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By John H. Walsh

"ForewordPart I of this paper, published in the March 1992 issue of the CIM Bulletin, surveyed the probable consequences of a limitation on the emissions of carbon dioxide to the atmosphere for the steel industry. What might be termed the conventional responses to this restriction open to the industry were also surveyed in that section. This section, Part II of the paper, explores a new option - the possibility for the joint production of iron and liquid fuels useful for transportation purposes. In this case, it is shown that it is important to minimize the production of carbon dioxide during the reduction stage to maximize the proportion of the reductant carbon embodied in the fuel. It is also advantageous to conserve hydrogen in the reduction step. In essence, the same carbon fulfills two purposes: it serves as a reductant and fuel for ironmaking and then as a constituent of a liquid fuel. If recovered plastics could be used in ironmaking, the same carbon could serve three useful purposes in turn. The conditions and limitations for the joint use of carbon in such 'cascading' processes are explored below. ABSTRACTIt is becoming increasingly probable that emissions of carbon dioxide from the fossil fuels will have to be reduced to deal with the threat of global warming. This issue is likely to be resolved one way or the other in the period 1995 to 2000 which does not leave much time to develop responsive options. In the intervening period, the policy of the Government of Canada is to stabilize emissions of greenhouse gases at their 1990 level by 2000, by encouraging greater efficiency in the use of energy. Should further reductions prove necessary, economic instruments would probably be employed but these would not be applied before a comprehensive international agreement is reached.There are three main themes in this paper: it is assumed that measures to control carbon dioxide emissions will in fact be necessary by the turn of the century; that there will be a rising need for liquid fuels to supply the world's steadily growing fleet of motor vehicles for many years to come, and that the future niche for Canada's industry in such a carbon-constrained world will be the operation of the energy-intensive industries with efficiency and environmental sensitivity.The steel industry, as a large user of both coal and energy in other forms, would be significantly affected by a need to reduce carbon dioxide emissions. This paper first examines what might be called the conventional responses open to the industry in such a situation and then explores a new possibility for making better use of carbon by the co-production of iron and liquid fuels."

Jan 1, 1992

By Rae Simpson

"This paper provides insight into the elements of computerized maintenance systems and identifies some of the factors which influence their effectiveness. The paper describes what to expect in terms of benefits and problems, the nature of effective computerized maintenance systems, some of the systems available and a process for selecting a system for your organization.The paper will be of interest to mining company executives and maintenance or computer personnel who are involved with, or contemplating, the introduction of computerized maintenance systems.IntroductionIn the drive to improve profits in an increasingly competitive world, mining companies are now using some of the most sophisticated equipment available. The introduction of large and complex equipment such as drag lines, haul trucks, and high-capacity milling equipment has resulted in order-of magnitude improvements in productivity. However, this productivity is now, more than ever, dependent on the continued operation of the equipment. A prolonged breakdown of a critical component can have a significant effect on companies' bottom-line results. As more technologically sophisticated equipment is introduced, maintenance costs become an increasingly important factor for mining companies.Fortunately, sound modern management principles are being used more often in maintenance departments. Progressive maintenance managers are turning to computers to help manage the myriad of details associated with running a maintenance organization.Some maintenance departments in larger mining operations would find it difficult, if not impossible, to operate at current productivity levels without their computer systems. Unfortunately, some other companies gain very little from their computerized systems and would probably be better off without them.How can you be sure that computerized maintenance will improve the maintenance picture for your company? What benefits can you expect to achieve? How do you go about selecting a maintenance system for your organization? These are some of the questions facing industry managers and executives today. In the following sections, we will provide some guidelines and insights to help address these challenges."

Jan 1, 1988

By D. A. Barr

"Most of the lode and placer gold production in the Canadian Cordillera has been derived from mines and placers in the Intermontane and Omineca belts. Gold has been produced from rocks of Precambrian to Eocene age, but the preferred host environment contains Upper Paleozoic to Upper Jurassic eugeosynclinal or arc-type sedimentary and volcanic rocks adjacent to plutonic complexes which have a wide variety in both size and composition. Auriferous quartz lodes occur in fissures and shear zones which are commonly subsidiary to strong fault zones. In common with most vein-type deposits, structural complexities are an essential part of the mine environment.Gold production from the Canadian Cordillera to the end of 1978 totals 35.0 million ounces, of which 47 per cent has been produced from placer mining, principally in the Klondike and Cariboo districts. The balance has been derived from lode gold (80 per cent) and base metal (20 per cent) mines.Gold reserves in producing mines and deposits committed for production as of January 1, 1978 were 87.4 tons, or 21.6 per cent of total Canadian gold reserves contained in all types of deposits. Although more than 100 lode mines have operated in the Canadian Cordillera since the turn of the last century, over 75 per cent of the lode gold produced by 1978 was recovered from five mining camps, namely the Rossland, Hedley, Bridge River, Premier and Barkerville.The average grade of the principal producers in these camps was about 0.45 ounce of gold per ton. Individual camps yielded from 3 to 8 million tons during their operating lives, which varied from 28 to 43 years. The last of these mines ceased operating in 1971.Most of the total lode gold production has been derived from quartz veins, frequently with associated carbonate and ankerite, occupying fractured and faulted zones in Mesozoic volcanic and sedimentary rocks closely associated with a variety of intrusions. A review of the literature suggests that several deposits may have evolved by remobilization of ore constituents from earlier concordant gold-bearing formations. The principal metallic minerals in the deposits are native gold, electrum, tellurides, pyrite, arsenopyrite, pyrrhotite, sphalerite, galena and chalcopyrite.As the mineralogy suggests, many of the Cordilleran lode gold deposits have yielded important co-products or byproducts, including silver, copper, lead, zinc, cadmium and tungsten. Significant by-product gold production has also been derived from porphyry copper, volcanogenic, replacement and pyrometasomatic deposits, particularly in recent years.No major lode gold discovery has been made in the past 67 years, although little exploration activity for gold has taken place during the last 30 years. Several relatively small lode gold and gold replacement deposits have been discovered in recent years, either serendipitously (Chappelle) or on very low initial budgets (Northair and Carolin). Based on well-established precedents, one or more of these may eventually be developed into a large mine.A detailed study of the Canadian Cordillera gold deposits based on recent genetic models could prove rewarding, not only in up-dating information on their origin and depositional characteristics, but in stimulating the search for undiscovered gold deposits, in the Cordillera and other parts of Canada."

Jan 1, 1980

Resistance spot welding is the most common type of welding in the automotive industry. In RSW the size and shape of welding nugget is one of the most effective factors on mechanical properties, such as tensile shear strength and fatigue strength. so properly adjusting the variables of the welding is necessary .in this study the effect of different parameters of RSW including time, current, electrode force, geometry of electrode so diameter and angle of electrode tip in the shape and size of welding nugget evaluated. for experimental procedure, low carbon steel sheet st12 is used. the process is simulated with finite element method by using ANSYS software. for the formation of welding nugget a 2 dimensional symmetrical model electrical-thermalmechanical is used and for elevate the accuracy ,we determined the properties of material related to temperature. The results show that increasing the time and current of welding, the diameter of spot weld also increased and the role of current is more impressive. and also increasing the electrode force decrease the diameter of the nugget due to increasing the contact area and decreasing the resistance .increasing the diameter of electrode tip cause increasing contact area and decreasing the resistance and decreasing the diameter of the nugget. furthermore, changing tip angle and electrode diameter don't show sensible change in the geometry of the welding nugget. comparison between simulation and experimental result show a good adaption.

Oct 1, 2011

By J. G. Cullain

In conjunction with the over-all goals of energy conservation at Inco Metals Company, a program of improvement in compressed air utilization was established. Air flows were monitored and compared to calculated requirements to establish efficiency by area. With the cooperation of area management, measures were implemented to reduce nonproductive usage. At the operation, annual savings in power consumption alone were 80,000 dollars. The program is being extended to other mine areas within the Division.

Jan 1, 1979

By Robert D. Brown

"Important tax changes, many of them of direct interest to the mining industry, were contained in the budgets brought down by federal and provincial finance ministers across Canada this spring. This month, Tax Notes presents a brief summary of important tax changes introduced at the federal and provincial levels in the last few months.IntroductionIn the March 1980 issue of the CIM Bulletin, Tax Notes surmised that the short-lived 1979 budget proposals of the former Conservative government offered a unique glimpse of budgetary changes that might be unfolded in 1980. Scene II of this ""now you see it-now you don't"" drama opened on April 21, 1980, when Finance Minister Allen MacEachen, in an ""economic statement""' reintroduced a selection of tax proposals taken from the ill-fated Conservative' budget of December 11, 1979, but refused to bring forward major new proposals in tax and finance.Mr. MacEachen proposed a 5% surtax on federal corporation income tax to apply in the 2 years from January 1, 1980 to December 31, 1981, as a slightly modified version of the same surtax proposed by former Finance Minister Crosbie in his December budget address. Mr. MacEachen also reintroduced a number of technical amendments which would affect the taxation of mining income in certain instances. In addition, a large number of other tax proposals suggested in the previous Conservative budget were also reintroduced, although there are some notable omissions."

Jan 1, 1980

By K. John

"THE most recent estimate of minteable coal reserves in Saskatchewan was made by the Federal Royal Commission on Coal (1944- 6). Saskatchewan was then estimated to have some 24 per cent of the Canadian reserves and two-thirds of this is located in what is called the Souris-Estevan area, which lies in the southeast corner of the Province and border's on the International boundary. It is also estimated that there are some 61/2 million thousand-tons in this area of lignite coal which grades 8,000 B.t.u. or less and has a moisture content ranging from 30 to 33 per cent. Ownership of coal rights in the Province is widely dispersed between the Crown, individuals, and corporations, and a recent survey disclosed that 40 percent of ownership was vested in the Crown and 60 per cent in private individuals and corporations. Coal rights on Crown lands may be leased at an annual rental of $ 1.00 an acre. Under such leases, a royalty of 5 cents a ton is levied on all coal mined. A royalty of 7 cents a ton is levied on coal produced from lands where mineral rights were purchased from the Federal Government prior to the transfer of jurisdiction over natural resources to the Province, in 1931. An annual mineral tax of 50 cents per acre has also been imposed by the Provincial Government on all coals within a defined producing areas."

Jan 1, 1952

By C. Cekerevac

The paper addresses some geotechnical issues related to the construction of the Deriner dam and HEPP. Design considerations and rock stabilization measures are presented for the excavations which took place in a highly fractured and weathered rock mass prevailing on site. Particularly, the shallow excavations for the overflow spillways tunnels are discussed. These present huge openings that are 12 m wide and 18 m high in portal areas, with an overburden of approximately 20 m, for which numerical finite element analysis and structural discontinuity analysis have been performed to ensure safe excavation process and future operation.

May 1, 2009

By Marek Mika

This Paper has been prepared to be presented at the 23rd World Mining Congress & Expo ? Montreal 2013. It presents the idea how to carry out the shaft sinking operation, going through highly water-bearing and very weak rock strata, giving as an example one specific shaft sinking project which is being executed for one of the Polish collieries by our Shaft Sinking Company Content 1. Introduction. 2. Hydrogeological conditions within the area of the shaft. 2.1. Hydrogeological conditions assumed at the stage of designing. 2.2. Hydrogeological conditions encountered in the course of sinking. 3. Designed shaft lining. 4. Procedures for the shaft sinking. 4.1. Designed procedures of the shaft sinking. 4.2. Procedures for preservation and strengthening of the shaft lining and the surrounding rock strata. 5. Technological guidelines for proceeding with the shaft sinking ? selection of special methods. 6. Options for mechanization of work for the selected method. 7. Conclusions.

Aug 1, 2013

By Jean-Francois Magnan

"The old conventional process to produce lithium raw material dates from 1954 (CA patent #504477A). This process produces low purity lithium carbonate (Li2CO3) only. To obtain battery-grade carbonate, another polishing process is needed. To further obtain lithium hydroxide, another chemical conversion process is needed. That is why historically, the value of lithium hydroxide has always been higher than that of the lithium carbonate precursor. With the old conventional process, the low quality lithium carbonate is precipitated from a lithium sulfate solution (Li2SO4) by adding soda ash (sodium carbonate and its impurities). The resulting reaction produces significant quantities of sodium sulfate (salt cake) as a by-product with amounts larger than the impure Li2CO3 recovered with part of the soda impurities. When this conventional process was invented, the salt cake by-product was not an issue: it was discarded in a river near the plant. This practice cannot be done today in North America. While looking to find a solution for salt cake, electrolytic salt splitting of Na2SO4 into NaOH and dilute sulfuric acid appears as a technically feasible solution to get a rid of the salt cake. However, the sodium sulfate salt splitting process has difficulties to economically compete with the chlor-alkali process, which produces millions of tons of NaOH from sodium chloride (NaCl) every year.In contrast, the process developed by Nemaska to directly produce LiOH by Li2SO4 salt splitting not only solves the environmental problems related to the conventional process to produce lithium carbonate raw material, it also produces very high purity lithium hydroxide monohydrate directly at very competitive OPEX cost in comparison with industry peers (Figure 1). It also drastically reduces the amount of reagent and the direct greenhouse gas emissions."

Jan 1, 2016

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 T. L. Carpenter

"The presence of excessive water in the Gibraltar East Stage 1 pit initiated studies into the ground-water conditions that might be expected in mining the Granite Lake and Pollyanna pits. Hydrologic information obtained from a pump test program in 1974 indicated that deep-well dewatering could be successfully achieved. In 1976, a deep-well dewatering system consisting of eight wells was installed on the periphery of the Pollyanna pit . it has been responsible for a significant decrease in mining costs.This paper presents a brief summary of the engineering principles involved in the design of the Gibraltar dewatering system and the problems encountered in the installation and operation of deep-well pumps. IntroductionGibraltar Mines is an open-pit copper-molybdenite mine located approximately 230 air miles north of Vancouver in the central interior of British Columbia (Fig. I). The property consists of three separate major orebodies; Gibraltar East, Granite Lake and Pollyanna (Fig. 2). Mining commenced during the summer of 1971, in the Gibraltar East Stage 1 pit. The Granite Lake Stage 1 pit was mined from mid 1974 to mid 1976. The Pollyanna Stage 1 pit is currently being mined and the Gibraltar East Stage 2 is being developed for production. This report is intended as an outline of the studies and tests leading up to and including the installation of the Pollyanna pit dewatering system, the problems encountered and the results obtained.GeneralIn the summer of 1973, mining in the Gibraltar East pit progressed below ""daylight"" on the down-hill side and ground water very quickly became a costly nuisance in the day-to-day mining operations. Mining, maintenance and blasting costs reflected these problems. Concern was also voiced about adverse effects of ground water on pit wall stability. This concern later became a reality in the Gibraltar East and Granite Lake pits. A study was initiated to investigate various methods and costs of dewatering the pit areas. The study included in-pit sumps, deep peripheral wells and a drainage gallery system located below the pits."

Jan 1, 1980

The Beginning ! The status quo simply isn?t sustainable ! Our social license is at risk ! The bar keeps rising ? We must improve our performance, both operational and social ? We must improve stakeholder judgement of our industry by taking action collectively Implementing TSM " TSM Guiding Principles " Performance Indicators " Crisis communications " External Outreach " Tailings management " Energy management " Performance manuals, guides " Reporting " Communities of Interest Advisory Panel

May 1, 2004

By Sean Dessureault

Technological Revolution ?Information age ? brought about by: ?Low-cost processing, storage, information sharing ?Shared & integrated data ? Increasingly more sensors & data sources From data collection to data use ??Data mining??analyzing the huge volumes of data ?Key example used in MBAs: ?Wal-mart, Google Explosion of data, trickle of information ?Paralysis of action Outline Trying to provoke- What drives innovation now? ?Challenges in mining Data Action Approach ?Examples from research & consulting upon request Conclusions ?Unaddressed challenges (Research Opportunities)

May 1, 2006

By J. H. Baek, S. Alexandrovskii, D. W. Lee, B. K. Kim

Nano-phase titanium carbide was synthesized by Mg-thermal reduction process using a novel route of Mg-thermal reduction. The processes are based on I) feeding of TiC14+CxC14 x = 1, 2 ) solution into liquid magnesium, 2) Mg-reduction of metal chlorides, 3) TiC formation by the reaction of released Ti and C atoms, and 4) vacuum separation of residual liquid phases of Mg and MgCl2. In this study, the process for titanium carbide production with composition close to stoichiometry and the minimum content of impurities was optimized with the various process parameters such as concentration of initial solution, its feeding rate and reaction temperature, as well as a kinetic study.

Jan 1, 2004

By William Petruk

Mineralogical investigations in connection with gold metallurgy are usually performed to find the reason for poor recoveries by cyanidation or by other leaching techniques. Poor recoveries most commonly are obtained when (I) native gold is encapsulated in an insoluble mineral as "invisible gold"; (2) native gold is coated with a precipitate; (3) gold-bearing products are insoluble in cyanide solutions; (4) carbonaceous material in the ore adsorbs gold; and (5) associated minerals decompose and consume cyanide. Samples of refractory material quite often have low gold tenors. It is difficult to find the gold-bearing minerals in such samples with an optical microscope because the probability of finding trace minerals in samples is small. The probability decreases with decreasing grain size of the gold-bearing mineral and with decreas¬ing gold tenor of the sample. Techniques have been developed to increase the success rate of finding gold grains; some are (1) concentrating heavy minerals; (2) preparing special polished sections; (3) searching with an image analyzer; and (4) dissolving associate silicate and sulphide minerals.

Jan 1, 1989

By S. Oppenheimer, P. Au, R. M. Kearsey, J. Tsang, E. McDevitt

A new superalloy, ATI 718Plus® Alloy (718Plus), has been developed to have a 55oC higher temperature capability over the traditionally used Alloy 718, while maintaining favourable processing characteristics and intrinsic raw material costs. The fatigue and dwell-fatigue behaviour of four microstructural variations of 718Plus are evaluated and compared to Waspaloy: 1) standard heat treated condition (HT1), 2) standard heat treated condition with thermal exposure at 732ºC (1350ºF) for 1000 hours (HT2), 3) fine grain condition with a modified d phase (HT3), and 4) fine grain overaged through modified heat treatment (HT4). The results show that the steady-state fatigue crack growth rates of each microstructural variation and both alloys are identical, with all of the 718Plus variations showing a clear advantage over Waspaloy in the fatigue crack threshold regime. Dwell-fatigue results show that Waspaloy has better resistance to crack propagation under dwell conditions; however, optimization of the precipitate phase shows vast improvement in the dwell-fatigue resistance of 718Plus.

Jan 1, 2010

By J. M. B. Scarborough

This paper deals with measures taken to maintain effective operation of heavy-duty equipment in open-pit mining. at Pine Point, N.W.T., during periods of extreme cold weather. The points covered include equipment modifications designed to improve cold-weather performance, effective lubrication of machinery that is vulnerable to extreme cold and operating procedures designed to prevent equipment damage.

Jan 1, 1966

By K. E. Waters, J. E. Nesset, F. Rosenblum, J. A. Finch, S. Moon

"Some materials when exposed to various conditions can exhibit a rise in temperature without requiring an external heat source. Generally referred to as pyrophoric or self-heating substances, they challenge the safety of materials handling, storage and transportation. Reliably assessing the self-heating potential of materials is thus essential. Over the years a number of test protocols have been developed. A widely accepted method is that recommended by the United Nations to certify the safety of shipping pyrophoric goods. Our test work on sulphide materials has shown that the U.N. test can give false negatives if the sample oxidation history is not considered. Depending on the degree of oxidation (“weathering”), the same sulphide material can exhibit self-heating ranging from safe to hazardous. For concentrates, oxidation can occur during storage and transport making the sample weathering history an important consideration in the test work. To make the U.N. test, and other single-stage self-heating procedures, more reliable in assessing self-heating potential when testing sulphide materials, it is suggested that a weathering step be incorporated in the test protocol. This test work for two sulphide samples, an ore and a concentrate, demonstrates the impact of incorporating a weathering stage in the test protocol. INTRODUCTIONSelf-heating occurs when exothermic reactions produce heat faster than can be dissipated to the surroundings. Numerous substances self-heat, ranging from wood chips and powdered milk to coal and sulphide minerals (Beever & Crowhurst, 1989; Hudak, 2002). Mixtures of sulphide minerals, most notably those containing the iron sulphide pyrrhotite (Fe(1-x)S), commonly encountered in the extraction of base metals (e.g., copper, zinc, lead, and nickel), are particularly prone to self-heating (Rosenblum, Nesset, & Spira, 2001; Payant, Rosenblum, Nesset, & Finch, 2012). In the mining and subsequent processing stages, the minerals are progressively liberated and finely ground, then separated, usually by flotation, with the resulting concentrates stored and transported to smelters for metal extraction. At most of these stages the sulphides are exposed to both moisture and oxygen, conditions that promote partial sulphide oxidation and the formation of elemental sulphur. Studies have shown that pyrrhotite, in particular, readily oxidizes to form elemental sulphur (Bernier & Li, 2003; Belzile, Chen, Cai, & Li, 2004; Somot & Finch, 2010). The elemental sulphur becomes fuel for further self-heating as the temperature of the mineral mixture increases above 100 oC (Rosenblum & Spira, 1995; Somot & Finch, 2010). It is believed the propensity of pyrrhotite to self-heat is a result of its iron-deficient, and hence somewhat unstable structure. It is worth noting that pure metal sulphides (with the exception of pyrrhotite) do not exhibit appreciable self-heating. A mixture of minerals sufficiently different in their electrochemical rest potential is required to initiate self-heating at ambient temperatures (Payant et al., 2012)."

Jan 1, 2016

By M. Saghaeian, R. Hejazi, Sheikhzadeh. V., A. Abazarpoor

"The morphology of iron ore concentrate particles is known to influence several properties of iron ore pellets, including drop number, compression strength, and reduction properties. This study aimed to determine why grinding methods and particle morphology influence green pellet properties. Particle morphology can be directly related to the grinding method: ball mill (BM) or high pressure grinding roll (HPGR). In this research, two iron ore concentrates, namely Gol-e-gohar and Ardakan, were ground by a BM and HPGR to produce a suitable Blaine value for pelletizing (nearly 1,900 cm2/g). Morphological features of particles were subsequently investigated by sieving and cyclone sizing for particle size distribution, the Brunauer-Emmett-Teller (BET) and Blaine methods for specific surface area (SSA) and scanning electron microscopy (SEM) for the evaluation of shape descriptors. It was concluded that HPGR resulted in generating a greater proportion of fine particles compared to ball milling. The BET results showed that the SSA of HPGR pellet feed was higher than that from the BM due to a greater proportion of cracks, indents and bulges and the creation of new fracture surfaces. SEM images processed by ImageJ software indicated that particles ground by the BM tended to be more rounded and less elongated than HPGR particles because of the breakage model of each method. To show the effect of morphology on the green pellet quality, green pelletizing was performed in a pilot pelletizing disc. The HPGR pellet feed had a higher drop number in comparison to the BM pellet feed, due to the angular and rough shape of the particles.INTRODUCTIONThe demand for fine or ultra-fine particles as feed material for ceramics, composite materials, and mineral processing is on the rise (Kotake, Kuboki, Kiya, & Kanda, 2011). The final concentrate of iron ore processing plants (filter cake) has a size range roughly between 0 and 300 µm, depending on the liberation of Fe containing particles (Meyer, 1980). In general, to produce a suitable pellet feed of appropriate quality, Blaine numbers of 1800–2000 cm2/g should be achieved (Van der meer, 2015)."

Jan 1, 2016