of mineral values as compared with that obtained by mechanical as well as other types of disintegration.However, the process remains as power-intensive as ever which is due to the imperfect nature of the electro-technical devices that convert the network electric current into high-voltage electric impulses responsible for the disintegration process.The maximum capacity attained in disintegrating the hardest materials from 40 mm to 2 mm size in a single operating chamber with four high-voltage electrodes does not exceed 1.0-1.5 t/h. Attempts at increasing the number of electrodes and the capacity of the operating chamber have failed so far because of high overall dimensions and mass of the electrical part of the installation supplying the chamber with pulsating current, as well as of the commutation requirements. At the same time, a number of overseas operations have reported a significant breakthrough in their attempts to reduce dozens of times the overall dimensions and mass of the discharge impulse generating installation (EIS), which enables us to contemplate to increase the capacity of the EIS at least ten times in the nearest future. Yet, even with the currently achieved capacity of the EIS, these installations have found wide use in geological surveying, precious and semi-precious stones production, in grinding super hard materials, etc., since they provide spectacular selectivity of disintegration and thus the integrity of valuable mineral crystals."

Jan 1, 2003

By Vladimir Grujic, Milorad Grujic, Ivan Djurkovic, William Riggs

"In this paper, we have studied efficiency of different chemical structures of frothers on copper ore Majdanpek. The goal was to find out the best suitable chemical structure, which allows good bubble formation, size and interaction, forces on mineral surface. The particle size distribution was between 10 and 100 µm. Our research was oriented on three groups of frothers: alcohols, poly glycol ethers and poly glycols.We also used different collectors based on similar or less similar alcohol group in chemical structure as in frothers, expecting higher stability of air bubble in contact with copper minerals. Minimal potential energy was determinate in the hydrodynamic conditions for different particle sizes. It was founded that it is proportional to air bubble volume on 0.88° and contra proportional to the kinematics viscosity of pulp.Analyzing the results, we find out that poly glycols decreased surface tension the most. Also, it increased amount of coarser particles to the top of pulp. This group is less sensitive to pH value compared to the others too.From the class of frothers with higher efficiency in flotation process, we pointed OrePrep X-75 and X-133 as frothers with expressive frothing characteristic in the alkaline and low alkaline circuits. Special suitability of those frothers for floating copper minerals makes their hetero polar molecules with more than one hydrocarbon radicals connected to one polar group. However, those froters have no nether high or low solubility and are non-ionization. Those froters indicate some small collecting characteristics too. In dispersion systems, those two frothers make two types of bubbles: smaller di < 1.2 mm; V = 0.0008 cm3 and middle di < 16 mm; V = 2.2 cm3 (di – Bubble diameter, V – Bubble volume). Transportation speed of air bubbles it is possible to calculate based on equation: ?s = 27.5 * di 1.4 cm/s. Distribution of free surfaces for chalcopyrite is average 80% in the class –74µm +10µm and 20% in the class -10µm. If we get all class sizes, we find that recovery (R) depends from the time by equation:"

Jan 1, 2003

By R. Shiva Kumar, G. Sreedhar, S. Sharma

Some of the Indian origin iron ore deposits located in Bellary, Karnataka province are having peculiar characteristics of Iron ore deposits (Hematite) having Iron above 64% and 30-40% lump (-30+6mm) recovery which are not suitable to use in blast furnace due to not meeting the specification of Tumbler Index and Abrasion Index. In general for high grade Iron ores, process flow sheet involves crushing and screening (dry/wet). In the contest of high grade Iron ores located at Bellary sector of Karnataka state in India, lump generated from this process could not attain the required physical properties (Tumbler Index, Abrasion Index) and metallurgical properties , even though the grade of the lump ore is above 64% Fe. Washing techniques like Drum scrubber and Log washer play major role in improving the metallurgical properties of Iron ore lumps by removing the light and hard layers of clay, silica coated over the lumps. In this study the effects were compared of drum scrubbing and log washing on iron ore lumps. It is found that by incorporating simple washing technique i.e. drum scrubbing or log washing, Tumbler Index of Iron ore Lumps could be increased from 74% to 78% which is acceptable for use in Blast furnace. From the Drum scrubber and Log washer tests, it is clear that Log washers have an edge over Drum scrubber in removing hard coated clay on surface of Lumps. This simple washing technique facilitate us to utilize the lumps directly in blast furnace and eliminate the unnecessary crushing and grinding of the ore so as to meet the specifications of Sinter fines and pellet feed.

Jan 1, 2014

By C. L. Lin

Previous research on particle damage during high pressure grinding roll (HPGR) crushing was limited by the resolution of point-projection micro CT systems and the extent of damage was described by the percent of particles cracked for different crushing methods as determined at a voxel resolution of 40 microns. With recent advances in X-ray optics, the resolution afforded with point-projection micro CT systems has been improved by at least an order of magnitude using a lens-based X-ray micro CT system. With the use of X-ray lens imaging the resolution is determined by the lens rather than by the spot size of the micro-focus X-ray source. The high resolution X-ray micro CT (HRXMT) system made by Xradia with a voxel resolution of less than 1 micron is now being used for the characterization of particle damage during HPGR crushing. In this way, the direct 3-D determination of the internal damage of crushed ore particles which vary from 40 mm down to 100 microns in size is being studied at a voxel resolution of a few microns. The number, size, and shape of cracks can now be measured at this improved resolution and for the first time the specific crack surface area distributions of the crushed product can be calculated from HRXMT images using specially designed software tools for 3D analysis. Results from selected crushing operations are presented. Copper ore particles from HPGR crushing at high pressure (6 N/mm2) are severely damaged having crack specific surface areas as great as 10 mm2/mm3. Keywords: HPGR, particle damage, X-ray micro tomography, crack surface area

Sep 1, 2012

By Robert Dunne

A review of the current ?state of the art? of refractory gold treatment will be provided. This will include a global perspective of the refractory processes that are being practiced, where they are and some discussion on why the processes were selected. Some discussion on the challenges that face the refractory gold industry will also be provided.

Sep 1, 2012

As a leading global company in the mining sector, we are committed to sustainable development. To this end, we invest in the responsible, integrated management of economic, environmental and social issues. Vale?s objective is for our businesses to produce local, regional and global prosperity, enabling the construction of a positive legacy throughout the lifecycle of our activities. This covers everything from talking with stakeholders and preventing failures to complying with legislation, paying constant attention to environmental issues and respecting ethics in business. Keywords: sustainable development

Sep 1, 2012

By John A. Herbst

Professor A.M. Gaudin and his students at MIT were dedicated to understanding the fundamentals of mineral processing and as a consequence were constantly searching for better quantatative descriptions of size reduction, liberation and mineral separations. I have had the good fortune of meeting Professor Gaudin and working with many the modeling pioneers who followed him. I have observed first hand the refinement of mineral processing models as they increased in realisticness moving up the steps of the pyramid (see figure below) from pure empiricism to the current pinacle of physics based models. During this journey our industry benefited significanbtly as model prediction errors were reduced from ± 20% to ± 1%. Unit operation and plant simulations improved in accuracy and speed of calculations.

Sep 1, 2012

By Atul Kumar Bhatnagar

TATA STEEL is the pioneer in coal beneficiation in India. The first coal beneficiation plant was set up in 1951 at West Bokaro and subsequently in 1953 in Jharia. Over the years more beneficiation capacity was added by setting up new coal washeries in both West Bokaro and Jharia, the coal divisions of Tata Steel. currently the beneficiation capacity available is 8.5 mtp aappx Being a captive supplier supplying the coking coal as per demands of our steel works is challenging in the sense that the intent is to leverage the captive raw material advantage and select the best strategy for maximizing value up to steel making. The beneficiation plants were designed to produce clean coal up to 17% ash. With the demand of increasing productivity at the blast furnace the clean coal ash was lowered. subsequently the processes were audited and efficiency improved. The next challenge was to improve the throughputs in the existing plants to maximize the clean coal production. The upgradation was designed in house and implemented to upgrade the plant from nameplate capacity of 2.1 mtpa to 4.5 mtpa while the yearly production targets were also achieved. The presentation will detail the different phases of improvements, process followed, challenges faced, and the results as achieved in the process. Keywords: coal beneficiation, India, coal washeries, beneficiation plants XXVI INTERNATIONAL

Sep 1, 2012

By V. K. Gupta

Selection of mill size for reducing a feed material of a given size to the desired product size is generally based on the specific energy estimate obtained from Bond test. Over the last thirty years or so, an attempt has been made to develop a more accurate and powerful alternative approach based on the characterization of the particle breakage kinetics and material transport through the mill over a range of operating conditions of interest and correlating the degree of size reduction achieved with the net specific energy input to the mill. Particle breakage kinetics are described in terms of the specific grinding rate and breakage distribution parameters for the individual size fractions. Precise estimates of these parameters and the net energy input to the test ball mill (a laboratory or pilot scale mill) are important for development of desired energy-size correlations. In this context, three tasks are important: (a) preparation of the feed charge, (b) design of batch grinding experiments and (c) computational technique used for estimation of the breakage rate and breakage distribution parameters. This paper highlights several aspects of these three tasks that have been overlooked by researchers working in this field, and describes a more appropriate approach for estimation of model parameters and specific energy input. Several examples are included based on the data available in the literature and those generated in our laboratories to illustrate important points.

Sep 1, 2012

By Alain Broussaud

The lecture is about the growing role and the evolution of advanced process control (APC) in the mining and mineral processing industry, taking into account major trends in Information Technology. It reflects the standpoint of a team, which has already successfully developed APC technology for more than 20 years. Advanced process control systems tend to rely on combinations of artificial intelligence techniques or algorithms that complement each other and cooperate. Each technique or algorithm makes it possible to use certain type of knowledge about the process, so that the advanced control systems benefit at any time from the combined knowledge of process and control engineers and plant operators, from knowledge derived from past research work and process modeling, from a considerable amount of data provided by advanced instrumentation in real time, and from knowledge that can be extracted automatically and at any time from past data and images. The lecture will first review and compare the role, merits and limitations of algorithms that are used for online decision making in mineral processing plants: expert systems, fuzzy logic, neural networks, soft sensors, optimizers, and MPC controllers. The lecture will also review the role of online image analysis and sound analysis in process control. Recent developments in this area open new dimensions, in particular the ability for advanced process control algorithms to automatically explore the past, move back and forth in time in order to make better informed decisions, and the ability to cooperate with the operators for better performance. Applications will be presented. Recent progress in process simulation makes it possible to design, configure, check, and pre-tune APC systems before plant startup, opening new options for implementing APC. In conclusion, the author will share his experience about the key ingredients for sustainable success in APC Keywords: mineral processing plants, APC, MOC controllers

Sep 1, 2012

The Indian steel industry is growing at a rapid pace and expected to be the 2nd largest steel producer in the world after China. To cope up with this growth and to sustain it, the industry needs to focus on effective utilization of domestic metallurgical coals. While the importance of indigenous coal has increased, its supply from the domestic sources is declining. This is primarily due to high ash content in Indian coals leading to its difficulty in washing to a low level competitive to imported coals. Non-availability of a suitable beneficiation technology to bring down the ash to such a low level is the other reason. Effective utilization of current technologies has enabled Tata Steel to bring down the ash to 13-16% from its captive collieries. However, further lowering the ash using the conventional beneficiation technologies is difficult and unsustainable. New technologies should be developed for bringing down the ash further. A thrust area research program has been undertaken at Tata Steel for producing clean coal with 8% ash maintaining the yield currently achieved in its washeries. The technologies attempted are based on chemical beneficiation of coal. In leaching process, suitable chemicals are used for extracting ash minerals from the coal. As an alternative process, the combustible part of the coal is being extracted using a suitable organic solvent through an organo-refining process. Both the processes have been successfully developed in the laboratory and are being demonstrated in pilot scales. Various beneficiation processes practiced at Tata Steel including the efforts made for developing new processes for achieving clean coal with 8% ash have been discussed in this paper. Keywords: metallurgical coals, washing, beneficiation technologies, chemical beneficiation, leaching, solvent, and organo-refining process

Sep 1, 2012

By Hemant Nerurkar

The destination of human development journey is envisioned as human well being. Human well-being is the extent to which individual share the ability and the opportunity to live the kinds of lives they value it includes environmental security, good health and living conditions, all of which are closely related to each other. The breakthroughs, which transformed the human race, have close interdependency with the environment. With the increase in world population, the requirement of natural resources is increasing every day. The nature is still stronger than man is but we must use natural resources more responsibly. The key to our well being is sustainable development Development effort for human well being may have adverse impact on the environment also. To keep the net impact positive is critical for sustainable development. For mineral processing industry, the value of a mineral is in the actual value as perceived by the end user. The process designs, investments in technology development all have direct relationship with the value of use and making a net positive impact on our ecosystem The value proposition has shifted towards raw materials and is a big differentiator. The availability of good quality raw material is difficult or is available at a premium. The challenge today is to develop green technologies that make effective and efficient usage of low grade raw materials The low grade raw materials as available pose a significant opportunity for human race for delivering value. They offer an easier reach to a value as perceived in end use but the journey is full of challenges. The first challenge is development of technology for maximizing grade recovery as required by the downstream process. The second challenge is to make the technology viable so that it contributes value to end use and the third challenge is to keep the net impact of the process positive The mining and mineral processing fraternity, being at the beginning of this value chain is set to take the first step in this journey for a tryst with ultimate human well being. Keywords: sustainable development, challenges in mineral processing

Sep 1, 2012