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By W. S. Tremaine

When the Hedley Mascot mill was built in 1935, it was designed as a straight flotation plant. The ore to be treated at that time was a gold ore in which the gold was intimately associated with arsenopyrite and pyrrhotite in highly silicified and garnetized limestone gangue. This material was ground to 85 per cent minus 325 mesh in two-stage grinding and floated in standard flotation cells to produce about a 5-ounce concentrate, which was shipped to Tacoma smelter for refining. This arrangement gave us a recovery of about 89 per cent. Test work indicated that the best way to improve this recovery would be to build a cyanide plant to treat our flotation middling. Arrangements for the construction of this plant were finally approved and work on it was started in the spring of 1940. This plant was of the conventional type in which the flotation middlings were thickened, filtered, and then put through the usual cyanide process. Its capacity was 50 tons of middlings per day. This arrangement worked quite satisfactorily and gave us an increase in overall recovery of 4 per cent. Unfortunately, about the time the plant was completed, we developed, and started to ship to the mill, ore that differed entirely from that met with up to that time. Instead of being hard, it was very soft, the orebody from which- it came being much faulted and brecciated. In many sections, the sulphides were oxidized and the breccia was filled in with a very soft, hydrous iron silicate known as chloropal. When this new ore was mixed with the old ore and sent to the mill, the whole operation was disrupted. The chloropal slimed so badly that the classification, flotation circuits, and cyanide plant would not handle it. The difficulty in the cyanide plant was at the head end, where the 10 ft. by 20 ft. thickener and the 8 ft. by 8ft. drum filter would not handle the middlings containing a large percentage of primary slime and chloropal. This material would not thicken to more than 30 per cent solids in the thickener and, when pumped to the filter, would forma very thin, slimy cake. Overall recovery dropped to between 83 and 84 percent and it was quite apparent that some extensive changes would have to be made in our flow-sheet before this ore could be treated successfully.

Jan 1, 1947

By R. L. Bruening, N. E. Izatt, S. R. Izatt

The need for selective metal separations has increased as the mining industry encounters more complex ore bodies and demand for higher performance end products expands. The Molecular Recognition Technology (MRT) process uses highly selective SuperLig® resins to remove desired metals from a variety of solutions in the mining and metals processing and recovery industries. MRT separation processes efficiently produce high purity metal products. In this paper, applications of MRT to metal recovery at mg/L to multiple g/L concentration levels are presented and discussed. Specific examples in the precious metal, nickel, cobalt, zinc, copper, and rare earth industries are given.

Jan 1, 2014

By David Runnels

The Mount Wright iron are mine and upgrading plant were brought on line in the fall of 1975. The mine is located near the Quebec - Labrador border some six hundred miles northeast of Montreal. This paper describes the crushing, grinding and concentrating facilities at Mount Wright, and some design: criteria used in equipment selection and flow sheet design. Also mentioned are some "asbuilt" modifications. A brief description of the over-all flowsheet is also included. Introduction IN SEPTEMBER 1970, the Quebec Cartier Mining Company started development of the Mount Wright iron ore mine. The estimated are reserve is in excess of 1,000,000 ,000 long tons of concentrates, with an average crude are grade of 31.5% Fe. The run-of-mine ore is crushed, ground and concentrated to a product having 66% Fe and 5% silica at an annual concentrate production r ate of 18.4 million long tons. The daily production rate of over 50,000 long tons of concentrate necessitates a daily mine output of approximately 250,000 long tons of material, of which 50% is waste.

Jan 1, 1977

By Ross I. Kelly

Carbonate rocks are widespread throughout Ontario and provide raw material for more uses than perhaps any other rock type. The principal carbonate rocks that are used by industry in Ontario are Paleozoic era limestone and dolostone. Limestone is a sedimentary rock that is composed mainly of the mineral calcite (CaCO,) while dolostone, also a sedimentary rock, is composed mostly of dolomite [CaMg (CO,),l. The majority of the province's limestone and dolostone extraction occurs from Paleozoic era rocks located in southern Ontario. Calcite and dolomite are also found in Precambrian marbles, calcite veins and carbonatites, however, utilization of these rocks by industry has been less common. Calcite and dolomite-rich rocks are utilized for a wide variety of uses including raw materials for cement and lime manufacture, chemical and metallurgical stone, fillers and construction aggregates (Derry, Michener, Booth and Wahl and OGS 1989a). For some uses chemical and physical requirements are very important. In the manufacture of glass, for instance, the chemical requirements of source materials are very important and very stringent. In other uses physical criteria such as whiteness may be more important. Although carbonate rocks are quite plentiful within the province, deposits that contain high concentrations of calcite or dolomite are somewhat limited. For that reason, this paper focuses on deposits that are known to, or may contain, a high percentage of calcite and/or dolomite. The paper emphasizes potential sedimentary limestone and dolostone resources, as these are the carbonate rocks most commonly utilized by industry in Ontario.

Jan 1, 2001

By J. Gray, J. Peck

As the turn of the century approaches, traditional open pit mining methodologies and processes are being modified through the introduction and use of new technologies. As in other industries, the personal computer is dramatically changing the traditionally conservative mining industry by allowing mines of varying size and capacity to increase their productivity and efficiency through the use of easy to use, office software. Computer-based monitoring and control systems are also being used more frequently to measure and optimize, in real-time, the performances of operating equipment. When communicated to an end-user, this information can provide accurate and timely answers to questions of how much, where, when, and by whom. This capability forms the foundation of a more comprehensive, proactive management and planning facility where, ultimately, information acquired from the producing equipment will be used to optimize and control machine and human activities. As these technologies mature and become essential tools in a mine, they will eventually serve as the basis for more robotic and autonomous mining operations.

Jan 1, 1999

By R. T. Erskine

"The No. 6 orebody is located 6 miles from the main op.eration of Brunswick Mining and Smelting Corporation Limited and includes open-pit and primary gyratory crushing facilities. Ore is transferred by truck to the secondary crushing facility at the main plant. About 3,500 tons of ore per day are crushed to minus % in. and ground to 68 per cent minus 400 mesh in rod and ball mills for flotation feed. Conditioning and aeration precede rougher flotation, and four stages of cleaning bring concentrates to a grade of 42 per cent Pb + Zn + Cu. Middling products are reground and refloated in a secondary flotation circuit, producing a cleaner feed and a final tails product. Primary bulk concentrate is treated with sulphur dioxide and steam-heated to l 70°F and the majority of the gangue is floated off, leaving a product that assays 57 per cent combined Pb + Zn + Cu and is suitable for marketing. This material is thickened, filtered, dried and loaded into railway cars for shipment to the smelter. Reagent use on flotation is conventional, with many compromises in dosage required to maintain the recovery of lead and zinc in the most advantageous proportions. Many refinements in the flowsheet have been made since start-up in 1966, and more may be made as laboratory and plant testwork indicate possible improvements."

Jan 1, 1971

By F. J. Hrach, K. P. Flynn, P. J. Miranda

"ST Equipment & Technology, LLC (STET) has developed a processing system based on tribo-electrostatic belt separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. In contrast to other electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the triboelectric belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (300 µm) particles with very high throughput. The high efficiency multi-stage separation through internal charging/recharging and recycle results in far superior separations that can be achieved with a conventional single-stage free-fall tribo-electrostatic separator. The triboelectric belt separator technology has been used to separate a wide range of materials including mixtures of glassy aluminosilicates/carbon, calcite/quartz, talc/magnesite, and barite/quartz. Separation results are presented for selected industrial mineral sources. An economic comparison of using the tribo-electrostatic belt separation versus conventional flotation for barite / quartz separation illustrates the advantages of dry processing for minerals.INTRODUCTIONThe lack of access to fresh water is becoming a major factor affecting the feasibility of mining projects around the world. According to Hubert Fleming, former global director for Hatch Water, “Of all the mining projects in the world that have either been stopped or slowed down over the past year, it has been, in almost 100% of the cases, a result of water, either directly or indirectly” (Blin et al., 2013). Dry mineral processing methods offer a solution to this looming problem."

Jan 1, 2016

By Mario A. Morin

Mine design, planning and scheduling is a very complex, iterative process comprising several interrelated and interdependent activities. Understanding how this process works, identifying the critical pieces of information and the decisions to be made is key to initiating business process improvements (BPI) or business process reengineering (BPR) activities. Fundamental to most BPI and BPR work is some form of systems analysis. Structured Analysis is a powerful systems analysis technique that is well suited for modeling and analyzing complex process activities. Through a series of diagrams, this paper presents a vertical slice through the analysis work performed for formally describing the underground hardrock mine design and planning process. These diagrams illustrate how simple graphic constructs can be used to decompose the most complex situations into easily understandable diagrams that facilitate understanding, communication, improvement and reengineering.

May 1, 2002

By George Kellock

Introductory The Alberta Provincial Government has contemplated a revision of the Mines Act for some time past, and it is understood that a definite decision has now been made to do this at the next session of the Legislature. The Operators&apos; and Miners&apos; organizations of the Province have been asked, or at least have been given the opportunity, to submit their views and ideas relative to the proposed changes. The operators have already drafted out a number of changes which they feel would improve the Act from the standpoint of safety and practicability, and this paper has been prepared so that the general membership of the Rocky Mountain Branch of the Institute, which is composed largely of the operating and certificated officials of the mines, might have an opportunity to discuss, criticize, and improve upon the suggested changes which the operators are putting forward.

Jan 1, 1929

By A. J. Petrina

"At Craigmont Mines Limited, Merritt, B.C., tests were begun in March, 1965 to evaluate the use of shotcrete as a method of ground support m development headings; previously, ail drifts had. required support, which was accomplished mainly by timber and occasionally by the use of rockbolts. The tests demonstrated conclusively the effectiveness of shotcrete for supporting Craigmont's ground. Gradually, the use of timber for ground support was virtually eliminated in favour of shotcrete. This paper describes the equipment used, the operation of the equipment, pertinent cast data and opera ting details. Also discussed are other uses developed for the shot-creting equipment, the use of reinforcing bar rockbolts, and a method used at Craigmont for lining long vertical ore passes with steel plate and concrete as part of the raising cycle."

Jan 1, 1968

By M. Cai

"It is well known that Peak Particle Velocity (PPV) plays a critical role in triggering rockburst damage in burst-prone underground mines. To estimate the PPV distribution around excavations, advanced numerical modeling can be used. In wave propagation numerical modeling, velocity field is often assumed to be uniform around an excavation. However, it is observed that wave velocities near mine openings are not constant, but rather non-uniform. Wave velocity in a rock mass depends on many factors such as rock quality and confinement. In particular, confinement has a large influence on wave velocity. The confinement around an excavation is low at the wall boundary and increases gradually and reaches a constant value far away from the excavation boundary. Hence, stress redistribution due to excavation will have a profound influence on wave propagation in underground mines. A better understanding of the influence of excavation effect on wave propagation helps to interpret the field observation of rockburst damage and improve mine safety. For this purpose, a non-uniform velocity model need to be constructed and the influence excavation effect should be taken into account in numerical wave propagation modeling.In the present study, a non-linear velocity model is developed firstly by considering the influence of confinement on wave velocity. This model links wave velocity to confinement explicitly. A coupled numerical method is then developed and used to study the seismic wave pattern around excavations in underground mines. Two codes, FLAC and SPECFEM2D, are coupled in the analysis. The motivation of developing the FLAC/SPECFEM2D coupled approach is to take merit of each code, such as the stress analysis capability in FLAC and the powerful wave propagation analysis capability in SPECFEM2D. The coupling process is realized through three steps: (1) static stress redistribution around an excavation is analyzed in FLAC; (2) data for coupling analysis, such as non-uniform velocity field (based on the new developed velocity model), mesh, absorbing boundaries, etc., are generated by FISH functions in FLAC and passed to SPECFEM2D; and (3) wave propagation modeling is performed in the SPECFEM2D considering a fault-slip seismic source. Because stress redistribution around the excavation is considered, non-uniform velocity field for the SPECFEM2D model can be obtained and this is a notable feature of this study. Very large difference in the S-wave response in these two modeling approaches with uniform and non-uniform velocity fields can be seen from the modeling results.Using the FLAC/SPECFEM2D coupled modeling approach, accurate velocity models can be constructed and this in turn will help to produce accurate PPV distribution around the excavations. Accurate PPV contours can be used to identify high rockburst risk zones for improved dynamic ground support strategy."

Jan 1, 2015

By David R. Ray, Arthur J. Pyron, William F. Thomann

"Proterozoic plutonic and volcanic rocks in the Franklin Mountains, west Texas, exhibit similar values in average concentrations of equivalent uranium (eU), equivalent thorium (eTh) and equivalent potassium (eK) when compared to Proterozoic igneous rocks of the southwestern United States. Variations of radioelement concentrations for all Proterozoic igneous rocks of the Franklin Mountains range from 1.1 to 357.1 ppm U, 2.1to 259.1 ppm Th and 2.5 to 10.2% K.Recent geologic mapping of the Proterozoic rocks in the Franklin Mountains revealed several types of granites previously unrecognized, and these warrant further exploration for U and Th resources. Fluorite-bearing granites and riebeckite pegmatites are likely targets for further investigation, as these have the highest U and Th concentrations compared to all other granites.IntroductionThis is a summary of the paper presented at the CIM Geology Division Uranium Symposium held in Saskatoon, Saskatchewan, September 8-13, 1981. The purpose of this study was to evaluate the distribution of uranium (U), thorium (Th) and potassium (K) in Proterozoic igneous rocks in the Franklin Mountains, and compare radioelement concentrations to Proterozoic igneous rocks elsewhere in the southwestern United States.General GeologyThe Franklin Mountains are located in west Texas and southcentral New Mexico, within the southeastern part of the Basin and Range Province o f the southwestern United States. The Franklins are a complex fault-block range trending northsouth with strata dipping toward the west. Ages of the rocks range from Proterozoic to Cretaceous. Harbour (1972, 1960) provides the most recent account of the general geology of the Franklin Mountains. Most recent accounts of the detailed Pro Proterozoic geology o f the Franklins are provided by Hoffer (1976), Thomann (1980, 1981), Pyron (1980), Ray (1982) and McCutcheon (1982)."

Jan 1, 1983

By L. P. Srivastava

Rock bolts have been used since long to enhance the shear strength response of jointed rocks in civil and mining engineering structures. However, the assessment of strength response of a rock mass reinforced with rock bolts remains an unresolved problem till date. In the present article, an attempt has been made to study, through physical model tests, the shear strength enhancement of a blocky mass due to provision of passive rock bolts. Direct shear tests were conducted on large specimens of size 750 mm x 750 mm x 900 mm of rock mass under a normal stress varying from 0 to 2.0 MPa. Concrete was used as a model material to simulate intact rock and, elemental blocks of size 150 mm x 150 mm x 150 mm were used to form the mass specimens. Steel bolts of 6 mm diameter with 2 mm thick grout were used to reinforce the mass. Three different configurations of bolts were adopted. Observations were made on shear stress, horizontal shear displacement, and dilation during the tests. Effect of normal stress and reinforcement on peak shear stress and shear stiffness was studied. It is observed that the rock bolts enhance the shear strength of the mass by preventing sliding along the shearing plane, and by inducing additional normal stress due to tension mobilized in the bolts. The rock mass, therefore, becomes stronger due to the high degree of interlocking produced by the bolts. Shear strength of the mass increases with increasing numbers of bolts. In the case of reinforced mass, the enhancement in shear strength due to provision of bolts decreases with an increase in normal stress. The provision of bolts improves the cohesion of joints substantially. The effect on friction angle is low. The shear strength enhancement depends on the area of the bolts, spacing of the joints, spacing between the bolts and the cohesion of the intact material. A correlation has been established using which the enhancement in shear strength due to the provision of bolts can be assessed.

Jan 1, 2015

By Wallace R. Horn

"MR. CHAIRMAN AND GENTLEMEN :I begin this talk by making a couple of comments which are of the nature of disclaimers.Firstly, and as the Chairman has otherwise indicated, I was neither ""born into"" nor have I spent more than a few years of my professional life in the mining industry. I mention this because many might, and perhaps rightly, consider that an added qualification in presenting a report of what the industry has accomplished. Indeed, I am not here to blindly defend all of its actions and inactions in respect to environmental control over the years. Nor am I here to seek absolution of the industry's past transgressions - if indeed that is the word. Mistakes might be a better one. I concluded some time ago that the effects of those mistakes are too difficult to assess against the sea of errors of our total society. I should mention too that I am not an environmental engineer or specialist - only a portion of my interest is involved with this field. Perhaps this permits a perspective which allows a more accurate and objective view.One further comment here. My job today, as I understand it, is to generally report upon the nature and extent of the response of the metals mining industry to control of the environment. In the case of an industry operating at more than a hundred locations and for various reasons at various stages of progress, it is not an easy job. On the other hand, I wanted to avoid the use of generalities because, especially within the context of environmental or ecological opinion and of the practice of condemnation of industrial segments, I think we've had about enough of generalities until we know far more than we do.Finally, I am quite aware that a statement of future plans to achieve environmental control does not impress or satisfy as many people as it may have done some years ago. Public opinion demands to know what is currently underway, today."

Jan 1, 1972

By R. M. Young

In. East Kootenay, two Companies are operating, the Crow&apos;s Nest Pass Coal Company of Fernie, with mines at Coal Creek and Michel, and the Corbin Coal and Coke Company, of Corbin and Spokane. Wash., with mines at Corbin. The Crow&apos;s Nest Pass Coal Company has also coke-ovens of the bee-hive type at Fernie and Michel. The mines have a productive capacity, with present development and plant, of approximately 1,500,000 tons of coal, and of 300,000 tons of coke annually. The total production in 1923 was 828, 990 tons of coal and 65.990 tons of coke. In the early years of operation, the mines furnished a very large percentage of their output to the railways and smelters. These were, in fact, the primary markets for which the mines were opened and the ovens constructed. The Great Northern Railway had built into Femie, and later extending its line to Michel, became a heavy consumer of both of these mines. The Spokane International, connecting the Crow&apos;s Nest branch of the C.P .R. with Spokane, furnished tonnage to Corbin. The Canadian Pacific Railway bought for Crow&apos;s Nest consumption. The smelters at Grand Forks and Trail in the Boundary country were large and steady consumers of coke, while in-termittently Northport, Butte, Helena, and Great Falls shared in the product of the ovens.

Jan 1, 1924

By S. Shairp

At the Hudbay zinc pressure leach plant, filtration and washing of the second stage leach slurry takes place on a vacuum belt filter prior to disposal to tailings. Due to periods of poor filterability, laboratory studies were undertaken to investigate the effect of temperature of the filter feed slurry, and to compare filterability to the resulting cake particle size distribution.

Jan 1, 2014

By Elbasher M. E. Ahmed, Indresan Govender

"A mechanistic model of axial charge segregation in rotating drums is presented. We show that granular material composed of different frictional properties diffuse into axial bands as a consequence of concentration fluctuations in the free surface layer that is caused by friction-limited mobility. A Bagnoldian stress assumption ensures an asymmetric free surface profile thereby providing the essential ingredients for the evolution of axial bands and the subsequent band coarsening observed in the literature. The formulation is sensitive to the boundary conditions of tumbling mills, including particle size and density, mill speed, inter-particle bulk friction, end wall friction and drum geometry (length and diameter).INTRODUCTIONA mechanism to fully describe the axial segregation of charge in a rotating drum remains elusive to the mineral processing industry. With regard to low aspect ratio mills (like ball mills), current thinking favours the use of closed circuit mills with correspondingly low residence times to offset the completely random contact probabilities between particles and balls (Wills & Napier-Munn, 2006). Conical end caps are argued to exploit the centrifugal force to achieve a regular gradation of ball size along the mill with larger sizes at the feed end and smaller ones closer to the discharge. However; segregation along the length has been observed in the absence of conical end caps (Oyama, 1939; Levine, 1999): In these investigations, sufficient differences in the particle’s mechanical properties (particle size, density, shape, surface roughness) was enough to successfully achieve axial segregation. Figure 1 shows the segregation of a bimodal distribution (by size) into bands of larger (darker colour) and smaller (lighter colour) particles."

Jan 1, 2016

By A. F. Buckham

Introduction Several basins of the Nanaimo series, a group of coal-bearing sedimentary rocks of Upper Cretaceous age, underlie parts of Vancouver island and the adjacent gulf islands. One, the Nanaimo basin, occurs on the southern half of the west shore of the gulf of Georgia. About fifty square miles at the north end of this basin are known to be underlain by productive coal seams, this area being known as the Nanaimo coal field. Coal has been mined from two horizons- that of the Wellington seam, fairly low in the series, and that of the Newcastle and Douglas seams, about the middle of the series. Coal has been mined here since the fall of 1852. About fifty million tons have been produced, almost half the total production of British Columbia. About seventy-two years ago, James Richardson of the Geological Survey made a reconnaissance of the coal measures on Vancouver island, and thirty-five years ago C. H. Clapp mapped and reported on most of the Nanaimo coal field. Twenty-four years ago, J. D. MacKenzie extended the work to those areas not mapped by Clapp. MacKenzie died before the results of his work could be published, but did issue a revised estimate of the Goal Resources of Southern Vancouver Island. Work by the present writer is a further contribution by the Geological Survey to knowledge of the island coal measures. Having spent more time in the field, and having had more data at his disposal than were available to his predecessors, the writer has been able to throw additional light on the Nanaimo, and other, coal fields on Vancouver island. He is indebted to Canadian Collieries (Dunsmuir), Limited, and to its officials for access to much valuable information in their possession.

Jan 1, 1947

By M. Narita, S. Nakayama, M. Fujihara

Hibi Kyodo Smelting Co., Ltd. was founded in 1968 and celebrated its 50th anniversary in 2018. In 1972, we started producing copper cathode with a production capacity of 84 KTPY. Since the company founding, we have undertaken seven expansion projects, and our current copper-cathode production capacity is 290 KTPY. To increase our production efficiency, two tank houses were converted from Conventional process to ISA process in 2006 and 2014. In another investment, we equipped a continuous glue dosing system, which allowed for strict additive-concentration control, yielded quality improvements and reduced the power-consumption rate. Along with an increase in the production of copper cathode, the amount of impurities eluted from the anode increases. To solve this problem, the chelate-resin purification process that was introduced in 1983 was renovated, and impurities could be recovered more efficiently. In this paper, we report various improvements that have been implemented at the refinery since 2000. INTRODUCTION Tamano Smelter and Refinery of Hibi Kyodo Smelting Co., Ltd., founded in 1968, celebrated the 50th anniversary of its founding in 2018. The Tamano Smelter opened its No. 1 tankhouse in 1972, and began operating No. 2 tankhouse in 1984. Thereafter, with continuous production increases and technical improvements, electrolytic copper production was increased from 84 KTPY to 290 KTPY as shown in Figure 1. Table 1 shows the major operating facilities and operation data in 2017.In this paper, details of equipment introduced to continuously dissolve and add glue, various improvements made to the chelate resin process, enhancements made to the crude Ni sulfate process, and another vibrating screen introduced to the copper slime processing flow in accordance with the expansion of copper production capacity since 2000 are reported.

Jan 1, 2019

By R. G. S. Mussi

An inclined cooling plate is utilized as a modification in the compocasting process of magnesium alloy and the mechanical properties of the composites obtained are studied in this work. Based on crystal separation theory, molten AZ91D is poured onto an inclined plate in order to produce solidification nuclei inside the fluid metal, and is mechanically stirred while reinforcement is added. Particulate SiC was utilized as reinforcement in quantities varying from 0 to 15%vol. Dispersion of the reinforcement was observed by macro and microstructure analysis. SiC was properly mixed into matrix until 15%vol., and Vickers hardness tests were carried out for the composites produced. Results obtained for hardness were shown to increase with reinforcement addition and comparable to those of traditional compocasting. Utilization of Inclined Cooling Plate produced good inclusion and homogenization of SiC through an AZ91D matrix, at lower temperatures and shorter times than traditional compocasting.

Jan 1, 2006