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By D. W. Boydell

The response of reclaimed gold tailings to acid leaching was investigated in the laboratory, followed by a pilot-plant program in which the operations of CCD, CIX and SX were tested with plant feed material. These results formed the basis for the design of the extension to the existing uranium plant at Blyvooruitzicht Gold Mine, commissioned in July 1977. This circuit consists of slimes-dam reclamation by bucket-wheel excavator at a rate of 100,000 t solids per month, acid leaching in pachucas, a five-stage CCD washing section, two parallel C1X absorption columns and two elution columns, SX and an ADU precipitation section. Barren solution is recycled to the CCD section as wash and to the repulper at the slimes dam. The performance of the plant during the first year of operation is compared with the predictions on which the plant design was based. Rated capacity was achieved within three weeks of start-up at a nominal dissolved uranium recovery in the ion-exchange section of around 98%. Owing to recycle, the over-all recovery in the ion-exchange and solvent extraction sections is somewhat higher than this figure.

Jan 1, 1979

By M. Phylli Bray

"Mining has the reputation of being a very ""macho"" industry. Recently, wider educational opportunities for women in nontraditional occupations and changes in mine technology have combined to make mining a viable career choice for women also. To benefit from this new resource, the mining industry faces the challenge of developing a different work environment from the one now burdened with sexism. Management supported initiatives are needed to facilitate such a transformation. The same rethinking of gender attitudes might also be extended to mining women in their traditional role as ""wife of"". The assumption that the male worker's wife is an unpaid adjunct is being questioned. It is suggested that women's separate concerns both as helpmate and as part of the mining workforce should be considered when planning for mining into the 21st century.IntroductionI must confess that, during the preparation of this paper, there have been many moments when I questioned my temerity. After all, I am not male, I am not an engineer, and I have never had a position in mine management. But as the wife of a mining engineer and a long-time resident of Northern Ontario mining towns, I do have an interest in the mining industry. This interest has had little to do with the technical and management aspects of the industry. Instead my research has been concerned with the impact the mining industry has on the people involved, particularly women, whether directly as employees or indirectly as wives. As I look toward the 21st century, I believe that the whole question of gender relations in the mining industry is one of the critical management issues smouldering below the surface."

Jan 1, 1995

By Dillon. Patricia

Business Growth ?Coal ?Targeting 30 million tonnes by 2013 compared to 19 million tonnes produced in 2009 ?Expanding Energy Business unit (Oil Sands) ?Copper -Strong growth potential for existing operations and development projects ?New gold strategy recently launched ?New markets for zinc Need to retain existing and attract new employees to support growth Engaged Employee ?Has a positive attitude towards the organization and its values ?Is a person who is fully involved in, and enthusiastic about, his or her work Engaged employees are more likely to stay with the organization.

May 1, 2010

This paper describes the results of a laboratory study on the upgrading of Algoma siderite by the amine flotation of silica and silicate gangue. The experiments indicate that a virtually complete removal of silica is possible in a rougher flotation con-ducted in tap water at natural pH, without prior desliming of the ore. Grinding considerably finer than the apparent liberation size is essential for maximum silica rejection. A cationic collector, Aeromine 3037, gave best results when used in combination with a modifier. Of the several modifiers tested, a Dutch potato dextrin, Dextrin 4356, was found to be the most effective. Both iron recovery and the grade of the final iron product are enhanced by floating the pyrite contained in the ore prior to the amine flotation of the silica, and by scalping the magnetics from the silica concentrate. F OR over twenty years, the Algoma Ore Properties Division of The Algoma Steel

Jan 1, 1963

By H. C. L. Reemeyer

"The mining industry faces increasing economic, environmental and social challenges, as easier deposits deplete and ores become more difficult to mine and process; head grades decline; projects migrate to increasingly remote and difficult geographies; and the industry faces more stringent environmental and social standards. While these factors increase costs and risks, they also present opportunities for a more integrated approach to mining, processing, materials handling and waste management. Two key areas of risk are in tailings and water management. As mining and processing tonnage rates continue to increase, the disturbance footprints, water and energy consumption and scale of tailings storage facilities also rise. These factors can be mitigated by more selective mining, ore sorting and pre-concentration, and more intensive tailings dewatering. Such alternatives must be considered in conjunction with the selection of mining method, metallurgical flowsheets, major equipment selection, and key process design criteria. For example, increasing the grind size of a concentrator reduces energy consumption and eases tailings dewatering, but may cause challenges with metal recovery. Emerging technologies will be reviewed, and economic and environmental trade-offs for eco-efficient alternatives will be presented for metal sulfide mines.INTRODUCTION The metals mining industry faces significant challenges that can affect its financial viability and social license to operate. There has been a consistent decline in ore grades and a relentless push towards larger operations to capture perceived economies of scale. With these larger operations, the environmental footprint of mines has increased. Water and energy consumption, and resulting GHG emissions have also risen. In recent years, two issues have raised special concerns for stakeholders and companies: • Water scarcity, particularly in drier regions of the world such as Northern Chile, SW USA, Southern Africa and Australia • Tailings risks, following the high-profile failures of the Fundao tailings dam in Minas Gerais, Brazil in 2015 and the Mount Polley tailings dam in BC, Canada in 2014"

Jan 1, 2017

By Yongqiang Liu

Background For refractory gold ores with high carbonate contents ! Acid pressure oxidation ! High acid consumption (if low sulfur content) ! Low oxidation efficiency due to CO2 in autoclave ! Problems with slimy precipitates (gypsum, etc.) ! Alkaline pressure oxidation ! Difficulty in fixing arsenic ! Low gold dissolution due to iron hydroxides/oxides coating ! High reagent costs Summary ! Carbonate and sulfide minerals had similar floatability across the pH range tested (5 - 12) using sodium oleate as a collector; ! Thioglycollic acid or citric acid depressed the flotation of pyrite but could not depress chalcopyrite when used alone; ! Combination of thioglycollic acid and citric acid had a much stronger depressive effect, and the mixture depressed chalcopyrite as well as pyrite between pH 8 and 11 without affecting the flotation of calcite and dolomite; ! Calcite could be separated from chalcopyrite and pyrite; dolomite could be separated from pyrite but not from chalcopyrite under the tested conditions.

Apr 1, 2005

By A. Rodriguez-Prado, R. L. Legge, W. C. Lennox

ABSTRACT It is possible to adequately describe chemical reduction of hexavalent chromium, Cr(VI), in industrial and mining wastewater in constructed wetlands by applying different kinetic models (e.g., halforder, second-order). Accounting for hydraulic transport of contaminants in reduction equations can also improve such description. The authors developed an explicit advection-dispersion bulk flow equation and applied it to model Cr(VI) reduction in laboratory wetland mesocosms. The results indicated that the model adequately described wetland exit Cr(VI) concentrations and Cr(VI) reduction, representing an improvement over the commonly used graphic method and potentially improving the wetland design.

Jan 1, 2014

By André van Wageningen

Since the beginning of this century Boliden Mineral and Atlas Copco have worked together in stages on improving the accuracy and quality of drilling. Navigation of the drill rigs with IREDES has been in use in the Boliden mines for several years. Recently the capability of the system has extended with map navigation to more accurately follow the ore in cut&fill mines. The system allows for changes on the individual round level to follow the ore without changing the whole design for the heading. Those changes are done in a CAD-system and remove the need for face markings and will allow for even better accuracy in both height and wall position. All the information between the CAD-system and the drill rigs is exchanged using the IREDES standard. This paper describes the workflow and the use of the IREDES standard.

Oct 1, 2009

By J. P. Sims

Abstract - Ultramafic to mafic igneous intrusions of the Las Aguilas district form part of a belt of generally mafic plutonic bodies within medium- and high-grade early Paleozoic metamorphic rocks in the southern Sierras Pampeanas region, Province of San Luis. The intrusions host the largest known nickel sulfide resource in Argentina and contain significant Cu, Co and PGE mineralization (2.2 Mt at 0.5% Ni, 0.5% Cu, 0.035% Co). Sulfides at Las Aguilas Este, one of two principal mineralized zones, are hosted by a body comprising subvertically dipping units of predominantly orthopyroxenite and melanorite cumulate, with lesser dunite, harzburgite, norite, leuconorite, and amphibolite. The units are zoned horizontally from ultramafic to mafic compositions, representing primary magmatic zonation away from an original base or side of the intrusion. Intercumulus nettextured and disseminated aggregates of pyrrhotite-chalcopyrite-pentlandite are concentrated in the peridotitic zones and extend into melanorite. Whole rock major and trace element compositions, and olivine chemistry, indicate that the parent magma was gabbroic/basaltic with 100 (Mg/Mg+Fe) near 59, and resembles tholeiitic magmas generated in subduction-related arc, or back-arc settings. Unusually aluminous Cr-bearing spinel is compositionally similar to those in some synorogenic mafic/ultramafic plutons in magmatic arc settings. Relatively Ni-depleted olivines and low Cu/Pd ratios are indicative of magmatic sulfide segregation early in the crystallization of the magma. Early orthopyroxene saturation and virtual lack of clinopyroxene, in conjunction with sulfur isotope values up to +6.6 ‰, spinel compositions, and presence of graphite, phlogopite and magmatic hornblende, all attest to probable crustal contamination of the parent magma. Assimilation of crustal sulfur may have been crucial in the early attainment of sulfide saturation and resultant formation of magmatic Ni-Cu sulfide mineralization. Fabrics, textures and mineralogy of the intrusions and country rocks and U-Pb zircon dating indicate syntectonic-synmetamorphic emplacement at 478±6 Ma during the Famatinian (Ordovician) orogeny. Minor to locally significant recrystallization and deformation of mafic-ultramafic rocks and redistribution of sulfides and PGE occurred during and following the Famatinian orogeny. The Las Aguilas intrusion is one of several tholeiitic mafic-ultramafic intrusive complexes within an Ordovician arc - back-arc system in the Sierras Pampeanas. Aeromagnetic datasets and regional mapping suggest there is further potential for intrusion-hosted Ni-Cu mineralization along this eroded magmatic arc.

Jan 1, 1999

By S. C. Tadolini

"Roof bolts are the primary means of roof support in underground mines in the United States. Presently, post installation loads are measured on about 10% of the expansion anchor and combination bolts by using standard torque wrenches that Unit the accuracy of the measurements to about ±30%. No system has been available for measuring the loads generated on full-column resin grouted bolts. Mine roof bolts are long, slender, non-uniformly sized, roughly forged, and placed in a corrosive environment, creating obstacles for researchers trying to utilize ultrasonic reflection techniques to measure strain. A complete measurement system has now been developed by the U.S. Bureau of Mines, Denver Research Center. This system is being used successfully in determining loads measured on expansion anchor and combination bolting systems, examining the transfer mechanics of full-column, resin-grouted bolts, and measuring loads generated on bolts in an underground roadway support system.IntroductionMillions of roof bolts are used each year to provide structural support in underground U.S. metal, non-metal, and coal mines. Approximately 45% of the bolts used are expansion anchor, 45% are resin-assisted combination or full-column resin-grouted, and 10% are friction anchored. The effectiveness of these bolting types is dependent on a number of factors including rock density, bolt length, in situ stresses, rock properties, bolt pattern, installation tension, etc. When implementing expansion anchor and resin assisted combination bolts , installation and post-installation tension, or load, is a major determinant of support quality and subsequent behaviour of the reinforced roof. The method by which these systems carry roof loads is well understood and documented(1,2).The importance of these installation and long-term bolt tension measurements is well recognized and are required in the federal government regulations(3). A statistical sample of the bolts, lout of 4 during installation and lout of 10 inby the last open crosscut, is required to be measured using current torque wrench technology. The disadvantages of this system are the disturbance and weakening of the anchorage and limitations of accuracy to approximately ± 30%. The method by which resin-grouted bolting systems carry roof loads is much less understood, mainly because testing procedures used to evaluate point-anchor systems are not effective on resin-grouted bolts.Due to these problems, the U.S. Bureau of Mines designed a measurement technique that provided a highly accurate, low cost-per- bolt system that led to the development of ultrasonic pulse echo instrumentation. The original system was designed to measure the tension only on expansion anchor bolts. Recent developments and system modifications have permitted measurements on resin-assisted and full-column resin-grouted bolts. The use of these types of support systems has been increasing steadily in underground coal mines.The development of this instrumentation has provided laboratory and field results that help to explain the mechanics and relationships between the applied loads and the interaction between the grouted bolt system consisting of the bolt tendon, grout, and rock."

Jan 1, 1990

By P. Chu, J. A. Finch, R. Li

"Bubble size plays a key role in flotation. In this paper, we examine the possibility of using passive acoustic sending to determine bubble size. Software was developed based on Short Time Fourier Transformation (STFT) to analyze the frequency of the acoustic signal emitted from the bubble formation event. Bubble size was determined from the Minnaert frequency. The acoustic-determined bubble size responded to reagent dosage, but was less sensitive than that given by imaging. The constraints of the current acoustic approach are discussed.INTRODUCTIONBubble size is an important factor affecting flotation performance. It determines the maximum available surface area for collecting and transporting mineral particles. Of interest for process control (Gorain, Franzidis, & Manlapig, 1995), it can be determined by several techniques, such as image analysis (Grau & Heiskanen, 2002; Hernandez-Aguilar, Gomez, & Finch, 2002); conductivity (Barigou & Greaves, 1992); drift flux analysis using gas rate and gas holdup measurements (Banisi & Finch, 1994); and optical sensors (Randall, Goodall, Fairlamb, Dold, & Connor, 1989). However, all these techniques have drawbacks.Acoustic analysis of the oscillatory behaviour of bubbles to extract bubble size is another possibility (Leighton & Walton, 1987; Pandit, Varley, Thorpe, & Davidson, 1992; Al-Masry, Ali, & Aqeel, 2005; Manasseh & Ooi, 2009; Leighton & White, 2012; Spencer et al., 2012). The fundamental basis is the work of Minnaert (1933) who first correlated the bubble size with its natural frequency, Equation 1:"

Jan 1, 2016

By Himmelman. Nicholas P.

In this paper, the hardware foundations and data collection methods of a real time collision avoidance system for electric surface mining rope shovels are described. The primary goal of the system is to help a shovel operator avoid accidentally colliding the shovel?s dipper with either a nearby haul truck or the shovel?s tracks. To achieve this goal, the system requires complete and precise knowledge of the shovel?s geometry and movement, as well as the location of any nearby haul trucks. This paper describes the subsystems created to acquire this necessary information. This system is unique in that all of its components are mounted solely on the shovel and that it is designed to be easily retrofitted to a shovel without significant modifications.

Oct 1, 2009

By T. Gerritsen, T. Plikas, K. Ochoa, M. Loveless, R. MacRosty, J. Reichart, R. Pula

Sidewall accretion in a smelting furnace plays an important role in furnace integrity as it provides protection to the sidewall cooling elements and thereby extends the furnace campaign life. The extreme thermal and mechanical stresses in the furnace and changes in the slag chemistry can cause the sidewall accretion to melt or break away decreasing the lining protecting the cooling elements. Thin accretion is highly undesirable as it increases the risk of exposing the cooling elements to the molten bath and in the worst case may lead to a failure. Therefore, monitoring the sidewall accretion on an operating furnace is extremely important to manage furnace integrity and to support safe furnace operation. Operators often generate estimates for sidewall accretion and refractory thickness using either copper cooler temperatures or heat load into the cooling water circuits. Multivariate statistical models, on the other hand, have the capability to consider all the process measurements simultaneously to provide a more reliable estimate. This paper describes the application of multivariate statistical models for sidewall integrity monitoring on a Flash Converting Furnace (FCF) and also discusses the online implementation of these models as the Sidewall Accretion Monitoring System. INTRODUCTION Rio Tinto’s Kennecott Utah Copper (KUC) smelter located near Salt Lake city, Utah operates a Flash Smelting Furnace (FSF) and a Flash Converting Furnace (FCF) to produce high-grade matte and blister copper respectively. Since the commissioning of smelter in 1995, several improvements were made to these furnaces to increase their efficiency and operational safety. At present, Kennecott smelter is known to be among the lowest-emission and highest energy recovery copper smelters in the world. Since the smelter start-up, Kennecott has invested in several advanced furnace monitoring practices to evaluate the integrity of the furnaces and improve their campaign life. An example is their temperature monitoring system installed for the smelting and converting furnaces, which continuously monitors the furnace sidewall temperatures and notifies the operators during temperature excursions. During an investigation on the converting furnace, it was revealed that there were frequent temperature excursions in the settler sidewall area towards the reaction shaft end of the furnace that caused significant furnace downtime. The reason for the sidewall temperature excursions was not clearly known.

Jan 1, 2019

By Irving Wigden

The world is fast becoming information based. Mine companies migrate business infrastructures to be handled electronically. Suppliers move onto the worldwide web. In this ?e-world? successful suppliers will recognize they no longer trade in just equipment, but in knowledge. Companies can no longer just provide products and services, but instead must find ways to harness their knowledge to provide new value for customers. Mine customers will be attracted to suppliers that can help them streamline the process and use Information Technology to optimize operations, increase profit, reduce cost and enhance shareholder value. With the continued move to industry standard communications and software platforms, technology that formerly stood alone can now be integrated with other technologies. This creates more powerful systems that mine operators can use quickly, easily and cost effectively. These unified architectures improve productivity, provide higher asset optimization and allow more informed decision-making. As a leading supplier of process automation solutions for the industry, ABB provides a dynamic range of such control systems. These systems are designed for instrumentation controls, variable speed drives, electrical distribution, electrical equipment and related services for Mine Automation. Enhanced by ABB´s new family of integrated software solutions ? collectively known as Industrial IT ? ABB´s control and Scada systems place you in the best position to optimize your plant, process and enterprise operations. The paper discuss system integration and installation of High-Tec system in an underground mine. ABB has the ambition to be a System Integrator and co-operate with partners in different areas of technology. To day it is a problem to find one Supplier that can be responsible for the complete Automation System. The design of the system is also much depending of the design of the mine and also which caving procedure that is used in the current mine. Much of the work must be done in a feasibility study and during the design phase. If there is careful planning and consideration during these phases is vital in order to avoid costly changes during the commissioning phase The paper will also include a presentation of the benefit of using Automation in an Underground Mine, and how important the integration of the Human Being is to the Automation System. The most profit gained in mining industries are received when the mines can reduce internal and external disturbances in the production flow and speed. Must of the experience and discussed in this paper is from advanced technology, that has been developed in Scandinavian and adopted of LKAB in Kiruna. The author of this paper has been responsible för the Automation projects in the Kiruna Mine during 1994 - 1999. These projects include: Broadband communication of data, audio, compressed video in one data stream. Control System for Haulage -1045m Automation of Load Haulage and Dumping machines (LHD) Control of Production Drilling Riggs from a Central Control Room.

May 1, 2002

By Irving Wigden

The world is fast becoming information based. Mine companies migrate business infrastructures to be handled electronically. Suppliers move onto the worldwide web. In this ?e-world? successful suppliers will recognize they no longer trade in just equipment, but in knowledge. Companies can no longer just provide products and services, but instead must find ways to harness their knowledge to provide new value for customers. Mine customers will be attracted to suppliers that can help them streamline the process and use Information Technology to optimize operations, increase profit, reduce cost and enhance shareholder value. With the continued move to industry standard communications and software platforms, technology that formerly stood alone can now be integrated with other technologies. This creates more powerful systems that mine operators can use quickly, easily and cost effectively. These unified architectures improve productivity, provide higher asset optimization and allow more informed decision-making. As a leading supplier of process automation solutions for the industry, ABB provides a dynamic range of such control systems. These systems are designed for instrumentation controls, variable speed drives, electrical distribution, electrical equipment and related services for Mine Automation. Enhanced by ABB´s new family of integrated software solutions ? collectively known as Industrial IT ? ABB´s control and Scada systems place you in the best position to optimize your plant, process and enterprise operations. The paper discuss system integration and installation of High-Tec system in an underground mine. ABB has the ambition to be a System Integrator and co-operate with partners in different areas of technology. To day it is a problem to find one Supplier that can be responsible for the complete Automation System. The design of the system is also much depending of the design of the mine and also which caving procedure that is used in the current mine. Much of the work must be done in a feasibility study and during the design phase. If there is careful planning and consideration during these phases is vital in order to avoid costly changes during the commissioning phase. The paper will also include a presentation of the benefit of using Automation in an Underground Mine, and how important the integration of the Human Being is to the Automation System. The most profit gained in mining industries are received when the mines can reduce internal and external disturbances in the production flow and speed. Must of the experience and discussed in this paper is from advanced technology, that has been developed in Scandinavian and adopted of LKAB in Kiruna. The author of this paper has been responsible för the Automation projects in the Kiruna Mine during 1994 - 1999. These projects include: Broadband communication of data, audio, compressed video in one data stream. Control System for Haulage -1045m Automation of Load Haulage and Dumping machines (LHD) Control of Production Drilling Riggs from a Central Control Room.

May 1, 2002

By C. R. Larsen, R. G. Bradburn, A. L. Mular, B. C. Flintoff

"Following the acquisition of grinding- circuit data at Brenda Mines Limited for simulation purposes, various methods to mass balance the circuit were evaluated. Unfortunately, different answers were obtained for different balancing methods. A data-adjustment procedure was therefore developed. The procedure assumes that all ""best-fit"" criterion. A search is conducted with the minimum set of water masses and narrow size ranges of solids around the circuit (called search variables), which permit the computation of any of the measured data points. Search variables are used to calculate measured values for an objective function of the form: [ ] where W, is a weighting factor•, M1 is a measured value and M. is a corresponding . value calculated from search vanables. The best values of M, are those which minimize R. The above method is compared with others that have been utilized for mass balancing circuits."

Jan 1, 1976

By D. Y. Kim

This paper shows an approach that a gondola-typed robot recognizes walls on building facades. It is applicable for autonomous or teleoperated building façade painting robots. The robot may react based on the wall classification data. This approach is based on 2D LRF(two-dimensional Laser Range Finder). The robot acquires relative distances to walls, and a Kalman filter decides correspondence of walls. An ARS(Attribute Reference System) sensor helps convert LRF coordinate to global coordinate. The experimental results demonstrate the conversion of LRF data.

Aug 1, 2013

By Roy EI. Durr, Glen R. Davidge

"This paper presents the results of structural analyses and full-scale destructive tests conducted on liner plate culverts. The purpose of this work was to establish a design method and evaluate the suitability of using these structures in potential roof-fall areas for a rehabilitation application in lower stress and relaxed mining environments. Field evaluation of the design is currently in progress.Theoretical ultimate resistance functions were established for two different culvert shapes and were found to be representative of their experimental behaviour. The ultimate resistance function was used to determine their plastic behaviour to a rapidly increasing deflection condition, to determine the energy absorption capacity of these structures, and to predict their response to impact loading.IntroductionThe Kidd Creek mine of Falconbridge Limited is located justnorth of Timmins, Ontario. The area under rehabilitation for which this program was developed is the 2600 level of the No. I mine. The problem of effectively securing selected drifts at the 2600 level in NO.1 mine, for access to a high-grade ore block, is key to the economics of the operation. Diamond drill test holes had indicated a loosened rock mass above the 2600 level of about 7.5 m thick in response to the extensive mining operation below this level. This level forms the arbitrary boundary between the No. I and No. 2 mines, and has extensive volumes of cemented rock fill below it and largely untouched ore above it to the 2000 level in the North orebody. The walls at that level were showing relaxed ground conditions typical of de-stress: sub-horizontal joints opening up, and peeling.Due to the ground conditions, the consequent safety risks, the high grade of the ore, the potential production delays, and the likelihood of several phases of rehabilitation, regularly used drift rehabilitation employing rock bolts, cable bolting, or shotcrete was not practical. Two options were deemed possible alternatives to suit these conditions, steel sets with blocking and lagging, and liner plate culverts with backfill. Culverts were chosen."

Jan 1, 1995

By Michel David

"The usual complaint of mines is that grade does not match exploration expectations. Quite often, more tons are mined than expected but at a lower grade. This can be seen as dilution. Geostatistics can help predict which dilution can be expected both in terms of grade and tonnage for different mining methods.The usual vocabulary of geostatistics speaks of block distribution; block variance, size effect, information effect, all terms which say very little to the practitioner. In f act, all this can be rephrased in terms of dilution .In this paper, the following is presented - an example which shows how reserves change with the size of selection units and number of samples taken, and tables which show the dilution that are bound to happen when dealing with the commonly encountered log-normal distribution. Finally, the paper shows how grade tonnage computations should be made in the case of an arbitrary distribution. IntroductionGeostatistics progresses more and more rapidly if one judge s by the number and quality of papers published in Mathematical Geology or at APCOM meetings. More and more case studies describing successful applications are published (David et al., 1986)(Kwa and Mousset-Jones, 1987). It is estimated that more than 270/0 of the gold mines around the world use geostatistics. There is still, however, a lot of resistance from the remaining 73%. Geostatistics has more formulae and equations than it needs to reach year 2000. We will be well into the third millenium before all the models available now are actually used. The progress may come in the form of finding better ways to present known statistical results and getting away from the jargon of geostatisticians. One example may be in trying to explain how we can answer the most common plea of the mining industry: production grade is not what was expected in the feasibility study."

Jan 1, 1988

By Gaétan Bourdages

A clarification technology used by municipalities to produce high-quality drinking water, polish sewage treatment plant effluent and handle combined sewer overflows has recently found new applications in the mines and iron and steel industry. This patented process, known as ACTIFLO®, utilizes microsand in a ballasted flocculation process to enhance the settling characteristics of suspended solids, increasing the efficiency sufficiently to achieve a clarifier footprint that is smaller than the one of a conventional clarifier. ACTIFLO® rise rates vary from 40 to 170 m/h with a total system hydraulic retention time of about 10 minutes. The result is a clarification system so compact that a full-scale system can operate as a trailer-mounted unit for temporary applications or as a permanent installation in facilities with space limitations. This paper explains the process and presents case studies in which this innovative technology was used at mines and steelmaking facilities to meet compliance requirements.

Feb 1, 2008