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By S Brown

With oxygen conditioning routinely used in both the lead and zinc circuits at Pasminco Elura Mine a more sophisticated method of determining oxygen demand was required. It is known that different ore types have different oxygen consumption rates, however oxygen is added at a fixed rate regardless of ore type in the plant. Therefore, a simple laboratory test was devised to measure the oxygen demand of ores. The paper describes the technique employed, and provides an interpretation of the results. These data, together with pulp chemical measurements (Eh, pH and EDTA extraction data) were correlated against laboratory flotation performance to establish the relationship between oxygen demand and the position of the grade/recovery curve.

Jan 1, 2000

By Q Fan

The steelmaking desulfurisation plays an important role in coal-based steelmaking route of blast furnace and BOF converter within the flow sheet of BF-deS-BOF. With the advent of H2-based ironmaking and steelmaking process, the transition flow sheet of DRI-Smelter-BOF has been assessed and developed by the steelmaking industry. What is the role of deS in H2-based route of DRI-smelter-BOF? This paper will present the influence of sulfur-containing iron ore on steelmaking desulfurisation and the leading role of EAF-smelter played in H2-based steelmaking route. The sulfur contents of iron ore vary considerably around the world and lower-grade iron ores with high sulfur are likely to be used for H2-based route, a considerable amount of sulfur that comes from DRI will report to the melt of EAF-smelter and the operating conditions of EAF-smelter also impact the sulfur content of the hot melt for steelmaking deS. The EAF-smelter of H2-based route is the focus of the steelmaking industry at moment, unfortunately, an industrial-scale EAF-smelter has been the missing link of the flow sheet of DRI-Smelter-deS-BOF, despite similar EAF-smelters being used for various applications of Fe-Ti and Fe-Ni processes. The latest progress is that several pilot-scale and industrial-scale EAF-smelters with reducing capability are planned for construction within next several years and low-grade Australia iron ores are certainly to be employed as basic feedstocks for H2-based route of DRI-Smelter-deS-BOF.

Sep 18, 2023

By K S. Park, J K. Kim, J H. Park, Y Su

The present study investigates the possibility of the direct removal of oxygen from the Ti-30Ni (wt per cent) alloy melt through the thermodynamic equilibrium reactions at 1623 K in the vertical tube furnace. The deoxidation efficiency of Ti-Ni alloy melt by adding different contents of metallic calcium (Ca) as a deoxidant was evaluated with the binary CaF2-MgCl2 flux. The thermodynamic equilibrium experiments showed that the total oxygen content in the alloy decreased from about 650 ppm to 350 ppm when 3.5 wt per cent Ca was added to the Ti-30Ni (wt per cent) alloy. Alternatively, the effect of flux composition in the CaF2-MgCl2 flux on the oxygen content was also investigated at 1623 K. Therefore, the effect of binary flux systems on the deoxidation ability was compared at 1623 K. According to the results, the flux system with 80 per centCaF2– 20 per centMgCl2 exhibited the best deoxidation capability, ie total oxygen content in the alloy reduced from 1450 to 550 ppm.

Aug 21, 2024

In the geologically prospective nations which rim the Pacific Ocean, mineral deposits offer great potential to create wealth for social and economic development. The paper first examines the geological and economic attributes of potential mineral wealth based on current outlook assessment of all significant base metal deposits discovered to 1988 in two Pacific Rim nations - Australia and Canada. The variability of mineral wealth among the economic deposits evaluated and the major contribution of the few world-class discoveries to total mineral wealth are highlighted. Then, the essential but too often neglected linkage between the makeup of potential wealth and its actual realization is analyzed. The impact of taxation and the role of exploration are crucial in this regard. Finally, the ingredients of exploration success, prerequisites for realizing the mineral wealth of nations, are examined.

Jan 1, 1995

By Juras ST, Krouse RH, Godwin CI

The Buttle Lake camp is in central Vancouver Island, southwestern British Columbia, Canada. The camp hosts world-class polymetallic volcanogenic deposits of Devonian, Frasnian age (370Ma). This paper describes an on-going sulphur and lead isotope study of the major orebodies.Sulphur isotopes were determined for sulphides (pyrite, chalcopyrite, bornite and galena) and sulphate (barite). Sulphide analyses are markedly different from sulfate. The differences are explained below in a unique model.Sulphide isotopic compositions cluster tightly (del34S -6.7 to 4.6), and demonstrate isotope reversals. Calculated temperatures of correctly ordered mineral pairs are unrealistically high. We conclude that the sulphides are in isotopic disequilibrium, presumably because of rapid precipitation from a quenched plume in an anoxic environment, and because of subsequent sulphide replacement.

Jan 1, 1990

By B Laidens, D Souza, W Bielefeldt

The CaO-MgO-SiO2-Al2O3 system, characterised by its intricate phases and thermodynamic properties, plays a pivotal role in steel secondary refining processes, encompassing desulfurisation, non-metallic inclusion capture, and refractory protection. Accurate predictions for diverse industrial applications, including metallurgy, ceramics, and materials science, are imperative. To address this challenge, a combination of machine learning techniques will be specifically applied to model the liquid fraction of the slag and the solid fraction of MgO. The development of an artificial intelligence (AI) system, leveraging various machine learning techniques, has gained momentum in this project. The focus of this work is on constructing an AI model, based on machine learning techniques, within the CaO-MgO-SiO2-Al2O3 system, utilising simulation results from FactSage™, version 8.1 (by GTT Technologies). The primary objective is to train the AI model using these simulation outputs to predict the percentage of liquid fraction and MgO saturation based on chemical composition parameters. The AI model will undergo training with a comprehensive data set of simulations within the CaOMgO- SiO2-Al2O3 system, covering a diverse range of compositional at 1873 K. These simulations, conducted through FactSage™ 8.1 software, provide a robust foundation for AI model training, ensuring generalisability and precise predictions for the liquid fraction of the slag and the solid fraction of MgO, the solid fraction of MgO in this case is determined by the difference between the total MgO and the MgO in the liquid fraction, so it is not the objective of this study to determine which phase of MgO is in the solid state.. The predictive capabilities of this AI model hold significant implications for process optimisation, quality control, and decision-making in CaO-MgO-SiO2-Al2O3- dependent industries. Precise estimations of the liquid fraction and MgO saturation empower researchers and engineers to enhance operational efficiency and quality. This paper explores the methodologies employed for AI model creation and training, achieved results in terms of prediction accuracy, and potential applications in the field. The development of this AI system signifies a notable advancement in utilising machine learning for better comprehension and control of complex chemical systems. Furthermore, to align the study with real-world steel production, we introduce FeO and MnO at concentrations of 2 per cent and 1 per cent at 1873 K, respectively, following the validation of model results using the CaO-MgO-SiO2-Al2O3 system. This adjustment aims to bring the study closer to the observed reality in steel mills globally.

Jun 19, 2024

By A Van Kersen, J Hodson

Waihi Gold Mining Co Ltd [WGM], operated by Normandy Mining, has been internationally recognised for its achievements in environmental management at the Martha Mine at Waihi. In a proactive approach to dealing with community concerns regarding blast vibrations on the North Wall cutback, trials were performed using the Cardox System [Cardox], to determine feasibility of achieving economic fragmentation of andesite overburden whilst bettering management levels of 5 mm/s peak particle velocity. Cardox is a non-explosive pressure breaking system which uses high pressure CO2, Results against conventional Ammonium Nitrate/Fuel Oil [ANFO] using a variety of delays showed that conventional blasting techniques could produce marginal fragmentation within the management levels with occasional excursions, whereas Cardox produced the required fragmentation while not registering on the vibration monitoring equipment. Fragmentation to enable normal excavation by a Hitachi EXII00 hydraulic excavator was achieved with a yield of 16m3 per round. The trails indicated that fragmentation with Cardox at the yields required of over 18m3 per round was possible with further product development. The trial demonstrated that non-explosive pressure breaking is feasible and its application warranted where environmental concerns affect the cost-benefit economics of production blasting in sensitive areas.

Jan 1, 2001

Initial coal production at Ulan was solely from underground mines. A significant increase in demand for steaming coal in the late 1970's emphasised the need to further expand production and led to the development of the open cut mine which commenced commercial production in June, 1982.During the initial stages of mine planning, feasibility and cost studies were undertaken to determine the most suitable method for coal haulage from the pit. The comparison between a conventional truck haulage system and an in-pit crushing system using a mobile crusher and moveable belt conveyor haulage confirmed that the mobile crusher and conveyor system was superior in every respect for the Ulan mining operations.Technical features and design parameters for the major items of equipment are outlined as well as operating, manning and performance assessments. Minor equipment problems were encountered during initial operation but these have since beenrectified and the plant is now capable of exceeding the design production. Maintenance and energy costs are considerably lower than originally estimated and production efficiencies are continually improving as operators develop new techniques and procedures in the handling of the equipment.

Jan 1, 1985

By Klinefelter G

The United States Steel Mining Co., Inc. recently experienced a major mine fire at the Cumberland Mine. This mine is located in Greene County, Pennsylvania, U.S.A. and is mining a high volatile bituminous coal seam (Pittsburgh Seam). The mine fire was success- fully controlled and extinguished without loss of life or serious injury to any miner or mine rescue personnel and finally reopened within 40 days of its inception.

Jan 1, 1988

By Johns AS

Comissioning of a new residue disposal tcluding upgraded classification for none backfill preparation, new variable speed pumps and a new residue dam took place in 1¦76. The system is described.

Jan 1, 1978

By ZáWang, F Hungerford, T Ren

Operations in an underground drill site have to co-exist within the mineÆs ventilation and operational system. The space requirements of a drilling operation have to be adapted to the limitations provided in available site space, which is usually defined by standard mining operations and geotechnical influences. These limitations affect borehole design, equipment positioning in the site layout and possible interactions with mining equipment and services such as water and power supply.The ventilation requirements for drill sites and the means employed vary with depth of the site, space and likely presence of gas. All drilling operations provide a particular service for the mine and in each case, drilling must operate in a manner which controls all gas, water and cuttings returning from the borehole. The various standpiping systems employed have evolved under differing influences and must cater for conditions during and after the drilling operations.The influences that gas content, pressure and flow, rib stability, cleat direction, borehole length, potential water pressure and flow have on a mineÆs operation and ventilation systems have to be considered in the design of standpipe length, diameter and fittings. Past history has a strong influence on common practice while worst case effects of a possible in-hole event should be catered for.This paper describes the early drilling systems and their limitations in ventilation and gas management. The drill site dimensions and set-up are discussed in the context of roadway conditions, equipment layout, ventilation and logistics. The use of standpiping to control all returns from the borehole is illustrated by referring to likely scenarios in a drilling site to achieve the most effective sealed depth to accommodate the worst case possibility of intersecting high pressure gas or water during the drilling operation. Practices to allow gas drainage in the return airway of a panel are described.CITATION:Hungerford, F, Ren, T and Wang, Z, 2013. operational management of underground in-seam drilling sites, in Proceedings The Australian Mine Ventilation Conference , pp 43-48 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By Cullen JF

Australia has a large resource of manganese at BHP's Groote Eylandt mine which has been progressively developed over the last two decades. While much of the product is marketed internationally to the iron and steel industry, substantial quantities are processed in Australia at the Company's ferro alloy works in Tasmania. In addition, small but increasing quantities of ore are being consumed by the non-metallurgical industry. Fluctuating fortunes in the steel industry produce similar trends in the marketing of manganese. The increasing cost of freight and power together with strict environmental control is further affecting the market balance. Mine operators are expanding into the alloy making field. Reduction in usage in less developed countries is occurring.

Jan 1, 1982

By Kurzeme M, Willoughby D. R

Current research at the CSIRO, Division of Applied Geomechanics, into the mode of response of fill as a structural component has been based on model tests for prediction of behaviour and field observation of critical parameters. The procedure is summarised in four stages: (a) define the specific fill function (b) postulate the mode of failure (c) use models to quantify the conditions (d) monitor critical parameters to check or update the analysis in (c). The above procedure is used to postulate the failure modes of each of the possible func- tions performed by fill materials. Analytical techniques, or lines of investigation, are described for each of these modes and specific reference is made, where, possible, to an exis- ting mine environment.

Jan 1, 1973

The rocks of the Serranias Chilla massif of Bolivia are a suite of metamorphosed Palaeozoic basalts and associated continental sediments. Whole-rock trace element geochemistry of the basalts suggest a calc-alkaline affinity and indicate that subduction extended as far north as the Bolivian Altiplano during lower Palaeozoic time.

Jan 1, 1990

By Xueqiu H

Since the hypothesis of coal and methane outburst mechanisms based on elastic mechanics gives no consideration to time, it cannot give satisfactory explanation of the outburst occurrence and its development. A creep mathematical model of coal containing gas has been set up through creep tests and analysis under a condition of triaxial compression. Such a model can explain the phenomenon of coal and methane outbursts successfully. The tests proved that there is no essential difference between the rheological properties of prone outburst coal and non-prone outburst coal. Outburst can take place in any kind of coal if the rheological conditions of coal containing gas are met. The creep mathematical model provides a basis for establishing a comprehensive index of coal and methane outburst potential.

Jan 1, 1992

By Mahoney BK

The development of simulation models to reflect accurately the operations of a port and its associated transportation systems can be an expensive and time consuming process. However the complexity of such operations leaves little choice for other than simulation techniques since analytical methods are rarely appropriate. The development of suitable software has now reached the stage that these techniques can be used with confidence. Types of simulation models and their requirements are discussed together with the results from some recent applications to the planning and management of bulk terminals.

Jan 1, 1983

By LefTvre Y

In May 1991, AZSA commissioned a new conventional Cell House. This paper focuses on the major improvements introduced in the design and the construction of the equipment, machinery and control. An effective control system together with good reporting and routine operation has resulted in quality control of the Cell House at the highest possible level. Consequently the monthly current efficiency consistently averages above 93 per cent with a total energy usage of 3000 AC kWh/t of cathode zinc. The new concept for the year 2000 and beyond is introduced.

Jan 1, 1993

The technology of coal preparation, while based on similar processes to those in common useage in the 1950s, has improved significantly over the past 15 years primarily due to advances in process control. This technology at least offers the potential for most coal preparation unit operations to be optimised to a considerable degree. However, to maximise the overall yield of an operation from pit to port, factors often outside of the control of the preparation plant operator have a dominant effect. Specific factors include an in depth knowledge of the feed characteristics of the various sources of coal, the detailed mine scheduling to provide an appropriate blend to the plant, and the interim handling and stockpiling processes between the mine face and the customer.This paper summarises the criteria for optimising the yield for a variety of mining, processing and stockpiling options, based on the principle of operating at constant incremental ash. Pragmatic operating assumptions such as extension of the principle to operating at a constant density for gravity operations will be discussed. A means of optimising the compromise between maintaining specification product ash to the customer and maximising yield by always washing at constant incremental ash, without the benefit of a homogenised feed, will also be Presented.

Jan 1, 1992

Renison Limited produces high and low grade tin concentrates at an annual rate of 5000 tonnes of contained tin metal. In spite of the fine average cassiterite grain size, emphasis is placed on gravity concentration methods to produce a high grade final product. Cassiterite flotation is considered and operated as a gravity circuit scavenger responsible for approximately 15 percent of recovered tin metal as a fine grained low grade concentrate. Metallurgical problems mainly result from ore-type variations which may be aggravated by a number of circulating loads. The rationalisation of circuitry is being studied to provide more effective control by operators and to allow exploitation of current control and modelling techniques.

Jan 1, 1977

ABSTRACT' The first references to gold in New Guinea were by the Portuguese in 1525. The first significant discovery and gold rush was on Sudest Island in 1888 and was a natural extension of the rush that surged up Australia's eastern coast and ended at cook- town. Prospectors made a series of minor discoveries in coastal regions before the first large discovery at Wau/Edie Creek/Bulolo in 1925. Major post war gold discoveries were made at Bougainville, Frieda River, Porgera and Ok Tedi. On Misima Island a large bulk low grade deposit has been recognised surrounding old gold workings. Gold exploration has increased drama- tically since the lifting of a 3 year moritorium on new exploration areas in Noverrber 1982. A new bulk low grade gold discovery has been made on Lihir Island, north of Bougainville and a number of other promising areas are being drilled. Gold production is also expanding dramatically from current levels of 600,000 ounces to an anticipated 1.3 million ounces in 1985 with the opening of Ok Tedi. Other potential developments are likely to increase output above 2 million ounces by 1990. Papua New Guinea's world ranking as a producer is likely to move from 9th to 7th in 1985 reflecting the favourable geological potential, stable political environment and attractive development terms offered by the Government.

Jan 1, 1984