Search Documents

By V. A. Feofanov

Technogenic water of ore mining enterprises, nonferrous metals operations, the enterprises of electroplating and instrument making, containing copper in the form of those or other connections can serve as perspective sources on receiving the copper-bearing raw material. Extraction of copper from the given water also solves a problem of water treating from a toxic component that reduces environmental load at evacuation of water in an open basin. The method of case hardening allows extracting copper selectively with reception of a deposit with the content of copper up to 70%. Weakness of the method is its efficiency basically in acid reduction, and also its low degree of copper extraction. On the basis of case hardening the method of galvanic coagulation is devised. It is based on the work of a short-circuited galvanic cell of iron-coke at variable contact of coupled metals components among themselves, cleared by the oxygen of air. The following processes of galvanic coagulation are considered: ? Extraction of copper; ? Formation ferrites of copper; ? Copper sorption on just-aggregated oxide forms of iron. Establishing conditions for passing the given stages provides an opportunity of copper extraction from technogenic water at any value of ??, content of salt and concentration of copper with reception of a compact deposit from which it is possible to extract copper by the known ways of enrichment and metallurgy. Investigations on optimization and intensification of galvanic coagulation with the purpose of reception the maximum rich deposit on copper have shown that the average contents of copper in a solution of 100~200 mg/dm3 the contents of copper in a deposit is 6%~10% at extraction 85%~90%, depending on characteristics of treated technogenic water. Using methods of scanning microscopy it is determined structures, composition and mechanism of phase formation in investigated electro-chemical process. The second stage of galvanic coagulation increases a degree of copper extraction up to 98%~99% that allows returning the cleared waters in circulation for waste recycling or evacuation in an open basin. Nowadays the method of galvanic coagulation is the most acceptable for copper extraction from technogenic water both from the point of view of efficiency and instrument setting that allows applying the method in conditions of the working enterprises.

Jan 1, 2014

By A. M. Raichur, S. P. Vijayalakshmi

Fine coal dewatering is a major problem in the coal industry because the fines hold significant amounts of water and account for two-thirds of the product surface moisture. Present methods include flocculation using polymeric flocculants followed by filtration. But the kinetics of filtration are not favorable with such flocculants. In this study, a novel method involving flocculation with microorganisms for improving the settling rates and dewatering kinetics has been investigated. Two Gram-positive microorganisms, Mycobacterium phlei and Bacillus subtilis were used as bioflocculants. The effect of time, pH and ionic strength of the electrolyte used on adhesion and flocculation were studied. Adhesion tests showed that maximum adsorption occurred in 20 minutes in the pH range of 2-7 and the total amount of bacteria adsorbed was almost the same with both the flocculants. Nearly 98% of the coal flocculated with both the microorganisms in about 5 minutes. The filtration rate of fine coal almost doubled with addition of bacteria and electrolyte and maximum filtration occurred near the point-of-zero-charge of the bacteria.

Jan 1, 2003

By A. P. Liu

Semi-industrial test on fine products of Meishan dressing plant was carried out with type RP80/25 high pressure roller mill produced by Homburg Corporation of Germany, and the influences of such factors as energy consumption, water containing, throughput and circulating load on rolling effect were investigated. Closed circuit experiment result showed that Meishan iron ore could be suitable for powder grinding with high pressure roller mill, and energy consumption of the operation was declined by 25%~30%, which was favorable for energy-saving, increasing production efficiency and improving grinding effects. According to above experimental results, this paper put forward the technical proposal of application of high pressure roller mill in Meishan, and pointed out some technical problems which needed to be settled urgently in technology disposal.

Jan 1, 2014

By J. E. Gebhardt, D. McBride, T. N. Croft, M. Cross

"Heap leaching is well-established as a relatively low-cost and low-energy method of extracting metals from low grade ores. However, the design methodology, attention to the engineering details during heap construction and the long time scale in metal recovery makes the process susceptible to significant variation in the success of a heap leach operation. Often the laboratory predicted recovery rates are not achieved on site due to poor understanding of the complex physics of flow and coupled solid-liquid-thermal reactions within the multi-dimensional heterogeneous ore body. Given the large scale of commercial operations, small changes in metal recovery can substantially change the operating profitability. While there are a variety of approaches to heap leach modeling, computational fluid dynamics (CFD) modeling coupled with leach kinetic models offers a methodology to describe and understand the complexities of heap leaching. The CFD model uses leach kinetics specific for the mineralogy of the ore, including gangue chemistry, and provides an energy balance to calculate and predict temperature. Coupled with the CFD model’s inherent capability for modeling complex fluid flow, the physics and the chemistry of the heap can be simulated. This provides a tool for engineering design, as well as forecasting heap production under different scenarios. The calibrated model is used to simulate a three-dimensional test heap under fluctuating meteorological data, such as precipitation events, periodic solution application, and notably temperature. These simulations provide support for a methodology to design and engineer heap leaching of low grade copper sulfide ore. INTRODUCTION Worldwide copper ore reserves are faced with decreasing head grades with copper sulfides, particularly chalcopyrite being the predominant mineralogy (Nesse, 2000). Heap leaching offers an economical way to recover copper from low grade ore. The ore is stacked and a leach solution is applied and allowed to trickle though the porous bed of ore to extract target metals. The heap can be built with run of mine material or crushed ore and is constructed in order to achieve percolation of the leach solution to all regions. Bartlett (1998) provides an authoritative overview of the solution mining process where the leach solution interacts with the solid, the lixiviant dissolves the target minerals from the solid into the solution, and the dissolved species are transported out of the heap for subsequent recovery. Petersen (2016) provides a recent review of heap leach technology and emerging and potential future applications, and Ghorbani et al. (2016) summarizes the current state and challenges of the technology. Early applications of heap leaching offered a low cost technique to achieve high recoveries from oxide ores, typically greater than 70% depending upon the kinetics of reaction. As world copper resources transition to mainly copper sulfide mineralogy, such as chalcopyrite based ores, achieving high recovery from these copper sulfide deposits is proving more difficult due to the complexity of the leach kinetics, which leads to low leaching efficiency."

Jan 1, 2018

By P. Coghill, P. Revell

"Geo-sensing is the ability to routinely measure or infer rock properties at a range of scales using non-destructive scanning devices. These devices can provide information and data flows to support integrated decision making across the minerals value chain. Geo-sensing has been used for many years in minerals exploration using technologies such as satellite imaging and airborne geophysics but to date the use of sensing technologies in between the mine and mill has been very limited. The aim of this research is to develop new mineral sensing technologies that can enable grade engineered ore streams through the rejection of low value gangue or deleterious elements either in the pit or during transfer to the mill. This paper focusses on the research and development being carried out by the Cooperative Research Centre for Optimising Resource Extraction (CRC ORE) and its associated members on new sensing technologies. At the start of their development these technologies were classified on the Technology Readiness Level scale at 3 (TRL3), equivalent to a proof of concept. Laboratory testing and design is aimed at progressing these sensing technologies to TRL5 which is ready for testing at an end users site. New data obtained during the laboratory testing and design phases are presented in the paper demonstrating performance specifications such as detection limits and measurement speed which can be used to infer the pod size of gangue that can be rejected at scale. Grade Engineering® and coarse gangue rejection are considered as key drivers for the mining industry to address the higher mining, processing and environmental costs associated with ore bodies with declining grades. This is an industry wide problem and the development of mineral sensors is seen as key enabling technologies for Grade Engineering® and coarse gangue rejection. The technologies presented in this paper enhance value through early decision making of ore quality and improve the overall resource value case through improved grade and throughput engineering."

Jan 1, 2018

By R. C. Miranda

Artificial vision systems are increasingly used to assist humans to perform different tasks in different areas. These systems are able to recognize patterns in complex images, which can provide multiple data. Currently, vision systems are used in both; monitoring traffic - which uses radars for vehicular plate recognition- as in metallurgical and food industries for strict quality inspections. Their use in mining occurs in measuring the speed of froth over the lip of a cell, in determining the shape and size of pellets, in obtaining from the tendency of mineral content and as a replacement for laboratory analysis of particle size. With this advanced tool, it is possible to achieve significant improvements in quality, productivity, and especially in reducing costs in pelletizing plant of iron ore. The objective of this paper is to contemplate the current situation of image analysis in the pelleting plants and glimpse at the potential applications that are being developed. This paper also presents the conception and implementation of an automatic control system of the pellets size distribution applied on a pelletizing plant of iron ore. The article demonstrates the strategy used for measuring the size distribution of the iron ore pellets, based on image analysis and the strategy implemented on advanced process control, which shows substantial gain on plant performance.

Sep 1, 2012

By E. A. Bekchurina, Yu. P. Morozov

"This paper presents the results of a study of the concentration of flotation froths in tapered chutes. The tests were conducted on lab and full-scale plants, and the results obtained were mathematically processed. The kinetics of monophase recovery from a stationary flotation froth, hydrodynamics of froth flows traveling in a tapered chute were investigated. The effect was studied of the mass fraction of the valuable component in the chute feed, yield of the chute’s overflow, and chute design on the concentration performance. Processing of the collected data revealed the general laws of the process and allowed to develop a technique for modeling concentration of the flotation froths of sulphide copper ore in a tapered chute to predict the performance without testing. It was found that concentration in tapered chutes allows to obtain products that are comparable in quality with froths after one or several cleaner flotation stages.INTRODUCTIONThe present production expansion rates require continuous improvement in the grade of flotation concentrates, while the grade of the mineral feed is constantly deteriorating. This leads to a significant complication of flotation flowcharts. Flowcharts become multi-staged with multiple cleaner flotations, negatively affecting the production costs.In recent years, researchers are paying close attention to the processes occurring in the froth layer in the flotation cells. Improving the concentrate grade is facilitated by secondary concentration of minerals in the froth layer, which consists in fixing the hydrophobic particles released as a result of the coalescence of the bubbles of the upper layer when moving downward at the liquid-gas interface of the froth layer. In this case, the released hydrophilic particles, trapped in the froth layer as a result of mechanical removal, migrate from the froth together with the liquid phase."

Jan 1, 2018

By A. V. Zimin

It is a well-known fact that usage of reverse cationic flotation in magnetite ores processing enables to improve the quality of magnetite concentrates. We designed an iron ore concentrate technology (with 70 -71 % of iron) including reverse cationic flotation in pneumo-mechanical flotators RIF (developed by RIVS Corporation, Russia) with good biodegradable etheramines as collectors for flotation of quartz. Practical application of high biodegradable flotation reagents decreases environmental impact risk of objects and enterprises of mining industrial complex. This work presents results of development of flotation technology for production of high quality ferruginous concentrates from magnetite ores of Russia and Ukraine deposits. Keywords: magnetite ores, reverse cationic flotation, ferruginous concentrates, pneumatic-mechanical flotation machines, environmental impact

Sep 1, 2012

By Leopoldo Gutierrez

Eight oil sand ores with the bitumen content ranging between 3.6 and 15 wt.% and the fines content (-44 micrometers size fraction) between 9 and 69 vol.% were subjected to the standard alkali extraction test used to measure the degree of oxidation of metallurgical coals. The results showed that there is a strong correlation between the absorbance of extracted solutions at a wavelength of 520 nm and the ratio of the fines content to the bitumen content. The latter factor is directly relevant to assessing the extractability of bitumen from oil sand ores. Bitumen extraction tests showed that the bitumen recovery decreased from 90 % to 30 % when the absorbance at 520 nm increased from 0.23 to 0.64. A comparison of the UV/visible spectra of solutions obtained from the alkali extraction tests with solutions of Aldrich Humic Acids suggest that low bitumen/high fines oil sand ores release substantial amounts of organic matter very similar, if not identical, to humic acids. In contrast, high-bitumen and low-fines ores do not release as much of the organic matter, and UV spectra of these leached substances are quite different from those of humic acids. Overall, the results show that chemical composition of bitumen in the tested ores varies greatly with ore type and oxidation, and that the alkali extraction test is a promising technique to quickly assess the extractability of bitumen from a given ore type.

Sep 1, 2012

By Shuji Owada, Mayumi Ito, Takehiko Nishimura, Toru Yamashita, Sadayuki Shinozaki, Takashi Ando, Tomoe Ota

Electrical disintegration (ED) was applied to Nantun coal (China) in order to improve liberation of coal substance for the pretreatment of producing “Hyper Coal” of which the combustion gas was planning to inject directly to turbine for power generation. It has been found that many cracks generated in the ED were existent at phase boundaries with mineral matters and liberation of coal substance became much higher than that in mechanical comminution methods such as roll crusher. Since the ED occurred more easily (with lower voltage applied) for the coals of higher mineral content, it is considered that this method could make a better contribution especially to comminute middling coals. We also found that the ED technique could apply not only single particles but also to coal particles assemblage, keeping almost the same or higher disintegration efficiency. In the mineral matters, Si and Al components were preferentially well liberated by the ED.

Jan 1, 2003

By Komar Kawatra, Joseph Halt

"Bentonite clay has been the traditional binder for iron ore pellets. However, bentonite increases pellets’ silica contents and is expensive. Researchers have proposed lowering bentonite doses by mixing it with other common binders. These mixtures may only be successful if the fundamental bonding mechanisms are understood. For example, what happens when bentonite (physical bonding) is mixed with fly-ash (chemical bonding)? What happens when bentonite is mixed with cornstarch (physical bonding)? In this paper, experiments are described where bentonite was mixed with various ratios of cornstarch and fly-ash, and pellets were agglomerated using 0.66 % w/w binder. Ca(OH)2 and CaCl2 were added as activator and accelerator, respectively, to the bentonite-fly ash mixture. Curves of pellet dry strength vs. bentonite-starch ratio were linear, suggesting the physical-physical bonding mechanisms were compatible - acceptable strengths (> 22 N) were produced at all bentonite-to-starch ratios. This was contrary to bentonite-fly ash mixtures, which displayed dry strength curves with a noticeable minimum due to competing binding mechanisms. Bentonite alone and fly ash alone produced acceptable strengths (> 22 N), but their mixtures resulted in weak pellets. Due to the positive results using cornstarch (CS) binders, the effects of CS solubility in water were investigated using two CS with high and low solubility (60 and 7.5 %). CS was premixed with bentonite at various ratios (0, 20, 40, 60, 80, 100 %). Pellets were agglomerated using 0.66 % w/w binder. The dry strength of pellets ranged from 50-300 N using the high solubility CS mixtures, and from 50-85 N using the low solubility CS mixtures. Fired strengths exceeded 2200 N/pellet at all bentonite-cornstarch ratios. This research showed that cornstarch solubility is an important factor in determining its effectiveness as a binder for iron ore concentrates, but significant work is still necessary before it can be used as a bentonite replacement."

Jan 1, 2014

By S. Banisi, E. Arghavani, Gh. Parsapour, S. Mousavi

Maximization of water recovery in thickeners is an essential step in the mineral processing industries. The Gol-E-Gohar iorn ore processing plant uses a center pier thickener with a diameter of 38 m and depth of 4 m. The feed rate is 50 t/h solids with a concentration of 5% (w/w), and it has been designed to provide an underflow containing 50% solids. The performance of the thickener was not as expected judged by the overflow stream containing 0.6% solids and water loss of 52 m3/h in the underflow. A criterion called the index of flocculation incorporating the perimeter-based fractal dimension of flocs, floc size, and settling velocities was proposed and used to determine the optimum flocculant dosage which was found to be 20 g/t. The fractal dimension of flocs in a pulp containing 5% solids was found to be between 1.16 (no flocculant) and 1.56 (40 g/t flocculant) which indicated highly branched and loosely bound structures for the flocs as flocculant dosage increased. At these conditions, the size of the flocs which was recorded by a digital microscope increased from 93 µm to 403 µm. A new feedwell with a special design with the aim of preventing flocs breakage and maximizing energy dissipation of pulp was constructed and installed. These modifications led to an increase in the thickener drivehead torque from 5% to 18% of the rated torque, indicating a higher bed depth. Finally, installation of a PID controller reduced the drivehead torque relative oscillation from 52.0% to 12.7%. These changes increased the solids concentration of the underflow from 49.0% to 56.9%, decreased the overflow solids concentration from 0.6 % to values smaller than 0.01% and resulted in a reduction of 27% in water loss in the thickener underflow.

Jan 1, 2014

By R. Batterham

"The history of mineral processing is indeed long and has always been tied to mining methods of the day. While many new processes and devices have been developed, the most significant trend in recent times has been the ever increasing scale of operations. There is serious doubt this ongoing trend is enough to match the global trend of falling grades and rising energy demands needed for mineral processing. As well we see that globally, the social licence to operate for mining (and hence mineral processing) is far from secure. Indeed, some argue that mining as we know it is dying and in the future, mining will be much more environmentally secure, even to the extent of insisting upon “in place” recovery and only bringing to the surface the valued product. In this paper we comment on the ramifications of broader uptake of more sustainable mining for mineral processing methods and address the specific question of whether recent progress in in place recovery will lead to a timely breakthrough. The answer proposed is that this is possible in the next 10 - 20 years but in the meantime, the focus is just as likely to be on removal of waste much earlier in circuits. Either way, mineral processing as we know it will change significantly. INTRODUCTION Mineral processing has a long history well covered in a recent publication (Habashi, 2006) who points out “the ancient Egyptians knew already that it would be easier to melt an earth rich in gold particles than another which is poor. As a result, all efforts were made to enrich the gold by washing away the light gangue minerals. Similarly, another ancient method for enriching gold particles from a river stream was by means of fleece, hence the Greek myth of the “golden fleece”. Since the middle ages, striving for improved economics has driven a string of innovative developments in milling and separation. The reader is again referred to the informative and illustrative text by Habashi."

Jan 1, 2018

By Vladko Panayotov, Marinela Panayotova

"Recently, in order to extract metals, the industry is trying to process old metallurgical slag. The material requires very fine grinding that results in enhanced slime-formation. This in turn leads to problems in the course of the flotation process and to a loss of metal. In addition, it causes difficulties in the wastewater treatment aimed at water reuse. The aggregation and separation of the fine particles and their further subjecting to mineral processing would result in more efficient use of raw materials. Closing the water cycle also would be facilitated. The paper presents results from studying sixteen flocculation reagents, commercially available for treating municipal wastewater, including products based on nanotechnology, for their ability to rend the production wastewater in suitable for reuse in the flotation. It turned out that, from all studied reagents, the cationic C-587 is suitable for the purpose. Some of reagents were studied for their ability to flocculate selectively, in presence of coke fines, rich in copper fines which are produced at grinding of a slag from lead-zinc metallurgy. Most promising reagents are chosen, based on the chemical analysis of the flocculated materials. Open-cycle rough copper flotation experiments with the flocculated fines and recycled wastewater gave encouraging results."

Jan 1, 2014

By D. B. Mazzinghy, L. C. de R. Machado, H. Delboni, M. G. Bergerman

"The use of vertical stirred mills in the mining industry has increased remarkably over the past few decades, as a result of growing requirement for finer ore grinding. This equipment delivers higher energy efficiency in fine grinding operations when compared to conventional tubular mills. Methods for designing vertical stirred mills involve operational experience, pilot plants and bench tests. An important issue is that these tests require, at a laboratory scale, at least 10–20 kg of material, depending on its density, which is not available in many cases, particularly in the early stages of greenfield projects. For the regrind of flotation concentrates, several bench scale flotation cycles are required to generate such a sample. This paper describes the development of a laboratory jar mill test using a 6”x8” jar – smaller than that commonly used – based on the overall specific energy method, which requires significantly less mass compared with existing tests. The proposed test has proven to be more practical than tests normally used, requiring about a quarter of the mass, and also shows good adherence to industrial results for the studied iron ore processing plant. INTRODUCTION A significant demand for finer grinding has been noticed over the past few decades in several mining projects to achieve the mineral liberation required for the concentration of valuable minerals. However, the finer the product size, the greater the grinding energy consumption, resulting in an overall increase in operating costs, which may reach or even exceed 50% of the mineral processing cost (VIEIRA, PERES, 2013; DANIEL, LEWIS-GREY, 2011). Comminution technology can have a major impact on subsequent ore concentration stages (DANIEL, LEWIS-GREY, 2011; MARSDEN, 2009; NAPIER-MUNN, 2012; PEASE et al., 2010), which further strengthens the importance of proper technology and equipment selection. Adequate grinding circuit selection and design is thus a key aspect associated with mining projects."

Jan 1, 2018

By Marzio Piller, Girolamo Belardi, Jure Mencinger, Paolo Bozano, Gianni Schena

"The hydrodynamics of the Tri-Flo™, a two stage cylindrical cyclone used in dense media separation, is studied using Computational Fluid Dynamics. The flow field is simulated with an Euler-Euler Volume of Fluid two-phase approach and the Reynolds stress turbulence model.A unique feature of the device is that the separation medium suspension is pumped and introduced tangentially into the two cylindrical compartments while the raw feed is conveyed to the feed hopper and fed at the axial inlet. This feature allows to use less pumping energy and limits the unavoidable production of fines. The Tri-Flo™ complex flow pattern is little known but central to the efficiency of the separation.The velocity field is computed within the two compartments of the separator. The interface of the air-core that forms in the inner axial part of the cylindrical sections is identified and visualized. The numerical results for a reduced-size 100 mm ID Tri-Flo™ are compared against laser Doppler measurements on a transparent acrylic model (Chinè, 1995) operated with water. The robustness of the model and its prediction capability are verified.The possibility to accurately predict the velocity profiles within the vessel and their dependence on the main Tri-Flo™ operating and geometrical variables paves the way to a better understanding of the functioning of the separator, its design improvements and scale-up."

Jan 1, 2014

By M. Wierink

The lifecycle of a resource, specifically a metal, is often depicted as circle from primary production from mining to minerals processing and via manufacturing and use to disposal and recycling. When a material is recycled, it is considered as saved energy compared to producing the material from primary source. This is, however, a simplified representation. At each step of the life cycle, there are changes in the quality of the material due to different materials chemical and physical interaction, phase transformations due to diffusion, radiation etc. Due to these physical and chemical phenomena there are losses of material, which as determined by thermodynamics are not recoverable within the life cycle. This can be considered as an increase embodied energy per mass unit of substance and loss exergy from the material cycle. With low cyclic loss, the material will remain in the recycling loop for a long time, while with high cyclic loss it will disappear fast. Where you put the material determines how fast it disappears from the resource cycle. In this research paper the phenomena of quality degradation of material and idea of increase of embodied energy and exergy loss within a resource cycles is portrayed. The cyclic nature of material states and transitions and energy consequences of material quality degradation as well as the parameters affecting the length of the time scales of the material cycles are described. Currently the cyclic embedded energy and the history of material is not taken under consideration in generic life cycle assessment. This easily results into a conclusion that lifetime of product is optimized only in terms of how much energy an appliance uses during its lifetime, while ignoring the loss of embedded energy due to the effects caused by the environs the material is subjected to during the cycle. Better description of the time properties of material give us a possibility to design toward optimum lifetime of products in terms of resource efficiency. Keywords: product lifetime, material lifetime, recycling, cyclic resource efficiency, material state, material quality, exergy, embodied energy

Sep 1, 2012

By Reza M. Rahman

The froth phase plays an important role in the flotation and upgrading of the final concentrate. At present, the techniques that have been used in the mineral industry to measure the froth recovery have limitations. The aim of this paper is to investigate the performance of the froth in an industrial flotation cell. A unique device has been developed which is capable of decoupling the froth zone from the pulp zone. It consists of two concentric tubes. The inner tube acts as a dropback collection chamber or catcher. The particles that detach from the froth phase fall directly into the catcher and are collected as froth dropback. The froth recovery measurements were carried out in a rougher bank of a copper concentrator treating sulphide minerals. The dropback device is designed so that it can be immersed into a plant size flotation cell and plant froth recovery measurements can be taken at any given time. During the experiments, the bubbles laden with valuable mineral particles entered the device from the plant flotation cell, subsequently rising to form a froth layer at the top of the device. The particles that detached from the froth zone were collected in the dropback collection chamber whereas the concentrate sample was collected by a launder. By drying, sizing and chemical analysis of the concentrate and dropback samples, the froth recovery, was estimated on the basis of the valuable component. The effect of air rate on froth recovery was also investigated. Keywords: flotation, froth, dropback, froth recovery

Sep 1, 2012

By J. Kolacz

A new optical sorting system based on a complex image analysis and high definition imaging has been developed by Comex. The image analysis is based on high definition cameras of different types and advanced filtration tools for verification of waste particles. Different mineral properties are used to identify the processed material. The system is further combined with a high speed rejection mechanism based on FPGA technology and operating in real time conditions. This provides a minimal error when removing waste particles from the sorted material.

Jan 1, 2014

By A. Zangooi

Frothers play major roles in flotation through interaction at the air/water interface. A method of determining frother adsorption density (coverage), i.e., the number of molecules per unit of interfacial area of bubble surface, is introduced. The technique is based on mass balancing the frother around a continuously operated bubble column. The mass balance requires collection of bubbles before they burst. The column design and operating procedure is reviewed, and some preliminary results discussed. Keywords: flotation, colorimetric frother analysis technique, frother mass balance, coverage

Sep 1, 2012