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By P. Mills

More than 95 percent of all the barite mined and produced is used in the petroleum industry as “drillers mud.” The remaining barite is used in the industrial and medical markets. Therefore, the amount of drilling activity is a good indicator of the health and growth of the barite industry. The four major barite-producing countries in the world are China, the United States, India and Morocco. In 2005, the average number of drilling rigs exploring for oil and gas increased by about 15 percent over the average number in 2004. This increase in oil and gas exploration has resulted in a higher demand for barite and an increase in barite production.

Jan 1, 2006

By G. Halverson, K. Blower

"Giant Yellowknife Mines Limited (Giant) has been producing gold since 1948. Located at Yellowknife, Northwest Territories, Canada, see Figure 1, the mine processes approximately 1,200 short tons per day of 0.23 ounce gold per ton of ore.The majority of the gold in the ore is sub-microscopic and associated within the mineral arsenopyrite. This association complicates the extraction method since straight cyanidation will only recover 30% of the gold. The operations at Giant involve four essential steps, with an overall recovery of 87%. The steps shown in Figure 2 are crushing and grinding, flotation, roasting and cyanidation. These processes result in a number of effluent waste streams characterized in Table 1. These streams are combined and sent to a tailings storage pond for subsequent treatment prior to discharge to the environment.Giant is located just north of the 62nd parallel where winter temperatures drop to -40°C for extended periods. This entails storing effluent in dams over the seven month winter period for treatment during the relatively short summer season.The treatment method currently employed at Giant is an ""alkaline chlorination-arsenic precipitation-flocculation"" process. The pond water is subjected to three phases of treatment prior to being discharged to the environment as shown in Figure 3."

Jan 1, 1987

The 109th Annual General Meeting of The South African Institute of Mining and Metallurgy was held at The Country Club, Johannesburg, Napier Road, Auckland Park on Wednesday, 16 August 2006. Special General Meeting A Special General Meeting to consider the changes to the Constitution was held immediately prior to the AGM. 1. Purpose In order for the SAIMM to remain relevant and ensure maximum value to all members, Council propose three changes to the Constitution. 2. Background Three changes to the Constitution were proposed by the Council on 21 July 2006. These changes now have to be approved by means of a ballot at a Special General Meeting. These three proposed changes are discussed briefly below:

Jan 1, 2006

By L Brodie-Hally

In the early-1990s, Tad Golosinski, the former the head of mining department at WASM participated in a review mining engineering courses in Australia. The review team asked various industry executives what subjects they thought graduates needed to be taught. Tad made the comment to me that the more senior executives thought that history and ethics were very important. The outcome was that the mining engineering courses were required to contain at least five per cent content dealing in ethics. The course was to be modified to reflect this. Tad thought at the time the students would think that subjects dealing in history and ethics came from retirees and professionals that were over the hill. So let me talk to you today about ethics.

Jan 1, 2002

Ecuador a gross domestic product (GDP) grew 8% despite a slowdown in production and sales of petroleum, the dominant economic sector. Crude petroleum exports, which amounted to about 35% of total exports in 1977, were valued et $484 million,2 a decrease of 14% from 1976 values. Petroleum export sales were depressed because foreign buyers were somewhat uncertain that State-owned Corporación Estatal Petrólera Ecuatoriana (CEPE) held legal title to the oil until final settlement with Ecuadorian Gulf Oil Corp. In addition to the legal complication, Ecuador maintained a relatively high export price for oil until late in the year. There was also a shrinkage of traditional U.S, markets owing to the Alaskan pipeline becoming operational and an increased availability of Mexican supplies. The export market was also affected by increased domestic production in Peru and Chile, which lessened their import needs, and the pressure of greater competition from the Middle East in supplying crude oil to Caribbean refineries. About 20.4 million barrels or 40% of Ecuador's total crude exports went to the United States. Only 27 wells were drilled in Ecuador during L977; of these, 16 produced oil, 3 were dry holes, and 8 were suspended. About 31 wells were planned for 1978. Three new oilfields were discovered during 1977; two by CEPE in northeastern Ecuador and one by the Argentine State oil company Yacimientos Petraliferos Fiscales (YPF), operating in Ecuador under a service contract. CEPE's two discoveries tested at 5,000 and 1.450 barrels per day, respectively. The YPF discovery tested at about 1,000 barrels per day. Ecuador altered its position regarding

Jan 1, 1981

Maori economic development still remains an enigma to many people some 157 years after the signing of the Treaty of Waitangi. It has only been in the last decade as a result of increasing pressures from Maori to recognize and settle grievances arising from the Treaty and the resulting compensation issues that "mainstream" has begun to sit up and take notice. While Treaty settlements such as the Tainui, Ngai Tahu and Fisheries settlements have gained prominence as a source of economic potential for Maori, there are significant existing assets owned by Maori worth an estimated $4.6 billion that add an exciting new dimension to Maori contribution to New Zealand's enterprise economy.   Despite the fact that many claims have yet to be resolved, Maori are clearly shifting from grievance to development mode as evidenced by their focus on capacity building through education, strategic alliances nationally and internationally and the significant growth of nett asset worth of Maori interests in a number of industry sectors.   In essence, Maori provide a large un-tapped economic potential in New Zealand. The years of relative economic obscurity appear to have wetted their appetite for positive growth and economic independence. Given current trends, it would not be unrealistic to expect the asset base of Maori to double in value over the next decade and to see the emergence of Maori owned Corporates not only within the New Zealand economy but also trading actively in the global market place.

Jan 1, 1997

By F. Calizaya

This paper describes the basic requirements for the utilization of belt air to ventilate working sections at remote locations in relation to the main fans. It highlights the risks involved, potential problems, and the provisions that must be followed by mine operators for the safe use of belt air. The paper also presents a brief review of the current regulations, conveyor belting tests, atmospheric monitoring system requirements, and the experience gained by mine operators to utilize the belt entries to ventilate remote working sections or areas where mechanized equipment is being installed or removed. The paper concludes with a set of recommendations with respect to the utilization of belt air and the composition of belt material in under-ground coal mines.

Jan 1, 2008

By Michelle Cardinale Souza Silva Macedo

Neste trabalho, o comportamento eletroquímico das ligas Ti-35Nb-xTa (x = 0; 2,5; 5,0; 7,5)Ta (% em peso), solubilizadas e resfriadas em água, foi investigado em meio de NaCl a 0,9% mol/L através de testes de polarização anódica e medidas de impedância, micrografias e DRX. Os ensaios eletroquímicos mostraram que as ligas contendo tântalo apresentam uma maior resistência à corrosão que a liga sem tântalo. Além disso, os ensaios eletroquímicos em conjunto com as micrografias e DRX indicam que a composição Ti-35Nb-5Ta é a que apresenta maior resistência à corrosão no meio estudado, pois além de ocorrer uma estabilização da fase ?, o refino do grão foi menos pronunciado e por esse motivo minimizou o surgimento de microcélulas eletroquímicas.

Aug 16, 2017

By D. J. Zhao

The reduction of ilmenite pellets was investigated at 950°C and 1000°C under a CO-N2 gas mixture with 10 L/min gas flow rate. All the reducing reactions were conducted in a furnace with a thermogravimetric analysis system. The reduction rate is higher at 1000°C than that at 950°C. At the early stage of the reactions, with the CO concentration increasing in the gas mixture, the reduction rate increased at 1000°C. In addition, at the early stage of the reactions, a rapid temperature increment and a rapid conversion of oxygen were observed on the curves of temperature versus time and conversion of oxygen versus time under different experimental conditions. The solid reaction products obtained in these experiments were analyzed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometers (EDS). Metallic Fe with small amount of Ti dissolved in it and oxides of Ti were found in the solid reaction products, but the formation of any nitride phases was not found under the prevailing conditions.

Jan 1, 2014

By P. M. Pettit

Hydrologic investigations at Gold Quarry began in 1989 and continued through 1991. Hydro-stratigraphic units include Tertiary sedimentary rocks, Paleozoic siltstones and carbonates. These units display complex and variable aquifer parameters as a function of faulting and hydrothermal alteration, creating compartmentalized hydrologic domains. Testing has included step-tests, spinner production logs and constant discharge tests. Two Three-Dimensional Finite Element Models have been developed, one for optimizing the pit dewatering system and the second for predicting regional impacts of dewatering. Aquifer testing and long term pumping have been used to calibrate both Finite Element Models.

Jan 1, 1992

By J. C. Edwards

A series of four coal combustion experiments (I)' was conducted at the National Institute for Occupational Safety and Health, Pittsburgh Research Laboratory in the Safety Research Coal Mine to evaluate the response of optical and ionization smoke and CO sensors to a small 0.61 m square smoldering coal fire which transitions to flaming combustion in the presence of diesel emissions. With the increased utilization of diesel engines in underground coal mines, it is important to be able to discriminate fire products-of-combustion (POC) from diesel emissions. One proposed method to accomplish this is the deployment and interpretation of multiple sensors.

Jan 1, 2010

By T. R. Curr, R. T. Jones

Keywords: Pyrometallurgy, Mintek, DC arc furnace, plasma, smelting, chromite, ilmenite, cobalt, slag, zinc fuming, dust, magnesium, laterite, ferronickel, arc modelling, Pyrosim, thermodynamics The Pyrometallurgy discipline at Mintek was initiated in the early 1970s, to support a growing ferroalloy industry in South Africa. In addition to a range of pyrometallurgical options, Mintek specialises in DC arc furnace technology and has pilot plant facilities up to 5.6 MVA, as well as a strong base in process and arc modelling. Industrial processes have been developed for ferrochromium production, ilmenite smelting, and cobalt recovery from slag. Recent work has been done on such processes as the production of ferronickel from laterite ores, the fuming and condensation of magnesium, and the recovery of platinum group metals from 'difficult' feedstocks.

Jan 1, 2006

By Michael Mann

Two house trailers and a modem modular house, all pillar-supported with cantilevered perimeters, were monitored for structural response to vibrations from surface coal mine blasts. Due to the large blast site distances, peak particle velocities measured in the ground beside the houses did not exceed 0.32 ips, and airblasts did not exceed 106 dB. However, the structures responded significantly to the ground vibrations, with maximum high-comer amplification factors as high as 8.5 in the horizontal directions. Vertical structural responses were as high as 10 times the vertical peak particle velocities in the ground, but appeared to be driven more by horizontal ground motions. No measurable airblast responses were observed. The natural frequencies of the structures ranged from 5 to 10 Hz.

Jan 1, 2000

By D. J. Greeff

By making use of genetic programming, empirical models for metallurgical processes can be evolved that are more cost-effective than models determined by means of classical statistical techniques. These methods explore populations of candidate models assembled from sets of variables, parameters and simple mathematical operators, and do not require explicit specification of model structures. The application of the proposed strategies is illustrated by means of a case study pertaining to the leaching of nickeliferous chromite ores. Modelling of the nickel and cobalt extraction from the ores yielded models of similar accuracy compared to those obtained by non-linear regression and artificial neural networks. However, in the case of the iron extraction from the ores, the genetic programming model was significantly more accurate than both the regression and neutral network models.

Jan 1, 1998

By Weiran Zuo, Wanzhong Yin, Jin Yao, Keqiang Chen, Qiuyue Sheng, Liu Liu

It is important to investigate the liberation properties of gangue minerals and establish liberation models for low-grade iron ores to reject gangue early. In this study, three types of iron ores from different iron deposits were ground to different particle size distributions by locked-cycle grinding and batch grinding. The liberation distribution of quartz, the most dominant gangue mineral among the three types of iron ores, was tested by Mineral Liberation Analyzer (MLA). Afterward, the liberation distribution of the three types of quartz was fitted using the beta distribution function, and their shape parameters were related to particle sizes to develop the liberation model. MLA test results showed that the liberation distribution of quartz with different grinding methods was basically the same. The developed liberation model predicted the liberation distribution of quartz in low-grade iron ores from different iron deposits well, and its coefficient of determination (R2) was between 0.90 and 0.98. This study deepens the understanding of the liberation rules of quartz in low-grade iron ores from different iron deposits, and on this basis, a more efficient liberation model based on the beta distribution function is developed.

Oct 18, 2023

By D. O. Tansey

This paper will describe the mechanisms involved in delay blasting and how they are applied with the use of D.S.B. It will examine the control of potential damage resulting from detonations, and show how good fragmentation and efficient recovery of this material blasted can be achieved.

Jan 1, 1979

Much attention in controlling blast vibrations has been centred on the probability of causing damage to structures in the area adjacent to where blasting is carried out. In most cases these structures are residential properties and the effect of the vibrations on the occupiers has not been studied to any great extent. This paper looks at the sources of disturbance caused by blasting and their psychological effect. A comparison of ground vibration levels for compliance is examined within the framework of structural and human response.

Jan 1, 1998

By J. I. Mathis

"The failure that was utilized for developing this model was a double bench-scale failure, approximately 20 m in height, in the Misery pit at BHP Billiton’s EKATI mine site. The bench that failed was excavated in biotite schist. Due to previous problems with bench-scale toppling failures, this bench was excavated with a 70° inclined, 30 m deep preshear. Upon exposure, the wall was very clean with half-barrels commonly observed from the pre-shear operation.In August 2003, a bench failure of about 1000 t occurred in this pre-sheared biotite schist (Fig. 1). Upon examination it was noted that the foliation that paralleled and dipped at 70° into the face when excavated was approximately horizontal at the top of the failure (Fig. 2). While the failure mode itself appears complex, the failure was apparently driven by three factors:• a low-angle, low-frictional strength fault or discontinuity at the base of the failure area;• water either contributed meteorically from precipitation and/or from permafrost melt; and• foliation planes providing a viable toppling geometry once toe block motion began to occur.The above details are illustrated in Figure 3.After considerable thought and analysis, a model was postulated for the failure.It is thought that the entire failure had been triggered by displacement of a toe block (Fig. 4). This toe block is bounded on the back by foliation, the bottom by a low-angle, lowstrength fault, and the front by the bench face. Water pressures behind the bench face developed forces on the block as can be seen in Figure 5. These forces were sufficient to induce block motion. As can be seen in the relative shear strength diagram in Figure 6, only a small amount of water is necessary in the face to initiate block displacement. Note that in this figure, a simplistic piezometric pressure distribution was assumed."

Jan 1, 2004

Engineering education has become a matter of national concern, at last, so I would like to talk about the links between the mining industry, the universities and technological developments. The Australasian mining industry and the mining schools have collaborated closely since the first school was established in 1871 and during those years there were a series of remarkable technological developments. For example:In the late 1880s George AndersoIl Richard developed chloride leaching of gold at Mt Morgan. This made a large difference to the wealth of Mt Morgan Mining Ltd.In the mid 1890s Robert Sticht demonstrated that pyrite smelting was an economically feasible process at Mt Lyell and the wealth which came to Mt Lyell Mining Co from his outstanding work made it one of the great companies in the country.During the first 15 years of this century flotation was developed at Broken Hill and it has proved to be one of the great technological inventions of this century.In the 1920s G K Williams started his outstanding work on lead smelting and refining at Port Pirie, this was work which ultimately re-wrote the text book on lead metallurgy and established Port Pirie as the mecca for lead metallurgists.In the 1920s also Frank Stillwell, later joined by Austin Edwards, established the new science of mineragraphy at the University of Melbourne. They were both great geologists, both were superb scientists and oddly enough both were outstanding athletes.In the 1930s Dr Ian Wark, a man in the front rank of Australian scientists of any period, started his outstanding work on flotation, work which resulted in a text book which remains a leader in its field today.In the 1930s also Arnold Black at Broken Hill South Ltd picked up the work which had been done at Mt Lyell many years previously and eventually wrote the papers on hydraulic fill which demonstrated that he led the world in fill technology. What a remarkable story of achievement it was, it laid the groundwork for the great industry we have today. It was possible because the industry was well supported by outstanding university schools and I would like to talk about some of these.

Jan 1, 1989

By R. Saulters, M. Garshasb

The Transportable Moisture Limit (TML) is the copper concentrate moisture content beyond which liquefaction may occur during shipping. This study indicates that TML is a function of mineralogical characteristics of concentrate, which in turn may directly affect moisture retention properties. A comprehensive mineralogical and chemical analysis was conducted to determine the impact of composition and mineral content on concentrate’s TML. The analysis indicates that the high TML value is associated with particular minerals such as gypsum, swelling clay, muscovite and pyrite. Since higher TML values allow higher moisture contents for shipping, this property is desirable for concentrate inventory management and shipping flexibility. Scarcity of minerals that may increase TML contributes to limitations of shippable inventory. INTRODUCTION TML is the maximum moisture content of copper concentrate beyond which liquefaction may occur. Moisture content above the TML is considered a shipping hazard as it may result in loss of lives and cargo. The details of TML testing are given in ISO 12742:2007 (ISO 12742). In principle, TML is 90% of the Flow Moisture Point. The method of testing for Flow Moisture Point and TML is based on procedures that provide pulsations that simulate the cyclic force of ocean waves to determine moisture levels at which the onset of concentrate flow may occur. International Maritime Organization (IMO) provides guidelines for developing and approving TML testing and moisture determination in the context of its Moisture Management Plan (MMP) for shipment of copper concentrate cargoes (IMO 2013). The IMO regulations are specifically provided in MSC.1/Circ. 1454 “Guidelines for developing and approving procedures for sampling, testing and controlling the moisture content for solid bulk cargoes which may liquefy”. Since each port has its own operational characteristics, resource availability, peculiarities of governmental structure, and desired methods of interaction with the authorities, it is necessary to adopt the IMO guidelines to the local requirements. In order to establish a TML and MMP measurement system, it is required to implement and follow proper guidelines for the relevant procedures. For example, sampling procedures are developed in accordance of ISO 12743, “Copper, lead, zinc, and nickel concentrates – Sampling procedures for determination of metal and moisture content”. Moisture content of copper concentrate samples are determined in accordance with ISO 10251, “Copper, lead, zinc, and nickel concentrates – Determination of mass loss of bulk material on drying”. To assure strict adherence to the MMP procedures, the overall system needs to be integrated into the site QA/QC system, which would make them auditable and certified in accordance with standards such as ISO 9001, ISO 17025, and ISO 17020.

Jan 1, 2019