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By A. B. Isaeva, A. Yu. Lein, A. A. Karpenko, V. V. Serova, A. P. Lisitzin, V. Yu. Rusakov, V. N. Lukashin

Abstract - The flux of sediment matter was determined using sediment traps near a black smoker ("Saracen’s Head," Broken Spur hydrothermal field) and the mineral and chemical compositions of the settled matter were examined. The metallic minerals are represented by Fe sulfides (pyrite and pyrrhotite), and Cu and Zn sulfides are also found in small and equal quantities. The hydrothermal suspended matter contains abiogenic calcite in amounts comparable to that in Ca sulfates. The content of silica and, specifically, of amorphous Si is unusually low. Such correlations between chemical elements and minerals, together with the isotopic compositions of S and C, are characteristic of a relatively young and active stage in the evolution of a hydrothermal system. Sediment traps within and under neutrally buoyant hydrothermal plumes collected biogenic material in addition to hydrothermal components. Microbial chemosynthetic production of organic carbon near the hydrothermal vent is comparable to primary production in the euphotic layer. Fe, Zn, Ca, Si, Ba and P are enriched in particulate matter in comparison to the background. A vast compound plume containing the discharge of multiple hydrothermal vents was found to the south of the Broken Spur hydrothermal field.

Jan 1, 1999

By Tedd E. Lister, Andre Anderko, Peiming Wang

Mobile electronic devices such as smart phones and tablets are a significant source of valuable metals that should be recycled. Value metals in phones are gold, palladium, silver, copper, cobalt and nickel. Devices now contain increasing amounts of rare earth elements (REE). Effective recycling schemes should include the recovery of these critical materials. Targeted recycling of items containing more of the less available critical materials could address their future criticality. This presentation will describe an electro-hydrometallurgy approach to efficient recycling of metals from scrap mobile electronics. The electrorecycling (ER) process generates oxidizing agents at an anode while reducing dissolved metals at the cathode. Development of the process involved generation of E vs pH diagrams, complemented with metals dissolution experiments used to assess the effectiveness of various solution chemistries. Although several schemes were envisioned, a two stage process has been the focus of work: 1) initial dissolution of Cu, Sn, Ag and magnet materials using Fe+3 generated in acidic sulfate and 2) final dissolution of Pd and Au using Cl2 generated in an HCl solution. Results from laboratory work will be discussed.

Jan 1, 2014

By Alan B. Morrow, William A. Poe

"Minerals processing operations are constantly challenged with improving production rates, yields, energy efficiency and process stability. Advanced Process Control has proven to be an effective tool for improving operations by capturing the full process capabilities consistently. However, the velocity of applying the technology as well as the sustainment of these significant benefits has been hampered by the usability of the software and adaptability of the applications.Some of the new technology developments that improve the usability and adaptability of advanced process control include:• modern and intuitive user interfaces,• customizable models to support unique process behavior,• fast and flexible OPC connection tools,• automated model building,• integration with first principles dynamic models and• improved performance monitoring.This paper will briefly discuss the new technology developments that have improved the usability and adaptability of advanced process control and how this can affect minerals processing operations.In today’s environment, Minerals Processing plant managers continuously face new challenges and requirements including:• higher energy efficiency,• increased run lengths,• reduced product quality variability,• reduced emissions,• higher availability, and• lower operating costsOperating a unit to meet these challenges in real time is not easy for operators and conventional process control systems. However, innovatively using existing technologies in Minerals Processing plants can improve operations on a minute by minute basis and reap significant benefits.Advanced Process Control (APC) can extract the maximum performance benefits from existing equipment while respecting plant operating constraints. Expensive capital projects to upgrade equipment are not always necessary. Advanced Process Control can deliver significant economic benefits by maintaining the plant at its most profitable point as conditions change."

Jan 1, 2016

By R. H. Seraphim

"The Phoenix Camp, in the Boundary Creek district of southern British Columbia, produced before 1920 about 15 million tons of ore averaging more than l ·5 per cent copper, about 0.03 ounces per ton in gold, and 0·5 ounces per ton in silver. Attwood Copper Mines Ltd. conducted an exploration program in the Phoenix area from 1951to1953.Publications on the camp are listed in the bibliography. Brock's work was not sufficiently detailed to unravel the structural and stratigraphic pro bl.ems. The work of LeRoy and McNaughton is referred to later.The stratigraphic column is as follows:Tertiary.Midway Formation: Volcanics and hypabyssals; dacitic to basaltic flows, with associated dykes and sills of syenite (pulaskite in part) and augite porphyry.Jura-Cretaceous.Intrusives of quartz diorite and diorite (nearest outcrop two miles from Phoenix).Late Palaeozoic or Triassic (Attwood Series).Brooklyn Formation: Sharps tone conglomerate, limestone, grey-wacke and/ or andesitic tuff, with minor shale and basalt. Rawhide Formation: shale with minor conglomerate.Early Palaeozoic.Knob Hill Formation: Chert and andesite, with minor limestone, shale, and serpentine.This column differs from that of LeRoy in two important respects: (I) Attwood's work indicates that the Rawhide shale is basal to, rather than stratigraphically above, the Brooklyn formation. The shale contains conglomerate lenses, which become more abundant and thicker toward the top, and grades upward into Brooklyn conglomerate. Ripple marks indicate that the shale is right side up."

Jan 1, 1949

By G. W. Poling, J. R. Hoffert

"A common practice in preventing gravity-fed tailing pipeline from plugging due to sanding is to add lime at relatively high dosage rates. The lime affects the rheology of the slurry ""vehicle"" which transports the coarser particles in a heterogeneous flow-regime. This paper describes a study of the effect of lime on the critical deposition velocities and friction head losses of Highmont Mining Company's mill tailing. Testwork using an extrusion viscometer was related to the surface chemistry changes brought about by the high lime additions. Lime additions which typically increased the tailing pH from 8.4 to 11.5 reduced the critical deposition velocities from approximately 3.2 to 1.7 m/sec.IntroductionCommon practice, at least in base metal concentrators in British Columbia, is to use high lime additions in tailing slurries when the pipeline becomes partially plugged with sands. Some concentrators, such as the Highmont Mining Co. Ltd. plant, add lime on a continuous basis during low tonnage periods and during startup/shutdown transition s. Although such high lime additions often solve temporary plugging problems, the effect of lime on slurry rheology has not been well understood.Slurry pipelines are designed to transport solids in suspension with a minimum of wear and without particle deposition. These two objectives are in opposition because the velocities required to maintain solid suspension can sometimes cause high head losses in the pipeline, as well as wear problems. Thus, the optimum velocity for a long distance slurry pipeline is in the range that provides just enough turbulence to keep coarse particles in suspension."

Jan 1, 1985

By F. S. Hoseinian, M. Irannajad, M. Safari

In this study, the effect of chemical interactions of materials used in ion flotation on the removal of Ni(II) ions from low concentration synthetic wastewater was studied. Sodium dodecyl sulfate (SDS) and ethylhexadecyldimethylammonium bromide (EHDABr) as collectors and methyl isobutyl carbonyl (MIBC) and Dowfroth250 as frothers were used. To investigate the effective parameters and interactions of them, 16 experiments including 6 level variables were performed by supporting DX7 software and on the bases of 2-level factorial method. In the first step, the tests were conducted in a Hallimond tube. The result showed that collector of SDS and frother of Dowfroth 250 had appropriate interaction with each other at pH = 3. In the second step, optimal results from the first step were evaluated in a mechanical flotation cell. The removal of Ni(II) ions increased by increasing the time of flotation and they have a direct relation with the water removal. The kinetics study shows that the order and the rate of removal of the reaction do not follow any of the zero-order, first-order and second-order equations. The flotation rate curve on the removal of Ni(II) ions will divide the separation process to two stages, a fast flotation rate at the first stage and a slow flotation rate at the second stage. Ni(II) ions removal was obtained 88% at the best condition.This study showed that the use of ion flotation was a very effective method for Ni(II) ion removal from industrial wastewaters.

Jan 1, 2016

By Y. Vermeulen, J. Simoes, P. Guillo, A. Di Donate

New design techniques have been developed to optimize continuous casting (CC) refractory components. The overall objective is to increase CC productivity as well as steel quality by using optimized refractory from tundish-to-mold. These techniques allow the prediction of steel and refractory chemical interactions and, thus, steel chemistry evolution as well as build up and corrosion occurrence. Specific fluido-dynamic models (CFD) have also been developed to better take into account the physical parameters at the steel/refractory interface and to optimize steel flow control. The CFD model can be coupled with refractory chemical interactions to simulate steel chemical evolution. These two different approaches result in shape and material modifications. They are completed by dedicated thermal stress analysis in order to improve thermal shock resistance. The mechanical FEA evaluations take into account specific mechanical behavior of refractory components as well as high temperature evolution of their properties.

Jan 1, 2004

By Percy Coulter

"GeneralThe Malartic Gold Fields mill is presently treating ore from four different companies. The ore is delivered by truck, by the shipper, and dumped into the Malartic Gold Fields ore bin. This ore varies in size from 'Run of mine' to minus 8 11, All ore is crushed to pass a 3/ 8 11 x 4 11 cross slotted screen.Weighing and SamplingAfter crushing the ore passes over an adequate-weigher (250 T .P.H. capacity) on its way to the fine ore bins. This weigher has a remote counter at the sampling point.A 36” Vezin sampler cuts 15% from the ore stream as it enters the mill bins. This portion is elevated, by means of a short belt conveyor, to feed the No. 2 Vezin sampler. (This elevation is necessary to give headroom for the following machines). The ore on the conveyor is levelled to give a uniform stream to the second sample cutter. The second, third and fourth cutters are 2411 •The No. 2 Vezin sampler cuts 19% from its feed and this portion falls directly into a 1611 x 1011 Denver rolls crusher. This crusher reduces the ore to -1/ 8 11 , approximately. The discharge from the rolls crusher falls on a revolving circular plate with scraper, which gives a uniform stream to the No. 3 Vezin sampler.The No. 3 Vezin cuts 10% from its feed. This portion falls on another revolving plate to give a uniform stream to feed No. 4 Vezin."

Jan 1, 1966

By S. Akhlaghi

In many electronic/optoelectronic devices, interaction between the metal stack and solder is undesirable. If a reaction happens, a nonuniform joint containing spikes and voids is likely to form and as a result the heat dissipation deteriorates significantly, which in turn, leads to the degradation of the bond. In the present work the interaction between Ti/Mo/ Au metallization system, which was sputter deposited on AlN substrates, and Pb-Sn solder was studied by using scanning electron microscopy (SEM). Also, an EDX system was used to trace the changes in chemical composition of the layers after solder tests. The microstructural examinations show that the Ti and Mo layer from the Ti/Mo/ Au metallization system are not impermeable enough and thus Ca from the surface of the substrate moves all the way up to the interface of Au/Mo and forms an intermetallic at the interface, which grows over time.

Jan 1, 2006

By M. E. Stutt, R. H. Rehder

"The mining industry is taking advantage of the increased performance resulting from the use of variable speed A C drives for large motors. This technology provides increased efficiency under the variable speed and torque requirements of such drives as mine hoists, conveyors, and air moving equipment. The technology does introduce voltage spikes on the voltage wave form that stress the insulation system to a greater degree than would occur with a constant voltage source. These voltage spikes must be considered in the design of the insulation system used for these motors.BackgroundHistorically the insulation systems for large AC motors were designed to withstand with reasonable life the voltage stresses of a 60 Hz constant sinusoidal voltage. One of the design tests is a voltage endurance test that requires the application of a 60 Hz voltage from conductor to ground equal to four to five times normal and establishing a time to failure. These higher than normal voltages accelerate the normal aging process by causing extensive partial discharge activity (corona) within the insulation system and the time to failure is a relative indication of insulation life.In addition to the voltage endurance test at 60 Hz, the individual coils are subjected to a surge voltage test to establish the withstand capability of the turn to turn insulation under switching surge conditions. The surge voltage is a fast rise time, 0.2 microsecond to crest value, voltage spike that can be caused by a circuit breaker or contactor closing operation. These voltage spikes can have a crest value of greater than 3.5 times the normal line to ground crest voltage of the normal 60 Hz power supply. The standard withstand test value is thus 3.5 times normal line to ground voltage. Because the voltage surges or spikes occur mainly during start and stop switching conditions, voltage endurance under these conditions has not been a major factor in insulation system design."

Jan 1, 1995

By CIM Standing Committee

The CIM Definition Standards on Mineral Resources and Reserves (CIM Definition Standards) establish definitions and guidance on the definitions for Mineral Resources, Mineral Reserves, and mining studies used in Canada. The Mineral Resource, Mineral Reserve, and mining study definitions are incorporated, by reference, into National Instrument 43-101 – Standards of Disclosure for Mineral Projects (NI 43-101). The CIM Definition Standards can be viewed at mrmr.cim.org. Readers should be aware that reports written by persons issuing technical reports that disclose information about exploration or other mining properties to the public in Canada are governed by a number of securities regulations.

May 10, 2014

By E. A. Haack, L. A. Warren

Microbial biofilms are essentially biologically driven, geochemically reactive interfaces between solid surfaces and aqueous solution. Field investigation of acid rock drainage (ARD) associated biofilms at the Onaping nickel mine (Onaping, ON, Falconbridge Ltd.) characterizing: (1) micro-geochemical gradients (pH and 02) (2) metal fractionation amongst biofilm solid components, and (3) microbial communities; over both seasonal and diel timescales, indicates biofilms are highly metal reactive. Results show that biofilms accumulate metals seasonally within two microbially controlled solid fractions: amorphous hydrous manganese oxide (HMO) biominerals and the organic biofilm matrix. The biofilm geochemical microenvironment, driven largely by microbial activity, dynamically impacts biofilm metal behaviour over diel timescales. These results indicate that microbes can play significant roles in bulk system reactive metal transport. On-going investigation seeks to characterize the microbial players and the microbial-geochemical linkages involved in Mn oxyhydroxide formation and subsequent metal sequestration, with the goal of engineering this microbial activity as a bioremediative approach. This approach will have utility beyond specific application to the Falconbridge Onaping site to ARD mine environments in general, as the likely microbes involved in these processes are typically common across ARD systems.

Jan 1, 2004

By G. Binks

In 1997, the Zinifex Hobart Smelter ceased ocean disposal of jarosite and the flowsheet was converted to reject iron as paragoethite. This paper describes the evolution of the flowsheet since the changeover and considers future flowsheet developments. The major change to the flowsheet has been an increase in the silica content of the calcine resulting from treating increasing levels of Century concentrate. The high silica levels impacted on the paragoethite precipitation stage, causing a deterioration in the settling and filtration characteristics of the paragoethite and an increase in the contained zinc level. The implementation of a two stage neutral leach step has enabled the flowsheet to cope with the higher input silica levels. Future developments include an understanding of the form of the zinc in the paragoethite and options to lower the zinc level to improve the overall zinc recovery.

Jan 1, 2006

By Douglas Brand

"The data that many mineral processing plants make use of, is provided by samples taken from sampling systems which are inadequately designed or improperly maintained, and therefore cause detrimental effects to plant operations, production planning and metallurgical accounting! Poorly designed or maintained sampling systems will likely produce low probability samples which give the operator a false sense of security of the product and the process. If data is the basis for action (Flintoff, 1992, p.2), then using the resulting suspect or bad assays by operators, control systems, or metallurgist and administration personnel will act and make decisions which may adversely affect the profitability of a processing plant. Here we will discuss some of the fundamental sampling problems, propagation of errors and a method to estimate what impact this has on an operations Net Smelter Return.INTRODUCTIONIn order to control a mineral processing plant at its best potential, it is necessary to obtain the best possible measurement results of the metal or mineral in question. The sample which is delivered to a measuring instrument, or lab, needs to be of the highest probability to be able to achieve this. This paper will discuss the effects of sampling errors on grade / recovery and grade / Net Smelter Return (NSR) and provide a method to estimate the monetary advantages of using probabilistic sampling in a processing plant.REVIEW OF SAMPLINGSampling, by definition, is the removal of a small representative portion from a total consignment, or flow, for the purpose of accounting or process control.• A sample can only be considered representative, if each and every increment collected, in each of the sampling stages, is representative.• Each particle of the sampling lot must have the same probability of being included in the final sample.• If both of the above conditions are met, then the final sample will be representative of the complete sampling lot.It is commonly known that in order to take truly representative and probabilistic sample, best practices indicate that:• The total stream should be sampled.• The sample cutter should intersect the sample at right angles to the flow.• The sample cutter should travel through the stream at a linear and constant speed and the speed deviations should be less than 5%."

Jan 1, 2016

By H. Ishimoto

It always has been a serious issue to improve safety in mine sites, demolition work sites, and civil engineering work sites. Especially, collision accidents caused by construction equipment damage not only the productivity of operations but also the health and life of workers in those work sites. To solve this problem, a variety of worker auto-detection means are developed so far, but they have not still become widely used in actual worksites. There have been two controversial points in the prior methods. One is that they were not enough in respect of the detection accuracy and certainty, and the other one is that the information of the detection results was not comprehensible to the operator of equipment. In this paper, the functional requirements of the obstacle detection system in earth moving work site is redefined at first, and then, it is proposed to apply a stereo vision to the obstacle detection system for an excavator. The system consists of horizontally arrayed two digital cameras with low distortion lens, an image processing controller, and a monitor for an operator in the cab. Stereo vision calculates the depth image from images of two cameras and detects the presence of obstacles, its distance, direction, and dimensions. Sensed obstacles are informed to the operator in the monitor image. Preliminary experiments are conducted with a stereo vision system mounted on a real equipment in a demonstration site. The result shows that two controversial points of the conventional technologies are improved, and that the applicability of this system is validated.

Aug 1, 2013

By Kenneth Blower

This paper gives a detailed coverage of the ore flow through the primary crusher, cobbing plant and concentrator, including equipment sizes, recoveries, reagent consumptions and product descriptions. Special features, such as rubber chutes, rubber-lined mills, pebble-mill grinding, steam-hooded filters and process control instrumentation, are also discussed.

Jan 1, 1968

"Since all gold mills must sooner or later be cleaned up for permanent shutdown it was felt that a record of what was done at one mill might be of some help to those who will have to do the same job in the future,In cleaning up the mill of Delnite Mines Limited, I had an advantage that most mill superintendents will not have in that I started up the mill and was there until it was shut down, It was also known for two years approximately when the shutdown would be and for a year almost the exact time. This, of course, made careful planning possible and enabled me to get advance information that wouldn't have been available had the shutdown come unexpectedly,Early in 1964 calculation of ore reserves and the known number of working places available indicated that the mine would run out of ore sometime in August or September but not later than October, The time of course would vary with the number of competent miners that could be retained until the shutdown. Since the mining method used exclusively on the ore then remaining was cut and fill, it was known that once mining operations ceased it would require at most two days to crush and grind the last of the ore.In March 1 964 I took samples of the concrete floor under the precipitation presses, in the flux room and furnace room of the refinery and from the assays obtained proved that there would be no profit in breaking up the concrete to recover the gold from it, Samples taken from the top half inch of the concrete floors assayed less than 0, 10 oz per ton,"

Jan 1, 1966

By C. A. Y. Shephard, H. L. Brusset

Pressure maintenance by water flooding in the Pembina Field made consideration of wet crude dehydration and disposal of the produced water mandatory. Crude dehydration, the treatment and disposal of produced water, as well as the sale of gas and crude oil were expected to be handled more efficiently at one central point than at several conventional batteries. This plan was effected by routing the produced fluids to the central station by way of several well testing batteries referred to as satellites. To realize the full efficiency inherent in such consolidation the entire system was made self-regulating. Programming ensures the testing and proper routing of all products to their destination. Forty producing wells have been self-operated during the winter 1959 -1960 with gratifying results.

Jan 1, 1960

By D. Chakravarty, B. Samanta, D. Ghosh

Autonomous robots are useful for 3D underground mine mapping to avoid human exposure to hazardous spaces. To prepare a precise mine map, a self-navigating robot must navigate an arduous path, avoiding obstacles and sensing the environment. A prototype laboratory-scale robot was built and evaluated through a mock-up in a test mine gallery. It was outfitted with a 2D laser scanner, a stereo camera for obstacle avoidance, and a high-precision, laser-based imaging and digitizing system for collecting 3D point cloud data. Various algorithms were used for scan matching to facilitate simultaneous localization of the robot for mapping.

Jan 1, 2014

By A. G. Roach

MILLING of Nova Scotia gold ores began in 1862 with arrastras and wooden stamps and has progressed to heavier stamps followed by tables and other forms of concentration for the recovery of the sulphides. Chlorination and cyanide leaching of the concentrates has been practised, and in 1936 the combined amalgamation and all-sliming cyanidation plant of Seal Harbor Gold Mines was built. It has since been found that it is not necessary to cyanide the full tonnage and now only the concentrates are being so treated. From his experience in this enterprise, the writer presents the accompanying flow-sheet and supporting comments. While he has not the temerity to maintain that it is the best or only flow-sheet for Nova Scotia gold ores, he feels that it warrants thoughtful consideration by members of the milling fraternity of the Province. THE ORE The gold in Nova Scotia ores occurs both free and intimately associated with sulphides-chiefly arsenopyrite. Much of the free gold is quite coarse and crystalline. This is especially true when it occurs in white quartz. When in the slate, it is usually in thin plates and scales, frequently coated and discoloured. The values bound up in the sulphides are not amenable to amalgamation and must be recovered by other methods-concentration, followed by smelting or fine grinding and cyanidation. While high freight and treatment charges apply on concentrates shipped from the Province to smelters, a considerable quantity has been so disposed of in the past. However, it is hoped that a customs cyanidation plant will soon become available to producers of these auriferous concentrates in Nova Scotia.

Jan 1, 1938