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By Norman Marr

Introduction In Canada, the mining industry and water-power development are intimately associated in that mining, which ranks second among the country's primary industries, depends principally upon hydro-electric energy for its large power requirements. On the whole, the Dominion has been very favourably endowed with water-power resources; generally speaking it is a well-watered country with numerous rivers and lakes located in are as where the topography favours water-power development. Precipitation, the raw material of water power, varies from an annual fall of more than l00 inches on the Pacific coast to about 12 inches in sections of the Prairies and the Northwest Territories; in Ontario and Quebec the annual average is 24 to 40 inches and in Nova Scotia about 45 inches. In its descent to the sea, the resulting run-off, much of it from considerable altitudes, creates sources of potential energy at every rapid and fall along the country's many streams and rivers. Many of the innumerable lakes in the Dominion provide storage basins for the regulation of stream flow, thus enhancing the potential power of available sites. While water-power resources are fairly well distributed across the Dominion, as is shown on the accompanying map of Canada showing power sites (Figure 1), it is particularly fortunate that those areas which are lacking in indigenous fuels have been compensated in large degree for this scarcity by being favoured with a high proportion of the total potential water power. This has an important bearing on the mining industry in that extensive mining operations can be economically carried out in the great Canadian Shield, which is lacking in commercial coal deposits but is rich in water-power resources. This Precambrian formation, which forms a wide belt around Hudson bay and in which many metalliferous ores are found, was 'subject to severe glaciation in a recent geological period, so that its river systems are comparatively young and are characterized by numerous lakes joined by short reaches of fast water, rapids, and falls which offer frequent opportunities for power development. The western Cordilleran region, which also is important in mining, has abundant water power. The accompanying geological map (Figure 2), prepared by the Geological Survey of Canada, shows the great extent of the Precambrian and Cordilleran regions and may be compared with the map of water-power sites to show the high incidence of water-power resources in these potential mining areas in which important mineral discoveries have already been made.

Jan 1, 1949

By Jim Wickens, Andy Cole, John Pekrul

"The roaster facility at Barrick Goldstrike Mine treats double-refractory sulfidic/carbonaceous gold ore. Prior to oxidation in the roasters, the ore is ground in two parallel dry grinding circuits utilizing 19’ Ø x 75’ double rotator mills. The design plant throughput was 12,000 dstpd. However, process improvements have significantly increased throughput rates by 25-50%. The current daily throughput record is 20,078 dstpd. Grinding circuit improvements contributing to this success include feed size reduction, ball size optimization, automatic ball charging optimization, and operating strategy changes. In addition to the changes already made, this paper discusses future optimization initiatives including on-stream particle size analysis and “real-time” ore hardness determination techniques.INTRODUCTIONBarrick Goldstrike Mines is located 29 miles Northeast of Carlin, Nevada, USA. Through 2001, the property has produced over 23 million ounces of gold making it one of the premier gold operations in the world.Prior to Barrick’s ownership, the property began producing gold from a small heap leach operation in 1975. The small-scale heap leach production continued through 1986, and in January 1987, Barrick acquired the property. Increased exploration activity by Barrick significantly increased gold reserves. In August 1988, a 4,500 dstpd mill facility was commissioned to treat high grade oxide ore. Also, heap leach operations had significantly expanded. In 1990, the mill was expanded to 6,000 dstpd, and the first autoclave was commissioned to treat refractory sulfide ore. By the end of 1996, the mill and pressure oxidation facility had expanded to 16,000 dstpd and heap leaching had ceased as oxide reserves were exhausted. In 2000, a roaster facility was commissioned to treat double-refractory sulfidic/carbonaceous ore."

Jan 1, 2003

By Michel G. Grenier

Compliance with Diesel Particulate Matter (DPM) exposure regulation is currently performed using timeweighted average (TWA) sampling on underground mine workers. These samples are collected in the span of an entire shift and the resulting concentrations are compared to a legislated exposure limit. While this is very useful to determine the exposure level of an individual to DPM, it fails to clearly identify causes of exposure and highlight opportunities that could help reduce the exposure of workers in the course of the work shift. Real-time DPM monitoring measures the worker?s exposure as a function of time and helps identify circumstances where corrective actions can be taken or design changes can be made by the individual or the employer to reduce the overall exposure of the worker and peers. This work focused on obtaining DPM concentrations using a real-time polycyclic aromatic hydrocarbon (PAH) monitor. The aim was to demonstrate that this instrument, while not a direct DPM analyzer, was able to provide a concentration profile that could easily be linearly correlated to standard TWA elemental carbon measurements. In addition, several instances of improvements that could be implemented to reduce the exposure of underground employees were demonstrated.

May 1, 2010

By S. Hunt, D. de Vries

Kansanshi Copper Smelter began operation in March 2015. The smelter features a single Isasmelt furnace for smelting, one 6-in-line electric furnace for matte-settling and slag-cleaning duties, four Peirce- Smith converters and two rotary anode furnaces. A 1,450 t/day oxygen plant and a 4,085 t/day sulphuric acid plant are included in the smelter operations. This paper gives an overview of the operational performance to date with summary data for each smelter section. Challenges such as an unforeseen refractory failure in the Isasmelt furnace in 2016 are discussed. Design improvements around the electric furnace are mentioned. Plans for potential future improvements are put into context. A consistent focus on operations, maintenance and continuous improvement has seen the smelter easily achieve its nameplate capacity of 1.2 million tonnes per annum of copper concentrate throughput. The smelter now operates consistently at a concentrate throughput rate of 1.38 million tonnes per annum of copper concentrate. INTRODUCTION The smelter was commissioned in March 2015. Design and commissioning of the smelter have been discussed by de Vries, Hunt, Hanschar and Louie (2016). The smelter rapidly ramped up to achieve nameplate production (1.2 million tonnes per year concentrate) and in 2018 operated consistently at the rate of 1.38 million tonnes per year concentrate. This paper presents major operational data for each section of the plant and describes significant events and improvements during the first four years of operation. The smelter flowsheet is shown in Figure 1.

Jan 1, 2019

By Pavel Vasak

The Laurentian University Virtual Reality Laboratory (VRL) has provided a unique platform for the development and testing of novel seismic and microseismic data processing and visualization technology. In collaboration with Vale?s Creighton Mine, the technology was implemented at the mine site and consists of a VRL system and site calibrated Seismic Excavation Hazard Map (SEHM) software. The SEHM was developed as a practical solution for the mine operator to identify areas of elevated, active rock mass damage processes caused by recent mining activity. This paper is a pictorial representation of the 3D stereoscopic demonstration of the Creighton Mine seismic data distribution and interpreted SEHM for the first quarter of 2009. A live demonstration is scheduled at the Laurentian University VRL as one of the conference field trips. The demonstration highlights the technology transfer of research concepts into a near-real-time excavation hazard system that utilizes the key aspects of virtual reality technology; the ability to integrate large datasets (geology, mine excavation, (seismic) monitoring data, production scheduling, stress model, etc.); the ability to manipulate and visualize large datasets in both space and in time (mining sequence); and the ability to review the datasets by a group of experts in an immersive (3D stereoscopic), collaborative environment to better understand the processes and context of the mining-induced seismicity and evaluate potential risks to the mining operation.

Oct 1, 2010

"The Ernest Henry Mining (EHM) ore body is an iron oxide copper gold deposit with an average grade of 1.1 percent copper, 0.5 g/tonne gold and 22 percent magnetite. At the end of 2009, EHM converted the ball mill media charge from forged steel to high chrome media. At high pH values (above 10.5), forged media is passivated, so as the pH of the system drops the media corrosion rate increases and floods the system with corrosion products, affecting flotation. As the high chrome media is much more inert, pH has less of an effect on copper flotation response. Given this, the pH in the roughers was dropped from 10.6 to 9.6 and it was found that there was a slight increase in copper recovery and no statistical change in either the rougher or final copper concentrate grades for copper and gold. With the reduction in pH, there was a noticeable reduction in lime usage from 0.85 kg of lime per tonne of ore processed to 0.55 kg/t. This reduction in lime is equivalent to approximately $700,000 per annum at current production rates.INTRODUCTION The Xstrata Copper Ernest Henry Mine (EHM) is situated 38 km north east of Cloncurry, Australia. The mine began as an open-cut operation in 1998 and transitioned to a multi-sourced operation in December of 2011, utilising ore from the newly completed underground mine in addition to ore mined from the Mount Margaret Mining operations. EHM produces a combined copper gold concentrate containing 25 000 t of copper and 35 000 oz of gold annually, utilising a three stage grinding circuit along with a four stage flotation circuit. In addition to this EHM also produces 1 000 000 t of magnetite concentrate annually via a further grinding and three stage magnetic separation circuit. Based on metallurgical test work performed by Magotteaux between 2002 and 2008, the step to change from forged steel media to 18 percent chrome media was taken in 2009 in a bid to alter the pulp chemistry to improve the flotation performance in the plant (Greet, Kinal, Twomey, & Peatey, 2010). This plant trial resulted in: • Increased dissolved oxygen levels within the pulp, • A ball mill discharge Eh shift of 25 mV to more oxidising pulp potentials, and • An EDTA extractable iron percentage reduction. These improvements in the pulp chemistry resulted in an increase of 1.7 ± 0.6 percent in copper recovery and an increase of 2.9 ± 1.7 percent in gold recovery. As the plant trial using high chrome media was successful, the use of the media was adopted as the standard for the ball mill. This implementation opened the door for further process improvements around the flotation circuit."

Jan 1, 2014

By Jeffrey L. Pagnutti

Train derailment can lead to loss of capital, damage to the environment, and loss of life. Machinery condition monitoring techniques can be used to develop a structural health monitoring system for railway track to detect faults at the incipient stage, before catastrophic failure occurs. This study uses vibration measurements from a novel material haulage unit to develop a decision support system for railway track maintenance. A variety of feature sets and classifiers were compared to determine the optimal configuration for fault detection. The results highlight the shortcomings and advantages of certain methods and describe the process in which the optimal result was obtained. The Parzen data descriptor paired with a refined statistical feature set performed the task of fault detection with less than five percent false positive and false negative classification error. Overall, the outcome of these experiments indicated that condition monitoring of railway systems is a promising approach for fault detection and has the potential to avoid catastrophic failure.

May 1, 2013

By Niklas Frank

Ore and waste transports form an integral part of any mining operation and represents a substantial portion of the mine´s total operating cost. Mine layout, truck fleet and size, production rates, haulage distances, shift schedules, maintenance strategies etc. are all important and not at all static variables. They all change during the life of a mine and interact in a dynamic way. It is therefore essential for the successful mine management to constantly analyse and optimise the mine's transport systems. Önnerlöv has recently conducted a life-of-mine haulage simulation project for Zinkgruvan Mining, a medium sized, underground zinc producer, located approximately 60 kilometers south of Örebro, Sweden. The main objective of the project was to analyse and optimise the investments required to provide ore and waste haulage under changing conditions over an +10- years period: Deepening of the mine, increased production rates, changed mine layout, changed truck fleet etc. A large number of scenarios has been tested in the simulation model in order to identify the "lowest cost per ton" solution. This paper comprises an introduction of Zinkgruvan Mining and a brief background to the actual project, a description of the simulation model, project conclusions and some useful hands-on tips for mining engineers and project managers how to run a successful simulation project.

May 1, 2003

By B. Hilscher, P. Nayak, N. Yoon

"The mining industry is currently facing challenges with declining feed grades and is struggling to find solutions to improve the project’s economic value. By means of pre-concentration, ore sorting aims to separate the barren material from the valuable ore to reduce energy consumption and tailings generation, while increasing the feed grade, concentrate grade, mill recovery, and revenue. In addition, ore sorting allows the modification of deposit geometallurgy in order to allow the creation of an optimal mill feed.This paper evaluates the applicability and challenges of ore sorting by utilizing the results from four different mines, and reviews them in detail. The mines include two underground and two open pit mines that are base metal and precioius metal operations. In order to understand the applicability of ore sorting in these operations, initial rock-by-rock test results and different types of assays (atomic adsorption [AA], inductively coupled plasma [ICP], and fire assay) are utilized. Using the assay results, the grade recovery curves for ore sorting are generated and they are further improved by using and developing an ore sorting algorithm, which is discussed in this paper. The application and evaluation of ore sorting in greenfield and brownfield properties will also be discussed.The state of the art ore sorting technologies for both rock-by-rock and bulk sorting are reviewed in this paper. The future technologies on the horizon, including different combinations of sensors, are explained. The sorting technologies include, X-ray transmission (XRT), X-ray fluorescence (XRF), colour, infrared, electromagnetic, and laser induced breakdown spectroscopy (LIBS).IntroductionOre sorting is a sensor-based sorting technique introduced between the excavation stage and processing stage, where the unwanted waste is diverted to the waste dump and only the ore is sent to the mill for further processing. As a result, the quality of the material entering the mill is improved and the dilution of the ore is reduced. In greenfield projects, sensor-based ore sorting provides an opportunity to reduce the capital cost of the project and increase the return on investment (ROI). With most operations currently facing the challenge of finding a high grade deposit, having a sorting unit provides several advantages while keeping the cost at minimum."

Jan 1, 2017

By R. Knapp, R. Firlotte

"Les Terrains Auriferes (LIA) Property, formerly the Malartic Goldfield (Goldfield) mine, ceased its remaining milling operations in the fall of 1994. During the early years of mining, the mill processed a non-sulfide ore with substantial carbonate mineralization.In 1977 after an extended shutdown period, ore from a nearby property, Bousquet, was processed at the mill. That ore contained larger quantities of sulfides, and unlike the old tailings, had acid generating potential.Upon closure of the L TA mill, the closure options considered for the L TA site were to cover with:1. a thin cover of 0.5 metres of borrow material (sand and gravel) to achieve basic erosion protection/stabilization; collect acidic seepage and treat with lime.2. a 2 metres of non-acid producing tailings; final surface to be vegetated.3. an engineered oxygen barrier consisting of a multi-layer cover; final surface to be vegetated.The paper presents the technological and economical methodologies that were used to select the closure alternative, describe the associated construction challenges that were faced with the implementation of the multi-layer cover concept and presents preliminary results on the cover's performance.In addition to being the first full scale demonstration of this type of multi-layer engineered oxygen barrier cover technology, this project had the advantage of using non acid producing mine tailings as part of the reclamation solution."

Jan 1, 1997

By M. Rebolledo, N. Mora, G. Zarate

For decades, the mining industry has been focussed to find an efficient and economically attractive process for the leaching of chalcopyrite. Jetti Resources has developed a novel hydrometallurgical alternative to extract metals of value from mineral ores that the mining industry has struggled to process. Jetti’s catalytic technology, whilst being especially advantaged for extracting copper from low-grade and highly refractory minerals, such as chalcopyrite, seamlessly integrates with existing heap leaching methods and downstream processing operations. The technology uses a catalyst which weakens the metal-sulfide bond in the crystalline structure of the chalcopyrite mineral and alters the structure of the passivation layer allowing the leaching process to continue. Metallurgical test work was conducted to examine the effect of ore variability, in terms of grade and copper deportment. The results presented in this study highlight the amenability of the technology and demonstrate that it is possible to enhance leaching performance of copper primary sulfides over a wide range of copper grades, from 0.1 to 2.2%. Further, it is concluded that despite the copper grade, the tests with increasing chalcopyrite content render copper recoveries up to 4 times higher compared to the tests under non-catalyzed conditions. Jetti’s catalytic technology is currently being evaluated at larger scales, namely a commercial dump leach operation and 50-tonne crib tests. The results obtained thus far are compared to the results from conventional sulfide heap leaching tests. INTRODUCTION For decades, the mining industry has been focussed to find an efficient and economically attractive process for the leaching of chalcopyrite. Chalcopyrite (CuFeS2) is the most abundant and recalcitrant of the copper sulfides (Singer, 2017). Owing to its abundance and economic importance, it is the most demandable natural source for copper worldwide. In fact, the projected demand for copper is further expected to rise much higher beyond the current demand by the year 2020 (Panda et al., 2015). Therefore, it becomes imperative to find low intensity hydrometallurgical technologies for the extraction of copper from chalcopyrite in ores of such low-grades that are un-economic to concentrate and to augment the supply by extracting copper from ores with complex mineralogy that cannot be concentrated (Watling, 2013).

Jan 1, 2019

By V. J. Southey

HOLLINGER mining operations have required development by 24 vertical shafts having a total length of 28,160 feet. Seventeen of these are sunk from surface and seven are interior shafts. Four surface shafts and three interior shafts are now active and, excepting the recently completed new main ore-hoisting shaft, the remainder are either abandoned, or are used for passes or for ventilation. The new shaft bottoms 60 feet below the 3,050 level, but there is much work to be done before it is placed in service. The term 'shaft practice' is intended to include shaft construction and a general treatment o typical equipment. It is a large subject for an organization the size of Hollinger and this paper is intended only to present the salient features. The writer wishes to thank the management for permission to publish this information and to acknowledge the advice and criticism o A. G. Irving, chief engineer, and the willing co-operation of other members of the Hollinger staff.

Jan 1, 1939

By Louise Pearce

?Environmental and social impact assessments (ESIAs) are: ??process-driven and scientific processes ??The process entails a number of steps and procedures which result in obtaining a licenceto operate ?and moving more towards a social license to cooperate. ?However, the primary premise of ESIA is to facilitate the consideration of environment and the communities in planning and decision-making which would ultimately make it possible to arrive at decisions that are ?sustainable?. ?Hence, ensuring the development of the mining sector on a sustainable basis is a critical challenge that needs to be addressed by the global community.

May 1, 2011

By W. E. MacDonald

This paper relates the story of 100 years of mining in the Harbour Seam at the Princess Colliery, Sydney Mines, Nova Scotia. Several interesting anecdotes are included along with the discussion of the evolution of coal mining methods in the area. Finally, some of the recently introduced equipment at Princess Colliery is described, and prospects for the future of the industry are outlined.

Jan 1, 1968

By Gregg Vickell

"High tonnage, low grade gold mines such as Omai’s afford economies of scale that are unto their own insufficient to sustain profitability at today’s depressed gold price. Complimenting profitability objectives is the perpetual challenge to reduce operating costs and optimize unit operating efficiencies while being ever vigilant of issues such as environmental control.Key to achieving these objectives at Omai are throughput and availability gains, gold recovery improvements, cost cutting, a skilled workforce and reliable power generation.This paper attempts a cursory review of startup-to-date plant performance advances and future performance-driven objectives.INTRODUCTIONCommercial gold production at Omai commenced in January 1993 with annual output climbing to 250,000 opy by the end of 1994. A mill expansion completed in August 1996 increased gold production to 340,000 opy by the end of 1997. Current milling capacity is 20,000 in tpd (nom.) with actual capacity exceeding 24,000 mtpd on occasion depending on ore size and competency. Mill feed consists of hardrock (andesite, quartz diorite and rhyolite) and softrock (saprolite, laterite) at a nominal ratio of 70:30, respectively. Present day average weighted grade of the feed is 1.4 g/t gold.PROCESS DESCRIPTIONPrimary crushing, ore handling and the original 12,000 mtpd hard and soft rock SABC mill, hereafter referred to as Mill ‘A’, remains essentially as documented by Konigsmann (1 994) complete with poststartup modifications. The mill expansion, hereafter referred to as Mill ‘B’, features an 8000 mtpd hard rock SABC grinding circuit similar in configuration to Mill ‘A’ and differing only in equipment size. Mill ‘B’ includes a 9000 H.P.,reversible variable speed , single pinion drive, 32 ft. x 15 ft. SAG inill , a 7 ft. short head pebble crusher and two parallel 5400 H.P., 16.5 ft. x 30 ft. ball mills with dedicated cyclone packs consisting of D26 hydrocyclones."

Jan 1, 1999

By Virginia T. McLemore

The Gallinas Mountains are in northern Lincoln County and southern Torrance County, New Mexico, USA where a series of alkaline igneous bodies, including porphyritic latite, trachyte/syenite, andesite, and rhyolite laccoliths, flows, dikes, and plugs, have intruded Permian sedimentary rocks belonging to the Permian Abo, Yeso, and Glorieta Formations. A small amount of bastnaesite, a REE mineral, was recovered during processing for fluorite from the Gallinas Mountains. Four types of deposits are found in the Gallinas Mountains: epithermal REE-F veins, Cu-REE-F veins, REE-F breccia pipes and iron skarn deposits; all are associated with Tertiary alkaline to alkalic-calcic igneous rocks. Alteration includes brecciation, silicification, chloritization, and fenitization. District zonation is defined by Cu-REE-F (±Pb, Zn, Ag) veins that form center of the district, surrounded by REE-F veins. Carbonatites are inferred at depth by the presence of fenitization, carbonatization of the breccias, presence of REE and similarity of the intrusive rocks and mineralization to areas with known carbonatites.

May 1, 2011

By Fidelis T. Suorineni

Rapid drifting enables quicker access to orebodies, higher production rates and a resultant reduction in production cost. The Mining Innovation, Rehabilitation and Applied Research Corporation (MIRARCO) funded by the Canadian Mining Industry Research Organization (CAMIRO) has developed a methodology for safe rapid drift development within the underground metalliferrous mining industry in Canada According to industry survey, about 36% of drift development cycle time is spent on support installation. MIRARCO has developed a methodology for safe rapid drift development based on minimizing time spent on support installation. The methodology includes a critical review of the rockmass classification systems, examination of current support practices in the mining industry and civil tunneling, review of rapid drift development practice in South Africa, introduction of risk hazard procedures to account for material property variability and the development of a WIZARD as a quick decision-making tool for the implementation of the procedures. A comprehensive field data collection procedure was put in place and data collected from various mines to verify and calibrate the support selection rationale. The findings of the research programme resulted in the development of an improved rockmass classification system and showed that construction effects have drastic influence on support levels but is often not accounted for in assessing support levels. Stress effects and structurally controlled failures are the other important factors to take into account in rapid drift development. Three support classes were established for safe rapid drift development as No Systematic Support, Light Support and Strong Support. The support levels took into account cost, rate of installation and safety based on compatibility with ground characteristics. This paper describes the methodology for safe rapid drifting within the underground metalliferrous mining industry in Canada and highlights the key issues and major drivers behind their continued development at the Geomechanics Research Centre within MIRARCO.

May 1, 2004

?Why TSM in Canada ?How it was developed ?Architecture and Goverance ?COI panel ?Performance indicators and how they work ?External Verification ?Reporting ?The national organization of the Canadian mining industry ?Mining, smelting and refining of base and precious metals ?Mining of iron ore, diamonds, uranium, oil sands, coal and industrial minerals ?Many associate members ?www.mining.ca

May 1, 2011

By N. I. Basuki, E. T. C. Spooner

"The Bongara area, northern Peru, contains Zn-Pb mineralization with characteristics typical of Mississippi Valley-type (MVT) systems. The northwest-southeast-trending late Triassic-Jurassic car¬bonate host rocks of the Pucará Group were locally replaced by early (D1) and late (D2) dolomite. Fluid inclusion microthermometric data from dolomite and sphalerite are typical of MVT ore fluids (78° to 187°C; ~15-23 wt.% CaCl2 equivalent), and do not show apparent covariation between temperature and salinity.Homogenization temperature data from D1 and D2 dolomite show a decrease from northern (mean Th = 138°C) to central (mean Th = 126°C) to southern areas (mean Th = 102°C), suggesting fluid flow from north to south. Assuming a geothermal gradient of ~30°C/km and an average surface temperature of ~20°C, the lower temperature limits might approximate the ambient host-rock temperatures, whereas the upper temperature limits may represent minimum temperatures of a deeper aquifer, probably at a maximum depth of ~6000 m. The lower temperature limits are also similar to the estimated temperatures if dolomitization and mineralization took place in the Late Cretaceous at ~2000-3000 m depth, probably during the formation of the Peruvian fold and thrust belt near the present day Peru-Ecuador border.Fluid inclusion data show that the fluids in each studied location had relatively uniform temperatures and salinities during dolomitization and mineralization. A significant salinity drop and a slight temperature decrease are observed during late calcite precipitation, suggesting mixing of brines with dilute, cooler fluids."

Jan 1, 2009

By D. G. Klaren, E. F. de Boer

Self-cleaning fluidized bed heat exchangers have demonstrated unparalleled performance internationally for the implementation of indirect heat transfer in severely fouling fluid environments. The ingenious configuration of recirculated cleaning particles through the tubes of vertical shell and tube heat exchangers provides the ability to solve any problems that arise as a consequence of tube-side fouling during indirect heat transfer to process fluids or slurries. In most cases, the cleaning particles consist of chopped metal wire, however other process-specific materials have been used. In addition to the mitigation of fouling effects, a number of other significant benefits for slurry heating are afforded by the mode of operation of the self-cleaning fluidized bed heat exchangers. Increased turbulence at the slurry/tube interface is imparted by the action of the fluidised particles, resulting in very high heat transfers at relatively low liquid velocities. Furthermore, given the thixotropic nature of most process slurries, the action of the fluidised particles imparts additional shear to the process slurry, resulting in shear thinning effects with a consequent reduction in pressure drop and enhancement of heat transfer across the heat exchanger. The benefits provided by the self-cleaning fluidized bed heat exchanger make it the ideal option for the indirect heating of laterite nickel slurry for High-Pressure-Acid-Leach (HPAL) plants. This article explains the principle and application of the self-cleaning fluidized bed heat exchanger technology for the processing of laterite nickel and cobalt slurries in HPAL plants. It also presents an elegant method to revamp existing direct heated laterite nickel and cobalt processing plants into an indirect heated configuration employing self-cleaning fluidized bed heat exchangers.

Jan 1, 2004