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By S. Kaushik

The control room in a mineral processing plant has become increasingly complicated with complex unit operations coupled with rapidly evolving systems of sensors and control. Even with significant automation, human intervention is required to counter various scenarios that play out every day. A typical control room operator must monitor over 300 individual points of data in order to ensure the safe and efficient operation of the plant. At the same time, the experience of the workforce is decreasing as operators retire and the new generation enters the concentrators. Global competition for skilled operators continues to be strong and the opportunity to apprentice has diminished. The challenge is to provide a skill foundation for the operators so that they can be effective in the concentrator in a timely and safe manner. Progressively, the industry is turning to dynamic simulation tied into the control system. The simulator environment operates behind the control system to emulate the plant operation, reacting as the plant would when a change is made. The operator drives the process, with realistic feedback, which enables learning in a safe environment. This paper will take the reader through a green-field case study and discuss the effectiveness of integrating an operator training simulator (OTS) on the operator’s learning curve.

Jan 1, 2014

By S. Simukanga, J. Masinja, P. A. Bepswa, A. N. Mwale

Screening is an important operation in dry and wet closed circuit mineral processing applications. Most of the operations have seen the benefits of using fine wet screens in primary grinding sections where the product is relatively coarse, and screens can handle the tonnage. Although many models are available, most of them are confined to dry and wet coarse screening applications. Most models do not give good predictions for wet fine screening. To facilitate model development, pilot plant tests were performed using a single deck Derrick Screen at aperture sizes of 45µm, 75µm, 106µm, and 150µm. Experimental data for a range of feed solids concentrations and flowrates was collected and used to calibrate the performance of the screen under the different operating conditions. The results showed that the performance of the screen deteriorated with an increase in feed solids concentration, and, similarly with an increasing feed flow rate. The percentage of fines carryover also increased with the reduction aperture size. The carryover was even more pronounced at higher feed rates and solids concentrations. A model was developed for predicting the performance of fine wet screening. Data from the test work was used to compare the actual and predicted results, and to calibrate the model. Additional independent data was used to validate the model and assess its limitations. This model will give an expected screen performance based on the initial feed conditions. It incorporates screen design parameters that allow for an estimation of a suitable screen size for a desired performance based on given feed conditions. This paper discusses; the results from the test work performed, the model development and its limitations.

Jan 1, 2016

By M. Roy, Y. Roux, R. McIvor

"La Compagnie Minière Québec Cartier at Port Cartier. Quebec, utilizes six parallel wet grinding open circuit ball mills to grind iron ore concentrate for the pellet making process. In an attempt to improve grinding efficiency, a mix of 605 25 mm (1 in.) and 405 38 mm (1 ½ in.) grinding balls was charged to mill D while the opposite mix was used in all the other mills. Because media costs were higher for mill D, it was necessary to find out if the smaller balls provided a net economic benefit. Therefore, a test program was undertaken to determine the relative efficiency of the charge in mill D compared to the other grinding mills. Mill F was chosen for comparative efficiency measurements.The first problem was to choose a suitable definition of grinding efficiency. In management's view, previous attempts to quantify milling performance using population balance modelling were ineffective because they were unable to relate breakage rate functions to grinding circuit economical in any meaningful way. Work index analysis was also not favoured because of a number of complicating effects, including the fineness of the feed and product streams and open circuit grinding.It was decided to adopt a recent innovative approach which had been successfully applied to closed-circuit ball milling. For ""functional performance analysis of ball milling"" (McIvor et al., 1990; McIvor et al., 1991), a size criterion is first chosen to define ""fines·' and ~'coarse particles"". In this case 45 microns (325 mesh) was chosen to distinguish fines from coarse material. The relative grinding efficiency of each ball mill environment would then be ~e cumulative grinding (disappearance) rate of coarse (plus 45 nucrons) material per kilowatt hour of energy applied to the coarse material in the mill, divided by the grindability (measured in the laboratory) of the coarse material in the mill feed.Because the disappearance rate of coarse particles is also the production rate of fines, the following equation can be written for the efficiency of the mill environment, Effe, as defined above:"

Jan 1, 1994

By K. Kawagishi, K. Matsumoto, Y Koizumi, H. Harada

A new burner rig for cyclic and hot corrosion testing of Ni-base superalloys and high-temperature coatings has been developed at the National Institute for Materials Science (NIMS) in Japan. The concepts of the rig design include: use of kerosene as fuel, easy operation for materials research and multi-specimen testing capability per test run. The burner rig consists of six blocks including combustion block, corrosion-solution injection block, furnace block, specimen block, controller block and outdoor facility block. During verification testing, it was confirmed that the rig had accurate specimen temperature control within ±1? from 600 to 1100? and automated easy operation. Cyclic testing of several Ni-base superalloys was conducted. The results from 50 cycle testing indicated that a new NIMS alloy developed for 1700? class gas turbine had higher oxidation resistance than CMSX-4. This new burner rig testing capability at NIMS can be very useful for future oxidation, hot corrosion and coating durability studies.

Jan 1, 2010

By W. J. Stickney

"Over-all recovery of cadmium has been increased at the plants of the Hudson Bay Mining and Smelting Co., Limited, since the construction of a slag fuming plant and baghouse where smelter flue dust is recovered. This pa-per outlines the distribution of the cadmium in plant products from the concentrator to the refining department.The leaching of cadmium-bearing precipitates from the zinc plant is also discussed. This consists of a two-stage leach; first with sulphuric acid and then with copper sulphate. Details of the leaches are outlined along with the safety measures practised in handling the hydrogen and arsine evolved.The paper describes the final preparation of electrolyte for the refining cells by purification for copper and thallium. Deposition of cadmium, using a polyacrylamide as an addition agent, is discussed.An outline is given of the melting procedures, under either sodium hydroxide or zinc chloride, and of the sub-sequent treatment of the dross to recover entrained cadmium and thallium."

Jan 1, 1966

By David McMullen

Radiation plays a critical role in the thermal behaviour of hydrometallurgical process equipment. This effect is particularly important when designing refractory lined equipment used in pressure leach/oxidation processes. In order to simplify this non-linear mode of heat transfer, the effects of radiation had previously been incorporated in an equivalent convective film coefficient in finite element methods (FEM). This prior method omits the effects of radiosity, a critical aspect of radiation heat transfer, which affects the design of refractory lining systems in autoclave vessels. Given that 60% of the heat loss in actual plant practice of an autoclave is due to radiation, reliability in the FEM is therefore impacted. This study validates the use of radiosity in FEM through thermal loading using a combination of simple geometries to be applied to complex environments such as vessel nozzle clusters. The added benefits of using a radiosity load includes an increase in confidence in thermal distribution results, greater accuracy in determining appropriate refractory lining systems, weld overlay sizing, and increased accuracy in structural analysis.

Jan 1, 2014

By Christopher Riley

A relatively unexplored lead zinc deposit lies about 12 miles northwest of Revelstoke, B.C., in the highly metamorphosed Monashee Group of rocks of the Shuswap Terrane, Precambrian in age. Host rocks are of sedimentary origin and consist of gneisses, schists, marbles and quartzites with intermediary types. The marbles and quartzites provide good horizon markers. Using these it is possible to interpret the controlling structure which is a syncline overturned to the north, dipping south at about 45°, and plunging east at about 12°. The syncline is truncated at about halfway of its length on a peak on the west side of which a partial cross section together with superimposed minor folds may be seen. The quartzites and the two marble beds may be traced over much of the structure. There are two lodes, above the marble and below the quartzite, which converge eastward and which are the exposed edges of the same host bed -an impure limestone.

Jan 1, 1961

By DALE MacGREGOR, VERA TUREK

The Blue Mountain nepheline syenite deposit has been the subject of several detailed studies. It has been variously referred to as an intrusive stock, a metasomatic deposit, an intrusive sill and a metamorphic-metasomatic body. The body is divided into six mineralogical zones, the first five being based on the characterizing accessory mineral; muscovite, muscovitemagnetite, biotite-muscovite, biotite, hornblende and pink syenite. Mining currently takes place only in the biotite zone. Foliation is particularly prominent in the central (hornblende) zone and near the margins of the nepheline syenite. Majic bodies within the nepheline syenite may represent basic rocks that have been less altered by metasomatism, metamorphosed basic dykes or sloped blocks of metasediments. The most prominent structural features are the northeast-trending folds that have been modified by later north west-trending folds.

Jan 1, 1984

By P. Homola, M. Karlík, M. Slámová

"Aluminum sheets (AA1199, AA8006, and AA5754) were processed by accumulative roll-bonding (ARB) in the temperature range from 20 to 350°C. The microstructure of the sheets was characterized by means of scanning and transmission electron microscopy and electron backscattered diffraction. Mechanical properties were monitored by hardness measurements and tensile tests. Increasing strain (number of ARB cycles) led to incremental development of lamellar microstructure with a decrease of the spacing between high-angle grain boundaries in the normal direction of sheets. ARB process produced an important increase of strength while maintaining thickness and relatively high ductility, without accenting of the anisotropy of mechanical properties of sheets. The level of hardening decreased with the processing temperature and at 300 and 350°C ARB caused even the softening of the material due to the recovery of the deformed microstructure or partial recrystallization during heating to ARB processing temperature.INTRODUCTION Accumulative Roll Bonding (ARB) is a technique of grain refinement by severe plastic deformation (SPD) proposed by Saito et al. (1999). One ARB cycle consists in sheet cutting, surface treatment, stacking of two pieces, heating (optional), and rolling with 50% reduction in thickness. Since the sheet thickness remains unchanged by this cycle, ARB processing can be repeated as many times as desired. The goal of ARB is to impose an extremely high plastic strain on the material, resulting in structural refinement and strength increase without changing specimen dimensions. After several cycles, ultra-fine grained (UFG) materials with high strength and relatively high ductility are produced. An advantage of this method is that it does not require any special equipment as other SPD methods such as equal channel angular pressing (ECAP) (Valiev & Langdon, 2006), high pressure torsion (HPT) (Valiev et al., 2000), or cyclic extrusion and compression (CEC) (Richert et al., 1999), but only a conventional rolling mill and so it is seen as an economically viable and industrially scalable processing route. ARB processing has been successfully applied to various kinds of metallic materials at room or elevated temperatures (Tsuji, 2005). Besides processing single metals and alloys, ARB has also been used for creating ultra-fine grained and nanograined metallic composites (Wu et al., 2010; Qu et al., 2014)."

Jan 1, 2018

By L Thompson, R C. West, T S. Kho

In 1978, the Outotec direct to blister flash (DBF) smelting process was commercialized with the commissioning of the Glogow 2 smelting facility in Poland. Since then four further DBF facilities have been constructed, two at Olympic Dam, one in Zambia and most recently one at Glogow 1 in Poland. The DBF smelting process differs considerably from conventional smelting process in both chemistry and unit operations, presenting opportunities for flowsheet capital and operating cost savings particularly when the concentrate copper grade is high. WorleyParsons has amassed considerable expertise in the Direct to Blister process and in this paper the process is compared to the modern two stage Double Flash process. The processes are modeled, and the key operating parameters, consumables and production metrics are directly compared. Subsequent flowsheets, key equipment lists and capital costs are also presented for comparison and discussion. The results show the range of concentrates which are most economically treated by the DBF process relative to those best treated in conventional processes along with those concentrates which could be treated by either process. INTRODUCTION The Outotec Direct to Blister (DBF) process was developed and installed at Glogow in 1978 (Czernecki et al., 2006). Currently there are a total of five DBFs built on three sites: Glogow No.2, Olympic Dam No.1, Olympic Dam No.2, KCM Zambia and Glogow No.1, being the most recently constructed. The DBF process was the first flash furnace process to produce blister copper and paved the way for the subsequent development of the flash converter and other continuous converting processes. Today four flash converters are in operation taking the total number of flash furnaces producing blister copper to eight. In all DBF operations it is the unique ore and concentrate composition which made selection of the DBF process the most attractive. In all cases, the concentrate is relatively high in copper but low in iron because chalcopyrite is not the major constituent. When considering smelting options for high copper, low iron concentrates a key question is then often asked, “At what point does it become economic to switch from two stage smelting and converting process to the DBF process?”

Jan 1, 2019

By P. Mattar

The geotechnical importance of studying fluid flow through porous media and soils in particular, becomes evident when dealing with groundwater movement in surficial geomaterials that can be initiated by hydraulic gradients that develop during construction activity, groundwater extraction, impounding of reservoirs and groundwater recharge during adverse climatic events. In a geotechnical context, rocks are regarded as virtually impermeable materials, with comparatively greater resistance to flow of water through their pore structure. The importance of the permeability of rocks comes to the forefront when deep geologic formations are used in geoenvironmental activities for disposal of hazardous and toxic materials. The permeability of the rocks encountered is of critical importance to these geoenvironmental activities since the movement or transport of the hazardous materials during their eventual release will be largely governed by the permeability characteristics of the geologic formation. The estimation of the permeability characteristic of geologic formations is a non-trivial exercise since the measure of permeability can be influenced by the scale at which the measurement is made. Regional-scale and borehole-scale estimates of the permeability can be greatly influenced by the inhomogeneities, including fractures, fissures, solution channels and other anomalies that are present in naturally occurring geologic media. These anomalies are considered to be site specific and can only be determined in a reliable fashion by either conducting tests at the appropriate scale or in the regional-scale through inverse analysis of tracer movement patterns in rock masses. The estimation of the permeability of intact units of a geologic medium has important geoenvironmental applications in connection with storage of wastes since the units in which repositories will be located should be sparsely fractured and the sealing of the fractures and fissures are a prerequisite to developing an efficient solution for storage. The intact permeability of geomaterials is therefore regarded as an important property that influences efficiency and reliability of geoenvironmental solutions for deep geologic disposal. The permeability of geomaterials such as concrete and cementitious grouts are also important to many geoenvironmental and infrastructure applications where durability of structural materials in general and cements used for sealing deep boreholes and other access shafts employed in waste management endeavours is influenced by the permeability characteristics of these materials

May 1, 2009

By S. Perkins, E. Young, L. Dufour, K. McVey, L. Rolandi

This paper presents a review of plant layout considerations incorporated into recent designs of SAG/Ball mill circuits for two medium sized concentrators. The plant layouts presented and the design concepts discussed, relate to smaller SAG circuits, but can equally apply to larger milling circuits. Included are design concepts and ideas introduced by the various project teams, and the focus is on the primary factors of any layout design which are safety, constructability, operability, and capital cost.

Jan 1, 2012

By A. L. Hinde, H. Dong, J. T. Kalala

"The High Pressure Grinding Roll (HPGR) is gaining acceptance in the mineral processing industry and has become a competitive technology in reducing the specific energy consumption in Mineral processing plants. The amount of samples required for HPGR amenability testwork and HPGR wear tests is usually high and often cannot be available at early stage of projects were only a few drill cores are available.Although HPGR was initiated from small scale piston die compression tests, the development of small scale piston die test to predict the performance of HPGR has been slow.The objectives of this paper was to present the designs, operating procedure of piston-die press and operating conditions which have resulted in similar particle size distribution obtained from a piston die test and HPGR Labwal unit starting from the same feed size distribution. Testwork were conducted using a 2 MN piston-die press and a Labwal HPGR unit on major South African ore types, viz, gold, platinum and iron ores. The results obtained show that piston-die test can generate data to predict energy consumption, product size distribution, and even to evaluate the edge effect."

Jan 1, 2012

By Gordon L. Kidd

The object of this paper is to show the relations of the East Coulee coal area to the near-by Willow Creek, Wayne, Rosedale, and Drumheller areas, all being parts of the Drumheller field. The word ?area? is here used in a more local sense than that employed by Dr. J. A. Allan, whose. 'area' is rather comparable with the 'mining division' in British Columbia. I have drawn freely from the published information, particularly from Dr. Allan's report on the "Geology of Drumheller Coat Field, Alberta", and from Dr. E. Stansfield's paper on " A Chemical Survey of Alberta Coals", to whom thanks are due. The Drumheller field is served by branch lines of the two principal Canadian railways. The C.N.R. traverses the district by its Goose Lake line from Calgary to Saskatoon; and the C.P.R. by a line from Calgary to Acme and then southeasterly to Drumheller, where it effects a junction with the C.N.R., over which the C.P.R. has running rights as far as Rosedale. From Rosedale, a joint line built during the summer of 1928 extends about forty miles down the Red Deer river to the mouth of Bull Pond creek. From that point the C.P .R. turns more southerly to connect with the Bassano-Empress line. The C.N.R., it is expected, will eventually proceed eastward to connect with a transcontinental line. The joint line from Rosedale down the Red Deer river opened up the Willow Creek and East Coulee areas.

Jan 1, 1929

By S. Banisi, M. Maleki-Moghaddam

Direct observation of charge shape and its motion in industrial mills is not possible; therefore, a combination of analytical and physical studies is used to determine charge trajectory. Software packages, which predict charge motion consider only the outermost layer of charge (single ball) and ignore the charge and the interactions of grinding elements. In the new version of the GMT (Grinding Media Trajectory) software, the effect of liners specification and bulk load on charge shape and trajectory are considered. The charge trajectory was measured in a laboratory mill with the diameter of 100 cm and length of 21.5 cm with the transparent end and compared with that of the old version of GMT. Four types of polyurethane rings were accurately machined to scale down the liners arrangements at two industrial mills. The model mill was operated at 55, 70 and 85% of the critical speed for five levels of mill filling (10, 15, 20, 25% and 30% by volume). The experiments indicated that the end walls effect was negligible for the model mill with the length of 10.8 cm and beyond. The proposed relationships to correct the trajectory and charge shape were validated by using the new liner of the Gol-E-Gohar iron ore company AG mill. The positions of shoulder, toe, toe departure and impact points were predicted with the relative errors of 5, 0.7, 2 and 0.2%, respectively. The GMT software was updated with the new relationships. The results of GMT simulation indicated that when the lifter face angle increased from 7 to 30°, the distance between the charge impact point and the toe decreased from 40.1 to 11.2° for 30% filling. The change in the position of the impact point meant increasing the probability of charge impacting the toe, not the liner which favored more efficient comminution practice.

Jan 1, 2016

By F. H. Samuel, P. Burke, F. Mucciardi, J. Gruzleski, S. A. Musmar

A new thermal analysis technique has been developed and tested. It utilizes the enhancement in heat transfer characteristics associated with a recent advancement in heat pipe technology. Heat is extracted from a liquid sample of a melt taken in-situ within a vessel or furnace. The rate of heat extraction is such as to cause the sample to solidify. The technique was tested in both laboratory scale and industrial scale (Grenville Castings, Perth, Ontario). A 356 Al Alloy, subjected to various melt treatments was used to perform the tests. Classical thermal analysis was also performed simultaneously using a preheated graphite cup and at the same melt conditions. The comparison showed the potential of the new technique over classical thermal analysis. The major advantages of the new method are that it conducts the analysis inside the melt (i.e. a physical sample is not removed from the melt), it consumes less time and the cooling rate can be precisely controlled during the solidification process. Moreover, the resolution of the results is better than that of conventional techniques. Aluminium

Jan 1, 2006

"ChairmanThis part of the discussion is intended as an exchange of information between those who have installed rubber liners in their mills and a means of others to get information that may help them decide if rubber liners would be applicable to their mills.To start the discussion and to relate it to the previous section of this symposium Mine Equipment Co. Ltd. have supplied some graphs that will give some idea of the noise suppression that may be expected from the u.se of rubber liners instead of steel. The figures used in preparing the graphs came from installations of rubber liners in Sweden.L. Strah - Mine Equipment Co.The graph, Figure 1, shows on the bottom the octave band range. The noise level generated by the steel liners is represented by the dotted line and lies within the shaded area where it is considered that hearing damage may result. The solid line represents the noise level generated by rubber liners in the same mill and you will see it is below the shaded area. Although it is not marked on the graph I think the decibel range is from 7 5 to 115. The next one, Figure 2 which shows the relative noise levels generated by steel balls and pebbles with both steel and rubber liners shows the decibel range."

Jan 1, 1968

By A. Noël, R. Lapierre, M. Provencher

"Modem aluminum smelters are facing significant operating cost pressure. Key methods used by smelters to manage this pressure are automation and production-information systems to optimize processes, manage quality, anticipate problems and reduce operating costs. In 2002, Aluminerie Alouette Inc. began its Phase II Expansion project, and retained the joint venture of SNC-Lavalin and Hatch (SLH) as its engineering, procurement and construction management (EPCM) team. Alouette had the distinction of being one of the most efficient aluminum smelters in the world. Alouette already understood the importance of systems integration in project delivery. For Phase II, key objectives were identified to ensure ""a state of the art"" integrated architecture that would support Alouette's production goals to integrate the existing facilities with the expansion, to form a single efficient facility and meet project schedule and budget targets. Achieving those objectives within the context of a large project often creates major challenges due to the nature of the traditional EPCM delivery model, which relies on several vendors and third-party-systems integrators. In this case, an integrated Alouette-SLH team was made responsible for all aspects of the systems integration, taking over the task from most suppliers. The integrated team was responsible for delivering an automation system and plant-wide-production IT system for the new facilities while accommodating migration for the existing systems. Through the use of rigorous methodology and advanced state of the art technology, the IT and automation strategy led to significant value creation and is recognized today as one of the key factors of the project's success. The primary results were: fast and efficient start-up of facilities, due to quality programming and implementation; a plant able to operate as a single entity; automation and IT systems delivered before time and under budget; standard programming methods implemented throughout the plant; and reduced and simplified maintenance."

Jan 1, 2006

By Colin Jones

Canadian Clay Products Inc., which mines bentonite in Saskatchewan near Truax and operates a plant at Wilcox, is the sole producer of swelling bentonite, often called western bentonite, in Canada. Seven products produced by the company are used in binders, sealants, water and waste water treatment, plasticizing agents, foundries and absorbents. Reserves are reported at about one million tonnes for the deposit but the area in general contains significant additional reserves.

Jan 1, 2001

By R. E. Phelan

Introduction The Flin Flon deposit was discovered by Tom Creighton, an experienced prospector and trapper, who in 1914 made his headquarters at The Pas, Manitoba, and still lives there. The discovery was made in the fall of 1914, and Creighton and his associates spent the next summer in investigating the find. In August of 1915 the first claims were located. The property was optioned to Hayden Stone & Company, and in the spring of 1916 they started a diamond-drill campaign. Hayden Stone spent $50,000 on the property and, among other things, completed over 7,500 feet of diamond drilling. The ore not being as high grade as expected, and also being complex in character, Hayden Stone then abandoned their option. In the spring of 1917, Messrs. Earle, Faskin and associates took an option on the property and started an extensive drilling campaign. This campaign accomplished approximately 18,000 feet of drilling and secured for the Faskin interests a 32 per cent interest in the property. In 1920, W. B. Thompson and The Mining Corporation of Canada secured an option, and, while this option was in force, sunk two shafts in the ore-zone and did a considerable amount of drifting and cross-cutting in the ore to study the manner in which it occurred in place, and, by actual channel sampling, to check the grade indicated by the previously accomplished diamond drilling. All of this work had indicated that an ore-body existed on the property containing at least 18,000,000 tons of ore, assaying as follows: gold, 0.074 oz./ton; silver, 1.06 oz./ton; copper, 1.71 per cent; and zinc, ). 45 per cent (1). Complete analyses of composites from the drill holes showed that the ore was very complex in character. It contained the above values in gold, silver, copper, and zinc, as well as large amounts of sulphur and iron, and traces of lead, arsenic, antimony, cobalt, and various other metals. Although the ore was obviously pyritic in character, pyritic smelting, the usual method of treating this class of ore, could not be used to beneficiate the ore with any reasonable expectation of making such a venture a financial success, since coke and coal landed at Flin Flon would be expensive, and siliceous flux was known to be scarce locally and low in grade. The property therefore lay idle until 1925.

Jan 1, 1935