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By B. Comley, M. C. Harris

There is as yet no accepted method of predicting flotation frother performance in plant processes based on laboratory scale characterisation techniques. This paper investigates the use of dynamic surface tension, using the maximum bubble pressure method, as a means of evaluating frothers and frother mixtures. An adsorption model is presented, which has been used to quantify the role of frother type and concentration during frother bubble interaction, based on the correlation of model parameters to physical frother characteristics. This approach was found to provide useful insight with respect to blending and selection of flotation frothers to meet specified flotation performance criteria.

Jan 1, 2001

Some form of technical library is a necessity for every metallurgical plant, but its form and scope will vary with the conditions of each case. In its simplest form, it may consist of one or two mining journals and a few text books distributed amongst the staff. Again, it may be a separate establishment controlled by a clerk, the technical staff necessarily making its own research into the literature available. A still more elaborate organisation may be established both to supply information when requested and to keep the operating staff in touch with current matters of interest, and the library service of the Electrolytic Zinc Co. of Australasia is of this character.The necessity for such a service is due to several facts. The Company's interests are scattered over three States. Most of its staff members are remote from: good public library facilities and they have few opportunities for exchanging ideas verbally with other metallurgists and engineers. Then, too, the process of recovering zinc by electrolysis, is a young art of which the physical and chemical bases were far from fully known at the time the: Risdon plant was established. Most of the zinc produced is sold abroad, and this unsheltered industry can afford to miss no technical or economic development which may promote its efficiency. Add to these facts the geographical isolation of the Commonwealth and the case for an adequate library is complete.

Jan 1, 1934

By J. R. Stone, G. D. Storm

Design features and operating methods of ASARCO's new unit for the continuous melting and casting of tough pitch copper at Perth Amboy are described. Preliminary studies made for determinitzg economic feasibility and design details are also presented. Cathodes are preheated with oil and melted in an electric furnace at 40-ton per hr rate, from whence the molten copper is fed simultaneously to the wire bar casting wheel and the continuous casting of cakes and billets. In the early 1950's the copper refining furnaces at ASARCO's Perth Amboy plant reached a point where major expenditures would have to be made for replacement of the furnaces and the auxiliary equipment. The problem was whether to continue with the standard reverberatory furnaces or to consider continuous melting in electric furnaces. Reverberatory furnaces have been used for years in the copper industry and for some 50 years at the Perth Amboy plant. Reverberatory melting practice, however, imposes certain restrictions. First, labor costs are high, usually requiring three shifts per day. Secondly, they operate on a batch basis, the conventional operation being a 24-hr cycle including

Jan 1, 1961

WHEN mining and treatment first started at Broken Hill only oxidised ores were available. These ores were rich in silver and lead-the silver mainly existing as chloride and the lead as carbonate.Treatment processes aimed mainly at the recovery of silver, lead being regarded as a by-product, and its recovery, except in so far as it affected silver recovery, was of minor importance.The first ore mined was carted to Terowie and thence railed to Melbourne, being smelted by the Intercolonial Smelting and Refining Co., of Spotswood.The first parcel (50 tons) returned £7442, or £148 16s. per ton to the Broken Hill Proprietary Company.The second parcel of 1053 tons, smelted at the Day Dream smelter, returned 132,142 oz. of silver, but no record is available as to its lead content.These results obtained from two parcels showed that by smelting the ore a handsome profit could be obtained, and Mr. La Monte was engaged to erect two 30-ton Nevada water jacket blast furnaces on Block 13. These furnaces were placed in charge of Mr. P...

Jan 1, 1928

By Pramod C. Thakur

During the past ten years, the US coal industry has experimented with various ways to extract methane from coal seams. Drilling long horizontal boreholes in solid coal from mine workings and vertical gob degas boreholes are becoming standard techniques for methane recovery from coal seams. Prime motivations for such work have always been safety and productivity in mines, but the commercial value of gas so produced is encouraging utilization. The paper reviews various ways to produce methane from coal seams and discusses some utilization projects extant in the industry.

Jan 1, 1984

By Pengfu Tan

A program ?SlagVis? has been developed to simulate the liquidus temperature, phase compositions and viscosities of ZnO-CaO-SiO2-Al2O3-?FeO? slag, such as Imperial Smelting Furnace (ISF) slag and lead blast furnace slag, combined with F*A*C*T slag database and the mathematical model of slag viscosities based on a modified Urbain formalism. The modeling results have been validated by a number of measurements. The effects of slag compositions on viscosities of ISF slag and lead blast furnace slag have been simulated and discussed.

Jan 1, 2005

By B. Leong, H. Joubert

Keywords: Pyrometallurgy, furnace, auxiliary equipment, copper slag launders Pyromet has designed copper launders for tapping slag. What makes Pyromet?s launder design innovative and safe is that it does not have any cooling water channels underneath the launder runner, whilst achieving effective cooling of the runner. If matte burn-throughs were to occur through the launder runner, the risk of damaging water channels and the risk of explosions are reduced. In addition, since the cooling water channels are not harmed, the launder is easily repairable and reusable. Pyromet makes use of Finite Element Analysis to optimize the launder geometry to ensure that sufficient energy is removed from the centre of the launder. Factors considered during the launder design include the suitability of the geometry to the client?s needs, experience from existing installations, and ease of fabrication. Pyromet goes so far as to develop procedures for fabricators to ensure that fabrication issues do not compromise the functionality of the launder. When launder orders are received by Pyromet, the entire fabrication process and the functioning of the launders during operations are monitored to ensure that the launder designs are continuously improving with every installation.

Jan 1, 2006

By G K. N Subasinghe

Metallurgists operating Knelson Concentrators (KC) often rely on manufacturerÆs recommendations for selecting operating parameters, such as fluidising water flow rate and cycle time. Recent studies have shown that these parameters are not only dependent on the machine parameters but also on the feed characteristics, such as size distribution of the gold and gangue particles and the composition of its constituent minerals. It is known that a particle entering a KC initially traverses a circular path within the bowl. For a particle to maintain a given orbit, the required centripetal force must be supplied by external means. It has been argued that this centripetal force, which is dependent on the mass of the particle, its radial position and the rotational speed of the bowl, is provided by the fluid drag force created by inwardly moving fluidising water and the BagnoldÆs force created by the particle/particle collisions. Depending on the fluidising water flow rate, one of two situations can occur where the porosity of the bed increases or decreases, which influences the amount of material retained within the bowl. The amount of material of a given size and density retained in the bowl is thus dependent on the extent of the centripetal force provided. Based on the above concept, a criterion that can be used to predict the amount of material recovered in the bowl has been derived and validated by experimental data. It may also be construed that this criterion demarcates the transition of the bed from a packed-bed state to a fluidised state. By identifying the transition values for the different constituent mineral particles in the feed, it is possible to estimate the optimal fluidising water flow rate that would maximise gold recovery while minimising gangue recovery. In addition, the kinetics of gangue displacement by incoming heavy mineral particles were also studied using synthetic mineral mixtures. The experimental data suggests that this process follows first order kinetics and that the build-up of heavy mineral reaches a maximum. A model has been proposed to predict the optimal batch cycle time for a KC in terms of the feed characteristics and machine operating parameters.

Jan 1, 2006

By J Siliézar

The Ernest Henry Mine (EHM) is situated 38 km north-east of Cloncurry in the Mount Isa – Cloncurry mineral district of northwest Queensland. The EHM orebody is an iron oxide copper gold deposit with an average grade of one per cent copper, 0.5 g/t gold and 23 per cent magnetite, with current reserves of approximately 88 Mt.The copper concentrator is a single line plant with a nominal throughput rate of 1300 tonnes per hour. An average of 350 000 tonnes of concentrate is produced each year containing around 100 000 tonnes of copper metal and 120 000 troy ounces of gold.In December 2009, Xstrata Copper announced approval of a $589 M investment to extend the life of EHM to at least 2024, through the transformation of open pit mining operations to a major underground mine together with the construction of an associated magnetite extraction plant.The EHM magnetite plant extracts the magnetite from the copper concentrator’s tailings stream. It will produce approximately 1.2 Mt of magnetite concentrate per annum at full capacity for export to Asia, making EHM Queensland’s first iron ore concentrate exporter. Construction of the magnetite extraction plant commenced in July 2010 and was completed in January 2011.This paper gives an overview of the development of the EHM magnetite extraction plant flow sheet from the early mineralogy and laboratory test work through to the plant commissioning and early operation of the base plant. It has a major focus on the commissioning learnings from the plant start-up and includes a review of the operational performance of the plant versus original design and expectations.

Jul 11, 2011

Terramin Australia LimitedÆs Angas Lead and Zinc Mine operates in the unique and picturesque environment of Adelaide Hills, 60 km South East of the Adelaide city centre itself. The mine was granted approval for construction by the South Australian Government in April 2007 and the Process Plant was constructed and commissioned in July 2008. This paper outlines the background to the plant design and the approval process given the close proximity to the local town of Strathalbyn, with a major focus on the commissioning learnings from the Concentrator startup for future reference and a review of the operational performance of the Concentrator throughout the first year of successful production versus design and expectations.

Jan 1, 2009

By R. Haecker, S. Bajic, R. Thorpe, A. Palko, M. Kalstrom

"Historically, mineral processors have used inferential data like plant instrumentation, assays, and grind sizes to monitor the performance of their plants. The ability to monitor the minerals themselves on a daily basis has eluded all but the very largest and richest of operations. The advent of a new generation of compact, robust, and user-friendly SEM-based automated mineralogy systems looks set to accomplish this, aiming to bring daily mineral monitoring of plant performance within the reach of all mills from mid-size upwards. This paper describes the use of this machine at Greens Creek Mine, a 2.5 ktpd Ag-Au-Pb-Zn operation with a complex flotation flowsheet. During the trial, the machine provided turnaround from sample collection to reporting averaging 24-36 h for key daily samples. All equipment was located within the compact mill, and proved highly reliable despite the challenging environment. Turnaround time was fast enough for metallurgists to understand, and, where possible, respond to ore and process changes while they were still happening. The plethora of data generated was filtered to a simple report whereby mill management could quickly absorb key daily mineral-based performance indicators. This paper will describe how the data was used to understand the key drivers behind metallurgical efficiency at Greens Creek, and how metallurgists began using the information to enhance daily mill performance."

Jan 1, 2014

By V. J. Parks, Leonard Obert, A. J. Durelli

The state of stress in the region where core discing initiates has been investigated through the use of three-dimensional photoelastic models and the results of this study have been compared with those of a previous investigation of rock models. This comparison showed that discing initiates at a point of maximum shear stress, but that the magnitude of the shear stress, as determined photoelastically, is much larger than the shear strength of the rock as deter-mined from conventional triaxial testing. Moreover the shear stress required to produce discing is not constant, but depends on the applied stress field. Possible explanations for these effects are included in this article. In both exploration core drilling and overcore drilling to determine the stress in rock, occasional sections of the core obtained are broken into a series of discs.I* This discing phenomenon has been investigated in the laboratory to ascertain the state of stress required to produce it. The objective of the study was to obtain information that would make it possible to approximate the state of stress in subsurface rock from which disced cores are obtained. Referred to as the discing test, this laboratory study was conducted to determine the applied axial and radial loads required to produce discing in cylinders of rock from several sources. The dimensions of these cylinders are given in Fig. 1. Discing was produced by first applying an axial load to the cylinder and then diamond drilling the core along its axis. The radial load was then incrementally increased until discing initiated. The discs fractured or ruptured* on surfaces approximately normal to the axis of the core (planes A, B, C, D, E, Fig. 2). In many instances, the bottommost disc fractured before the drill had advanced past the points F and F', cre- ating a mush room-shaped fracture surface FEF'. Alternatively, it was also found that the same shaped fracture surface could be created by first drilling in an unloaded core to some point, say F and F', and then triaxially loading the core until fracture occurred on the plane FEF'. Jaeger and cook4 produced similar fracture surfaces in specimens subjected only to a radial biaxial load. From these laboratory studies and observations made in the field, it can be inferred that fracture or rupture initiates in the proximity of the lowest point in the kerf area, (at F and F', Fig. 2) and that the fracture or rupture surface progresses inward from this point. The experiments described above, however, do not provide any information as to the state of stress at the point at which fracture or rupture initiates. In the investigation discussed in the following sections, a three-dimensional photoelastic analysis was conducted to determine the stress distribution in the proximity of the kerf area of a triaxially loaded plastic (epoxy) cylinder containing a short section of core.

Jan 1, 1969

A simple and cost effective technique to increase fragmentation and burden velocities without making major modification to the overall blast design is with ALTERNATE VELOCITY LOADING OR BOOSTERING OF ANFO. The technique requires the placement of a cartridge or slug of explosive, having higher density and detonation velocity than ANFO, every few feet in an ANFO column. The greater the difference in density and detonation velocity of the Alternate Velocity Load to ANFO, the more pronounced are the results. Emulsions were selected as the Alternate Velocity test explosives because they detonate closer to ideal conditions than most other commercial explosives.

Jan 1, 1989

Cessation of mining on the Bendigo goldfield makes it evident that, as the older generation fades away, knowledge of the famous Bendigo saddle reefs will be limited in the future by their written records. It is important therefore that the summarised account by D. E. Thomas (1953) in the Geology of Australian Ore Deposits should not be misleading. Fig. 6 in this article is stated to portray a cross section and longitudinal section through a series of gold shoots in the Garden Gully 300 ft. reef. The gold shoot along the capof the saddle reef is represented as extending down the east leg in a series of prongs, with the tips of the prongs about 50 ft. apart. It is the purpose of this note to indicate that this illustration can be suspected to be a diagram of the old stopes instead of a diagram of the distribution of gold in the quartz.The original sketches of Figs. 6 and 7 in Thomas' account were extracted, I believe, from the field note books of H. S. Whitelaw, years after his death in the late twenties. Whitelaw was stationed in the Bendigo office of the Geological Survey of Victoria, carrying out geological surveys of the Bendigo mines. He was there for many years before the Gold Research committee started its investigations in 1916 and he was acutely aware of the problem attached to the distribution of gold in the reefs. He had felt concern that manyauriferous reefs were being mined without adequate study and record and he decided, as he expressed it to me, to pick up what he could as he went along. There can be little doubt that the diagrams of Figs. 6 and 7 are products of this resolve.Opportunities to investigate gold occurrences at Bendigo were limited before 1916 because the field was operated by Manuscript received at The Institute 18th November, 1960.

Jan 1, 1961

By John C. Stankus

To improve mine roof bolt performance, Jennmar Corporation commenced the design and development of a new roof control sys- tem. This new system designated "Insta'l Compression", not only improves safety, but is more cost efficient due to reduced amounts of resin needed per bolt installation. In this paper the research and development of this new system will be outlined. Much of the information presented will be actual test data from various underground operations in Alabama, Kentucky, and Pennsylvania. The development of this system will also cover the design of a new expansion shell, resin compression ring, anti- friction washer, and upgrading of material specifications.

Jan 1, 1990

To date Iron Monarch is the most important Australian source of iron ore and since HH5 has produced about 84 million tons of direct shipping ore containing 62 per cent iron and 3 per cent manganese.Previous geological work, mainly by Rudd, Edwards and Miles is reviewed and the results of later exploration by quarrying and drilling are discussed and modified interpretations of both stratigraphy and structure are advanced. Renewed study of the mineralogy of the iron ores is advocated.The Iron Monarch orebody lies on the up-thrown side of a major transcurrent fault that truncates it on its northern boundary. The nearby Iron Knob orebody is believed to occupy a horizon that is some thousand feet stratigraphically above Iron Monarch.The origin of the ore cannot be explained by any simple theory; development probably took place over a long period of time from Lower Palaeozoic to Tertiary.INTRODUCTIONIron Monarch orebody has supplied the Australian iron and steel industry with the greater part of its ironstone requirements since the establishment of the Newcastle steelworks in 1915. Annual production of direct-shipping ore has exceeded three million tons but declined slightly after 1956 when Iron Prince was brought into production. Total production of ore from Iron Monarch to the end of 1962 is about 84,000,000 long tons containing some 55,000,000 tons of metal.The deposit (Lat. 32°44'30"S : Long. 137°08'30"E) is 34 miles north-west of Whyalla, on the western shore of Spencer Gulf. A 42 in. gauge railway connects Iron Monarch and its associated small town of Iron Knob with Whyalla (Fig. 1).For the purpose of this paper Iron Monarch includes Iron Knob and the intervening jaspilite hill known as Substation Ridge, and the description of the general geology necessarily 'Assistant Chief Geologist, The Broken Hill Proprietary Co. Ltd.This paper was presented at the Annual Conference of The Institute, 14-24th August 1968.

Jan 1, 1964

By Douglas H. Brown

Cadmium and other 'minor' metals in Canada tend to remain inconspicuous given the prominence of the country's massive production of other minerals. This same reality is reflected in the accuracy and deficiency of quantitative data concerning the sources of supply and demand for these metals. It is the intent of this paper to identify the nature of some of these difficulties and to reconstruct a more accurate description of Canada's production and consumption of cadmium, based on the results of recent surveys undertaken by the Mineral Policy Sector of Energy, Mines and Resources Canada and Noranda Sales Corporation Ltd.

Jan 1, 1978

By Luis Martín Tejada

Para la evaluación de la estabilidad de taludes en minería superficial se utilizan diferentes métodos de modelamiento y planeamiento como el de simulación numérica. En ese sentido, el presente texto describe el método de tensión-deformación, cuyo base se encuentra en el método numérico de elementos finitos, y así localizar la probable superficie de ruptura. También se describe los mecanismos de ruptura en taludes altos, el cálculo del FS y algunas características del programa de elementos finitos PLAXIS.

Sep 9, 2007

By J. Hartikainen

Kemi cardboard mill is founded on the alluvial bed of Kemi river at the north-eastern cost of Botnic Culf in Northern Finland. The alluvium consists of sandy and silty layers underlain by thick medium dense silty moraine layer. The first cardboard machine, having a belt width of 7,4 m, was constructed in 1972 on 7,5 to 9,5 m long wedge-shaped precast driven piles. Because of the excessive differential settlements and sometimes unexpected dynamic malfunctioning of the machine it was decided to strengthen the foundation before installing the partly new machine and increasing the running speed from 500 to 750 m/min. Piling was done under extremly strick limitations concerning space, vibrations, settlements, dust etc. Extra vertical support was made by using 23...25 long x-form steel piles driven by compressed air pile hammer down to rock. The piles were held together with old piles by a conctrete frame with diagonals, which made the total system - machine - foundation frame, piles and ground - ridgid enough to avoid resonance during dynamic loading.

Jan 1, 2010

By C Li, D O’Dea, R Moreno-Atanasio, T Honeyands

The behaviour of iron ore granules in the feeding process of sintering is significantly influenced by the material properties of the granulated mix. Therefore, the measurement of key material properties of the iron ore granulated mix is indispensable prior to the simulation of the sintering process based on the discrete element method (DEM). In this paper, three key property parameters of the iron ore granulated mix, apparent density, elastic modulus and rolling friction coefficient, were measured in laboratory-scale experiments. For different sintering processes, the moisture content of the granulated mix normally varies according to the specific requirements for granule size distribution and operating conditions. Therefore, understanding the effect of moisture content on the property parameters of iron ore granules is very helpful in accurately determining the property parameters for DEM simulation work. In this paper, six groups of iron ore granule samples with six levels of moisture contents were prepared through granulation and the trends in apparent density, elastic modulus and rolling friction coefficient with the increase of moisture content were plotted and analysed based on the measurement results. The results show that as moisture increases from 6.9 per cent to 9.1 per cent, the apparent density decreases from about 3000 to 2800 kg/m3. With moisture increasing within the same range, the elastic modulus first decreases from over 200 MPa to below 100 MPa and then reaches a relative constant value of about 40 MPa at higher moisture contents. Rolling friction coefficients are measured using two methods with both indicating a similar trend, with the rolling friction coefficient first decreasing and then rising as moisture increases from 6.9 per cent to 9.1 per cent. The relationship between µr and µ’r is assumed to be similar to that between static and dynamic friction coefficients.CITATION:Li, C, Moreno-Atanasio, R, O’Dea, D and Honeyands, T, 2017. Variation in property parameters of iron ore granulated mix with moisture content, in Proceedings Iron Ore 2017, pp 79–84 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017